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Sample records for improved sfr cores

  1. An improved energy-collapsing method for core-reflector modelization in SFR core calculations using the PARIS platform

    Energy Technology Data Exchange (ETDEWEB)

    Vidal, J. F.; Archier, P.; Calloo, A.; Jacquet, P.; Tommasi, J. [CEA, DEN, DER, Cadarache, F-13108 Saint-Paul-lez-Durance (France); Le Tellier, R. [CEA, DEN, DTN, Cadarache, F-13108 Saint-Paul-lez-Durance (France)

    2012-07-01

    In the framework of the ASTRID project, sodium cooled fast reactor studies are conducted at CEA in compliance with GEN IV reactors criteria, particularly for safety requirements. An improved safety requires better calculation tools to obtain accurate reactivity effects (especially sodium void effect) and power map distributions. The current calculation route lies on the JEFF3.1.1 library and the classical two-step approach performed with the ECCO module of the ERANOS code system at the assembly level and the Sn SNATCH solver - implemented within the PARIS platform - at the core level. 33-group cross sections used by SNATCH are collapsed from 1968-group self-shielded cross-section with a specific flux-current weighting. Recent studies have shown that this collapsing is non-conservative when dealing with core-reflector interface and can lead to reactivity discrepancies larger than 500 pcm in the case of a steel reflector. Such a discrepancy is due to the flux anisotropy at the interface, which is not taken into account when cross sections are obtained from separate fuel and reflector assembly calculations. A new approach is proposed in this paper. It consists in separating the self-shielding and the flux calculations. The first one is still performed with ECCO on separate patterns. The second one is done with SNATCH on a 1D traverse, representative of the core-reflector interface. An improved collapsing method using angular flux moments is then carried out to collapse the cross sections onto the 33-group structure. In the case of a simplified ZONA2B 2D homogeneous benchmark, results in terms of k{sub eff} and power map are strongly improved for a small increase of the computing time. (authors)

  2. Fine Distributed Moderating Material with Improved Thermal Stability Applied to Enhance the Feedback Effects in SFR Cores

    Directory of Open Access Journals (Sweden)

    Bruno Merk

    2013-01-01

    Full Text Available The use of fine distributed moderating material to enhance the feedback effects and to reduce the sodium void effect in sodium-cooled fast reactor cores is described. The influence of the moderating material on the fuel assembly geometry, the neutron spectrum, the feedback effects, the power and burnup distribution, and the transmutation performance is given. An overview on possible materials is provided and the relationship between hydrogen content and thermal stability is described. A solution for the problem of the limited thermal stability of primarily proposed hydrogen-bearing moderating material ZrH1.6 is developed by the use of yttrium-mono-hydride. The similarity in the effects reached by ZrH and YH is demonstrated by comparison calculations. The topic is closed by an overview on material properties, manufacturing issues, experience in fast reactors, and a comparison of raw material costs.

  3. Evaluation of AGNI SFR core neutronics parameters with VESTA and ERANOS

    Science.gov (United States)

    Ecrabet, Fabrice; Haeck, Wim; Chaitanya Tadepalli, Sai

    2014-06-01

    This paper presents the calculation of core neutronics parameters for so called AGNI Sodium Fast Reactor (SFR) model performed with ERANOS code and Monte Carlo depletion interface software VESTA. The AGNI core has been developed at IRSN for its own R&D needs, i.e. to test performance of calculation codes for safety assessment of a generation IV SFR project. The ERANOS code is used as reference code for SFR core calculations at IRSN. In this work, VESTA calculations have been performed and compared with corresponding ERANOS results. These calculations have a double purpose: mastering the use of tools for the evaluation of SFR core static neutronics parameters and validate the use of VESTA for SFR cores.

  4. An Improved Dynamic Joint Resource Allocation Algorithm Based on SFR

    Directory of Open Access Journals (Sweden)

    Yibing Li

    2016-04-01

    Full Text Available Inter-cell interference (ICI is the main factor affecting system capacity and spectral efficiency. Effective spectrum resource management is an important and challenging issue for the design of wireless communication systems. The soft frequency reuse (SFR is regarded as an interesting approach to significantly eliminate ICI. However, the allocation of resource is fixed prior to system deployment in static SFR. To overcome this drawback, this paper adopts a distributed method and proposes an improved dynamic joint resource allocation algorithm (DJRA. The improved scheme adaptively adjusts resource allocation based on the real-time user distribution. DJRA first detects the edge-user distribution vector to determine the optimal scheme, which guarantees that all the users have available resources and the number of iterations is reduced. Then, the DJRA maximizes the throughput for each cell via optimizing resource and power allocation. Due to further eliminate interference, the sector partition method is used in the center region and in view of fairness among users, the novel approach adds the proportional fair algorithm at the end of DJRA. Simulation results show that the proposed algorithm outperforms previous approaches for improving the system capacity and cell edge user performance.

  5. Improving SFR Economics through Innovations from Thermal Design and Analysis Aspects

    Energy Technology Data Exchange (ETDEWEB)

    Haihua Zhao; Hongbin Zhang; Vincent Mousseau; Per F. Peterson

    2008-06-01

    Achieving economic competitiveness as compared to LWRs and other Generation IV (Gen-IV) reactors is one of the major requirements for large-scale investment in commercial sodium cooled fast reactor (SFR) power plants. Advances in R&D for advanced SFR fuel and structural materials provide key long-term opportunities to improve SFR economics. In addition, other new opportunities are emerging to further improve SFR economics. This paper provides an overview on potential ideas from the perspective of thermal hydraulics to improve SFR economics. These include a new hybrid loop-pool reactor design to further optimize economics, safety, and reliability of SFRs with more flexibility, a multiple reheat and intercooling helium Brayton cycle to improve plant thermal efficiency and reduce safety related overnight and operation costs, and modern multi-physics thermal analysis methods to reduce analysis uncertainties and associated requirements for over-conservatism in reactor design. This paper reviews advances in all three of these areas and their potential beneficial impacts on SFR economics.

  6. Impact of the control rod consumption on the reactivity control of a SFR break-even core

    Energy Technology Data Exchange (ETDEWEB)

    Blanchet, D.; Fontaine, B. [CEA, DEN, SPRC, Cadarache, F-13108 Cedex Saint-Paul-lez-Durance (France)

    2012-07-01

    Current design studies on Sodium Fast Reactor (SFR) differ from those performed in the past by the fact that design criteria are now those of the Generation IV reactors. In order to improve their safety, reactors with break-even cores are preferred because they minimize the needs in terms of reactivity control and limit the consequences of control rod withdrawal. Furthermore, as the reactivity control needs are low, break-even core enables the use of absorbing materials with reduced efficiency (natural boron, hafnium...). Nevertheless, the use of control rods with few absorbing materials may present the disadvantage of a non-negligible ({approx}10%) loss of efficiency due to their consumption under irradiation. This paper presents a methodology to calculate accurately and analyze this consumption. (authors)

  7. Assessment of SFR reactor safety issues: Part II: Analysis results of ULOF transients imposed on a variety of different innovative core designs with SAS-SFR

    Energy Technology Data Exchange (ETDEWEB)

    Kruessmann, R., E-mail: regina.kruessmann@kit.edu [Karlsruhe Institute of Technology, Institute of Neutron Physics and Reactor Technology INR, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Ponomarev, A.; Pfrang, W.; Struwe, D. [Karlsruhe Institute of Technology, Institute of Neutron Physics and Reactor Technology INR, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Champigny, J.; Carluec, B. [AREVA, 10, rue J. Récamier, 69456 Lyon Cedex 06 (France); Schmitt, D.; Verwaerde, D. [EDF R& D, 1 avenue du général de Gaulle, 92140 Clamart (France)

    2015-04-15

    Highlights: • Comparison of different core designs for a sodium-cooled fast reactor. • Safety assessment with the code system SAS-SFR. • Unprotected Loss of Flow (ULOF) scenario. • Sodium boiling and core melting cannot be avoided. • A net negative Na void effect provides more grace time prior to local SA destruction. - Abstract: In the framework of cooperation agreements between KIT-INR and AREVA SAS NP as well as between KIT-INR and EDF R&D in the years 2008–2013, the evaluation of severe transient behavior in sodium-cooled fast reactors (SFRs) was investigated. In Part I of this contribution, the efficiency of newly conceived prevention and mitigation measures was investigated for unprotected loss-of-flow (ULOF), unprotected loss-of-heat-sink (ULOHS) and the unprotected transient-overpower (UTOP) transients. In this second part, consequence analyses were performed for the initiation phase of different unprotected loss-of-flow (ULOF) scenarios imposed on a variety of different core design options of SFRs. The code system SAS-SFR was used for this purpose. Results of analyses for cases postulating unavailability of prevention measures as shut-down systems, passive and/or active additional devices show that entering into an energetic power excursion as a consequence of the initiation phase of a ULOF cannot be avoided for those core designs with a cumulative void reactivity feedback larger than zero. However, even for core designs aiming at values of the void reactivity less than zero it is difficult to find system design characteristics which prevent the transient entering into partial core destruction. Further studies of the transient core and system behavior would require codes dedicated to specific aspects of transition phase analyses and of in-vessel material relocation analyses.

  8. Site investigation SFR. Rock type coding, overview geological mapping and identification of rock units and possible deformation zones in drill cores from the construction of SFR

    Energy Technology Data Exchange (ETDEWEB)

    Petersson, Jesper (Vattenfall Power Consultant AB, Stockholm (Sweden)); Curtis, Philip; Bockgaard, Niclas (Golder Associates AB (Sweden)); Mattsson, Haakan (GeoVista AB, Luleaa (Sweden))

    2011-01-15

    This report presents the rock type coding, overview lithological mapping and identification of rock units and possible deformation zones in drill cores from 32 boreholes associated with the construction of SFR. This work can be seen as complementary to single-hole interpretations of other older SFR boreholes earlier reported in /Petersson and Andersson 2010/: KFR04, KFR08, KFR09, KFR13, KFR35, KFR36, KFR54, KFR55, KFR7A, KFR7B and KFR7C. Due to deficiencies in the available material, the necessary activities have deviated somewhat from the established methodologies used during the recent Forsmark site investigations for the final repository for spent nuclear fuel. The aim of the current work has been, wherever possible, to allow the incorporation of all relevant material from older boreholes in the ongoing SFR geological modelling work in spite of the deficiencies. The activities include: - Rock type coding of the original geological mapping according to the nomenclature used during the preceding Forsmark site investigation. As part of the Forsmark site investigation such rock type coding has already been performed on most of the old SFR boreholes if the original geological mapping results were available. This earlier work has been complemented by rock type coding on two further boreholes: KFR01 and KFR02. - Lithological overview mapping, including documentation of (1) rock types, (2) ductile and brittle-ductile deformation and (3) alteration for drill cores from eleven of the boreholes for which no original geological borehole mapping was available (KFR31, KFR32, KFR34, KFR37,KFR38, KFR51, KFR69, KFR70, KFR71, KFR72 and KFR89). - Identification of possible deformation zones and merging of similar rock types into rock units. This follows SKB's established criteria and methodology of the geological Single-hole interpretation (SHI) process wherever possible. Deviations from the standard SHI process are associated with the lack of data, for example BIPS images

  9. Site investigation SFR. Boremap mapping of core drilled borehole KFR106

    Energy Technology Data Exchange (ETDEWEB)

    Winell, Sofia (Geosigma AB (Sweden))

    2010-06-15

    This report presents the result from the Boremap mapping of the core drilled borehole KFR106, drilled from an islet ca 220 m southeast of the pier above SFR. The borehole has a length of 300.13 m, and a bearing and inclination of 195.1 deg and -69.9 deg, respectively. The purpose of the location and orientation of the borehole is to investigate the possible occurrence of gently dipping, water-bearing structures in the area. The geological mapping is based on simultaneous study of drill core and borehole image (BIPS). The two lowermost meters of the drill core was mapped in Boremap without access to complementary BIPS-image. The dominating rock type, which occupies 72% of KFR106, is fine- to medium-grained, metagranite granodiorite (rock code 101057), which is foliated with a medium to strong intensity. Pegmatite to pegmatitic granite (rock code 101061) is the second most common rock type and it occupies 16% of the mapped interval. It is also frequent as smaller rock occurrences (< 1 m) in other rock types throughout the borehole. Subordinate rock types are fine- to medium-grained granite (rock code 111058), felsic to intermediate meta volcanic rock (rock code 103076), fine- to medium-grained metagranitoid (rock code 101051) and amphibolite (rock code 102017). Totally 49% of the rock in KFR106 has been mapped as altered, where muscovitization and oxidation is the two most common. Additional shorter intervals of alterations are in decreasing order of abundance quartz dissolution, epidotization, argillization, albitization, chloritization, laumontization and carbonatization. A total number of 2801 fractures are registered in KFR106. Of these are 1059 open, 1742 sealed and 84 partly open. This result in the following fracture frequencies: 6.0 sealed fractures/m, 3.7 open fractures/m and 0.3 partly open fractures/m. In addition there are 5 narrow brecciated zones, and 20 sealed networks with a total length of 18 m. The most frequent fracture fillings in KFR106 are

  10. Coupled analysis of core thermal hydraulics and fuel performance to evaluate a thermally induced fuel failure in an SFR subassembly

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sun Rock; Chang, Doo Soo; Kim, Sang Ji [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    A limiting factor analysis in a core thermal design is highly important to assure the safe and reliable operation of a reactor system. In a sodium cooled fast reactor (SFR), the coolant thermal conductivity is about hundreds of times larger than the thermal conductivity of water. Moreover, the coolant boiling temperature in an SFR is around 900 .deg. C, which is much higher than that of the water coolant in a PWR. Considering typical operating temperatures, an SFR has about a 300 .deg. C thermal margin to its boiling point. Therefore, instead of DNBR (Departure from Nucleate Boiling Ratio) in a PWR, the core thermal design of SFRs requires assuring proper fuel performance and safety, where the design limits are highly related to the temperature distribution and material behavior under various operating conditions. Typical limiting factors in SFRs are the thermal component of the plastic hoop strain, radial primary hoop stress, and cumulative damage factor during normal operation. However, the previous fuel performance codes only evaluate a single fuel pin performance, which neglects the radial peaking factors and reveals too conservative results. In this work, the multi physics analysis is performed using both thermalhydraulic and fuel performance codes.

  11. Moderating Material to Compensate the Drawback of High Minor Actinide Containing Transmutation Fuel on the Feedback Effects in SFR Cores

    Directory of Open Access Journals (Sweden)

    Bruno Merk

    2013-01-01

    Full Text Available The use of fine distributed moderating material to enhance the feedback effects and to reduce the sodium void effecting SFRs is described. The drawback on the feedback effects due to the introduction of minor actinides into SFR fuel is analyzed. The possibility of compensation of the effect of the minor actinides on the feedback effects by the use of fine distributed moderating material is demonstrated. The consequences of the introduction of fine distributed moderating material into fuel assemblies with fuel configurations foreseen for minor actinide transmutation are analyzed, and the positive effects on the transmutation efficiency are shown. Finally, the possible increase of the Americium content to improve the transmutation efficiency is discussed, the limit value of Americium is determined, and the possibilities given by an increase of the hydrogen content are analyzed.

  12. Behavior of an heterogeneous annular FBR core during an unprotected loss of flow accident: Analysis of the primary phase with SAS-SFR

    Energy Technology Data Exchange (ETDEWEB)

    Massara, S.; Schmitt, D.; Bretault, A.; Lemasson, D.; Darmet, G.; Verwaerde, D. [EDF R and D, 1, Avenue du General de Gaulle, 92141 Clamart (France); Struwe, D.; Pfrang, W.; Ponomarev, A. [Karlsruher Institut fuer Technologie KIT, Institut fuer Neutronenphysik und Reaktortechnik INR, Hermann-von-Helmholtz-Platz 1, Gebaude 521, 76344 Eggenstein-Leopoldshafen (Germany)

    2012-07-01

    In the framework of a substantial improvement on FBR core safety connected to the development of a new Gen IV reactor type, heterogeneous core with innovative features are being carefully analyzed in France since 2009. At EDF R and D, the main goal is to understand whether a strong reduction of the Na-void worth - possibly attempting a negative value - allows a significant improvement of the core behavior during an unprotected loss of flow accident. Also, the physical behavior of such a core is of interest, before and beyond the (possible) onset of Na boiling. Hence, a cutting-edge heterogeneous design, featuring an annular shape, a Na-plena with a B{sub 4}C plate and a stepwise modulation of fissile core heights, was developed at EDF by means of the SDDS methodology, with a total Na-void worth of -1 $. The behavior of such a core during the primary phase of a severe accident, initiated by an unprotected loss of flow, is analyzed by means of the SAS-SFR code. This study is carried-out at KIT and EDF, in the framework of a scientific collaboration on innovative FBR severe accident analyses. The results show that the reduction of the Na-void worth is very effective, but is not sufficient alone to avoid Na-boiling and, hence, to prevent the core from entering into the primary phase of a severe accident. Nevertheless, the grace time up to boiling onset is greatly enhanced in comparison to a more traditional homogeneous core design, and only an extremely low fraction of the fuel (<0.1%) enters into melting at the end of this phase. A sensitivity analysis shows that, due to the inherent neutronic characteristics of such a core, the gagging scheme plays a major role on the core behavior: indeed, an improved 4-zones gagging scheme, associated with an enhanced control rod drive line expansion feed-back effect, finally prevents the core from entering into sodium boiling. This major conclusion highlights both the progress already accomplished and the need for more detailed

  13. Sodium-cooled fast reactor (SFR) fuel assembly design with graphite-moderating rods to reduce the sodium void reactivity coefficient

    Energy Technology Data Exchange (ETDEWEB)

    Won, Jong Hyuck; Cho, Nam Zin, E-mail: nzcho@kaist.ac.kr; Park, Hae Min; Jeong, Yong Hoon, E-mail: jeongyh@kaist.ac.kr

    2014-12-15

    Highlights: • The graphite rod-inserted SFR fuel assembly is proposed to achieve low sodium void reactivity. • The neutronics/thermal-hydraulics analyses are performed for the proposed SFR cores. • The sodium void reactivity is improved about 960–1030 pcm compared to reference design. - Abstract: The concept of a graphite-moderating rod-inserted sodium-cooled fast reactor (SFR) fuel assembly is proposed in this study to achieve a low sodium void reactivity coefficient. Using this concept, two types of SFR cores are analyzed; the proposed SFR type 1 core has new SFR fuel assemblies at the inner/mid core regions while the proposed SFR type 2 core has a B{sub 4}C absorber sandwich in the middle of the active core region as well as new SFR fuel assemblies at the inner/mid core regions. For the proposed SFR core designs, neutronics and thermal-hydraulic analyses are performed using the DIF3D, REBUS3, and the MATRA-LMR codes. In the neutronics analysis, the sodium void reactivity coefficient is obtained in various void situations. The two types of proposed core designs reduce the sodium void reactivity coefficient by about 960–1030 pcm compared to the reference design. However, the TRU enrichment for the proposed SFR core designs is increased. In the thermal hydraulic analysis, the temperature distributions are calculated for the two types of proposed core designs and the mass flow rate is optimized to satisfy the design constraints for the highest power generating assembly. The results of this study indicate that the proposed SFR assembly design concept, which adopts graphite-moderating rods which are inserted into the fuel assembly, can feasibly minimize the sodium void reactivity coefficient. Single TRU enrichment and an identical fuel slug diameter throughout the SFR core are also achieved because the radial power peak can be flattened by varying the number of moderating rods in each core region.

  14. SFR site investigation. Bedrock Hydrogeochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Ann-Chatrin [Geosigma AB, Uppsala (Sweden); Tullborg, Eva-Lena [Terralogica AB, Graabo (Sweden); Smellie, John [Conterra AB, Uppsala (Sweden); Gimeno, Maria J.; Gomez, Javier B.; Auque, Luis F. [Univ. of Zaragoza, Zaragoza (Spain); Sandstroem, Bjoern [WSP Sverige AB, Goeteborg (Sweden); Pedersen, Karsten [Micans AB, Moelnlycke (Sweden)

    2011-11-15

    There are plans that the final repository for low and intermediate level radioactive waste, SFR, located about 150 km north of Stockholm, will be extended. Geoscientific studies to define and characterise a suitable bedrock volume for the extended repository have been carried out from 2007 to 2011, and have included the drilling and evaluation of seven new core drilled and four percussion boreholes. These new data, together with existing data extending back to 1985, have been interpreted and modelled in order to provide the necessary information for safety assessment and repository design. This report presents the final hydrogeochemical site description for the SFR site, and will constitute a background report for the integrated site description (the SFR Site Descriptive Model version 1.0) together with corresponding reports from the geological and hydrogeological disciplines. Most of the hydrogeochemical data from the field investigations consist of major ions and isotopes together with sporadic gas, microbe and measured redox data. Despite the close proximity of the Forsmark site, few data from this source are of relevance because of the shallow nature of the SFR site, the fact that SFR is located beneath the Baltic Sea and also the drawdown/upconing impacts of its construction on the hydrogeochemistry. This artificially imposed dynamic flow system is naturally more prevalent along major deformation fracture zones of higher transmissivity, whilst lower transmissive fractures together with the less transmissive bedrock masses between major deformation zones, still retain some evidence of the natural groundwater mixing patterns established prior to the SFR construction. The groundwaters in the SFR dataset cover a depth down to -250 m.a.s.l. with single sampling locations at -300 and -400 m.a.s.l. and represent a relatively limited salinity range (1,500 to 5,500 mg/L chloride). However, the {delta}{sup 18}O values show a wide variation (-15.5 to -7.5 per mille V

  15. SFR site investigation. Bedrock Hydrogeochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Ann-Chatrin [Geosigma AB, Uppsala (Sweden); Tullborg, Eva-Lena [Terralogica AB, Graabo (Sweden); Smellie, John [Conterra AB, Uppsala (Sweden); Gimeno, Maria J.; Gomez, Javier B.; Auque, Luis F. [Univ. of Zaragoza, Zaragoza (Spain); Sandstroem, Bjoern [WSP Sverige AB, Goeteborg (Sweden); Pedersen, Karsten [Micans AB, Moelnlycke (Sweden)

    2011-11-15

    There are plans that the final repository for low and intermediate level radioactive waste, SFR, located about 150 km north of Stockholm, will be extended. Geoscientific studies to define and characterise a suitable bedrock volume for the extended repository have been carried out from 2007 to 2011, and have included the drilling and evaluation of seven new core drilled and four percussion boreholes. These new data, together with existing data extending back to 1985, have been interpreted and modelled in order to provide the necessary information for safety assessment and repository design. This report presents the final hydrogeochemical site description for the SFR site, and will constitute a background report for the integrated site description (the SFR Site Descriptive Model version 1.0) together with corresponding reports from the geological and hydrogeological disciplines. Most of the hydrogeochemical data from the field investigations consist of major ions and isotopes together with sporadic gas, microbe and measured redox data. Despite the close proximity of the Forsmark site, few data from this source are of relevance because of the shallow nature of the SFR site, the fact that SFR is located beneath the Baltic Sea and also the drawdown/upconing impacts of its construction on the hydrogeochemistry. This artificially imposed dynamic flow system is naturally more prevalent along major deformation fracture zones of higher transmissivity, whilst lower transmissive fractures together with the less transmissive bedrock masses between major deformation zones, still retain some evidence of the natural groundwater mixing patterns established prior to the SFR construction. The groundwaters in the SFR dataset cover a depth down to -250 m.a.s.l. with single sampling locations at -300 and -400 m.a.s.l. and represent a relatively limited salinity range (1,500 to 5,500 mg/L chloride). However, the {delta}{sup 18}O values show a wide variation (-15.5 to -7.5 per mille V

  16. Site investigation SFR. Bedrock geology

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, Philip; Markstroem, Ingemar (Golder Associates AB (Sweden)); Petersson, Jesper (Vattenfall Power Consultant AB (Sweden)); Triumf, Carl-Axel; Isaksson, Hans; Mattsson, Haakan (GeoVista AB (Sweden))

    2011-12-15

    the geological tunnel mapping and eleven drill cores remapped according to the Boremap system, input to model version 1.0 has included the results from eight new cored boreholes as well as a fuller integration of Forsmark site investigation data, a further more extensive review of the drill core from an additional 32 boreholes associated with the construction of the existing SFR facility and an updated mapping of the lower construction tunnel. The current modelling work has also reviewed the older SFR data and models. While details concerning the earlier zones lying in immediate contact with the existing SFR facility have been changed, the earlier overall position, orientation and number of these deformation zones is maintained. A significant difference concerns their thickness due to the contrasting methodologies used during the different campaigns. In SFR model version 0.1, a single deformation zone model was produced, with a volume corresponding to the regional model volume. The model contained all the deformation zones modelled irrespective of size. Separate local and regional deformation zone models have been produced in SFR model version 1.0, following resolution criteria for the different model volumes. The local model contains zones with a minimum size of 300 m, while the regional model has structures that have a minimum size constraint of 1,000 m trace length at the ground surface. The selection of these size limits is related to the model volume maximum depth (local model -300 masl and regional model -1,000 masl) and the applied methodology that requires the same model resolution throughout the defined model volume (see Section 5.3.1). To assist hydrogeological modelling work, an updated combined model, including all structures from both the regional and local models, has also been delivered. The existing SFR facility and the rock volume directly to the south-east, which is proposed for the new facility extension, lies within a tectonic block that is bounded

  17. Site investigation SFR. Bedrock geology

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, Philip; Markstroem, Ingemar (Golder Associates AB (Sweden)); Petersson, Jesper (Vattenfall Power Consultant AB (Sweden)); Triumf, Carl-Axel; Isaksson, Hans; Mattsson, Haakan (GeoVista AB (Sweden))

    2011-12-15

    the geological tunnel mapping and eleven drill cores remapped according to the Boremap system, input to model version 1.0 has included the results from eight new cored boreholes as well as a fuller integration of Forsmark site investigation data, a further more extensive review of the drill core from an additional 32 boreholes associated with the construction of the existing SFR facility and an updated mapping of the lower construction tunnel. The current modelling work has also reviewed the older SFR data and models. While details concerning the earlier zones lying in immediate contact with the existing SFR facility have been changed, the earlier overall position, orientation and number of these deformation zones is maintained. A significant difference concerns their thickness due to the contrasting methodologies used during the different campaigns. In SFR model version 0.1, a single deformation zone model was produced, with a volume corresponding to the regional model volume. The model contained all the deformation zones modelled irrespective of size. Separate local and regional deformation zone models have been produced in SFR model version 1.0, following resolution criteria for the different model volumes. The local model contains zones with a minimum size of 300 m, while the regional model has structures that have a minimum size constraint of 1,000 m trace length at the ground surface. The selection of these size limits is related to the model volume maximum depth (local model -300 masl and regional model -1,000 masl) and the applied methodology that requires the same model resolution throughout the defined model volume (see Section 5.3.1). To assist hydrogeological modelling work, an updated combined model, including all structures from both the regional and local models, has also been delivered. The existing SFR facility and the rock volume directly to the south-east, which is proposed for the new facility extension, lies within a tectonic block that is bounded

  18. Trade-off study on the power capacity of a prototype SFR in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Baek, M. H.; Kim, S. J.; Yoo, J.; Bae, I. H. [Korea Atomic Energy Research Inst., 1045 Daedeog-daero, Yuseong-gu, 305-353 Daejeon (Korea, Republic of)

    2012-07-01

    The major roles of a prototype SFR are to provide irradiation test capability for the fuel and structure materials, and to obtain operational experiences of systems. Due to a compromise between the irradiation capability and construction costs, the power level should be properly determined. In this paper, a trade-off study on the power level of the prototype SFR was performed from a neutronics viewpoint. To select candidate cores, the parametric study of pin diameters was estimated using 20 wt.% uranium fuel. The candidate cores of different power levels, 125 MWt, 250 MWt, 400 MWt, and 500 MWt, were compared with the 1500 MWt reference core. The resulting core performance and economic efficiency indices became insensitive to the power at about 400-500 MWt and sharply deteriorated at about 125-250 MWt with decreasing core sizes. Fuel management scheme, TRU core performance comparing with uranium core, and sodium void reactivity were also evaluated with increasing power levels. It is found that increasing the number of batches showed higher burnup performance and economic efficiency. However, increasing the cycle length showed the trends in lower economic efficiency. Irradiation performance of TRU and enriched TRU cores was improved about 20 % and 50 %, respectively. The maximum sodium void reactivity of 5.2$ was confirmed less than the design limit of 7.5$. As a result, the power capacity of the prototype SFR should not be less than 250 MWt and would be appropriate at {approx} 500 MWt considering the performance and economic efficiency. (authors)

  19. On recent SFR calibrations and the constant SFR approximation

    CERN Document Server

    Cervino, M; Hidalgo, S

    2016-01-01

    Star Formation Rate (SFR) inferences are based in the so-called constant SFR approximation, where synthesis models are require to provide a calibration; we aims to study the key points of such approximation to produce accurate SFR inferences. We use the intrinsic algebra used in synthesis models, and we explore how SFR can be inferred from the integrated light without any assumption about the underling Star Formation history (SFH). We show that the constant SFR approximation is actually a simplified expression of more deeper characteristics of synthesis models: It is a characterization of the evolution of single stellar populations (SSPs), acting the SSPs as sensitivity curve over different measures of the SFH can be obtained. As results, we find that (1) the best age to calibrate SFR indices is the age of the observed system (i.e. about 13Gyr for z=0 systems); (2) constant SFR and steady-state luminosities are not requirements to calibrate the SFR; (3) it is not possible to define a SFR single time scale ove...

  20. Optimizing SFR transmutation performance through direct adjoining control theory

    Science.gov (United States)

    Davis, Jeffrey C.

    2007-12-01

    We have developed the CORTANA code to optimize the transmutation performance of sodium cooled fast reactors (SFRs). We obtain the necessary conditions for optimal fuel and burnable absorber loadings using Pontryagin's maximum principle with a direct adjoining approach to explicitly account for either a flat flux or a power peaking inequality constraint providing a set of coupled system, Euler-Lagrange (E-L), and optimality equations which are iteratively solved with the method of conjugate gradients until no further improvement in the objective function is achieved. To satisfy the inequality constraints throughout the operating cycle, we have implemented a backwards diffusion theory (BDT) to establish a relationship between fuel loading and the relative assembly power distribution during the cycle and systematically eliminate the constraint violations with each conjugate gradient iteration. The CORTANA SFR optimization code uses multi-group, three-dimensional neutron diffusion theory, with a microscopic depletion scheme. We solve the system equations in a quasi-static fashion forward in time from beginning-of-cycle (BOC) to end-of-cycle (EOC), while we solve the E-L equations backwards in time from EOC to BOC, reflecting the adjoint nature of the Lagrange multipliers. A two enrichment-zone SFR problem verifies our formulation, yielding a TRU enrichment distribution nearly identical to that of the reference SFR core in the Generation IV Roadmap. Using a full heavy metal recycling mode, we coupled our optimization methodology with the REBUS-3 equilibrium cycle methodology to optimize an SFR operating as a second tier transmuter. We model the system using a three-dimensional triangular-z finite differencing scheme with full core symmetry and a time-independent 33-group microscopic cross section library. Beginning from a uniform TRU distribution, our CORTANA improves the SFR performance by reducing the maximum relative assembly power from 1.7 to 1.25, minimizes

  1. Physico-statistical approach to assess the core damage variability due to a total instantaneous blockage of SFR fuel sub-assembly

    Energy Technology Data Exchange (ETDEWEB)

    Marie, N., E-mail: nathalie.marie@cea.fr [CEA, DEN, DER, Saint Paul Lez Durance, F-13108 (France); Marrel, A. [CEA, DEN, DER, Saint Paul Lez Durance, F-13108 (France); Seiler, J.M. [CEA, DEN, DTN, Grenoble, F-38054 (France); Bertrand, F. [CEA, DEN, DER, Saint Paul Lez Durance, F-13108 (France)

    2016-02-15

    Highlights: • Physico-statistical tool for SFR safety for Total Instantaneous Blockage accident. • 0D/1D but realistic physical models to describe the phenomenological event tree. • Twenty-seven uncertain parameters identified to cover all realistic accidental transients. • Uncertainty propagation performed via a Monte-Carlo sampling. • Quantification of safety margins: 18.1% of cases above the safety criterion. - Abstract: Within the framework of the generation IV Sodium Fast Reactors (SFR) R&D program of CEA (French commissariat à l’énergie atomique et aux énergies alternatives), the safety in case of accidents is assessed. These accidental scenarios involve very complex transient phenomena. To get round the difficulty of modelling them, only ‘Bounding’ (most damaging) accidental conditions have been up to now studied for the safety demonstration. These transients are simulated with very complex multi-physical codes (such as SIMMER) which nevertheless include some adjusted and not well known parameters and require a long CPU (process) time preventing their direct use for uncertainty propagation and sensitivity studies, especially in case of a high number of uncertain input parameters. To cope with these constraints, a new physico-statistical approach is followed in parallel by the CEA. This approach involves the fast-running description of extended accident sequences coupling analytical models for the main physical phenomena in combination with advanced statistical analysis techniques. The efficiency of the methodology for the reactor safety analysis is demonstrated here for one type of accident – the Total Instantaneous Blockage (TIB) – which involves an extended range of complex physical phenomena. From the establishment of the physical models describing the TIB phenomenology, 27 uncertain input parameters and their associated probability distributions are identified. A propagation of these input parameter uncertainties is performed via a

  2. The nuclide inventory in SFR-1; Nuklidinventariet i SFR-1

    Energy Technology Data Exchange (ETDEWEB)

    Ingemansson, Tor [ALARA Engineering, Skultuna (Sweden)

    2001-10-01

    This report is an account for a project carried out on behalf of the Swedish Radiation Protection Authority (SSI): 'Nuclide inventory in SFR-1' (The Swedish underground disposal facility for low and intermediate level reactor waste). The project comprises the following five sub-projects: 1) Measuring methods for nuclides, difficult to measure, 2) The nuclide inventory in SFR-1, 3) Proposal for nuclide library for SFR-1 and ground disposal, 4) Nuclide library for exemption, and 5) Characterising of the nuclide inventory and documentation for SFL waste. In all five sub-projects long-lived activity, including Cl-36, has been considered.

  3. Improved spectral energy distribution fitting of galaxies at 1 < z <3.5 in the SFR-M* plane and their morphological properties

    Science.gov (United States)

    Lee, Bomee; Giavalisco, M.; Acquaviva, V.; CANDELS Collaboration

    2014-01-01

    In the star formation rate (SFR) - stellar mass (M*) diagram, galaxies can be separated in four different populations: starbursts which lie above the main sequence of star formation (MS), normal star-forming galaxies on the tight MS, galaxies below the MS with a little star-forming activity and quiescent galaxies. Renzini (2009) suggested that galaxies on, above and below the MS follow very different time evolution of SFR. We test this idea with large samples of galaxies at 1 histories (SFH) for galaxies in the four different populations. We further study correlations and trends between the morphology of the galaxies and their positions relative to the MS using non-parametric (Sersic index) and parametric measures as well as the visual identification. We also explore the effects on the rest-frame colors of dust obscuration to constrain the slope and the scatter on the MS.

  4. Site investigation SFR. Overview Boremap mapping of drill cores from KFR04, KFR08, KFR09, KFR13, KFR35, KFR36, KFR54, KFR55, KFR7A, KFR7B and KFR7C

    Energy Technology Data Exchange (ETDEWEB)

    Petersson, Jesper; Andersson, Ulf B. (Vattenfall Power Consultant AB, Stockholm (Sweden))

    2011-01-15

    This report presents the results from a renewed geological overview mapping of 11 drill cores obtained during the construction of the final repository for low and middle level radioactive operational waste (SFR) during the 80's. Drill cores from KFR04, KFR08, KFR09, KFR13, KFR35, KFR36, KFR54, KFR55, KFR7A, KFR7B and KFR7C, with a total length of 837 m, was selected primarily because of their distinctly crosscutting relationship with inferred deformation zones in the area. The main purpose for this geological mapping is calibration with the original mappings, which in turn aims to facilitate geological single-hole interpretation. The mapping was generally focused on the location and infilling mineralogy of broken and unbroken fractures, as well as crush zones, breccias and sealed networks. Also the overview lithology, alterations and ductile shear zones were documented. All boreholes selected for renewed mapping are located in a ductile, high-strain belt, which defines the northeastern margin of a structurally more homogeneous tectonic lens. The main component of the high-strain belt is felsic to intermediate rocks of inferred volcanic origin. The predominant rock in the selected drill cores is, however, a fine- to finely medium-grained metagranite, which clearly appears to be a high-strain variety of the typically medium-grained metagranite-granodiorite that prevails the tectonic lens. It is obvious that varieties of this high-strain rock previously was inferred to be meta volcanic rocks. Other volumetrically important rock types in the drill cores are pegmatitic granite, finely medium-grained granite and metagranodiorite-tonalite, aplitic metagranite, amphibolites and slightly coarser metagabbros. Virtually all rocks in the borehole have experienced Svecofennian metamorphism under amphibolite facies conditions. Excluding fractures within crush zones and sealed networks, there is a predominance of broken fractures in most of the drill cores. The total

  5. Conceptual study of reactor control and shutdown rod drive mechanism of a SFR

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Han; Kim, Jong Bum

    2012-09-15

    The conceptual design of a prototype SFR (sodium cooled Fast Reactor) of 150MWe capacity was began in 2012 through the Korea national long term R and D project by KAERI. This report describes the design concepts of a control rod drive mechanism for plant control system and a passive shutdown rod drive mechanism for reactor protection system of a SFR. The performance requirements and preliminary design values of the core power control rod drive mechanism are determined based on the KALIMER 600 and PRISM design concepts. As for the scram rod drive mechanism, several types of passive shutdown systems are introduced, several candidate design concepts are proposed and the reactor shutdown rod drive mechanism is described shortly. This report also performs the parametric design studies for the electromagnet component of the passive shutdown device. Its design feasibility is investigated for a given design installation constraint, and the necessary items for design improvements to meet the design requirements are suggested.

  6. 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

  7. Site investigation SFR. Hydrogeological modelling of SFR. Model version 0.2

    Energy Technology Data Exchange (ETDEWEB)

    Oehman, Johan (Golder Associates AB (Sweden)); Follin, Sven (SF GeoLogic (Sweden))

    2010-01-15

    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). A hydrogeological model is developed in three model versions, which will be used for safety assessment and design analyses. This report presents a data analysis of the currently available hydrogeological data from the ongoing Site Investigation SFR (KFR27, KFR101, KFR102A, KFR102B, KFR103, KFR104, and KFR105). The purpose of this work is to develop a preliminary hydrogeological Discrete Fracture Network model (hydro-DFN) parameterisation that can be applied in regional-scale modelling. During this work, the Geologic model had not yet been updated for the new data set. Therefore, all analyses were made to the rock mass outside Possible Deformation Zones, according to Single Hole Interpretation. Owing to this circumstance, it was decided not to perform a complete hydro-DFN calibration at this stage. Instead focus was re-directed to preparatory test cases and conceptual questions with the aim to provide a sound strategy for developing the hydrogeological model SFR v. 1.0. The presented preliminary hydro-DFN consists of five fracture sets and three depth domains. A statistical/geometrical approach (connectivity analysis /Follin et al. 2005/) was performed to estimate the size (i.e. fracture radius) distribution of fractures that are interpreted as Open in geologic mapping of core data. Transmissivity relations were established based on an assumption of a correlation between the size and evaluated specific capacity of geologic features coupled to inflows measured by the Posiva Flow Log device (PFL-f data). The preliminary hydro-DFN was applied in flow simulations in order to test its performance and to explore the role of PFL-f data. Several insights were gained and a few model technical issues were raised. These are summarised in Table 5-1

  8. Metallic Reactor Fuel Fabrication for SFR

    Energy Technology Data Exchange (ETDEWEB)

    Song, Hoon; Kim, Jong-Hwan; Ko, Young-Mo; Woo, Yoon-Myung; Kim, Ki-Hwan; Lee, Chan-Bock [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    The metal fuel for an SFR has such advantages such as simple fabrication procedures, good neutron economy, high thermal conductivity, excellent compatibility with a Na coolant, and inherent passive safety 1. U-Zr metal fuel for SFR is now being developed by KAERI as a national R and D program of Korea. The fabrication technology of metal fuel for SFR has been under development in Korea as a national nuclear R and D program since 2007. The fabrication process for SFR fuel is composed of (1) fuel slug casting, (2) loading and fabrication of the fuel rods, and (3) fabrication of the final fuel assemblies. Fuel slug casting is the dominant source of fuel losses and recycled streams in this fabrication process. Fabrication on the rod type metallic fuel was carried out for the purpose of establishing a practical fabrication method. Rod-type fuel slugs were fabricated by injection casting. Metallic fuel slugs fabricated showed a general appearance was smooth.

  9. Preliminary Hydrogeochemical Site Description SFR (version 0.2)

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Ann-Chatrin (Geosigma AB, Uppaala (Sweden)); Tullborg, Eva-Lena (Terralogica AB, Graabo (Sweden)); Smellie, John (Conterra AB, Partille (Sweden))

    2010-05-15

    The final repository for low and intermediate level radioactive operational waste, SFR, located about 150 km north of Stockholm, is to undergo a future extension. The present on-going project, scheduled from 2007 to 2011, is to define and characterise a suitable bedrock volume for the extended repository. This will include the drilling and geoscientific evaluation of seven core-drilled and four percussion boreholes as well as subsequent interpretation and modelling based on the obtained results in order to provide the necessary information for safety assessment and repository design. This report presents a preliminary hydrogeochemical site description for the SFR site and should be considered as an early progress report rather than a complete hydrochemical site descriptive model. The completed hydrogeochemical field investigations have yielded chemical data from a total of 12 borehole sections in five boreholes and additional data from the entire length of two open boreholes in connection with hydraulic tests. These data, together with data from a total of 18 early boreholes in the present SFR tunnel system, were used in the interpretation work. The main part of the data consisted of basic groundwater analyses including major ions and isotopes. Some sporadic gas, microbe and measured redox data are available, but these are either not treated in this report, or are only briefly discussed. This was due to time constraints since special care is needed when interpreting few data of varying quality. The groundwaters in the SFR dataset cover a maximum depth down to about .400 masl and represent a relatively limited salinity range (1,500 to 5,500 mg/L chloride). However, the delta18O values show a wide variation (-1.55 to -0.75% V-SMOW) similar to that reported from the Forsmark site investigations. At the SFR, marine indicators such as Mg/Cl, K/Cl and Br/Cl also show relatively large variations considering the limited salinity range. From very few measured Eh values, and

  10. Dose assessments for SFR 1

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, Ulla (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)); Avila, Rodolfo; Ekstroem, Per-Anders; Cruz, Idalmis de la (Facilia AB, Bromma (Sweden))

    2008-06-15

    Following a review by the Swedish regulatory authorities of the safety analysis of the SFR 1 disposal facility for low and intermediate level waste, SKB has prepared an updated safety analysis, SAR-08. This report presents estimations of annual doses to the most exposed groups from potential radionuclide releases from the SFR 1 repository for a number of calculation cases, selected using a systematic approach for identifying relevant scenarios for the safety analysis. The dose estimates can be used for demonstrating that the long term safety of the repository is in compliance with the regulatory requirements. In particular, the mean values of the annual doses can be used to estimate the expected risks to the most exposed individuals, which can then be compared with the regulatory risk criteria for human health. The conversion from doses to risks is performed in the main report. For one scenario however, where the effects of an earthquake taking place close to the repository are analysed, risk calculations are presented in this report. In addition, prediction of concentrations of radionuclides in environmental media, such as water and soil, are compared with concentration limits suggested by the Erica-project as a base for estimating potential effects on the environment. The assessment of the impact on non-human biota showed that the potential impact is negligible. Committed collective dose for an integration period of 10,000 years for releases occurring during the first thousand years after closure are also calculated. The collective dose commitment was estimated to be 8 manSv. The dose calculations were carried out for a period of 100,000 years, which was sufficient to observe peak doses in all scenarios considered. Releases to the landscape and to a well were considered. The peaks of the mean annual doses from releases to the landscape are associated with C-14 releases to a future lake around year 5,000 AD. In the case of releases to a well, the peak annual doses

  11. Dose assessments for SFR 1

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, Ulla (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)); Avila, Rodolfo; Ekstroem, Per-Anders; Cruz, Idalmis de la (Facilia AB, Bromma (Sweden))

    2008-06-15

    Following a review by the Swedish regulatory authorities of the safety analysis of the SFR 1 disposal facility for low and intermediate level waste, SKB has prepared an updated safety analysis, SAR-08. This report presents estimations of annual doses to the most exposed groups from potential radionuclide releases from the SFR 1 repository for a number of calculation cases, selected using a systematic approach for identifying relevant scenarios for the safety analysis. The dose estimates can be used for demonstrating that the long term safety of the repository is in compliance with the regulatory requirements. In particular, the mean values of the annual doses can be used to estimate the expected risks to the most exposed individuals, which can then be compared with the regulatory risk criteria for human health. The conversion from doses to risks is performed in the main report. For one scenario however, where the effects of an earthquake taking place close to the repository are analysed, risk calculations are presented in this report. In addition, prediction of concentrations of radionuclides in environmental media, such as water and soil, are compared with concentration limits suggested by the Erica-project as a base for estimating potential effects on the environment. The assessment of the impact on non-human biota showed that the potential impact is negligible. Committed collective dose for an integration period of 10,000 years for releases occurring during the first thousand years after closure are also calculated. The collective dose commitment was estimated to be 8 manSv. The dose calculations were carried out for a period of 100,000 years, which was sufficient to observe peak doses in all scenarios considered. Releases to the landscape and to a well were considered. The peaks of the mean annual doses from releases to the landscape are associated with C-14 releases to a future lake around year 5,000 AD. In the case of releases to a well, the peak annual doses

  12. RISK-INFORMED BALANCING OF SAFETY, NONPROLIFERATION, AND ECONOMICS FOR THE SFR

    Energy Technology Data Exchange (ETDEWEB)

    Apostolakis, George; Driscoll, Michael; Golay, Michael; Kadak, Andrew; Todreas, Neil; Aldmir, Tunc; Denning, Richard; Lineberry, Michael

    2011-10-20

    , particularly concerning seismic and aircraft impactrelated risks. Most importantly, within the context of the TNF historical SFR safety concerns about energetic core disruptive accidents are seen to be unimportant, but those of rare scenarios mentioned above are seen to be of dominant concern. In terms of proliferation risks the SFR energy system is seen not to be of considerably greater concern than with other nuclear power technologies, providing that highly effective safeguards are employed. We find the economic performance of proposed SFRs likely, due to the problems of using sodium as a coolant, to be inferior to those of LWRs unless they can be credited for services to improve nuclear waste disposal, nuclear fuel utilization and proliferation risk reductions. None of the design innovations investigated offers the promise to reverse this conclusion. The most promising innovation investigated is that of improving the plant's thermodynamic efficiency via use of the supercritical CO{sub 2} (rather than steam Rankine) power conversion system. We were unable to reach conclusions about the economic and proliferation risk implications of competing nuclear fuel processing methods, as available designs are too little developed to justify any such results. Overall, we find the SFR to be a promising alternative to LWRs should the conditions governing the valuation change substantially from current ones.

  13. Core skills assessment to improve mathematical competency

    Science.gov (United States)

    Carr, Michael; Bowe, Brian; Fhloinn, Eabhnat Ní

    2013-12-01

    Many engineering undergraduates begin third-level education with significant deficiencies in their core mathematical skills. Every year, in the Dublin Institute of Technology, a diagnostic test is given to incoming first-year students, consistently revealing problems in basic mathematics. It is difficult to motivate students to address these problems; instead, they struggle through their degree, carrying a serious handicap of poor core mathematical skills, as confirmed by exploratory testing of final year students. In order to improve these skills, a pilot project was set up in which a 'module' in core mathematics was developed. The course material was basic, but 90% or higher was required to pass. Students were allowed to repeat this module throughout the year by completing an automated examination on WebCT populated by a question bank. Subsequent to the success of this pilot with third-year mechanical engineering students, the project was extended to five different engineering programmes, across three different year-groups. Full results and analysis of this project are presented, including responses to interviews carried out with a selection of the students involved.

  14. Characterisation of bitumenised waste in SFR 1

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Michael; Elert, M. [Kemakta Konsult AB, Stockholm (Sweden)

    2001-06-01

    The waste deposited in the Final Repository for Radioactive Operational Waste, SFR, consists in part of waste solidified in bitumen. Bitumen is considered to have favourable chemical and physical properties to act as a fixation material for radioactive waste. However, during interim storage and subsequent disposal bitumen's properties may change. This may influence the stability of the bitumen matrix to retain radionuclides. This report discusses different processes affecting the long-term performance of bitumenised waste, and an evaluation of these properties in waste deposited in SFR 1 is made. The possible effect of a bitumen barrier on the release rate of radionuclides from SFR 1 is assessed. Based on leaching experiments reviewed in this study, it could take some thousand years, possibly more, to release all radionuclides in a 200-litre drum. The results are, however, extrapolated from experiments performed during a short period of time. Long- term deteriorating effects and the effect of a low temperature on the bitumen matrix are not very well documented. The literature focuses principally on bitumenised evaporator concentrate, but the bitumenised waste deposited in SFR 1 consists mainly of ion exchange resins. There are indications that the non-radioactive waste products usually investigated overestimate bitumen's ability to retain waste. Radiolytic effects has been estimated in this work to be negligible for waste categories F.17, F.20 and B.20 deposited in SFR 1, but for categories B.05, B.06 and F.18 the possibility of increased water uptake rate due to radiolysis can not be excluded. A more reasonable assumption is that bitumen will act as an effective barrier for radionuclide release during a time span from some hundreds to thousand of years. Generally, the majority of the inventory of radionuclides in SFR 1 is not solidified in bitumen. By taking the bitumen barrier into account in the modelling of release of radio- nuclides from SFR 1, the

  15. Applicability of Various Fuel Forms with TRU for Small SFR

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Tae-Yang; Kim, Myung Hyun [Kyung Hee Univ., Yongin (Korea, Republic of)

    2014-10-15

    The metallic fuel has been used commonly in sodium cooled fast reactor (SFR). It is known as a well-suited fuel form for SFR because of high theoretical density, high thermal conductivity and harder neutron spectrum. These advantages make metal fuel be used for EBR-II from the early R-D ages even though its own limits including reprocessing problems. On the other hand the oxide fuel developed for LWRs has benefits of huge operational experiences and database. The core performance and safety features of small sized reactor are different with larger sized reactor because of larger neutron leakage. Especially, it is expected to reduce positive sodium void effect or make negative due to larger effect of neutron leakage than spectral hardening effect. However, the importance of each control rod is very high because of a few control rods. Detail calculation for rod worth should be cared for the safety against rod withdrawal accidents. The prototype SFR which is named PGSFR has been planned to be constructed in the Rep. of Korea. The effective cross sections, weighted region-wise flux, are made by TRANSX and DANTSYS (with TWODANT module) and burnup calculation of core is done by REBUS (with DIF3D module). MCNPX code is partially used such as calculation of effective delayed neutron fraction. The code validation for small SFR with TRANSXDANTSYS- REBUS code system was done at the previous studies. The core performance characteristics and safety analysis for small sized SFR with metallic, oxide and nitride fuel with TRU are performed by calculation of reactivity coefficient, shutdown margin and quasi-static analysis. The theoretical density of oxide fuel is relatively low therefore its TRU fraction in heavy metal is relatively higher than others. For nitride fuel, the TRU fraction in heavy metal is relatively lower than others due to higher theoretical density and higher smear density. In the aspect of core performance, all of the fuel options are shown similar power peaking

  16. Improving Core Strength to Prevent Injury

    Science.gov (United States)

    Oliver, Gretchen D.; Adams-Blair, Heather R.

    2010-01-01

    Regardless of the sport or skill, it is essential to have correct biomechanical positioning, or postural control, in order to maximize energy transfer. Correct postural control requires a strong, stable core. A strong and stable core allows one to transfer energy effectively as well as reduce undue stress. An unstable or weak core, on the other…

  17. Modelling of future hydrogeological conditions at SFR

    Energy Technology Data Exchange (ETDEWEB)

    Holmen, L.G.; Stigsson, M. [Golder Associates, Stockholm (Sweden)

    2001-03-01

    The purpose is to estimate the future groundwater movements at the SFR repository and to produce input to the quantitative safety assessment of the SFR. The future flow pattern of the groundwater is of interest, since components of the waste emplaced in a closed and abandoned repository will dissolve in the groundwater and be transported by the groundwater to the ground surface. The study is based on a system analysis approach. Three-dimensional models were devised of the studied domain. The models include the repository tunnels and the surrounding rock mass with fracture zones. The formal models used for simulation of the groundwater flow are three-dimensional mathematical descriptions of the studied hydraulic system. The studied domain is represented on four scales - regional, local, semi local and detailed - forming four models with different resolutions: regional, local, semi local and detailed models. The local and detailed models include a detailed description of the tunnel system at SFR and of surrounding rock mass and fracture zones. In addition, the detailed model includes description of the different structures that take place inside the deposition tunnels. At the area studied, the shoreline will retreat due to the shore level displacement; this process is included in the models. The studied period starts at 2000 AD and continues until a steady state like situation is reached for the surroundings of the SFR at ca 6000 AD. The models predict that as long as the sea covers the ground above the SFR, the regional groundwater flow as well as the flow in the deposition tunnels are small. However, due to the shore level displacement the shoreline (the sea) will retreat. Because of the retreating shoreline, the general direction of the groundwater flow at SFR will change, from vertical upward to a more horizontal flow; the size of the groundwater flow will be increased as well. The present layout of the SFR includes five deposition tunnels: SILO, BMA, BLA, BTF1

  18. Fabrication of preliminary fuel rods for SFR

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Ki; Oh, Seok Jin; Ko, Young Mo; Woo, Youn Myung; Kim, Ki Hwan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    Metal fuels was selected for fueling many of the first reactors in the US, including the Experimental Breeder Reactor-I (EBR-I) and the Experimental Breeder Reactor-II (EBR-II) in Idaho, the FERMI-I reactor, and the Dounreay Fast Reactor (DFR) in the UK. Metallic U.Pu.Zr alloys were the reference fuel for the US Integral Fast Reactor (IFR) program. Metallic fuel has advantages such as simple fabrication procedures, good neutron economy, high thermal conductivity, excellent compatibility with a Na coolant and inherent passive safety. U-Zr-Pu alloy fuels have been used for SFR (sodium-cooled fast reactor) related to the closed fuel cycle for managing minor actinides and reducing a high radioactivity levels since the 1980s. Fabrication technology of metallic fuel for SFR has been in development in Korea as a national nuclear R and D program since 2007. For the final goal of SFR fuel rod fabrication with good performance, recently, three preliminary fuel rods were fabricated. In this paper, the preliminary fuel rods were fabricated, and then the inspection for QC(quality control) of the fuel rods was performed

  19. Resolution of proliferation issues for a SFR blanket with a specific application

    Energy Technology Data Exchange (ETDEWEB)

    Stauff, N.E. [31 rue baudelaire, voisins le bretonneux, 78960 (France); Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139 (United States); Forget, B.; Driscoll, M.J. [Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139 (United States)

    2009-06-15

    The Sodium Fast Reactor is seen as the most realistic Gen-IV reactor to be built in the near future. France and the US are still developing their designs; these will require improved safety, competitive economics, and also proliferation resistance. To meet this last requirement, both French and American designers show some concerns with the use of breeding blankets. France and the USA won't need breeding blankets to produce plutonium because they already have large amounts of plutonium bred from their LWR fleet to start a new SFR fleet, thus breeding blankets are mainly of interest for minor actinide burning. On the contrary, India and China express great interest in blankets for their SFR designs, to reach a positive breeding gain. For example, the Indian PFBR, a 500 MWe oxide-fueled SFR has a breeding ratio of 1.05. Blankets are used in a Fast Reactor to increase the breeding ratio of the core, by breeding a significant amount of plutonium. The Plutonium bred within these blankets, if these are loaded with Uranium only, is generally of a very high quality, which makes it easily used in a nuclear explosive device. Our research has shown that the plutonium in breeding blankets can be made less attractive to make a nuclear explosive device than LWR-bred plutonium with a burnup of 50 MWd/Kg. Minor actinide doping and moderator addition were the two options studied, as they increase Pu{sup 238} and Pu{sup 240} production. In the work reported here, the methodology developed for securing a breeding blanket was successfully applied to the Indian PFBR. The full paper will describe a design of the PFBR breeding proliferation resistant plutonium within its blankets. The blankets were rendered secure by adding a zirconium hydride moderator and a small volume of MAs. It was demonstrated that reducing the attractiveness of the blanket plutonium would require no external MA dependency by choosing an adequate fuel cycle. The characteristics and performance of this design

  20. Adding calcium improves lithium ferrite core

    Science.gov (United States)

    Lessoff, H.

    1969-01-01

    Adding calcium increases uniformity of grain growth over a wide range of sintering temperatures and reduces porosity within the grain. Ferrite cores containing calcium have square hysteresis loops and high curie temperatures, making them useful in coincident current memories of digital electronic computers.

  1. Fast reactor core concepts to improve transmutation efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Fujimura, Koji; Kawashima, Katsuyuki [Hitachi Research Laboratory, Hitachi, Ltd., 7-1-1, Omika-cho, Hitachi-shi, Ibaraki, 319-1221 Japan (Japan); Itooka, Satoshi [Hitachi-GE Nuclear Energy, Ltd., 3-1-1, Saiwai-cho, Hitachi-shi, Ibaraki, 317-0073 Japan (Japan)

    2015-12-31

    Fast Reactor (FR) core concepts to improve transmutation efficiency were conducted. A heterogeneous MA loaded core was designed based on the 1000MWe-ABR breakeven core. The heterogeneous MA loaded core with Zr-H loaded moderated targets had a better transmutation performance than the MA homogeneous loaded core. The annular pellet rod design was proposed as one of the possible design options for the MA target. It was shown that using annular pellet MA rods mitigates the self-shielding effect in the moderated target so as to enhance the transmutation rate.

  2. On the [CII]-SFR relation in high redshift galaxies

    CERN Document Server

    Vallini, L; Ferrara, A; Pallottini, A; Yue, B

    2015-01-01

    After two ALMA observing cycles, only a handful of [CII] $158\\,\\mu m$ emission line searches in z>6 galaxies have reported a positive detection, questioning the applicability of the local [CII]-SFR relation to high-z systems. To investigate this issue we use the Vallini et al. 2013 (V13) model, based on high-resolution, radiative transfer cosmological simulations to predict the [CII] emission from the interstellar medium of a z~7 (halo mass $M_h=1.17\\times10^{11}M_{\\odot}$) galaxy. We improve the V13 model by including (a) a physically-motivated metallicity (Z) distribution of the gas, (b) the contribution of Photo-Dissociation Regions (PDRs), (c) the effects of Cosmic Microwave Background on the [CII] line luminosity. We study the relative contribution of diffuse neutral gas to the total [CII] emission ($F _{diff}/F_{tot}$) for different SFR and Z values. We find that the [CII] emission arises predominantly from PDRs: regardless of the galaxy properties, $F _{diff}/F_{tot}\\leq 10$% since, at these early epoc...

  3. Rotary Mode Core Sample System availability improvement

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, W.W.; Bennett, K.L.; Potter, J.D. [Westinghouse Hanford Co., Richland, WA (United States); Cross, B.T.; Burkes, J.M.; Rogers, A.C. [Southwest Research Institute (United States)

    1995-02-28

    The Rotary Mode Core Sample System (RMCSS) is used to obtain stratified samples of the waste deposits in single-shell and double-shell waste tanks at the Hanford Site. The samples are used to characterize the waste in support of ongoing and future waste remediation efforts. Four sampling trucks have been developed to obtain these samples. Truck I was the first in operation and is currently being used to obtain samples where the push mode is appropriate (i.e., no rotation of drill). Truck 2 is similar to truck 1, except for added safety features, and is in operation to obtain samples using either a push mode or rotary drill mode. Trucks 3 and 4 are now being fabricated to be essentially identical to truck 2.

  4. Improvement of core degradation model in ISAAC

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Ha; Kim, See Darl; Park, Soo Yong

    2004-02-01

    If water inventory in the fuel channels depletes and fuel rods are exposed to steam after uncover in the pressure tube, the decay heat generated from fuel rods is transferred to the pressure tube and to the calandria tube by radiation, and finally to the moderator in the calandria tank by conduction. During this process, the cladding will be heated first and ballooned when the fuel gap internal pressure exceeds the primary system pressure. The pressure tube will be also ballooned and will touch the calandria tube, increasing heat transfer rate to the moderator. Although these situation is not desirable, the fuel channel is expected to maintain its integrity as long as the calandria tube is submerged in the moderator, because the decay heat could be removed to the moderator through radiation and conduction. Therefore, loss of coolant and moderator inside and outside the channel may cause severe core damage including horizontal fuel channel sagging and finally loss of channel integrity. The sagged channels contact with the channels located below and lose their heat transfer area to the moderator. As the accident goes further, the disintegrated fuel channels will be heated up and relocated onto the bottom of the calandria tank. If the temperature of these relocated materials is high enough to attack the calandria tank, the calandria tank would fail and molten material would contact with the calandria vault water. Steam explosion and/or rapid steam generation from this interaction may threaten containment integrity. Though a detailed model is required to simulate the severe accident at CANDU plants, complexity of phenomena itself and inner structures as well as lack of experimental data forces to choose a simple but reasonable model as the first step. ISAAC 1.0 was developed to model the basic physicochemical phenomena during the severe accident progression. At present, ISAAC 2.0 is being developed for accident management guide development and strategy evaluation. In

  5. Improving Engine Efficiency Through Core Developments

    Science.gov (United States)

    Heidmann, James D.

    2011-01-01

    The NASA Environmentally Responsible Aviation (ERA) Project and Fundamental Aeronautics Projects are supporting compressor and turbine research with the goal of reducing aircraft engine fuel burn and greenhouse gas emissions. The primary goals of this work are to increase aircraft propulsion system fuel efficiency for a given mission by increasing the overall pressure ratio (OPR) of the engine while maintaining or improving aerodynamic efficiency of these components. An additional area of work involves reducing the amount of cooling air required to cool the turbine blades while increasing the turbine inlet temperature. This is complicated by the fact that the cooling air is becoming hotter due to the increases in OPR. Various methods are being investigated to achieve these goals, ranging from improved compressor three-dimensional blade designs to improved turbine cooling hole shapes and methods. Finally, a complementary effort in improving the accuracy, range, and speed of computational fluid mechanics (CFD) methods is proceeding to better capture the physical mechanisms underlying all these problems, for the purpose of improving understanding and future designs.

  6. Casting Technology Development for SFR Metallic Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.T.; Oh, S.J.; Ryu, H.J.; Kim, K.H.; Lee, Y.S.; Kim, S.K.; Woo, Y.M.; Ko, Y.M.; Lee, C.B. [KAERI, 150 Deokjin-dong, Yuseong, Daejeon, 305-353 (Korea, Republic of)

    2009-06-15

    Fabrication technology of metallic fuel for sodium fast reactor (SFR) is being developed in Korea as a national mid- and long-term nuclear R and D program from 2007. The metallic fuel for SFR should be remotely fabricated under a radiation shielded environment such as a glove box or hot cell, because it contains long-lived minor actinides such as Np, Am and Cm. In order to design a reliable remote fabrication system, various casting techniques have been studied by using U-Zr and U-Zr-RE alloys as surrogate fuel material. Rare earth elements such as Ce or Nd were used as a surrogate for minor actinide elements or solid solution fission products. Macro-scale soundness, microstructures and compositional homogeneity of metallic fuel samples fabricated by vacuum-assisted injection casting, vacuum-assisted gravity casting, centrifugal atomization and continuous casting were compared. Although sound slugs of U-Zr metallic fuel of 4{approx}6 mm in diameter could be fabricated by vacuum-assisted injection casting or vacuum-assisted gravity casting, it was necessary to consider that vaporization of Am and volume of radioactive wastes such as crucibles and molds should be minimized. Effects of casting parameters on the volatile loss, and effects of coatings on the chemical reaction between metallic fuel and molds are discussed. Some methods to reduce the volatile Am loss and waste molds and crucibles will be proposed. Short rods of U-Zr or U-Zr-Ce fuel will be fabricated by the vacuum-assisted gravity casting technique for an irradiation test in the HANARO research reactor from 2010. (authors)

  7. Project SAFE. Complexing agents in SFR

    Energy Technology Data Exchange (ETDEWEB)

    Fanger, G.; Skagius, K.; Wiborgh, M. [Kemakta Konsult AB, Stockholm (Sweden)

    2001-01-01

    Low- and intermediate level radioactive waste, produced at Swedish nuclear power plants, will be deposited in an underground repository, SFR. Different substances in the waste or in degradation products emanating from the waste, and chemicals added during the building of cementitious barriers in the repository, may exhibit complexing properties. The complexation of radionuclides with such ligands may increase the mobility of the deposited radionuclides as sorption on the cement phases is decreased and solubility increased. This could lead to an increased leaching of the radionuclides from the repository to the geosphere and biosphere. To be able to evaluate the implications for the function and long-term safety of the repository a study has been performed on complexants in SFR. The study is a part of project SAFE (Safety Assessment of Final Repository for operational Radioactive Waste) at the Swedish Nuclear Fuel and Waste Management Co, SKB. Concentrations of complexants were calculated in different waste types in the repository and compared to critical levels above which radionuclide sorption may be affected. The analysis is based on recent research presented in international and national literature sources. The waste in SFR that may act or give rise to substances with complexing properties mainly consists of cellulose materials, including cement additives used in waste conditioning and backfill grout. The radioactive waste also contains chemicals mainly used in decontamination processes at the nuclear power plants, e.g. EDTA, NTA, gluconate, citric acid and oxalic acid. The calculations performed in this report show that the presence of complexants in SFR may lead to a sorption reduction for some radionuclides in certain waste types. This may have to be considered when performing calculations of the radionuclide transport. Concentration calculations of isosaccharinic acid (ISA), using a degradation yield of 0.1 mole/kg cellulose (2%), showed that the limit above

  8. Improved Parallel Apriori Algorithm for Multi-cores

    Directory of Open Access Journals (Sweden)

    Swati Rustogi

    2017-04-01

    Full Text Available Apriori algorithm is one of the most popular data mining techniques, which is used for mining hidden relationship in large data. With parallelism, a large data set can be mined in less amount of time. Apart from the costly distributed systems, a computer supporting multi core environment can be used for applying parallelism. In this paper an improved Apriori algorithm for multi-core environment is proposed. The main contributions of this paper are:  An efficient Apriori algorithm that applies data parallelism in multi-core environment by reducing the time taken to count the frequency of candidate item sets.  The performance of proposed algorithm is evaluated for multiple cores on basis of speedup.  The performance of the proposed algorithm is compared with the other such parallel algorithm and it shows an improvement by more than 15% preliminary experiment

  9. Development of Melting Crucible Materials of Metallic Fuel Slug for SFR

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K. H.; Lee, C. T.; Oh, S. J.; Kim, S. K.; Lee, C. B.; Ko, Y. M.; Woo, W. M

    2010-01-15

    The fabrication process of metallic fuel for SFR(sodium fast reactor) of Generation-IV candidate reactors is composed of the fabrication of fuel pin, fuel rod, and fuel assembly. The key technology of the fabrication process for SFR can be referred to the fabrication technology of fuel pin. As SFR fuel contains MA(minor actinide) elements proceeding the recycling of actinide elements, it is so important to extinguish MA during irradiation in SFR, included in nuclear fuel through collection of volatile MA elements during fabrication of fuel pin. Hence, it is an imminent circumstance to develop the fabrication process of fuel pin. This report is an state-of art report related to the characteristics of irradiation performance for U-Zr-Pu metallic fuel, and the apparatus and the technology of conventional injection casting process. In addition, to overcome the drawbacks of the conventional injection casting and the U-Zr-Pu fuel, new fabrication technologies such as the gravity casting process, the casting of fuel pin to metal-barrier mold, the fabrication of particulate metallic fuel utilizing centrifugal atomization is surveyed and summarized. The development of new U-10Mo-X metallic fuel as nuclear fuel having a single phase in the temperature range between 550 and 950 .deg. C, reducing the re-distribution of the fuel elements and improving the compatibility between fuel and cladding, is also surveyed and summarized.

  10. Project SAFE. Complexing agents in SFR

    Energy Technology Data Exchange (ETDEWEB)

    Fanger, G.; Skagius, K.; Wiborgh, M. [Kemakta Konsult AB, Stockholm (Sweden)

    2001-01-01

    Low- and intermediate level radioactive waste, produced at Swedish nuclear power plants, will be deposited in an underground repository, SFR. Different substances in the waste or in degradation products emanating from the waste, and chemicals added during the building of cementitious barriers in the repository, may exhibit complexing properties. The complexation of radionuclides with such ligands may increase the mobility of the deposited radionuclides as sorption on the cement phases is decreased and solubility increased. This could lead to an increased leaching of the radionuclides from the repository to the geosphere and biosphere. To be able to evaluate the implications for the function and long-term safety of the repository a study has been performed on complexants in SFR. The study is a part of project SAFE (Safety Assessment of Final Repository for operational Radioactive Waste) at the Swedish Nuclear Fuel and Waste Management Co, SKB. Concentrations of complexants were calculated in different waste types in the repository and compared to critical levels above which radionuclide sorption may be affected. The analysis is based on recent research presented in international and national literature sources. The waste in SFR that may act or give rise to substances with complexing properties mainly consists of cellulose materials, including cement additives used in waste conditioning and backfill grout. The radioactive waste also contains chemicals mainly used in decontamination processes at the nuclear power plants, e.g. EDTA, NTA, gluconate, citric acid and oxalic acid. The calculations performed in this report show that the presence of complexants in SFR may lead to a sorption reduction for some radionuclides in certain waste types. This may have to be considered when performing calculations of the radionuclide transport. Concentration calculations of isosaccharinic acid (ISA), using a degradation yield of 0.1 mole/kg cellulose (2%), showed that the limit above

  11. Review of SFR In-Vessel HCDA Source Terms

    Energy Technology Data Exchange (ETDEWEB)

    Suk, S. D.; Ha, K. S. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-10-15

    An effort has been made in this study to search for and review the literatures on the studies of the phenomena related to the release of radionuclides and aerosols to the reactor containment of the sodium fast reactor (SFR) plants ( i.e., in-vessel source term. Review work is focused on the experimental programs to investigate the phenomena related to determining the source terms, with a brief review on supporting analytical models and computer programs. As a result of the severe accidents experienced at TMI and Chernobyl, much work has been done on the energetic CDA bubble source term (also called 'primary' or 'instantaneous' source term) defined as the amount of radioactive material released from the reactor vessel to the containment due to the rapid expansion of fuel or sodium leading to a failure of the vessel head. In this study, the research programs conducted to investigate the CDA (core disruptive accident) bubble behavior in the sodium pool for determining 'primary' or 'instantaneous' source term are introduced. The research programs to investigate the release and transport of fission products(FPs) and aerosols in the reactor containment (i.e., in-containment source term) are not described in this study.

  12. Thermal hydraulic analysis of the JMTR improved LEU-core

    Energy Technology Data Exchange (ETDEWEB)

    Tabata, Toshio; Nagao, Yoshiharu; Komukai, Bunsaku; Naka, Michihiro; Fujiki, Kazuo [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Takeda, Takashi [Radioactive Waste Management and Nuclear Facility Decommissioning Technology Center, Tokai, Ibaraki (Japan)

    2003-01-01

    After the investigation of the new core arrangement for the JMTR reactor in order to enhance the fuel burn-up and consequently extend the operation period, the ''improved LEU core'' that utilized 2 additional fuel elements instead of formerly installed reflector elements, was adopted. This report describes the results of the thermal-hydraulic analysis of the improved LEU core as a part of safety analysis for the licensing. The analysis covers steady state, abnormal operational transients and accidents, which were described in the annexes of the licensing documents as design bases events. Calculation conditions for the computer codes were conservatively determined based on the neutronic analysis results and others. The results of the analysis, that revealed the safety criteria were satisfied on the fuel temperature, DNBR and primary coolant temperature, were used in the licensing. The operation license of the JMTR with the improved LEU core was granted in March 2001, and the reactor operation with new core started in November 2001 as 142nd operation cycle. (author)

  13. The terrestrial biosphere in the SFR region

    Energy Technology Data Exchange (ETDEWEB)

    Jerling, L.; Isaeus, M. [Stockholm Univ. (Sweden). Dept. of Botany; Lanneck, J. [Stockholm Univ. (Sweden). Dept. of Physical Geography; Lindborg, T.; Schueldt, R. [Danish Nature Council, Copenhagen (Denmark)

    2001-03-01

    This report is a part of the SKB project 'SAFE' (Safety Assessment of the Final Repository of Radioactive Operational Waste). The aim of project SAFE is to update the previous safety analysis of SFR-1.SFR-1 is a facility for disposal of low and intermediate level radioactive waste, which is situated in bedrock beneath the Baltic Sea, one km off the coast near the Forsmark nuclear power plant in Northern Uppland. A part of the SAFE-analysis aims at analysing the transport of radionuclides in the ecosystems.To do so one has to build a model that includes a large amount of information concerning the biosphere.The first step is to collect and compile descriptions of the biosphere.This report is a first attempt to characterise the terrestrial environment of the SFR area of Forsmark. In the first part of the report the terrestrial environment, land class distribution and production of the area is described. The primary production in different terrestrial ecosystems is estimated for a model area in the Forsmark region. The estimations are based on the actual land class distribution and the values for the total primary production (d.w. above ground biomass)and the amount carbon produced, presented as g/m{sup 2} for each land class respectively. An important aspect of the biosphere is the vegetation and its development. The future development of vegetation is of interest since production,decomposition and thus storage of organic material, vary strongly among vegetation types and this has strong implications for the transport of radionuclides.Therefore an attempt to describe the development of terrestrial vegetation has been made in the second part. Any prediction of future vegetation is based on knowledge of the past together with premises for the future development.The predictions made, thus, becomes marred with errors enforced by the assumptions and incomplete information of the past. The assumptions made for the predictions in this report are crude and results

  14. The terrestrial biosphere in the SFR region

    Energy Technology Data Exchange (ETDEWEB)

    Jerling, L.; Isaeus, M. [Stockholm Univ. (Sweden). Dept. of Botany; Lanneck, J. [Stockholm Univ. (Sweden). Dept. of Physical Geography; Lindborg, T.; Schueldt, R. [Danish Nature Council, Copenhagen (Denmark)

    2001-03-01

    This report is a part of the SKB project 'SAFE' (Safety Assessment of the Final Repository of Radioactive Operational Waste). The aim of project SAFE is to update the previous safety analysis of SFR-1.SFR-1 is a facility for disposal of low and intermediate level radioactive waste, which is situated in bedrock beneath the Baltic Sea, one km off the coast near the Forsmark nuclear power plant in Northern Uppland. A part of the SAFE-analysis aims at analysing the transport of radionuclides in the ecosystems.To do so one has to build a model that includes a large amount of information concerning the biosphere.The first step is to collect and compile descriptions of the biosphere.This report is a first attempt to characterise the terrestrial environment of the SFR area of Forsmark. In the first part of the report the terrestrial environment, land class distribution and production of the area is described. The primary production in different terrestrial ecosystems is estimated for a model area in the Forsmark region. The estimations are based on the actual land class distribution and the values for the total primary production (d.w. above ground biomass)and the amount carbon produced, presented as g/m{sup 2} for each land class respectively. An important aspect of the biosphere is the vegetation and its development. The future development of vegetation is of interest since production,decomposition and thus storage of organic material, vary strongly among vegetation types and this has strong implications for the transport of radionuclides.Therefore an attempt to describe the development of terrestrial vegetation has been made in the second part. Any prediction of future vegetation is based on knowledge of the past together with premises for the future development.The predictions made, thus, becomes marred with errors enforced by the assumptions and incomplete information of the past. The assumptions made for the predictions in this report are crude and results

  15. Mechanical modelling of transient- to- failure SFR fuel cladding

    Energy Technology Data Exchange (ETDEWEB)

    Feria, F.; Herranz, L. E.

    2014-07-01

    The response of Sodium Fast Reactor (SFR) fuel rods to transient accident conditions is an important safety concern. During transients the cladding strain caused by the stress due to pellet cladding mechanical interaction (PCMI) can lead to failure. Due to the fact that SFR fuel rods are commonly clad with strengthened material made of stainless steel (SS), cladding is usually treated as an elastic-perfectly-plastic material. However, viscoplastic behaviour can contribute to mechanical strain at high temperature (> 1000 K). (Author)

  16. Site investigation SFR. Water-rock interaction and mixing modelling in the SFR

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-10-15

    During 2008, the Swedish Nuclear Fuel and Waste Management Company (SKB) initiated an investigation programme for a future expansion of the final repository for low and medium level radioactive operational waste, SFR, located about 150 km north of Stockholm. The purpose of the investigations was to define and characterise a bedrock volume large enough to allow further storage of operational waste from existing Swedish nuclear power plants and future waste from the decommissioning and dismantling of nuclear power plant reactors (SKB 2008). Of several alternatives, a selected location was investigated southwest of the present SFR tunnel system. As part of the SFR Site Descriptive Model, the objective of the hydrogeochemical site description is to describe the chemistry, origin and distribution of groundwaters in the bedrock and the hydrogeochemical processes involved in their evolution. Hydrogeochemical information (salinity distribution, groundwater residence time, palaeohydrogeochemical input, etc.) are also of importance to help constrain the hydrogeological descriptive model. The hydrogeochemical modelling work has been performed in three steps, resulting in three model versions (0.1, 0.2 and 1.0). In versions 0.1 and 0.2, explorative analyses using traditional geochemical approaches (trend plots, x-y scatter plots, 3D visualisations, etc.) were performed to describe the data and to provide an early insight and understanding of the site. The final hydrogeochemical site description version 1.0 (Nilsson et al. 2011) includes data from the previous versions, as well as subsequent complementary data from the SFR extension project, and all these data are further evaluated using additional modelling approaches and techniques. In this context, the present report gives a more detailed analysis of the available data for some hydrogeochemical systems and a detailed description of the results of the geochemical and statistical modelling. One of the main aims is to establish

  17. Weld Joint Design for SFR Metallic Fuel Element Closures

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jung Won; Kim, Soo Sung; Woo, Yoon Myeng; Kim, Hyung Tae; Kim, Ki Hwan; Yoon, Kyung Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The sodium-cooled fast reactor (SFR) system is among the six systems selected for Gen-IV promising systems and expected to become available for commercial introduction around 2030. In Korea, the R and D on SFR has been begun since 1997, as one of the national long-term nuclear R and D programs. The international collaborative research is under way on fuel developments within Advanced Fuel Project for Gen-IV SFR with the closed fuel cycle of full actinide recycling, while TRU bearing metallic fuel, U-TRU-Zr alloy fuel, was selected and is being developed. For the fabrication of SFR metallic fuel elements, the endplug welding is a crucial process. The sealing of endplug to cladding tube should be hermetically perfect to prevent a leakage of fission gases and to maintain a good reactor performance. In this study, the joint designs for endplug welding were investigated. For the irradiation test of SFR metallic fuel element, the TIG welding technique was adopted and the welding joint design was developed based on the welding conditions and parameters established. In order to make SFR metallic fuel elements, the weld joint design was developed based on the TIG welding technique.

  18. Feasibility Study on the Sodium Compatibility Test for Fuel Cladding of SFR

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jun Hwan; Shin, Sang Hun; Park, Sang Gyu; Ryu, Woo Seog; Kim, Sung Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    A Sodium-cooled Fast Reactor (SFR), a reactor that uses fast neutrons as a fission process, is considered one of the most probable candidates in next-generation reactors because it can maximize the uranium utilization when compared to conventional water reactor. Liquid sodium is used as a coolant in a SFR, because it has superior efficiency of fast neutron economy and high thermal conductivity, which enables a high power core design. However, previous research reported that fuel cladding materials like austenitic and ferritic-martensitic steel (FMS) react sodium coolant so that it results in the loss of the thickness, intergranular attack, and carburization or decarburization process to induce the change of the mechanical property. Fuel cladding, a seamless tube which has approximately 0.5mm in thickness and 3m in length is the component which covers fuel to protect radioactive species from being released. Because of its smaller thickness, the mechanical properties of the cladding are easily affected by the small changes of material property. This paper summarizes the status of sodium-material compatibility facility and proposes the optimal option in the case of the SFR fuel cladding. Previous researches revealed that assessing in-situ mechanical property is important in the case of cladding material owing to its dimensional characteristic. Optimal test method for assessing sodium compatibility of the cladding tube can be proposed that pressurized creep test under the controlled liquid sodium environment.

  19. Safety analysis SFR 1. Long-term safety

    Energy Technology Data Exchange (ETDEWEB)

    2008-12-15

    An updated assessment of the long-term safety of SKB's final repository for radioactive operational waste, SFR 1, is presented in this report. The report is included in the safety analysis report for SFR 1. The most recent account of long-term safety was submitted to the regulatory authorities in 2001. The present report has been compiled on SKB's initiative to address the regulatory authorities' viewpoints regarding the preceding account of long-term safety. Besides the new mode of working with safety functions there is another important difference between the 2001 safety assessment and the current assessment: The time horizon in the current assessment has been extended to 100,000 years in order to include the effect of future climate changes. The purpose of this renewed assessment of the long-term safety of SFR 1 is to show with improved data that the repository is capable of protecting human health and the environment against ionizing radiation in a long-term perspective. This is done by showing that calculated risks lie below the risk criteria stipulated by the regulatory authorities. SFR 1 is built to receive, and after closure serve as a passive repository for, low. and intermediate-level radioactive waste. The disposal chambers are situated in rock beneath the sea floor, covered by about 60 metres of rock. The underground part of the facility is reached via two tunnels whose entrances are near the harbour. The repository has been designed so that it can be abandoned after closure without further measures needing to be taken to maintain its function. The waste in SFR 1 is short-lived low- and intermediate-level waste. After 100 years the activity is less than half, and after 1,000 years only about 2% of the original activity remains. The report on long-term safety comprises eleven chapters. Chapter 1 Introduction. The chapter describes the purpose, background, format and contents of SAR-08, applicable regulations and injunctions, and the

  20. Safety analysis SFR 1. Long-term safety

    Energy Technology Data Exchange (ETDEWEB)

    2008-12-15

    An updated assessment of the long-term safety of SKB's final repository for radioactive operational waste, SFR 1, is presented in this report. The report is included in the safety analysis report for SFR 1. The most recent account of long-term safety was submitted to the regulatory authorities in 2001. The present report has been compiled on SKB's initiative to address the regulatory authorities' viewpoints regarding the preceding account of long-term safety. Besides the new mode of working with safety functions there is another important difference between the 2001 safety assessment and the current assessment: The time horizon in the current assessment has been extended to 100,000 years in order to include the effect of future climate changes. The purpose of this renewed assessment of the long-term safety of SFR 1 is to show with improved data that the repository is capable of protecting human health and the environment against ionizing radiation in a long-term perspective. This is done by showing that calculated risks lie below the risk criteria stipulated by the regulatory authorities. SFR 1 is built to receive, and after closure serve as a passive repository for, low. and intermediate-level radioactive waste. The disposal chambers are situated in rock beneath the sea floor, covered by about 60 metres of rock. The underground part of the facility is reached via two tunnels whose entrances are near the harbour. The repository has been designed so that it can be abandoned after closure without further measures needing to be taken to maintain its function. The waste in SFR 1 is short-lived low- and intermediate-level waste. After 100 years the activity is less than half, and after 1,000 years only about 2% of the original activity remains. The report on long-term safety comprises eleven chapters. Chapter 1 Introduction. The chapter describes the purpose, background, format and contents of SAR-08, applicable regulations and injunctions, and the

  1. Swi5-Sfr1 protein stimulates Rad51-mediated DNA strand exchange reaction through organization of DNA bases in the presynaptic filament.

    KAUST Repository

    Fornander, Louise H

    2013-12-03

    The Swi5-Sfr1 heterodimer protein stimulates the Rad51-promoted DNA strand exchange reaction, a crucial step in homologous recombination. To clarify how this accessory protein acts on the strand exchange reaction, we have analyzed how the structure of the primary reaction intermediate, the Rad51/single-stranded DNA (ssDNA) complex filament formed in the presence of ATP, is affected by Swi5-Sfr1. Using flow linear dichroism spectroscopy, we observe that the nucleobases of the ssDNA are more perpendicularly aligned to the filament axis in the presence of Swi5-Sfr1, whereas the bases are more randomly oriented in the absence of Swi5-Sfr1. When using a modified version of the natural protein where the N-terminal part of Sfr1 is deleted, which has no affinity for DNA but maintained ability to stimulate the strand exchange reaction, we still observe the improved perpendicular DNA base orientation. This indicates that Swi5-Sfr1 exerts its activating effect through interaction with the Rad51 filament mainly and not with the DNA. We propose that the role of a coplanar alignment of nucleobases induced by Swi5-Sfr1 in the presynaptic Rad51/ssDNA complex is to facilitate the critical matching with an invading double-stranded DNA, hence stimulating the strand exchange reaction.

  2. Site investigation SFR. Water-rock interaction and mixing modelling in the SFR

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-10-15

    During 2008, the Swedish Nuclear Fuel and Waste Management Company (SKB) initiated an investigation programme for a future expansion of the final repository for low and medium level radioactive operational waste, SFR, located about 150 km north of Stockholm. The purpose of the investigations was to define and characterise a bedrock volume large enough to allow further storage of operational waste from existing Swedish nuclear power plants and future waste from the decommissioning and dismantling of nuclear power plant reactors (SKB 2008). Of several alternatives, a selected location was investigated southwest of the present SFR tunnel system. As part of the SFR Site Descriptive Model, the objective of the hydrogeochemical site description is to describe the chemistry, origin and distribution of groundwaters in the bedrock and the hydrogeochemical processes involved in their evolution. Hydrogeochemical information (salinity distribution, groundwater residence time, palaeohydrogeochemical input, etc.) are also of importance to help constrain the hydrogeological descriptive model. The hydrogeochemical modelling work has been performed in three steps, resulting in three model versions (0.1, 0.2 and 1.0). In versions 0.1 and 0.2, explorative analyses using traditional geochemical approaches (trend plots, x-y scatter plots, 3D visualisations, etc.) were performed to describe the data and to provide an early insight and understanding of the site. The final hydrogeochemical site description version 1.0 (Nilsson et al. 2011) includes data from the previous versions, as well as subsequent complementary data from the SFR extension project, and all these data are further evaluated using additional modelling approaches and techniques. In this context, the present report gives a more detailed analysis of the available data for some hydrogeochemical systems and a detailed description of the results of the geochemical and statistical modelling. One of the main aims is to establish

  3. Sand Production during Improved Oil Recovery in Unconsolidated Cores

    OpenAIRE

    Mohammad A. J. Ali.; S. M. Kholosy; A. A. Al-Haddad; K. K. AL-Hamad

    2012-01-01

    Steam injection is a mechanisms used for improved oil recovery (IOR) in heavy oil reservoirs. Heating the reservoir reduces the oil viscosity and causes the velocity of the moving oil to increase; and thus, the heated zone around the injection well will have high velocity. The increase of velocity in an unconsolidated formation is usually accompanied with sand movement in the reservoir creating a potential problem. Core samples from different wells in Kuwait were used to examine sand producti...

  4. How Universal is the SFR - H2 Relation?

    CERN Document Server

    Feldmann, R; Kravtsov, A V

    2010-01-01

    It is a well established empirical fact that the surface density of the star formation rate, Sigma_SFR, strongly correlates with the surface density of molecular hydrogen, Sigma_H2, at least when averaged over large (~kpc) scales. Much less is known, however, if (and how) the Sigma_SFR-Sigma_H2 relation depends on environmental parameters, such as the metallicity or the UV radiation field in the interstellar medium (ISM). Furthermore, observations indicate that the scatter in the Sigma_SFR-Sigma_H2 relation increases rapidly with decreasing averaging scale. How the scale dependent scatter is generated and how one recovers a tight ~ kpc scale Sigma_SFR-Sigma_H2 relation in the first place is still largely debated. Here, we explore these questions with hydrodynamical simulations that follow the formation and destruction of H2, include radiative transfer of UV radiation, and resolve the ISM on ~60 pc scales. We find that within the considered range of H2 surface densities (10-100 Msun/pc^2) the Sigma_SFR-Sigma_H...

  5. Ketogenic diet improves core symptoms of autism in BTBR mice.

    Science.gov (United States)

    Ruskin, David N; Svedova, Julia; Cote, Jessica L; Sandau, Ursula; Rho, Jong M; Kawamura, Masahito; Boison, Detlev; Masino, Susan A

    2013-01-01

    Autism spectrum disorders share three core symptoms: impaired sociability, repetitive behaviors and communication deficits. Incidence is rising, and current treatments are inadequate. Seizures are a common comorbidity, and since the 1920's a high-fat, low-carbohydrate ketogenic diet has been used to treat epilepsy. Evidence suggests the ketogenic diet and analogous metabolic approaches may benefit diverse neurological disorders. Here we show that a ketogenic diet improves autistic behaviors in the BTBR mouse. Juvenile BTBR mice were fed standard or ketogenic diet for three weeks and tested for sociability, self-directed repetitive behavior, and communication. In separate experiments, spontaneous intrahippocampal EEGs and tests of seizure susceptibility (6 Hz corneal stimulation, flurothyl, SKF83822, pentylenetetrazole) were compared between BTBR and control (C57Bl/6) mice. Ketogenic diet-fed BTBR mice showed increased sociability in a three-chamber test, decreased self-directed repetitive behavior, and improved social communication of a food preference. Although seizures are a common comorbidity with autism, BTBR mice fed a standard diet exhibit neither spontaneous seizures nor abnormal EEG, and have increased seizure susceptibility in just one of four tests. Thus, behavioral improvements are dissociable from any antiseizure effect. Our results suggest that a ketogenic diet improves multiple autistic behaviors in the BTBR mouse model. Therefore, ketogenic diets or analogous metabolic strategies may offer novel opportunities to improve core behavioral symptoms of autism spectrum disorders.

  6. Ketogenic diet improves core symptoms of autism in BTBR mice.

    Directory of Open Access Journals (Sweden)

    David N Ruskin

    Full Text Available Autism spectrum disorders share three core symptoms: impaired sociability, repetitive behaviors and communication deficits. Incidence is rising, and current treatments are inadequate. Seizures are a common comorbidity, and since the 1920's a high-fat, low-carbohydrate ketogenic diet has been used to treat epilepsy. Evidence suggests the ketogenic diet and analogous metabolic approaches may benefit diverse neurological disorders. Here we show that a ketogenic diet improves autistic behaviors in the BTBR mouse. Juvenile BTBR mice were fed standard or ketogenic diet for three weeks and tested for sociability, self-directed repetitive behavior, and communication. In separate experiments, spontaneous intrahippocampal EEGs and tests of seizure susceptibility (6 Hz corneal stimulation, flurothyl, SKF83822, pentylenetetrazole were compared between BTBR and control (C57Bl/6 mice. Ketogenic diet-fed BTBR mice showed increased sociability in a three-chamber test, decreased self-directed repetitive behavior, and improved social communication of a food preference. Although seizures are a common comorbidity with autism, BTBR mice fed a standard diet exhibit neither spontaneous seizures nor abnormal EEG, and have increased seizure susceptibility in just one of four tests. Thus, behavioral improvements are dissociable from any antiseizure effect. Our results suggest that a ketogenic diet improves multiple autistic behaviors in the BTBR mouse model. Therefore, ketogenic diets or analogous metabolic strategies may offer novel opportunities to improve core behavioral symptoms of autism spectrum disorders.

  7. SFR Site Investigation. Evaluation of selected interference tests and pressure responses during drilling at SFR

    Energy Technology Data Exchange (ETDEWEB)

    Walger, Ellen; Ludvigson, Jan-Erik; Gentzschein, Bengt (Geosigma AB (Sweden))

    2010-10-15

    In this activity, evaluation of selected hydraulic interference tests and drilling activities within the SFR area performed during 2008-2010 has been made. During the selected interference tests, pumping (or injection) was carried out in boreholes KFR105, HFR101 (both pumping and injection) and HFR102 during the time period from May, 2008 to March, 2010. Groundwater head measurements were performed in all existing SFR-boreholes at the time of testing during the entire test periods as well as during different drilling periods of boreholes HFR102, KFR27, KFR102A, KFR105, HFR106 and KFR106. The activity involves identification and evaluation of potential pressure responses in all instrumented SFR-boreholes from three interference tests and drilling of six boreholes. A fourth interference test (in HFR102), for which no responses were detected by the preliminary analysis, was also included for more detailed evaluation. For the four interference test, quantitative evaluation of hydraulic parameters and response indices of the responding observation sections was made when possible. Finally, a resulting response matrix was prepared for the interference tests. The drilling responses were classified by diagnostic analysis and response index 1, which is based on the response time lag. The hydraulic diffusivity T/S of the responding observation sections was estimated from the response time lags during drilling. For the drilling responses, a response matrix based on the diagnostic analysis and probable depth of response was prepared as well as a resulting response matrix based on response index 1. The pressure responses in the observation boreholes during the interference tests in KFR105 and HFR101 were generally rather slow and weak and in many cases significantly delayed, both at start and stop of pumping/injection respectively. According to the response analysis, the most distinct and fastest responses were found in borehole sections KFR104:1-2 during the interference

  8. SFR Site Investigation. Evaluation of selected interference tests and pressure responses during drilling at SFR

    Energy Technology Data Exchange (ETDEWEB)

    Walger, Ellen; Ludvigson, Jan-Erik; Gentzschein, Bengt (Geosigma AB (Sweden))

    2010-10-15

    In this activity, evaluation of selected hydraulic interference tests and drilling activities within the SFR area performed during 2008-2010 has been made. During the selected interference tests, pumping (or injection) was carried out in boreholes KFR105, HFR101 (both pumping and injection) and HFR102 during the time period from May, 2008 to March, 2010. Groundwater head measurements were performed in all existing SFR-boreholes at the time of testing during the entire test periods as well as during different drilling periods of boreholes HFR102, KFR27, KFR102A, KFR105, HFR106 and KFR106. The activity involves identification and evaluation of potential pressure responses in all instrumented SFR-boreholes from three interference tests and drilling of six boreholes. A fourth interference test (in HFR102), for which no responses were detected by the preliminary analysis, was also included for more detailed evaluation. For the four interference test, quantitative evaluation of hydraulic parameters and response indices of the responding observation sections was made when possible. Finally, a resulting response matrix was prepared for the interference tests. The drilling responses were classified by diagnostic analysis and response index 1, which is based on the response time lag. The hydraulic diffusivity T/S of the responding observation sections was estimated from the response time lags during drilling. For the drilling responses, a response matrix based on the diagnostic analysis and probable depth of response was prepared as well as a resulting response matrix based on response index 1. The pressure responses in the observation boreholes during the interference tests in KFR105 and HFR101 were generally rather slow and weak and in many cases significantly delayed, both at start and stop of pumping/injection respectively. According to the response analysis, the most distinct and fastest responses were found in borehole sections KFR104:1-2 during the interference

  9. Project SAFE. Update of the SFR-1 safety assessment. Phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Johan [ed.] [Golder Associates AB (Sweden); Riggare, P. [ed.] [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Skagius, K. [ed.] [Kemakta Konsult AB, Stockholm (Sweden)

    1998-10-01

    SFR-1 is a facility for disposal of low-level radioactive operational waste from the nuclear power plants in Sweden. Low-level radioactive waste from industry, medicine, and research is also disposed in SFR-1. The facility is situated in bedrock beneath the Baltic Sea, 1 km off the coast near the Forsmark nuclear power plant. SFR-1 was built between the years 1983 and 1988. An assessment of the long-term performance of the facility was included in the vast documentation that was a part of the application for an operational license. The assessment was presented in the form of a final safety report. In the operational licence for SFR-1 it is stated that renewed safety assessments should be carried out at least each ten years. In order to meet this demand SKB has launched a special project, SAFE (Safety Assessment of Final Disposal of Operational Radioactive Waste). The aim of the project is to update the safety analysis and to prepare a safety report that will be presented to the Swedish authorities not later than year 2000. Project SAFE is divided into three phases. The first phase is a prestudy, and the results of the prestudy are given in this report. The aim of the prestudy is to identify issues where additional studies would improve the basis for the updated safety analysis as well as to suggest how these studies should be carried out. The work has been divided into six different topics, namely the inventory, the near field, the far field, the biosphere, radionuclide transport calculations and scenarios. For each topic the former safety reports and regulatory reviews are scrutinised and needs for additional work is identified. The evaluations are given in appendices covering the respective topics. The main report is a summary of the appendices with a more stringent description of the repository system and the processes that are of interest and therefore should be addressed in an updated safety assessment. However, it should be pointed out that one of the

  10. Dynamic Analysis of a Pyroprocessing Coupled SFR Fuel Recycling

    Directory of Open Access Journals (Sweden)

    Fanxing Gao

    2012-01-01

    Full Text Available Numerous studies have attempted to solve the problems constraining the sustainable utilization of nuclear power, for example, the already accumulated HLWs, the worsening environment due to greenhouse emissions, the questionable reliability of natural uranium resources, and the argument over nuclear safety, which are certainly top issues to be addressed. A well-organized nuclear fuel cycle system is the basis for nuclear power sustainability. Therefore, which type of reactor to be employed and whether or not to adopt a reprocessing technique for spent fuel are two key issues to be addressed. A Sodium Fast Reactor (SFR, a Generation IV reactor, has gained considerable attention worldwide. SFR recycling coupled to pyroprocessing, a so-called Pyro-SFR Recycling, shows promising advantages, and therefore, this paper focuses on exploring a strategy of how to realize it, which can offer informative procedures for a better use of nuclear power. A dynamic model has been developed to quantitatively analyze a country-specific case employing two scenarios, a once-through and Pyro-SFR, for a comprehensive comparison, especially focusing on the uranium utilization, the HLW reduction, and the electricity generation cost.

  11. Rapid core measure improvement through a "business case for quality".

    Science.gov (United States)

    Perlin, Jonathan B; Horner, Stephen J; Englebright, Jane D; Bracken, Richard M

    2014-01-01

    Incentives to improve performance are emerging as revenue or financial penalties are linked to the measured quality of service provided. The HCA "Getting to Green" program was designed to rapidly increase core measure performance scores. Program components included (1) the "business case for quality"-increased awareness of how quality drives financial performance; (2) continuous communication of clinical and financial performance data; and (3) evidence-based clinical protocols, incentives, and tools for process improvement. Improvement was measured by comparing systemwide rates of adherence to national quality measures for heart failure (HF), acute myocardial infarction (AMI), pneumonia (PN), and surgical care (SCIP) to rates from all facilities reporting to the Centers for Medicare and Medicaid Services (CMS). As of the second quarter of 2011, 70% of HCA total measure set composite scores were at or above the 90th percentile of CMS scores. A test of differences in regression coefficients between the CMS national average and the HCA average revealed significant differences for AMI (p = .001), HF (p = .012), PN (p < .001), and SCIP (p = .015). This program demonstrated that presentation of the financial implications of quality, transparency in performance data, and clearly defined goals could cultivate the desire to use improvement tools and resources to raise performance. © 2012 National Association for Healthcare Quality.

  12. Tailoring Sandwich Face/Core Interfaces for Improved Damage Tolerance

    DEFF Research Database (Denmark)

    Lundsgaard-Larsen, Christian; Berggreen, Christian; Carlsson, Leif A.

    2010-01-01

    A face/core debond in a sandwich structure may propagate in the interface or kink into either the face or core. It is found that certain modifications of the face/core interface region influence the kinking behavior, which is studied experimentally in the present paper. A sandwich double cantilever...

  13. Study of the occurrence of organic matter, metals and chemicals in the SFR; Utredning kring foerekomst av organiskt material, metaller och kemikalier i SFR

    Energy Technology Data Exchange (ETDEWEB)

    Sundqvist, J.O. [Swedish Environmental Research Inst., Stockholm (Sweden)

    2001-03-01

    Low- and intermediate level operational waste from the Swedish nuclear power plants, and the Studsvik facility, is currently placed in a repository, termed SFR-l (final repository for radioactive operational waste) near the Forsmark power plant. Two important components in the waste, which can affect the function of the repository, are organic materials, e.g. cloth and paper, and metals (scrap). The release of radionuclides from the repository may be affected by chemical reactions that involve both organic materials and metals. After sealing the repository, the conditions can be such that complexing agents (e.g. isosaccarinic acid) may form when organic materials degrade. These agents typically increase the mobility of radionuclides. Formation of gas, mainly due to metal corrosion, may affect the barrier system, surrounding the waste, such that the release of radionuclides is enhanced. SKB makes an annual report with a compilation of the waste that has been placed in SFR-l . The compilation contains both the amount of waste placed in the repository during the last year and a compilation of the waste that have been placed since the stall of SFR. Moreover, SKB provides a prognosis of the future situation in SFR-1 every third year. SKI (the Swedish Nuclear Power Inspectorate), is responsible for reviewing this reporting. This study was initiated with the purpose of evaluating the uncertainties in SKB's estimates of the amounts of organic matter, metals and chemicals in the waste in SFR- I. The estimates of the quantities of e.g. cellulose and metals in the waste are based on a method which is utilising what is called normal-containers. The waste is classified into certain waste categories. For each waste category there is a specified, presumed composition, named normal-container. The results of this study suggest that the documentation provided by SKB is lacking in some respects. There are for instance examples of incomplete notification of waste and container

  14. The biosphere today and tomorrow in the SFR area

    Energy Technology Data Exchange (ETDEWEB)

    Kautsky, Ulrik (ed.)

    2001-06-01

    This report is a compilation of the work done mainly in the SAFE project for the biosphere from about 14 reports. The SAFE project is the updated safety analysis of SFR-1, the LLW and ILW repository at Forsmark. The aim of the report is to summarize the available information about the present-day biosphere in the area surrounding SFR and to use this information, together with information about the previous development of the biosphere, to predict the future development of the area in a more comparable way than the underlying reports. The data actually used for the models have been taken from the original reports which also justify or validate the data. The report compiles information about climate, oceanography, landscape, sedimentation, shoreline displacement, marine, lake and terrestrial ecosystems.

  15. Verification and validation plan for the SFR system analysis module

    Energy Technology Data Exchange (ETDEWEB)

    Hu, R. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2014-12-18

    This report documents the Verification and Validation (V&V) Plan for software verification and validation of the SFR System Analysis Module (SAM), developed at Argonne National Laboratory for sodium fast reactor whole-plant transient analysis. SAM is developed under the DOE NEAMS program and is part of the Reactor Product Line toolkit. The SAM code, the phenomena and computational models of interest, the software quality assurance, and the verification and validation requirements and plans are discussed in this report.

  16. Supernova Neutrino Background Bound on the SFR History

    CERN Document Server

    Khodagholizadeh, Jafar

    2015-01-01

    The purpose of the present study is to compare the predictions of different models of star formation rate (SFR) history in the universe with the upper limit of Super Kamiokande for the neutrino background. To this aim we have calculated the expected neutrino density for the most popular models of SFR history, Hogg et al. ,Glazebrook et al., Cole et al., Yuksel et al., Hernquist et al. and Kaplinghat et al. Differerent from previous studies we have used the $\\Lambda$CDM model with $\\Omega_{\\Lambda} = 0.7$. We have assumed that the detector used for the detection the neutrino flux is SuperK and also we have assumed that the electron neutrinos produced in the Supernovae oscillate equally to the three standard model flavors. By these assumptions all models stay below the upper limit of SuperK on the event rate and the detection of the supernova relic neutrino background (SRNB) remains undetected. Future neutrino detectors such as KM3Net will be able to detect the SRNB and distinguish between the models of the SFR...

  17. Review of C-14 inventory for the SFR facility

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Graham; Merino, Joan; Kerrigan, Emma

    2002-08-01

    The Swedish Radiation Protection Authority (SSI) is currently reviewing SKB's continuing assessment for disposal of radioactive waste to the SFR facility at Forsmark. Among the wastes disposed are reactor operating wastes. Among the relevant radionuclides is C-14, which is relatively difficult to measure and to control because of its mobility. This report documents a review of the C-14 inventory material submitted by SKB for the SFR-facility, to determine its validity and comment on the appropriate assumptions for C-14 content of wastes due to be disposed of to the SFR. The review is based on information provided by SSI as well as other relevant international experience. Conclusions are drawn upon: the chemical form of the C-14 in the waste from BWRs and PWRs; the production rate of C-14 in BWRs and PWRs and quantification of the source term in the IEX waste; the distribution of the C-14 in the IEX waste from BWR between the resins used for treatment of the primary cooling water and the resins used for treatment of the condensate water; quantification of the uncertainties. A suggestion is made that the C-14 inventory could be better developed based upon a mass balance assessment of all the C-14 produced in reactors, and its ultimate fate in effluent and solid wastes, taking account of the reactor specific operational factors identified in the review as relevant to C-14 inventory assessment.

  18. Improved Rock Core Sample Break-off, Retention and Ejection System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed effort advances the design of an innovative core sampling and acquisition system with improved core break-off, retention and ejection features. Phase 1...

  19. Improved Rock Core Sample Break-off, Retention and Ejection System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed effort advances the design of an innovative core sampling and acquisition system with improved core break-off, retention and ejection features. The...

  20. On-Line Core Thermal-Hydraulic Model Improvement

    Energy Technology Data Exchange (ETDEWEB)

    In, Wang Kee; Chun, Tae Hyun; Oh, Dong Seok; Shin, Chang Hwan; Hwang, Dae Hyun; Seo, Kyung Won

    2007-02-15

    The objective of this project is to implement a fast-running 4-channel based code CETOP-D in an advanced reactor core protection calculator system(RCOPS). The part required for the on-line calculation of DNBR were extracted from the source of the CETOP-D code based on analysis of the CETOP-D code. The CETOP-D code was revised to maintain the input and output variables which are the same as in CPC DNBR module. Since the DNBR module performs a complex calculation, it is divided into sub-modules per major calculation step. The functional design requirements for the DNBR module is documented and the values of the database(DB) constants were decided. This project also developed a Fortran module(BEST) of the RCOPS Fortran Simulator and a computer code RCOPS-SDNBR to independently calculate DNBR. A test was also conducted to verify the functional design and DB of thermal-hydraulic model which is necessary to calculate the DNBR on-line in RCOPS. The DNBR margin is expected to increase by 2%-3% once the CETOP-D code is used to calculate the RCOPS DNBR. It should be noted that the final DNBR margin improvement could be determined in the future based on overall uncertainty analysis of the RCOPS.

  1. Improved synthetic spectra of helium-core white dwarf stars

    CERN Document Server

    Rohrmann, R D; Althaus, L G; Benvenuto, O G

    2002-01-01

    We examine the emergent fluxes from helium-core white dwarfs following their evolution from the end of pre-white dwarf stages down to advanced cooling stages. For this purpose, we include a detailed treatment of the physics of the atmosphere, particularly an improved representation of the state of the gas by taking into account non-ideal effects according to the so-called occupation probability formalism. The present calculations also incorporate hydrogen line opacity from Lyman, Balmer and Paschen series, pseudo-continuum absorptions and new updated induced-dipole absorption from H$_2$-H$_2$, H$_2$-He and H-He pairs. We find that the non-ideal effects and line absorption alter the appearance of the stellar spectrum and have a significant influence upon the photometric colours in the UBVRI-JHKL system. This occurs specially for hot models $T_{\\rm eff}\\ga 8000$ due to line and pseudo-continuum opacities, and for cool models $T_{\\rm eff}\\la 4000$ where the perturbation of atoms and molecules by neighbour partic...

  2. Evaluation of Melt Behavior with initial Melt Velocity under SFR Severe Accidents

    Energy Technology Data Exchange (ETDEWEB)

    Heo, Hyo; Bang, In Cheol [UNIST, Ulsan (Korea, Republic of); Jerng, Dong Wook [Chung-Ang Univ, Seoul (Korea, Republic of)

    2015-10-15

    In the current Korean sodium-cooled fast reactor (SFR) program, early dispersion of the molten metallic fuel within a subchannel is suggested as one of the inherent safety strategies for the initiating phase of hypothetical core disruptive accident (HCDA). The safety strategy provides negative reactivity driven by the melt dispersal, so it could reduce the possibility of the recriticality event under a severe triple or more fault scenario for SFR. Since the behavior of the melt dispersion is unpredictable, it depends on the accident condition, particularly core region. While the voided coolant channel region is usually developed in the inner core, the unvoided coolant channel region is formed in the outer core. It is important to confirm the fuel dispersion with the core region, but there are not sufficient existing studies for them. From the existing studies, the coolant vapor pressure is considered as one of driving force to move the melt towards outside of the core. There is a complexity of the phenomena during intermixing of the melt with the coolant after the horizontal melt injections. It is too difficult to understand the several combined mechanisms related to the melt dispersion and the fragmentation. Thus, it could be worthwhile to study the horizontal melt injections at lower temperature as a preliminary study in order to identify the melt dispersion phenomena. For this reason, it is required to clarify whether the coolant vapor pressure is the driving force of the melt dispersion with the core region. The specific conditions to be well dispersed for the molten metallic fuel were discussed in the experiments with the simulant materials. The each melt behavior was compared to evaluate the melt dispersion under the coolant void condition and the boiling condition. As the results, the following results are remarked: 1. The upward melt dispersion did not occur for a given melt and coolant temperature in the nonboiling range. Over current range of conditions

  3. Tailoring Sandwich Face/Core Interfaces for Improved Damage Tolerance

    DEFF Research Database (Denmark)

    Lundsgaard-Larsen, Christian; Berggreen, Christian; Carlsson, Leif A.

    2010-01-01

    Various modifications of the face/core interface in foam core sandwich specimens are examined in a series of two papers. This paper constitutes part I and describes the finite element analysis of a sandwich test specimen, i.e. a DCB specimen loaded by uneven bending moments (DCB-UBM). Using...

  4. Dynamical analysis of innovative core designs facing unprotected transients with the MAT5 DYN code

    Energy Technology Data Exchange (ETDEWEB)

    Darmet, G.; Massara, S. [EDF R and D, 1 avenue du general de Gaulle, 92140 Clamart (France)

    2012-07-01

    Since 2007, advanced Sodium-cooled Fast Reactors (SFR) are investigated by CEA, AREVA and EDF in the framework of a joint French collaboration. A prototype called ASTRID, sets out to demonstrate progress made in SFR technology, is due to operate in the years 2020's. The modeling of unprotected transients by computer codes is one of the key safety issues in the design approach to such SFR systems. For that purpose, the activity on CATHARE, which is the reference code for the transient analysis of ASTRID, has been strengthened during last years by CEA. In the meantime, EDF has developed a simplified and multi-channel code, named MAT5 DYN, to analyze and validate innovative core designs facing protected and unprotected transients. First, the paper consists in a description of MAT5 DYN: a code based on the existing code MAT4 DYN including major improvements on geometry description and physical modeling. Second, two core designs based on the CFV core design developed at CEA are presented. Then, the dynamic response of those heterogeneous cores is analyzed during unprotected loss of flow (ULOF) transient and unprotected transient of power (UTOP). The results highlight the importance of the low void core effect specific to the CFV design. Such an effect, when combined with a sufficient primary pump halving time and an optimized cooling group scheme, allows to delay (or, possibly, avoid) the sodium boiling onset during ULOF accidents. (authors)

  5. Assessment of the long-term safety for SFR

    Energy Technology Data Exchange (ETDEWEB)

    Greis Dahlberg, Christina; Vahlund, Frederik [Svensk Kaernbraenslehantering AB, Stockholm (Sweden)

    2015-07-01

    During operation and decommissioning of the Swedish nuclear facilities, radioactive waste is generated that must be disposed of. Besides waste from the nuclear facilities, some waste derives from other activities such as industry, research, medical care, etc. Short-lived low- and intermediate-level waste from these activities is disposed of in the final repository for short-lived radioactive waste, SFR, in Forsmark. The facility, which has been in operation since 1988, is owned and operated by Svensk Karnbranslehantering AB, SKB. The existing facility has neither sufficient space nor a license to receive decommissioning waste. SFR must therefore be extended so that shortlived low- and intermediate-level decommissioning waste from the nuclear facilities can also be received. The need for additional capacity has been accentuated by the closure of two reactors in Barseback. These reactors cannot be dismantled until the SFR facility has been extended. The existing repository is built to receive, and after closure serve as a passive repository for, low- and intermediate-level radioactive waste. The disposal rooms are situated in the bedrock beneath the sea floor, covered by about 60 metres of rock. The repository has been designed so that it can be abandoned after closure without requiring further measures to maintain its function. The extension of SFR, is done at the -120 m level immediately adjacent to, and within the same depth range as, the existing facility. The basic function of the existing SFR and of the extended one will be the same. However, a clear difference is the design of the tunnel and the rock vault that are required to permit transport and storage of whole reactor pressure vessels. The application for a license to build this extension includes an assessment of the long-term safety (post-closure safety) of the facility. The safety assessment also contains an updated assessment of the long-term safety of the existing facility. The safety assessment for

  6. Bedrock Hydrogeology - Groundwater flow modelling. Site investigation SFR

    Energy Technology Data Exchange (ETDEWEB)

    Oehman, Johan [Geosigma AB, Uppsala (Sweden); Follin, Sven [SF GeoLogic AB, Taeby (Sweden); Oden, Magnus [SKB, Stockholm (Sweden)

    2013-05-15

    The hydrogeological model developed for the SFR extension project (PSU) consists of 40 geologically modelled deformation zones (DZ) and 8 sub-horizontal structural-hydraulic features, called SBAstructures, not defined in the geological model. However, some of the SBA-structures coincide with what is defined as unresolved possible deformation zones (Unresolved PDZ) in the geological modelling. In addition, the hydrogeological model consists of a stochastic discrete fracture network (DFN) model intended for the less fractured rock mass volumes (fracture domains) between the zones and the SBA-structures, and a stochastic fracture model intended to handle remaining Unresolved PDZs in the geological modelling not modelled as SBA-structures in the hydrogeological modelling. The four structural components of the bedrock in the hydrogeological model, i.e. DZ, SBA, Unresolved PDZ and DFN, are assigned hydraulic properties in the hydrogeological model based on the transmissivities interpreted from single-hole hydraulic tests. The main objective of the present work is to present the characteristics of the hydrogeological model with regard to the needs of the forthcoming safety assessment SR-PSU. In concrete words, simulated data are compared with measured data, i.e. hydraulic heads in boreholes and tunnel inflow to the existing repository (SFR). The calculations suggest that the available data for flow model calibration cannot be used to motivate a substantial adjustment of the initial hydraulic parameterisation (assignment of hydraulic properties) of the hydrogeological model. It is suggested that uncertainties in the hydrogeological model are studied in the safety assessment SR-PSU by means of a large number of calculation cases. These should address hydraulic heterogeneity of deterministic structures (DZ and SBA) and realisations of stochastic fractures/fracture networks (Unresolved PDZ and DFN) within the entire SFR Regional model domain.

  7. The Thermal Hydraulic Test of SFR Irradiation Test Capsule

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chul Yong; Park, Sung Jae; Choo, Kee Nam [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-10-15

    Irradiation test using a capsule has been performed for fuel or material performance test in the test reactor. Irradiation capsule for the HANARO reactor must satisfy the hydraulic conditions and structural integrity from a out-pile test. Items of a out-pile test are pressure drop, flow-induced vibration test and endurance test. The results of test must show that a test capsule satisfy the HANARO operational requirement with sufficient margin. This paper describes the devices of thermal hydraulic test and the results of SFR test capsule

  8. Analysis of Reactor Deployment Scenarios with Introduction of SFR Breakeven Reactors and Burners Using DANESS Code

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young In; Hahn, Do Hee; Won, Byung Chool; Lee, Dong Uk

    2008-01-15

    Using the DANESS code newly employed for future scenario analysis, reactor deployment scenarios with the introduction of sodium cooled fast reactors(SFRs) having different conversion ratios in the existing PWRs dominant nuclear fleet have been analyzed to find the SFR deployment strategy for replacing PWRs with the view of a spent fuel reduction and an efficient uranium utilization through its reuse in a closed nuclear fuel cycle. Descriptions of the DANESS code and how to use are briefly given from the viewpoint of its first application. The use of SFRs and recycling of TRUs by reusing PWR spent fuel leads to the substantial reduction of the amount of PWR spent fuel and environmental burden by decreasing radiotoxicity of high level waste, and a significant improvement on the natural uranium resources utilization. A continuous deployment of burners effectively decreases the amount of PWR spent fuel accumulation, thus lightening the burden for PWR spent fuel management. An introduction of breakeven reactors effectively reduces the uranium demand through producing excess TRU during the operation, thus contributing to a sustainable nuclear power development. With SFR introduction starting in 2040, PWRs will remain as a main power reactor type till 2100 and SFRs will be in support of waste minimization and fuel utilization.

  9. An Accurate Simulation Of Thermoforming And Blow-Molding Processes Using The Space Fiber Rotation (SFR) Concept

    Science.gov (United States)

    Ghomari, T.; Ayad, R.; Talbi, N.

    2007-05-01

    This work deals with a non-linear formulation of an axisymmetric hyperelastic solid model for thermoforming and blow-molding processes. It's based on a new kinematic concept labeled SFR (Space Fiber Rotation). The SFR-Axi element model uses a kinematic motion of a space linear fiber in order to obtain more accurate displacement field, without increasing the number of nodes. It improves in a significant way the precision of the linear element Q4 indeed. The corresponding numerical results are comparable and even better, in term of time CPU, with those of the 8-nodes higher order element Q8. A hyperelastic behavior law based on Mooney-Rivlin model has been implemented to allow the model better simulations of forming processes hollow plastic bodies. The numerical results, very promising, are given with considering or not the contact between the polymer.

  10. Thermal properties of SFR-HPC exposed to high temperatures

    Science.gov (United States)

    Scheinherrová, Lenka; Pavlík, Zbyšek

    2017-07-01

    In this paper, a non-adiabatic method was used for the assessment of specific heat capacity of steel fibre reinforced high performance concrete in the temperature range 105-1000 °C. The tested SFR-HPC mix was produced from CEM II 42.5 R, ground granulated blast furnace slag, silica sand with maximum particle size of 2 mm, silica fume, brass-coated steel fibres, superplasticizer on polycarboxylate ether basis and batch water. For the studied material, properties after 2 hours thermal treatment at the temperatures of 105 °C, 200 °C, 400 °C, 600 °C, 800 °C, and 1000 °C respectively were tested. Among them, bulk density, matrix density, total open porosity and thermal parameters as thermal conductivity, thermal diffusivity and specific heat capacity were measured. The measured specific heat capacity exhibited high dependence on temperature and pointed to the structural changes that studied material underwent at high temperatures. Accordingly, the obtained residual parameters revealed the thermally induced damage of SFR-HPC and critical temperatures for its functionality.

  11. Improved Multi-Core Nested Depth-First Search

    NARCIS (Netherlands)

    Evangelista, Sami; Laarman, Alfons; Petrucci, Laure; Pol, van de Jaco; Ramesh, S.

    2012-01-01

    This paper presents CNDFS, a tight integration of two earlier multi-core nested depth-first search (NDFS) algorithms for LTL model checking. CNDFS combines the different strengths and avoids some weaknesses of its predecessors. We compare CNDFS to an earlier ad-hoc combination of those two algorithm

  12. Improved Multi-Core Nested Depth-First Search

    NARCIS (Netherlands)

    Evangelista, Sami; Laarman, Alfons; Petrucci, Laure; van de Pol, Jan Cornelis; Ramesh, S.

    2012-01-01

    This paper presents CNDFS, a tight integration of two earlier multi-core nested depth-first search (NDFS) algorithms for LTL model checking. CNDFS combines the different strengths and avoids some weaknesses of its predecessors. We compare CNDFS to an earlier ad-hoc combination of those two

  13. Conceptual Design Study on Electromagnets of Control Rod Drive Mechanism of a SFR

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jaehan; Koo, Gyeonghoi [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    The prototype SFR has six primary control rod assemblies(CRAs) and three secondary shutdown assemblies. The primary control system is used for power control, burnup compensation and reactor shutdown in response to demands from the plant control or protection systems. This paper describes the design concept of primary control rod drive mechanism shortly, and performs the parametric design studies for the electromagnet device of the drive mechanism to maximize CRA gripping force. The electromagnetic core usually confines and guides the magnetic field. The major parameters influenced on the electromagnetic force are the geometry and arrangement of the electromagnet and armature for a given coil specification. A typical equation calculating the electromagnetic force for a solenoid type is represented in equation. The first one is the increasing of the flux cross section area (Α{sub c}, Α{sub g}) in magnetic field connecting of air gap, armature and electromagnets. Secondly, the reducing of the path lengths (l{sub c}, l{sub g}) of the armature and electromagnet makes the magnetic flux (Β) resistance to be low. An electromagnet field analyses are performed for the initial design values of the electromagnet device. The gripping force is about 3 times of CRA weight when one coil is power on. The parametric studies on air gap, core sizes configuring of the electromagnet cores are performed to maximize the electromagnetic force.

  14. DNA homologous recombination factor SFR1 physically and functionally interacts with estrogen receptor alpha.

    Directory of Open Access Journals (Sweden)

    Yuxin Feng

    Full Text Available Estrogen receptor alpha (ERα, a ligand-dependent transcription factor, mediates the expression of its target genes by interacting with corepressors and coactivators. Since the first cloning of SRC1, more than 280 nuclear receptor cofactors have been identified, which orchestrate target gene transcription. Aberrant activity of ER or its accessory proteins results in a number of diseases including breast cancer. Here we identified SFR1, a protein involved in DNA homologous recombination, as a novel binding partner of ERα. Initially isolated in a yeast two-hybrid screen, the interaction of SFR1 and ERα was confirmed in vivo by immunoprecipitation and mammalian one-hybrid assays. SFR1 co-localized with ERα in the nucleus, potentiated ER's ligand-dependent and ligand-independent transcriptional activity, and occupied the ER binding sites of its target gene promoters. Knockdown of SFR1 diminished ER's transcriptional activity. Manipulating SFR1 expression by knockdown and overexpression revealed a role for SFR1 in ER-dependent and -independent cancer cell proliferation. SFR1 differs from SRC1 by the lack of an intrinsic activation function. Taken together, we propose that SFR1 is a novel transcriptional modulator for ERα and a potential target in breast cancer therapy.

  15. CORE

    DEFF Research Database (Denmark)

    Krigslund, Jeppe; Hansen, Jonas; Hundebøll, Martin

    2013-01-01

    different flows. Instead of maintaining these approaches separate, we propose a protocol (CORE) that brings together these coding mechanisms. Our protocol uses random linear network coding (RLNC) for intra- session coding but allows nodes in the network to setup inter- session coding regions where flows...... intersect. Routes for unicast sessions are agnostic to other sessions and setup beforehand, CORE will then discover and exploit intersecting routes. Our approach allows the inter-session regions to leverage RLNC to compensate for losses or failures in the overhearing or transmitting process. Thus, we...... increase the benefits of XORing by exploiting the underlying RLNC structure of individual flows. This goes beyond providing additional reliability to each individual session and beyond exploiting coding opportunistically. Our numerical results show that CORE outperforms both forwarding and COPE...

  16. CORE

    DEFF Research Database (Denmark)

    Krigslund, Jeppe; Hansen, Jonas; Hundebøll, Martin

    2013-01-01

    different flows. Instead of maintaining these approaches separate, we propose a protocol (CORE) that brings together these coding mechanisms. Our protocol uses random linear network coding (RLNC) for intra- session coding but allows nodes in the network to setup inter- session coding regions where flows...... intersect. Routes for unicast sessions are agnostic to other sessions and setup beforehand, CORE will then discover and exploit intersecting routes. Our approach allows the inter-session regions to leverage RLNC to compensate for losses or failures in the overhearing or transmitting process. Thus, we...... increase the benefits of XORing by exploiting the underlying RLNC structure of individual flows. This goes beyond providing additional reliability to each individual session and beyond exploiting coding opportunistically. Our numerical results show that CORE outperforms both forwarding and COPE...

  17. Edge-core interplay in transition to radiative improved mode

    Energy Technology Data Exchange (ETDEWEB)

    Tokar, M.Z.; Unterberg, B. [Association Euratom-Forschungszentrum Juelich GmbH (Germany). Inst. fuer Plasmaphysik; Jaspers, R. [Associatie Euratom-FOM, Nieuwegein (Netherlands). FOM-Instituut voor Plasmafysica

    1998-05-01

    A new radiative improved-mode (RI-mode) has been found in TEXTOR-94 in experiments aimed to prove feasibility of the concept of a radiating plasma mantle under quasi-stationary conditions of auxiliary heated discharges. By puffing of neon, silane or argon, up to 95% of the total input power can be radiated without detachment of the plasma from the limiter. Contrary to the common belief, the high edge radiation level does not lead to a degradation of the energy confinement, but can cause a substantial improvement with an appropriate heating and operational scenario. Investigation of the mechanisms of the confinement improvement in the RI-mode by means of predictive transport modeling is the aim of this contribution. (orig.) 6 refs.

  18. MSFR TRU-burning potential and comparison with an SFR

    Energy Technology Data Exchange (ETDEWEB)

    Fiorina, C.; Cammi, A. [Politecnico di Milano: Via La Masa 34, 20136 Milan (Italy); Franceschini, F. [Westinghouse Electric Company LL: 1000 Westinghouse Dr., Cranberry Township, PA 16066 (United States); Krepel, J. [Paul Scherrer Institut - PSI WEST, 5234 Villigen (Switzerland)

    2013-07-01

    The objective of this work is to evaluate the Molten Salt Fast Reactor (MSFR) potential benefits in terms of transuranics (TRU) burning through a comparative analysis with a sodium-cooled FR. The comparison is based on TRU- and MA-burning rates, as well as on the in-core evolution of radiotoxicity and decay heat. Solubility issues limit the TRU-burning rate to 1/3 that achievable in traditional low-CR FRs (low-Conversion-Ratio Fast Reactors). The softer spectrum also determines notable radiotoxicity and decay heat of the equilibrium actinide inventory. On the other hand, the liquid fuel suggests the possibility of using a Pu-free feed composed only of Th and MA (Minor Actinides), thus maximizing the MA burning rate. This is generally not possible in traditional low-CR FRs due to safety deterioration and decay heat of reprocessed fuel. In addition, the high specific power and the lack of out-of-core cooling times foster a quick transition toward equilibrium, which improves the MSFR capability to burn an initial fissile loading, and makes the MSFR a promising system for a quick (i.e., in a reactor lifetime) transition from the current U-based fuel cycle to a novel closed Th cycle. (authors)

  19. A study on improving the performance of a research reactor's equilibrium core

    Directory of Open Access Journals (Sweden)

    Muhammad Atta

    2013-01-01

    Full Text Available Utilizing low enriched uranium silicide fuel (U3Si2-Al of existing uranium density (3.285 g/cm3, different core configurations have been studied in search of an equilibrium core with an improved performance for the Pakistan Research Reactor-1. Furthermore, we have extended our analysis to the performance of higher density silicide fuels with a uranium density of 4.0 and 4.8 U g/cm3. The criterion used in selecting the best performing core was that of “unit flux time cycle length per 235U mass per cycle”. In order to analyze core performance by improving neutron moderation, utilizing higher-density fuel, the effect of the coolant channel width was also studied by reducing the number of plates in the standard/control fuel element. Calculations employing computer codes WIMSD/4 and CITATION were performed. A ten energy group structure for fission neutrons was used for the generation of microscopic cross-sections through WIMSD/4. To search the equilibrium core, two-dimensional core modelling was performed in CITATION. Performance indicators have shown that the higher-density uranium silicide-fuelled core (U density 4.8 g/cm3 without any changes in standard/control fuel elements, comprising of 15 standard and 4 control fuel elements, is the best performing of all analyzed cores.

  20. Improvement of Axial Reflector Cross Section Generation Model for PWR Core Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shim, Cheon Bo; Lee, Kyung Hoon; Cho, Jin Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    This paper covers the study for improvement of axial reflector XS generation model. In the next section, the improved 1D core model is represented in detail. Reflector XS generated by the improved model is compared to that of the conventional model in the third section. Nuclear design parameters generated by these two XS sets are also covered in that section. Significant of this study is discussed in the last section. Two-step procedure has been regarded as the most practical approach for reactor core designs because it offers core design parameters quite rapidly within acceptable range. Thus this approach is adopted for SMART (System-integrated Modular Advanced Reac- Tor) core design in KAERI with the DeCART2D1.1/ MASTER4.0 (hereafter noted as DeCART2D/ MASTER) code system. Within the framework of the two-step procedure based SMART core design, various researches have been studied to improve the core design reliability and efficiency. One of them is improvement of reflector cross section (XS) generation models. While the conventional FA/reflector two-node model used for most core designs to generate reflector XS cannot consider the actual configuration of fuel rods that intersect at right angles to axial reflectors, the revised model reflects the axial fuel configuration by introducing the radially simplified core model. The significance of the model revision is evaluated by observing HGC generated by DeCART2D, reflector XS, and core design parameters generated by adopting the two models. And it is verified that about 30 ppm CBC error can be reduced and maximum Fq error decreases from about 6 % to 2.5 % by applying the revised model. Error of AO and axial power shapes are also reduced significantly. Therefore it can be concluded that the simplified 1D core model improves the accuracy of the axial reflector XS and leads to the two-step procedure reliability enhancement. Since it is hard for core designs to be free from the two-step approach, it is necessary to find

  1. Electrical Core Transformer for Grid Improvement Incorporating Wire Magnetic Components

    Energy Technology Data Exchange (ETDEWEB)

    Harrie R. Buswell, PhD; Dennis Jacobs, PhD; Steve Meng

    2012-03-26

    The research reported herein adds to the understanding of oil-immersed distribution transformers by exploring and demonstrating potential improvements in efficiency and cost utilizing the unique Buswell approach wherein the unit is redesigned, replacing magnetic sheet with wire allowing for improvements in configuration and increased simplicity in the build process. Exploration of new designs is a critical component in our drive to assure reduction of energy waste, adequate delivery to the citizenry, and the robustness of U.S. manufacturing. By moving that conversation forward, this exploration adds greatly to our base of knowledge and clearly outlines an important avenue for further exploration. This final report shows several advantages of this new transformer type (outlined in a report signed by all of our collaborating partners and included in this document). Although materials development is required to achieve commercial potential, the clear benefits of the technology if that development were a given is established. Exploration of new transformer types and further work on the Buswell design approach is in the best interest of the public, industry, and the United States. Public benefits accrue from design alternatives that reduce the overall use of energy, but it must be acknowledged that new DOE energy efficiency standards have provided some assurance in that regard. Nonetheless the burden of achieving these new standards has been largely shifted to the manufacturers of oil-immersed distribution transformers with cost increasing up to 20% of some units versus 2006 when this investigation was started. Further, rising costs have forced the industry to look closely are far more expensive technologies which may threaten U.S. competitiveness in the distribution transformer market. This concern is coupled with the realization that many units in the nation's grid are beyond their optimal life which suggests that the nation may be headed for an infrastructure

  2. Core/shell composites with polystyrene cores and meso-silica shells as abrasives for improved chemical mechanical polishing behavior

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yang, E-mail: cy.jpu@126.com; Qin, Jiawei; Wang, Yayun; Li, Zefeng [Changzhou University, School of Material Science and Engineering (China)

    2015-09-15

    The core/shell-structured organic/inorganic composite abrasive has an important potential application in damage-free chemical mechanical polishing (CMP) due to its non-rigid mechanical property. In this work, the PS/{sub M}SiO{sub 2} composites, containing polystyrene (PS) sphere (211 ± 4 nm) cores and mesoporous silica shells (31 ± 3 nm in thickness) were synthesized through directed surface sol–gel process of tetraethylorthosilicate on the polymer cores in the presence of the cetyltrimethylammonium bromide surfactant. For comparison, the conventional core/shell PS/{sub N}SiO{sub 2} composites with non-porous silica shells were also prepared via a modified Stöber procedure that involved the hydrolysis of TEOS under acidic condition. The physical properties of the samples were examined by small-angle X-ray diffraction, fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy, field emission scanning electron microscopy, and nitrogen adsorption–desorption. As novel abrasives, the core/shell-structured PS/{sub M}SiO{sub 2} composites were introduced into the CMP process for silicon oxide films. The oxide-CMP performance among conventional solid silica particles, PS/{sub N}SiO{sub 2} composites, and novel PS/{sub M}SiO{sub 2} composites was explored by atomic force microscopy. Polishing results indicated that the substrate revealed a comparable root-mean-square surface roughness (0.25 ± 0.03 and 0.22 ± 0.02 nm, respectively) after CMP with PS/{sub N}SiO{sub 2} and PS/{sub M}SiO{sub 2} abrasives under the same polishing conditions. However, the material removal rate of the PS/{sub M}SiO{sub 2} composites (123 ± 15 nm/min) was about three times larger than that of the PS/{sub N}SiO{sub 2} composites (47 ± 13 nm/min). The reduced surface roughness and improved removal rate might be due to the optimization of the physical and/or chemical environments in the local contacting region between abrasives

  3. Improving Packet Processing Efficiency on Multi-core Architectures with Single Input Queue

    Directory of Open Access Journals (Sweden)

    Peter Orosz

    2012-06-01

    Full Text Available Generic purpose multi-core PC architectures are facing performance challenges of high rate packet reception on gigabit per second and higher speed network interfaces. In order to assign a CPU core to a networking softIRQ, the single input queue design of the low-level packet processing subsystem relies on the kernel's Symmetric Multiprocessing (SMP scheduler, which does not perform load balancing of the softIRQ instances between the CPU cores. In practice, when single receive queue is used all of the softIRQs are assigned to a single CPU core. This typical arrangement could easily drive to CPU resource exhaustion and high packet loss ratio on high bandwidth interfaces. The non-steady state of the system is triggered by the high arrival rate of the packets. This work presents a proposal for improving the packet processing efficiency in single input queue multi-core systems.

  4. Basic Design of Experimental Facility for Measuring Pressure Drop of IHX in a SFR

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Yung-Joo; Eoh, Jae-Hyuk; Kim, Hyungmo; Lee, Dong-Won; Jeong, Ji-Young; Lee, Hyeong-Yeon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Dong Eok [Kyungpook National Univ., Daegu (Korea, Republic of)

    2015-05-15

    The conceptual design of the Prototype gen-IV SFR (PGSFR) with a 150 MWe capacity was commenced in 2012 through the national long-term R and D program by KAERI. Then, PGSFR is now being designed with the defense in depth concept with active, passive and inherent safety features to acquire design approval for PGSFR from the Korean regulatory authority by 2020. PGSFR is a sodium-cooled pool-type fast reactor with all primary components including the primary heat transport system (PHTS) pumps and IHXs are located inside a sodium pool. The heat produced due to fission in the core is transported by primary sodium to secondary sodium in a sodium to sodium intermediate heat exchanger (IHX), which in turn is transferred to water in a steam generator (SG). Basic design of the IHX flow characteristic test facility, WEIPA was conducted based on the three-level scaling methodology in order to preserve the flow characteristics of the IHX in PGSFR. This test facility is intended to measure a high precision pressure drop at the shell-side of the IHX. This paper describes the aspects of the current design features of the IHX in PGSFR, scaling and basic design features of the facility.

  5. Perspectives on Validation and Uncertainty Evaluation of SFR Nuclear Design Code

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Moohoon; Choi, Yong Won; Shin, Andong; Suh, Namduk [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2014-05-15

    Fast reactors such as PGSFR (Prototype Gen-IV Sodium-cooled Fast Reactor) developed by KAERI have fundamental differences in terms of core characteristics and associated fuel cycle compared to thermal reactors, which need specific new effort for code validation. In current PWRs, nuclear design code systems have been validated using numerous data accumulated by wide operating experience, and its uncertainty can be assessed by statistical methods. However, in order to validate code systems for SFRs with little operating experience, and particularly prototype reactor, new approaches are required. In this study, a current procedure for validation and uncertainty evaluation is reviewed in nuclear design code systems for PWRs, and global approaches for validation of SFR code systems are surveyed. Through these reviews, perspectives on nuclear design code validation for SFRs are identified. In case of neutronics code V and V, current procedure for PWRs and global approaches for SFRs were reviewed and surveyed. Though this review, perspectives on nuclear design code V and V and uncertainty evaluation for SFRs were identified. Further study will be implemented to obtain more insight on code validation.

  6. Sodium fast reactor evaluation: Core materials

    Science.gov (United States)

    Cheon, Jin Sik; Lee, Chan Bock; Lee, Byoung Oon; Raison, J. P.; Mizuno, T.; Delage, F.; Carmack, J.

    2009-07-01

    In the framework of the Generation IV Sodium Fast Reactor (SFR) Program the Advanced Fuel Project has conducted an evaluation of the available fuel systems supporting future sodium cooled fast reactors. In this paper the status of available and developmental materials for SFR core cladding and duct applications is reviewed. To satisfy the Generation IV SFR fuel requirements, an advanced cladding needs to be developed. The candidate cladding materials are austenitic steels, ferritic/martensitic (F/M) steels, and oxide dispersion strengthened (ODS) steels. A large amount of irradiation testing is required, and the compatibility of cladding with TRU-loaded fuel at high temperatures and high burnup must be investigated. The more promising F/M steels (compared to HT9) might be able to meet the dose requirements of over 200 dpa for ducts in the GEN-IV SFR systems.

  7. Effect of the Boron and Nitrogen on precipitation behavior in modified 9Cr steel for SFR fuel cladding after aging

    Energy Technology Data Exchange (ETDEWEB)

    Jeog, Eun-Hee; Kim, Young Do [Hanyang University, Seoul (Korea, Republic of); Kim, Sung Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Ferritic-martensitic steels are being considered as an attractive candidate material for a fuel cladding of a SFR due to their low expansion coefficients, high thermal conductivities and excellent irradiation resistances against void swelling. Because of its superior dimensional stability against fast neutron irradiation, Ferritic-martensitic steel of 9Cr and 12Cr steels are preferable to utilize in the fuel cladding of an SFR in KAERI. The soluble boron reduces the coarsening rate of M{sub 23}C{sub 6} carbides along boundaries near prior austenite grain boundaries during creep, enhancing the boundary and sub-boundary hardening for up to long times. The enhancement of boundary and sub-boundary hardening retards the onset of acceleration creep, which decreases the minimum creep rate and improves the creep life. It has been reported that the excess addition of boron and nitrogen promotes the formation of boron nitrides during normalizing heat treatment, which significantly reduces soluble B and N concentrations and offsets the benefit due to boron and nitrogen. In this study, comparison of the microstructure and mechanical properties on SFR fuel cladding steel with different B and N contents after aging were carried out. The addition of B stabilizes the M{sub 23}C{sub 6}, hence the coarsening of M{sub 23}C{sub 6} was not observed in alloy 1 after 7000 hours aging. The size distribution of an alloy 2 was not largely changed with aging time, and this phenomena would be caused by an addition of nitrogen, by stabilize the nitride precipitates such as MX and M{sub 2}X.

  8. Modified Y-TZP core design improves all-ceramic crown reliability.

    Science.gov (United States)

    Silva, N R F A; Bonfante, E A; Rafferty, B T; Zavanelli, R A; Rekow, E D; Thompson, V P; Coelho, P G

    2011-01-01

    This study tested the hypothesis that all-ceramic core-veneer system crown reliability is improved by modification of the core design. We modeled a tooth preparation by reducing the height of proximal walls by 1.5 mm and the occlusal surface by 2.0 mm. The CAD-based tooth preparation was replicated and positioned in a dental articulator for core and veneer fabrication. Standard (0.5 mm uniform thickness) and modified (2.5 mm height lingual and proximal cervical areas) core designs were produced, followed by the application of veneer porcelain for a total thickness of 1.5 mm. The crowns were cemented to 30-day-aged composite dies and were either single-load-to-failure or step-stress-accelerated fatigue-tested. Use of level probability plots showed significantly higher reliability for the modified core design group. The fatigue fracture modes were veneer chipping not exposing the core for the standard group, and exposing the veneer core interface for the modified group.

  9. Analysis of power ramp rate and minimum power controllability of the MMS model for a plant dynamics analysis of a Prototype SFR

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eui Kwang; Kim, Dehee; Joo, Hyungkook; Lee, Taeho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    A full plant dynamic model was developed for a prototype SFR using the Modular Modeling System (MMS). It includes the modeling of various subsystems such as the neutronics, primary and intermediate sodium systems of the NSSS, steam and water systems of the BOP, BOP controls, and the supervisory plant controls. The NSSS model is subdivided into component models, such as a Core, IHXs, Pumps, SGs, and the rest of the NSSS loop model. The BOP model is subdivided into a steam subsystem, feedwater subsystem, and preheater subsystem. Plant transient tests were performed to study the operational considerations. It includes varying the power ramp rate and studying the controllability at minimum power. Plant transient tests were performed to study operational considerations by using the MMS model for a prototype SFR. It includes varying the power ramp rate, studying the controllability at the minimum power set point. At a power ramp rate of higher than 2%, the steam temperature has a large deviation from the target. As the power set point decreases, the PHTS hot leg temperature and steam temperature tend to have higher deviations. After further refinement of the MMS model, it can be useful for developing the plant operation logics of the prototype SFR.

  10. GAMA/H-ATLAS: A meta-analysis of SFR indicators - comprehensive measures of the SFR-M* relation and Cosmic Star Formation History at z < 0.4

    CERN Document Server

    Davies, L J M; Robotham, A S G; Grootes, M W; Popescu, C C; Tuffs, R J; Hopkins, A; Alpaslan, M; Andrews, S K; Bland-Hawthorn, J; Bremer, M N; Brough, S; Brown, M J I; Cluver, M E; Croom, S; da Cunha, E; Dunne, L; Lara-Lopez, M A; Liske, J; Loveday, J; Moffett, A J; Owers, M; Phillipps, S; Sansom, A E; Taylor, E N; Michalowski, M J; Ibar, E; Smith, M; Bourne, N

    2016-01-01

    We present a meta-analysis of star-formation rate (SFR) indicators in the GAMA survey, producing 12 different SFR metrics and determining the SFR-M* relation for each. We compare and contrast published methods to extract the SFR from each indicator, using a well-defined local sample of morphologically-selected spiral galaxies, which excludes sources which potentially have large recent changes to their SFR. The different methods are found to yield SFR-M* relations with inconsistent slopes and normalisations, suggesting differences between calibration methods. The recovered SFR-M* relations also have a large range in scatter which, as SFRs of the targets may be considered constant over the different timescales, suggests differences in the accuracy by which methods correct for attenuation in individual targets. We then recalibrate all SFR indicators to provide new, robust and consistent luminosity-to-SFR calibrations, finding that the most consistent slopes and normalisations of the SFR-M* relations are obtained...

  11. HCV core protein represses the apoptosis and improves the autophagy of human hepatocytes

    Science.gov (United States)

    Liu, Changhong; Qu, Aihua; Han, Xiaochun; Wang, Yiguo

    2015-01-01

    Objectives: This study aims to investigate the influence on human hepatocytes apoptosis and autophagy by the hepatitis C virus (HCV) core protein. Methods: QSG-7701, a human-derived non-neoplastic liver cell line, was transfected with PIRES-core vector that was a eukaryotic vector to express HCV core protein. Fluorescence microscope was used to observe the changes of nuclei in apoptosis cells by Annex in V-FITC/PI double staining. Flow cytometry was applied to detect the rate of cell apoptosis. Western blotting was used to detect the expression of HCV core protein, transcription factor nuclear factor-kappa B (NF-κB), autophagic biomarker microtubule associated protein 1 light chain 3 (LC3), and Beclin-1. Results: The apoptosis rate was significantly lower (P < 0.05) in QSG7701/core group (transfected with PIRES-core vector, (1.34±0.07)%) than in QSG7701 group (no transfection, (2.35±0.11)%) and in QSG7701 QSG7701/pcDNA3.1 group (transfected with pcDNA3.1 vector, (2.58±0.1)%). NF-κB expression was up-expressed in QSG7701/core group than in QSG7701/pcDNA3.1 group and QSG7701 group (P < 0.05). LC3-II expression and Beclin-1 expression was significant higher in QSG7701/core group than in the QSG7701/pcDNA3.1 group and QSG7701 group (P < 0.05). Conclusion: HCV core protein can repress the apoptosis and improve the autophagy of QSG7701 through up-regulating NF-κB and Beclin-1 expression. PMID:26629077

  12. Improvements to an Electrical Engineering Skill Audit Exam to Improve Student Mastery of Core EE Concepts

    Science.gov (United States)

    Parent, D. W.

    2011-01-01

    The San Jose State University Electrical Engineering (EE) Department implemented a skill audit exam for graduating seniors in 1999 with the purpose of assessing the teaching and the students' mastery of core concepts in EE. However, consistent low scores for the first years in which the test was administered suggested that students had little…

  13. Improvement of open and semi-open core wall system in tall buildings by closing of the core section in the last story

    Science.gov (United States)

    Kheyroddin, A.; Abdollahzadeh, D.; Mastali, M.

    2014-09-01

    Increasing number of tall buildings in urban population caused development of tall building structures. One of the main lateral load resistant systems is core wall system in high-rise buildings. Core wall system has two important behavioral aspects where the first aspect is related to reduce the lateral displacement by the core bending resistance and the second is governed by increasing of the torsional resistance and core warping of buildings. In this study, the effects of closed section core in the last story have been considered on the behavior of models. Regarding this, all analyses were performed by ETABS 9.2.v software (Wilson and Habibullah). Considering (a) drift and rotation of the core over height of buildings, (b) total and warping stress in the core body, (c) shear in beams due to warping stress, (d) effect of closing last story on period of models in various modes, (e) relative displacement between walls in the core system and (f) site effects in far and near field of fault by UBC97 spectra on base shear coefficient showed that the bimoment in open core is negative in the last quarter of building and it is similar to wall-frame structures. Furthermore, analytical results revealed that closed section core in the last story improves behavior of the last quarter of structure height, since closing of core section in the last story does not have significant effect on reducing base shear value in near and far field of active faults.

  14. Demonstrate VERA Core Simulator Performance Improvements L2:PHI.P13.03

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Benjamin S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hamilton, Steven P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jarrett, Michael G. [Univ. of Michigan, Ann Arbor, MI (United States); Kim, Kang Seog [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kochunas, Brendan [Univ. of Michigan, Ann Arbor, MI (United States); Liu, Yuxuan [Univ. of Michigan, Ann Arbor, MI (United States); Palmtag, Scott [Core Physics, Inc., Cary, NC (United States); Salko, Robert K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Stimpson, Shane G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Toth, Alex [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Yee, Ben [Univ. of Michigan, Ann Arbor, MI (United States)

    2016-08-31

    This report describes the performance improvements made to the VERA Core Simulator (VERA-CS) during FY2016. The development of the VERA Core Simulator has focused on the capability needed to deplete physical reactors and help solve various problems; this capability required the accurate simulation of many operating cycles of a nuclear power plant. The first section of this report introduces two test problems used to assess the run-time performance of VERA-CS using a source dated February 2016. The next section provides a brief overview of the major modifications made to decrease the computational cost. Following the descriptions of the major improvements, the run-time for each improvement is shown. Conclusions on the work are presented, and further follow-on performance improvements are suggested.

  15. Improved dating of a mid-fifteenth century volcanic marker in ice cores

    Science.gov (United States)

    Cole-Dai, J.; Ferris, D. G.; McConnell, J. R.; Sigl, M.; Gao, C.

    2013-12-01

    Ice cores are dated with a variety of techniques with varying degrees of accuracy and precision. Recent advances in ice core chemical analysis have enabled high resolution (i.e., sub-annual) measurements that allow many ice cores to be dated with the technique of annual layer counting (ALC). Dating by ALC, when applied to appropriate ice cores, provides accuracy and precision that are not possible with other dating techniques. Two recent ice cores, one from Antarctica and one from Greenland and dated with the ALC technique, yield an 800 year (1200-2007 C.E.) bipolar record of explosive volcanic eruptions. The age uncertainties of volcanic signals in the period of 1400-2007 are no more than ×1 year. A prominent volcanic signal in the 15th century appears in the layers of 1459-1461 of both ice cores, indicating an eruption date of 1458. The mid-15th century eruption of the Kuwae volcano in the tropical Pacific is believed to be the most explosive in the last 700 years and to have impacted global climate. Examination of previous ice core records found 1454-1457 to be the date range of the prominent volcanic signal, presumed to be from the Kuwae eruption, in most Antarctica ice cores. This led to the suggestion that 1452 or 1453 is the probable eruption date for Kuwae. The new bipolar record places 1458×1 as the date of the eruption responsible for the prominent volcanic signal. The date of 1458 appears to be an improvement of the previously suggested date (1452 or 1453) for the eruption responsible for the prominent volcanic signal in the mid-15th century. However, the presence of another, less prominent signal at 1453-1454 in the new bipolar record makes it difficult at this point to attribute either signal to the Kuwae eruption, although current evidence suggests the later (1458) eruption is probably that of Kuwae.

  16. Development of a Multi-dimensional Analysis Methodology for Sodium-water Reaction Phenomena in a SFR Steam Generator

    Energy Technology Data Exchange (ETDEWEB)

    Eoh, Jae Hyuk; Kim, Se Yun; Choi, Byung Seon; Kim, Seong O

    2006-03-15

    A sodium-water reaction (SWR) has been considered as one of the most important issues to be resolved for designing the steam generator and the related systems of a sodium-cooled fast reactor (SFR). In this study, the reasonable SWR analysis at the vicinity of the reaction zone was made by using the appropriate multi-dimensional thermo-hydraulic simulation with detailed chemical reaction model. Based on the investigation results for the capabilities of commercial CFD codes, CFX version 5.7 and its EDM chemical model were selected to simulate the chemically reacting flow with various phases and components. As results of this study, a reasonable methodology for the SWR analysis including detailed information for each phase and the components was provided with the two-dimensional fields of velocity, temperature, mass fraction, etc. In order to investigate the subsequent tube rupture behavior at the reaction zone, the effective method to evaluate the subsequent tube rupture behavior is also proposed by using the relationship between the wastage rate and the eroded tube thickness and is set up by considering allowable stress intensity for the conventional tube material. It is expected that the results of this study will contribute to improve the reliability of a steam generator for GEN-IV SFR in the future.

  17. GAMA/H-ATLAS: a meta-analysis of SFR indicators - comprehensive measures of the SFR-M* relation and cosmic star formation history at z < 0.4

    Science.gov (United States)

    Davies, L. J. M.; Driver, S. P.; Robotham, A. S. G.; Grootes, M. W.; Popescu, C. C.; Tuffs, R. J.; Hopkins, A.; Alpaslan, M.; Andrews, S. K.; Bland-Hawthorn, J.; Bremer, M. N.; Brough, S.; Brown, M. J. I.; Cluver, M. E.; Croom, S.; da Cunha, E.; Dunne, L.; Lara-López, M. A.; Liske, J.; Loveday, J.; Moffett, A. J.; Owers, M.; Phillipps, S.; Sansom, A. E.; Taylor, E. N.; Michalowski, M. J.; Ibar, E.; Smith, M.; Bourne, N.

    2016-09-01

    We present a meta-analysis of star formation rate (SFR) indicators in the Galaxy And Mass Assembly (GAMA) survey, producing 12 different SFR metrics and determining the SFR-M* relation for each. We compare and contrast published methods to extract the SFR from each indicator, using a well-defined local sample of morphologically selected spiral galaxies, which excludes sources which potentially have large recent changes to their SFR. The different methods are found to yield SFR-M* relations with inconsistent slopes and normalizations, suggesting differences between calibration methods. The recovered SFR-M* relations also have a large range in scatter which, as SFRs of the targets may be considered constant over the different time-scales, suggests differences in the accuracy by which methods correct for attenuation in individual targets. We then recalibrate all SFR indicators to provide new, robust and consistent luminosity-to-SFR calibrations, finding that the most consistent slopes and normalizations of the SFR-M* relations are obtained when recalibrated using the radiation transfer method of Popescu et al. These new calibrations can be used to directly compare SFRs across different observations, epochs and galaxy populations. We then apply our calibrations to the GAMA II equatorial data set and explore the evolution of star formation in the local Universe. We determine the evolution of the normalization to the SFR-M* relation from 0 < z < 0.35 - finding consistent trends with previous estimates at 0.3 < z < 1.2. We then provide the definitive z < 0.35 cosmic star formation history, SFR-M* relation and its evolution over the last 3 billion years.

  18. CFC+: Improved dynamics and gravitational waveforms from relativistic core collapse simulations

    CERN Document Server

    Cerdá-Durán, P; Dimmelmeier, H; Font, J A; Ibáñez, J M; Müller, E; Schäfer, G

    2004-01-01

    Core collapse supernovae are a promising source of detectable gravitational waves. Most of the existing (multidimensional) numerical simulations of core collapse in general relativity have been done using approximations of the Einstein field equations. As recently shown by Dimmelmeier et al (2002a,b), one of the most interesting such approximation is the so-called conformal flatness condition (CFC) of Isenberg, Wilson and Mathews. Building on this previous work we present here new results from numerical simulations of relativistic rotational core collapse in axisymmetry, aiming at improving the dynamics and the gravitational waveforms. The computer code used for these simulations evolves the coupled system of metric and fluid equations using the 3+1 formalism, specialized to a new framework for the gravitational field equations which we call CFC+. In this approach we add new degrees of freedom to the original CFC equations, which extend them by terms of second post-Newtonian order. The corrections for CFC+ ar...

  19. An improved continuous flow analysis system for high-resolution field measurements on ice cores.

    Science.gov (United States)

    Kaufmann, Patrik R; Federer, Urs; Hutterli, Manuel A; Bigler, Matthias; Schüpbach, Simon; Ruth, Urs; Schmitt, Jochen; Stocker, Thomas F

    2008-11-01

    Continuous flow analysis (CFA) is a well-established method to obtain information about impurity contents in ice cores as indicators of past changes in the climate system. A section of an ice core is continuously melted on a melter head supplying a sample water flow which is analyzed online. This provides high depth and time resolution of the ice core records and very efficient sample decontamination as only the inner part of the ice sample is analyzed. Here we present an improved CFA system which has been totally redesigned in view of a significantly enhanced overall efficiency and flexibility, signal quality, compactness, and ease of use. These are critical requirements especially for operations of CFA during field campaigns, e.g., in Antarctica or Greenland. Furthermore, a novel deviceto measure the total air content in the ice was developed. Subsequently, the air bubbles are now extracted continuously from the sample water flow for subsequent gas measurements.

  20. Construction of in-situ creep strain test facility for the SFR fuel cladding

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang Gyu; Heo, Hyeong Min; Kim, Jun Hwan; Kim, Sung Ho [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    In this study, in-situ laser inspection creep test machine was developed for the measuring the creep strain of SFR fuel cladding materials. Ferritic-martensitic steels are being considered as an attractive candidate material for a fuel cladding of a SFR due to their low expansion coefficients, high thermal conductivities and excellent irradiation resistances to a void swelling. HT9 steel (12CrMoVW) is initially developed as a material for power plants in Europe in the 1960. This steel has experienced to expose up to 200dpa in FFTE and EBR-II. Ferritic-Martensitic steel's maximum creep strength in existence is 180Mpa for 106 hour 600 .deg., but HT9 steel is 60Mpa. Because SFR is difficult to secure in developing and applying materials, HT9 steel has accumulated validated data and is suitable for SFR component. And also, because of its superior dimensional stability against fast neutron irradiation, Ferritic-martensitic steel of 9Cr and 12Cr steels, such as HT9 and FC92(12Cr-2W) are preferable to utilize in the fuel cladding of an SFR in KAERI. The pressurized thermal creep test of HT9 and FC92 claddings are being conducted in KAERI, but the change of creep strain in cladding is not easy to measure during the creep test due to its pressurized and closed conditions. In this paper, in-situ laser inspection pressurized creep test machine developed for SFR fuel cladding specimens is described. Moreover, the creep strain rate of HT9 at 650 .deg. C was examined from the in-situ laser inspection pressurized creep test machine.

  1. Evaluating core technology capacity based on an improved catastrophe progression method: the case of automotive industry

    Science.gov (United States)

    Zhao, Shijia; Liu, Zongwei; Wang, Yue; Zhao, Fuquan

    2017-01-01

    Subjectivity usually causes large fluctuations in evaluation results. Many scholars attempt to establish new mathematical methods to make evaluation results consistent with actual objective situations. An improved catastrophe progression method (ICPM) is constructed to overcome the defects of the original method. The improved method combines the merits of the principal component analysis' information coherence and the catastrophe progression method's none index weight and has the advantage of highly objective comprehensive evaluation. Through the systematic analysis of the influencing factors of the automotive industry's core technology capacity, the comprehensive evaluation model is established according to the different roles that different indices play in evaluating the overall goal with a hierarchical structure. Moreover, ICPM is developed for evaluating the automotive industry's core technology capacity for the typical seven countries in the world, which demonstrates the effectiveness of the method.

  2. Optimization of a heterogeneous fast breeder reactor core with improved behavior during unprotected transients

    Energy Technology Data Exchange (ETDEWEB)

    Poumerouly, S.; Schmitt, D.; Massara, S.; Maliverney, B. [EDF R and D, 1 avenue du general de Gaulle, 92140 Clamart (France)

    2012-07-01

    Innovative Sodium-cooled Fast Reactors (SFRs) are currently being investigated by CEA, AREVA and EDF in the framework of a joint French collaboration, and the construction of a GEN IV prototype, ASTRID (Advanced Sodium Technical Reactor for Industrial Demonstration), is scheduled in the years 2020. Significant improvements are expected so as to improve the reactor safety: the goal is to achieve a robust safety demonstration of the mastering of the consequences of a Core Disruptive Accident (CDA), whether by means of prevention or mitigation features. In this framework, an innovative design was proposed by CEA in 2010. It aims at strongly reducing the sodium void effect, thereby improving the core behavior during unprotected loss of coolant transients. This design is strongly heterogeneous and includes, amongst others, a fertile plate, a sodium plenum associated with a B{sub 4}C upper blanket and a stepwise modulation of the fissile height of the core (onwards referred to as the 'diabolo shape'). In this paper, studies which were entirely carried out at EDF are presented: the full potential of this heterogeneous concept is thoroughly investigated using the SDDS methodology. (authors)

  3. Improved methodologies for continuous-flow analysis of stable water isotopes in ice cores

    Science.gov (United States)

    Jones, Tyler R.; White, James W. C.; Steig, Eric J.; Vaughn, Bruce H.; Morris, Valerie; Gkinis, Vasileios; Markle, Bradley R.; Schoenemann, Spruce W.

    2017-02-01

    Water isotopes in ice cores are used as a climate proxy for local temperature and regional atmospheric circulation as well as evaporative conditions in moisture source regions. Traditional measurements of water isotopes have been achieved using magnetic sector isotope ratio mass spectrometry (IRMS). However, a number of recent studies have shown that laser absorption spectrometry (LAS) performs as well or better than IRMS. The new LAS technology has been combined with continuous-flow analysis (CFA) to improve data density and sample throughput in numerous prior ice coring projects. Here, we present a comparable semi-automated LAS-CFA system for measuring high-resolution water isotopes of ice cores. We outline new methods for partitioning both system precision and mixing length into liquid and vapor components - useful measures for defining and improving the overall performance of the system. Critically, these methods take into account the uncertainty of depth registration that is not present in IRMS nor fully accounted for in other CFA studies. These analyses are achieved using samples from a South Pole firn core, a Greenland ice core, and the West Antarctic Ice Sheet (WAIS) Divide ice core. The measurement system utilizes a 16-position carousel contained in a freezer to consecutively deliver ˜ 1 m × 1.3 cm2 ice sticks to a temperature-controlled melt head, where the ice is converted to a continuous liquid stream and eventually vaporized using a concentric nebulizer for isotopic analysis. An integrated delivery system for water isotope standards is used for calibration to the Vienna Standard Mean Ocean Water (VSMOW) scale, and depth registration is achieved using a precise overhead laser distance device with an uncertainty of ±0.2 mm. As an added check on the system, we perform inter-lab LAS comparisons using WAIS Divide ice samples, a corroboratory step not taken in prior CFA studies. The overall results are important for substantiating data obtained from LAS

  4. Intensive unilateral core training improves trunk stability without preference for trunk left or right rotation.

    Science.gov (United States)

    Kim, Yushin; Kim, Jungjin; Yoon, BumChul

    2015-01-01

    It is possible to increase multi-directional trunk stability using co-activation. However, it is unclear whether there is a preference for left or right trunk rotation after intensive unilateral stability training. The aim of this study was to examine the directional preference in trunk rotational stability after unilateral core training. This study was conducted on 16 female basketball players. For eight weeks, eight participants performed unilateral core training that focused on one side of the trunk. The remaining eight participants were not provided any additional training. To determine rotational trunk stability, all participants were requested to maintain an upright sitting posture against sudden, external, left or right rotational perturbations of the trunk. Angular displacement of the trunk was measured using a motion analyzer. At the end of the training period, the angular displacement in response to the perturbation was reduced for both rotational directions (left: −26%, right: −24%) in the trained group (p stability improved without particular directional preference in response to unilateral core training. This result adds to our understanding of the nature of trunk stability and multi-directional improvement. Intervention study, Level 1b.

  5. Thermal-hydraulics/thermal-mechanics temporal coupling for unprotected loss of flow accidents simulations on a SFR

    Directory of Open Access Journals (Sweden)

    Patricot Cyril

    2016-01-01

    Full Text Available In the frame of ASTRID designing, unprotected loss of flow (ULOF accidents are considered. As the reactor is not scrammed, power evolution is driven by neutronic feedbacks, among which Doppler effect, linked to fuel temperature, is prominent. Fuel temperature is calculated using thermal properties of fuel pins (we will focus on heat transfer coefficient between fuel pellet and cladding, Hgap, and on fuel thermal conductivity, λfuel which vary with irradiation conditions (neutronic flux, mass flow and history for instance and during transient (mainly because of dilatation of materials with temperature. In this paper, we propose an analysis of the impact of spatial variation and temporal evolution of thermal properties of fuel pins on a CFV-like core [M.S. Chenaud et al., Status of the ASTRID core at the end of the pre-conceptual design phase 1, in Proceedings of ICAPP 2013, Jeju Island, Korea (2013] behavior during an ULOF accident. These effects are usually neglected under some a priori conservative assumptions. The vocation of our work is not to provide a best-estimate calculation of ULOF transient, but to discuss some of its physical aspects. To achieve this goal, we used TETAR, a thermal-hydraulics system code developed by our team to calculate ULOF transients, GERMINAL V1.5, a CEA code dedicated to SFR pin thermal-mechanics calculations and APOLLO3®, a neutronic code in development at CEA.

  6. Summary of Research on Interactive Safety Analysis Program of Pool Type SFR

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The aim of the project was to develop an interactive safety analysis program of pool type sodium cooled fast reactors (SFR), based on a French system code OASIS. The function and physical model of the program should be verified by the application on CEFR design.

  7. Improved performances of polymer-based dielectric by using inorganic/organic core-shell nanoparticles

    Science.gov (United States)

    Benhadjala, W.; Bord-Majek, I.; Béchou, L.; Suhir, E.; Buet, M.; Rougé, F.; Gaud, V.; Plano, B.; Ousten, Y.

    2012-10-01

    BaTiO3/hyperbranched polyester/methacrylate core-shell nanoparticles were studied by varying the shell thickness and the methacrylate ratio. We demonstrated that coalescence typically observed in traditional composites employing polymer matrices is significantly reduced. By modifying the shell thickness, the equivalent filler fraction was tuned from 7 wt. % to 41 wt. %. Obtained permittivities were compared with reported models for two-phase mixtures. The nonlinear behavior of the dielectric constant as a function of the equivalent filler fraction has been fitted with the Bruggeman equation. Methacrylate groups reduce by a decade the loss factor by improving nanoparticles adhesion. The permittivity reaching 85 at 1 kHz makes core-shell nanoparticles a promising material for embedded capacitors.

  8. Spatially-resolved SFR in nearby disk galaxies using IFS data

    Science.gov (United States)

    Catalán-Torrecilla, C.; Gil de Paz, A.; Castillo-Morales, A.; Méndez-Abreu, J.; Pascual, S.; Ruiz-Lara, T.; de Lorenzo-Cáceres, A.; Sánchez-Menguiano, L.

    2017-03-01

    Exploring the spatial distribution of the star formation rate (SFR) in nearby galaxies is essential to understand their evolution through cosmic time. With this aim in mind, we use a representative sample that contains a variety of morphological types, the CALIFA Integral Field Spectroscopy (IFS) sample. Previous to this work, we have verified that our extinction-corrected Hα measurements successfully reproduce the values derived from other SFR tracers such as Hα obs + IR or UV obs + IR (Catalán-Torrecilla et al. 2015). Now, we go one step further applying 2-dimensional photometric decompositions (Méndez-Abreu et al. (2008), Méndez-Abreu et al. (2014)) over these datacubes. This method allows us to obtain the amount of SFR in the central part (bulge or nuclear source), the bar and the disk, separately. First, we determine the light coming from each component as the ratio between the luminosity in every component (bulge, bar or disk) and the total luminosity of the galaxy. Then, for each galaxy we multiply the IFS datacubes by these previous factors to recover the luminosity in each component. Finally, we derive the spectrum associated to each galaxy component integrating the spatial information in the weighted datacube using an elliptical aperture covering the whole galaxy. 2D photometric decomposition applied over 3D datacubes will give us a more detailed understanding of the role that disks play in more massive galaxies. Knowing if the disks in more massive SF galaxies have on average a lower or higher level of star formation activity and how these results are affected by the presence of nuclear bars are still open questions that we can now solve. We describe the behavior of these components in the SFR vs. stellar mass diagram. In particular, we highlight the role of the disks and their contribution to both the integrated SFR for the whole galaxy and the SFR in the disk at different stellar masses in the SFR vs. stellar mass diagram together with their

  9. Data for calibration and validation of numerical models at SFR Nuclear Waste Repository

    Energy Technology Data Exchange (ETDEWEB)

    Axelsson, Carl-Lennart [Golder Associates AB (Sweden)

    1997-12-01

    The final repository for low and intermediate radioactive waste, SFR, is located below the Baltic, offshore of the nuclear power plant at Forsmark. The current operating permit for SKB stipulates that the safety assessment is updated at least every ten year. In response, SKB has started the SAFE project which aims at submitting a complete revised safety analysis before or during the year 2000. The current report is part of the far-field analyses in SAFE and provides information that can be used in a revised hydrogeological modelling of the facility. Information have been collected mainly during the construction phase of SFR, 1983 - 88, and the operation phase from 1988. The specific information that is available for the construction phase is: pressure responses in different bore holes when pumping in one bore hole, groundwater pressure in sections of bore holes, inflow to different parts of the SFR, and groundwater chemistry and isotope analyses in sections of bore holes. During the operation phase, the following information is available: ground-water pressure in sections of bore holes, inflow to different parts of the SFR facility, and groundwater chemistry and isotope analyses in sections of bore holes. The important issues in the groundwater modelling for the performance assessment study of SFR is the amount of water that flows through the storage caverns and the silo together with the possible retention and adsorption in the rock mass, i.e. the flow paths from the repository parts. Thus, the most important type of information is the inflow measurements made in different parts of SFR. The groundwater chemistry may be used to understand the flow pattern and mixing of water with various origin such as fresh groundwater, saline rock/fracture groundwater and Baltic Sea water, especially to predict breakthrough time for the Baltic Sea water at different bore hole sections in fracture zones. The report discusses especially the availability and evolution of inflow and

  10. Site investigation SFR. Fracture mineralogy and geochemistry of borehole sections sampled for groundwater chemistry and Eh. Results from boreholes KFR01, KFR08, KFR10, KFR19, KFR7A and KFR105

    Energy Technology Data Exchange (ETDEWEB)

    Sandstroem, Bjoern (WSP Sverige AB (Sweden)); Tullborg, Eva-Lena (Terralogica AB, Grabo (Sweden))

    2011-01-15

    This report is part of the complementary site investigations for the future expansion of SFR. The report presents the results obtained during a detailed mineralogical and geochemical study of fracture minerals in drill cores from borehole section sampled for groundwater chemistry and where downhole Eh measurements have been performed. The groundwater redox system comprises not only the water, but also the bedrock/fracture mineral system in contact with this water. It is thus important to gain knowledge of the solid phases in contact with the groundwater, i.e. the fracture minerals. The samples studied for mineralogy and geochemistry, here reported, were selected to represent the fracture surfaces in contact with the groundwater in the sampled borehole sections and will give input to the hydrogeochemical model (SFR SDM). The mineralogy was determined using SEM-EDS and XRD and the geochemistry of fracture filling material was analysed by ICP-AES and ICP-QMS. The most common fracture minerals in the samples are mixed layer clay (smectite-illite), illite, chlorite, calcite, quartz, adularia and albite. Other minerals identified in the borehole sections include laumontite, pyrite, barite, chalcopyrite, hematite, Fe-oxyhydroxide, muscovite, REE-carbonate, allanite, biotite, asphaltite, galena, sphalerite, arsenopyrite, uranium phosphate, uranium silicate, Y-Ca silicate, monazite, xenotime, harmotome and fluorite. There are no major differences between the fracture mineralogy of the investigated borehole sections from SFR and the fracture mineralogy of the Forsmark site investigation area. The four fracture mineral generations distinguished within the Forsmark site investigation are also found at SFR. However, some differences have been observed: 1) Barite and uranium minerals are more common in the SFR fractures, 2) clay minerals like mixed layer illite-smectite and illite dominates in contrast to Forsmark where corrensite is by far the most common clay mineral and, 3

  11. Low and intermediate level waste in SFR-1. Reference Waste Inventory 2007

    Energy Technology Data Exchange (ETDEWEB)

    Almkvist, Lisa (Vattenfall Power Consultant AB, Stockholm (SE)); Gordon, Anna (Swedish Nuclear Fuel and Waste Management Co., Stockholm (SE))

    2007-11-15

    The objective with this report is to describe all the waste and the waste package that is expected to be deposited in SFR 1 at the time of closure. The report will form the basis for the release calculation in the safety analysis for SFR 1. Three different scenarios are explored in this report; the waste inventory is based on an estimated operational lifetime of the Swedish nuclear power plants of 50 and 60 years and that closure of the SFR 1 repository will take place in 2040 or 2050 respectively. The third scenario is where the repository is full (one part where the activity adds up to 1016 Bq and one part where the repository is considered full regarding volume). In the report, data about geometries, weights, materials, chemicals and radionuclide are given. No chemotoxic material has been identified in the waste. The inventory is estimated using the Prosit-interface which extracts information from the Triumf database. The inventory is based on so called 'waste types' and the waste types' 'reference waste package'. The reference waste package combined with a prognosis of the number of waste packages to be delivered to SFR 1 gives the final waste inventory for SFR 1. All reference waste packages are thoroughly described in the appendices of this report. The reference waste packages are as far as possible based on actual experiences and measurements. The radionuclide inventory is also based on actual measurements. The inventory is based on measurements of 60Co and 137Cs in waste packages and on measurements of 239Pu and 240Pu in reactor water. Other nuclides in the inventory are calculated with correlation factors

  12. Low and intermediate level waste in SFR-1. Reference Waste Inventory 2007

    Energy Technology Data Exchange (ETDEWEB)

    Almkvist, Lisa (Vattenfall Power Consultant AB, Stockholm (SE)); Gordon, Anna (Swedish Nuclear Fuel and Waste Management Co., Stockholm (SE))

    2007-11-15

    The objective with this report is to describe all the waste and the waste package that is expected to be deposited in SFR 1 at the time of closure. The report will form the basis for the release calculation in the safety analysis for SFR 1. Three different scenarios are explored in this report; the waste inventory is based on an estimated operational lifetime of the Swedish nuclear power plants of 50 and 60 years and that closure of the SFR 1 repository will take place in 2040 or 2050 respectively. The third scenario is where the repository is full (one part where the activity adds up to 1016 Bq and one part where the repository is considered full regarding volume). In the report, data about geometries, weights, materials, chemicals and radionuclide are given. No chemotoxic material has been identified in the waste. The inventory is estimated using the Prosit-interface which extracts information from the Triumf database. The inventory is based on so called 'waste types' and the waste types' 'reference waste package'. The reference waste package combined with a prognosis of the number of waste packages to be delivered to SFR 1 gives the final waste inventory for SFR 1. All reference waste packages are thoroughly described in the appendices of this report. The reference waste packages are as far as possible based on actual experiences and measurements. The radionuclide inventory is also based on actual measurements. The inventory is based on measurements of 60Co and 137Cs in waste packages and on measurements of 239Pu and 240Pu in reactor water. Other nuclides in the inventory are calculated with correlation factors

  13. DANCE, BALANCE AND CORE MUSCLE PERFORMANCE MEASURES ARE IMPROVED FOLLOWING A 9-WEEK CORE STABILIZATION TRAINING PROGRAM AMONG COMPETITIVE COLLEGIATE Dancers

    Science.gov (United States)

    Graning, Jessica; McPherson, Sue; Carter, Elizabeth; Edwards, Joshuah; Melcher, Isaac; Burgess, Taylor

    2017-01-01

    Background Dance performance requires not only lower extremity muscle strength and endurance, but also sufficient core stabilization during dynamic dance movements. While previous studies have identified a link between core muscle performance and lower extremity injury risk, what has not been determined is if an extended core stabilization training program will improve specific measures of dance performance. Hypothesis/Purpose This study examined the impact of a nine-week core stabilization program on indices of dance performance, balance measures, and core muscle performance in competitive collegiate dancers. Study Design Within-subject repeated measures design. Methods A convenience sample of 24 female collegiate dance team members (age = 19.7 ± 1.1 years, height = 164.3 ± 5.3 cm, weight 60.3 ± 6.2 kg, BMI = 22.5 ± 3.0) participated. The intervention consisted of a supervised and non-supervised core (trunk musculature) exercise training program designed specifically for dance team participants performed three days/week for nine weeks in addition to routine dance practice. Prior to the program implementation and following initial testing, transversus abdominis (TrA) activation training was completed using the abdominal draw-in maneuver (ADIM) including ultrasound imaging (USI) verification and instructor feedback. Paired t tests were conducted regarding the nine-week core stabilization program on dance performance and balance measures (pirouettes, single leg balance in passe’ releve position, and star excursion balance test [SEBT]) and on tests of muscle performance. A repeated measures (RM) ANOVA examined four TrA instruction conditions of activation: resting baseline, self-selected activation, immediately following ADIM training and four days after completion of the core stabilization training program. Alpha was set at 0.05 for all analysis. Results Statistically significant improvements were seen on single leg balance in passe

  14. DANCE, BALANCE AND CORE MUSCLE PERFORMANCE MEASURES ARE IMPROVED FOLLOWING A 9-WEEK CORE STABILIZATION TRAINING PROGRAM AMONG COMPETITIVE COLLEGIATE Dancers.

    Science.gov (United States)

    Watson, Todd; Graning, Jessica; McPherson, Sue; Carter, Elizabeth; Edwards, Joshuah; Melcher, Isaac; Burgess, Taylor

    2017-02-01

    Dance performance requires not only lower extremity muscle strength and endurance, but also sufficient core stabilization during dynamic dance movements. While previous studies have identified a link between core muscle performance and lower extremity injury risk, what has not been determined is if an extended core stabilization training program will improve specific measures of dance performance. This study examined the impact of a nine-week core stabilization program on indices of dance performance, balance measures, and core muscle performance in competitive collegiate dancers. Within-subject repeated measures design. A convenience sample of 24 female collegiate dance team members (age = 19.7 ± 1.1 years, height = 164.3 ± 5.3 cm, weight 60.3 ± 6.2 kg, BMI = 22.5 ± 3.0) participated. The intervention consisted of a supervised and non-supervised core (trunk musculature) exercise training program designed specifically for dance team participants performed three days/week for nine weeks in addition to routine dance practice. Prior to the program implementation and following initial testing, transversus abdominis (TrA) activation training was completed using the abdominal draw-in maneuver (ADIM) including ultrasound imaging (USI) verification and instructor feedback. Paired t tests were conducted regarding the nine-week core stabilization program on dance performance and balance measures (pirouettes, single leg balance in passe' releve position, and star excursion balance test [SEBT]) and on tests of muscle performance. A repeated measures (RM) ANOVA examined four TrA instruction conditions of activation: resting baseline, self-selected activation, immediately following ADIM training and four days after completion of the core stabilization training program. Alpha was set at 0.05 for all analysis. Statistically significant improvements were seen on single leg balance in passe' releve and bilateral anterior reach for the SEBT (both p ≤ 0

  15. Conceptual Design on Primary Control Rod Drive Mechanism of a Prototype Gen-IV SFR

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Han; Koo, Gyeong Hoi [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    This paper describes the key concept of the drive mechanism, and suggests a required motor power and reducer gears to meet the functional design requirements, and a seismic response analysis of CRDM housing is performed to check its structural integrity. An AC servo motor is selected as a CRA driving power because it uses permanent magnets and is brushless type while DC motor needs a brush and a coil rotates. The control shim motor size is constrained by a housing diameter of 250mm. The driving system has several design requirements. To calculate the motor power, the drive shaft torque is needed. One part of the drive shaft has a lead screw, driving by a ball-nut. The ball screw driver torque (Tr) is calculated by some equations as follow; A servo motor with a nominal power of 100W, a nominal torque of 0.32 N-m (max. 0.48N-m) is selected considering a safety margin. Its diameter is about 50mm. The fast drive-in motor needs a strong power to insert enforcedly the stuck CRA into core within a required time. The motor sizes are calculated by the same procedure. The diameters are in the range of 80mm to 110mm by the insertion time (10 ∼ 24 seconds). The prototype Gen-IV SFR (sodium-cooled Fast Reactor) is of 150MWe capacity. The reactor has six primary control rod assemblies(CRAs). The primary control rod is used for power control, burn-up compensation and reactor shutdown in response to demands from the plant control or protection systems. The control rod drive mechanism (CRDM) consists of the drive motor assembly, the driveline, and its housing. The driveline consists of three concentric members of a drive shaft, a tension tube, and a position indicator rod, and it connects the drive motor assembly to the CRA. Main issue is that these many driving parts shall be enclosed within a limited housing diameter because the available pitch of CRDMs is limited by 300mm.

  16. Six weeks of core stability training improves landing kinetics among female capoeira athletes: a pilot study.

    Science.gov (United States)

    Araujo, Simone; Cohen, Daniel; Hayes, Lawrence

    2015-03-29

    Core stability training (CST) has increased in popularity among athletes and the general fitness population despite limited evidence CST programmes alone lead to improved athletic performance. In female athletes, neuromuscular training combining balance training and trunk and hip/pelvis dominant CST is suggested to reduce injury risk, and specifically peak vertical ground reaction forces (vGRF) in a drop jump landing task. However, the isolated effect of trunk dominant core stability training on vGRF during landing in female athletes had not been evaluated. Therefore, the objective of this study was to evaluate landing kinetics during a drop jump test following a CST intervention in female capoeira athletes. After giving their informed written consent, sixteen female capoeira athletes (mean ± SD age, stature, and body mass of 27.3 ± 3.7 years, 165.0 ± 4.0 cm, and 59.7 ± 6.3 kg, respectively) volunteered to participate in the training program which consisted of static and dynamic CST sessions, three times per week for six weeks. The repeated measures T-test revealed participants significantly reduced relative vGRF from pre- to post-intervention for the first (3.40 ± 0.78 vs. 2.85 ± 0.52 N·NBW-1, respectively [pcore stability training improves landing kinetics without improving jump height, and may reduce lower extremity injury risk in female athletes.

  17. Improving access to information – defining core electronic resources for research and wellbeing

    Directory of Open Access Journals (Sweden)

    Kristiina Hormia-Poutanen

    2007-11-01

    Full Text Available Research and innovation are listed as the key success factors for the future development of Finnish prosperity and the Finnish economy. The Finnish libraries have developed a scenario to support this vision. University, polytechnic and research institute libraries as well as public libraries have defined the core electronic resources necessary to improve access to information in Finland. The primary aim of this work has been to provide information and justification for central funding for electronic resources to support the national goals. The secondary aim is to help with the reallocation of existing central funds to better support access to information.

  18. Evolution of near-field physico-chemical characteristics of the SFR repository

    Energy Technology Data Exchange (ETDEWEB)

    Savage, D. [Quintessa Ltd., Nottingham (United Kingdom); Stenhouse, M. [Monitor Scientific LLC, Denver, CO (United States); Benbow, S. [Quintessa Ltd., Henley-on-Thames (United Kingdom)

    2000-08-01

    The evaluation of the post-closure performance of the SFR repository needs to consider time dependent evolution of the repository environment. Time-dependent reaction of near-field barriers (cement, steel, bentonite) with saturating groundwater will lead to the development of hyper alkaline repository pore fluids, chemically reducing conditions, and ultimately, the generation of gas through anaerobic corrosion of metals. Cement and concrete will act as chemical conditioning agents to minimise metal corrosion and ultimately, maximise radioelement sorption. The chemical and physical evolution of cement and concrete through reaction with ambient groundwater will thus affect sorption processes through changes in pH, complexing ligands, and solid surface properties. It is desirable that these changes be incorporated into the safety assessment. The sorption behaviour of radionuclides in cementitious systems has been reviewed in detail. The available evidence from experimental work carried out on the influence of organic materials on the sorption behaviour of radionuclides, indicates that most organic degradation products will not affect sorption significantly at the concentrations expected in a cementitious repository. The notable exception to this conclusion involves the degradation products of cellulose and, in particular, polycarboxylic acids represented by iso-saccharinic acid (ISA). Results using ISA indicate a significant reduction in sorption of Pu, by several orders of magnitude, for an ISA concentration of about 10{sup -3} M. More recent data indicate that the negative effect is not as great, though still significant. Therefore, some scoping calculations are advisable to determine how realistic an ISA concentration of about 10{sup -3} M would be for the SFR repository and to estimate concentrations of other relevant organic compounds, in particular EDTA, for comparison. Scoping calculations relevant to the longevity of hyper alkaline pore fluid conditions at SFR

  19. Integrating Morbidity and Mortality Core Competencies and Quality Improvement in Otolaryngology.

    Science.gov (United States)

    Laury, Adrienne M; Bowe, Sarah N; Lospinoso, Joshua

    2017-02-01

    To date, an otolaryngology-specific morbidity and mortality (M&M) conference has never been reported or evaluated. To propose a novel otolaryngology-specific M&M format and to assess its success using a validated assessment tool. Preintervention and postintervention cohort study spanning 14 months (September 2014 to November 2015), with 32 faculty, residents, and medical students attending the department of otolaryngology M&M conference, conducted at the the San Antonio Uniformed Services Health Education Consortium. A novel quality assurance conference was implemented in the department of otolaryngology at the San Antonio Uniformed Services Health Education Consortium. This conference incorporates patient safety reports, otolaryngology-specific quality metrics, and individual case presentations. The revised format integrates the Accreditation Council for Graduate Medical Education (ACGME) core competencies and Quality Improvement and Patient Safety (QI/PS) system. This format was evaluated by faculty, residents, and medical students every other month for 14 months to assess changes in attitudes regarding the M&M conference as well as changes in presentation quality. Overall, 13 faculty, 12 residents, and 7 medical students completed 232 evaluations. Summary statistics of both resident and faculty attitudes about the success of the M&M format seem to improve over the 14 months between the prequestionnaires and postquestionnaires. General attitudes for both residents and faculty significantly improved from the pretest to posttest (odds ratio, 0.32 per month; 95% CI, 0.29-0.35). In the pretest period, "established presentation format" was considered the most necessary improvement, whereas in the posttest period this changed to "incorporate more QI." For resident presentations evaluated using the situation, background, assessment, and review/recommendations (SBAR) tool, all evaluations, from all participants, improved over time. The M&M conference is an essential

  20. A CORE approach to progress monitoring and feedback: Enhancing evidence and improving practice.

    Science.gov (United States)

    Barkham, Michael; Mellor-Clark, John; Stiles, William B

    2015-12-01

    This article describes the Clinical Outcomes in Routine Evaluation (CORE) System and reports on its scientific yield and practice impact. First, we describe the suite of CORE measures, including the centerpiece CORE-Outcome Measure (CORE-OM), its short forms, special purpose forms, translations, and psychometric properties, along with the pretreatment CORE Therapy Assessment Form and the CORE End of Therapy Form. Second, we provide an overview of the scientific yield arising from analyses of large CORE data sets collected in routine practice. Third, we describe the use of CORE measures for feedback in practice settings. Finally, we consider future directions for monitoring and feedback in research and practice.

  1. Improvement in dynamic balance and core endurance after a 6-week core-stability-training program in high school track and field athletes.

    Science.gov (United States)

    Sandrey, Michelle A; Mitzel, Jonathan G

    2013-11-01

    Core training specifically for track and field athletes is vague, and it is not clear how it affects dynamic balance and core-endurance measures. To determine the effects of a 6-week core-stabilization-training program for high school track and field athletes on dynamic balance and core endurance. Test-retest. High school in north central West Virginia. Thirteen healthy high school student athletes from 1 track and field team volunteered for the study. Subjects completed pretesting 1 wk before data collection. They completed a 6-wk core-stabilization program designed specifically for track and field athletes. The program consisted of 3 levels with 6 exercises per level and lasted for 30 min each session 3 times per week. Subjects progressed to the next level at 2-wk intervals. After 6 wk, posttesting was conducted The subjects were evaluated using the Star Excursion Balance Test (SEBT) for posteromedial (PM), medial (M), and anteromedial (AM) directions; abdominal-fatigue test (AFT); back-extensor test (BET); and side-bridge test (SBT) for the right and left sides. Posttest results significantly improved for all 3 directions of the SEBT (PM, M, and AM), AFT, BET, right SBT, and left SBT. Effect size was large for all variables except for PM and AM, where a moderate effect was noted. Minimal-detectable-change scores exceeded the error of the measurements for all dependent variables. After the 6-wk core-stabilization-training program, measures of the SEBT, AFT, BET, and SBT improved, thus advocating the use of this core-stabilization-training program for track and field athletes.

  2. 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.

  3. Status of SFR Codes and Methods QA Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Brunett, Acacia J. [Argonne National Lab. (ANL), Argonne, IL (United States); Briggs, Laural L. [Argonne National Lab. (ANL), Argonne, IL (United States); Fanning, Thomas H. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-01-31

    This report details development of the SAS4A/SASSYS-1 SQA Program and describes the initial stages of Program implementation planning. The provisional Program structure, which is largely focused on the establishment of compliant SQA documentation, is outlined in detail, and Program compliance with the appropriate SQA requirements is highlighted. Additional program activities, such as improvements to testing methods and Program surveillance, are also described in this report. Given that the programmatic resources currently granted to development of the SAS4A/SASSYS-1 SQA Program framework are not sufficient to adequately address all SQA requirements (e.g. NQA-1, NUREG/BR-0167, etc.), this report also provides an overview of the gaps that remain the SQA program, and highlights recommendations on a path forward to resolution of these issues. One key finding of this effort is the identification of the need for an SQA program sustainable over multiple years within DOE annual R&D funding constraints.

  4. What drives the M*-SFR relation turning over at high masses? The role of bulges

    CERN Document Server

    Pan, Zhizheng; Lin, Weipeng; Li, Jinrong; Wang, Jing; Fan, Lulu; Kong, Xu

    2015-01-01

    It is unclear whether bulge growth is responsible for the flattening of the star formation main sequence (MS) at the high mass end. To investigate the role of bulges in shaping the MS, we compare the NUV$-r$ color between the central ($r2.0 tend to be redder in the central NUV$-r$ color than those with $n$2.0 rapidly increases with $M_{\\ast}$ at $M_{\\ast}>10^{10.2}M_{\\sun}$, which is consistent with the turning over of the MS at the same transition mass. We conclude that the increasing fraction of low-sSFR dense bulges in $M_{\\ast}>10^{10.2}M_{\\sun}$ galaxies, rather than increasing B/T, is responsible for the flattened slope of the $M_{\\ast}$$-$SFR relation at high masses.

  5. Development of electromagnetic acoustic transducer (EMAT) phased arrays for SFR inspection

    Science.gov (United States)

    Le Bourdais, Florian; Marchand, Benoît

    2014-02-01

    A long-standing problem for Sodium cooled Fast Reactor (SFR) instrumentation is the development of efficient under-sodium visualization systems adapted to the hot and opaque sodium environment. Electromagnetic Acoustic Transducers (EMAT) are potential candidates for a new generation of Ultrasonic Testing (UT) probes well-suited for SFR inspection that can overcome drawbacks of classical piezoelectric probes in sodium environment. Based on the use of new CIVA simulation tools, we have designed and optimized an advanced EMAT probe for under-sodium visualization. This has led to the development of a fully functional L-wave EMAT sensing system composed of 8 elements and a casing withstanding 200° C sodium inspection. Laboratory experiments demonstrated the probe's ability to sweep an ultrasonic beam to an angle of 15 degrees. Testing in a specialized sodium facility has shown that it was possible to obtain pulse-echo signals from a target under several different angles from a fixed position.

  6. OSCAR-Na: A New Code for Simulating Corrosion Product Contamination in SFR

    Science.gov (United States)

    Génin, J.-B.; Brissonneau, L.; Gilardi, T.

    2016-12-01

    A code named OSCAR-Na has been developed to calculate the mass transfer of corrosion products in the primary circuit of sodium fast reactors (SFR). It is based on a solution/precipitation model, including diffusion in the steel (enhanced under irradiation), diffusion through the sodium boundary layer, equilibrium concentration of each element, and velocity of the interface (bulk corrosion or deposition). The code uses a numerical method for solving the diffusion equation in the steel and the complete mass balance in sodium for all elements. Corrosion and deposition rates are mainly determined by the iron equilibrium concentration in sodium and its oxygen-enhanced dissolution rate. All parameters of the model have been assessed from a literature review, but iron solubility had to be adjusted. A simplified primary system description of PHENIX French SFR was able to assess the correct amounts and profiles of contamination on heat exchanger surfaces for the main radionuclides.

  7. Project SFR 1 SAR-08. Update of priority of FEPs from Project SAFE

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, Anna (Swedish Nuclear Fuel and Waste Management Co., Stockholm (SE)); Loefgren, Martin; Lindgren, Maria (Kemakta Konsult AB, Stockholm (SE)) (eds.)

    2008-03-15

    SFR 1 is a repository for final disposal of low and intermediate level radioactive waste produced at Swedish nuclear power plants, as well as at Swedish industrial, research, and medical treatment facilities. The repository obtained operational license in March 1988. The aim of Project SFR 1 SAR-08 is to perform an updated safety analysis, according to requirements in the regulations. A major difference between this and previous safety analyses is that repository safety should be demonstrated for 100,000 years after repository closure. This should be compared with the time frame of the safety assessment in Project SAFE that was 10,000 years. Due to the extended time frame, permafrost and glaciation have to be considered in the reference evolution of Project SFR 1 SAR-08. Other rationales for the update are recent input from the authorities concerning SAFE documents and the SFR 1 repository, as well as new data concerning the SFR 1 inventory. This report describes the outcome of revisiting the qualitative FEP (Features, Events and Processes) analysis carried out within Project SAFE for the SFR 1 repository. Each and every interaction definition, as defined in SAFE, has been examined with the aim at assuring that the SAFE interaction matrices are also applicable for SAR-08. It was found that this is generally the case, but seven new interactions were defined in order to make the interaction matrices more applicable for SAR-08. The priority of all interactions assigned priority 1 and many interactions assigned priority 2 in SAFE have been carefully examined. The examination has been made in the context of the general initial and boundary conditions that should also form the basis for the SAR-08 main scenario and less probable scenarios. In 48 cases, the priority of the interaction needed upgrading, compared to in SAFE. In a majority of these cases, the upgrade is due to the extended time frame of the safety assessment, from 10,000 years in SAFE to 100,000 years in SAR

  8. Improving performance portability for GPU-specific OpenCL kernels on multi-core/many-core CPUs by analysis-based transformations*#

    Institute of Scientific and Technical Information of China (English)

    Mei WEN; Da-fei HUANG; Chang-qing XUN; Dong CHEN

    2015-01-01

    OpenCL is an open heterogeneous programming framework. Although OpenCL programs are func-tionally portable, they do not provide performance portability, so code transformation often plays an irreplaceable role. When adapting GPU-specifi c OpenCL kernels to run on multi-core/many-core CPUs, coarsening the thread granularity is necessary and thus has been extensively used. However, locality concerns exposed in GPU-specifi c OpenCL code are usually inherited without analysis, which may give side-effects on the CPU performance. Typi-cally, the use of OpenCL’s local memory on multi-core/many-core CPUs may lead to an opposite performance effect, because local-memory arrays no longer match well with the hardware and the associated synchronizations are costly. To solve this dilemma, we actively analyze the memory access patterns using array-access descriptors derived from GPU-specifi c kernels, which can thus be adapted for CPUs by (1) removing all the unwanted local-memory arrays together with the obsolete barrier statements and (2) optimizing the coalesced kernel code with vectorization and locality re-exploitation. Moreover, we have developed an automated tool chain that makes this transformation of GPU-specifi c OpenCL kernels into a CPU-friendly form, which is accompanied with a scheduler that forms a new OpenCL runtime. Experiments show that the automated transformation can improve OpenCL kernel performance on a multi-core CPU by an average factor of 3.24. Satisfactory performance improvements are also achieved on Intel’s many-integrated-core coprocessor. The resultant performance on both architectures is better than or comparable with the corresponding OpenMP performance.

  9. Unexpected improvement in core autism spectrum disorder symptoms after long-term treatment with probiotics

    Directory of Open Access Journals (Sweden)

    Enzo Grossi

    2016-08-01

    Full Text Available Objectives: Autism spectrum disorder is a neurodevelopmental condition that typically displays socio-communicative impairment as well as restricted stereotyped interests and activities, in which gastrointestinal disturbances are commonly reported. We report the case of a boy with Autism Spectrum Disorder (ASD diagnosis, severe cognitive disability and celiac disease in which an unexpected improvement of autistic core symptoms was observed after four months of probiotic treatment. Method: The case study refers to a 12 years old boy with ASD and severe cognitive disability attending the Villa Santa Maria Institute in resident care since 2009. Diagnosis of ASDs according to DSM-V criteria was confirmed by ADOS-2 assessment (Autism Diagnostic Observation Schedule. The medication used was VSL#3, a multi-strain mixture of ten probiotics. The treatment lasted 4 weeks followed by a four month follow-up. The rehabilitation program and the diet was maintained stable in the treatment period and in the follow up. ADOS-2 was assessed six times: two times before starting treatment; two times during the treatment and two times after interruption of the treatment. Results: The probiotic treatment reduced the severity of abdominal symptoms as expected but an improvement in Autistic core symptoms was unexpectedly clinically evident already after few weeks from probiotic treatment start. The score of Social Affect domain of ADOS improved changing from 20 to 18 after two months treatment with a further reduction of 1 point in the following two months. The level 17 of severity remained stable in the follow up period. It is well known that ADOS score does not fluctuate spontaneously along time in ASD and is absolutely stable. Conclusions: The appropriate use of probiotics deserves further research, which hopefully will open new avenues in the fight against ASD.

  10. Low and intermediate level waste in SFR-1. Reference waste inventory

    Energy Technology Data Exchange (ETDEWEB)

    Riggare, P.; Johansson, Claes

    2001-06-01

    The objective with this report is to describe all the waste and the waste package that is expected to be deposited in SFR-1 at the time of closure. This report is a part of the SAFE project (Safety Assessment of Final Repository for Radioactive Operational Waste), i.e. the renewed safety assessment of SFR-1. The accounted waste inventory has been used as input to the release calculation that has been performed in the SAFE project. The waste inventory is based on an estimated operational lifetime of the Swedish nuclear power plants of 40 years and that closure of the SFR repository will happen in 2030. In the report, data about geometries, weights, materials, chemicals and radionuclide are given. No chemo toxic material has been identified in the waste. The inventory is based on so called waste types and the waste types reference waste package. The reference waste package combined with a prognosis of the number of waste packages to the year 2030 gives the final waste inventory for SFR-1. All reference waste packages are thoroughly described in the appendices of this report. The reference waste packages are as far as possible based on actual experiences and measurements. The radionuclide inventory is also based on actual measurements. The inventory is based on measurements of {sup 60}Co and {sup 137} Cs in waste packages and on measurements {sup 239}Pu and {sup 240}Pu in reactor water. Other nuclides in the inventory are calculated with correlation factors. In the SAFE project's prerequisites it was said that one realistic and one conservative (pessimistic) inventory should be produced. The conservative one should then be used for the release calculations. In this report one realistic and one conservative radionuclide inventory is presented. The conservative one adds up to 10{sup 16} Bq. Regarding materials there is only one inventory given since it is not certain what is a conservative assumption.

  11. A carbon budget for the aquatic ecosystem above SFR in Oeregrundsgrepen

    Energy Technology Data Exchange (ETDEWEB)

    Kumblad, L [Stockholm Univ. (Sweden). Dept. of Systems Ecology

    1999-07-01

    The potential hazards of radionuclide release to humans and the environment is regularly evaluated in safety assessments of SFR, the final repository for radioactive operational waste. SFR handles, since 1988, low and intermediate level nuclear waste from Swedish nuclear power plants, medical care attendance, industries and research laboratories and is located in the bedrock 50 meters under the seabed of Oeregrundsgrepen in the southern Bothnian Sea. This report presents a description of the aquatic ecosystem and a carbon budget for the area above SFR with the aim to include ecosystem dynamics in the present safety assessment of the repository (SAFE). The carbon budget will support SAFE by facilitating evaluations of transport and fate of radionuclides, primarily {sup 14}C, in case of a release from the repository and describe the ecosystem structure and function. Furthermore, {sup 14}C is the dose-dominant radionuclide in the repository which most likely will follow the general carbon flow in the ecosystem if there should be a release. The carbon budget was based on biomass and flow of carbon between thirteen functional groups (including POC and DOC) in the ecosystem above SFR and the results indicates that the organisms are self-sufficient on carbon and that the area exports carbon corresponding to approximately 50% of the annual primary production. The largest organic carbon pool is DOC (one and a half time larger than the total biomass) and the major functional organism groups are the macrophytes (37% of the total biomass), benthic macrofauna (36%), and the microphytes (11%). The soft bottom and phytobenthic communities seem to have important roles in the ecosystem since these communities comprise the main part of the living carbon in the studied area.

  12. Progress in the development of the neutron flux monitoring system of the French GEN-IV SFR: simulations and experimental validations [ANIMMA--2015-IO-392

    Energy Technology Data Exchange (ETDEWEB)

    Jammes, C.; Filliatre, P.; Izarra, G. de [CEA, DEN, Cadarache, Reactor Studies Department, 13108 Saint-Paul-lez-Durance (France); Elter, Zs. [CEA, DEN, Cadarache, Reactor Studies Department, 13108 Saint-Paul-lez-Durance (France); Chalmers University of Technology, Department of Applied Physics, Division of Nuclear Engineering, SE-412 96 Goeteborg (Sweden); Verma, V. [CEA, DEN, Cadarache, Reactor Studies Department, 13108 Saint-Paul-lez-Durance (France); Uppsala University, Division of Applied Nuclear Physics, Box 516, SE-75120 Uppsala (Sweden); Hamrita, H.; Bakkali, M. [CEA, DRT, LIST, Metrology, Instrumentation and Information Department, Saclay, 91191 Gif-sur-Yvette (France); Chapoutier, N.; Scholer, A.C.; Verrier, D. [AREVA NP, 10 rue Juliette Recamier F-69456 Lyon (France); Hellesen, C.; Jacobsson, S. [Uppsala University, Division of Applied Nuclear Physics, Box 516, SE-75120 Uppsala (Sweden); Pazsit, I. [Chalmers University of Technology, Department of Applied Physics, Division of Nuclear Engineering, SE-412 96 Goeteborg (Sweden); Cantonnet, B.; Nappe, J.C. [PHOTONIS France, Nuclear Instrumentation, 19100 Brive-la-Gaillarde (France); Molinie, P.; Dessante, P.; Hanna, R.; Kirkpatrick, M.; Odic, E. [Supelec, Energy Department, 3 rue Joliot-Curie, 91191 Gif-sur-Yvette (France)

    2015-07-01

    France has a long experience of about 50 years in designing, building and operating sodium-cooled fast reactors (SFR) such as RAPSODIE, PHENIX and SUPER PHENIX. Fast reactors feature the double capability of reducing nuclear waste and saving nuclear energy resources by burning actinides. Since this reactor type is one of those selected by the Generation IV International Forum, the French government asked, in the year 2006, CEA, namely the French Alternative Energies and Atomic Energy Commission, to lead the development of an innovative GEN-IV nuclear- fission power demonstrator. The major objective is to improve the safety and availability of an SFR. The neutron flux monitoring (NFM) system of any reactor must, in any situation, permit both reactivity control and power level monitoring from startup to full power. It also has to monitor possible changes in neutron flux distribution within the core region in order to prevent any local melting accident. The neutron detectors will have to be installed inside the reactor vessel because locations outside the vessel will suffer from severe disadvantages; radially the neutron shield that is also contained in the reactor vessel will cause unacceptable losses in neutron flux; below the core the presence of a core-catcher prevents from inserting neutron guides; and above the core the distance is too large to obtain decent neutron signals outside the vessel. Another important point is to limit the number of detectors placed in the vessel in order to alleviate their installation into the vessel. In this paper, we show that the architecture of the NFM system will rely on high-temperature fission chambers (HTFC) featuring wide-range flux monitoring capability. The definition of such a system is presented and the justifications of technological options are brought with the use of simulation and experimental results. Firstly, neutron-transport calculations allow us to propose two in-vessel regions, namely the above-core and under-core

  13. On the 3D structure of the mass, metallicity, and SFR space for SF galaxies

    CERN Document Server

    Lara-Lopez, Maritza A; Hopkins, Andrew M

    2012-01-01

    We demonstrate that the space formed by the star-formation rate (SFR), gas-phase metallicity (Z), and stellar mass (M), can be reduced to a plane, as first proposed by Lara-Lopez et al. We study three different approaches to find the best representation of this 3D space, using a principal component analysis, a regression fit, and binning of the data. The PCA shows that this 3D space can be adequately represented in only 2 dimensions, i.e., a plane. We find that the plane that minimises the chi^2 for all variables, and hence provides the best representation of the data, corresponds to a regression fit to the stellar mass as a function of SFR and $Z$, M=f(Z,SFR). We find that the distribution resulting from the median values in bins for our data gives the highest chi^2. We also show that the empirical calibrations to the oxygen abundance used to derive the Fundamental Metallicity Relation (Nagao et al.) have important limitations, which contribute to the apparent inconsistencies. The main problem is that these ...

  14. Update of structural models at SFR nuclear waste repository, Forsmark, Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Axelsson, C.L.; Maersk Hansen, L. [Golder Associates AB (Sweden)

    1997-12-01

    The final repository for low and medium-level waste, SFR, is located below the Baltic, off Forsmark. A number off various geo-scientific investigations have been performed and used to design a conceptual model of the fracture system, to be used in hydraulic modeling for a performance assessment study of the SFR facility in 1987. An updated study was reported in 1993. No formal basic revision of the original conceptual model of the fracture system around SFR has so far been made. During review, uncertainties in the model of the fracture system were found. The previous local structure model is reviewed and an alternative model is presented together with evidence for the new interpretation. The model is based on review of geophysical data, geological mapping, corelogs, hydraulic testing, water inflow etc. The fact that two different models can result from the same data represent an interpretation uncertainty which can not be resolved without more data and basic interpretations of such data. Further refinement of the structure model could only be motivated in case the two different models discussed here would lead to significantly different consequences 20 refs, 24 figs, 16 tabs

  15. Six Weeks of Core Stability Training Improves Landing Kinetics Among Female Capoeira Athletes: A Pilot Study

    Science.gov (United States)

    Araujo, Simone; Cohen, Daniel; Hayes, Lawrence

    2015-01-01

    Core stability training (CST) has increased in popularity among athletes and the general fitness population despite limited evidence CST programmes alone lead to improved athletic performance. In female athletes, neuromuscular training combining balance training and trunk and hip/pelvis dominant CST is suggested to reduce injury risk, and specifically peak vertical ground reaction forces (vGRF) in a drop jump landing task. However, the isolated effect of trunk dominant core stability training on vGRF during landing in female athletes had not been evaluated. Therefore, the objective of this study was to evaluate landing kinetics during a drop jump test following a CST intervention in female capoeira athletes. After giving their informed written consent, sixteen female capoeira athletes (mean ± SD age, stature, and body mass of 27.3 ± 3.7 years, 165.0 ± 4.0 cm, and 59.7 ± 6.3 kg, respectively) volunteered to participate in the training program which consisted of static and dynamic CST sessions, three times per week for six weeks. The repeated measures T-test revealed participants significantly reduced relative vGRF from pre- to post-intervention for the first (3.40 ± 0.78 vs. 2.85 ± 0.52 N·NBW-1, respectively [p<0.05, effect size = 0.60]), and second landing phase (5.09 ± 1.17 vs. 3.02 ± 0.41 N·NBW-1, respectively [p<0.001, effect size = 0.87]). The average loading rate was reduced from pre- to post-intervention during the second landing phase (30.96 ± 18.84 vs. 12.06 ± 9.83 N·NBW·s-1, respectively [p<0.01, effect size = 0.68]). The peak loading rate was reduced from pre- to post-intervention during the first (220.26 ± 111.51 vs. 120.27 ± 64.57 N·NBW·s-1 respectively [p<0.01, effect size = 0.64]), and second (99.52 ± 54.98 vs. 44.71 ± 30.34 N·NBW·s-1 respectively [p<0.01, effect size = 0.70]) landing phase. Body weight, average loading rate during the first landing phase, and jump height were not significantly different between week 0 and week 6

  16. Improvement of neutronic calculations on a Masurca core using adaptive mesh refinement capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, D.; Archier, P.; Le Tellier, R.; Suteau, C., E-mail: damien.fournier@cea.fr, E-mail: pascal.archier@cea.fr, E-mail: romain.le-tellier@cea.fr, E-mail: christophe.suteau@cea.fr [CEA, DEN, DER/SPRC/LEPh, Cadarache, Saint Paul-lez-Durance (France)

    2011-07-01

    The simulation of 3D cores with homogenized assemblies in transport theory remains time and memory consuming for production calculations. With a multigroup discretization for the energy variable and a discrete ordinate method for the angle, a system of about 10{sup 4} coupled hyperbolic transport equations has to be solved. For these equations, we intend to optimize the spatial discretization. In the framework of the SNATCH solver used in this study, the spatial problem is dealt with by using a structured hexahedral mesh and applying a Discontinuous Galerkin Finite Element Method (DGFEM). This paper shows the improvements due to the development of Adaptive Mesh Refinement (AMR) methods. As the SNATCH solver uses a hierarchical polynomial basis, p−refinement is possible but also h−refinement thanks to non conforming capabilities. Besides, as the flux spatial behavior is highly dependent on the energy, we propose to adapt differently the spatial discretization according to the energy group. To avoid dealing with too many meshes, some energy groups are joined and share the same mesh. The different energy-dependent AMR strategies are compared to each other but also with the classical approach of a conforming and highly refined spatial mesh. This comparison is carried out on different quantities such as the multiplication factor, the flux or the current. The gain in time and memory is shown for 2D and 3D benchmarks coming from the ZONA2B experimental core configuration of the MASURCA mock-up at CEA Cadarache. (author)

  17. ENVIRONMENTAL DEPENDENCES OF STAR FORMATION RATE (SFR, SPECIFIC STAR FORMATION RATE (SSFR AND STELLAR MASS AT FIXED LUMINOSITY

    Directory of Open Access Journals (Sweden)

    Xin-Fa Deng

    2013-01-01

    Full Text Available Using four volume-limited Main galaxy samples of the Sloan Digital Sky Survey Data Release 8 (SDSS DR8, we have investigated the environmental dependences of the SFR, SSFR and stellar mass at fixed luminosity. At fixed luminosity, we still observe strong environmental dependences of the SFR, SSFR and stellar mass of galaxies: galaxies in the lowest density regime preferentially have a higher SFR or SSFR and lower stellar mass than galaxies in the densest regime. This result suggests that the limitation or fixation of luminosity does not exert substantial influence on the environmental dependences of the SFR, SSFR and stellar mass of galaxies, which further shows that luminosity is not a fundamental parameter in correlations between galaxy properties and the environment.

  18. PGSFR Core Thermal Design Procedure to Evaluate the Safety Margin

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sun Rock; Kim, Sang-Ji [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    The Korea Atomic Energy Research Institute (KAERI) has performed a SFR design with the final goal of constructing a prototype plant by 2028. The main objective of the SFR prototype plant is to verify the TRU metal fuel performance, reactor operation, and transmutation ability of high-level wastes. The core thermal design is to ensure the safe fuel performance during the whole plant operation. Compared to the critical heat flux in typical light water reactors, nuclear fuel damage in SFR subassemblies arises from a creep induced failure. The creep limit is evaluated based on the maximum cladding temperature, power, neutron flux, and uncertainties in the design parameters, as shown in Fig. 1. In this work, the core thermal design procedures are compared to verify the present PGSFR methodology based on the nuclear plant design criteria/guidelines and previous SFR thermal design methods. The PGSFR core thermal design procedure is verified based on the nuclear plant design criteria/guidelines and previous methods in LWRs and SFRs. The present method aims to directly evaluate the fuel cladding failure and to assure more safety margin. The 2 uncertainty is similar to 95% one-side tolerance limit of 1.96 in LWRs. The HCFs, ITDP, and MCM reveal similar uncertainty propagation for cladding midwall temperature for typical SFR conditions. The present HCFs are mainly employed from the CRBR except the fuel-related uncertainty such as an incorrect fuel distribution. Preliminary PGSFR specific HCFs will be developed by the end of 2015.

  19. Improving the performance of heterogeneous multi-core processors by modifying the cache coherence protocol

    Science.gov (United States)

    Fang, Juan; Hao, Xiaoting; Fan, Qingwen; Chang, Zeqing; Song, Shuying

    2017-05-01

    In the Heterogeneous multi-core architecture, CPU and GPU processor are integrated on the same chip, which poses a new challenge to the last-level cache management. In this architecture, the CPU application and the GPU application execute concurrently, accessing the last-level cache. CPU and GPU have different memory access characteristics, so that they have differences in the sensitivity of last-level cache (LLC) capacity. For many CPU applications, a reduced share of the LLC could lead to significant performance degradation. On the contrary, GPU applications can tolerate increase in memory access latency when there is sufficient thread-level parallelism. Taking into account the GPU program memory latency tolerance characteristics, this paper presents a method that let GPU applications can access to memory directly, leaving lots of LLC space for CPU applications, in improving the performance of CPU applications and does not affect the performance of GPU applications. When the CPU application is cache sensitive, and the GPU application is insensitive to the cache, the overall performance of the system is improved significantly.

  20. Evolution of near-field physico-chemical characteristics of the SFR repository

    Energy Technology Data Exchange (ETDEWEB)

    Savage, D. [Quintessa Ltd., Nottingham (United Kingdom); Stenhouse, M. [Monitor Scientific LLC, Denver, CO (United States); Benbow, S. [Quintessa Ltd., Henley-on-Thames (United Kingdom)

    2000-08-01

    The evaluation of the post-closure performance of the SFR repository needs to consider time dependent evolution of the repository environment. Time-dependent reaction of near-field barriers (cement, steel, bentonite) with saturating groundwater will lead to the development of hyper alkaline repository pore fluids, chemically reducing conditions, and ultimately, the generation of gas through anaerobic corrosion of metals. Cement and concrete will act as chemical conditioning agents to minimise metal corrosion and ultimately, maximise radioelement sorption. The chemical and physical evolution of cement and concrete through reaction with ambient groundwater will thus affect sorption processes through changes in pH, complexing ligands, and solid surface properties. It is desirable that these changes be incorporated into the safety assessment. The sorption behaviour of radionuclides in cementitious systems has been reviewed in detail. The available evidence from experimental work carried out on the influence of organic materials on the sorption behaviour of radionuclides, indicates that most organic degradation products will not affect sorption significantly at the concentrations expected in a cementitious repository. The notable exception to this conclusion involves the degradation products of cellulose and, in particular, polycarboxylic acids represented by iso-saccharinic acid (ISA). Results using ISA indicate a significant reduction in sorption of Pu, by several orders of magnitude, for an ISA concentration of about 10{sup -3} M. More recent data indicate that the negative effect is not as great, though still significant. Therefore, some scoping calculations are advisable to determine how realistic an ISA concentration of about 10{sup -3} M would be for the SFR repository and to estimate concentrations of other relevant organic compounds, in particular EDTA, for comparison. Scoping calculations relevant to the longevity of hyper alkaline pore fluid conditions at SFR

  1. Effects of stellar rotation on star formation rates and comparison to core-collapse supernova rates

    CERN Document Server

    Horiuchi, Shunsaku; Bothwell, Matt S; Thompson, Todd A

    2013-01-01

    We investigate star formation rate (SFR) calibrations in light of recent developments in the modeling of stellar rotation. Using new published non-rotating and rotating stellar tracks, we study the integrated properties of synthetic stellar populations and find that the UV to SFR calibration for the rotating stellar population is 30% smaller than for the non-rotating stellar population, and 40% smaller for the Halpha to SFR calibration. These reductions translate to smaller SFR estimates made from observed UV and Halpha luminosities. Using the UV and Halpha fluxes of a sample of ~300 local galaxies, we derive a total (i.e., sky-coverage corrected) SFR within 11 Mpc of 120-170 Msun/yr and 80-130 Msun/yr for the non-rotating and rotating estimators, respectively. Independently, the number of core-collapse supernovae discovered in the same volume requires a total SFR of 270^{+110}_{-80} Msun/yr, suggesting a mild tension with the SFR estimates made with rotating calibrations. More generally, when compared with t...

  2. Antioxidant Treatment Reduces Formation of Structural Cores and Improves Muscle Function in RYR1Y522S/WT Mice

    Directory of Open Access Journals (Sweden)

    Antonio Michelucci

    2017-01-01

    Full Text Available Central core disease (CCD is a congenital myopathy linked to mutations in the ryanodine receptor type 1 (RYR1, the sarcoplasmic reticulum Ca2+ release channel of skeletal muscle. CCD is characterized by formation of amorphous cores within muscle fibers, lacking mitochondrial activity. In skeletal muscle of RYR1Y522S/WT knock-in mice, carrying a human mutation in RYR1 linked to malignant hyperthermia (MH with cores, oxidative stress is elevated and fibers present severe mitochondrial damage and cores. We treated RYR1Y522S/WT mice with N-acetylcysteine (NAC, an antioxidant provided ad libitum in drinking water for either 2 or 6 months. Our results show that 2 months of NAC treatment starting at 2 months of age, when mitochondrial and fiber damage was still minimal, (i reduce formation of unstructured and contracture cores, (ii improve muscle function, and (iii decrease mitochondrial damage. The beneficial effect of NAC treatment is also evident following 6 months of treatment starting at 4 months of age, when structural damage was at an advanced stage. NAC exerts its protective effect likely by lowering oxidative stress, as supported by the reduction of 3-NT and SOD2 levels. This work suggests that NAC administration is beneficial to prevent mitochondrial damage and formation of cores and improve muscle function in RYR1Y522S/WT mice.

  3. Fabrication of U-10wt.%Zr Fuel slug for SFR by Injection Casting

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Hwan; Song, Hoon; Kim, Hyung Tae; Ko, Young Mo; Kim, Ki Hwan; Lee, Chan B. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    The fabrication technology of metal fuel has been developed by various methods such as rolling, swaging, wire drawing, and co-extrusion, but each of these methods had process limitations requiring an additional subsequent process, and needing the fabrication equipment is complex, which is not favorable for remote use. A practical process of metallic fuel fabrication for an SFR needs to be cost efficient, suitable for remote operation, and capable of mass production while reducing the amount of radioactive waste. Injection casting was chosen as the most promising technique, in the early 1950s, and this technique has been applied to fuel slug fabrication for the Experimental Breeder Reactor-II (EBR-II) driver and the Fast Flux Test Facility (FFTF) fuel pins. Because of the simplistic nature of the process and equipment, compared to other processes examined, this process has been successfully used in a remote operation environment for fueling of the EBR-II reactor. In this study, vacuum injection casting suitable for remote operation has been developed to fabricate metallic fuel for an SFR. Vacuum injection casting technique was developed to fabricate metallic fuel for an SFR. The appearance of the fabricated U-10wt.%Zr fuel was generally sound and the internal integrity was found to be satisfactory through gamma-ray radiography. Minimum fuel losses after casting relative to the initial charge amount of U-10wt.%Zr fuel slugs met the proposed goal of less than 0.1% fuel losses during fabrication. Modifications of the current facility system and advanced casting techniques are underway to produce higher quality fuel slugs.

  4. Experimental validation of thermal design of top shield for a pool type SFR

    Energy Technology Data Exchange (ETDEWEB)

    Aithal, Sriramachandra, E-mail: saithal@igcar.gov.in [Reactor Design Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Babu, V. Rajan; Balasubramaniyan, V.; Velusamy, K. [Reactor Design Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Chellapandi, P. [Bharatiya Nabhikiya Vidyut Nigam Limited, Kalpakkam 603102 (India)

    2016-04-15

    Highlights: • Overall thermal design of top shield in a SFR is experimentally verified. • Air jet cooling is effective in ensuring the temperatures limits for top shield. • Convection patterns in narrow annulus are in line with published CFD results. • Wire mesh insulation ensures gradual thermal gradient at top portion of main vessel. • Under loss of cooling scenario, sufficient time is available for corrective action. - Abstract: An Integrated Top Shield Test Facility towards validation of thermal design of top shield for a pool type SFR has been conceived, constructed & commissioned. Detailed experiments were performed in this experimental facility having full-scale features. Steady state temperature distribution within the facility is measured for various heater plate temperatures in addition to simulating different operating states of the reactor. Following are the important observations (i) jet cooling system is effective in regulating the roof slab bottom plate temperature and thermal gradient across roof slab simulating normal operation of reactor, (ii) wire mesh insulation provided in roof slab-main vessel annulus is effective in obtaining gradual thermal gradient along main vessel top portion and inhibiting the setting up of cellular convection within annulus and (iii) cellular convection with four distinct convective cells sets in the annular gap between roof slab and small rotatable plug measuring ∼ϕ4 m in diameter & gap width varying from 16 mm to 30 mm. Repeatability of results is also ensured during all the above tests. The results presented in this paper is expected to provide reference data for validation of thermal hydraulic models in addition to serving as design validation of jet cooling system for pool type SFR.

  5. Development of Preliminary HT9 Cladding Tube for Sodium-cooled Fast Reactor (SFR)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jun Hwan; Baek, Jong Hyuk; Heo, Hyeong Min; Park, Sang Gyu; Kim, Sung Ho; Lee, Chan Bock [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    To achieve manufacturing technology of the fuel cladding tube in order to keep pace with the predetermined schedule in developing SFR fuel, KAERI has launched in developing fuel cladding tube in cooperation with a domestic steelmaking company. After fabricating medium-sized 1.1 ton HT9 ingot, followed by the multiple processes of hot and cold working, preliminary samples of HT9 seamless cladding tube having 7.4mm in outer diameter, 0.56mm in thickness, and 3m in length were fabricated. The objective of this study is to summarize the brief development status of the HT9 cladding tubes. Mechanical properties like axial tension, biaxial burst, pressurized creep and sodium compatibility of the cladding tubes were carried out to set up the performance evaluation technology to test the prototype FMS cladding tube which is going to be manufactured in next stage. As a part of developing fuel cladding for the Sodium-cooled Fast Reactor (SFR), preliminary HT9 cladding tube was fabricated in cooperation with a domestic steelmaking company. Microstructure as well as mechanical tests like axial tensile test, biaxial burst test, and pressurized creep test of the fuel cladding were carried out. Performance of the domestic HT9 tube was revealed to be similar in the previously fabricated foreign HT9 tube. Further prototype FMS cladding tube is going to be manufactured in next year based on this experience. Various test items like mechanical test, sodium compatibility test, microstructural analysis, basic property, cladding performance under transient situation, and performance under ion and neutron irradiation are going be performed in the future to set up the relevant technology for the licensing of the SFR cladding tube.

  6. Cladding defects in hollow core fibers for surface mode suppression and improved birefringence.

    Science.gov (United States)

    Michieletto, M; Lyngsø, J K; Lægsgaard, J; Bang, O

    2014-09-22

    We demonstrate a novel polarization maintaining hollow-core photonic bandgap fiber geometry that reduces the impact of surface modes on fiber transmission. The cladding structure is modified with a row of partially collapsed holes to strip away unwanted surface modes. A theoretical investigation of the surface mode stripping is presented and compared to the measured performance of four 7-cells core fibers that were drawn with different collapse ratio of the defects. The varying pressure along the defect row in the cladding during drawing introduces an ellipticity of the core. This, combined with the presence of antiresonant features on the core wall, makes the fibers birefringent, with excellent polarization maintaining properties.

  7. Methotrexate carried in lipid core nanoparticles reduces myocardial infarction size and improves cardiac function in rats.

    Science.gov (United States)

    Maranhão, Raul C; Guido, Maria C; de Lima, Aline D; Tavares, Elaine R; Marques, Alyne F; Tavares de Melo, Marcelo D; Nicolau, Jose C; Salemi, Vera Mc; Kalil-Filho, Roberto

    2017-01-01

    Acute myocardial infarction (MI) is accompanied by myocardial inflammation, fibrosis, and ventricular remodeling that, when excessive or not properly regulated, may lead to heart failure. Previously, lipid core nanoparticles (LDE) used as carriers of the anti-inflammatory drug methotrexate (MTX) produced an 80-fold increase in the cell uptake of MTX. LDE-MTX treatment reduced vessel inflammation and atheromatous lesions induced in rabbits by cholesterol feeding. The aim of the study was to investigate the effects of LDE-MTX on rats with MI, compared with commercial MTX treatment. Thirty-eight Wistar rats underwent left coronary artery ligation and were treated with LDE-MTX, or with MTX (1 mg/kg intraperitoneally, once/week, starting 24 hours after surgery) or with LDE without drug (MI-controls). A sham-surgery group (n=12) was also included. Echocardiography was performed 24 hours and 6 weeks after surgery. The animals were euthanized and their hearts were analyzed for morphometry, protein expression, and confocal microscopy. LDE-MTX treatment achieved a 40% improvement in left ventricular (LV) systolic function and reduced cardiac dilation and LV mass, as shown by echocardiography. LDE-MTX reduced the infarction size, myocyte hypertrophy and necrosis, number of inflammatory cells, and myocardial fibrosis, as shown by morphometric analysis. LDE-MTX increased antioxidant enzymes; decreased apoptosis, macrophages, reactive oxygen species production; and tissue hypoxia in non-infarcted myocardium. LDE-MTX increased adenosine bioavailability in the LV by increasing adenosine receptors and modulating adenosine catabolic enzymes. LDE-MTX increased the expression of myocardial vascular endothelium growth factor (VEGF) associated with adenosine release; this correlated not only with an increase in angiogenesis, but also with other parameters improved by LDE-MTX, suggesting that VEGF increase played an important role in the beneficial effects of LDE-MTX. Overall effects of

  8. Application of the IGSN for improved data - sample - drill core linkage

    Science.gov (United States)

    Behnken, Andree; Wallrabe-Adams, Hans-Joachim; Röhl, Ursula; Krysiak, Frank

    2016-04-01

    The large number of samples resulting from geoscientific research creates a need for a system that has the ability to allocate unique identifiers for individual samples (cores, core sections, rock samples...). In this abstract we present a solution that utilises the IGSN (1) Registry Metadata Store (2) to automatically register unique IGSN's for samples and submit corresponding metadata. An automated workflow has been set up to register IGSN's and submit metadata for cores stored for example at the IODP (3) Bremen Core Repository (BCR) in Bremen and the BGR National Core Repository for Research Drilling in Berlin, and partly transfer the core information to the GESEP (4) Virtual Core Repository (5). Detailed metadata for these cores are stored in a DIS (6), from which xml files containing all necessary information for IGSN and metadata submission are automatically generated. These files are automatically processed to extract and register the unique IGSN as well as the corresponding metadata. After this parsing process, the IGSN registration and metadata submission processes are triggered by posting the appropriate IGSN API (7) service calls. 1. International Geo Sample Number 2. https://doidb.wdc-terra.org/igsn/ 3. Integrated Ocean Drilling Program / International Ocean Discovery Program 4. German Scientific Earth Probing Consortium 5. http://www.gesep.org/infrastruktur/kernlager/portal/ 6. Drilling Information System 7. https://doidb.wdc-terra.org/igsn/static/apidoc

  9. Improvement of Core Performance by Introduction of Moderators in a Blanket Region of Fast Reactors

    Directory of Open Access Journals (Sweden)

    Toshio Wakabayashi

    2013-01-01

    Full Text Available An application of deuteride moderator for fast reactor cores is proposed for power flattening that can mitigate thermal spikes and alleviate the decrease in breeding ratio, which sometimes occurs when hydrogen moderator is applied as a moderator. Zirconium deuteride is employed in a form of pin arrays at the inner most rows of radial blanket fuel assemblies, which works as a reflector in order to flatten the radial power distribution in the outer core region of MONJU. The power flattening can be utilized to increase core average burn-up by increasing operational time. The core characteristics have been evaluated with a continuous-energy model Monte Carlo code MVP and the JENDL-3.3 cross-section library. The result indicates that the discharged fuel burn-up can be increased by about 7% relative to that of no moderator in the blanket region due to the power flattening when the number of deuteride moderator pins is 61. The core characteristics and core safety such as void reactivity, Doppler coefficient, and reactivity insertion that occurred at dissolution of deuteron were evaluated. It was clear that the serious drawback did not appear from the viewpoints of the core characteristics and core safety.

  10. The SFR-M* Relation and Empirical Star-Formation Histories from ZFOURGE at 0.5 < z < 4

    CERN Document Server

    Tomczak, Adam R; Tran, Kim-Vy H; Labbe, Ivo; Straatman, Caroline M S; Papovich, Casey; Glazebrook, Karl; Allen, Rebecca; Brammer, Gabreil B; Cowley, Michael; Dickinson, Mark; Elbaz, David; Inami, Hanae; Kacprzak, Glenn G; Morrison, Glenn E; Nanayakkara, Themiya; Persson, S Eric; Rees, Glen A; Salmon, Brett; Schreiber, Corentin; Spitler, Lee R; Whitaker, Katherine E

    2015-01-01

    We explore star-formation histories (SFHs) of galaxies based on the evolution of the star-formation rate stellar mass relation (SFR-M*). Using data from the FourStar Galaxy Evolution Survey (ZFOURGE) in combination with far-IR imaging from the Spitzer and Herschel observatories we measure the SFR-M* relation at 0.5 < z < 4. Similar to recent works we find that the average infrared SEDs of galaxies are roughly consistent with a single infrared template across a broad range of redshifts and stellar masses, with evidence for only weak deviations. We find that the SFR-M* relation is not consistent with a single power-law of the form SFR ~ M*^a at any redshift; it has a power-law slope of a~1 at low masses, and becomes shallower above a turnover mass (M_0) that ranges from 10^9.5 - 10^10.8 Msol, with evidence that M_0 increases with redshift. We compare our measurements to results from state-of-the-art cosmological simulations, and find general agreement in the slope of the SFR-M* relation albeit with system...

  11. From Haloes to Galaxies - I: The dynamics of the gas regulator model and the implied cosmic sSFR-history

    CERN Document Server

    Peng, Yingjie

    2014-01-01

    We explore the basic parameters that drive the evolution of the fundamental properties of star forming galaxies within the gas regulator model, or bathtub-model. We derive the general analytic form of the evolution of the key galaxy properties, i.e. gas mass, star formation rate (SFR), stellar mass, specific SFR, gas fraction, gas phase metallicity and stellar metallicity, without assuming that galaxies live in the equilibrium state. We find that the timescale required to reach equilibrium, tau_eq, which is determined by the product of star-formation efficiency and mass-loading factor, is the central parameter in the gas regulator model that is essentially in control of the evolution of all key galaxy properties. The scatters in most of the key scaling relations are primarily governed by tau_eq. Most strikingly, the predicted sSFR evolution is controlled solely by tau_eq (apart from the cosmic time). Although the precise evolution of the sSFR depends on tau_eq, the sSFR history is largely insensitive to diffe...

  12. Effect of the star formation histories on the SFR-M∗ relation at z ≥ 2

    Science.gov (United States)

    Cassarà, L. P.; Maccagni, D.; Garilli, B.; Scodeggio, M.; Thomas, R.; Le Fèvre, O.; Zamorani, G.; Schaerer, D.; Lemaux, B. C.; Cassata, P.; Le Brun, V.; Pentericci, L.; Tasca, L. A. M.; Vanzella, E.; Zucca, E.; Amorín, R.; Bardelli, S.; Castellano, M.; Cimatti, A.; Cucciati, O.; Durkalec, A.; Fontana, A.; Giavalisco, M.; Grazian, A.; Hathi, N. P.; Ilbert, O.; Paltani, S.; Ribeiro, B.; Sommariva, V.; Talia, M.; Tresse, L.; Vergani, D.; Capak, P.; Charlot, S.; Contini, T.; de la Torre, S.; Dunlop, J.; Fotopoulou, S.; Guaita, L.; Koekemoer, A.; López-Sanjuan, C.; Mellier, Y.; Pforr, J.; Salvato, M.; Scoville, N.; Taniguchi, Y.; Wang, P. W.

    2016-08-01

    We investigate the effect of different star formation histories (SFHs) on the relation between stellar mass (M∗) and star formation rate (SFR) using a sample of galaxies with reliable spectroscopic redshift zspec> 2 drawn from the VIMOS Ultra-Deep Survey (VUDS). We produce an extensive database of dusty model galaxies, calculated starting from a new library of single stellar population (SSPs) models, weighted by a set of 28 different star formation histories based on the Schmidt function, and characterized by different ratios of the gas infall timescale τinfall to the star formation efficiency ν. Dust extinction and re-emission were treated by means of the radiative transfer calculation. The spectral energy distribution (SED) fitting technique was performed by using GOSSIP+, a tool able to combine both photometric and spectroscopic information to extract the best value of the physical quantities of interest, and to consider the intergalactic medium (IGM) attenuation as a free parameter. We find that the main contribution to the scatter observed in the SFR-M∗ plane is the possibility of choosing between different families of SFHs in the SED fitting procedure, while the redshift range plays a minor role. The majority of the galaxies, at all cosmic times, are best fit by models with SFHs characterized by a high τinfall/ν ratio. We discuss the reliability of a low percentage of dusty and highly star-forming galaxies in the context of their detection in the far infrared (FIR).

  13. Ionization States of galaxies: Evolution, SFR-M_star-Z Dependence, and Ionizing Photon Escape

    CERN Document Server

    Nakajima, Kimihiko

    2013-01-01

    We present a systematic study for ionization states of galaxies at z=0-3 with ~140,000 SDSS galaxies and 108 intermediate to high redshift galaxies from the literature, using an ionization-parameter sensitive line ratio of [OIII]5007/[OII]3727 and photoionization models. We confirm that z=2-3 galaxies show an [OIII]/[OII] ratio significantly higher than typical local galaxies by a factor of >~10, and the photoionization models reveal that these high-z galaxies have an ionization parameter of log(qion/cm s^{-1})~7.6-9.0, a factor of ~4-10 higher than local galaxies. For galaxies at any redshifts, we identify a correlation between the [OIII]/[OII] ratio and galaxy global properties of star-formation rate (SFR), stellar mass (M_star), and metallicity (Z). We extend the fundamental metallicity relation (FMR; Mannucci et al. 2010; Lara-lopez et al. 2010), and develop the fundamental ionization relation (FIR), a four-dimensional relation of ionization parameter, SFR, M_star, and Z. The intermediate and high-z galax...

  14. Model summary report for the safety assessment SFR 1 SAR-08

    Energy Technology Data Exchange (ETDEWEB)

    2008-03-15

    This document is the model summary report for the safety assessment SFR 1 SAR-08. In the report, the quality assurance measures conducted for the assessment codes are presented together with the chosen methodology. In the safety assessment SFR1 SAR-08, a number of different computer codes are used. In order to better understand how these codes are related an Assessment Model Flowchart, AMF, has been produced within the project. From the AMF, it is possible to identify the different modelling tasks and consequently also the different computer codes used. A number of different computer codes are used in the assessment of which some are commercial while others are developed for assessment projects. QA requirements must on the one hand take this diversity into account and on the other hand be well defined. In the methodology section of the report the following requirements are defined: - It must be demonstrated that the code is suitable for its purpose. - It must be demonstrated that the code has been properly used. - It must be demonstrated that the code development process has followed appropriate procedures and that the code produces accurate results. Although the requirements are identical for all codes, the measures used to show that the requirements are fulfilled will be different for different codes (for instance due to the fact that for some software the source-code is not available for review). Subsequent to the methodology section, each assessment code is presented and it is shown how the requirements are met

  15. Outcrop and core integrative ichnofabric analysis of Miocene sediments from Lepe, Huelva (SW Spain): Improving depositional and paleoenvironmental interpretations

    Science.gov (United States)

    Rodríguez-Tovar, Francisco J.; Dorador, Javier; Mayoral, Eduardo; Santos, Ana

    2017-03-01

    Ichnofabric analysis was conducted in Miocene sediments from Lepe (Huelva, SW Spain) based on integrative outcrop and core research, to improve interpretations of depositional and paleoenvironmental conditions, with special attention to sequence stratigraphy. Seven intervals were differentiated in outcrops based on stratigraphic and ichnological features, consisting of two ichnofabrics: Ophiomorpha-Thalassinoides-Spongeliomorpha ichnofabric characterizes intervals 1, 2, 6, 7 and 8, while Palaeophycus-Planolites-Phycosiphon ichnofabric characterizes intervals 3, 4 and 5. Fourteen ichnofabrics were differentiated in the core, mainly in view of lithological features, including ferruginous material, grain size, mottled background, ichnotaxa, and Bioturbation Index. A comparison between outcrop and core ichnofabrics through the upper 13.5 m, corresponding to the uppermost Tortonian-lowermost Messinian interval, revealed certain similarities as well as some differences. A continuous and relatively slow siliciclastic deposition with punctual variations in the sedimentation rate can be interpreted that, associated with favorable paleoenvironmental parameters such as aerobic conditions and nutrient availability, evidence that a well-developed and diverse macroinvertebrate trace maker community existed at that time. Softgrounds are dominant, but occasionally loosegrounds and even firmgrounds could develop. The ichnofabric distribution shows long-range patterns in outcrop and core, and short-range patterns exclusively in core. Long-range patterns reflect the last phases of a transgressive system tract, with a "maximum flooding zone" at the end, and then a highstand normal regression. High-frequency, short-range, repetitive patterns in ichnofabrics from core, mainly between ichnofabrics 6/8 to 9 from lower to upper part of the pattern, can be linked to "local flooding surfaces", subdividing the "maximum flooding zone" into parasequences. Our results reveals the usefulness of

  16. Improved damage tolerant face/core interface design in sandwich structures

    DEFF Research Database (Denmark)

    Lundsgaard-Larsen, Christian; Berggreen, Christian; Quispitupa, Amilcar

    2009-01-01

    kinking behavior may be altered / avoided by changing the interface design by using Chopped Strand Mat (CSM), Continuous Filament Mat (CFM) and woven mats at the face/core interface as sources for fiber bridging, thus keeping and arresting the crack in the interface.......A face/core debond in a sandwich structure may propagate in the interface or kink into either the face or core depending on the mode-mixity of the loading. This study explores experimental methodologies for mapping the kinking behavior at various mode-mixities. Further, it is shown that the crack...

  17. Cladding defects in hollow core fibers for surface mode suppression and improved birefringence

    DEFF Research Database (Denmark)

    Michieletto, Mattia; Lyngso, J. K.; Lægsgaard, Jesper;

    2014-01-01

    We demonstrate a novel polarization maintaining hollow-core photonic bandgap fiber geometry that reduces the impact of surface modes on fiber transmission. The cladding structure is modified with a row of partially collapsed holes to strip away unwanted surface modes. A theoretical investigation...... of the surface mode stripping is presented and compared to the measured performance of four 7-cells core fibers that were drawn with different collapse ratio of the defects. The varying pressure along the defect row in the cladding during drawing introduces an ellipticity of the core. This, combined...

  18. Genetic characterization of a core set of a tropical maize race Tuxpeno for further use in maize improvement.

    Directory of Open Access Journals (Sweden)

    Weiwei Wen

    Full Text Available The tropical maize race Tuxpeño is a well-known race of Mexican dent germplasm which has greatly contributed to the development of tropical and subtropical maize gene pools. In order to investigate how it could be exploited in future maize improvement, a panel of maize germplasm accessions was assembled and characterized using genome-wide Single Nucleotide Polymorphism (SNP markers. This panel included 321 core accessions of Tuxpeño race from the International Maize and Wheat Improvement Center (CIMMYT germplasm bank collection, 94 CIMMYT maize lines (CMLs and 54 U.S. Germplasm Enhancement of Maize (GEM lines. The panel also included other diverse sources of reference germplasm: 14 U.S. maize landrace accessions, 4 temperate inbred lines from the U.S. and China, and 11 CIMMYT populations (a total of 498 entries with 795 plants. Clustering analyses (CA based on Modified Rogers Distance (MRD clearly partitioned all 498 entries into their corresponding groups. No sub clusters were observed within the Tuxpeño core set. Various breeding strategies for using the Tuxpeño core set, based on grouping of the studied germplasm and genetic distance among them, were discussed. In order to facilitate sampling diversity within the Tuxpeño core, a minicore subset of 64 Tuxpeño accessions (20% of its usual size representing the diversity of the core set was developed, using an approach combining phenotypic and molecular data. Untapped diversity represents further use of the Tuxpeño landrace for maize improvement through the core and/or minicore subset available to the maize community.

  19. Design of the Face/Core Interface for Improved Fracture Resistance

    DEFF Research Database (Denmark)

    Lundsgaard-Larsen, Christian; Berggreen, Christian; Carlsson, Leif A.

    2008-01-01

    This study investigates the face/core fracture behavior of sandwich specimens with different designs. The traditional interface with a quadraxial mat directly adhered to the foam core is compared to interfaces where an additional mat with randomly oriented fibers is inserted between core and face....... The extra mat affects the crack propagation path in the sandwich specimen, and makes it more likely for the crack to propagate at or near the interface, instead of kinking into the laminate or core. Further, the extra mat acts as a source for fiber bridging, and hereby the fracture resistance is increased...... as bridging fibers shield the crack tip from the loading. Results show that the increase in fracture resistance due to fiber bridging is significant. Cohesive laws regarding cracking of sandwich interfaces are extracted....

  20. Influence Factors and Improvement Recommendations for Core Competency of Township Enterprises

    OpenAIRE

    Zhang, Chengjun

    2014-01-01

    Core competency of township enterprises may be influenced from the property right, technology, scale operation, financial management and talent. In view of these influence factors, township enterprises should conduct technological innovation, bring into full play functions of talents, promote corporate culture of township enterprises, attach great importance to development of core products and innovation of relevant systems, and establish market information platform for township enterprises.

  1. Influence Factors and Improvement Recommendations for Core Competency of Township Enterprises

    Institute of Scientific and Technical Information of China (English)

    Chengjun; ZHANG

    2014-01-01

    Core competency of township enterprises may be influenced from the property right,technology,scale operation,financial management and talent. In view of these influence factors,township enterprises should conduct technological innovation,bring into full play functions of talents,promote corporate culture of township enterprises,attach great importance to development of core products and innovation of relevant systems,and establish market information platform for township enterprises.

  2. Core-shell hematite nanorods: a simple method to improve the charge transfer in the photoanode for photoelectrochemical water splitting.

    Science.gov (United States)

    Gurudayal; Chee, Png Mei; Boix, Pablo P; Ge, Hu; Yanan, Fang; Barber, James; Wong, Lydia Helena

    2015-04-01

    We report a simple method to produce a stable and repeatable photoanode for water splitting with a core-shell hematite (α-Fe2O3) nanorods system by combining spray pyrolysis and hydrothermal synthesis. Impedance spectroscopy revealed passivation of the surface states by the shell layer, which results in an increase of the charge injection through the hematite conduction band. In pristine hematite more holes are accumulated on the surface and the charge transfer to the electrolyte occurs through surface states, whereas in the core-shell hematite photoanode the majority of hole transfer process occurs through the valence band. As a result the photoactivity of the core-shell nanorods, 1.2 mA cm(-2), at 1.23 V vs RHE, is twice that of pristine hematite nanorods. The alteration of the interface energetics is supported by TEM, showing that the crystallinity of the surface has been improved by the deposition of the shell.

  3. [Improvement of sensitivity in the second generation HCV core antigen assay by a novel concentration method using polyethylene glycol (PEG)].

    Science.gov (United States)

    Higashimoto, Makiko; Takahashi, Masahiko; Jokyu, Ritsuko; Syundou, Hiromi; Saito, Hidetsugu

    2007-11-01

    A HCV core antigen (Ag) detection assay system, Lumipulse Ortho HCV Ag has been developed and is commercially available in Japan with a lower detection level limit of 50 fmol/l, which is equivalent to 20 KIU/ml in PCR quantitative assay. HCV core Ag assay has an advantage of broader dynamic range compared with PCR assay, however the sensitivity is lower than PCR. We developed a novel HCV core Ag concentration method using polyethylene glycol (PEG), which can improve the sensitivity five times better than the original assay. The reproducibility was examined by consecutive five-time measurement of HCV patients serum, in which the results of HCV core Ag original and concentrated method were 56.8 +/- 8.1 fmol/l (mean +/- SD), CV 14.2% and 322.9 +/- 45.5 fmol/l CV 14.0%, respectively. The assay results of HCV negative samples in original HCV core Ag were all 0.1 fmol/l and the results were same even in the concentration method. The results of concentration method were 5.7 times higher than original assay, which was almost equal to theoretical rate as expected. The assay results of serially diluted samples were also as same as expected data in both original and concentration assay. We confirmed that the sensitivity of HCV core Ag concentration method had almost as same sensitivity as PCR high range assay in the competitive assay study using the serially monitored samples of five HCV patients during interferon therapy. A novel concentration method using PEG in HCV core Ag assay system seems to be useful for assessing and monitoring interferon treatment for HCV.

  4. Synthesis of monodisperse TiO2-paraffin core-shell nanoparticles for improved dielectric properties.

    Science.gov (United States)

    Balasubramanian, Balamurugan; Kraemer, Kristin L; Reding, Nicholas A; Skomski, Ralph; Ducharme, Stephen; Sellmyer, David J

    2010-04-27

    Core-shell structures of oxide nanoparticles having a high dielectric constant, and organic shells with large breakdown field are attractive candidates for large electrical energy storage applications. A high growth temperature, however, is required to obtain the dielectric oxide nanoparticles, which affects the process of core-shell formation and also leads to poor control of size, shape, and size-distribution. In this communication, we report a new synthetic process to grow core-shell nanoparticles by means of an experimental method that can be easily adapted to synthesize core-shell structures from a variety of inorganic-organic or inorganic-inorganic materials. Monodisperse and spherical TiO2 nanoparticles were produced at room temperature as a collimated cluster beam in the gas phase using a cluster-deposition source and subsequently coated with uniform paraffin nanoshells using in situ thermal evaporation, prior to deposition on substrates for further characterization and device processing. The paraffin nanoshells prevent the TiO2 nanoparticles from contacting each other and also act as a matrix in which the volume fraction of TiO2 nanoparticles was varied by controlling the thickness of the nanoshells. Parallel-plate capacitors were fabricated using dielectric core-shell nanoparticles having different shell thicknesses. With respect to the bulk paraffin, the effective dielectric constant of TiO2-paraffin core-shell nanoparticles is greatly enhanced with a decrease in the shell thickness. The capacitors show a minimum dielectric dispersion and low dielectric losses in the frequency range of 100 Hz-1 MHz, which are highly desirable for exploiting these core-shell nanoparticles for potential applications.

  5. In vitro hyperthermia with improved colloidal stability and enhanced SAR of magnetic core/shell nanostructures.

    Science.gov (United States)

    Patil, R M; Thorat, N D; Shete, P B; Otari, S V; Tiwale, B M; Pawar, S H

    2016-02-01

    Magnetic core/shell nanostructures of Fe3O4 nanoparticles coated with oleic acid and betaine-HCl were studied for their possible use in magnetic fluid hyperthermia (MFH). Their colloidal stability and heat induction ability were studied in different media viz. phosphate buffer solution (PBS), saline solution and glucose solution with different physiological conditions and in human serum. The results showed enhanced colloidal stability in these media owing to their high zeta potential values. Heat induction studies showed that specific absorption rates (SAR) of core/shells were 82-94W/g at different pH of PBS and concentrations of NaCl and glucose. Interestingly, core/shells showed 78.45±3.90W/g SAR in human serum. The cytotoxicity of core/shells done on L929 and HeLa cell lines using 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide and trypan blue dye exclusion assays showed >89% and >80% cell viability for 24 and 48h respectively. Core/shell structures were also found to be very efficient for in vitro MFH on cancer cell line. About 95% cell death was occurred in 90min after hyperthermia treatment. The mechanism of cell death was found to be elevated ROS generation in cells after exposure to core/shells in external magnetic field. This study showed that these core/shells have a great potential to be used in in vivo MFH. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Complete Au@ZnO core-shell nanoparticles with enhanced plasmonic absorption enabling significantly improved photocatalysis.

    Science.gov (United States)

    Sun, Yiqiang; Sun, Yugang; Zhang, Tao; Chen, Guozhu; Zhang, Fengshou; Liu, Dilong; Cai, Weiping; Li, Yue; Yang, Xianfeng; Li, Cuncheng

    2016-05-19

    Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic absorption in the visible range due to the Au NP cores. They also show a significantly improved photocatalytic performance in comparison with their single-component counterparts, i.e., the Au NPs and ZnO NPs. Moreover, the high catalytic activity of the as-synthesized Au@ZnO core-shell NPs can be maintained even after many cycles of photocatalytic reaction. Our results shed light on the fact that the Au@ZnO core-shell NPs represent a promising class of candidates for applications in plasmonics, surface-enhanced spectroscopy, light harvest devices, solar energy conversion, and degradation of organic pollutants.

  7. Evaluation of post-surface conditioning to improve interfacial adhesion in post-core restorations

    Directory of Open Access Journals (Sweden)

    Mylswamy Sumitha

    2011-01-01

    Full Text Available Aim : To examine the influence of different post-surface treatments on the interfacial strength between epoxy resin-based fiber posts and methacrylate-based resin composites that are employed as core build-up materials. Materials and Methods : Forty clear posts were divided into four groups of 10 each. The different surface treatments used were etching with alkaline potassium permanganate, 10% hydrogen peroxide, 37% phosphoric acid, and silanization alone. After etching and thorough rinsing, a single layer of silane was applied to the post surface. Then the post was placed in a rectangular plastic matrix and core bulid-up was done using Multi Core, a dual cured composite resin. A slab of uniform thickness, with the post in the center and the core build-up composite on either side was created. The specimens were cut so as to obtain microtensile sticks that were loaded in tension at a cross-head speed of 1 mm/min until failure. The statistical analysis was performed using two-way ANOVA and the paired T test for post-hoc comparisons. Results : The results achieved with potassium permanganate had a significant influence on microtensile interfacial bond strength values with the tested material. Conclusion : Surface chemical treatments of the resin phase of fiber posts enhance the silanization efficiency of the quartz fiber phase, so that the adhesion in the post/core unit may be considered as a net sum of chemical and micromechanical retention.

  8. An improved method for delta 15N measurements in ice cores

    Directory of Open Access Journals (Sweden)

    M. Leuenberger

    2008-02-01

    Full Text Available The use of isotopic ratios of nitrogen gas (δ15N trapped in ice cores as a paleothermometer to characterise abrupt climate changes is becoming a widespread technique. The versatility of the technique could be enhanced, for instance in quantifying small temperature changes during the last glacial period in Antarctic ice cores, by using high precision methods. In this paper, we outline a method for measuring δ15N to a precision of 0.006permil (1σ, n=9 from replicate ice core samples. The high precision results from removing oxygen, carbon dioxide and water vapour from the air extracted from ice cores. The advantage of the technique is that it does not involve correction for isobaric interference due to CO+ ions. We also highlight the importance of oxygen removal from the sample, and how it influences δ15N measurements. The results show that a small amount of oxygen in the sample can be detrimental to achieving an optimum precision in δ15N measurements of atmospheric nitrogen trapped ice core samples.

  9. Design and Performance Improvements of the Prototype Open Core Flywheel Energy Storage System

    Science.gov (United States)

    Pang, D.; Anand, D. K. (Editor); Kirk, J. A. (Editor)

    1996-01-01

    A prototype magnetically suspended composite flywheel energy storage (FES) system is operating at the University of Maryland. This system, designed for spacecraft applications, incorporates recent advances in the technologies of composite materials, magnetic suspension, and permanent magnet brushless motor/generator. The current system is referred to as an Open Core Composite Flywheel (OCCF) energy storage system. This paper will present design improvements for enhanced and robust performance. Initially, when the OCCF prototype was spun above its first critical frequency of 4,500 RPM, the rotor movement would exceed the space available in the magnetic suspension gap and touchdown on the backup mechanical bearings would occur. On some occasions it was observed that, after touchdown, the rotor was unable to re-suspend as the speed decreased. Additionally, it was observed that the rotor would exhibit unstable oscillations when the control system was initially turned on. Our analysis suggested that the following problems existed: (1) The linear operating range of the magnetic bearings was limited due to electrical and magnetic saturation; (2) The inductance of the magnetic bearings was affecting the transient response of the system; (3) The flywheel was confined to a small movement because mechanical components could not be held to a tight tolerance; and (4) The location of the touchdown bearing magnifies the motion at the pole faces of the magnetic bearings when the linear range is crucial. In order to correct these problems an improved design of the flywheel energy storage system was undertaken. The magnetic bearings were re-designed to achieve a large linear operating range and to withstand load disturbances of at least 1 g. The external position transducers were replaced by a unique design which were resistant to magnetic field noise and allowed cancellation of the radial growth of the flywheel at high speeds. A central rod was utilized to ensure the concentricity

  10. Effectiveness of core muscle strengthening for improving pain and dynamic balance among female patients with patellofemoral pain syndrome.

    Science.gov (United States)

    Chevidikunnan, Mohamed Faisal; Al Saif, Amer; Gaowgzeh, Riziq Allah; Mamdouh, Khaled A

    2016-05-01

    [Purpose] Patellofemoral pain syndrome is a frequent musculoskeletal disorder, which can result from core muscles instability that can lead to pain and altered dynamic balance. The objective of this study is to assess the effect of core muscle strengthening on pain and dynamic balance in female patients with patellofemoral pain syndrome. [Subjects and Methods] Twenty female patients with age ranging from 16 to 40 years with patellofemoral pain syndrome were divided into study (N=10) and control (N=10) groups. Both groups were given 4 weeks of conventional physical therapy program and an additional core muscle strengthening for the study group. The tools used to assess the outcome were Visual Analogue Scale and Star Excursion Balance Test. [Results] The results of the study show that participants in the study group revealed a significantly greater improvement in the intensity of pain and dynamic balance as compared to the control group. [Conclusion] Adding a core muscle-strengthening program to the conventional physical therapy management improves pain and dynamic balance in female patients with patellofemoral pain syndrome.

  11. An improved heat transfer configuration for a solid-core nuclear thermal rocket engine

    Science.gov (United States)

    Clark, John S.; Walton, James T.; Mcguire, Melissa L.

    1992-01-01

    Interrupted flow, impingement cooling, and axial power distribution are employed to enhance the heat-transfer configuration of a solid-core nuclear thermal rocket engine. Impingement cooling is introduced to increase the local heat-transfer coefficients between the reactor material and the coolants. Increased fuel loading is used at the inlet end of the reactor to enhance heat-transfer capability where the temperature differences are the greatest. A thermal-hydraulics computer program for an unfueled NERVA reactor core is employed to analyze the proposed configuration with attention given to uniform fuel loading, number of channels through the impingement wafers, fuel-element length, mass-flow rate, and wafer gap. The impingement wafer concept (IWC) is shown to have heat-transfer characteristics that are better than those of the NERVA-derived reactor at 2500 K. The IWC concept is argued to be an effective heat-transfer configuration for solid-core nuclear thermal rocket engines.

  12. Improvements in Sand Mold/Core Technology: Effects on Casting Finish

    Energy Technology Data Exchange (ETDEWEB)

    Prof. John J. Lannutti; Prof. Carroll E. Mobley

    2005-08-30

    In this study, the development and impact of density gradients on metal castings were investigated using sand molds/cores from both industry and from in-house production. In spite of the size of the castings market, almost no quantitative information about density variation within the molds/cores themselves is available. In particular, a predictive understanding of how structure and binder content/chemistry/mixing contribute to the final surface finish of these products does not exist. In this program we attempted to bridge this gap by working directly with domestic companies in examining the issues of surface finish and thermal reclamation costs resulting from the use of sand molds/cores. We show that these can be substantially reduced by the development of an in-depth understanding of density variations that correlate to surface finish. Our experimental tools and our experience with them made us uniquely qualified to achieve technical progress.

  13. The SSI and SKI review of the updated Final Safety Report for SFR 1 issued by SKB. Review report; SSI:s och SKI:s granskning av SKB:s uppdaterade Slutlig Saekerhetsrapport foer SFR 1. Granskningsrapport

    Energy Technology Data Exchange (ETDEWEB)

    Avila, Rodolfo; Jensen, Mikael; Larsson, Carl-Magnus; Lund, Ingemar; Loefgren, Tomas; Moberg, Leif; Norden, Maria; Wiebert, Anders [Swedish Radiation Protection Authority, Stockholm (Sweden); Berglund, Thomas; Dverstorp, Bjoern; Hedberg, Bengt; Kautsky, Fritz; Lilja, Christina; Simic, Eva; Stroemberg, Bo; Sundstroem, Benny; Toverud, Oeivind; Wingefors, Stig; Zika, Helmuth [Swedish Nuclear Power Inspectorate, Stockholm (Sweden)

    2003-11-01

    The repository for operational radioactive wastes in Sweden, SFR1, has been the object for a new safety assessment study by SKB (The Swedish Nuclear Fuel and Waste Management Co.). The findings of the review group will form the basis for decisions by the authorities on the provisions for the future operation of the repository.

  14. Implementation of project Safe in Amber. Verification study for SFR 1 SAR-08

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, Gavin; Herben, Martin; Lloyd, Pam; Rose, Danny; Smith, Chris; Barraclough, Ian (Enviros Consulting Ltd (GB))

    2008-03-15

    This report documents an exercise in which AMBER has been used to represent the models used in Project SAFE, a safety assessment undertaken on SFR 1. (AMBER is a flexible, graphical-user-interface based tool that allows users to build their own dynamic compartmental models to represent the migration, degradation and fate of contaminants in an environmental system. AMBER allows the user to assess routine, accidental and long-term contaminant release.) AMBER has been used to undertake assessment calculations on all of the disposal system, including all disposal tunnels and the Silo, the geosphere and several biosphere modules. The near-field conceptual models were implemented with minimal changes to the approach undertaken previously in Project SAFE. Model complexity varied significantly between individual disposal facilities increasing significantly from the BLA to the BTF and BMA tunnels and Silo. Radionuclide transport through the fractured granite geosphere was approximated using a compartment model approach in AMBER. Several biosphere models were implemented in AMBER including reasonable biosphere development, which considered the evolution of the Forsmark area from coastal to lacustrine to agricultural environments in response to land uplift. Parameters were sampled from distributions and simulations were run for 1,000 realisations. In undertaking the comparison of AMBER with the various codes and calculation tools used in Project SAFE it was necessary to undertake a detailed analysis of the modelling approach previously adopted, with particular focus given to the near-field models. As a result some discrepancies in the implementation of the models and documentation were noted. The exercise demonstrates that AMBER is fully capable of representing the features of the SFR 1 disposal system in a safety assessment suitable for SAR-08

  15. Estimation of retention factor of cesium in sodium pool under fuel pin failure scenario in SFR

    Energy Technology Data Exchange (ETDEWEB)

    Pradeep, Arjun [Computational Simulation Section, Safety Engineering Division, Nuclear and Safety Engineering Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Rao, P. Mangarjuna, E-mail: pmr@igcar.gov.in [Computational Simulation Section, Safety Engineering Division, Nuclear and Safety Engineering Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Nashine, B.K.; Chellapandi, P. [Computational Simulation Section, Safety Engineering Division, Nuclear and Safety Engineering Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer We model retention factor of cesium in infinite dilute solution of sodium pool. Black-Right-Pointing-Pointer We study variation in retention factor with cover gas temperature gradient. Black-Right-Pointing-Pointer Increasing height and temperature difference decreases the retention factor. Black-Right-Pointing-Pointer In infinite dilution regime retention factor is independent of cesium inventory. Black-Right-Pointing-Pointer The retention factor is useful in estimating source term in cover gas region. - Abstract: Radioactive source term in argon (Ar) cover gas region of the primary vessel due to cesium (Cs) leaked from the failed fuel pins into the primary coolant of Sodium cooled Fast Reactor (SFR) depends on its thermodynamic and kinetic behavior with the coolant sodium. Evaluation of this source term requires detailed knowledge on the distribution of Cs between large volume of the liquid sodium, and the inert Ar cover gas. Solute-solvent combination like liquid Cs and sodium, with relative volatility greater than unity, is an important system to be analyzed in the context of SFR safety. Distribution of Cs between Ar cover gas and liquid sodium pool is complicated by the imposition of temperature difference across the cover gas region and its resultant enrichment of the more volatile solute. An analytical model has been developed to obtain the geometry dependent Retention Factor (RF) of Cs in the sodium pool as a function of the height of cover gas, initial mass inventory of Cs, the temperature difference across the cover gas region (between the sodium pool surface and top roof bottom plate) for an infinite dilute solution of Cs in the sodium pool. The model predicted results are validated with available experimental results in the literature and found that they are fairly in good agreement. In the infinite dilute solution (IDS) regime sodium pool is having the retention capacity to keep the Cs from being released into

  16. Diagnostic value of imprint cytology during image-guided core biopsy in improving breast health care.

    Science.gov (United States)

    Masood, Shahla; Feng, Dian; Tutuncuoglu, Osman; Fischer, Gabor; Bakhshandeh, Maryam; Bertholf, Roger L; Wolfson, David

    2011-01-01

    The aim of this study was to investigate the accuracy of imprint cytology (IC) of breast core biopsy under ultrasound guidance and to assess the value of a rapid on-site preliminary diagnosis of breast lesions. A total of 437 breast core needle biopsies under ultrasound guidance with touch imprint cytology, histology, and final diagnosis were reviewed. These cases were collected from archived files at our institution. Of 437 core biopsies, IC classified 241 (55%) as benign; 22 (5%) as probably benign; 28 (6%) as probably malignant; 107 (25%) as malignant; and 39 (9%) as inadequate for IC diagnosis. Histological classifications for the 437 cases were: 285 (65%) benign; 132 (30%) malignant; 16 (4%) atypical hyperplasia; and 4 (1%) inadequate specimen. The overall sensitivity and specificity indices of IC were 95% and 96%, respectively, for benign and probably benign lesions vs malignant and probably malignant breast lesions. The overall positive and negative predictive values were 91% and 97%, respectively. The overall accuracy was 95% (379 of 398 cases, excluding specimens inadequate for IC diagnosis). IC of ultrasound-guided core needle biopsy provides a rapid and reliable preliminary diagnosis for breast lesions; it also serves as a means to verify the adequacy of biopsy specimens and to optimize the biopsy procedure. Use of IC may reduce anxiety in patients with benign lesions and expedite the diagnosis and assessment of treatment options in patients with breast cancer.

  17. Improved bounds on the phase transition for the hard-core model in 2 dimensions

    NARCIS (Netherlands)

    Vera, Juan C.; Vigoda, E.; Yang, L.

    2015-01-01

    For the hard-core lattice gas model defined on independent sets weighted by an activity $\\lambda$, we study the critical activity $\\lambda_c(\\mathbb{Z}^2)$ for the uniqueness/nonuniqueness threshold on the 2-dimensional integer lattice $\\mathbb{Z}^2$. The conjectured value of the critical activity i

  18. Assessing the Common Core Standards: Opportunities for Improving Measures of Instruction

    Science.gov (United States)

    Porter, Andrew; McMaken, Jennifer; Hwang, Jun; Yang, Rui

    2011-01-01

    This article responds to comments on the authors' "Educational Researcher" article "Common Core Standards: The New U.S. Intended Curriculum" (April 2011). The authors note points of agreement and difference with the commentators. They observe that Cobb and Jackson, in their response, and Beach, in his, appear to accept the authors' methods and…

  19. Surrogates based multi-criteria predesign methodology of Sodium-cooled Fast Reactor cores – Application to CFV-like cores

    Energy Technology Data Exchange (ETDEWEB)

    Fabbris, Olivier [CEA DEN/DER/SESI, 13108 Saint-Paul-Lez-Durance (France); Dardour, Saied, E-mail: saied.dardour@cea.fr [CEA DEN/DER/SESI, 13108 Saint-Paul-Lez-Durance (France); Blaise, Patrick [CEA DEN/DER/SPEX, 13108 Saint-Paul-Lez-Durance (France); Ferrasse, Jean-Henry [Aix-Marseille Université, CNRS, ECM, M2P2 UMR 7340, 13451 Marseille (France); Saez, Manuel [CEA DEN/DER/SESI, 13108 Saint-Paul-Lez-Durance (France)

    2016-08-15

    Highlights: • We developed an ERANOS calculation scheme to evaluate the neutronics of CFV cores. • We used this scheme to simulate a number if cores within a predefined study space. • Simulation results were used to build surrogate models describing CFV neutronics. • These models were used to carry on global sensitivity analyses. • The methodology helped identify the most important core design parameters. - Abstract: The Sodium-cooled Fast Reactor (SFR) core predesign process is commonly realized on the basis of expert advices and local parametric studies. As such, in-deep knowledge of physical phenomena avoids an important number of expensive simulations. However, the study space is explored only partially. To ease the computational burden metamodels, or surrogate models, can be used, to quickly evaluate the performances of a wide set of different cores, individually defined by a set of parameters (pellet diameter, fissile height…), in the study space. This paper presents the development of a simplified neutronics ERANOS reference core calculation scheme that is then implemented in the construction of the Design of Experiment (DOE) database. The surrogate models for SFR CFV-like cores performances are developed, biases and uncertainties are quantified against the CFV-v1 version. Global Sensitivity Analysis also allowed highlighting antagonist performances for the design and to propose two alternative core configurations. A broadened application of the method with an optimization of a CFV-like core is also detailed. The Pareto front of the seven selected performance parameters has been studied using eleven surrogate models, based on Artificial Neural Network (ANN). The optimization demonstrates that the CFV-v1, designed using Best Estimate codes, under given performance constraints, is Pareto optimal: no other configuration is highlighted from the Multi-Objective Optimization (MOO) study. Further MOO analysis, including a specific study on impact of new

  20. Improved Fabrication of Ceramic Matrix Composite/Foam Core Integrated Structures

    Science.gov (United States)

    Hurwitz, Frances I.

    2009-01-01

    The use of hybridized carbon/silicon carbide (C/SiC) fabric to reinforce ceramic matrix composite face sheets and the integration of such face sheets with a foam core creates a sandwich structure capable of withstanding high-heatflux environments (150 W/cm2) in which the core provides a temperature drop of 1,000 C between the surface and the back face without cracking or delamination of the structure. The composite face sheet exhibits a bilinear response, which results from the SiC matrix not being cracked on fabrication. In addition, the structure exhibits damage tolerance under impact with projectiles, showing no penetration to the back face sheet. These attributes make the composite ideal for leading edge structures and control surfaces in aerospace vehicles, as well as for acreage thermal protection systems and in high-temperature, lightweight stiffened structures. By tailoring the coefficient of thermal expansion (CTE) of a carbon fiber containing ceramic matrix composite (CMC) face sheet to match that of a ceramic foam core, the face sheet and the core can be integrally fabricated without any delamination. Carbon and SiC are woven together in the reinforcing fabric. Integral densification of the CMC and the foam core is accomplished with chemical vapor deposition, eliminating the need for bond-line adhesive. This means there is no need to separately fabricate the core and the face sheet, or to bond the two elements together, risking edge delamination during use. Fibers of two or more types are woven together on a loom. The carbon and ceramic fibers are pulled into the same pick location during the weaving process. Tow spacing may be varied to accommodate the increased volume of the combined fiber tows while maintaining a target fiber volume fraction in the composite. Foam pore size, strut thickness, and ratio of face sheet to core thickness can be used to tailor thermal and mechanical properties. The anticipated CTE for the hybridized composite is managed by

  1. Star formation in the local Universe from the CALIFA sample. I. Calibrating the SFR using integral field spectroscopy data

    Science.gov (United States)

    Catalán-Torrecilla, C.; Gil de Paz, A.; Castillo-Morales, A.; Iglesias-Páramo, J.; Sánchez, S. F.; Kennicutt, R. C.; Pérez-González, P. G.; Marino, R. A.; Walcher, C. J.; Husemann, B.; García-Benito, R.; Mast, D.; González Delgado, R. M.; Muñoz-Mateos, J. C.; Bland-Hawthorn, J.; Bomans, D. J.; Del Olmo, A.; Galbany, L.; Gomes, J. M.; Kehrig, C.; López-Sánchez, Á. R.; Mendoza, M. A.; Monreal-Ibero, A.; Pérez-Torres, M.; Sánchez-Blázquez, P.; Vilchez, J. M.; Califa Collaboration

    2015-12-01

    Context. The star formation rate (SFR) is one of the main parameters used to analyze the evolution of galaxies through time. The need for recovering the light reprocessed by dust commonly requires the use of low spatial resolution far-infrared data. Recombination line luminosities provide an alternative, although uncertain dust-extinction corrections based on narrowband imaging or long-slit spectroscopy have traditionally posed a limit to their applicability. Integral field spectroscopy (IFS) is clearly the way to overcome this kind of limitation. Aims: We obtain integrated Hα, ultraviolet (UV) and infrared (IR)-based SFR measurements for 272 galaxies from the CALIFA survey at 0.005 extinction-corrected Hα luminosities provide a good measure of the SFR and to shed light on the origin of the discrepancies between tracers. Updated calibrations referred to Hα are provided. The well-defined selection criteria and large statistics allow us to carry out this analysis globally and split by properties, including stellar mass and morphological type. Methods: We derive integrated, extinction-corrected Hα fluxes from CALIFA, UV surface and asymptotic photometry from GALEX and integrated WISE 22 μm and IRAS fluxes. Results: We find that the extinction-corrected Hα luminosity agrees with the hybrid updated SFR estimators based on either UV or Hα plus IR luminosity over the full range of SFRs (0.03-20 M⊙ yr-1). The coefficient that weights the amount of energy produced by newly-born stars that is reprocessed by dust on the hybrid tracers, aIR, shows a large dispersion. However, this coefficient does not became increasingly small at high attenuations, as expected if significant highly-obscured Hα emission were missed, i.e., after a Balmer decrement-based attenuation correction is applied. Lenticulars, early-type spirals, and type-2 AGN host galaxies show smaller coefficients because of the contribution of optical photons and AGN to dust heating. Conclusions: In the

  2. Site investigation SFR. Fracture mineralogy including identification of uranium phases and hydrochemical characterisation of groundwater in borehole KFR106

    Energy Technology Data Exchange (ETDEWEB)

    Sandstroem, Bjoern [WSP Sverige AB, Goeteborg (Sweden); Nilsson, Kersti [Geosigma AB, Uppsala (Sweden); Tullborg, Eva-Lena [Terralogica AB, Graabo (Sweden)

    2011-12-15

    This report presents the fracture mineralogy and hydrochemistry of borehole KFR106. The most abundant fracture minerals in the examined drill core samples are clay minerals, calcite, quartz and adularia; chlorite is also common but is mostly altered and found interlayered with corrensite. The most common clay mineral is a mixed layer clay consisting of illite-smectite. Pyrite, galena, chalcopyrite, barite (-celestine) and hematite are also commonly found in the fractures, but usually in trace amounts. Other minerals identified in the examined fractures are U-phosphate, pitchblende, U(Ca)-silicate, asphaltite, biotite, monazite, fluorite, titanite, sericite, xenotime, rutile and (Ca, REEs)-carbonate. Uranium has been introduced, mobilised and reprecipitated during at least four different episodes: 1) Originally, during emplacement of U-rich pegmatites, probably as uraninite. 2) At a second event, uranium was mobilised under brittle conditions during formation of breccia/cataclasite. Uraninite was altered to pitchblende and partly coffinitised. Mobilised uranium precipitated as pitchblende closely associated with hematite and chlorite in cataclasite and fracture sealings prior to 1,000 Ma. 3) During the Palaeozoic U was remobilised and precipitated as U-phosphate on open fracture surfaces. 4) An amorphous U-silicate has also been found in open fractures; the age of this precipitation is not known but it is inferred to be Palaeozoic or younger. Groundwater was sampled in two sections in borehole KFR106 with pumping sequences of about 6 days for each section. The samples from sections KFR106:1 and KFR106:2 (260-300 m and 143-259 m borehole length, i.e. -261 and -187 m.a.s.l. mid elevation of the section, respectively) were taken in November 2009 and yielded groundwater chemistry data in accordance with SKB chemistry class 3 and 5. In section KFR106:1 and KFR106:2, the chloride contents were 850 and 1,150 mg/L and the drilling water content 6 and 4%, respectively

  3. Complete Au@ZnO core-shell nanoparticles with enhanced plasmonic absorption enabling significantly improved photocatalysis

    Science.gov (United States)

    Sun, Yiqiang; Sun, Yugang; Zhang, Tao; Chen, Guozhu; Zhang, Fengshou; Liu, Dilong; Cai, Weiping; Li, Yue; Yang, Xianfeng; Li, Cuncheng

    2016-05-01

    Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic absorption in the visible range due to the Au NP cores. They also show a significantly improved photocatalytic performance in comparison with their single-component counterparts, i.e., the Au NPs and ZnO NPs. Moreover, the high catalytic activity of the as-synthesized Au@ZnO core-shell NPs can be maintained even after many cycles of photocatalytic reaction. Our results shed light on the fact that the Au@ZnO core-shell NPs represent a promising class of candidates for applications in plasmonics, surface-enhanced spectroscopy, light harvest devices, solar energy conversion, and degradation of organic pollutants.Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic

  4. Predicting core losses and efficiency of SRM in continuous current mode of operation using improved analytical technique

    Energy Technology Data Exchange (ETDEWEB)

    Parsapour, Amir, E-mail: amirparsapour@gmail.com [Department of Electrical Engineering, University of Isfahan, Isfahan (Iran, Islamic Republic of); Dehkordi, Behzad Mirzaeian, E-mail: mirzaeian@eng.ui.ac.ir [Department of Electrical Engineering, University of Isfahan, Isfahan (Iran, Islamic Republic of); Moallem, Mehdi, E-mail: moallem@cc.iut.ac.ir [Department of Electrical Engineering, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of)

    2015-03-15

    In applications in which the high torque per ampere at low speed and rated power at high speed are required, the continuous current method is the best solution. However, there is no report on calculating the core loss of SRM in continuous current mode of operation. Efficiency and iron loss calculation which are complex tasks in case of conventional mode of operation is even more involved in continuous current mode of operation. In this paper, the Switched Reluctance Motor (SRM) is modeled using finite element method and core loss and copper loss of SRM in discontinuous and continuous current modes of operation are calculated using improved analytical techniques to include the minor loop losses in continuous current mode of operation. Motor efficiency versus speed in both operation modes is obtained and compared. - Highlights: • Continuous current method for Switched Reluctance Motor (SRM) is explained. • An improved analytical technique is presented for SRM core loss calculation. • SRM losses in discontinuous and continuous current operation modes are presented. • Effect of mutual inductances on SRM performance is investigated.

  5. Black-Scholes-Schrödinger-Zipf-Mandelbrot model framework for improving a study of the coauthor core score

    Science.gov (United States)

    Rotundo, Giulia

    2014-06-01

    The data and findings by Miskiewicz (2013) on the relationship between the number (J) of publications ranked according to their decreasing importance, for some scientist with her/his coauthors (CA), i.e. J∝1/rα, as found in Ausloos (2013), when specific types of publications, i.e. proceedings (in a generalized sense) and peer-review journals, are considered, are reexamined along the Zipf-Mandelbrot law Mandelbrot (1977), i.e. J∝1/(. The statistics are much improved. The exponent α and ζ are compared. The ma core value, i.e. the core number of CAs [1] is unaffected, of course. A Black-Scholes-Schrödinger model framework is proposed to describe the findings.

  6. Integrating multi-scale geophysical and drill-core data to improve hydraulic characterization of continental sedimentary basins

    Science.gov (United States)

    Kukowski, Nina; Methe, Pascal; Goepel, Andreas

    2017-04-01

    Physical properties of rocks in the uppermost continental crust e.g. sedimentary basins are very heterogeneously distributed and anisotropic making it necessary to perform advanced post processing techniques on geophysical data. Whereas e.g. electrical resistivity or seismic tomography allow only for identifying physical properties' variability on a scale from roughly several tens of metres to several hundred metres, drill cores reveal physical heterogeneity on the cm-scale. To study the impact of small scale acoustic and hydraulic heterogeneity on fluid flow in a sedimentary basin we use combined data sets from the Thuringian Basin in Germany, a small southern extension of the North German Basin characterised by Permian to Triassic sediments. Our data sets consist of three reflection seismic lines acquired within the framework of the multidisciplinary project INFLUINS (INtegrated FLUid dynamics IN Sedimentary basins) and as site survey for deep drilling, geophysical logging data from a 1,179 m deep drill hole in the centre of the Thuringian Basin, and Multi Sensor Core Logger (MSCL) data of the cores recovered from this drill hole. Geophysical borehole logging was performed immediate after drilling on the highest vertical resolution (about 10 cm) possible using state of the art commercial logging tools. MSCL-data were acquired at an even higher resolution of about 1 to 2 cm , which enables both, calibrating logging data and zooming in the spatial heterogeneity of physical properties. These measurements are complemented with laboratory measurements of rock physical properties (e.g. thermal conductivity, permeability) using selected core samples. Here, we mainly focus on seismic (sonic velocity, density) and hydraulic (porosity, permeability) parameters. This multi-methodological approach allows us on the one hand to estimate improved local to regional average values for physical parameters but most importantly also to highlight the role of thin layers, the physical

  7. Improving accuracy of the calculation of in-core power distributions for light water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Tsuiki, M.; Beere, W.H. (Institute for energy technology, OECD Halden Reactor Project (Norway))

    2009-10-15

    Comparisons have been made of VNEM prototype system to the measured data obtained from Ringhals unit 3 NPP at its beginning of life, hot-stand-by state. Three cases with difference control rod bank positions and Boron concentrations have been compared: Case 1: nearly all rod banks withdrawn, Boron = 1315 ppm Case 2: bank C = nearly half-inserted, bank D = fully inserted, Boron = 1131 ppm Case 3: banks C and D = fully inserted, Boron = 1060 ppm The results can be summarized as: error: maximum detector reading (%) error: keff (%) Case 1 -2.1 -0.175 Case 2 1.5 -0.022 Case 3 -0.5 -0.044 Excellent agreement was observed in the comparison of the neutron detector readings and the core eigenvalues. The method of core modelling and parameters used in calculation of VNEM is completely the same as the 'PWR standard option' determined from similar comparisons of VNEM and other PWRs. No empirical, or any sort of adjustment was done. (author)

  8. Evolution of the specific Star Formation Rate Function at z<1.4 - Dissecting the mass-SFR plane in COSMOS and GOODS

    CERN Document Server

    Ilbert, O; Floc'h, E Le; Aussel, H; Bethermin, H; Capak, P; Hsieh, B C; Kajisawa, M; Fevre, O Le; Lee, N; Lilly, S; McCracken, H J; Michel-Dansac, L; Moutard, T; Renzini, A; Salvato, M; Sanders, D B; Scoville, N; Sheth, K; Smolcic, V; Taniguchi, Y; Tresse, L

    2014-01-01

    The relation between the stellar mass and the star formation rate characterizes how the instantaneous star formation is determined by the galaxy past star formation history and by the growth of the dark matter structures. We deconstruct the M-SFR plane by measuring the specific SFR functions in several stellar mass bins from z=0.2 out to z=1.4. Our analysis is primary based on a MIPS 24$\\mu m$ selected catalogue combining the COSMOS and GOODS surveys. We estimate the SFR by combining mid- and far-infrared data for 20500 galaxies. The sSFR functions are derived in four stellar mass bins within the range 9.5SFR relation. Secondly, we find a mass-dependent evolution of the median sSFR with redshift varying as $sSFR \\propto (1+z)^{b}$, with $b$ increasing from $b=2.88$ to $b=3.78$ between $M=10^{9.75}Msun$ and $M=10^{11.1}Msun$, respectively. At low masses, this evolution is consistent with t...

  9. A Critical Look at the Mass-Metallicity-SFR Relation in the Local Universe: Non-parametric Analysis Framework and Confounding Systematics

    CERN Document Server

    Salim, Samir; Ly, Chun; Brinchmann, Jarle; Davé, Romeel; Dickinson, Mark; Salzer, John J; Charlot, Stéphane

    2014-01-01

    It has been proposed that the mass-metallicity relation of galaxies exhibits a secondary dependence on star formation rate (SFR), and that the resulting M-Z-SFR relation may be redshift-invariant, i.e., "fundamental." However, conflicting results on the character of the SFR dependence, and whether it exists, have been reported. To gain insight into the origins of the conflicting results, we (a) devise a non-parametric, astrophysically-motivated analysis framework based on the offset from the star-forming ("main") sequence at a given stellar mass (relative specific SFR), (b) apply this methodology and perform a comprehensive re-analysis of the local M-Z-SFR relation, based on SDSS, GALEX, and WISE data, and (c) study the impact of sample selection, and of using different metallicity and SFR indicators. We show that metallicity is anti-correlated with specific SFR regardless of the indicators used. We do not find that the relation is spurious due to correlations arising from biased metallicity measurements, or ...

  10. Towards a core ontology for integrating ecological and environmental ontologies to enable improved data interoperability

    Science.gov (United States)

    Bowers, S.; Madin, J.; Jones, M.; Schildhauer, M.; Ludaescher, B.

    2007-12-01

    Research in the ecological and environmental sciences increasingly relies on the integration of traditionally small, focused studies to form larger datasets for synthetic analyses. However, a broad range of data types, structures, and semantic subtleties occur in ecological data, making data discovery and integration a difficult and time-consuming task. Our work focuses on capturing the subtleties of scientific data through semantic annotations, which involve linking ecological data to concepts and relationships in domain-specific ontologies, thereby enabling more advanced forms of data discovery and integration. A variety of ontologies related to ecological data are actively being developed, ranging from low-level and highly focused vocabularies to high-level models and classifications. However, as the number of ontologies and their included terms increase, organizing these into a coherent framework useful for data annotation becomes increasingly complex (we note that similar issues have been recognized within the molecular biology and bioinformatics communities). We describe a core ontology model for semantic annotation that provides a structured approach for integrating the growing number of ecology-relevant ontologies. The ontology defines the notion of "scientific observation" as a unifying concept for capturing the basic semantics of ecological data. Observations are distinguished at the level of the entity (e.g., location, time, thing, concept), and characteristics of an entity (e.g., height, name, color) are measured (named or classified) as data. The ontology permits observations to be related via context (such as spatial or temporal containment), further supporting the discovery and automated comparison and alignment (e.g., merging) of heterogeneous data. The core ontology also defines a set of extension points that can be used to either directly build new domain ontologies (as extension ontologies), or to provide a common basis to which existing

  11. Evaluation of a conditioning method to improve core-veneer bond strength of zirconia restorations.

    Science.gov (United States)

    Teng, Jili; Wang, Hang; Liao, Yunmao; Liang, Xing

    2012-06-01

    The high strength and fracture toughness of zirconia have supported its extensive application in esthetic dentistry. However, the fracturing of veneering porcelains remains one of the primary causes of failure. The purpose of this study was to evaluate, with shear bond strength testing, the effect of a simple and novel surface conditioning method on the core-veneer bond strength of a zirconia ceramic system. The shear bond strength of a zirconia core ceramic to the corresponding veneering porcelain was tested by the Schmitz-Schulmeyer method. Thirty zirconia core specimens (10 × 5 × 5 mm) were layered with a veneering porcelain (5 × 3 × 3 mm). Three different surface conditioning methods were evaluated: polishing with up to 1200 grit silicon carbide paper under water cooling, airborne-particle abrasion with 110 μm alumina particles, and modification with zirconia powder coating before sintering. A metal ceramic system was used as a control group. All specimens were subjected to shear force in a universal testing machine at a crosshead speed of 0.5 mm/min. The shear bond strength values were analyzed with 1-way ANOVA and Tukey's post hoc pairwise comparisons (α=.05). The fractured specimens were examined with a scanning electron microscope to observe the failure mode. The mean (SD) shear bond strength values in MPa were 47.02 (6.4) for modified zirconia, 36.66 (8.6) for polished zirconia, 39.14 (6.5) for airborne-particle-abraded zirconia, and 46.12 (7.1) for the control group. The mean bond strength of the control (P=.028) and modified zirconia groups (P=.014) was significantly higher than that of the polished zirconia group. The airborne-particle-abraded group was not significantly different from any other group. Scanning electron microscopy evaluation showed that cohesive fracture in the veneering porcelain was the predominant failure mode of modified zirconia, while the other groups principally fractured at the interface. Modifying the zirconia surface

  12. Can Technology Improve Large Class Learning? The Case of an Upper-Division Business Core Class

    Science.gov (United States)

    Stanley, Denise

    2013-01-01

    Larger classes are often associated with lower student achievement. The author tested the hypothesis that the introduction of personal response systems significantly improves scores in a 250-seat classroom, through the channels of improved attendance and engagement. She focused on how continuous participation with the technology could change…

  13. Total Automation for the Core Laboratory: Improving the Turnaround Time Helps to Reduce the Volume of Ordered STAT Tests.

    Science.gov (United States)

    Ialongo, Cristiano; Porzio, Ottavia; Giambini, Ilio; Bernardini, Sergio

    2016-06-01

    The transition to total automation represents the greatest leap for a clinical laboratory, characterized by a totally new philosophy of process management. We have investigated the impact of total automation on core laboratory efficiency and its effects on the clinical services related to STAT tests. For this purpose, a 47-month retrospective study based on the analysis of 44,212 records of STAT cardiac troponin I (CTNI) tests was performed. The core laboratory reached a new efficiency level 3 months after the implementation of total automation. Median turnaround time (TAT) was reduced by 14.9±1.5 min for the emergency department (p < 0.01), reaching 41.6±1.2 min. In non-emergency departments, median TAT was reduced by 19.8±2.2 min (p < 0.01), reaching 52±1.3 min. There was no change in the volume of ordered STAT CTNI tests by the emergency department (p = 0.811), whereas for non-emergency departments there was a reduction of 115.7±50 monthly requests on average (p = 0.026). The volume of ordered tests decreased only in time frames of the regular shift following the morning round. Thus, total automation significantly improves the core laboratory efficiency in terms of TAT. As a consequence, the volume of STAT tests ordered by hospital departments (except for the emergency department) decreased due to reduced duplicated requests.

  14. Core-shell nanoparticles optical sensors - Rational design of zinc ions fluorescent nanoprobes of improved analytical performance

    Science.gov (United States)

    Woźnica, Emilia; Gasik, Joanna; Kłucińska, Katarzyna; Kisiel, Anna; Maksymiuk, Krzysztof; Michalska, Agata

    2017-10-01

    In this work the effect of affinity of an analyte to a receptor on the response of nanostructural fluorimetric probes is discussed. Core-shell nanoparticles sensors are prepared that benefit from the properties of the phases involved leading to improved analytical performance. The optical transduction system chosen is independent of pH, thus the change of sample pH can be used to control the analyte - receptor affinity through the ;conditional; binding constant prevailing within the lipophilic phase. It is shown that by affecting the ;conditional; binding constant the performance of the sensor can be fine-tuned. As expected, increase in ;conditional; affinity of the ligand embedded in the lipophilic phase to the analyte results in higher sensitivity over narrow concentration range - bulk reaction and sigmoidal shape response of emission intensity vs. logarithm of concentration changes. To induce a linear dependence of emission intensity vs. logarithm of analyte concentration covering a broad concentration range, a spatial confinement of the reaction zone is proposed, and application of core-shell nanostructures. The core material, polypyrrole nanospheres, is effectively not permeable for the analyte - ligand complex, thus the reaction is limited to the outer shell layer of the polymer prepared from poly(maleic anhydride-alt-1-octadecene). For herein introduced system a linear dependence of emission intensity vs. logarithm of Zn2+ concentration was obtained within the range from 10-7 to 10-1 M.

  15. Specifications for a coupled neutronics thermal-hydraulics SFR test case

    Science.gov (United States)

    Tassone, A.; Smirnov, A. D.; Tikhomirov, G. V.

    2017-01-01

    Coupling neutronics/thermal-hydraulics calculations for the design of nuclear reactors are a growing trend in the scientific community. This approach allows to properly represent the mutual feedbacks between the neutronic distribution and the thermal-hydraulics properties of the materials composing the reactor, details which are often lost when separate analysis are performed. In this work, a test case for a generation IV sodium-cooled fast reactor (SFR), based on the ASTRID concept developed by CEA, is proposed. Two sub-assemblies (SA) characterized by different fuel enrichment and layout are considered. Specifications for the test case are provided including geometrical data, material compositions, thermo-physical properties and coupling scheme details. Serpent and ANSYS-CFX are used as reference in the description of suitable inputs for the performing of the benchmark, but the use of other code combinations for the purpose of validation of the results is encouraged. The expected outcome of the test case are the axial distribution of volumetric power generation term (q‴), density and temperature for the fuel, the cladding and the coolant.

  16. Project SAFE. Modelling of long-term concrete degradation processes in the Swedish SFR repository

    Energy Technology Data Exchange (ETDEWEB)

    Hoeglund, L.O. [Kemakta Konsult AB, Stockholm (Sweden)

    2001-04-01

    This study concerns the leaching of concrete barriers, in particular the silo construction, in the Swedish SFR repository for low and intermediate level radioactive waste. A conceptual model for the leaching of concrete in a saline groundwater has been proposed based on the increased understanding achieved from research studies presented in the literature. The conceptual model has been used to set up a numerical model for the complex chemical interactions between the cement minerals of the concrete with the groundwater. The calculations show that various chemical reactions are expected to occur in the concrete over time. Different cases have been calculated. The results show that the chemical conditions in the concrete barriers will maintain alkaline for long time. In the most exposed parts of the concrete a high degree of leaching can be expected during the considered 10,000 years, whereas only for the most unfavourable assumptions (initially fractured concrete with groundwater flow-through) the inner parts of the concrete will be degraded to any significant degree.

  17. Superparamagnetic iron oxide/chitosan core/shells for hyperthermia application: Improved colloidal stability and biocompatibility

    Science.gov (United States)

    Patil, R. M.; Shete, P. B.; Thorat, N. D.; Otari, S. V.; Barick, K. C.; Prasad, A.; Ningthoujam, R. S.; Tiwale, B. M.; Pawar, S. H.

    2014-04-01

    Superparamagnetic magnetite nanoparticles are of great interest due to their potential biomedical applications. In the present investigation, Fe3O4 magnetic nanoparticles were prepared by alkaline precipitation using ferrous chloride as the sole source. An amphiphilic polyelectrolyte with the property of biocompatibility and functional carboxyl groups was used as a stabilizer to prepare a well-dispersed suspension of superparamagnetic Fe3O4 nanoparticles. The final material composed of Fe3O4 core and chitosan (CH) shell was produced. The amino groups of CH coated on Fe3O4 nanoparticles were further cross linked using glutaraldehyde (GLD) for stable coating. FTIR spectra, XPS and TGA confirmed the coating of CH/GLD on the surface of Fe3O4 nanoparticles. XRD patterns indicate the pure phase Fe3O4 with a spinel structure. The nanoparticles were superparamagnetic at room temperature with saturation magnetization values for bare and coated nanoparticles which were 51.68 emu/g and 48.60 emu/g, respectively. Zeta potential values showed higher colloidal stability of coated nanoparticles than the bare one. Cytotoxicity study up to 2 mg mL-1 concentration showed no drastic change in cell viability of nanoparticles after coating. Also, coated nanoparticles showed increased SAR value, making them suitable for hyperthermia therapy application.

  18. Parallel Algorithm Core: A Novel IPSec Algorithm Engine for Both Exploiting Parallelism and Improving Scalability

    Institute of Scientific and Technical Information of China (English)

    Dong-Nian Cheng; Yu-Xiang Hu; Cai-Xia Liu

    2008-01-01

    To deal with the challenges of both computation-complexity and algorithm-scalability posed to the design of an IPSec engine, we develop PAC (parallel algorithm core), called PAC, employed in an IPSec engine, which can meet requirements of both exploiting parallelism existing in IPSec packets and offering scalability in both the scales and types of cryptographic algorithms. With three kinds of parallelism and two kinds of transparency defined, a novel hierarchy of the specifically-designed parallel structure for PAC is presented, followed by corresponding mechanisms. With a simulation, the scalability of PAC is examined. For the purpose of performance evaluation, a Quasi Birth-and-Death (QBD) process is then established to model a simplified version of the proposed PAC. Performance evaluation of PAC in terms of two representative measures, throughput and mean packet waiting time, is numerically investigated. A comparison study is done on a simulation basis. Conclusions are finally drawn for providing a helpful guideline for both the design and implementation of our proposal.

  19. Improving core outcome set development: qualitative interviews with developers provided pointers to inform guidance.

    Science.gov (United States)

    Gargon, Elizabeth; Williamson, Paula R; Young, Bridget

    2017-06-01

    The objective of the study was to explore core outcome set (COS) developers' experiences of their work to inform methodological guidance on COS development and identify areas for future methodological research. Semistructured, audio-recorded interviews with a purposive sample of 32 COS developers. Analysis of transcribed interviews was informed by the constant comparative method and framework analysis. Developers found COS development to be challenging, particularly in relation to patient participation and accessing funding. Their accounts raised fundamental questions about the status of COS development and whether it is consultation or research. Developers emphasized how the absence of guidance had affected their work and identified areas where guidance or evidence about COS development would be useful including, patient participation, ethics, international development, and implementation. They particularly wanted guidance on systematic reviews, Delphi, and consensus meetings. The findings raise important questions about the funding, status, and process of COS development and indicate ways that it could be strengthened. Guidance could help developers to strengthen their work, but over specification could threaten quality in COS development. Guidance should therefore highlight common issues to consider and encourage tailoring of COS development to the context and circumstances of particular COS. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Lipid-Core Nanocapsules Improved Antiedematogenic Activity of Tacrolimus in Adjuvant-Induced Arthritis Model.

    Science.gov (United States)

    Friedrich, Rossana B; Coradini, Karine; Fonseca, Francisco N; Guterres, Silvia S; Beck, Ruy C R; Pohlmann, Adriana R

    2016-02-01

    Despite significant technological advances, rheumatoid arthritis remains an incurable disease with great impact on the life quality of patients. We studied the encapsulation of tacrolimus in lipidcore nanocapsules (TAC-LNC) as a strategy to enhance its systemic anti-arthritic properties. TAC-LNC presented unimodal distribution of particles with z-average diameter of 212 +/- 11, drug content close to the theoretical value (0.80 mg mL(-1)), and 99.43% of encapsulation efficiency. An in vitro sustained release was determined for TAC-LNC with anomalous transport mechanism (n = 0.61). In vivo studies using an arthritis model induced by Complete Freund's Adjuvant demonstrated that the animals treated with TAC-LNC presented a significantly greater inhibition of paw oedema after intraperitoneal administration. Furthermore, the encapsulation of TAC in lipid-core nanocapsules was potentially able to prevent hyperglycemia in the animals. In conclusion, TAC-LNC was prepared with 100% yield of nanoscopic particles having satisfactory characteristics for systemic use. This formulation represents a promising strategy to the treatment of rheumatoid arthritis in the near future.

  1. Laser Modified ZnO/CdSSe Core-Shell Nanowire Arrays for Micro-Steganography and Improved Photoconduction

    Science.gov (United States)

    Lu, Junpeng; Liu, Hongwei; Zheng, Minrui; Zhang, Hongji; Lim, Sharon Xiaodai; Tok, Eng Soon; Sow, Chorng Haur

    2014-09-01

    Arrays of ZnO/CdSSe core/shell nanowires with shells of tunable band gaps represent a class of interesting hybrid nanomaterials with unique optical and photoelectrical properties due to their type II heterojunctions and chemical compositions. In this work, we demonstrate that direct focused laser beam irradiation is able to achieve localized modification of the hybrid structure and chemical composition of the nanowire arrays. As a result, the photoresponsivity of the laser modified hybrid is improved by a factor of ~3. A 3D photodetector with improved performance is demonstrated using laser modified nanowire arrays overlaid with monolayer graphene as the top electrode. Finally, by controlling the power of the scanning focused laser beam, micropatterns with different fluorescence emissions are created on a substrate covered with nanowire arrays. Such a pattern is not apparent when imaged under normal optical microscopy but the pattern becomes readily revealed under fluorescence microscopy i.e. a form of Micro-Steganography is achieved.

  2. Star Formation in the Local Universe from the CALIFA sample. I. Calibrating the SFR using IFS data

    CERN Document Server

    Catalán-Torrecilla, C; Castillo-Morales, A; Iglesias-Páramo, J; Sánchez, S F; Kennicutt, R C; Pérez-González, P G; Marino, R A; Walcher, C J; Husemann, B; García-Benito, R; Mast, D; Delgado, R M González; Muñoz-Mateos, J C; Bland-Hawthorn, J; Bomans, D J; del Olmo, A; Galbany, L; Gomes, J M; Kehrig, C; López-Sánchez, Á R; Mendoza, M A; Monreal-Ibero, A; Pérez-Torres, M; Sánchez-Blázquez, P; Vilchez, J M

    2015-01-01

    The Star Formation Rate (SFR) is one of the main parameters used to analyze the evolution of galaxies through time. The need for recovering the light reprocessed by dust commonly requires the use of low spatial resolution far-infrared data. Recombination-line luminosities provide an alternative, although uncertain dust-extinction corrections based on narrow-band imaging or long-slit spectroscopy have traditionally posed a limit to their applicability. Integral Field Spectroscopy (IFS) is clearly the way to overcome such limitation. We obtain integrated H{\\alpha}, ultraviolet (UV) and infrared (IR)-based SFR measurements for 272 galaxies from the CALIFA survey at 0.005 < z < 0.03 using single-band and hybrid tracers. We provide updated calibrations, both global and split by properties (including stellar mass and morphological type), referred to H{\\alpha}. The extinction-corrected H{\\alpha} luminosity agrees with the updated hybrid SFR estimators based on either UV or H{\\alpha} plus IR luminosity over the...

  3. Improving Basic Skills in the Workplace. A Core Course for the Catering and Hospitality Industries.

    Science.gov (United States)

    Collins, Lorraine

    This training pack is designed for use with employees in the catering and hospitality industries. The material takes common workplace procedures and terminology and uses these as the basis for improving reading, writing, oral communication, and math skills. The pack is designed as a complete course of 13 modules over a period of 32-48 hours, but…

  4. Synthesis and characterization of mesoporous ZSM-5 core-shell particles for improved catalytic properties

    DEFF Research Database (Denmark)

    Kustova, Marina; Holm, Martin Spangsberg; Christensen, Claus H.

    2008-01-01

    HZSM-5 is a unique catalyst for the conversion of methanol, dimethyl ether and other oxygenates into gasoline. During this process, catalyst deactivation by coking requires frequent regeneration and the improvement of catalyst life time is one of the challenges in catalyst development...

  5. Superparamagnetic iron oxide/chitosan core/shells for hyperthermia application: Improved colloidal stability and biocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Patil, R.M.; Shete, P.B.; Thorat, N.D.; Otari, S.V. [Center for Interdisciplinary Research, D.Y. Patil University, Kolhapur 416006, MS (India); Barick, K.C.; Prasad, A.; Ningthoujam, R.S. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085, MS (India); Tiwale, B.M. [Center for Interdisciplinary Research, D.Y. Patil University, Kolhapur 416006, MS (India); Pawar, S.H., E-mail: pawar_s_h@yahoo.com [Center for Interdisciplinary Research, D.Y. Patil University, Kolhapur 416006, MS (India)

    2014-04-15

    Superparamagnetic magnetite nanoparticles are of great interest due to their potential biomedical applications. In the present investigation, Fe{sub 3}O{sub 4} magnetic nanoparticles were prepared by alkaline precipitation using ferrous chloride as the sole source. An amphiphilic polyelectrolyte with the property of biocompatibility and functional carboxyl groups was used as a stabilizer to prepare a well-dispersed suspension of superparamagnetic Fe{sub 3}O{sub 4} nanoparticles. The final material composed of Fe{sub 3}O{sub 4} core and chitosan (CH) shell was produced. The amino groups of CH coated on Fe{sub 3}O{sub 4} nanoparticles were further cross linked using glutaraldehyde (GLD) for stable coating. FTIR spectra, XPS and TGA confirmed the coating of CH/GLD on the surface of Fe{sub 3}O{sub 4} nanoparticles. XRD patterns indicate the pure phase Fe{sub 3}O{sub 4} with a spinel structure. The nanoparticles were superparamagnetic at room temperature with saturation magnetization values for bare and coated nanoparticles which were 51.68 emu/g and 48.60 emu/g, respectively. Zeta potential values showed higher colloidal stability of coated nanoparticles than the bare one. Cytotoxicity study up to 2 mg mL{sup −1} concentration showed no drastic change in cell viability of nanoparticles after coating. Also, coated nanoparticles showed increased SAR value, making them suitable for hyperthermia therapy application. - Highlights: • Fe{sub 3}O{sub 4} nanoparticles were synthesized from FeCl{sub 2} as the sole source by alkaline precipitation. • Coating of Fe{sub 3}O{sub 4} nanoparticles was done with chitosan by simple ultrasonication. • Chitosan cross-linked with glutaraldehyde. • High colloidal stability was observed. • Increased SAR value and least cytotoxicity were observed.

  6. Development of Core Heat Removal Objective Provision Trees for Sodium-Cooled Fast Reactor Defense-in-Depth Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Huichang; Kang, Bongsuk; Lee, Youngho [TUEV Rheinland Korea Ltd., Seoul (Korea, Republic of); Suh, Namduk [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2013-10-15

    Based on the definition of Defense-in-Depth levels and safety functions for KALIMER sodium-cooled fast reactor, suggested in the reference and, OPTs for level 1, 2, and 3 defense-in-depth and core heat removal safety function, were developed and suggested in this paper. The purpose of this OPT is first to assure the defensein-depth design during the licensing of Sodium-Cooled Fast Reactors (SFR), but it will also contribute in evaluating the completeness of regulatory requirements under development by Korea Institute of Nuclear Safety (KINS). The challenges and mechanisms and provisions were briefly explained in this paper. Comparing the mechanisms and provisions with the requirements will contribute in identifying the missing requirements. Since the design of PGSFR (Prototype Gen-IV SFR) is not mature yet, the OPT is developed for KALIMER design. Developed OPTs in this study can be used for the identification of potential design vulnerabilities. When detailed identification of provisions in terms of design features were achieved through the next step of this study, it can contribute to the establishment of defensein-depth evaluation frame for the regulatory reviews for the licensing process. At this moment, the identified provisions have both aspects as requirements and design features already adopted in KALIMER design. In the next stage of this study, derived provisions to be adopted will be compared with the actual design features and findings can be suggested as recommendations for the safety improvement.

  7. Models for dose assessments. Models adapted to the SFR-area, Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, Sara; Bergstroem, U.; Meili, M. [Studsvik Eco and Safety AB, Nykoeping (Sweden)

    2001-10-01

    This report presents a model system created to be used to predict dose rates to the most exposed individuals in case of a long-term release of radionuclides from the Final repository for radioactive operational waste (SFR) in Forsmark, Sweden. The system accounts for an underground point source emitting radionuclides to the biosphere,their transport and distribution in various ecosystem types, their uptake by various biota, and calculation of doses to man from a multitude of exposure pathways. Long-term aspects include the consideration of processes at geological time scales, such as land uplift and conversion of marine sediments to arable land. Model parameters are whenever possible based on local conditions and recent literature. The system has been used for simulations based on geospheric releases varying over time of a mixture of radionuclides. Here, the models have been subjected to various test scenarios, including different radionuclide entry points and sorption properties. Radionuclides released from SFR are efficiently diluted to low concentrations in the water of the coastal model. A large fraction of the nuclides leave the Model Area quickly as a consequence of the rapid water turnover. The total amount of radionuclides in water is about the same independent of particle affinity (K{sub d} ), and at most some percents of the amounts retained in the sediments for some time. The latter is also true for the lake model when releases of radionuclides to the water is simulated. The role of sediments as a radionuclide source seems of minor importance in lakes at least for long-term radiation doses. Modelling the sediments as a source of radionuclides most of the 'low K{sub d} radionuclides' will leave the lake whereas the 'high K{sub d} nuclides' are still present within the deeper sediments after 1 000 years. The amount of 'low K{sub d} radionuclides' present in the water and on suspended matter are about 8x10{sup -5} of the

  8. A Review of Models for Dose Assessment Employed by SKB in the Renewed Safety Assessment for SFR 1

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, George [Imperial College of Science Technology and Medicine (United Kingdom)

    2002-09-01

    This document provides a critical review, on behalf of SSI, of the models employed by the Swedish Nuclear Fuel and Waste Management Co (SKB) for dose assessment in the renewed safety assessment for the final repository for radioactive operational waste (SFR 1) in Forsmark, Sweden. The main objective of the review is to examine the models used by SKB for radiological dose assessment in a series of evolving biotopes in the vicinity of the Forsmark repository within a time frame beginning in 3000 AD and extending beyond 7500 AD. Five biosphere models (for coasts, lakes, agriculture, mires and wells) are described in Report TR-01-04. The principal consideration of the review is to determine whether these models are fit for the purpose of dose evaluation over the time frames involved and in the evolving sequence of biotopes specified. As well as providing general observations and comments on the modelling approach taken, six specific questions are addressed, as follows. Are the assumptions underlying the models justifiable? Are all reasonably foreseeable environmental processes considered? Has parameter uncertainty been sufficiently and reasonably addressed? Have sufficient models been used to address all reasonably foreseeable biotopes? Are the transitions between biotopes modelled adequately (specifically, are initial conditions for developing biotopes adequately specified by calculations for subsiding biotopes)? Have all critical radionuclides been identified? It is concluded that, in general, the assumptions underlying most of the models are justifiable. The exceptions are a) the rather simplistic approach taken in the Coastal Model and b) the lack of consideration of wild foods and age-dependence when calculating exposures of humans to radionuclides via dietary pathways. Most foreseeable processes appear to have been accounted for within the constraints of the models used, although it is recommended that attention be paid to future climate states when considering

  9. Improving PWR core simulations by Monte Carlo uncertainty analysis and Bayesian inference

    CERN Document Server

    Castro, Emilio; Buss, Oliver; Garcia-Herranz, Nuria; Hoefer, Axel; Porsch, Dieter

    2016-01-01

    A Monte Carlo-based Bayesian inference model is applied to the prediction of reactor operation parameters of a PWR nuclear power plant. In this non-perturbative framework, high-dimensional covariance information describing the uncertainty of microscopic nuclear data is combined with measured reactor operation data in order to provide statistically sound, well founded uncertainty estimates of integral parameters, such as the boron letdown curve and the burnup-dependent reactor power distribution. The performance of this methodology is assessed in a blind test approach, where we use measurements of a given reactor cycle to improve the prediction of the subsequent cycle. As it turns out, the resulting improvement of the prediction quality is impressive. In particular, the prediction uncertainty of the boron letdown curve, which is of utmost importance for the planning of the reactor cycle length, can be reduced by one order of magnitude by including the boron concentration measurement information of the previous...

  10. Defining core issues in utilizing information technology to improve access: evaluation and research agenda.

    Science.gov (United States)

    Jackson, George L; Krein, Sarah L; Alverson, Dale C; Darkins, Adam W; Gunnar, William; Harada, Nancy D; Helfrich, Christian D; Houston, Thomas K; Klobucar, Thomas F; Nazi, Kim M; Poropatich, Ronald K; Ralston, James D; Bosworth, Hayden B

    2011-11-01

    The Department of Veterans Affairs (VA) has been at the vanguard of information technology (IT) and use of comprehensive electronic health records. Despite the widespread use of health IT in the VA, there are still a variety of key questions that need to be answered in order to maximize the utility of IT to improve patient access to quality services. This paper summarizes the potential of IT to enhance healthcare access, key gaps in current evidence linking IT and access, and methodologic challenges for related research. We also highlight four key issues to be addressed when implementing and evaluating the impact of IT interventions on improving access to quality care: 1) Understanding broader needs/perceptions of the Veteran population and their caregivers regarding use of IT to access healthcare services and related information. 2) Understanding individual provider/clinician needs/perceptions regarding use of IT for patient access to healthcare. 3) System/Organizational issues within the VA and other organizations related to the use of IT to improve access. 4) IT integration and information flow with non-VA entities. While the VA is used as an example, the issues are salient for healthcare systems that are beginning to take advantage of IT solutions.

  11. Investigation of the Stress Intensity Limits of ASME Section III Div.5 for Structure Design Criteria of SFR Fuel Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Choo, Jin-Yup; Kim, Hyung-Kyu; Cheon, Jin-Sik [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    These affect the mechanical design of the fuel assembly components. And thus, appropriate structural design criteria should also be chosen to incorporate the specific design conditions of the SFR fuel assemblies. Among them, the temperature is one of the most crucial conditions to be concerned because the sodium coolant temperature is normally more than 500ºC which is much higher than that of the LWR (< 350ºC). This implies that a thermal creep should be significantly considered in the SFR fuel assembly mechanical design. In addition to the high temperature condition, an irradiation swelling is also an important behavior that the SFR fuel assembly material should accommodate. To incorporate the temperature and irradiation impacts, the material of the fuel assembly components is presently determined to be made of HT-9, the ferriticmartensitic steel. In this paper, the ASME Sec. III Div. 5 (referred to as ‘Div. 5’ hereinafter), which was developed for a ‘high temperature reactor’, is considered as one of the structural design criteria for the mechanical design of SFR fuel assemblies. In this paper, the stress intensity limits, S{sub m} and S{sub t} of HT-9 were built for the structural criteria of an SFR fuel assembly. S{sub m} is obtained from the ultimate strength. As for S{sub t}, it is more complicated because of its dependency of time duration in addition to temperature. Following the definition of S{sub mt}, the method in the ASME Sec. III Div. 1, Subsec. NH was consulted. We found that the Sm is adopted as S{sub mt} under the temperature about 470ºC which is relatively low temperature range and over 470ºC with relatively short time duration as 1000 hours. And the S{sub t} is adopted as Smt at over 470ºC and long time duration over 34800 hours, and over 520ºC and 10{sup 4} hours too. And at over 570ºC and 1000 hours, and at over 630ºC and 100 hours, S{sub t} is also adopted for S{sub mt}.

  12. An Improved Multipole Approximation for Self-gravity and Its Importance for Core-collapse Supernova Simulations

    Science.gov (United States)

    Couch, Sean M.; Graziani, Carlo; Flocke, Norbert

    2013-12-01

    Self-gravity computation by multipole expansion is a common approach in problems such as core-collapse and Type Ia supernovae, where single large condensations of mass must be treated. The standard formulation of multipole self-gravity in arbitrary coordinate systems suffers from two significant sources of error, which we correct in the formulation presented in this article. The first source of error is due to the numerical approximation that effectively places grid cell mass at the central point of the cell, then computes the gravitational potential at that point, resulting in a convergence failure of the multipole expansion. We describe a new scheme that avoids this problem by computing gravitational potential at cell faces. The second source of error is due to sub-optimal choice of location for the expansion center, which results in angular power at high multipole l values in the gravitational field, requiring a high—and expensive—value of multipole cutoff l max. By introducing a global measure of angular power in the gravitational field, we show that the optimal coordinate for the expansion is the square-density-weighted mean location. We subject our new multipole self-gravity algorithm, implemented in the FLASH simulation framework, to two rigorous test problems: MacLaurin spheroids for which exact analytic solutions are known, and core-collapse supernovae. We show that key observables of the core-collapse simulations, particularly shock expansion, proto-neutron star motion, and momentum conservation, are extremely sensitive to the accuracy of the multipole gravity, and the accuracy of their computation is greatly improved by our reformulated solver.

  13. Improved Solar-Driven Photocatalytic Performance of Highly Crystalline Hydrogenated TiO2 Nanofibers with Core-Shell Structure

    Science.gov (United States)

    Wu, Ming-Chung; Chen, Ching-Hsiang; Huang, Wei-Kang; Hsiao, Kai-Chi; Lin, Ting-Han; Chan, Shun-Hsiang; Wu, Po-Yeh; Lu, Chun-Fu; Chang, Yin-Hsuan; Lin, Tz-Feng; Hsu, Kai-Hsiang; Hsu, Jen-Fu; Lee, Kun-Mu; Shyue, Jing-Jong; Kordás, Krisztián; Su, Wei-Fang

    2017-01-01

    Hydrogenated titanium dioxide has attracted intensive research interests in pollutant removal applications due to its high photocatalytic activity. Herein, we demonstrate hydrogenated TiO2 nanofibers (H:TiO2 NFs) with a core-shell structure prepared by the hydrothermal synthesis and subsequent heat treatment in hydrogen flow. H:TiO2 NFs has excellent solar light absorption and photogenerated charge formation behavior as confirmed by optical absorbance, photo-Kelvin force probe microscopy and photoinduced charge carrier dynamics analyses. Photodegradation of various organic dyes such as methyl orange, rhodamine 6G and brilliant green is shown to take place with significantly higher rates on our novel catalyst than on pristine TiO2 nanofibers and commercial nanoparticle based photocatalytic materials, which is attributed to surface defects (oxygen vacancy and Ti3+ interstitial defect) on the hydrogen treated surface. We propose three properties/mechanisms responsible for the enhanced photocatalytic activity, which are: (1) improved absorbance allowing for increased exciton generation, (2) highly crystalline anatase TiO2 that promotes fast charge transport rate, and (3) decreased charge recombination caused by the nanoscopic Schottky junctions at the interface of pristine core and hydrogenated shell thus promoting long-life surface charges. The developed H:TiO2 NFs can be helpful for future high performance photocatalysts in environmental applications. PMID:28102314

  14. Improved Solar-Driven Photocatalytic Performance of Highly Crystalline Hydrogenated TiO2 Nanofibers with Core-Shell Structure.

    Science.gov (United States)

    Wu, Ming-Chung; Chen, Ching-Hsiang; Huang, Wei-Kang; Hsiao, Kai-Chi; Lin, Ting-Han; Chan, Shun-Hsiang; Wu, Po-Yeh; Lu, Chun-Fu; Chang, Yin-Hsuan; Lin, Tz-Feng; Hsu, Kai-Hsiang; Hsu, Jen-Fu; Lee, Kun-Mu; Shyue, Jing-Jong; Kordás, Krisztián; Su, Wei-Fang

    2017-01-19

    Hydrogenated titanium dioxide has attracted intensive research interests in pollutant removal applications due to its high photocatalytic activity. Herein, we demonstrate hydrogenated TiO2 nanofibers (H:TiO2 NFs) with a core-shell structure prepared by the hydrothermal synthesis and subsequent heat treatment in hydrogen flow. H:TiO2 NFs has excellent solar light absorption and photogenerated charge formation behavior as confirmed by optical absorbance, photo-Kelvin force probe microscopy and photoinduced charge carrier dynamics analyses. Photodegradation of various organic dyes such as methyl orange, rhodamine 6G and brilliant green is shown to take place with significantly higher rates on our novel catalyst than on pristine TiO2 nanofibers and commercial nanoparticle based photocatalytic materials, which is attributed to surface defects (oxygen vacancy and Ti(3+) interstitial defect) on the hydrogen treated surface. We propose three properties/mechanisms responsible for the enhanced photocatalytic activity, which are: (1) improved absorbance allowing for increased exciton generation, (2) highly crystalline anatase TiO2 that promotes fast charge transport rate, and (3) decreased charge recombination caused by the nanoscopic Schottky junctions at the interface of pristine core and hydrogenated shell thus promoting long-life surface charges. The developed H:TiO2 NFs can be helpful for future high performance photocatalysts in environmental applications.

  15. Improved Solar-Driven Photocatalytic Performance of Highly Crystalline Hydrogenated TiO2 Nanofibers with Core-Shell Structure

    Science.gov (United States)

    Wu, Ming-Chung; Chen, Ching-Hsiang; Huang, Wei-Kang; Hsiao, Kai-Chi; Lin, Ting-Han; Chan, Shun-Hsiang; Wu, Po-Yeh; Lu, Chun-Fu; Chang, Yin-Hsuan; Lin, Tz-Feng; Hsu, Kai-Hsiang; Hsu, Jen-Fu; Lee, Kun-Mu; Shyue, Jing-Jong; Kordás, Krisztián; Su, Wei-Fang

    2017-01-01

    Hydrogenated titanium dioxide has attracted intensive research interests in pollutant removal applications due to its high photocatalytic activity. Herein, we demonstrate hydrogenated TiO2 nanofibers (H:TiO2 NFs) with a core-shell structure prepared by the hydrothermal synthesis and subsequent heat treatment in hydrogen flow. H:TiO2 NFs has excellent solar light absorption and photogenerated charge formation behavior as confirmed by optical absorbance, photo-Kelvin force probe microscopy and photoinduced charge carrier dynamics analyses. Photodegradation of various organic dyes such as methyl orange, rhodamine 6G and brilliant green is shown to take place with significantly higher rates on our novel catalyst than on pristine TiO2 nanofibers and commercial nanoparticle based photocatalytic materials, which is attributed to surface defects (oxygen vacancy and Ti3+ interstitial defect) on the hydrogen treated surface. We propose three properties/mechanisms responsible for the enhanced photocatalytic activity, which are: (1) improved absorbance allowing for increased exciton generation, (2) highly crystalline anatase TiO2 that promotes fast charge transport rate, and (3) decreased charge recombination caused by the nanoscopic Schottky junctions at the interface of pristine core and hydrogenated shell thus promoting long-life surface charges. The developed H:TiO2 NFs can be helpful for future high performance photocatalysts in environmental applications.

  16. Mapping the average AGN accretion rate in the SFR-M* plane for Herschel-selected galaxies at 0 < z ≤ 2.5

    Science.gov (United States)

    Delvecchio, I.; Lutz, D.; Berta, S.; Rosario, D. J.; Zamorani, G.; Pozzi, F.; Gruppioni, C.; Vignali, C.; Brusa, M.; Cimatti, A.; Clements, D. L.; Cooray, A.; Farrah, D.; Lanzuisi, G.; Oliver, S.; Rodighiero, G.; Santini, P.; Symeonidis, M.

    2015-05-01

    We study the relation of AGN accretion, star formation rate (SFR) and stellar mass (M*) using a sample of ≈8600 star-forming galaxies up to z = 2.5 selected with Herschel imaging in the GOODS and COSMOS fields. For each of them we derive SFR and M*, both corrected, when necessary, for emission from an active galactic nucleus (AGN), through the decomposition of their spectral energy distributions (SEDs). About 10 per cent of the sample are detected individually in Chandra observations of the fields. For the rest of the sample, we stack the X-ray maps to get average X-ray properties. After subtracting the X-ray luminosity expected from star formation and correcting for nuclear obscuration, we derive the average AGN accretion rate for both detected sources and stacks, as a function of M*, SFR and redshift. The average accretion rate correlates with SFR and with M*. The dependence on SFR becomes progressively more significant at z > 0.8. This may suggest that SFR is the original driver of these correlations. We find that average AGN accretion and star formation increase in a similar fashion with offset from the star-forming `main-sequence'. Our interpretation is that accretion on to the central black hole and star formation broadly trace each other, irrespective of whether the galaxy is evolving steadily on the main-sequence or bursting.

  17. Mapping the average AGN accretion rate in the SFR-M* plane for Herschel selected galaxies at 0

    CERN Document Server

    Delvecchio, I; Berta, S; Rosario, D J; Zamorani, G; Pozzi, F; Gruppioni, C; Vignali, C; Brusa, M; Cimatti, A; Clements, D L; Cooray, A; Farrah, D; Lanzuisi, G; Oliver, S; Rodighiero, G; Santini, P; Symeonidis, M

    2015-01-01

    We study the relation of AGN accretion, star formation rate (SFR), and stellar mass (M$_*$) using a sample of $\\approx$ 8600 star-forming galaxies up to z=2.5 selected with \\textit{Herschel} imaging in the GOODS and COSMOS fields. For each of them we derive SFR and M$_*$, both corrected, when necessary, for emission from an active galactic nucleus (AGN), through the decomposition of their spectral energy distributions (SEDs). About 10 per cent of the sample are detected individually in \\textit{Chandra} observations of the fields. For the rest of the sample we stack the X-ray maps to get average X-ray properties. After subtracting the X-ray luminosity expected from star formation and correcting for nuclear obscuration, we derive the average AGN accretion rate for both detected sources and stacks, as a function of M$_{*}$, SFR and redshift. The average accretion rate correlates with SFR and with M$_*$. The dependence on SFR becomes progressively more significant at z$>$0.8. This may suggest that SFR is the orig...

  18. An Improved Technique for Measurement of Cold HI in Molecular Cloud Cores

    CERN Document Server

    Krco, Marko; Brown, Robert L; Li, Di

    2008-01-01

    The presence of atomic gas mixed with molecular species in a "molecular" cloud may significantly affect its chemistry, the excitation of some species, and can serve as probe of the cloud's evolution. Cold neutral atomic hydrogen (HI) in molecular clouds is revealed by its self absorption of background galactic HI 21-cm emission. The properties of this gas can be investigated quantitatively through observation of HI Narrow Self-Absorption (HINSA). In this paper, we present a new technique for measuring atomic gas physical parameters from HINSA observations that utilizes molecular tracers to guide the HINSA extraction. This technique offers a significant improvement in the precision with which HI column densities can be determined over previous methods, and it opens several new avenues of study of relevance to the field of star formation.

  19. Iterative image reconstruction algorithms in coronary CT angiography improve the detection of lipid-core plaque - a comparison with histology

    Energy Technology Data Exchange (ETDEWEB)

    Puchner, Stefan B. [Massachusetts General Hospital, Harvard Medical School, Cardiac MR PET CT Program, Department of Radiology, Boston, MA (United States); Medical University of Vienna, Department of Biomedical Imaging and Image-Guided Therapy, Vienna (Austria); Ferencik, Maros [Massachusetts General Hospital, Harvard Medical School, Cardiac MR PET CT Program, Department of Radiology, Boston, MA (United States); Harvard Medical School, Division of Cardiology, Massachusetts General Hospital, Boston, MA (United States); Maurovich-Horvat, Pal [Massachusetts General Hospital, Harvard Medical School, Cardiac MR PET CT Program, Department of Radiology, Boston, MA (United States); Semmelweis University, MTA-SE Lenduelet Cardiovascular Imaging Research Group, Heart and Vascular Center, Budapest (Hungary); Nakano, Masataka; Otsuka, Fumiyuki; Virmani, Renu [CV Path Institute Inc., Gaithersburg, MD (United States); Kauczor, Hans-Ulrich [University Hospital Heidelberg, Ruprecht-Karls-University of Heidelberg, Department of Diagnostic and Interventional Radiology, Heidelberg (Germany); Hoffmann, Udo [Massachusetts General Hospital, Harvard Medical School, Cardiac MR PET CT Program, Department of Radiology, Boston, MA (United States); Schlett, Christopher L. [Massachusetts General Hospital, Harvard Medical School, Cardiac MR PET CT Program, Department of Radiology, Boston, MA (United States); University Hospital Heidelberg, Ruprecht-Karls-University of Heidelberg, Department of Diagnostic and Interventional Radiology, Heidelberg (Germany)

    2015-01-15

    To evaluate whether iterative reconstruction algorithms improve the diagnostic accuracy of coronary CT angiography (CCTA) for detection of lipid-core plaque (LCP) compared to histology. CCTA and histological data were acquired from three ex vivo hearts. CCTA images were reconstructed using filtered back projection (FBP), adaptive-statistical (ASIR) and model-based (MBIR) iterative algorithms. Vessel cross-sections were co-registered between FBP/ASIR/MBIR and histology. Plaque area <60 HU was semiautomatically quantified in CCTA. LCP was defined by histology as fibroatheroma with a large lipid/necrotic core. Area under the curve (AUC) was derived from logistic regression analysis as a measure of diagnostic accuracy. Overall, 173 CCTA triplets (FBP/ASIR/MBIR) were co-registered with histology. LCP was present in 26 cross-sections. Average measured plaque area <60 HU was significantly larger in LCP compared to non-LCP cross-sections (mm{sup 2}: 5.78 ± 2.29 vs. 3.39 ± 1.68 FBP; 5.92 ± 1.87 vs. 3.43 ± 1.62 ASIR; 6.40 ± 1.55 vs. 3.49 ± 1.50 MBIR; all p < 0.0001). AUC for detecting LCP was 0.803/0.850/0.903 for FBP/ASIR/MBIR and was significantly higher for MBIR compared to FBP (p = 0.01). MBIR increased sensitivity for detection of LCP by CCTA. Plaque area <60 HU in CCTA was associated with LCP in histology regardless of the reconstruction algorithm. However, MBIR demonstrated higher accuracy for detecting LCP, which may improve vulnerable plaque detection by CCTA. (orig.)

  20. New sol–gel refractory coatings on chemically-bonded sand cores for foundry applications to improve casting surface quality

    DEFF Research Database (Denmark)

    Nwaogu, Ugochukwu Chibuzoh; Poulsen, T.; Stage, R.K.

    2011-01-01

    Foundry refractory coatings protect bonded sand cores and moulds from producing defective castings during the casting process by providing a barrier between the core and the liquid metal. In this study, new sol–gel refractory coating on phenolic urethane cold box (PUCB) core was examined....... The coating density, viscosity, moisture content and wet and dry weight of the coating were evaluated on cores that had been coated at three different dip-coating times. The coating coverage, surface appearance and depth of penetration into the cores were examined with a Stereomicroscope. Gray iron castings...... were produced with sol-gel coated and uncoated cores and the results were related to the coating properties. The casting results were also compared with castings made with cores coated with commercial alcohol-based and water-based foundry coatings. The analyses show that castings produced with sol...

  1. The impact of the Star Formation Histories on the SFR-M$_{*}$ relation at z$\\ge$2

    CERN Document Server

    Cassarà, L P; Garilli, B; Scodeggio, M; Thomas, R; Fèvre, O Le; Zamorani, G; Schaerer, D; Lemaux, B C; Cassata, P; Brun, V Le; Pentericci, L; Tasca, L A M; Vanzella, E; Zucca, E; Amorín, R; Bardelli, S; Castellano, M; Cimatti, A; Cucciati, O; Durkalec, A; Fontana, A; Giavalisco, M; Grazian, A; Hathi, N P; Ilbert, O; Paltani, S; Ribeiro, B; Sommariva, V; Talia, M; Tresse, L; Vergani, D; Capak, P; Charlot, S; Contini, T; de la Torre, S; Dunlop, J; Fotopoulou, S; Guaita, L; Koekemoer, A; López-Sanjuan, C; Mellier, Y; Pforr, J; Salvato, M; Scoville, N; Taniguchi, Y; Wang, P W

    2016-01-01

    In this paper we investigate the impact of different star formation histories (SFHs) on the relation between stellar mass M$_{*}$ and star formation rate (SFR) using a sample of galaxies with reliable spectroscopic redshift zspec>2 drawn from the VIMOS Ultra-Deep Survey (VUDS). We produce an extensive database of dusty model galaxies, calculated starting from the new library of single stellar population (SSPs) models presented in Cassara' et al. 2013 and weighted by a set of 28 different SFHs based on the Schmidt function, and characterized by different ratios of the gas infall time scale $\\tau_{infall}$ to the star formation efficiency $\

  2. One-Dimensional Analysis of Thermal Stratification in AHTR and SFR Coolant Pools

    Energy Technology Data Exchange (ETDEWEB)

    Haihua Zhao; Per F. Peterson

    2007-10-01

    Thermal stratification phenomena are very common in pool type reactor systems, such as the liquid-salt cooled Advanced High Temperature Reactor (AHTR) and liquid-metal cooled fast reactor systems such as the Sodium Fast Reactor (SFR). It is important to accurately predict the temperature and density distributions both for design optimation and accident analysis. Current major reactor system analysis codes such as RELAP5 (for LWR’s, and recently extended to analyze high temperature reactors), TRAC (for LWR’s), and SASSYS (for liquid metal fast reactors) only provide lumped-volume based models which can only give very approximate results and can only handle simple cases with one mixing source. While 2-D or 3-D CFD methods can be used to analyze simple configurations, these methods require very fine grid resolution to resolve thin substructures such as jets and wall boundaries, yet such fine grid resolution is difficult or impossible to provide for studying the reactor response to transients due to computational expense. Therefore, new methods are needed to support design optimization and safety analysis of Generation IV pool type reactor systems. Previous scaling has shown that stratified mixing processes in large stably stratified enclosures can be described using one-dimensional differential equations, with the vertical transport by free and wall jets modeled using standard integral techniques. This allows very large reductions in computational effort compared to three-dimensional numerical modeling of turbulent mixing in large enclosures. The BMIX++ (Berkeley mechanistic MIXing code in C++) code was originally developed at UC Berkeley to implement such ideas. This code solves mixing and heat transfer problems in stably stratified enclosures. The code uses a Lagrangian approach to solve 1-D transient governing equations for the ambient fluid and uses analytical or 1-D integral models to compute substructures. By including liquid salt properties, BMIX++ code is

  3. Enhanced exchange bias and improved ferromagnetic properties in Permalloy-BiFe0.95Co0.05O3 core-shell nanostructures

    Science.gov (United States)

    Javed, K.; Li, W. J.; Ali, S. S.; Shi, D. W.; Khan, U.; Riaz, S.; Han, X. F.

    2015-12-01

    Hybrid core-shell nanostructures consisting of permalloy (Ni80Fe20) and multiferroic(BiFeO3, BFO/BiFe0.95Co0.05O3, BFC) materials were synthesized by a two-step method, based on wet chemical impregnation and subsequent electrodeposition within porous alumina membranes. Structural and magnetic characterizations have been done to investigate doping effect on magnetic properties and exchange bias. The magnetometry analysis revealed significant enhancements of the exchange bias and coercivity in NiFe-BFC core-shell nanostructures as compared with NiFe-BFO core-shell nanostructures. The enhancements can be attributed to the effective reduction of ferromagnet domain sizes between adjacent layers of core-shell structure. It indicates that it is possible to improve properties of multiferroic composites by site-engineering method. Our approach opens a pathway to obtain optimized nanostructured multiferroic composites exhibiting tunable magnetic properties.

  4. Core-Shell Soy Protein-Soy Polysaccharide Complex (Nano)particles as Carriers for Improved Stability and Sustained Release of Curcumin.

    Science.gov (United States)

    Chen, Fei-Ping; Ou, Shi-Yi; Tang, Chuan-He

    2016-06-22

    Using soy protein isolate (SPI) and soy-soluble polysaccharides (SSPS) as polymer matrixes, this study reported a novel process to fabricate unique core-shell complex (nano)particles to perform as carriers for curcumin (a typical poorly soluble bioactive). In the process, curcumin-SPI nanocomplexes were first formed at pH 7.0 and then coated by SSPS. At this pH, the core-shell complex was formed in a way the SPI nanoparticles might be incorporated into the interior of SSPS molecules without distinctly affecting the size and morphology of particles. The core-shell structure was distinctly changed by adjusting pH from 7.0 to 4.0. At pH 4.0, SSPS was strongly bound to the surface of highly aggregated SPI nanoparticles, and as a consequence, much larger complexes were formed. The bioaccessibility of curcumin in the SPI-curcumin complexes was unaffected by the SSPS coating. However, the core-shell complex formation greatly improved the thermal stability and controlled release properties of encapsulated curcumin. The improvement was much better at pH 4.0 than that at pH 7.0. All of the freeze-dried core-shell complex preparations exhibited good redispersion behavior. The findings provide a simple approach to fabricate food-grade delivery systems for improved water dispersion, heat stability, and even controlled release of poorly soluble bioactives.

  5. Incorporating trnH-psbA to the core DNA barcodes improves significantly species discrimination within southern African Combretaceae

    Directory of Open Access Journals (Sweden)

    Jephris Gere

    2013-12-01

    Full Text Available Recent studies indicate that the discriminatory power of the core DNA barcodes (rbcLa + matK for land plants may have been overestimated since their performance have been tested only on few closely related species. In this study we focused mainly on how the addition of complementary barcodes (nrITS and trnH-psbA to the core barcodes will affect the performance of the core barcodes in discriminating closely related species from family to section levels. In general, we found that the core barcodes performed poorly compared to the various combinations tested. Using multiple criteria, we finally advocated for the use of the core + trnH-psbA as potential DNA barcode for the family Combretaceae at least in southern Africa. Our results also indicate that the success of DNA barcoding in discriminating closely related species may be related to evolutionary and possibly the biogeographic histories of the taxonomic group tested.

  6. Does core stability exercise improve lumbopelvic stability (through endurance tests) more than general exercise in chronic low back pain? A quasi-randomized controlled trial.

    Science.gov (United States)

    Shamsi, Mohammad Bagher; Rezaei, Mandana; Zamanlou, Mehdi; Sadeghi, Mehdi; Pourahmadi, Mohammad Reza

    2016-01-01

    The aim was to compare core stability and general exercises (GEs) in chronic low back pain (LBP) patients based on lumbopelvic stability (LPS) assessment through three endurance core stability tests. There is a controversy about preference of core stability exercise (CSE) over other types of exercise for chronic LBP. Studies which have compared these exercises used other outcomes than those related to LPS. As it is claimed that CSE enhances back stability, endurance tests for LPS were used. A 16-session CSE program and a GE program with the same duration were conducted for two groups of participants. Frequency of interventions for both groups was three times a week. Forty-three people (aged 18-60 years) with chronic non-specific LBP were alternately allocated to core stability (n = 22) or GE group (n = 21) when admitted. The primary outcomes were three endurance core stability tests including: (1) trunk flexor; (2) trunk extensor; and (3) side bridge tests. Secondary outcomes were disability and pain. Measurements were taken at baseline and the end of the intervention. After the intervention, test times increased and disability and pain decreased within groups. There was no significant difference between two groups in increasing test times (p = 0.23 to p = 0.36) or decreasing disability (p = 0.16) and pain (p = 0.73). CSE is not more effective than GE for improving endurance core stability tests and reducing disability and pain in chronic non-specific LBP patients.

  7. Evaluation for Core Competence of Private Enterprises in Xuchang City Based on an Improved Dynamic Multiple-Attribute Decision-Making Model

    OpenAIRE

    Jian-min Shen; Yao-guo Dang; Wei-jie Zhou; Xue-mei Li

    2015-01-01

    Because Deng’s grey relational degree is inconspicuous, Deng’s relational degree with an exponential function is first presented. Then, we demonstrate that improved Deng’s relational degree is more conspicuous than the original model. Then, we construct a multiple-attribute decision-making model, based on improved Deng’s relational degree with multiple stages, and a method for determining the weight of the index is also developed. Finally, the core competence of private enterprises in Henan p...

  8. Analyses of Design Extended Condition Events for the Prototype Gen-IV SFR

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chiwoong; Jeong, Taekyung; Lee, Kwilim; Jeong, Jaeho; Ha, Kwiseok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    In this study, the sensitivity tests are conducted. In the case of the UTOP event, a sensitivity test for the reactivity insertion amount and rate were conducted. This analysis can give a requirement for margin of control rod stop system (CRSS). For example, the CRSS in the PRISM designed based on the 0.4 $ reactivity insertion, which is analyzed with safety analysis of UTOP event. Moreover, the sensitivity tests for weighting factor in the core radial expansion reactivity feedback model were also carried out for all ATWS events. Currently, the reactivity feedback model for the PGSFR is not validated yet. However, the reactivity feedback models in the MARS-LMR are validating with various plant-based data including EBR-II SHRT. The ATWS events for the PGSFR classified in the design extended condition including UTOP, ULOF, and ULOHS are analyzed with MARS-LMR. In this study, the sensitivity tests for reactivity insertion amount and rate in the UTOP event are conducted. The reactivity insertion amount is obviously an influential parameter. The reactivity insertion amount can give a requirement for design of the CRSS, therefore, this sensitivity result is very important to the CRSS. In addition, sensitivity tests for the weighting factor in the radial expansion reactivity model are carried out. The weighting factor for a grid plate, W{sub GP}, which means contribution of feedback in the grid plate is changed for all unprotected events. The grid plate expansion is governed by a core inlet temperature. As the W{sub GP} is increased, the power in the UTOP and the ULOF is increased, however, the power in the ULOHS is decreased. The higher power during transient means lower reactivity feedback and smaller expansion. Thus, the core outlet temperature rise is dominant in the UTOP and ULOF events, however, the core inlet temperature rise is dominant in the ULOHS. Therefore, the grid plate expansion in the ULOHS is predominant.

  9. Effectiveness of core muscle strengthening for improving pain and dynamic balance among female patients with patellofemoral pain syndrome

    OpenAIRE

    2016-01-01

    [Purpose] Patellofemoral pain syndrome is a frequent musculoskeletal disorder, which can result from core muscles instability that can lead to pain and altered dynamic balance. The objective of this study is to assess the effect of core muscle strengthening on pain and dynamic balance in female patients with patellofemoral pain syndrome. [Subjects and Methods] Twenty female patients with age ranging from 16 to 40 years with patellofemoral pain syndrome were divided into study (N=10) and contr...

  10. Kinetic parameters study based on burn-up for improving the performance of research reactor equilibrium core

    Directory of Open Access Journals (Sweden)

    Muhammad Atta

    2014-01-01

    Full Text Available In this study kinetic parameters, effective delayed neutron fraction and prompt neutron generation time have been investigated at different burn-up stages for research reactor's equilibrium core utilizing low enriched uranium high density fuel (U3Si2-Al fuel with 4.8 g/cm3 of uranium. Results have been compared with reference operating core of Pakistan research Reactor-1. It was observed that by increasing fuel burn-up, effective delayed neutron fraction is decreased while prompt neutron generation time is increased. However, over all ratio beff/L is decreased with increasing burn-up. Prompt neutron generation time L in the understudy core is lower than reference operating core of reactor at all burn-up steps due to hard spectrum. It is observed that beff is larger in the understudy core than reference operating core of due to smaller size. Calculations were performed with the help of computer codes WIMSD/4 and CITATION.

  11. Improvement of the Cubic Spline Function Sets for a Synthesis of the Axial Power Distribution of a Core Protection System

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Bon-Seung; Lee, Chung-Chan; Zee, Sung-Quun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2006-07-01

    Online digital core protection system(SCOPS) for a system-integrated modular reactor is being developed as a part of a plant protection system at KAERI. SCOPS calculates the minimum CHFR and maximum LPD based on several online measured system parameters including 3-level ex-core detector signals. In conventional ABB-CE digital power plants, cubic spline synthesis technique has been used in online calculations of the core axial power distributions using ex-core detector signals once every 1 second in CPC. In CPC, pre-determined cubic spline function sets are used depending on the characteristics of the ex-core detector responses. But this method shows an unnegligible power distribution error for the extremely skewed axial shapes by using restrictive function sets. Therefore, this paper describes the cubic spline method for the synthesis of an axial power distribution and it generates several new cubic spline function sets for the application of the core protection system, especially for the severely distorted power shapes needed reactor type.

  12. KALIMER-600-clad Core Fuel Assembly Calculation using MATRA-LMR (V2.0) Code

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Gyun; Kim, Young Il

    2006-12-15

    Since the sodium boiling point is very high, maximum cladding and pin temperatures are used for design limit condition in sodium cooled liquid metal reactor. It is necessary to predict accurately the temperature distribution in the core and in the subassemblies to increase the sodium coolant efficiency. Based on the MATRA code, which is developed for PWR analysis, MATRA-LMR has been developed for SFR. The major modifications are: the sodium properties table is implemented as subprogram in the code, Heat transfer coefficients are changed for SFR, te pressure drop correlations are changed for more accurate calculations, which are Novendstern, Chiu-Rohsenow-Todreas, and Cheng-Todreas correlations. This This report describes briefly code structure and equations of MATRA-LMR (Version 2.0), explains input data preparation and shows some calculation results for the KALIMER-600-clad core fuel assembly for which has been performed the conceptual design of the core in the year 2006.

  13. Thermal hydraulic parametric investigation of decay heat removal from degraded core of a sodium cooled fast Breeder reactor

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Lokesh [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Kumar Sharma, Anil, E-mail: aksharma@igcar.gov.in [Reactor Design Group, Indira Gandhi Centre for Atomic Research, HBNI, Kalpakkam (India); Velusamy, K. [Reactor Design Group, Indira Gandhi Centre for Atomic Research, HBNI, Kalpakkam (India)

    2017-03-15

    Highlights: • Decay heat removal from degraded core of a typical SFR is highlighted. • Influence of number of DHXs in operation on PAHR is analyzed. • Investigations on structural integrity of the inner vessel and core catcher. • Feasibility study for retention of a part of debris in upper pool of SFR. - Abstract: Ensuring post accident decay heat removal with high degree of reliability following a Core Disruptive Accident (CDA) is very important in the design of sodium cooled fast reactors (SFR). In the recent past, a lot of research has been done towards the design of an in-vessel core catcher below the grid plate to prevent the core debris reaching the main vessel in a pool type SFR. However, during an energetic CDA, the entire core debris is unlikely to reach the core catcher. A significant part of the debris is likely to settle in core periphery between radial shielding subassemblies and the inner vessel. Failure of inner vessel due to the decay heat can lead to core debris reaching the main vessel and threatening its integrity. On the other hand, retention of a part of debris in core periphery can reduce the load on main core catcher. Towards achieving an optimum design of SFR and safety evaluation, it is essential to quantify the amount of heat generating core debris that can be retained safely within the primary vessel. This has been performed by a mathematical simulation comprising solution of 2-D transient form of the governing equations of turbulent sodium flow and heat transfer with Boussinesq approximations. The conjugate conduction-convection model adopted for this purpose is validated against in-house experimental data. Transient evolutions of natural convection in the pools and structural temperatures in critical components have been predicted. It is found that 50% of the core debris can be safely accommodated in the gap between radial shielding subassemblies and inner vessel without exceeding structural temperature limit. It is also

  14. Dithranol-loaded lipid-core nanocapsules improve the photostability and reduce the in vitro irritation potential of this drug

    Energy Technology Data Exchange (ETDEWEB)

    Savian, Ana L. [Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal de Santa Maria, Av. Roraima, 1000, Santa Maria, RS 97105-900 (Brazil); Rodrigues, Daiane [Curso de Farmácia, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Av. Roraima, 1000, Santa Maria, RS 97105-900 (Brazil); Weber, Julia; Ribeiro, Roseane F. [Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal de Santa Maria, Av. Roraima, 1000, Santa Maria, RS 97105-900 (Brazil); Motta, Mariana H. [Curso de Farmácia, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Av. Roraima, 1000, Santa Maria, RS 97105-900 (Brazil); Schaffazick, Scheila R.; Adams, Andréa I.H. [Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal de Santa Maria, Av. Roraima, 1000, Santa Maria, RS 97105-900 (Brazil); Andrade, Diego F. de; Beck, Ruy C.R. [Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal do Rio Grande do Sul, Av. Ipiranga, 2752, Porto Alegre, RS 90610-000 (Brazil); and others

    2015-01-01

    Dithranol is a very effective drug for the topical treatment of psoriasis. However, it has some adverse effects such as irritation and stain in the skin that make its application and patient adherence to treatment difficult. The aims of this work were to prepare and characterize dithranol-loaded nanocapsules as well as to evaluate the photostability and the irritation potential of these nanocarriers. Lipid-core nanocapsules containing dithranol (0.5 mg/mL) were prepared by interfacial deposition of preformed polymer. EDTA (0.05%) or ascorbic acid (0.02%) was used as antioxidants. After preparation, dithranol-loaded lipid-core nanocapsules showed satisfactory characteristics: drug content close to the theoretical concentration, encapsulation efficiency of about 100%, nanometric mean size (230–250 nm), polydispersity index below 0.25, negative zeta potential, and pH values from 4.3 to 5.6. In the photodegradation study against UVA light, we observed a higher stability of the dithranol-loaded lipid-core nanocapsules comparing to the solution containing the free drug (half-life times around 4 and 1 h for the dithranol-loaded lipid-core nanocapsules and free drug solution containing EDTA, respectively; half-life times around 17 and 7 h for the dithranol-loaded lipid-core nanocapsules and free drug solution containing ascorbic acid, respectively). Irritation test by HET-CAM method was conducted to evaluate the safety of the formulations. From the results it was found that the nanoencapsulation of the drug decreased its toxicity compared to the effects observed for the free drug. - Highlights: • Strategy to prepare lipid-core nanocapsules containing dithranol • Evaluation of the nanoencapsulation effect on the photostability and irritation • Evaluation of the in vitro release of dithranol-loaded lipid-core nanocapsules.

  15. Improved stratigraphic dating at a low accumulation Alpine ice core through laser ablation trace element profiling at sub-mm depth resolution

    Science.gov (United States)

    Bohleber, Pascal; Spaulding, Nicole; Mayewski, Paul; Sneed, Sharon; Handley, Mike; Erhardt, Tobias; Wagenbach, Dietmar

    2015-04-01

    The small scale Colle Gnifetti glacier saddle (4450 m asl, Monte Rosa region) is the only ice core drilling site in the European Alps with a net accumulation low enough to offer multi-millennia climate records. However, a robust interpretation of such long term records (i.e. mineral dust, stable water isotopes) at the Colle Gnifetti (CG) multi core array is strongly challenged by depositional noise associated with a highly irregular annual layer stratigraphy. In combination with a relatively large vertical strain rate and rapid layer thinning, annual layer counting gets increasingly ambiguous as of approximately 100 years. In addition, this prevents clear attribution of likely volcanic horizons to historical eruption dates. To improve stratigraphic dating under such intricate conditions, we deployed laser ablation (LA) ICP-MS at sub-mm sample resolution. We present here the first LA impurity profiles from a new Colle Gnifetti ice core drilled 73 m to bedrock in 2013 at a site where the net snow accumulation is around 20 cm w.e. per year. We contrast the LA signal variability (including Ca, Fe, Na) to continuous flow analyses (CFA) records at cm-resolution (Ca, Na, melt water conductivity, micro- particle) recorded over the whole core length. Of special concern are the lower 28 m to bedrock, which have been continuously profiled in LA Ca, thus offering the direct comparison of Ca-signals between CFA and LA. By this means, we first validate at upper depths LA based annual layer identification through agreement with CFA based counting efforts before demonstrating the LA based counting still works at depths where CFA derived annual layers become spurious since embedded in strong, multi-year cycles. Finally, LA ice core profiling of our CG core has potential for not only dating improvement but also reveals benefits in resolving highly thinned basal ice sections including accounting for micro-structural features such as grain boundaries.

  16. Electromagnet Response Time Tests on Primary CRDM of a Prototype Gen-IV SFR

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae-Han; Koo, Gyeong-Hoi [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    This paper identifies the electromagnetic response characteristics of the electromagnet of a primary control rod drive mechanism (CRDM) used for the reactor scram function. The test measures the electromagnet response time required to release an armature from a stator controlled by a loss of an electromagnetic force on an armature after shorting a power supply to an electromagnet coil. These tests are carried out while changing the electromagnet core material, an assist spring, and an armature holding current. The main factors influencing the test parameters on the response are found to be the armature holding current for holding the armature loads, and the material type of the electromagnet cores. The minimum response time is 0.13 seconds in the case of using SS410 material as an armature, while the S10C material as an armature has a response time of 0.21 seconds. Electromagnet response time characteristics from the test results will be evaluated by comparing the precise moving data of an electromagnet armature through the use of a high-speed camera and a potentiometer in the future.

  17. Evaluation for Core Competence of Private Enterprises in Xuchang City Based on an Improved Dynamic Multiple-Attribute Decision-Making Model

    Directory of Open Access Journals (Sweden)

    Jian-min Shen

    2015-01-01

    Full Text Available Because Deng’s grey relational degree is inconspicuous, Deng’s relational degree with an exponential function is first presented. Then, we demonstrate that improved Deng’s relational degree is more conspicuous than the original model. Then, we construct a multiple-attribute decision-making model, based on improved Deng’s relational degree with multiple stages, and a method for determining the weight of the index is also developed. Finally, the core competence of private enterprises in Henan province is analyzed, illustrating the validity and feasibility of the improved model.

  18. Core stability exercise is as effective as task-oriented motor training in improving motor proficiency in children with developmental coordination disorder: a randomized controlled pilot study.

    Science.gov (United States)

    Au, Mei K; Chan, Wai M; Lee, Lin; Chen, Tracy Mk; Chau, Rosanna Mw; Pang, Marco Yc

    2014-10-01

    To compare the effectiveness of a core stability program with a task-oriented motor training program in improving motor proficiency in children with developmental coordination disorder (DCD). Randomized controlled pilot trial. Outpatient unit in a hospital. Twenty-two children diagnosed with DCD aged 6-9 years were randomly allocated to the core stability program or the task-oriented motor program. Both groups underwent their respective face-to-face training session once per week for eight consecutive weeks. They were also instructed to carry out home exercises on a daily basis during the intervention period. Short Form of the Bruininks-Oseretsky Test of Motor Proficiency (Second Edition) and Sensory Organization Test at pre- and post-intervention. Intention-to-treat analysis revealed no significant between-group difference in the change of motor proficiency standard score (P=0.717), and composite equilibrium score derived from the Sensory Organization Test (P=0.100). Further analysis showed significant improvement in motor proficiency in both the core stability (mean change (SD)=6.3(5.4); p=0.008) and task-oriented training groups (mean change(SD)=5.1(4.0); P=0.007). The composite equilibrium score was significantly increased in the task-oriented training group (mean change (SD)=6.0(5.5); P=0.009), but not in the core stability group (mean change(SD) =0.0(9.6); P=0.812). In the task-oriented training group, compliance with the home program was positively correlated with change in motor proficiency (ρ=0.680, P=0.030) and composite equilibrium score (ρ=0.638, P=0.047). The core stability exercise program is as effective as task-oriented training in improving motor proficiency among children with DCD. © The Author(s) 2014.

  19. Sensitivity Tests for the Unprotected Events of the Prototype Gen-IV SFR

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chiwoong; Lee, Kwilim; Jeong, Jaeho; Yu, Jin; An, Sangjun; Lee, Seung Won; Chang, Wonpyo; Ha, Kwiseok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    Unprotected Transient Over Power, (UTOP), Unprotected Loss Of Flow (ULOF), and Unprotected Loss Of Heat Sink (ULOHS) are selected as ATWS events. Among these accidents, the ULOF event shows the lowest clad temperature. However, the ULOHS event showed the highest peak clad temperature, due to the positive CRDL/RV expansion reactivity feedback and insufficient DHRS capacity. In this study, the sensitivity tests are conducted. In the case of the UTOP event, a sensitivity test for the reactivity insertion amount and rate were conducted. This analysis can give a requirement for margin of control rod stop system (CRSS). Currently, the reactivity feedback model for the PGSFR is not validated yet. However, the reactivity feedback models in the MARS-LMR are validating with various plant-based data including EBR-II SHRT. The ATWS events for the PGSFR classified in the design extended condition including UTOP, ULOF, and ULOHS are analyzed with MARS-LMR. In this study, the sensitivity tests for reactivity insertion amount and rate in the UTOP event are conducted. The reactivity insertion amount is obviously an influential parameter. The reactivity insertion amount can give a requirement for design of the CRSS, therefore, this sensitivity result is very important to the CRSS. In addition, sensitivity tests for the weighting factor in the radial expansion reactivity model are carried out. The weighting factor for a grid plate, W{sub GP}, which means contribution of feedback in the grid plate is changed for all unprotected events. The grid plate expansion is governed by a core inlet temperature. As the W{sub GP} is increased, the power in the UTOP and the ULOF is increased, however, the power in the ULOHS is decreased. The higher power during transient means lower reactivity feedback and smaller expansion. Thus, the core outlet temperature rise is dominant in the UTOP and ULOF events, however, the core inlet temperature rise is dominant in the ULOHS. Therefore, the grid plate

  20. Facile fabrication of hierarchical ZnCo2O4/NiO core/shell nanowire arrays with improved lithium-ion battery performance.

    Science.gov (United States)

    Sun, Zhipeng; Ai, Wei; Liu, Jilei; Qi, Xiaoying; Wang, Yanlong; Zhu, Jianhui; Zhang, Hua; Yu, Ting

    2014-06-21

    We report a facile and controllable strategy for the fabrication of three-dimensional (3D) ZnCo2O4/NiO core/shell nanowire arrays (ZCO/NiO NWs) on nickel (Ni) foam substrates by a simple, cost-effective, two-step, solution-based method. Ultra-thin NiO nanosheets are revealed to grow uniformly on the porous ZnCo2O4 nanowires with many interparticle mesopores, resulting in the formation of 3D core/shell nanowire arrays with hierarchical architecture. In comparison with the pristine ZnCo2O4 nanowire arrays (ZCO NWs), the ZCO/NiO NWs exhibit significantly improved Li storage properties, in terms of higher capacity, enhanced rate capability and improved cycling stability when applied as binders and additive-free anode materials for lithium-ion batteries. The superior Li storage performance of the ZCO/NiO NWs could be attributed to the synergetic effect between the ZnCo2O4 core and the NiO shell, as well as its unique hierarchical architecture, which ensures a large specific surface area and good conductivity. Our results may offer very useful guidelines in scrupulously designing 3D core/shell nanowire-array electrodes using cheap, earth-abundant materials in energy storage applications.

  1. Short-term variations in core surface flow resolved from an improved method of calculating observatory monthly means

    DEFF Research Database (Denmark)

    Olsen, Nils; Whaler, K. A.; Finlay, Chris

    2014-01-01

    Monthly means of the magnetic field measurements taken by ground observatories are a useful data source for studying temporal changes of the core magnetic field and the underlying core flow. However, the usual way of calculating monthly means as the arithmetic mean of all days (geomagnetic quiet...... as well as disturbed) and all local times (day and night) may result in contributions from external (magnetospheric and ionospheric) origin in the (ordinary, omm) monthly means. Such contamination makes monthly means less favourable for core studies. We calculated revised monthly means (rmm...... a secular variation spherical harmonic model. The main field is specified by the CHAOS-4 model. Data from up to 128 observatories between 1997 and 2013 were used to calculate 185 flow models from the omm and rmm, for each possible set of three consecutive months. The full 3x3 (non-diagonal) data covariance...

  2. Improved microbial growth inhibition activity of bio-surfactant induced Ag–TiO{sub 2} core shell nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Nithyadevi, D. [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641 046 (India); Kumar, P. Suresh [Thin Film and Nanomaterials Laboratory, Department of Physics, Bharathiar University, Coimbatore 641 046 (India); Mangalaraj, D., E-mail: dmraj800@yahoo.com [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641 046 (India); Ponpandian, N.; Viswanathan, C. [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641 046 (India); Meena, P. [Department of Physics, PSGR Krishnammal college for women, Coimbatore 641 004 (India)

    2015-02-01

    Graphical abstract: - Highlights: • TiO{sub 2} nanoparticles were synthesized by hydrolysis process and Ag nanoparticles were prepared by using hydrazine reduction method. • Ag–TiO{sub 2} core shell nanoparticles were synthesized by reverse micelle method. • Coatings of TiO{sub 2} shell leads to decrease the usage of silver particles and also it reduces the release of silver ions from the matrix. • Optimum ratio of TiO{sub 2} particles: Ag atoms are needed for better antibacterial activity. • Sodium alginate (Bio-copolymer) induced core shell nanoparticles results 100% cell growth inhibition toward Staphylococcus aureus. - Abstract: Surfactant induced silver–titanium dioxide core shell nanoparticles within the size range of 10–50 nm were applied in the antibacterial agent to inhibit the growth of bacterial cells. The single crystalline silver was located in the core part of the composite powder and the titanium dioxide components were uniformly distributed in the shell part. HRTEM and XRD results indicated that silver was completely covered by titanium dioxide and its crystal structure was not affected after being coated by titanium dioxide. The effect of silver–titanium dioxide nanoparticles in the inhibition of bacterial cell growth was studied by means of disk diffusion method. The inhibition zone results reveal that sodium alginate induced silver–titanium dioxide nanoparticles exhibit 100% more antibacterial activity than that with cetyltrimethylbromide or without surfactant. UV–vis spectroscopic analysis showed a large concentration of silver was rapidly released into phosphate buffer solution (PBS) within a period of 1 day, with a much smaller concentration being released after this 1-day period. It was concluded that sodium alginate induced silver–titanium dioxide core shell nanoparticles could enhance long term cell growth inhibition in comparison with cetyltrimethylbromide or without surfactant. The surfactant mediated core shell

  3. Improve Human Resources Management to Enhance Core Competitiveness Hospital%提高人力资源管理水平增强医院核心竞争力

    Institute of Scientific and Technical Information of China (English)

    朱娟娟; 赵长伟

    2015-01-01

    Human resource management is the core competitiveness of the hospital. Therefore, the hospital must select the outstanding talent, establish a reasonable talent team, improve the level of human resources management. This paper dis-cusses the problem of improving the level of human resource management and enhancing the core competitiveness of the hospital from the two aspects of the concept and management mechanism.%人力资源管理是医院核心竞争力的根本。因此医院必须选取优秀的人才,建立合理的人才团队,提高人力资源管理水平。该文从用人理念、管理机制两方面,就提高人力资源管理水平、增强医院核心竞争力这一问题进行探讨。

  4. Examining the Effects of a National League for Nursing Core Competencies Workshop as an Intervention to Improve Nurse Faculty Practice

    Science.gov (United States)

    VanBever Wilson, Robin R.

    2010-01-01

    Due to the complex challenges facing schools of nursing, a research study was implemented to introduce nurse faculty at one small rural northeastern Tennessee school of nursing to the NLN "Core Competencies for Nurse Educators". Utilizing Kalb's Nurse Faculty Self-Evaluation Tool as a pre- and post-intervention test, 30 nurse faculty…

  5. Development of a core collection of Triticum and Aegilops species for improvement of wheat for activity against chronic diseases

    Directory of Open Access Journals (Sweden)

    Santra Meenakshi

    2013-02-01

    Full Text Available Abstract Background The objective of this study was to develop a core collection of Triticum and Aegilops species as a resource for the identification and characterization of wheat lines with preventive activity against chronic diseases. Given that cancer is the leading cause of mortality in the world and shares risk factors with obesity, type-2 diabetes, and cardiovascular disease, and given that wheat has been reported to protect against these diseases, the core collection was developed based on cancer prevalence. Methods The Germplasm Resources Information Network (GRIN database was used to identify Triticum and Aegilops species grown in regions of the world that vary in cancer prevalence based on the International Agency for Cancer Research GLOBOCAN world map of cancer statistics (2008. Cancer incidence data drove variety selection with secondary consideration of ploidy, center of origin, and climate. Results Analysis indicated that the geographic regions from which wheat is considered to have originated have a lower incidence of cancer than other geographic regions (P Conclusions A diverse core collection of wheat germplasm has been established from a range of regions worldwide. This core collection will be used to identify wheat lines with activity against chronic diseases using anticancer activity as a screening tool.

  6. Volatile Compound Profiling by HS-SPME/GC-MS-FID of a Core Olive Cultivar Collection as a Tool for Aroma Improvement of Virgin Olive Oil

    Directory of Open Access Journals (Sweden)

    Lourdes García-Vico

    2017-01-01

    Full Text Available Virgin olive oil (VOO is the only food product requiring official sensory analysis to be classified in commercial categories, in which the evaluation of the aroma plays a very important role. The selection of parents, with the aim of obtaining new cultivars with improved oil aroma, is of paramount importance in olive breeding programs. We have assessed the volatile fraction by headspace-solid-phase microextraction/gas chromatography-mass spectrometry-flame ionization detection (HS-SPME/GC-MS-FID and the deduced aroma properties of VOO from a core set of olive cultivars (Core-36 which possesses most of the genetic diversity found in the World Olive Germplasm Collection (IFAPA Alameda del Obispo located in Cordoba, Spain. The VOO volatile fractions of Core-36 cultivars display a high level of variability. It is mostly made of compounds produced from polyunsaturated fatty acids through the lipoxygenase pathway, which confirms to be a general characteristic of the olive species (Olea europaea L.. The main group of volatile compounds in the oils was six straight-chain carbon compounds derived from linolenic acid, some of them being the main contributors to the aroma of the olive oils according to their odor activity values (OAV. The high level of variability found for the volatile fraction of the oils from Core-36 and, therefore, for the aroma odor notes, suggest that this core set may be a very useful tool for the choice of optimal parents in olive breeding programs in order to raise new cultivars with improved VOO aroma.

  7. Volatile Compound Profiling by HS-SPME/GC-MS-FID of a Core Olive Cultivar Collection as a Tool for Aroma Improvement of Virgin Olive Oil.

    Science.gov (United States)

    García-Vico, Lourdes; Belaj, Angjelina; Sánchez-Ortiz, Araceli; Martínez-Rivas, José M; Pérez, Ana G; Sanz, Carlos

    2017-01-14

    Virgin olive oil (VOO) is the only food product requiring official sensory analysis to be classified in commercial categories, in which the evaluation of the aroma plays a very important role. The selection of parents, with the aim of obtaining new cultivars with improved oil aroma, is of paramount importance in olive breeding programs. We have assessed the volatile fraction by headspace-solid-phase microextraction/gas chromatography-mass spectrometry-flame ionization detection (HS-SPME/GC-MS-FID) and the deduced aroma properties of VOO from a core set of olive cultivars (Core-36) which possesses most of the genetic diversity found in the World Olive Germplasm Collection (IFAPA Alameda del Obispo) located in Cordoba, Spain. The VOO volatile fractions of Core-36 cultivars display a high level of variability. It is mostly made of compounds produced from polyunsaturated fatty acids through the lipoxygenase pathway, which confirms to be a general characteristic of the olive species (Olea europaea L.). The main group of volatile compounds in the oils was six straight-chain carbon compounds derived from linolenic acid, some of them being the main contributors to the aroma of the olive oils according to their odor activity values (OAV). The high level of variability found for the volatile fraction of the oils from Core-36 and, therefore, for the aroma odor notes, suggest that this core set may be a very useful tool for the choice of optimal parents in olive breeding programs in order to raise new cultivars with improved VOO aroma.

  8. Electromagnet Tests on Primary Control Rod Drive Mechanism of a Prototype Gen-IV SFR

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jaehan; Koo, Gyeonghoi [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The primary control system is used for power control, burn-up compensation and reactor shutdown in response to demands from the plant control or protection systems. This paper describes the lifting and holding force tests of the electromagnetic equipment of a primary control rod drive mechanism (CRDM). The supply currents above 1.5 A and 15A on coil are required for holding the CRA with a 1mm gap, and lifting the CRA with 10mm gap, respectively. The currents cover all the loads to be expected in driveline. The S10C carbon steel can be replaced with the SS410 stainless steel by increasing the supply current about 30%. The assist spring, pushing down the tension tube with a compressed force, plays an important role when the operation load is smaller than 20kgf. The spring force can cease a time delay on the free drop of the tension tube carrying a light driving mass because a residual electromagnetic force may exist for a while even though the supply power is cut off. The holding current can be reduced by closing the gap size of 1mm between inner core and armature.

  9. Core Java

    CERN Document Server

    Horstmann, Cay S

    2013-01-01

    Fully updated to reflect Java SE 7 language changes, Core Java™, Volume I—Fundamentals, Ninth Edition, is the definitive guide to the Java platform. Designed for serious programmers, this reliable, unbiased, no-nonsense tutorial illuminates key Java language and library features with thoroughly tested code examples. As in previous editions, all code is easy to understand, reflects modern best practices, and is specifically designed to help jumpstart your projects. Volume I quickly brings you up-to-speed on Java SE 7 core language enhancements, including the diamond operator, improved resource handling, and catching of multiple exceptions. All of the code examples have been updated to reflect these enhancements, and complete descriptions of new SE 7 features are integrated with insightful explanations of fundamental Java concepts.

  10. Core-shell structured α-Fe2O3@TiO2 nanocomposites with improved photocatalytic activity in the visible light region.

    Science.gov (United States)

    Xia, Yubing; Yin, Longwei

    2013-11-14

    The core-shell structured Fe2O3@TiO2 nanocomposites prepared via a heteroepitaxial growth route using the Fe2O3 spindle as a hard template display improved photocatalytic degradation activity for Rhodamine B dye under visible light irradiation. The ratio of α-Fe2O3 : TiO2 in the α-Fe2O3@TiO2 core-shell nanocomposites can be tuned by etching the α-Fe2O3 core via controlling the concentration of HCl and etching time. An appropriate concentration of the Fe2O3 core could effectively induce a transition of the optical response from the UV to the visible region and decrease the recombination rate of photogenerated electrons and the holes of the core-shell structured catalyst, greatly contributing to the enhancement of visible light response and visible light photocatalytic activity of the Fe2O3@TiO2 catalysts. It is revealed that the optical response and photocatalytic performance of the core-shell α-Fe2O3@TiO2 nanocomposites can be tuned by adjusting the molar ratio of Fe2O3 : TiO2 of the α-Fe2O3@TiO2 nanocomposites. The α-Fe2O3@TiO2 core-shell nanocomposite with an optimal molar ratio of 7% for Fe2O3 : TiO2 exhibits the best photocatalytic performance under visible light irradiation. It is shown that the Fe2O3/TiO2 heterojunction structure is responsible for the efficient visible-light photocatalytic activity. As the concentration of Fe2O3 is high, Fe(3+) ions will act as recombination centres of the photogenerated electrons and holes. The present core-shell Fe2O3@TiO2 nanoparticles displaying enhanced photodegradation activity could find potential applications as photocatalysts for the abatement of various organic pollutants.

  11. Improved hollow-core photonic crystal fiber design for delivery of nanosecond pulses in laser micromachining applications.

    Science.gov (United States)

    Shephard, Jonathan D; Couny, Francois; Russell, Phillip St J; Jones, Julian D C; Knight, Jonathan C; Hand, Duncan P

    2005-07-20

    We report the delivery of high-energy nanosecond pulses (approximately 65 ns pulse width) from a high-repetition-rate (up to 100 kHz) Q-switched Nd:YAG laser through the fundamental mode of a hollow-core photonic crystal fiber (HC-PCF) at 1064 nm. The guided mode in the HC-PCF has a low overlap with the glass, allowing delivery of pulses with energies above those attainable with other fibers. Energies greater than 0.5 mJ were delivered in a single spatial mode through the hollow-core fiber, providing the pulse energy and high beam quality required for micromachining of metals. Practical micromachining of a metal sheet by fiber delivery has been demonstrated.

  12. Study on CO{sub 2} Recovery System Design in Supercritical CO{sub 2} Cycle for SFR Application

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min Seok; Jung, Hwa-Young; Lee, Jeong Ik [KAIST, Daejeon (Korea, Republic of)

    2016-10-15

    As a part of Sodium-cooled Fast Reactor (SFR) development in Korea, the supercritical CO{sub 2} (S-CO{sub 2}) Brayton cycle is considered as an alternative power conversion system to eliminate sodium-water reaction (SWR) when the current conventional steam Rankine cycle is utilized with SFR. The parasitic loss caused by the leakage flow should be minimized since this greatly influences the cycle efficiency. Thus, a simple model for estimating the critical flow in a turbo-machinery seal was developed to predict the leakage flow rate and calculate the required total mass of working fluid in a S-CO{sub 2} power system to minimize the parasitic loss. In this work, study on CO{sub 2} recovery system design was conducted by finding the suitable recovery point with the developed simple CO{sub 2} critical flow model and sensitivity analysis was performed on the power system performance with respect to multiple CO{sub 2} recovery process options. The study of a CO{sub 2} recovery system design was conducted to minimize the thermal efficiency losses caused by CO{sub 2} inventory recovery system. For the first step, the configuration of a seal was selected. A labyrinth seal has suitable features for the S-CO{sub 2} power cycle application. Then, thermal efficiency losses with different CO{sub 2} leak rate and recovery point were evaluated. To calculate the leak rate in turbo-machinery by using the developed CO{sub 2} critical flow model, the conditions of storage tank is set to be closer to the recovery point. After modifying the critical flow model appropriately, total mass flow rate of leakage flow was calculated. Finally, the CO{sub 2} recovery system design work was performed to minimize the loss of thermal efficiency. The suggested system is not only simple and intuitive but also has relatively very low additional work loss from the compressor than other considered systems. When each leak rate is set to the conventional leakage rate of 1 kg/s per seal, the minimum and

  13. Polydopamine-coated, nitrogen-doped, hollow carbon-sulfur double-layered core-shell structure for improving lithium-sulfur batteries.

    Science.gov (United States)

    Zhou, Weidong; Xiao, Xingcheng; Cai, Mei; Yang, Li

    2014-09-10

    To better confine the sulfur/polysulfides in the electrode of lithium-sulfur (Li/S) batteries and improve the cycling stability, we developed a double-layered core-shell structure of polymer-coated carbon-sulfur. Carbon-sulfur was first prepared through the impregnation of sulfur into hollow carbon spheres under heat treatment, followed by a coating polymerization to give a double-layered core-shell structure. From the study of scanning transmission electron microscopy (STEM) images, we demonstrated that the sulfur not only successfully penetrated through the porous carbon shell but also aggregated along the inner wall of the carbon shell, which, for the first time, provided visible and convincing evidence that sulfur preferred diffusing into the hollow carbon rather than aggregating in/on the porous wall of the carbon. Taking advantage of this structure, a stable capacity of 900 mA h g(-1) at 0.2 C after 150 cycles and 630 mA h g(-1) at 0.6 C after 600 cycles could be obtained in Li/S batteries. We also demonstrated the feasibility of full cells using the sulfur electrodes to couple with the silicon film electrodes, which exhibited significantly improved cycling stability and efficiency. The remarkable electrochemical performance could be attributed to the desirable confinement of sulfur through the unique double-layered core-shell architectures.

  14. Improved L-C resonant decay technique for Q measurement of quasilinear power inductors: New results for MPP and ferrite powdered cores

    Science.gov (United States)

    Niedra, Janis M.; Gerber, Scott S.

    1995-01-01

    The L-C resonant decay technique for measuring circuit Q or losses is improved by eliminating the switch from the inductor-capacitor loop. A MOSFET switch is used instead to momentarily connect the resonant circuit to an existing voltage source, which itself is gated off during the decay transient. Very reproducible, low duty cycle data could be taken this way over a dynamic voltage range of at least 10:1. Circuit Q is computed from a polynomial fit to the sequence of the decaying voltage maxima. This method was applied to measure the losses at 60 kHz in inductors having loose powder cores of moly permalloy and an Mn-Zn power ferrite. After the copper and capacitor losses are separated out, the resulting specific core loss is shown to be roughly as expected for the MPP powder, but anomalously high for the ferrite powder. Possible causes are mentioned.

  15. Dust temperature and CO-to-H2 conversion factor variations in the SFR-M* plane

    CERN Document Server

    Magnelli, B; Lutz, D; Tacconi, L J; Berta, S; Bournaud, F; Charmandaris, V; Dannerbauer, H; Elbaz, D; Förster-Schreiber, N M; Graciá-Carpio, J; Ivison, R; Maiolino, R; Nordon, R; Popesso, P; Rodighiero, G; Santini, P; Wuyts, S

    2012-01-01

    Deep Herschel imaging and 12CO(2-1) line luminosities from the IRAM PdBI are combined for a sample of 17 galaxies at z>1 from the GOODS-N field. The sample includes galaxies both on and above the main sequence (MS) traced by star-forming galaxies in the SFR-M* plane. The far-infrared data are used to derive dust masses, Mdust. Combined with an empirical prescription for the dependence of the gas-to-dust ratio on metallicity (GDR), the CO luminosities and Mdust values are used to derive for each galaxy the CO-to-H2 conversion factor, alpha_co. Like in the local Universe, the value of alpha_co is a factor of ~5 smaller in starbursts compared to normal star-forming galaxies (SFGs). We also uncover a relation between alpha_co and dust temperature (Tdust; alpha_co decreasing with increasing Tdust) as obtained from modified blackbody fits to the far-infrared data. While the absolute normalization of the alpha_co(Tdust) relation is uncertain, the global trend is robust against possible systematic biases in the deter...

  16. Using Water Vapor Isotope Observations from above the Greenland Ice Sheet to improve the Interpretation of Ice Core Water Stable Isotope Records

    Science.gov (United States)

    Steen-Larsen, H. C.; Masson-Delmotte, V.; Risi, C. M.; Yoshimura, K.; Werner, M.; Butzin, M.; Brun, E.; Landais, A.; Bonne, J. L.; Dahl-Jensen, D.

    2014-12-01

    Water stable isotope data from Greenland ice cores provide key paleoclimatic information. For the purpose of improving the climatic interpretation from ice core records, a monitoring of the isotopic composition δ18O and δD at several height levels (up to 13 meter) of near-surface water vapor, precipitation and snow in the first 0.5 cm surface layer has been conducted during three summers (2010-2012) at NEEM, NW Greenland. We compare the observed water vapor isotopic composition with model outputs from three isotope-enabled general circulation models: LMDZiso, isoGSM, ECHAM-wiso. This allows us to benchmark the models and address effect of model resolution, effect of transport, effect of isotope parameterization, and representation of significant source region contributions. We find for all models that the simulated isotopic value δD are significantly biased towards too enriched values. A bias, which is only partly explained by the air temperature. The simulated amplitude in d-excess variations is ~50% smaller than observed and the simulated average summer level is ~10‰ lower than in observations. Using back trajectories we observe water vapor of Arctic origin to have a high d-excess fingerprint. This fingerprint is not observed in the GCMiso simulations indicating a problem of simulating accurately the Arctic hydrological cycle. The bias in the simulated δD and d-excess water vapor is similar to the already-documented bias in the simulated δD and d-excess of Greenland ice core records. This suggests that if we improve the simulation of the water vapor isotopic composition we might also improve the simulation of the ice core isotope record. During periods between precipitation events, our data demonstrate parallel changes of δ18O and d-excess in surface snow and near-surface vapor. The changes in δ18O of the vapor are similar or larger than those of the snow δ18O. It is estimated using the CROCUS snow model that 6 to 20% of the surface snow mass is

  17. Proteomics Core

    Data.gov (United States)

    Federal Laboratory Consortium — Proteomics Core is the central resource for mass spectrometry based proteomics within the NHLBI. The Core staff help collaborators design proteomics experiments in a...

  18. Proteomics Core

    Data.gov (United States)

    Federal Laboratory Consortium — Proteomics Core is the central resource for mass spectrometry based proteomics within the NHLBI. The Core staff help collaborators design proteomics experiments in...

  19. Assessment of SFR fuel pin performance codes under advanced fuel for minor actinide transmutation

    Energy Technology Data Exchange (ETDEWEB)

    Bouineau, V.; Lainet, M.; Chauvin, N.; Pelletier, M. [French Alternative Energies and Atomic Energy Commission - CEA, CEA Cadarache, DEN/DEC/SESC, 13108 Saint Paul lez Durance (France); Di Marcello, V.; Van Uffelen, P.; Walker, C. [European Commission, Joint Research Centre, Institute for Transuranium Elements, Hermann-von-Helmholtz-Platz 1, D- 76344 Eggenstein-Leopoldshafen (Germany)

    2013-07-01

    Americium is a strong contributor to the long term radiotoxicity of high activity nuclear waste. Transmutation by irradiation in nuclear reactors of long-lived nuclides like {sup 241}Am is, therefore, an option for the reduction of radiotoxicity and residual power packages as well as the repository area. In the SUPERFACT Experiment four different oxide fuels containing high and low concentrations of {sup 237}Np and {sup 241}Am, representing the homogeneous and heterogeneous in-pile recycling concepts, were irradiated in the PHENIX reactor. The behavior of advanced fuel materials with minor actinide needs to be fully characterized, understood and modeled in order to optimize the design of this kind of fuel elements and to evaluate its performances. This paper assesses the current predictability of fuel performance codes TRANSURANUS and GERMINAL V2 on the basis of post irradiation examinations of the SUPERFACT experiment for pins with low minor actinide content. Their predictions have been compared to measured data in terms of geometrical changes of fuel and cladding, fission gases behavior and actinide and fission product distributions. The results are in good agreement with the experimental results, although improvements are also pointed out for further studies, especially if larger content of minor actinide will be taken into account in the codes. (authors)

  20. Application of core-shell-structured CdTe-SiO{sub 2} quantum dots synthesized via a facile solution method for improving latent fingerprint detection

    Energy Technology Data Exchange (ETDEWEB)

    Gao Feng; Han Jiaxing; Lv Caifeng; Wang Qin; Zhang Jun, E-mail: cejzhang@imu.edu.cn [Inner Mongolia University, College of Chemistry and Chemical Engineering (China); Li Qun; Bao Liru; Li Xin [Division of Science and Technology, Public Security Department of Inner Mongolia (China)

    2012-10-15

    Fingerprint detection is important in criminal investigation. This paper reports a facile powder brushing technique for improving latent fingerprint detection using core-shell-structured CdTe-SiO{sub 2} quantum dots (QDs) as fluorescent labeling marks. Core-shell-structured CdTe-SiO{sub 2} QDs are prepared via a simple solution-based approach using NH{sub 2}NH{sub 2}{center_dot}H{sub 2}O as pH adjustor and stabilizer, and their application for improving latent fingerprint detection is explored. The obtained CdTe-SiO{sub 2} QDs show spherical shapes with well-defined core-shell structures encapsulating different amounts of QDs depending on the type of the pH adjustor and stabilizer. Moreover, the fluorescence of CdTe-SiO{sub 2} QDs is largely enhanced by surface modification of the SiO{sub 2} shell. The CdTe-SiO{sub 2} QDs overcome the oxidation problem of pure CdTe QDs in air, thus affording better variability with strong adhesive ability, better resolution, and bright emission colors for practical application in latent fingerprint detection. In comparison with the conventional fluorescence powders, silver powders, and others, the effectiveness of CdTe-SiO{sub 2} QD powders for detection of latent fingerprints present on a large variety of object surfaces is greatly improved. The synthesis method for CdTe-SiO{sub 2} QDs is simple, cheap, and easy for large-scale production, and thus offers many advantages in the practical application of fingerprint detection.

  1. The role of galaxy interaction in the SFR-M {sub *} relation: characterizing morphological properties of Herschel-selected galaxies at 0.2 < z < 1.5

    Energy Technology Data Exchange (ETDEWEB)

    Hung, Chao-Ling; Sanders, D. B.; Casey, C. M.; Lee, N.; Barnes, J. E.; Koss, M.; Larson, K. L.; Lockhart, K.; Man, A. W. S.; Mann, A. W. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Capak, P. [Spitzer Science Center, MS 314-6, California Institute of Technology, Pasadena, CA 91125 (United States); Kartaltepe, J. S. [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Le Floc' h, E. [UMR AIM (CEA-UP7-CNRS), CEA-Saclay, Orme des Merisiers, bât. 709, F-91191 Gif-sur-Yvette Cedex (France); Riguccini, L. [NASA Ames Research Center, Moffett Field, CA (United States); Scoville, N. [California Institute of Technology, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Symeonidis, M., E-mail: clhung@ifa.hawaii.edu [University of Sussex, Department of Physics and Astronomy, Pevensey 2 Building, Falmer, Brighton BN1 9QH, Sussex (United Kingdom)

    2013-12-01

    Galaxy interactions/mergers have been shown to dominate the population of IR-luminous galaxies (L {sub IR} ≳ 10{sup 11.6} L {sub ☉}) in the local universe (z ≲ 0.25). Recent studies based on the relation between galaxies' star formation rates and stellar mass (the SFR-M {sub *} relation or the {sup g}alaxy main sequence{sup )} have suggested that galaxy interaction/mergers may only become significant when galaxies fall well above the galaxy main sequence. Since the typical SFR at a given M {sub *} increases with redshift, the existence of the galaxy main sequence implies that massive, IR-luminous galaxies at high z may not necessarily be driven by galaxy interactions. We examine the role of galaxy interactions in the SFR-M {sub *} relation by carrying out a morphological analysis of 2084 Herschel-selected galaxies at 0.2 < z < 1.5 in the COSMOS field. Using a detailed visual classification scheme, we show that the fraction of 'disk galaxies' decreases and the fraction of 'irregular' galaxies increases systematically with increasing L {sub IR} out to z ≲ 1.5 and z ≲ 1.0, respectively. At L {sub IR} >10{sup 11.5} L {sub ☉}, ≳ 50% of the objects show evident features of strongly interacting/merger systems, where this percentage is similar to the studies of local IR-luminous galaxies. The fraction of interacting/merger systems also systematically increases with the deviation from the SFR-M {sub *} relation, supporting the view that galaxies falling above the main sequence are more dominated by mergers than the main-sequence galaxies. Meanwhile, we find that ≳ 18% of massive IR-luminous 'main-sequence galaxies' are classified as interacting systems, where this population may not evolve through the evolutionary track predicted by a simple gas exhaustion model.

  2. The contribution of adenines in the catalytic core of 10-23 DNAzyme improved by the 6-amino group modifications.

    Science.gov (United States)

    Zhu, Junfei; Li, Zhiwen; Wang, Qi; Liu, Yang; He, Junlin

    2016-09-15

    In the catalytic core of 10-23 DNAzyme, its five adenine residues are moderate conservative, but with highly conserved functional groups like 6-amino group and 7-nitrogen atom. It is this critical conservation that these two groups could be modified for better contribution. With 2'-deoxyadenosine analogues, several functional groups were introduced at the 6-amino group of the five adenine residues. 3-Aminopropyl substituent at 6-amino group of A15 resulted in a five-fold increase of kobs. More efficient DNAzymes are expected by delicate design of the linkage and the external functional groups for this 6-amino group of A15. With this modification approach, other functional groups or residues could be optimized for 10-23 DNAzyme.

  3. An improved method for quantitatively measuring the sequences of total organic carbon and black carbon in marine sediment cores

    Science.gov (United States)

    Xu, Xiaoming; Zhu, Qing; Zhou, Qianzhi; Liu, Jinzhong; Yuan, Jianping; Wang, Jianghai

    2017-04-01

    Understanding global carbon cycle is critical to uncover the mechanisms of global warming and remediate its adverse effects on human activities. Organic carbon in marine sediments is an indispensable part of the global carbon reservoir in global carbon cycling. Evaluating such a reservoir calls for quantitative studies of marine carbon burial, which closely depend on quantifying total organic carbon and black carbon in marine sediment cores and subsequently on obtaining their high-resolution temporal sequences. However, the conventional methods for detecting the contents of total organic carbon or black carbon cannot resolve the following specific difficulties, i.e., (1) a very limited amount of each subsample versus the diverse analytical items, (2) a low and fluctuating recovery rate of total organic carbon or black carbon versus the reproducibility of carbon data, and (3) a large number of subsamples versus the rapid batch measurements. In this work, (i) adopting the customized disposable ceramic crucibles with the micropore-controlled ability, (ii) developing self-made or customized facilities for the procedures of acidification and chemothermal oxidization, and (iii) optimizing procedures and carbon-sulfur analyzer, we have built a novel Wang-Xu-Yuan method (the WXY method) for measuring the contents of total organic carbon or black carbon in marine sediment cores, which includes the procedures of pretreatment, weighing, acidification, chemothermal oxidation and quantification; and can fully meet the requirements of establishing their highresolution temporal sequences, whatever in the recovery, experimental efficiency, accuracy and reliability of the measurements, and homogeneity of samples. In particular, the usage of disposable ceramic crucibles leads to evidently simplify the experimental scenario, which further results in the very high recovery rates for total organic carbon and black carbon. This new technique may provide a significant support for

  4. Long-term follow-up of a randomized controlled trial on additional core stability exercises training for improving dynamic sitting balance and trunk control in stroke patients.

    Science.gov (United States)

    Cabanas-Valdés, Rosa; Bagur-Calafat, Caritat; Girabent-Farrés, Montserrat; Caballero-Gómez, Fernanda Mª; du Port de Pontcharra-Serra, Helena; German-Romero, Ana; Urrútia, Gerard

    2017-03-01

    Analyse the effect of core stability exercises in addition to conventional physiotherapy training three months after the intervention ended. A randomized controlled trial. Outpatient services. Seventy-nine stroke survivors. In the intervention period, both groups underwent conventional physiotherapy performed five days/week for five weeks, and in addition the experimental group performed core stability exercises for 15 minutes/day. Afterwards, during a three-month follow-up period, both groups underwent usual care that could eventually include conventional physiotherapy or physical exercise but not in a controlled condition. Primary outcome was trunk control and dynamic sitting balance assessed by the Spanish-Version of Trunk Impairment Scale 2.0 and Function in Sitting Test. Secondary outcomes were standing balance and gait evaluated by the Berg Balance Scale, Tinetti Test, Brunel Balance Assessment, Spanish-Version of Postural Assessment Scale for Stroke and activities of daily living using the Barthel Index. A total of 68 subjects out of 79 completed the three-month follow-up period. The mean difference (SD) between groups was 0.78 (1.51) points ( p = 0.003) for total score on the Spanish-Version of Trunk Impairment Scale 2.0, 2.52 (6.46) points ( p = 0.009) for Function in Sitting Test, dynamic standing balance was 3.30 (9.21) points ( p= 0.009) on the Berg Balance Scale, gait was 0.82 (1.88) points ( p = 0.002) by Brunel Balance Assessment (stepping), and 1.11 (2.94) points ( p = 0.044) by Tinetti Test (gait), all in favour of core stability exercises. Core stability exercises plus conventional physiotherapy have a positive long-term effect on improving dynamic sitting and standing balance and gait in post-stroke patients.

  5. Two Dimensional Near-field Calculations of Radionuclide Releases from the Vaults of the SFR 1 Repository

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Antonio [AlbaNova University Center, Stockholm Center of Physics, Astronomy and Biotechnology (Sweden). Dept. of Physics; Sundstroem, Benny [Swedish Nuclear Power Inspectorate, Stockholm (Sweden)

    2003-12-01

    Radionuclide releases from the near-field for the vaults of the SFR 1 repository are examined in this report. To model those releases we have developed four models, one for each of the vaults; 2BTF, 1BTF, BMA and BLA. The respective codes are based on the finite element method and are called FEMBTF2, FEMBTF1, FEMBMA and FEMBLA, respectively. These codes are two-dimensional representations of the cross sections of the vaults. The different barriers of the vaults have been modelled individually using the physical dimensions of the cross sections. The same conceptual model has been used to estimate the releases from the near-field. This conceptual model is implemented by four different FEM codes that solve the two-dimensional transport equation, e.g. the advective-diffusive-reactive equation that also includes radioactive decay. An interesting property of the codes is that they allow the use of time-dependent properties to represent for instance the evolution of water flow, porosities, distribution coefficients etc. This capability of the code has been used only in some cases because the FEM codes put heavy requirements on the computer's CPU. The nuclides studied here were chosen from a set representing the highest release rates from the near-field obtained by SKB during their project SAFE. Some of the results reported here are somewhat lower than SKBs, other higher. Uncertainties in the conceptual models and differences in the input data are the reasons for the numerical differences. For most cases, the differences between our results and those of SKB should be considered relatively small within present context of near-field calculations.

  6. Proliferation Resistance and Safeguardability Assessment of a SFR Metal Fuel Manufacturing Facility (SFMF) using the INPRO Methodology

    Energy Technology Data Exchange (ETDEWEB)

    Chang, H. L.; Ko, W. I.; Park, S. H.; Kim, H. D.; Park, G. I. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    To illustrate the proposed Prosta process, to demonstrate its usefulness, and to provide input to a revision of the INPRO manual in the area of proliferation resistance, a case study has been carried out with a conceptually designed sodium cooled fast reactor (SFR) metal fuel manufacturing facility (SFMF), representing novel technology still in the conceptual design phase. A coarse acquisition path analysis has been carried out of the SFMF to demonstrate the assessment process with identified different target materials. The case study demonstrates the usefulness of the proposed PROSA PR assessment process and the interrelationship of the PR assessment with the safeguards-by-design process, identifying potential R and D needs. The PROSA process has been applied to a conceptually designed SFMF, representing novel technology that is still in the conceptual design phase at KAERI. The case study demonstrated that the proposed PROSA process is simpler and easier to perform than the original INPRO methodology and can be applied from the early stage of design showing the relationship of PR assessment to the safeguard-by-design process. New evaluation questionnaire for UR1 is more logical and comprehensive, and provides the legal basis enabling the IAEA to achieve its safeguards objectives including the detection of undeclared nuclear materials and activities. NES information catalogue replacing UR2 was a useful modification and supports safeguardability assessment at the NES and facility level. The proposed PROSA process is also capable to identify strengths and weaknesses of a system in the area of proliferation resistance in a generally understandable form, including R and D gaps that need to be filled in order to meet the criteria for proliferation resistance of a nuclear energy system.

  7. Improvement of the physical properties of ZnO/CdTe core-shell nanowire arrays by CdCl2 heat treatment for solar cells.

    Science.gov (United States)

    Consonni, Vincent; Renet, Sébastien; Garnier, Jérôme; Gergaud, Patrice; Artús, Lluis; Michallon, Jérôme; Rapenne, Laetitia; Appert, Estelle; Kaminski-Cachopo, Anne

    2014-01-01

    CdTe is an important compound semiconductor for solar cells, and its use in nanowire-based heterostructures may become a critical requirement, owing to the potential scarcity of tellurium. The effects of the CdCl2 heat treatment are investigated on the physical properties of vertically aligned ZnO/CdTe core-shell nanowire arrays grown by combining chemical bath deposition with close space sublimation. It is found that recrystallization phenomena are induced by the CdCl2 heat treatment in the CdTe shell composed of nanograins: its crystallinity is improved while grain growth and texture randomization occur. The presence of a tellurium crystalline phase that may decorate grain boundaries is also revealed. The CdCl2 heat treatment further favors the chlorine doping of the CdTe shell with the formation of chlorine A-centers and can result in the passivation of grain boundaries. The absorption properties of ZnO/CdTe core-shell nanowire arrays are highly efficient, and more than 80% of the incident light can be absorbed in the spectral range of the solar irradiance. The resulting photovoltaic properties of solar cells made from ZnO/CdTe core-shell nanowire arrays covered with CuSCN/Au back-side contact are also improved after the CdCl2 heat treatment. However, recombination and trap phenomena are expected to operate, and the collection of the holes that are mainly photo-generated in the CdTe shell from the CuSCN/Au back-side contact is presumably identified as the main critical point in these solar cells.

  8. Dual-shell hollow polyaniline/sulfur-core/polyaniline composites improving the capacity and cycle performance of lithium–sulfur batteries

    Energy Technology Data Exchange (ETDEWEB)

    An, Yanling; Wei, Pan; Fan, Meiqiang, E-mail: fanmeiqiang@126.com; Chen, Da; Chen, Haichao; Ju, QiangJian; Tian, Guanglei; Shu, Kangying

    2016-07-01

    Highlights: • A dual core-shell hPANI/S/PANI composite was prepared in situ synthesis. • Cycle performance of the hPANI/S/PANI composite was enhanced. • The improvement was due to fine sulfur particles wrapped by two PANI films. • Some positive effects were elaborated. - Abstract: In this study, a dual-shell hollow polyaniline/sulfur-core/polyaniline (hPANI/S/PANI) composite was prepared by successively depositing PANI, S, and PANI on the surface of a template silicon sphere. The electrochemical properties of this composite were evaluated using a lithium plate as an anode in lithium/sulfur cells. The hPANI/S/PANI composite showed a discharge capacity of 572.2 mAh g{sup −1} after 214 cycles at 0.1 C, and the Coulombic efficiency was above 87% in the whole charge/discharge cycle. The improved cycle property of the hPANI/S/PANI composite can be ascribed to the fine sulfur particles homogeneously deposited on the PANI surface and sprawled inside the two PANI layers during the charge/discharge cycle. This behavior stabilized the nanostructure of sulfur and enhanced its conductivity.

  9. Next generation self-shielded flux cored electrode with improved toughness for off shore oil well platform structures

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Daya; Soltis, Patrick; Narayanan, Badri; Quintana, Marie; Fox, Jeff [The Lincoln Electric Company (United States)

    2005-07-01

    Self-shielded flux cored arc welding electrodes (FCAW-S) are ideal for outdoor applications, particularly open fabrication yards where high winds are a possibility. Development work was carried out on a FCAW-S electrode for welding 70 and 80 ksi yield strength base materials with a required minimum average Charpy V-Notch (CVN) absorbed energy value of 35 ft-lb at -40 deg F in the weld metal. The effect of Al, Mg, Ti, and Zr on CVN toughness was evaluated by running a Design of Experiments approach to systematically vary the levels of these components in the electrode fill and, in turn, the weld metal. These electrodes were used to weld simulated pipe joints. Over the range of compositions tested, 0.05% Ti in the weld metal was found to be optimum for CVN toughness. Ti also had a beneficial effect on the usable voltage range. Simulated offshore joints were welded to evaluate the effect of base metal dilution, heat input, and welding procedure on the toughness of weld metal. CVN toughness was again measured at -40 deg F on samples taken from the root and the cap pass regions. The root pass impact toughness showed strong dependence on the base metal dilution and the heat input used to weld the root and fill passes. (author)

  10. New Hybrid Multiple Attribute Decision-Making Model for Improving Competence Sets: Enhancing a Company’s Core Competitiveness

    Directory of Open Access Journals (Sweden)

    Kuan-Wei Huang

    2016-02-01

    Full Text Available A company’s core competitiveness depends on the strategic allocation of its human resources in alignment with employee capabilities. Competency models can identify the range of capabilities at a company’s disposal, and this information can be used to develop internal or external education training policies for sustainable development. Such models can ensure the importation of a strategic orientation reflecting the growth of its employee competence set and enhancing human resource sustainably. This approach ensures that the most appropriate people are assigned to the most appropriate positions. In this study, we proposed a new hybrid multiple attributed decision-making model by using the Decision-making trial and Evaluation Laboratory Technique (DEMATEL to construct an influential network relation map (INRM and determined the influential weights by using the basic concept of the analytic network process (called DEMATEL-based ANP, DANP; the influential weights were then adopted with a modified Vise Kriterijumska Optimizacija I Kompromisno Resenje (VIKOR method. A simple forecasting technique as an iteration function was also proposed. The proposed model was effective. We expect that the proposed model can facilitate making timely revisions, reflecting the growth of employee competence sets, reducing the performance gap toward the aspiration level, and ensuring the sustainability of a company.

  11. An Improved Multipole Approximation for Self-Gravity and Its Importance for Core-Collapse Supernova Simulations

    CERN Document Server

    Couch, Sean M; Flocke, Norbert

    2013-01-01

    Self-gravity computation by multipole expansion is a common approach in problems such as core-collapse and Type Ia supernovae, where single large condensations of mass must be treated. The standard formulation of multipole self-gravity suffers from two significant sources of error, which we correct in the formulation presented in this article. The first source of error is due to the numerical approximation that effectively places grid cell mass at the central point of the cell, then computes the gravitational potential at that point, resulting in a convergence failure of the multipole expansion. We describe a new scheme that avoids this problem by computing gravitational potential at cell faces. The second source of error is due to sub-optimal choice of location for the expansion center, which results in angular power at high multipole $l$ values in the gravitational field, requiring a high --- and expensive --- value of multipole cutoff \\lmax. By introducing a global measure of angular power in the gravitati...

  12. Development of an improved wearable device for core body temperature monitoring based on the dual heat flux principle.

    Science.gov (United States)

    Feng, Jingjie; Zhou, Congcong; He, Cheng; Li, Yuan; Ye, Xuesong

    2017-04-01

    In this paper, a miniaturized wearable core body temperature (CBT) monitoring system based on the dual heat flux (DHF) principle was developed. By interspersing calcium carbonate powder in PolyDimethylsiloxane (PDMS), a reformative heat transfer medium was produced to reduce the thermal equilibrium time. Besides, a least mean square (LMS) algorithm based active noise cancellation (ANC) method was adopted to diminish the impact of ambient temperature fluctuations. Theoretical analyses, finite element simulation, experiments on a hot plate and human volunteers were performed. The results showed that the proposed system had the advantages of small size, reduced initial time (~23.5 min), and good immunity to fluctuations of the air temperature. For the range of 37-41 °C on the hot plate, the error compared with a Fluke high accuracy thermometer was 0.08  ±  0.20 °C. In the human experiments, the measured temperature in the rest trial (34 subjects) had a difference of 0.13  ±  0.22 °C compared with sublingual temperature, while a significant increase of 1.36  ±  0.44 °C from rest to jogging was found in the exercise trial (30 subjects). This system has the potential for reliable continuous CBT measurement in rest and can reflect CBT variations during exercise.

  13. Improving communication skill training in patient centered medical practice for enhancing rational use of laboratory tests: The core of bioinformation for leveraging stakeholder engagement in regulatory science.

    Science.gov (United States)

    Moura, Josemar de Almeida; Costa, Bruna Carvalho; de Faria, Rosa Malena Delbone; Soares, Taciana Figueiredo; Moura, Eliane Perlatto; Chiappelli, Francesco

    2013-01-01

    Requests for laboratory tests are among the most relevant additional tools used by physicians as part of patient's health problemsolving. However, the overestimation of complementary investigation may be linked to less reflective medical practice as a consequence of a poor physician-patient communication, and may impair patient-centered care. This scenario is likely to result from reduced consultation time, and a clinical model focused on the disease. We propose a new medical intervention program that specifically targets improving the patient-centered communication of laboratory tests results, the core of bioinformation in health care. Expectations are that medical students training in communication skills significantly improve physicians-patient relationship, reduce inappropriate use of laboratorial tests, and raise stakeholder engagement.

  14. Summary of Structural Concept Development and High Temperature Structural Integrity Evaluation Technology for a Gen-IV SFR

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Han; Joo, Young Sang; Lee, Hyeong Yeon (and others)

    2008-04-15

    The economic improvement is a hot issue as one of Gen IV nuclear plant goals. It requires many researches and development works to meet the goal by securing the same level of plant safety. One of the key research items is the increase of the plant capacity with the minimum number of components and loops. Through the successful conceptual design experience for the KALIMER-600, the structural design study for a 1200MWe large capacity of sodium-cooled fast reactor has been performed to achieve the above plant size effects. The component number and reactor structural sizing were determined based on the core and fluid system design information. Several researches were performed to reduce the construction cost of NSSS in structural point of view, for example, a simplified component arrangement, concept proposals of integrated components, a high temperature LBB application technology, and an innovative in-service inspection (ISI) tool, and a computer program development of the ASME-NH design procedure of the class 1 structure and component under high temperature over 500 .deg. C. The IHTS piping arrangement was also proposed to minimize the length through the properly locating the SG and pump by 126m. Further studies of these concepts are required to confirm on the fabricability and the structural integrity for the operating and design loads. The proposed concepts will be optimized to a unified conceptual design through several trade-off studies.

  15. Using Classroom Assessment to Improve Student Learning: Math Problems Aligned with NCTM and Common Core State Standards

    Science.gov (United States)

    Collins, Anne

    2011-01-01

    Linking assessment to everyday classroom instruction requires a shift in both thinking and practice. For many, the term "assessment" simply means "grade". "Using Classroom Assessment to Improve Student Learning" shows how teachers can move away from using tests, letter or numerical grades, or passing or failing as evidence of student learning to…

  16. Trust in Schools: A Core Resource for Improvement. A Volume in the American Sociological Association's Rose Series in Sociology.

    Science.gov (United States)

    Bryk, Anthony S.; Schneider, Barbara

    This book uses case studies of 12 Chicago elementary schools undergoing reform (in response to the Chicago School Reform Act of 1988) to examine how effective social relationships can serve as a prime resource for school improvement. It discusses how the myriad social exchanges that make up daily life in a school community generate, or fail to…

  17. Rational Improvement of Molar Absorptivity Guided by Oscillator Strength: A Case Study with Furoindolizine-Based Core Skeleton.

    Science.gov (United States)

    Lee, Youngjun; Jo, Ala; Park, Seung Bum

    2015-12-21

    The rational improvement of photophysical properties can be highly valuable for the discovery of novel organic fluorophores. Using our new design strategy guided by the oscillator strength, we developed a series of full-color-tunable furoindolizine analogs with improved molar absorptivity through the fusion of a furan ring into the indolizine-based Seoul fluorophore. The excellent correlation between the computable values (oscillator strength and theoretical S0 -S1 energy gap) and photophysical properties (molar absorptivity and emission wavelength) confirmed the effectualness of our design strategy. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution Non-Commercial NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

  18. Comparative study of the relationships between CO isotopic luminosities and infrared luminosity for the Galactic dense cores

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Combining the 12CO(1-0),13CO(1-0),and C18O(1-0) data with IRAS four band data,we here estimate the physical parameters such as size,viral mass,and CO J=1-0 isotopic and infrared luminosities for 29 dense molecular clouds from two published CO samples. We further analyze the various correlations between CO J=1-0 isotopic luminosities and infrared luminosity(star formation rate,SFR) and discuss the relationships between the molecular gas tracers and SFR. The results show that 12CO(1-0),13CO(1-0) and C18O(1-0) luminosities have tight correlations with each other. CO J=1-0 isotopic luminosities and SFR show weak correlations with larger scatter than the HCN-IR correlations of 47 dense cores in the Galaxy and 65 external star-forming galaxies. This might be interpreted as that both the SFR and star formation efficiency are mainly determined by the molecular gas at high volume density rather than high column density.

  19. Advanced Burner Reactor with Breed-and-Burn Thorium Blankets for Improved Economics and Resource Utilization

    Energy Technology Data Exchange (ETDEWEB)

    Greenspan, Ehud [Univ. of California, Berkeley, CA (United States)

    2015-11-04

    This study assesses the feasibility of designing Seed and Blanket (S&B) Sodium-cooled Fast Reactor (SFR) to generate a significant fraction of the core power from radial thorium fueled blankets that operate on the Breed-and-Burn (B&B) mode without exceeding the radiation damage constraint of presently verified cladding materials. The S&B core is designed to maximize the fraction of neutrons that radially leak from the seed (or “driver”) into the subcritical blanket and reduce neutron loss via axial leakage. The blanket in the S&B core makes beneficial use of the leaking neutrons for improved economics and resource utilization. A specific objective of this study is to maximize the fraction of core power that can be generated by the blanket without violating the thermal hydraulic and material constraints. Since the blanket fuel requires no reprocessing along with remote fuel fabrication, a larger fraction of power from the blanket will result in a smaller fuel recycling capacity and lower fuel cycle cost per unit of electricity generated. A unique synergism is found between a low conversion ratio (CR) seed and a B&B blanket fueled by thorium. Among several benefits, this synergism enables the very low leakage S&B cores to have small positive coolant voiding reactivity coefficient and large enough negative Doppler coefficient even when using inert matrix fuel for the seed. The benefits of this synergism are maximized when using an annular seed surrounded by an inner and outer thorium blankets. Among the high-performance S&B cores designed to benefit from this unique synergism are: (1) the ultra-long cycle core that features a cycle length of ~7 years; (2) the high-transmutation rate core where the seed fuel features a TRU CR of 0.0. Its TRU transmutation rate is comparable to that of the reference Advanced Burner Reactor (ABR) with CR of 0.5 and the thorium blanket can generate close to 60% of the core power; but requires only one sixth of the reprocessing and

  20. Surgery and Medicine Residents' Perspectives of Morbidity and Mortality Conference: An Interdisciplinary Approach to Improve ACGME Core Competency Compliance.

    Science.gov (United States)

    Flynn-O'Brien, Katherine T; Mandell, Samuel P; Eaton, Erik Van; Schleyer, Anneliese M; McIntyre, Lisa K

    2015-01-01

    Morbidity and mortality conferences (MMCs) are often used to fulfill the Accreditation Council for Graduate Medical Education practice-based learning and improvement (PBLI) competency, but there is variation among institutions and disciplines in their approach to MMCs. The objective of this study is to examine the trainees' perspective and experience with MMCs and adverse patient event (APE) reporting across disciplines to help guide the future implementation of an institution-wide, workflow-embedded, quality improvement (QI) program for PBLI. Between April 1, 2013, and May 8, 2013, surgical and medical residents were given a confidential survey about APE reporting practices and experience with and attitudes toward MMCs and other QI/patient safety initiatives. Descriptive statistics and univariate analyses using the chi-square test for independence were calculated for all variables. Logistic regression and ordered logistic regression were used for nominal and ordinal categorical dependent variables, respectively, to calculate odds of reporting APEs. Qualitative content analysis was used to code free-text responses. A large, multihospital, tertiary academic training program in the Pacific Northwest. Residents in all years of training from the Accreditation Council for Graduate Medical Education-accredited programs in surgery and internal medicine. Survey response rate was 46.2% (126/273). Although most respondents agreed or strongly agreed that knowledge of and involvement in QI/patient safety activities was important to their training (88.1%) and future career (91.3%), only 10.3% regularly or frequently reported APEs to the institution's established electronic incident reporting system. Senior-level residents in both surgery and medicine were more likely to report APEs than more junior-level residents were (odds ratio = 4.8, 95% CI: 3.1-7.5). Surgery residents had a 4.9 (95% CI: 2.3-10.5) times higher odds than medicine residents had to have reported an APE to

  1. Ice cores

    DEFF Research Database (Denmark)

    Svensson, Anders

    2014-01-01

    Ice cores from Antarctica, from Greenland, and from a number of smaller glaciers around the world yield a wealth of information on past climates and environments. Ice cores offer unique records on past temperatures, atmospheric composition (including greenhouse gases), volcanism, solar activity......, dustiness, and biomass burning, among others. In Antarctica, ice cores extend back more than 800,000 years before present (Jouzel et al. 2007), whereas. Greenland ice cores cover the last 130,000 years...

  2. Ice cores

    DEFF Research Database (Denmark)

    Svensson, Anders

    2014-01-01

    Ice cores from Antarctica, from Greenland, and from a number of smaller glaciers around the world yield a wealth of information on past climates and environments. Ice cores offer unique records on past temperatures, atmospheric composition (including greenhouse gases), volcanism, solar activity......, dustiness, and biomass burning, among others. In Antarctica, ice cores extend back more than 800,000 years before present (Jouzel et al. 2007), whereas. Greenland ice cores cover the last 130,000 years...

  3. Changing core beliefs with trial-based cognitive therapy may improve quality of life in social phobia: a randomized study

    Directory of Open Access Journals (Sweden)

    Vania Bitencourt Powell

    2013-09-01

    Full Text Available Objective: To determine whether there are differences in quality of life (QoL improvement after treatment with the trial-based thought record (TBTR versus conventional cognitive therapy (CCT in patients with social anxiety disorder (SAD. Method: A randomized trial comparing TBTR with a set of CCT techniques, which included the standard 7-column dysfunctional thought record (DTR and the positive data log (PDL in patients with SAD, generalized type. Results: Repeated measures analysis of variance (ANOVA revealed a significant time effect in the general health, vitality, social functioning, and mental health domains of the Short Form 36. It also indicated significant treatment effects on the bodily pain, social functioning, role-emotional, and mental health domains, with higher scores in the TBTR group. One-way analysis of covariance (ANCOVA, using pretreatment values as covariates, showed that TBTR was associated with significantly better QoL post-treatment (bodily pain, social functioning and role-emotional and at follow-up (role-emotional. A significant treatment effect on the role-emotional domain at 12-month follow-up denoted a sustained effect of TBTR relative to CCT. Conclusion: This study provided preliminary evidence that TBTR is at least as effective as CCT in improving several domains of QoL in SAD, specifically when the standard 7-column DTR and the PDL are used.

  4. The effect of additional core stability exercises on improving dynamic sitting balance and trunk control for subacute stroke patients: a randomized controlled trial.

    Science.gov (United States)

    Cabanas-Valdés, Rosa; Bagur-Calafat, Caritat; Girabent-Farrés, Montserrat; Caballero-Gómez, Fernanda Mª; Hernández-Valiño, Montserrat; Urrútia Cuchí, Gerard

    2016-10-01

    To examine the effect of core stability exercises on trunk control, dynamic sitting and standing balance, gait, and activities of daily living in subacute stroke patients. A randomized controlled trial. Inpatient rehabilitation hospital in two centres. Eighty patients (mean of 23.25 (±16.7) days post-stroke) were randomly assigned to an experimental group and a control group. Both groups underwent conventional therapy for five days/week for five weeks and the experimental group performed core stability exercises for 15 min/day. The patients were assessed before and after intervention. The Trunk Impairment Scale (Spanish-Version) and Function in Sitting Test were used to measure the primary outcome of dynamic sitting balance. Secondary outcome measures were standing balance and gait as evaluated via Berg Balance Scale, Tinetti Test, Brunel Balance Assessment, Postural Assessment Scale for Stroke (Spanish-Version), and activities of daily living using Barthel Index. The experimental group showed statistically significant differences for all of the total scale scores (PCore stability exercises in addition to conventional therapy improves trunk control, dynamic sitting balance, standing balance, gait and activities of daily living in subacute post-stroke patients. © The Author(s) 2015.

  5. Improving Photovoltaic Performance of the Linear A-Ar-A-type Small Molecules with Diketopyrropyrrole Arms by Tuning the Linkage Position of the Anthracene Core.

    Science.gov (United States)

    Duan, Xiongwei; Xiao, Manjun; Chen, Jianhua; Wang, Xiangdong; Peng, Wenhong; Duan, Linrui; Tan, Hua; Lei, Gangtie; Yang, Renqiang; Zhu, Weiguo

    2015-08-26

    Two isomeric A-Ar-A-type small molecules of DPP2An(9,10) and DPP2An(2,6), were synthesized with two acceptor arms of diketopyrropyrroles (DPP) and a planar aryl hydrocarbon core of the different substituted anthracene (An), respectively. Their thermal stability, crystallinity, optoelectronic, and photovoltaic performances were investigated. Significantly red-shifted absorption profile and higher HOMO level were observed for the DPP2An(2,6) with 2,6-substituted anthracene relative to the DPP2An(9,10) with 9,10-substituted anthracene, as the former exhibited better planarity and a larger conjugate system. As a result, the solution-processing solar cells based on DPP2An(2,6) and PC71BM (w/w,1:1) displayed remarkably increased power conversion efficiency of 5.44% and short-circuit current density (Jsc) of 11.90 mA/cm(2) under 1% 1,8-diiodooctane additive. The PCE and Jsc values were 3.7 and 2.9 times those of the optimized DPP2An(9,10)-based cells, respectively. This work demonstrates that changing the linkage position of the anthracene core in the A-Ar-A-type SMs can strongly improve the photovoltaic properties in organic solar cells.

  6. Significantly improved charge collection and interface injection in 3D BiVO4 based multilayered core-shell nanowire photocatalysts.

    Science.gov (United States)

    Zhang, Zemin; Li, Yunxia; Jiang, Xiao; Han, Weihua; Xie, Mingzheng; Wang, Fangcong; Xie, Erqing

    2017-09-11

    It is challenging to design a photocatalyst with high-efficiency light absorption, charge separation and even high-efficiency charge transfer. Here, we report a demonstration by utilizing a three-dimensional multilayered core-shell nanowire array (rGO-ITO@BiVO4) as the composite photocatalyst. The core-shell structure can shorten the length of charge transfer and enhance light absorption through multireflection. RGO with defects can work as the charge transfer medium to improve the hole injection from semiconductor to electrolyte. Associated with the above effects, the Co-pi electrocatalyst modified rGO-ITO@BiVO4 photocatalyst yields a photocurrent of about 6.0 mA cm(-2) at 0.6 V vs. Ag/AgCl. Transient-state surface photovoltage measurement shows that the rGO layer can prolong the lifetime of the photogenerated holes through π-π interactions, so that more holes can participate in the water oxidation reaction.

  7. Determination of lead isotopes in a new Greenland deep ice core at the sub-picogram per gram level by thermal ionization mass spectrometry using an improved decontamination method.

    Science.gov (United States)

    Han, Changhee; Burn-Nunes, Laurie J; Lee, Khanghyun; Chang, Chaewon; Kang, Jung-Ho; Han, Yeongcheol; Hur, Soon Do; Hong, Sungmin

    2015-08-01

    An improved decontamination method and ultraclean analytical procedures have been developed to minimize Pb contamination of processed glacial ice cores and to achieve reliable determination of Pb isotopes in North Greenland Eemian Ice Drilling (NEEM) deep ice core sections with concentrations at the sub-picogram per gram level. A PL-7 (Fuso Chemical) silica-gel activator has replaced the previously used colloidal silica activator produced by Merck and has been shown to provide sufficiently enhanced ion beam intensity for Pb isotope analysis for a few tens of picograms of Pb. Considering the quantities of Pb contained in the NEEM Greenland ice core and a sample weight of 10 g used for the analysis, the blank contribution from the sample treatment was observed to be negligible. The decontamination and analysis of the artificial ice cores and selected NEEM Greenland ice core sections confirmed the cleanliness and effectiveness of the overall analytical process.

  8. Tretinoin-loaded lipid-core nanocapsules decrease reactive oxygen species levels and improve bovine embryonic development during in vitro oocyte maturation.

    Science.gov (United States)

    Lucas, Caroline Gomes; Remião, Mariana Härter; Komninou, Eliza Rossi; Domingues, William Borges; Haas, Cristina; Leon, Priscila Marques Moura de; Campos, Vinicius Farias; Ourique, Aline; Guterres, Silvia S; Pohlmann, Adriana R; Basso, Andrea Cristina; Seixas, Fabiana Kömmling; Beck, Ruy Carlos Ruver; Collares, Tiago

    2015-12-01

    In vitro oocyte maturation (IVM) protocols can be improved by adding chemical supplements to the culture media. Tretinoin is considered an important retinoid in embryonic development and its association with lipid-core nanocapsules (TTN-LNC) represents an innovative way of improving its solubility, and chemical stability, and reducing its toxicity. The effects of supplementing IVM medium with TTN-LNC was evaluated by analyzing production of reactive oxygen species (ROS), S36-phosphorilated-p66Shc levels and caspase activity in early embryonic development, and expression of apoptosis and pluripotency genes in blastocysts. The lowest concentration tested (0.25μM) of TTN-LNC generated higher blastocyst rate, lower ROS production and S36-p66Shc amount. Additionally, expression of BAX and SHC1 were lower in both non-encapsulated tretinoin (TTN) and TTN-LNC-treated groups. Nanoencapsulation allowed the use of smaller concentrations of tretinoin to supplement IVM medium thus reducing toxic effects related with its use, decreasing ROS levels and apoptose frequency, and improving the blastocyst rates.

  9. THE RELATION BETWEEN COOL CLUSTER CORES AND HERSCHEL-DETECTED STAR FORMATION IN BRIGHTEST CLUSTER GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Rawle, T. D.; Egami, E.; Rex, M.; Fiedler, A.; Haines, C. P.; Pereira, M. J.; Portouw, J.; Walth, G. [Steward Observatory, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721 (United States); Edge, A. C. [Institute for Computational Cosmology, Durham University, South Road, Durham DH1 3LE (United Kingdom); Smith, G. P. [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Altieri, B.; Valtchanov, I. [Herschel Science Centre, ESAC, ESA, P.O. Box 78, Villanueva de la Canada, 28691 Madrid (Spain); Perez-Gonzalez, P. G. [Departamento de Astrofisica, Facultad de CC. Fisicas, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Van der Werf, P. P. [Sterrewacht Leiden, Leiden University, P.O. Box 9513, 2300 RA, Leiden (Netherlands); Zemcov, M., E-mail: trawle@as.arizona.edu [Department of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States)

    2012-03-01

    We present far-infrared (FIR) analysis of 68 brightest cluster galaxies (BCGs) at 0.08 < z < 1.0. Deriving total infrared luminosities directly from Spitzer and Herschel photometry spanning the peak of the dust component (24-500 {mu}m), we calculate the obscured star formation rate (SFR). 22{sup +6.2}{sub -5.3}% of the BCGs are detected in the far-infrared, with SFR = 1-150 M{sub Sun} yr{sup -1}. The infrared luminosity is highly correlated with cluster X-ray gas cooling times for cool-core clusters (gas cooling time <1 Gyr), strongly suggesting that the star formation in these BCGs is influenced by the cluster-scale cooling process. The occurrence of the molecular gas tracing H{alpha} emission is also correlated with obscured star formation. For all but the most luminous BCGs (L{sub TIR} > 2 Multiplication-Sign 10{sup 11} L{sub Sun }), only a small ({approx}<0.4 mag) reddening correction is required for SFR(H{alpha}) to agree with SFR{sub FIR}. The relatively low H{alpha} extinction (dust obscuration), compared to values reported for the general star-forming population, lends further weight to an alternate (external) origin for the cold gas. Finally, we use a stacking analysis of non-cool-core clusters to show that the majority of the fuel for star formation in the FIR-bright BCGs is unlikely to originate from normal stellar mass loss.

  10. Young, Star-forming Galaxies and their local Counterparts: the Evolving Relationship of Mass-SFR-Metallicity since z ~ 2.1

    CERN Document Server

    Gebhardt, Henry S Grasshorn; Ciardullo, Robin; Gronwall, Caryl; Hagen, Alex; Bridge, Joanna S; Schneider, Donald P; Trump, Jonathan R

    2015-01-01

    We explore the evolution of the Stellar Mass-Star Formation Rate-Metallicity Relation using a set of 256 COSMOS and GOODS galaxies in the redshift range 1.90 3 . 10^40 ergs s^-1) local galaxies, and this offset cannot be explained by simple systematic offsets in the derived quantities. At stellar masses above ~10^9 Msol and star formation rates above ~10 Msol yr^-1, the z ~ 2.1 galaxies have higher oxygen abundances than their local counterparts, while the opposite is true for lower-mass, lower-SFR systems.

  11. Evaluation of the effect of B and N on the microstructure of 9Cr-2W steel during an aging treatment for SFR fuel cladding tubes

    Science.gov (United States)

    Jeong, Eun Hee; Park, Sang-Gyu; Kim, Sung Ho; Kim, Young Do

    2015-12-01

    In this study, the microstructure of sodium-cooled fast reactor (SFR) fuel cladding steel with different B and N contents after aging is compared. The addition of nitrogen produces a large quantity of MX precipitates with sizes of 0.1 μm or smaller during the initial thermal treatment process and this contributes to help such precipitates maintain stability without being excessively affected by aging. B is primarily distributed in the grain boundary precipitates and grain interior precipitates in the initial stage. The B distribution is believed to move to the Cr precipitates after 7000 h and to contribute to suppressing the growth of M23C6.

  12. Improving accuracy and precision of ice core δD(CH4 analyses using methane pre-pyrolysis and hydrogen post-pyrolysis trapping and subsequent chromatographic separation

    Directory of Open Access Journals (Sweden)

    M. Bock

    2014-07-01

    Full Text Available Firn and polar ice cores offer the only direct palaeoatmospheric archive. Analyses of past greenhouse gas concentrations and their isotopic compositions in air bubbles in the ice can help to constrain changes in global biogeochemical cycles in the past. For the analysis of the hydrogen isotopic composition of methane (δD(CH4 or δ2H(CH4 0.5 to 1.5 kg of ice was hitherto used. Here we present a method to improve precision and reduce the sample amount for δD(CH4 measurements in (ice core air. Pre-concentrated methane is focused in front of a high temperature oven (pre-pyrolysis trapping, and molecular hydrogen formed by pyrolysis is trapped afterwards (post-pyrolysis trapping, both on a carbon-PLOT capillary at −196 °C. Argon, oxygen, nitrogen, carbon monoxide, unpyrolysed methane and krypton are trapped together with H2 and must be separated using a second short, cooled chromatographic column to ensure accurate results. Pre- and post-pyrolysis trapping largely removes the isotopic fractionation induced during chromatographic separation and results in a narrow peak in the mass spectrometer. Air standards can be measured with a precision better than 1‰. For polar ice samples from glacial periods, we estimate a precision of 2.3‰ for 350 g of ice (or roughly 30 mL – at standard temperature and pressure (STP – of air with 350 ppb of methane. This corresponds to recent tropospheric air samples (about 1900 ppb CH4 of about 6 mL (STP or about 500 pmol of pure CH4.

  13. Fuel and Core Design Options to Overcome the Heavy Metal Loading Limit and Improve Performance and Safety of Liquid Salt Cooled Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Petrovic, Bojan [Georgia Inst. of Technology, Atlanta, GA (United States); Maldonado, Ivan [Univ. of Tennessee, Knoxville, TN (United States)

    2016-04-14

    The research performed in this project addressed the issue of low heavy metal loading and the resulting reduced cycle length with increased refueling frequency, inherent to all FHR designs with solid, non-movable fuel based on TRISO particles. Studies performed here focused on AHTR type of reactor design with plate (“plank”) fuel. Proposal to FY12 NEUP entitled “Fuel and Core Design Options to Overcome the Heavy Metal Loading Limit and Improve Performance and Safety of Liquid Salt Cooled Reactors” was selected for award, and the 3-year project started in August 2012. A 4-month NCE was granted and the project completed on December 31, 2015. The project was performed by Georgia Tech (Prof. Bojan Petrovic, PI) and University of Tennessee (Prof. Ivan Maldonado, Co-PI), with a total funding of $758,000 over 3 years. In addition to two Co-PIs, the project directly engaged 6 graduate students (at doctoral or MS level) and 2 postdoctoral researchers. Additionally, through senior design projects and graduate advanced design projects, another 23 undergraduate and 12 graduate students were exposed to and trained in the salt reactor technology. We see this as one of the important indicators of the project’s success and effectiveness. In the process, 1 journal article was published (with 3 journal articles in preparation), together with 8 peer-reviewed full conference papers, 8 peer-reviewed extended abstracts, as well as 1 doctoral dissertation and 2 master theses. The work included both development of models and methodologies needed to adequately analyze this type of reactor, fuel, and its fuel cycle, as well as extensive analyses and optimization of the fuel and core design.

  14. The mass-metallicity relation of zCOSMOS galaxies at z ~ 0.7, its dependence on SFR, and the existence of massive low-metallicity galaxies

    CERN Document Server

    Maier, C; Lilly, S J; Contini, T; Montero, E Perez; Lamareille, F; Bolzonella, M; Floc'h, E Le

    2014-01-01

    (Abridged) The knowledge of the number and of the physical nature of low-metallicity massive galaxies is crucial for the determination and interpretation of the mass-metallicity relation (MZR). Using VLT-ISAAC near-infrared (NIR) spectroscopy of 39 zCOSMOS z~0.7 galaxies, we have measured Halpha and [NII] emission line fluxes for galaxies with [OII], Hbeta and [OIII] available from VIMOS optical spectroscopy. The NIR spectroscopy enables us to break the degeneracy of the R23 method to derive unambiguously O/H gas metallicities, and also SFRs from extinction corrected Halpha. Using, as a benchmark, the position in the D4000 vs. [OIII]/Hbeta diagram of galaxies with reliable O/Hs from NIR spectroscopy, we were able to break the lower/upper branch R23 degeneracy of additional 900 zCOSMOS z~0.7 galaxies. Additionally, the Halpha-based SFR measurements were used to find the best SFR calibration based on [OII] for the zCOSMOS z~0.7 galaxies without Halpha measurements. We find a fraction of 19% of lower mass 9.5<...

  15. Transformer core

    NARCIS (Netherlands)

    Mehendale, A.; Hagedoorn, Wouter; Lötters, Joost Conrad

    2010-01-01

    A transformer core includes a stack of a plurality of planar core plates of a magnetically permeable material, which plates each consist of a first and a second sub-part that together enclose at least one opening. The sub-parts can be fitted together via contact faces that are located on either side

  16. Transformer core

    NARCIS (Netherlands)

    Mehendale, A.; Hagedoorn, Wouter; Lötters, Joost Conrad

    2008-01-01

    A transformer core includes a stack of a plurality of planar core plates of a magnetically permeable material, which plates each consist of a first and a second sub-part that together enclose at least one opening. The sub-parts can be fitted together via contact faces that are located on either side

  17. Potential Improvements of Supercritical CO2 Brayton Cycle by Modifying Critical Point of CO2

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Woo Seok; Lee, Jeong Ik; Jeong, Yong Hoon; No, Hee Cheon [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2009-10-15

    A Sodium-cooled Fast Reactor (SFR) is one of strong candidates for a next generation nuclear reactor. However, the conventional design of a SFR concept with an indirect Rankine cycle is subjected to a sodium water reaction, which can deteriorate the safety of a SFR. To prevent any hazards from sodium-water reaction, a SFR with the Brayton cycle using Helium or Supercritical Carbon dioxide (S-CO2) as working fluids can be an alternative approach to improve the current SFR design. As in a helium cycle, there has been an investigation to modify thermo-physical properties to increase the efficiency of the cycle and reduce the size of turbomachineries. Particularly, He-Xe or He-N2 binary mixture were successful to decrease the stages of turbomachines due to the increment of molecular weight of gas mixture than that of pure helium. Similar to the case of helium, CO2 has a potential to modify its thermo-physical properties by mixing with other gases. For instance, it was reported that critical point of CO2 can be shifted by mixing with different gases. Since, the efficiency of a S-CO2 cycle is limited to the critical point of CO2, the shift in critical point implies that there is a possibility of improving the cycle efficiency than the current design. This paper presents the results of a preliminary analysis to identify the effects of CO2 critical point modification on the Brayton cycle performance.

  18. Improvements in tissue blood flow and lumbopelvic stability after lumbopelvic core stabilization training in patients with chronic non-specific low back pain.

    Science.gov (United States)

    Paungmali, Aatit; Henry, Leonard Joseph; Sitilertpisan, Patraporn; Pirunsan, Ubon; Uthaikhup, Sureeporn

    2016-01-01

    [Purpose] This study investigated the effects of lumbopelvic stabilization training on tissue blood flow changes in the lumbopelvic region and lumbopelvic stability compared to placebo treatment and controlled intervention among patients with chronic non-specific low back pain. [Subjects and Methods] A total of 25 participants (7 males, 18 females; mean age, 33.3 ± 14.4 years) participated in this within-subject, repeated-measures, double-blind, placebo-controlled comparison trial. The participants randomly underwent three types of interventions that included lumbopelvic stabilization training, placebo treatment, and controlled intervention with 48 hours between sessions. Lumbopelvic stability and tissue blood flow were measured using a pressure biofeedback device and a laser Doppler flow meter before and after the interventions. [Results] The repeated-measures analysis of variance results demonstrated a significant increase in tissue blood flow over the lumbopelvic region tissues for post- versus pre-lumbopelvic stabilization training and compared to placebo and control interventions. A significant increase in lumbopelvic stability before and after lumbopelvic stabilization training was noted, as well as upon comparison to placebo and control interventions. [Conclusion] The current study supports an increase in tissue blood flow in the lumbopelvic region and improved lumbopelvic stability after core training among patients with chronic non-specific low back pain.

  19. Design Study and Animation on an Integrated In-Vessel Fuel Handling and Inspection System in a SFR

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. H.; Joo, Y. S.; Lee, J. H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-05-15

    The fuel handling system includes several major components including the rotating plug, in-vessel fuel handling machine, storage rack, cask transporter. The in-vessel fuel handling machine provides access to any core position by means of the eccentric rotating plugs supported in the reactor head. The reactor core and mechanical components which make up the primary circuit coolant are fully immersed in sodium, with the core being up to several meters below the sodium surface. Examination of the internal structure is therefore a difficult task. For example, visual techniques are impossible because of the opacity of liquid metal, and a lowering of the sodium level is impractical once a reactor is operational. In this study, the concept of an integrated fuel handling and inspection machine was suggested to enhance the effectiveness and application of an in-vessel fuel handling machine, and the alternative concept of a specially designed indexing machine has been reviewed and compared. Also, the concept of an integrated in-vessel fuel handling and inspection system was made as a 3D computer graphic animation which is easy to understand the driving characteristics to inform of the design result and verify the design adequacy through the technical consultation of the expert.

  20. SFR inverse modelling Part 2. Uncertainty factors of predicted flow in deposition tunnels and uncertainty in distribution of flow paths from deposition tunnels

    Energy Technology Data Exchange (ETDEWEB)

    Holmen, Johan (Golder Associates, Uppsala (SE))

    2007-10-15

    The Swedish Nuclear Fuel and Waste Management Co (SKB) is operating the SFR repository for low- and intermediate-level nuclear waste. An update of the safety analysis of SFR was carried out by SKB as the SAFE project (Safety Assessment of Final Disposal of Operational Radioactive Waste). The aim of the project was to update the safety analysis and to produce a safety report. The safety report has been submitted to the Swedish authorities. This study is a continuation of the SAFE project, and concerns the hydrogeological modelling of the SFR repository, which was carried out as part of the SAFE project, it describes the uncertainty in the tunnel flow and distributions of flow paths from the storage tunnels. Uncertainty factors are produced for two different flow situations, corresponding to 2,000 AD (the sea covers the repository) and 4,000 AD (the sea has retreated form the repository area). Uncertainty factors are produced for the different deposition tunnels. The uncertainty factors are discussed in Chapter 2 and two lists (matrix) of uncertainty factors have been delivered as a part of this study. Flow paths are produced for two different flow situations, corresponding to 2,000 AD (the sea covers the repository) and 5,000 AD (the sea has retreated form the repository area). Flow paths from the different deposition tunnels have been simulated, considering the above discussed base case and the 60 realisation that passed all tests of this base case. The flow paths are presented and discussed in Chapter 3 and files presenting the results of the flow path analyses have been delivered as part of this study. The uncertainty factors (see Chapter 2) are not independent from the flow path data (see Chapter 3). When stochastic calculations are performed by use of a transport model and the data presented in this study is used as input to such calculations, the corresponding uncertainty factors and flow path data should be used. This study also includes a brief discussion of

  1. Ice Cores

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past temperature, precipitation, atmospheric trace gases, and other aspects of climate and environment derived from ice cores drilled on glaciers and ice...

  2. Core BPEL

    DEFF Research Database (Denmark)

    Hallwyl, Tim; Højsgaard, Espen

    extensions. Combined with the fact that the language definition does not provide a formal semantics, it is an arduous task to work formally with the language (e.g. to give an implementation). In this paper we identify a core subset of the language, called Core BPEL, which has fewer and simpler constructs......, does not allow omissions, and does not contain ignorable elements. We do so by identifying syntactic sugar, including default values, and ignorable elements in WS-BPEL. The analysis results in a translation from the full language to the core subset. Thus, we reduce the effort needed for working...... formally with WS-BPEL, as one, without loss of generality, need only consider the much simpler Core BPEL. This report may also be viewed as an addendum to the WS-BPEL standard specification, which clarifies the WS-BPEL syntax and presents the essential elements of the language in a more concise way...

  3. Core BPEL

    DEFF Research Database (Denmark)

    Hallwyl, Tim; Højsgaard, Espen

    extensions. Combined with the fact that the language definition does not provide a formal semantics, it is an arduous task to work formally with the language (e.g. to give an implementation). In this paper we identify a core subset of the language, called Core BPEL, which has fewer and simpler constructs......, does not allow omissions, and does not contain ignorable elements. We do so by identifying syntactic sugar, including default values, and ignorable elements in WS-BPEL. The analysis results in a translation from the full language to the core subset. Thus, we reduce the effort needed for working...... formally with WS-BPEL, as one, without loss of generality, need only consider the much simpler Core BPEL. This report may also be viewed as an addendum to the WS-BPEL standard specification, which clarifies the WS-BPEL syntax and presents the essential elements of the language in a more concise way...

  4. Core benefits

    National Research Council Canada - National Science Library

    Keith, Brian W

    2010-01-01

    This SPEC Kit explores the core employment benefits of retirement, and life, health, and other insurance -benefits that are typically decided by the parent institution and often have significant governmental regulation...

  5. Evaluation of the effect of B and N on the microstructure of 9Cr–2W steel during an aging treatment for SFR fuel cladding tubes

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Eun Hee [Hanyang University, Department Materials Science and Engineering, 222, Wangsimni-ro, Seongdong-gu, Seoul, 133-791 (Korea, Republic of); Park, Sang-Gyu; Kim, Sung Ho [KAERI, Advanced Fuel Development Division, 989-111 Daedeok-daero, Yuseong-gu, Daejeon, 305-353 (Korea, Republic of); Kim, Young Do, E-mail: ydkim1@hanyang.ac.kr [Hanyang University, Department Materials Science and Engineering, 222, Wangsimni-ro, Seongdong-gu, Seoul, 133-791 (Korea, Republic of)

    2015-12-15

    In this study, the microstructure of sodium-cooled fast reactor (SFR) fuel cladding steel with different B and N contents after aging is compared. The addition of nitrogen produces a large quantity of MX precipitates with sizes of 0.1 μm or smaller during the initial thermal treatment process and this contributes to help such precipitates maintain stability without being excessively affected by aging. B is primarily distributed in the grain boundary precipitates and grain interior precipitates in the initial stage. The B distribution is believed to move to the Cr precipitates after 7000 h and to contribute to suppressing the growth of M{sub 23}C{sub 6}.

  6. Hydrogeological flux scenarios at Forsmark. Generic numerical flow simulations and compilation of climatic information for use in the safety analysis SFR1 SAR-08

    Energy Technology Data Exchange (ETDEWEB)

    Vidstrand, Patrik (Bergab, Goeteborg (SE)); Naeslund, Jens-Ove (Swedish Nuclear Fuel and Waste Management Co., Stockholm (SE)); Hartikainen, Juha (Helsinki Univ. of Technology, Helsinki (FI)); Svensson, Urban (CFE AB, Karlskrona (SE))

    2007-11-15

    In the earlier modelling for SFR-SAFE it was concluded that the groundwater flow would increase with time along with the shoreline displacement. Even though the numerical results are different the same conclusion is drawn after this study. General conclusions from the present study are that: The upper boundary conditions have a significant impact on the groundwater flow in the geosphere. The characteristic of the surface in regards of being a recharge or discharge area affects the results. In general, a discharge area will experience an increase in groundwater flow under changed conditions. The presence of caging fracture zones affects the results, and, for the tested un-frozen SFR situation, the resulting effect is an increase in groundwater flow. Specific conclusions regarding the relative change of groundwater flow due to different surface conditions are that: The permafrost scenarios, along with the development from sporadic permafrost to continuous permafrost, yield increased groundwater flows in unfrozen parts of the domain. The increase is one order of magnitude or less. In the permafrost, the flow is negligible. The ice sheet scenarios yield situations with significantly increased groundwater flow. The results indicate an increase by two to three orders of magnitude. These increased values, however, apply only for short duration intervals. It is possible that such intervals may be only a couple of years. In the selected climate Base variant, repeating the conditions for the last glacial cycle, permafrost conditions occur after 8,000 years. In the climate variant affected by increased greenhouse warming, permafrost conditions do not occur until after more than 50,000 years. In the chosen climate variants, ice sheets reach the Forsmark area and cause significantly increased groundwater flow, after approx60,000 years or more

  7. Tensile property improvement of TWIP-cored three-layer steel sheets fabricated by hot-roll-bonding with low-carbon steel or interstitial-free steel

    OpenAIRE

    Park, Jaeyeong; Kim, Jung-Su; Kang, Minju; Sohn, Seok Su; Cho, Won Tae; Kim, Hyoung Seop; Lee, Sunghak

    2017-01-01

    TWIP-cored three-layer steel sheets were newly fabricated by hot rolling of TWIP steel sheet surrounded by low-carbon (LC) or interstitial-free (IF) steel sheets. TWIP/LC or TWIP/IF interfaces were well bonded without pores or voids, while a few pearlites were thinly formed along the interfaces. The strengths and elongation of the TWIP-cored sheets increased as the volume fraction of TWIP-cored region increased, and were also well matched with the ones calculated by a rule of mixtures based o...

  8. Producing gapped-ferrite transformer cores

    Science.gov (United States)

    Mclyman, W. T.

    1980-01-01

    Improved manufacturing techniques make reproducible gaps and minimize cracking. Molded, unfired transformer cores are cut with thin saw and then fired. Hardened semicircular core sections are bonded together, placed in aluminum core box, and fluidized-coated. After winding is run over box, core is potted. Economical method significantly reduces number of rejects.

  9. Optimal Implantation Depth and Adherence to Guidelines on Permanent Pacing to Improve the Results of Transcatheter Aortic Valve Replacement With the Medtronic CoreValve System: The CoreValve Prospective, International, Post-Market ADVANCE-II Study.

    Science.gov (United States)

    Petronio, Anna S; Sinning, Jan-Malte; Van Mieghem, Nicolas; Zucchelli, Giulio; Nickenig, Georg; Bekeredjian, Raffi; Bosmans, Johan; Bedogni, Francesco; Branny, Marian; Stangl, Karl; Kovac, Jan; Schiltgen, Molly; Kraus, Stacia; de Jaegere, Peter

    2015-05-01

    The aim of the CoreValve prospective, international, post-market ADVANCE-II study was to define the rates of conduction disturbances and permanent pacemaker implantation (PPI) after transcatheter aortic valve replacement with the Medtronic CoreValve System (Minneapolis, Minnesota) using optimized implantation techniques and application of international guidelines on cardiac pacing. Conduction disturbances are a frequent complication of transcatheter aortic valve replacement. The rates of PPI in the published reports vary according to bioprosthesis type and the indications for PPI. The primary endpoint was the 30-day incidence of PPI with Class I/II indications when the Medtronic CoreValve System was implanted at an optimal depth (≤6 mm below the aortic annulus). The timing and resolution of all new-onset conduction disturbances were analyzed. A total of 194 patients were treated. The overall rate of PPI for Class I/II indications was 18.2%. An optimal depth was reached in 43.2% of patients, with a nonsignificantly lower incidence of PPI in patients with depths ≤6 mm, compared with those with deeper implants (13.3% vs. 21.1%; p = 0.14). In a paired analysis, new-onset left bundle branch block and first-degree atrioventricular block occurred in 45.4% and 39.0% of patients, respectively, and resolved spontaneously within 30 days in 43.2% and 73.9%, respectively. In patients with new PPI, the rate of intrinsic sinus rhythm increased from 25.9% at 7 days to 59.3% at 30 days (p = 0.004). Optimal Medtronic CoreValve System deployment and adherence to international guidelines on cardiac pacing are associated with a lower rate of new PPI after transcatheter aortic valve replacement, compared with results reported in previous studies. (CoreValve Advance-II Study: Prospective International Post-Market Study [ADVANCE II]; NCT01624870). Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  10. Tensile property improvement of TWIP-cored three-layer steel sheets fabricated by hot-roll-bonding with low-carbon steel or interstitial-free steel

    Science.gov (United States)

    Park, Jaeyeong; Kim, Jung-Su; Kang, Minju; Sohn, Seok Su; Cho, Won Tae; Kim, Hyoung Seop; Lee, Sunghak

    2017-01-01

    TWIP-cored three-layer steel sheets were newly fabricated by hot rolling of TWIP steel sheet surrounded by low-carbon (LC) or interstitial-free (IF) steel sheets. TWIP/LC or TWIP/IF interfaces were well bonded without pores or voids, while a few pearlites were thinly formed along the interfaces. The strengths and elongation of the TWIP-cored sheets increased as the volume fraction of TWIP-cored region increased, and were also well matched with the ones calculated by a rule of mixtures based on volume fraction or force fraction. According to digital image correlation and electron back-scatter diffraction analyses, very high strain hardening effect in the initial deformation stage and active twin formation in the interfacial region beneficially affected the overall homogeneous deformation in the TWIP-cored sheets without any yield point phenomenon occurring in the LC sheet and serrations occurring in the TWIP sheet, respectively. These TWIP-cored sheets can cover a wide range of yield strength, tensile strength, and ductility levels, e.g., 320~498 MPa, 545~878 MPa, and 48~54%, respectively, by controlling the volume fraction of TWIP-cored region, and thus present new applications to multi-functional automotive steel sheets requiring excellent properties. PMID:28067318

  11. Tensile property improvement of TWIP-cored three-layer steel sheets fabricated by hot-roll-bonding with low-carbon steel or interstitial-free steel

    Science.gov (United States)

    Park, Jaeyeong; Kim, Jung-Su; Kang, Minju; Sohn, Seok Su; Cho, Won Tae; Kim, Hyoung Seop; Lee, Sunghak

    2017-01-01

    TWIP-cored three-layer steel sheets were newly fabricated by hot rolling of TWIP steel sheet surrounded by low-carbon (LC) or interstitial-free (IF) steel sheets. TWIP/LC or TWIP/IF interfaces were well bonded without pores or voids, while a few pearlites were thinly formed along the interfaces. The strengths and elongation of the TWIP-cored sheets increased as the volume fraction of TWIP-cored region increased, and were also well matched with the ones calculated by a rule of mixtures based on volume fraction or force fraction. According to digital image correlation and electron back-scatter diffraction analyses, very high strain hardening effect in the initial deformation stage and active twin formation in the interfacial region beneficially affected the overall homogeneous deformation in the TWIP-cored sheets without any yield point phenomenon occurring in the LC sheet and serrations occurring in the TWIP sheet, respectively. These TWIP-cored sheets can cover a wide range of yield strength, tensile strength, and ductility levels, e.g., 320~498 MPa, 545~878 MPa, and 48~54%, respectively, by controlling the volume fraction of TWIP-cored region, and thus present new applications to multi-functional automotive steel sheets requiring excellent properties.

  12. VLT-SINFONI sub-kpc study of the star formation in local LIRGs and ULIRGs: Analysis of the global $\\Sigma_{\\rm SFR}$ structure and characterisation of individual star-forming clumps

    CERN Document Server

    López, Javier Piqueras; Arribas, Santiago; Pereira-Santaella, Miguel; Alonso-Herrero, Almudena

    2016-01-01

    We present a 2D study of star formation at kpc and sub-kpc scales of a sample of local (z<0.1) U/LIRGs, based on near-IR VLT-SINFONI observations. We obtained integrated measurements of the star formation rate (SFR) and star formation rate surface density, together with their 2D distributions, based on Br_gamma and Pa_alpha emission. We observe a tight linear correlation between the SFR derived from our extinction-corrected measurements and that derived from 24 micron data, and a reasonable agreement with SFR derived from total IR luminosity. Our near-IR measurements are on average a factor 3 larger than optical SFR, even when extinction corrections are applied. We found that LIRGs have a median-observed star formation rate surface density of 1.72 Msun/yr/kpc^2 for the extinction-corrected distribution, whilst ULIRGs have 0.23 Msun/yr/kpc^2, respectively. These median values for ULIRGs increase up to 2.90 Msun/yr/kpc^2, when only their inner regions, covering the same size as the average FoV of LIRGs, are ...

  13. 滨海新区钻探取芯技术的改良及应用%Improvement and application of core-drilling technique in Binhai new area

    Institute of Scientific and Technical Information of China (English)

    齐波; 牛文明; 张一飞

    2011-01-01

    阐述了滨海新区的地层结构特征,分析了该区域常规地质钻探取芯工艺的现状,指出目前普遍采用的单管干钻投球取芯法存在的问题是岩芯采取率低、原状土样扰动严重。以滨海新区某1200m超深地质钻孔施工为例,研究总结了该钻孔为提高钻探质量所进行的系列技术改良,详细分析了为提高岩芯采取率、减少土样扰动而进行的钻具异径接头、钻头及岩芯保护罩的改进,并就应用效果与常规的钻探取芯方法进行比较,分析认为这种改进使钻探取芯质量得到了有效提高,改进效果良好。%The stratigraphic characteristics and the conventional geological coring drilling technique in Binhai new area are elaborated.It is pointed out that the problem existed in the single-pipe dry drilling pitch which is commonly used is the low percentage of core recovery,which seriously disturbs the undisturbed soil samples.Taking the super deep geological drilling which is 1200m depth in Binhai new area as an example,a series of technical improvement for improving the quality of the drilling are studied and summarized.The improvement for the different diameter connector of drilling tool,the bit and the core shield is analyzed in detail,which improves the percentage of core recovery and decreases the disturbance to soil samples.The application effect of the improved technique is compared with that of the conventional core-drilling technique.It is believed that the quality of the core drilling has been effectively improved,and the technical improvement has gotten good application results.

  14. 病区护士长在提高护理核心制度执行力中的作用%Effect of head nurse in improving nursing core system excuion

    Institute of Scientific and Technical Information of China (English)

    陈继梅

    2012-01-01

    目的:提高核心制度执行力.方法:结合科室具体特点(人员结构、病人特点、需求),将核心制度构造在具体的业务流程中,便于督导执行和量化考核.结果:执行护理核心制度成为护士的习惯行为.结论:为了方便所有护理人员准确执行核心制度,应将核心制度构造在具体的业务流程中,并构造好流程的所有环节.%Objective: To improve the execution of the core system. Methods: the specific characteristics of the department ( staff structure, patient characteristics, needs) , the core system constructed in specific business processes to facilitate the supervision of the implementation and quantitative evaluation. Resists; The implementation of the nursing core system to become nurses in the habit of behavior. Conclusion: In order to facilitate all nurses to perform the core system, the core system should be constructed in a specific business process, and construct all aspects of the process.

  15. An upconversion NaYF4:Yb3+,Er3+/TiO2 core-shell nanoparticle photoelectrode for improved efficiencies of dye-sensitized solar cells

    Science.gov (United States)

    Zhang, Jun; Shen, Haiou; Guo, Wei; Wang, Shunhao; Zhu, Chuntao; Xue, Fang; Hou, Jinfeng; Su, Haiquan; Yuan, Zhuobin

    2013-03-01

    Novel upconversion NaYF4:Yb3+,Er3+/TiO2 core-shell nanoparticles (NPs) are synthesized and used to prepare the photoelectrode (PE) of dye-sensitized solar cells (DSSCs). The morphology, structure, photoluminescence characterization of the NaYF4:Yb3+,Er3+/TiO2 core-shell NPs and the photoelectric performance, alternating current impedance spectroscopy of DSSCs are characterized using transmission electron microscopy, X-ray diffraction, upconversion luminescence (UCL) spectrofluorimetry and electrochemistry. Compared with the pure TiO2 PE or the NaYF4:Yb3+,Er3+ upconversion NPs and TiO2 simply mixed prepared PE as the volume ratio of the core-shell structure, the DSSCs with the upconversion core-shell PE show a greater photovoltaic efficiency. The energy conversion efficiency of the DSSCs with a NaYF4:Yb3+,Er3+/TiO2 PE is 23.1% higher than with a pure TiO2 PE and 99.1% higher than with a mixed PE using the same conditions. This enhancement is due to the UCL core extending the spectral response range of DSSCs to the infrared region and their particular shell structure, retaining its semiconductor character. This method represents a novel approach to increase the efficiencies of DSSCs.

  16. 对某产品芯轴整体镀金工艺改进%To Improve a Product Core Shaft Overall Gold Plating Process

    Institute of Scientific and Technical Information of China (English)

    仲志新; 董铭江; 李建华; 范筱琳

    2015-01-01

    阐述了旋转开关式环位置传感器产品的芯轴在电镀过程中出现的问题及解决方法。为了起到良好的导电性和耐磨性,该部件要求在外圆金属表面进行 Cu/Ep·Ni1~3Au3~5hd 表面处理工艺。在实现这一表面处理过程中出现了很多的问题,电镀的合格率最初不足10%,且由于该部件要求导电环表面高出填料表面0~0.01 mm,给产品的电镀、退镀都造成了困难,废品率极高。通过过程监控,发现影响电镀质量的因素是前处理不到位。对电镀的前处理过程进行分析、改进,使部件生产过程及表面处理的前处理过程得到完善,从而提高镀层的外观与结合力,使该部件的电镀合格率由10%提升到80%,提高产品的合格率,完成产品节点交付。%This paper describes a core shaft similar to a rotary switch in a location sensor,de-scribes problems occurring in the product during the plating process and provides a solution to said problem.In order to improve conductibility and abrasion resistance,the part must have an exterior metal surface having a Cu/Ep ·Ni1 ~3Au3 ~5hd surface treatment.A number of problems emerged during surface treatment process,and the pass rate of plating was initially less than 10%.The high requirements for the filling surface of the conduct ring,between 0 and 0.01 mm,made it difficult to manufacture the plate and the back plate.As a re-sult,a high percentage of products were rejected. By conducting process monitoring,we found a key factor affecting the plating quality was insufficient pre treatment.By conducting analysis and impro-ving the plating pre treatment process,the parts manufacturing process and the surface treatment process was perfected.Thus the appearance and binding force of coating was improved,and the pass rate of plating parts increased from 10% to 80%,so that more products could be successfully delivered.

  17. Self powered neutron detectors as in-core detectors for Sodium-cooled Fast Reactors

    Science.gov (United States)

    Verma, V.; Barbot, L.; Filliatre, P.; Hellesen, C.; Jammes, C.; Svärd, S. Jacobsson

    2017-07-01

    Neutron flux monitoring system forms an integral part of the design of a Generation IV sodium cooled fast reactor. Diverse possibilities of detector system installation must be studied for various locations in the reactor vessel in order to detect any perturbations in the core. Results from a previous paper indicated that it is possible to detect changes in neutron source distribution initiated by an inadvertent withdrawal of outer control rod with in-vessel fission chambers located azimuthally around the core. It is, however, not possible to follow inner control rod withdrawal and precisely know the location of the perturbation in the core. Hence the use of complimentary in-core detectors coupled with the peripheral fission chambers is proposed to enable robust core monitoring across the radial direction. In this paper, we assess the feasibility of using self-powered neutron detectors (SPNDs) as in-core detectors in fast reactors for detecting local changes in the power distribution when the reactor is operated at nominal power. We study the neutron and gamma contributions to the total output current of the detector modelled with Platinum as the emitter material. It is shown that this SPND placed in an SFR-like environment would give a sufficiently measurable prompt neutron induced current of the order of 600 nA/m. The corresponding induced current in the connecting cable is two orders of magnitude lower and can be neglected. This means that the SPND can follow in-core power fluctuations. This validates the operability of an SPND in an SFR-like environment.

  18. Layer-by-Layer Coating of Solid Drug Cores: A Versatile Method to Improve Stability, Control Release and Tune Surface Properties.

    Science.gov (United States)

    Polomska, Anna; Leroux, Jean-Christophe; Brambilla, Davide

    2017-01-01

    Layer-by-layer coating is a simple and versatile technique based on the sequential deposition of molecular species on planar surfaces or colloidal templates. Its relevance in drug delivery primarily emerges from its versatility to control the release rate of the cargo encapsulated within the colloidal core. The focus of this review is the layer-by-layer encapsulation of colloidal particles purely composed of drug, including the core fabrication step, coating materials and techniques, multilayer shell permeability control, and reported in vitro and in vivo outcomes.

  19. The Innovative Management Strategy of Improving the Core Competence of Enterprises in China%试论提高中国企业核心竞争力的管理创新策略

    Institute of Scientific and Technical Information of China (English)

    李晶

    2012-01-01

    Management and its innovation are important factors in improving the core competence of enterprises. This article aims to explore the strategy of management innovation to improve core competence of enterprises under the background of economic globalization, deepen innovation in marketing and sales management, procurement and supply chain management, human resource management, benchmarking and green management concepts.%管理及其创新是提高企业核心竞争力的重要因素.本文旨在探索经济全球化背景下管理创新对企业核心竞争力提高的策略,深化市场营销和销售管理创新、采购和供应链管理创新、人力资源管理创新、标杆管理和绿色管理等理念.

  20. A transport and fate model of C-14 in a bay of the Baltic Sea at SFR. Today and in future

    Energy Technology Data Exchange (ETDEWEB)

    Kumblad, L. [Stockholm Univ. (Sweden). Dept. of Systems Ecology

    2001-06-01

    The environmental transport and fate of a hypothetical release of radioactive carbon-14 from SFR-1 (the final repository for radioactive operational waste) was investigated using an ecosystem modelling approach. The approach involved identification, quantification and dynamic modelling of the main flows and storages of carbon both in the physical environment and in the food web. Carbon-14 was in the model introduced into the food web via photosynthesising organisms. Contamination of the aquatic ecosystem above SFR-1 was then assessed assuming a release of 5.13 x 10{sup 7} Bq/year for 1,000 years. Modelling results were used to estimate steady-state C-14 concentrations in biota, exposure (Gy) of biota and dose (Sv) to humans consuming contaminated organisms both if the discharge occurred today (2000 AD)and if it occurred in the future (4000 AD). Since the modelled area is characterised by a fast water exchange, most of the discharged C-14 was flushed out of the system more or less immediately (99.8% and 98.4% at 2000 AD and 4000 AD, respectively). However, a small fraction of the discharge was assimilated by primary producers (0.18% and 2.11%), which enabled subsequent transfer of C-14 to organisms at higher trophic levels (e.g. fish, seals and humans). The exported C-14 from the area was diluted to very low concentrations in the large recipient outside. Estimated exposures were very low, and differed significantly among the studied biota (17.2 x 10{sup -12} to 2.3 x 10{sup -6} Gy). In general the highest exposures were observed in benthic plants and benthic grazers followed by fish and benthos. Humans consuming large quantities of locally produced food (e.g.fish, mussels and algae) will receive an exposure in case of C-14 contamination. Estimated doses to humans were approximately 10-100 nSv per year, which is significantly lower than restrictions by the authorities. The developed model was also used to evaluate implications of various assumptions concerning the

  1. A Key to Improved Ion Core Confinement in the JET Tokamak: Ion Stiffness Mitigation due to Combined Plasma Rotation and Low Magnetic Shear

    DEFF Research Database (Denmark)

    Mantica, P.; Challis, C.; Peeters, A.G.

    2011-01-01

    New transport experiments on JET indicate that ion stiffness mitigation in the core of a rotating plasma, as described by Mantica et al. Phys. Rev. Lett. 102 175002 (2009)] results from the combined effect of high rotational shear and low magnetic shear. The observations have important implicatio...

  2. X-ray fluorescence core scanning of wet marine sediments: methods to improve quality and reproducibility of high-resolution paleoenvironmental records

    NARCIS (Netherlands)

    Hennekam, R.; de Lange, G.

    2012-01-01

    X-ray fluorescence (XRF) core-scanning is a convenient non-destructive tool to rapidly assess elemental variations in unprocessed sediments. However, substantial analytical deviations may occur in such data due to physical sedimentary properties. The consequences of these artifacts on element

  3. A novel structural Fenton-like nanocatalyst with highly improved catalytic performance for generalized preparation of iron oxide@organic dye polymer core-shell nanospheres.

    Science.gov (United States)

    Zhao, Guanghui; Peng, Xiaomen; Li, Hongping; Wang, Jianzhi; Zhou, Lincheng; Zhao, Tianqi; Huang, Zhihao; Jiang, Haifei

    2015-05-01

    FexOy@FexOy/C nanoparticles with a soap-bubble-like shell have been synthesized, and the materials exhibit excellent Fenton catalytic performance. More importantly, FexOy@FexOy/C nanoparticles as catalysts and precursors could catalyze organic dye molecules to form iron oxide@organic dye polymer core-shell nanospheres.

  4. Correlation factors for C-14, Cl-36, Ni-59, Ni-63, Mo-93, Tc-99, I-129 and Cs-135. In operational waste for SFR 1

    Energy Technology Data Exchange (ETDEWEB)

    Lindgren, Maria; Pettersson, Michael; Wiborgh, Marie (Kemakta AB, Stockholm (SE))

    2007-01-15

    The use of correlation factors is one possibility to estimate a reference radionuclide inventory for the purpose of safety assessment studies, when waste-type specific information is not at hand. The correlation factor approach requires that there is a correlation between the activity content of the difficult-to-measure nuclide and the key nuclide. A safety assessment of a future deep repository for low and intermediate level waste (SFL 3-5) was conducted during the second half of the 1990's. Within that project, correlation factors for estimating the inventory of radionuclides which are difficult to measure experimentally were developed. These factors have also partly been used to estimate a reference inventory for SFR 1. Based on a literature survey and recent reports published by SKB, it is concluded that new information is available making an update of some correlation factors relevant. For these radionuclides, reported data from estimations and measurements of radionuclide content and correlation factors in different types of radioactive wastes are summarised. The data is evaluated and updated correlation factors representative for fresh waste for eight radionuclides (C-14, Cl-36, Ni-59, Ni-63, Mo-93, Tc-99, I-129 and Cs-135) are suggested. New information from measurements in Swedish NPP has made it possible to define factors that are BWR and PWR specific for C-14, Ni-59 and Ni-63. The uncertainties in suggested data and the applicability of the correlation factors for estimates of the radionuclide content in operational waste are commented upon

  5. Strategies to Improve Core Competitiveness of Independent Colleges%独立学院提高核心竞争力的策略研究

    Institute of Scientific and Technical Information of China (English)

    王德胜; 卢静

    2013-01-01

    At present, the development of China's independent colleges faces a variety of challenge. Only to build the core competitiveness can be invincible. Core competitiveness of independent colleges is a systematic project, and it can be conducted by scientific orienttion, nurturing characteristics, strengthening teacher quality, innovation management, and construction of campus culture and employment guidance.%当前,我国独立学院发展面临多种挑战,只有努力打造核心竞争力才能立于不败之地.独立学院核心竞争力培育是一项系统工程,可通过科学定位、培育特色、强化师资、创新管理、建设校园文化和指导就业等途径进行.

  6. Improvement of the Vertical Spindle Speed Detecting Method for Vertical Spindle-type Core Drill%立轴式岩心钻机转速检测方法的改进

    Institute of Scientific and Technical Information of China (English)

    尹崧宇; 赵大军; 郭威; 孙友宏; 刘华南; 孙梓航

    2013-01-01

    立轴式岩心钻机是岩心钻探工程中应用最广泛的钻机。对立轴式岩心钻机转速检测方法进行改进,并且研制了以传感器、计数器模块和采集机为核心的钻机转速检测系统。对转速检测系统中的计数器模块进行优化设计,提高了转速测量的准确性。经漠河盆地天然气水合物钻探试验井的应用,系统工作准确可靠,满足使用要求。%Spindle-type core drill is the most popular drill in geological core drilling engineering.This article presents the improvement of the vertical spindle speed detecting method for spindle-type core drill and introduces the development of speed detecting system based on the key technologies of the sensor, counter module and acquisition machine.The counter module design is optimized to improve the accuracy of the speed measurement.The system has been examined by the NGH drilling program in Mohe, which can surely meet the requirement.

  7. Improvement of the physical properties of ZnO/CdTe core-shell nanowire arrays by CdCl2 heat treatment for solar cells

    OpenAIRE

    Consonni, Vincent; Renet, Sébastien; Garnier, Jérôme; Gergaud, Patrice; Artús, Lluis; Michallon, Jérôme; Rapenne, Laetitia; Appert, Estelle; Kaminski-Cachopo, Anne

    2014-01-01

    Abstract CdTe is an important compound semiconductor for solar cells, and its use in nanowire-based heterostructures may become a critical requirement, owing to the potential scarcity of tellurium. The effects of the CdCl2 heat treatment are investigated on the physical properties of vertically aligned ZnO/CdTe core-shell nanowire arrays grown by combining chemical bath deposition with close space sublimation. It is found that recrystallization phenomena are induced by the CdCl2 heat treatmen...

  8. Core Journal Lists: Classic Tool, New Relevance

    Science.gov (United States)

    Paynter, Robin A.; Jackson, Rose M.; Mullen, Laura Bowering

    2010-01-01

    Reviews the historical context of core journal lists, current uses in collection assessment, and existing methodologies for creating lists. Outlines two next generation core list projects developing new methodologies and integrating novel information/data sources to improve precision: a national-level core psychology list and the other a local…

  9. Optimized Cellular Core for Rotorcraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Patz Materials and Technologies proposes to develop a unique structural cellular core material to improve mechanical performance, reduce platform weight and lower...

  10. Improved soft magnetic properties in nanocrystalline FeCuNbSiB Nanophy® cores by intense magnetic field annealing

    Science.gov (United States)

    Madugundo, Rajasekhar; Geoffroy, Olivier; Waeckerle, Thierry; Frincu, Bianca; Kodjikian, Stéphanie; Rivoirard, Sophie

    2017-01-01

    The effect of high external magnetic field (up to 7 T) on soft magnetic properties in nanocrystalline Fe74.1Si15.7Nb3.1B6.1Cu1 Nanophy® cores has been investigated. The as-quenched amorphous ribbons were nanocrystallized by annealing between 540 and 620 °C in transverse magnetic field. By varying annealing field from 0 to 7 T, induced anisotropy ranging from as low as 4 J/m3 to as high as 41 J/m3 is obtained. It is responsible for an increase in the cut-off frequency up to 300 kHz when the material is submitted to dynamic magnetic excitations. A minimum coercivity of 0.74 A/m is observed in the core annealed in 1 T associated to low losses. The relative permeability decreases on increasing the annealing field intensity with a minimum value of 13,654 at 7 T. Such permeability level opens the way to new applications of the Nanophy® alloys.

  11. P-si nanowires/n-ZnO thin film based core-shell heterojunction diodes with improved effective Richardson constant.

    Science.gov (United States)

    Hazra, Purnima; Jit, S

    2014-07-01

    This paper reports the temperature dependent electrical parameters of p-Silicon nanowires (SiNWs)/n-ZnO thin film based core-shell heterojunction diodes fabricated by conformally deposited zinc oxide (ZnO) by atomic layer deposition (ALD) technique on metal-assisted chemically etched SiNWs. The temperature-dependent current-voltage characteristics of the device have been estimated using the modified thermionic emission model in which a Gaussian distributed barrier height function is assumed to include the effects of barrier inhomogeneity phenomenon at the p-SiNW /n-ZnO heterojunction interface. Various parameters such as the turn-on voltage, ideality factor (eta), barrier height (phi(b)) and reverse saturation current are estimated over the operating temperature range of 303 K to 423 K of the diode. The value of the Richardson constant is observed to be largely changed from an impractical value of 1.989 x 10(-6) A cm(-2) K-2 to a realistic value of 36.6 A cm(-2) K-2 once the barrier inhogeneity phenomenon is taken into consideration in the analysis. The estimated value of the Richardson constant is believed to be the best among the reported results. The study is also believed to be the first in case of p-SiNWs/n-ZnO core-shell heterojunction diodes.

  12. Item banking to improve, shorten and computerize self-reported fatigue: an illustration of steps to create a core item bank from the FACIT-Fatigue Scale.

    Science.gov (United States)

    Lai, Jin-shei; Cella, David; Chang, Chih-Hung; Bode, Rita K; Heinemann, Allen W

    2003-08-01

    Fatigue is a common symptom among cancer patients and the general population. Due to its subjective nature, fatigue has been difficult to effectively and efficiently assess. Modern computerized adaptive testing (CAT) can enable precise assessment of fatigue using a small number of items from a fatigue item bank. CAT enables brief assessment by selecting questions from an item bank that provide the maximum amount of information given a person's previous responses. This article illustrates steps to prepare such an item bank, using 13 items from the Functional Assessment of Chronic Illness Therapy Fatigue Subscale (FACIT-F) as the basis. Samples included 1022 cancer patients and 1010 people from the general population. An Item Response Theory (IRT)-based rating scale model, a polytomous extension of the Rasch dichotomous model was utilized. Nine items demonstrating acceptable psychometric properties were selected and positioned on the fatigue continuum. The fatigue levels measured by these nine items along with their response categories covered 66.8% of the general population and 82.6% of the cancer patients. Although the operational CAT algorithms to handle polytomously scored items are still in progress, we illustrated how CAT may work by using nine core items to measure level of fatigue. Using this illustration, a fatigue measure comparable to its full-length 13-item scale administration was obtained using four items. The resulting item bank can serve as a core to which will be added a psychometrically sound and operational item bank covering the entire fatigue continuum.

  13. Tailor-made polyfluoroacrylate and its block copolymer by RAFT polymerization in miniemulsion; improved hydrophobicity in the core-shell block copolymer.

    Science.gov (United States)

    Chakrabarty, Arindam; Singha, Nikhil K

    2013-10-15

    Controlled/living radical polymerization (CRP) of a fluoroacrylate was successfully carried out in miniemulsion by Reversible Addition Fragmentation chain Transfer (RAFT) process. In this case, 2,2,3,3,4,4,4-heptafluorobutyl acrylate (HFBA) was polymerized using 2-cyanopropyl dodecyl trithiocarbonate (CPDTC) as RAFT agent, Triton X-405 and sodium dodecyl sulfonate (SDS) as surfactant, and potassium persulphate (KPS) or 2,2'-azobis isobutyronitrile (AIBN) as initiator. Being compatible with hydrophobic fluoroacrylate, this RAFT agent offered very high conversion and good control over the molecular weight of the polymer. The miniemulsion was stable without any costabilizer. The long chain dodecyl group (-C12H25) (Z-group in the RAFT agent) had beneficial effect in stabilizing the miniemulsion. When 2-cyano 2-propyl benzodithioate (CPBD) (Z=-C6H5) was used as RAFT agent, the conversion was less and particle size distribution was very broad. Block copolymerization with butyl acrylate (BA) using PHFBA as macro-RAFT agent showed core-shell morphology with the aggregation of PHFBA segment in the shell. GPC as well as DSC analysis confirmed the formation of block copolymer. The core-shell morphology was confirmed by TEM analysis. The block copolymers (PHFBA-b-PBA) showed significantly higher water contact angle (WCA) showing much better hydrophobicity compared to PHFBA alone.

  14. Distribution of actinides in SFR1; Aktinidfoerdelning i SFR1

    Energy Technology Data Exchange (ETDEWEB)

    Ingemansson, Tor [ALARA Engineering, Skultuna (Sweden)

    2000-02-01

    The amount of actinides in the Swedish repository for intermediate level radioactive wastes has been estimated. The sources for the actinides are mainly the purification filters of the reactors and the used fuel pools. Defect fuel elements are the originating source of the actinides. It is estimated that the 12 Swedish reactors, in total, have had 2.2 kg of fuel dissolved in their systems since start-up. About 880 g of this amount has been brought to the intermediate-level repository.

  15. 3D structure through planting core-shell Si@TiN into an amorphous carbon slag: improved capacity of lithium-ion anodes.

    Science.gov (United States)

    Tu, Jiguo; Zhao, Zuochao; Hu, Liwen; Jiao, Shuqiang; Hou, Jungang; Zhu, Hongmin

    2013-07-07

    A 3D-structured anode material, planting core-shell Si@TiN into an amorphous carbon slag (3D STC), was synthesized via a facile pyrolyzing process in assistance with the low-temperature reduction route in a liquid Na-NH3 system. The as-prepared samples were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, cyclic voltammetry and galvanostatic discharge-charge tests. From morphological analysis, TiN nanoparticles were homogeneously dispersed on the surface of Si to form the Si@TiN core-shell structure, subsequently plating into an amorphous C slag to form the 3D STC composite. The electrochemical capacity of the 3D STC anode was measured at a higher rate of 1 C with the cut-off voltages of 0.01 V and 1.5 V. It was found that the initial charge capacity reached up to 1604.6 mA h g(-1). In particular, the reversible charge capacity was as high as 588.7 mA h g(-1) over 100 cycles, with a small capacity loss of about 0.63% per cycle, exhibiting the excellent cycle stability of the 3D STC anode at the higher rate of 1 C. Furthermore, the reversible capacity of the 3D STC anode decreased from 2048.8 mA h g(-1) to 624.0 mA h g(-1) with increasing the current rate from 0.1 C to 2 C, while it was still maintained at 1419.7 mA h g(-1) as the current rate returned to 0.1 C. Consequentially, the 3D structure with a continuous conductive path could provide facile lithium insertion/extraction and fast electron transfer, making for the high rate capacity and good cycle stability.

  16. An improved flow analysis-ion chromatography method for determination of cationic and anionic species at trace levels in Antarctic ice cores.

    Science.gov (United States)

    Morganti, Andrea; Becagli, Silvia; Castellano, Emiliano; Severi, Mirko; Traversi, Rita; Udisti, Roberto

    2007-11-12

    A method was developed for the quantitative determination of cations and anions in Antarctic ice cores at microgL(-1) and sub-microgL(-1) levels by ion chromatography (IC), after ultra-clean decontamination procedures. Strict manipulation and decontamination procedures were used in sub-sampling, in order to minimise sample contamination. Na+, NH4+, K+, Mg2+ and Ca2+ were determined by 12-min isocratic elution (H2SO4 eluent). Contemporaneously, in a parallel device, F-, MSA (methanesulfonic acid), Cl-, NO3- and SO4(2-) were analysed in a single 12-min run with multiple-step elution using Na2CO3/NaHCO3 as eluent. Melted ice samples were pumped from their still-closed containers (polystyrene accuvettes with polyethylene caps), shared between the two ion chromatographic systems, online filtered (0.45 microm Teflon membrane) and pre-concentrated (anions and cations pre-concentration columns) using a flow analysis system, thus avoiding uptake of contaminants from the laboratory atmosphere. Sensitivity, linear range, reproducibility and detection limit were evaluated for each chemical species. Anion or cation detection limits ranged from 0.01 to 0.15 microgL(-1) by using a relatively small sample volume (1.5 mL). Such values are significantly lower than those reported in literature for almost all the components. These methods were successfully applied to the analysis of cations and anions at trace levels in the Dome C ice core. The composition of the atmospheric aerosol for the last 850 kyr was reconstructed by high-resolution continuous chemical stratigraphies. Concentration trends in the last nine glacial-interglacial climatic cycles were shown and briefly discussed.

  17. Multi-Core Cache Hierarchies

    CERN Document Server

    Balasubramonian, Rajeev

    2011-01-01

    A key determinant of overall system performance and power dissipation is the cache hierarchy since access to off-chip memory consumes many more cycles and energy than on-chip accesses. In addition, multi-core processors are expected to place ever higher bandwidth demands on the memory system. All these issues make it important to avoid off-chip memory access by improving the efficiency of the on-chip cache. Future multi-core processors will have many large cache banks connected by a network and shared by many cores. Hence, many important problems must be solved: cache resources must be allocat

  18. Development and first application of a new tool for the simulation of the initiating phase of a severe accident on SFR

    Science.gov (United States)

    Guyot, M.; Gubernatis, P.; Suteau, C.

    2014-06-01

    In order to improve the safety level of Sodium Fast Reactors, low probability events such as Hypothetical Core Disruptive Accident (HCDA) are analyzed for their potential consequences. The initiating phase of such accidents is of particular interest both for the prevention and the mitigation of routes leading to a large core disruption and recriticalities. Up to now, analysis of the initiating phase of HCDA has been performed with the SAS4A code. The SAS4A accident calculations are based on a multiple-channel approach, which requires that subassemblies or groups of similar subassemblies be represented together as independent channels. The SAS4A severe accident calculation scheme resorts to a simplified treatment in which an average pin is used to represent a channel. A point kinetics model coupled with a feedback reactivity model is also used to provide an estimate of the reactor power level. Both to increase the accuracy and decrease the uncertainties in the prediction of reactor safety margins, a new computational tool is currently under development at CEA Cadarache. The main features of this tool are the ability to provide a detailed sub-channel meshing of the sub-assembly as well as three-dimensional kinetics during severe accident conditions. To fulfill these goals, the fluid-dynamics SIMMER-III code has been coupled to the SNATCH solver using a MPI environment. This coupling allows both to compute the multi-phase and multi-component flows encountered in severe accident conditions and to model the power shape variation during voiding and melting of the different reactor materials. This new calculation scheme relies on a SAS-like multiple-channel treatment, where channel-to-channel heat and momentum exchanges are neglected. In this paper, an overview of the SIMMER-III/SNATCH coupled tool capabilities is provided. A first application of this new tool is also performed and compared with a SAS4A reference calculation. The new SIMMER-III/SNATCH tool proved to be

  19. Use of a small particle solid-core packing for improved efficiency and rapid measurement of sirolimus and everolimus by LC-MS/MS.

    Science.gov (United States)

    Morgan, Phillip; Nwafor, Magnus; Tredger, Mike

    2016-06-01

    Measurement of whole blood sirolimus and everolimus is required in order to optimize patient treatment following solid organ transplant. Assay by LC-MS/MS is increasingly preferred; however efficient use of the instrument and short turnaround times are crucial. Use of a 1.6 µm solid-core packing HPLC column (Cortecs) gave significant increases in efficiency, sensitivity and throughput compared with an existing method, following simple protein precipitation of small-volume (20 μL) whole blood samples. Sirolimus, everolimus and the stable isotopic internal standard ((13) C2 D4 - everolimus) eluted at around 0.8 min, and total analytical run time was 2.2 min, saving almost 4 min per sample compared with an existing method. Within-assay imprecision (CV) was 3.3-8.5%, and between-assay imprecision was 2.2-10.8%. Retrospective assay of external quality assurance samples and comparison of patient samples assayed in parallel showed only small differences (between +6.8 and -1.9%) in results using the Cortecs column when compared with the existing method. No significant interferences or ion suppression were observed. Copyright © 2015 John Wiley & Sons, Ltd.

  20. Improved method for the extraction and chromatographic analysis on a fused-core column of ellagitannins found in oak-aged wine.

    Science.gov (United States)

    Navarro, María; Kontoudakis, Nikolaos; Canals, Joan Miquel; García-Romero, Esteban; Gómez-Alonso, Sergio; Zamora, Fernando; Hermosín-Gutiérrez, Isidro

    2017-07-01

    A new method for the analysis of ellagitannins observed in oak-aged wine is proposed, exhibiting interesting advantages with regard to previously reported analytical methods. The necessary extraction of ellagitannins from wine was simplified to a single step of solid phase extraction (SPE) using size exclusion chromatography with Sephadex LH-20 without the need for any previous SPE of phenolic compounds using reversed-phase materials. The quantitative recovery of wine ellagitannins requires a combined elution with methanol and ethyl acetate, especially for increasing the recovery of the less polar acutissimins. The chromatographic method was performed using a fused-core C18 column, thereby avoiding the coelution of main ellagitannins, such as vescalagin and roburin E. However, the very polar ellagitannins, namely, the roburins A, B and C, still partially coeluted, and their quantification was assisted by the MS detector. This methodology also enabled the analysis of free gallic and ellagic acids in the same chromatographic run. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Dual-core antiresonant hollow core fibers.

    Science.gov (United States)

    Liu, Xuesong; Fan, Zhongwei; Shi, Zhaohui; Ma, Yunfeng; Yu, Jin; Zhang, Jing

    2016-07-25

    In this work, dual-core antiresonant hollow core fibers (AR-HCFs) are numerically demonstrated, based on our knowledge, for the first time. Two fiber structures are proposed. One is a composite of two single-core nested nodeless AR-HCFs, exhibiting low confinement loss and a circular mode profile in each core. The other has a relatively simple structure, with a whole elliptical outer jacket, presenting a uniform and wide transmission band. The modal couplings of the dual-core AR-HCFs rely on a unique mechanism that transfers power through the air. The core separation and the gap between the two cores influence the modal coupling strength. With proper designs, both of the dual-core fibers can have low phase birefringence and short modal coupling lengths of several centimeters.

  2. Advanced Burner Reactor with Breed-and-Burn Thorium Blankets for Improved Economics and Resource Utilization

    OpenAIRE

    Zhang, Guanheng

    2015-01-01

    This study assesses the feasibility of designing Seed and Blanket (S&B) Sodium-cooled Fast Reactor (SFR) to generate a significant fraction of the core power from radial thorium fueled blankets that operate on the Breed-and-Burn (B&B) mode without exceeding the 200 Displacements per Atom (DPA) radiation damage constraint of presently verified cladding materials. The S&B core is designed to have an elongated seed (or “driver”) to maximize the fraction of neutrons that radially leak into the su...

  3. Multiple pre- and post-analytical lean approaches to the improvement of the laboratory turnaround time in a large core laboratory.

    Science.gov (United States)

    Lou, Amy H; Elnenaei, Manal O; Sadek, Irene; Thompson, Shauna; Crocker, Bryan D; Nassar, Bassam A

    2017-10-01

    Core laboratory (CL), as a new business model, facilitates consolidation and integration of laboratory services to enhance efficiency and reduce costs. This study evaluates the impact of total laboratory automation system (TLA), electric track vehicle (ETV) system and auto-verification (AV) of results on overall turnaround time (TAT) (phlebotomy to reporting TAT: PR-TAT) within a CL setting. Mean, median and percentage of outlier (OP) for PR-TAT were compared for pre- and post-CL eras using five representative tests based on different request priorities. Comparison studies were also carried out on the intra-laboratory TAT (in-lab to reporting TAT: IR-TAT) and the delivery TAT (phlebotomy to in-lab TAT: PI-TAT) to reflect the efficiency of the TLA (both before and after introducing result AV) and ETV systems respectively. Median PR-TATs for the urgent samples were reduced on average by 16% across all representative analytes. Median PR-TATs for the routine samples were curtailed by 51%, 50%, 49%, 34% and 22% for urea, potassium, thyroid stimulating hormone (TSH), complete blood count (CBC) and prothrombin time (PT) respectively. The shorter PR-TAT was attributed to a significant reduction of IR-TAT through the TLA. However, the median PI-TAT was delayed when the ETV was used. Application of various AV rules shortened the median IR-TATs for potassium and urea. However, the OP of PR-TAT for the STAT requests exceeding 60min were all higher than those from the pre-CL era. TLA and auto-verification rules help to efficiently manage substantial volumes of urgent and routine samples. However, the ETV application as it stands shows a negative impact on the PR-TAT. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  4. Numerical Study for Turbulent Heat Transfer in Helical Wired Sub-channel Flow Regime of Duct-less Assembly in SFR

    Energy Technology Data Exchange (ETDEWEB)

    You, Byunghyun; Jeong, Yong Hoon [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2014-05-15

    A fuel assembly had hexagonal structure adjacent to 6 fuel assemblies, which influence to the target fuel assembly due to elimination of duct. For calculating the influence, 6 additional channels were generated between the adjacent fuel assemblies and cross flow model was applied to the channels. The adjacent fuel assemblies were analyzed and the results were used in the additional channel as boundary condition of the target fuel assembly. To design the specifications of duct-less assembly, modified or brand-new thermal-hydraulic methodology is needed which is using MATRA-LMR and CFD codes in this study. The MATRA-LMR is a sub-channel analysis code for LMR that has been developed in Korea Atomic Energy Research Institute. It is designed to analyze a fuel assembly with wire-wrap and duct structure. However, the duct-less core is not able to be analyzed by the MATRA-LMR which doesn't consider cross flow between the fuel assemblies and effect of grid spacer. The code need improvement by editing source code to eliminate effect of duct and analyze pressure drop and mixing between the sub-channels caused by grid spacer and cross flow between the fuel assemblies. To validate reformed pressure drop model and cross flow model in MATRA-LMR, CFD analysis is performed. For verifying the results of CFD, LMR subchannel experimental data is benchmarked which is done by ORNL. The verified CFD for thermalhydraulic analysis calculated pressure drop and mixing caused by grid spacer and cross flow between fuel assemblies.

  5. Core stability training for injury prevention.

    Science.gov (United States)

    Huxel Bliven, Kellie C; Anderson, Barton E

    2013-11-01

    Enhancing core stability through exercise is common to musculoskeletal injury prevention programs. Definitive evidence demonstrating an association between core instability and injury is lacking; however, multifaceted prevention programs including core stabilization exercises appear to be effective at reducing lower extremity injury rates. PUBMED WAS SEARCHED FOR EPIDEMIOLOGIC, BIOMECHANIC, AND CLINICAL STUDIES OF CORE STABILITY FOR INJURY PREVENTION (KEYWORDS: "core OR trunk" AND "training OR prevention OR exercise OR rehabilitation" AND "risk OR prevalence") published between January 1980 and October 2012. Articles with relevance to core stability risk factors, assessment, and training were reviewed. Relevant sources from articles were also retrieved and reviewed. Stabilizer, mobilizer, and load transfer core muscles assist in understanding injury risk, assessing core muscle function, and developing injury prevention programs. Moderate evidence of alterations in core muscle recruitment and injury risk exists. Assessment tools to identify deficits in volitional muscle contraction, isometric muscle endurance, stabilization, and movement patterns are available. Exercise programs to improve core stability should focus on muscle activation, neuromuscular control, static stabilization, and dynamic stability. Core stabilization relies on instantaneous integration among passive, active, and neural control subsystems. Core muscles are often categorized functionally on the basis of stabilizing or mobilizing roles. Neuromuscular control is critical in coordinating this complex system for dynamic stabilization. Comprehensive assessment and training require a multifaceted approach to address core muscle strength, endurance, and recruitment requirements for functional demands associated with daily activities, exercise, and sport.

  6. Optical fiber sensor having an active core

    Science.gov (United States)

    Egalon, Claudio Oliveira (Inventor); Rogowski, Robert S. (Inventor)

    1993-01-01

    An optical fiber is provided. The fiber is comprised of an active fiber core which produces waves of light upon excitation. A factor ka is identified and increased until a desired improvement in power efficiency is obtained. The variable a is the radius of the active fiber core and k is defined as 2 pi/lambda wherein lambda is the wavelength of the light produced by the active fiber core. In one embodiment, the factor ka is increased until the power efficiency stabilizes. In addition to a bare fiber core embodiment, a two-stage fluorescent fiber is provided wherein an active cladding surrounds a portion of the active fiber core having an improved ka factor. The power efficiency of the embodiment is further improved by increasing a difference between the respective indices of refraction of the active cladding and the active fiber core.

  7. Animal MRI Core

    Data.gov (United States)

    Federal Laboratory Consortium — The Animal Magnetic Resonance Imaging (MRI) Core develops and optimizes MRI methods for cardiovascular imaging of mice and rats. The Core provides imaging expertise,...

  8. 浅析企业管理者应着力提升的三项核心能力%Analysis of the Three Core Competences the Enterprise Managers Should Improve

    Institute of Scientific and Technical Information of China (English)

    程浩

    2014-01-01

    俗话说“大海航行靠舵手”,一个组织、一个团队的成败,管理者的能力是关键。随着市场经济的快速发展,瞬息万变的市场环境、日益激烈的竞争压力对于每个企业管理者提出了更高的能力要求。要想当一名优秀的企业管理者,就要努力提升自己的核心管理能力,从而领导企业不断提升核心竞争力,赢得市场竞争并实现可持续发展。这些核心管理能力主要包括优秀的判断决策能力、解决具体问题的能力和识人用人的能力。%As the saying goes,"Sailing the seas depends on the helmsman", managers' ability is the key to the success or failure of an organization and a team. With the rapid development of market economy, the rapidly changing market environment and the increasingly fierce competition put forward the higher capacity requirements for each enterprise manager. To be an outstanding enterprise manager, it's necessary to strive to improve the core management competence, lead enterprises to continuously enhance the core competitiveness, win the market competition and realize sustainable development. These core management abilities mainly include the excellent judgment decision-making ability, the ability to solve the specific problem and the general ability to choose and employ talents.

  9. Core Strength Training of Synchronized Swimming to Improve Performance%论核心力量训练对花样游泳运动成绩提高的影响

    Institute of Scientific and Technical Information of China (English)

    刘茹

    2016-01-01

    the synchronized SWIMMING the europeans called water ballet of sports, in our country for 20 years,from the beginning that we understand the synchronized SWIMMING to the developing trend of today,has far exceeded the SYNCHRONIZERS SWIMMING, synchronized SWIMMING) the meaning in English. Synchronized swimming, therefore, the characteristics of this project is changing with the development of the project. So the traditional physical training cannot satisfy the need of the competitive sports, the core strength training has become a synchronized swimming fitness training is very important part of. Core strength is a basic posture and synchronized swimming movement control factors, the stability of the spine, pelvis,maintain the correct body posture, balance coordination, improve the speed of synchronized swimming athletes,strength,water level and so on all has the very vital significance. Because of synchronized swimming movement is cyclical projects, the method of core strength training is mainly aimed at the trunk deep small muscles, under the unbalanced state of various training load. Special physical elements around the synchronized swimming projects, this paper puts forward the basic thought of core training, advice on the basis of the initial diagnosis, training cycle, divided into screening and training methods and determine the load trend,pay attention to the individual athlete.%核心力量是花样游泳基本姿势和动作的控制因素,对稳定脊柱、骨盆,保持正确的身体姿势,协调平衡,提高花样游泳运动员的速度、力度、水位等等都具有很重要的意义。由于花样游泳运动是非周期性项目,核心力量的训练方法主要是针对躯干深层小肌肉,在不平衡的状态下进行各种负荷的训练。围绕花样游泳项目专项体能构成要素,提出核心训练的基本思路,建议在初始诊断的基础上,划分训练周期,筛选训练方法和确定负荷趋势,注重运动员个体化。

  10. 浅析铁路货物运输企业核心竞争力的提高%Study on Improving Core Competitivity of Railway Freight Shipping Enterprises

    Institute of Scientific and Technical Information of China (English)

    兰秀文

    2012-01-01

    通过分析中国铁路货物运输企业发展的优势以及存在问题,从加强铁路区域性网络建设,加快铁路货运行业的商业化进程,扩大铁路货运的市场占有量,实现铁路装备现代化四个方面提出了提高铁路运输企业核心竞争力的对策建议.%In this paper, through analyzing the advantage and weakness of the railway freight shipping enterprises in China, we proposed the countermeasures to improve the core competitivity of the enterprises from the aspects of reinforcing regional railway network construction, speeding up commercialization process of the railway freight shipping industry, expanding the market share of railway freight and realizing railway equipment modernization.

  11. Analysis and Improvement of Power Supply Mode for Coring Shockproof Gamma Tool%取芯用防震伽马仪器电池供电方式分析与改进

    Institute of Scientific and Technical Information of China (English)

    张金贵

    2015-01-01

    文章通过对取芯用防震伽马仪器电池供电方式进行研究分析,对其供电方式容易出现的问题进行了剖析,提出了两种改进方案,在实际应用过程中取得了良好的效果,降低了仪器的故障率。%On the basis of the analysis of battery power supply mode of the coring shockproof gamma tool and the problems occurred easily , two improvement methods are proposed , which has achieved good effect in the application and reduced the failure rate of the tool .

  12. 强化供应链质量管理提高闽东电机产业核心竞争力%Strengthen the SCM, Improve the Core Competitiveness of Mindong Electrical Machines Industr y

    Institute of Scientific and Technical Information of China (English)

    陈姗莲; 崔明琦

    2014-01-01

    Through the analysis about the present situation of Mindong electrical machines industry, based on the theory of supply chain management(SCM), put forward by establishing and perfecting the supply chain of motor product, enhance quality of supply chain management, thus improving the core competitiveness and promote rapid and healthy development of Mindong motor industry.%通过对闽东电机产业现状分析,以供应链管理(SCM)理论为基础,提出通过建立健全电机产品供应链,强化供应链质量管理,从而提高企业核心竞争力,带动闽东电机产业健康快速发展的理念。

  13. CoreDevRec:Automatic Core Member Recommendation for Contribution Evaluation

    Institute of Scientific and Technical Information of China (English)

    蒋竞; 贺佳欢; 陈学渊

    2015-01-01

    The pull-based software development helps developers make contributions flexibly and effciently. Core members evaluate code changes submitted by contributors, and decide whether to merge these code changes into repositories or not. Ideally, code changes are assigned to core members and evaluated within a short time after their submission. However, in reality, some popular projects receive many pull requests, and core members have di昋culties in choosing pull requests which are to be evaluated. Therefore, there is a growing need for automatic core member recommendation, which improves the evaluation process. In this paper, we investigate pull requests with manual assignment. Results show that 3.2%∼40.6% of pull requests are manually assigned to specific core members. To assist with the manual assignment, we propose CoreDevRec to recommend core members for contribution evaluation in GitHub. CoreDevRec uses support vector machines to analyze different kinds of features, including file paths of modified codes, relationships between contributors and core members, and activeness of core members. We evaluate CoreDevRec on 18 651 pull requests of five popular projects in GitHub. Results show that CoreDevRec achieves accuracy from 72.9% to 93.5% for top 3 recommendation. In comparison with a baseline approach, CoreDevRec improves the accuracy from 18.7% to 81.3% for top 3 recommendation. Moreover, CoreDevRec even has higher accuracy than manual assignment in the project TrinityCore. We believe that CoreDevRec can improve the assignment of pull requests.

  14. Site investigation SFR. Hydrochemical characterisation of groundwater in the SFR repository. Sampling and analysis during 2010. Extended investigations in KFR7A: 48.0 to 74.7 m KFR08: 63.0 to 104.0 m and KFR19: 95.6 to 110.0 m

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Kersti (Geosigma AB (Sweden))

    2011-03-15

    This report presents chemistry data from the extended sampling in SFR, performed every five years. The extended sampling yielded groundwater chemistry data in accordance with SKB chemistry class 3, 4 and 5 and included all water bearing borehole sections. Supplementary, more extensive, hydrochemical groundwater investigations were performed in three borehole sections: KFR7A:1 (48.0-74.7 m borehole length; 134.0-134.9 m.b.s.l.), KFR08:1 (63.0-104.0 m borehole length; 91.5-95.1 m.b.s.l.) and KFR19:1 (95.6-110.0 m borehole length; 58.2-54.5 m.b.s.l.) with a second purpose to supply important additional data to the SFR extension project. Samples for chemical analyses (major constituents, trace metals and isotopes) were collected in all three borehole sections and on-line measurements of pH, redox potential (Eh) and water temperature were also performed. The measurements were conducted in a flow through cell at the orifice of the boreholes. In addition, on-line measurements of electrical conductivity (EC) and dissolved oxygen were conducted in KFR19:1. Furthermore, enrichments of humic and fulvic acids for determination of delta13C and 14C in organic material were performed in all three sections and sampling for analyses of dissolved gas was performed in KFR08:1 and KFR19:1. The three borehole sections with redox measurements showed stable water composition during the sampling periods. The chloride concentrations amounted to between 2,790 mg/L (KFR19:1) and 3,670 mg/L (KFR7A:1). All of the measured redox potentials (Eh) reached stable and consistent values (-153 mV in KFR7A:1, -156 mV in KFR08:1 and -168 mV in KFR19:1). All three borehole sections showed relatively high oxygen-18 values indicating a clearly marine origin of the groundwaters. No major changes of the water chemistry in the four boreholes included in the annual hydrochemistry monitoring program have been noticed during 2010. A slow shift towards lower chloride concentrations can be noticed when data for a

  15. Design Principles for Synthesizable Processor Cores

    DEFF Research Database (Denmark)

    Schleuniger, Pascal; McKee, Sally A.; Karlsson, Sven

    2012-01-01

    As FPGAs get more competitive, synthesizable processor cores become an attractive choice for embedded computing. Currently popular commercial processor cores do not fully exploit current FPGA architectures. In this paper, we propose general design principles to increase instruction throughput...... through the use of micro-benchmarks that our principles guide the design of a processor core that improves performance by an average of 38% over a similar Xilinx MicroBlaze configuration....

  16. Subchannel analysis of a small ultra-long cycle fast reactor core

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Han; Kim, Ji Hyun; Bang, In Cheol, E-mail: icbang@unist.ac.kr

    2014-04-01

    Highlights: • The UCFR-100 is small-sized one of 60 years long-life nuclear reactors without refueling. • The design safety limits of the UCFR-100 are evaluated using MATRA-LMR. • The subchannel results are below the safety limits of general SFR design criteria. - Abstract: Thermal-hydraulic evaluation of a small ultra-long cycle fast reactor (UCFR) core is performed based on existing safety regulations. The UCFR is an innovative reactor newly designed with long-life core based on the breed-and-burn strategy and has a target electric power of 100 MWe (UCFR-100). Low enriched uranium (LEU) located at the bottom region of the core play the role of igniter to operate the UCFR for 60 years without refueling. A metallic form is selected as a burning fuel region material after the LEU location. HT-9 and sodium are used as cladding and coolant materials, respectively. In the present study, MATRA-LMR, subchannel analysis code, is used for evaluating the safety design limit of the UCFR-100 in terms of fuel, cladding, and coolant temperature distributions in the core as design criteria of a general fast reactor. The start-up period (0 year of operation), the middle of operating period (30 years of operation), and the end of operating cycle (60 years of operation) are analyzed and evaluated. The maximum cladding surface temperature (MCST) at the BOC (beginning of core life) is 498 °C on average and 551 °C when considering peaking factor, while the MCST at the MOC (middle of core life) is 498 °C on average and 548 °C in the hot channel, respectively, and the MCST at the EOC (end of core life) is 499 °C on average and 538 °C in the hot channel, respectively. The maximum cladding surface temperature over the long cycle is found at the BOC due to its high peaking factor. It is found that all results including fuel rods, cladding, and coolant exit temperature are below the safety limit of general SFR design criteria.

  17. k-core covers and the core

    NARCIS (Netherlands)

    Sanchez-Rodriguez, E.; Borm, Peter; Estevez-Fernandez, A.; Fiestras-Janeiro, G.; Mosquera, M.A.

    2015-01-01

    This paper extends the notion of individual minimal rights for a transferable utility game (TU-game) to coalitional minimal rights using minimal balanced families of a specific type, thus defining a corresponding minimal rights game. It is shown that the core of a TU-game coincides with the core of

  18. Academic Rigor: The Core of the Core

    Science.gov (United States)

    Brunner, Judy

    2013-01-01

    Some educators see the Common Core State Standards as reason for stress, most recognize the positive possibilities associated with them and are willing to make the professional commitment to implementing them so that academic rigor for all students will increase. But business leaders, parents, and the authors of the Common Core are not the only…

  19. k-core covers and the core

    NARCIS (Netherlands)

    Sanchez-Rodriguez, E.; Borm, Peter; Estevez-Fernandez, A.; Fiestras-Janeiro, G.; Mosquera, M.A.

    This paper extends the notion of individual minimal rights for a transferable utility game (TU-game) to coalitional minimal rights using minimal balanced families of a specific type, thus defining a corresponding minimal rights game. It is shown that the core of a TU-game coincides with the core of

  20. Common Core in the Real World

    Science.gov (United States)

    Hess, Frederick M.; McShane, Michael Q.

    2013-01-01

    There are at least four key places where the Common Core intersects with current efforts to improve education in the United States--testing, professional development, expectations, and accountability. Understanding them can help educators, parents, and policymakers maximize the chance that the Common Core is helpful to these efforts and, perhaps…

  1. Common Core in the Real World

    Science.gov (United States)

    Hess, Frederick M.; McShane, Michael Q.

    2013-01-01

    There are at least four key places where the Common Core intersects with current efforts to improve education in the United States--testing, professional development, expectations, and accountability. Understanding them can help educators, parents, and policymakers maximize the chance that the Common Core is helpful to these efforts and, perhaps…

  2. Cool Core Clusters from Cosmological Simulations

    CERN Document Server

    Rasia, E; Murante, G; Planelles, S; Beck, A M; Biffi, V; Ragone-Figueroa, C; Granato, G L; Steinborn, L K; Dolag, K

    2015-01-01

    We present results obtained from a set of cosmological hydrodynamic simulations of galaxy clusters, aimed at comparing predictions with observational data on the diversity between cool-core and non-cool-core clusters. Our simulations include the effects of stellar and AGN feedback and are based on an improved version of the Smoothed-Particle-Hydrodynamics code GADGET-3, which ameliorates gas mixing and better captures gas-dynamical instabilities by including a suitable artificial thermal diffusion. In this Letter, we focus our analysis on the entropy profiles, our primary diagnostic to classify the degree of cool-coreness of clusters, and on the iron profiles. In keeping with observations, our simulated clusters display a variety of behaviors in entropy profiles: they range from steadily decreasing profiles at small radii, characteristic of cool-core systems, to nearly flat core isentropic profiles, characteristic of non cool-core systems. Using observational criteria to distinguish between the two classes of...

  3. Comodules over semiperfect corings

    CERN Document Server

    Caenepeel, S

    2011-01-01

    We discuss when the Rat functor associated to a coring satisfying the left $\\alpha$-condition is exact. We study the category of comodules over a semiperfect coring. We characterize semiperfect corings over artinian rings and over qF-rings.

  4. Coring Sample Acquisition Tool

    Science.gov (United States)

    Haddad, Nicolas E.; Murray, Saben D.; Walkemeyer, Phillip E.; Badescu, Mircea; Sherrit, Stewart; Bao, Xiaoqi; Kriechbaum, Kristopher L.; Richardson, Megan; Klein, Kerry J.

    2012-01-01

    A sample acquisition tool (SAT) has been developed that can be used autonomously to sample drill and capture rock cores. The tool is designed to accommodate core transfer using a sample tube to the IMSAH (integrated Mars sample acquisition and handling) SHEC (sample handling, encapsulation, and containerization) without ever touching the pristine core sample in the transfer process.

  5. Stability Analysis of the EBR-I Mark-II Core Meltdown Accident

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jae-Yong; Kang, Chang Mu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    The purpose of this paper is to analyze the stability of the EBR-I core meltdown accident using the NuSTAB code. The result of NuSTAB analysis is compared with previous stability analysis by Sandmeier using the root locus method. The Experimental Breeder Reactor I (EBR-1) at Argonne National Laboratory was designed to demonstrate fast reactor breeding and to prove the use of liquid-metal coolant for power production and reached criticality in August 1951. The EBR-I reactor was undergoing a series of physics experiments and the Mark-II core was melted accidentally on Nov. 29, 1955. The experiment was going to increase core temperature to 500C to see if the reactor loses reactivity, and scram when the power reached 1500 kW or doubling of fission rate per second. However the operator scrammed with a slow moving control and missed the shutdown by two seconds and caused the core meltdown. The NuSTAB code has an advantage of analyzing space-dependent fast reactors and predicting regional oscillations compared to the point kinetics. Also, NuSTAB can be useful when the coupled neutronic-thermal-hydraulic codes cannot be used for stability analysis. Future work includes analyses of the PGSFR for various operating conditions as well as further validation of the NuSTAB calculations against SFR stability experiments when such experiments become available.

  6. 棒对旋涡星系中央恒星形成的作用%The Effects of Bar Sturcture on the Central sSFR of Spiral Galaxies

    Institute of Scientific and Technical Information of China (English)

    林野

    2014-01-01

    We investigate the effects of bars in spiral galaxies on galaxy central specific Star Formation Rate (sSFR) using a sample of over 9000 spiral galaxies drawn from Sloan Digital Sky Survey, with morphological classifications assigned by visual inspection. Our sample includes three types: none-barred galaxies and galaxies hosting long or short bars, respectively. By identifying star-forming and quiescent population, we find barred spiral galaxies tend to be central quiescent. However, the star-forming barred spiral galaxies tend to have stronger central star forming activities than the unbarred spiral galaxies. In order to find the connection between central sSFR and the presence of a bar within the spiral galaxy, we construct control samples where barred and unbarred ones are closely matched by stellar mass. We then find the same proportion of central quiescent galaxies for barred and unbarred ones. Furthermore, the star-forming barred ones still have stronger central star forming activities than the unbarred ones with the signal mainly coming from the long barred ones. These results demonstrate that bars may have no influence on central star quiescence, but bars can induce the central star formation in their host spiral galaxies where the effect are mainly contributed by long bars.%使用了目前最大的棒旋星系样本之一,着重于研究旋涡星系中央的比恒星形成率(sSFR)和棒结构的关系。我们用lg sSFR =−11 a−1作为星系宁静态和活跃态的分界,统计对比了棒旋星系和非棒旋星系中央的sSFR,发现相对于非棒旋星系,棒旋星系处于中央宁静态的比重更大,而在中央活跃态其恒星形成活动更剧烈。为消除星系样本恒星质量差异对星系中央sSFR统计结果的影响,获得控制样本,使棒旋星系和非棒旋星系具有相同的恒星质量分布。随后发现这两类星系在中央宁静态中的统计差异消失,而在中央活跃态棒旋星系的恒星

  7. Banded transformer cores

    Science.gov (United States)

    Mclyman, C. W. T. (Inventor)

    1974-01-01

    A banded transformer core formed by positioning a pair of mated, similar core halves on a supporting pedestal. The core halves are encircled with a strap, selectively applying tension whereby a compressive force is applied to the core edge for reducing the innate air gap. A dc magnetic field is employed in supporting the core halves during initial phases of the banding operation, while an ac magnetic field subsequently is employed for detecting dimension changes occurring in the air gaps as tension is applied to the strap.

  8. Core-shell GaN-ZnO moth-eye nanostructure arrays grown on a-SiO2/Si (1 1 1) as a basis for improved InGaN-based photovoltaics and LEDs

    Science.gov (United States)

    Rogers, D. J.; Sandana, V. E.; Gautier, S.; Moudakir, T.; Abid, M.; Ougazzaden, A.; Teherani, F. Hosseini; Bove, P.; Molinari, M.; Troyon, M.; Peres, M.; Soares, Manuel J.; Neves, A. J.; Monteiro, T.; McGrouther, D.; Chapman, J. N.; Drouhin, H.-J.; McClintock, R.; Razeghi, M.

    2015-06-01

    Self-forming, vertically-aligned, ZnO moth-eye-like nanoarrays were grown by catalyst-free pulsed laser deposition on a-SiO2/Si (1 1 1) substrates. X-Ray Diffraction (XRD) and Cathodoluminescence (CL) studies indicated that nanostructures were highly c-axis oriented wurtzite ZnO with strong near band edge emission. The nanostructures were used as templates for the growth of non-polar GaN by metal organic vapor phase epitaxy. XRD, scanning electron microscopy, energy dispersive X-ray microanalysis and CL revealed ZnO encapsulated with GaN, without evidence of ZnO back-etching. XRD showed compressive epitaxial strain in the GaN, which is conducive to stabilization of the higher indium contents required for more efficient green light emitting diode (LED) and photovoltaic (PV) operation. Angular-dependent specular reflection measurements showed a relative reflectance of less than 1% over the wavelength range of 400-720 nm at all angles up to 60°. The superior black-body performance of this moth-eye-like structure would boost LED light extraction and PV anti-reflection performance compared with existing planar or nanowire LED and PV morphologies. The enhancement in core conductivity, provided by the ZnO, would also improve current distribution and increase the effective junction area compared with nanowire devices based solely on GaN.

  9. Amostragem de acessos introduzidos e melhorados para composição de uma coleção núcleo de milho Sampling of introduced and improved access to composition of a core collection of corn

    Directory of Open Access Journals (Sweden)

    Ronaldo Rodrigues Coimbra

    2012-03-01

    Full Text Available Visando a amostragem de acessos para comporem uma coleção núcleo de milho, foram amostrados acessos introduzidos e melhorados da Coleção Ativa de Germoplasma da Embrapa Milho e Sorgo, localizada em Sete Lagoas, MG. A estratégia de amostragem utilizada foi baseada em análise multivariada, sendo adotada intensidade de amostragem de 20%. A estratificação dos acesos introduzidos foi realizada principalmente de acordo com o país de origem, local de avaliação e tipo de grão. Para os acessos melhorados considerou-se principalmente o tipo de grão e a instituição responsável pela realização do melhoramento do acesso. Verificou-se a necessidade de se realizar a caracterização e avaliação de muitos acessos introduzidos e melhorados. Foi possível observar a existência de variabilidade genética entre os acessos introduzidos e melhorados. As características altura de planta e peso de mil grãos foram as que mais contribuíram para a discriminação dos genótipos. A utilização combinada do método de Tocher tendo como medida de dissimilaridade a distância euclidiana invertida e a análise de dispersão gráfica com base nos três primeiros componentes principais foi eficiente. Foi possível a amostragem de acessos para comporem uma coleção núcleo de milho com base em análise multivariada a partir de dados de caracterização e avaliação.Aiming at the selection of accessions to compose a core collection of maize, were sampled access introduced and improved of Active Germplasm Bank at Embrapa Milho e Sorgo, located in Sete Lagoas, MG, Brazil. The sampling strategy was based in multivariate analysis, and adopted a sampling rate of 20% of accesses. Stratification of introduced accessions was in according with the country of origin, place of assessment and type of grain. For improved access was considered mainly the type of grain and the institution responsible for improvement of access. There is a need to perform the

  10. Comparison of the behaviour of two core designs for ASTRID in case of severe accidents

    Energy Technology Data Exchange (ETDEWEB)

    Bertrand, F., E-mail: frederic.bertrand@cea.fr [CEA, DEN, DER, F-13108 Saint Paul-lez-Durance (France); Marie, N.; Prulhière, G.; Lecerf, J. [CEA, DEN, DER, F-13108 Saint Paul-lez-Durance (France); Seiler, J.M. [CEA, DEN, DTN, F-38054 Grenoble (France)

    2016-02-15

    Highlights: • Low void worth CFV and SFRv2 cores are compared for ASTRID pre-conceptual design. • Severe accident behaviour is assessed with a simplified calculation approach and tools. • Mitigation to limit reactivity inserted by core compaction is easier for CFV than for SFRv2 core. • When facing arbitrary reactivity ramps, CFV core would lead to lower energy release than SFRv2 core. • Time scale for core degradation is one order of magnitude larger for CFV than for SFRv2. - Abstract: The present paper is dedicated to the studies carried out during the first stage of the pre-conceptual design of the French demonstrator of fourth generation SFR reactors (ASTRID) in order to compare the behaviour of two envisaged core concepts under severe accident transients. Among the two studied core concepts, whose powers are 1500 MWth, the first one is a classical homogeneous core (called SFRv2) with large pin diameter whose the sodium overall voiding reactivity effect is 5 $. The second concept is an axially heterogeneous core (called CFV) whose global void reactivity effect is negative (−1.2 $ at the end of cycle at the equilibrium). The comparison of the cores relies on two typical accident families: a reactivity insertion (unprotected transient overpower, UTOP) and an overall loss of core cooling (unprotected loss of flow, ULOF). In the first part of the comparison, the primary phase of an UTOP is studied in order to assess typical features of the transient behaviour: power and reactivity evolutions, material heating and melting/vaporization and mechanical energy release due to fuel vapor expansion. The second part of the comparison deals with the calculation of the reactivity potential for degraded states (molten pools) representative of the secondary phase of a mild UTOP and of a strong UTOP (strong or mild qualifies the reactivity ramp inserted). According to the reactivity potential, the amount of fuel to extract from the core and the amount of absorber

  11. Optimal implantation depth and adherence to guidelines on permanent pacing to improve the results of transcatheter aortic valve replacement with the medtronic corevalve system: The CoreValve prospective, international, post-market ADVANCE-II study

    NARCIS (Netherlands)

    A.S. Petronio (Anna S.); J.-M. Sinning (Jan-Malte); N.M. van Mieghem (Nicolas); G. Zucchelli (Giulio); G. Nickenig (Georg); R. Bekeredjian (Raffi); B. Bosmans; F. Bedogni (Francesco); M. Branny (Marian); K. Stangl (Karl); J. Kovac (Jan); M. Schiltgen (Molly); S. Kraus (Stacia); P.P.T. de Jaegere (Peter)

    2015-01-01

    textabstractObjectives The aim of the CoreValve prospective, international, post-market ADVANCE-II study was to define the rates of conduction disturbances and permanent pacemaker implantation (PPI) after transcatheter aortic valve replacement with the Medtronic CoreValve System (Minneapolis, Minnes

  12. Optimal implantation depth and adherence to guidelines on permanent pacing to improve the results of transcatheter aortic valve replacement with the medtronic corevalve system: The CoreValve prospective, international, post-market ADVANCE-II study

    NARCIS (Netherlands)

    A.S. Petronio (Anna S.); J.-M. Sinning (Jan-Malte); N.M. van Mieghem (Nicolas); G. Zucchelli (Giulio); G. Nickenig (Georg); R. Bekeredjian (Raffi); B. Bosmans; F. Bedogni (Francesco); M. Branny (Marian); K. Stangl (Karl); J. Kovac (Jan); M. Schiltgen (Molly); S. Kraus (Stacia); P.P.T. de Jaegere (Peter)

    2015-01-01

    textabstractObjectives The aim of the CoreValve prospective, international, post-market ADVANCE-II study was to define the rates of conduction disturbances and permanent pacemaker implantation (PPI) after transcatheter aortic valve replacement with the Medtronic CoreValve System (Minneapolis, Minnes

  13. Facile synthesis of mercaptosuccinic acid-capped CdTe/CdS/ZnS core/double shell quantum dots with improved cell viability on different cancer cells and normal cells

    Science.gov (United States)

    Parani, Sundararajan; Bupesh, Giridharan; Manikandan, Elayaperumal; Pandian, Kannaiyan; Oluwafemi, Oluwatobi Samuel

    2016-11-01

    Water-soluble, mercaptosuccinic acid (MSA)-capped CdTe/CdS/ZnS core/double shell quantum dots (QDs) were prepared by successive growth of CdS and ZnS shells on the as-synthesized CdTe/CdSthin core/shell quantum dots. The formation of core/double shell structured QDs was investigated by ultraviolet-visible (UV-Vis) absorption and photoluminescence (PL) spectroscopy, PL decay studies, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The core/double shell QDs exhibited good photoluminescence quantum yield (PLQY) which is 70% higher than that of the parent core/shell QDs, and they are stable for months. The average particle size of the core/double shell QDs was ˜3 nm as calculated from the transmission electron microscope (TEM) images. The cytotoxicity of the QDs was evaluated on a variety of cancer cells such as HeLa, MCF-7, A549, and normal Vero cells by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) cell viability assay. The results showed that core/double shell QDs were less toxic to the cells when compared to the parent core/shell QDs. MCF-7 cells showed proliferation on incubation with QDs, and this is attributed to the metalloestrogenic activity of cadmium ions released from QDs. The core/double shell CdTe/CdS/ZnS (CSS) QDs were conjugated with transferrin and successfully employed for the biolabeling and fluorescent imaging of HeLa cells. These core/double shell QDs are highly promising fluorescent probe for cancer cell labeling and imaging applications.

  14. Development of core design technology for LMR

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Jin; Kim Young In; Kim, Young Il; Kim, Y. G.; Kim, S. J.; Song, H.; Kim, T. K.; Kim, W. S.; Hwang, W.; Lee, B. O.; Park, C. K.; Joo, H. K.; Yoo, J. W.; Kang, H. Y.; Park, W. S

    2000-05-01

    For the development of KALIMER (150 MWe) core conceptual design, design evolution and optimization for improved economics and safety enhancement was performed in the uranium metallic fueled equilibrium core design which uses U-Zr binary fuel not in excess of 20 percent enrichment. Utilizing results of the uranium ,metallic fueled core design, the breeder equilibrium core design with breeding ratio being over 1.1 was developed. In addition, utilizing LMR's excellent neutron economy, various core concepts for minor actinide burnup, inherent safety, economics and non-proliferation were realized and its optimization studies were performed. A code system for the LMR core conceptual design has been established through the implementation of needed functions into the existing codes and development of codes. To improve the accuracy of the core design, a multi-dimensional nodal transport code SOLTRAN, a three-dimensional transient code analysis code STEP, MATRA-LMR and ASSY-P for T/H analysis are under development. Through the automation of design calculations for efficient core design, an input generator and several interface codes have been developed. (author)

  15. Preliminary Safety Analysis of Anticipated Transient without Scram (ATWS) Events for the Prototype GEN-IV SFR (PGSFR) using MARS-LMR

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chiwoong; Ha, Kwiseok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    A safety analysis of ATWS for the recently designed Prototype GEN-IV Sodium Cooled Fast Reactor (PGSFR) was conducted. Unprotected Transient Over-Power (UTOP), Unprotected Loss OF Flow (ULOF), and Unprotected Loss Of Heat Sink (ULOHS) were selected as representative events for the ATWS. In an unprotected condition, the power in the core is only controlled by reactivity feedbacks, which are interacted with the thermal-hydraulic characteristics of the components in the plant. Heat is removed by the steam generator (SG) and decay heat removal system (DHRS). Therefore, the major objectives of the safety analysis of the ATWS events are to investigate the thermal hydraulic characteristics of the DHRS and the SG, the neutron kinetic characteristics of the reactivity feedback, and the interaction between the neutron kinetics, and the thermal-hydraulics during the events.

  16. Development of a novel carbon-coating strategy for producing core-shell structured carbon coated LiFePO4 for an improved Li-ion battery performance.

    Science.gov (United States)

    Pratheeksha, Parakandy Muzhikara; Mohan, Erabhoina Hari; Sarada, Bulusu Venkata; Ramakrishna, Mantripragada; Hembram, Kalyan; Srinivas, Pulakhandam Veera Venkata; Daniel, Paul Joseph; Rao, Tata Narasinga; Anandan, Srinivasan

    2016-12-21

    In the present study, LiFePO4 (LFP) has been synthesized using a flame spray pyrolysis unit followed by carbon coating on LFP using a novel strategy of dehydration assisted polymerization process (DAP) in order to improve its electronic conductivity. Characterization studies revealed the presence of a pure LFP structure and the formation of a thin, uniform and graphitic carbon layer with a thickness of 6-8 nm on the surface of the LFP. A carbon coated LFP with 3 wt% of carbon, using a DAP process, delivered a specific capacity of 167 mA h g(-1) at a 0.1C rate, whereas LFP carbon coated by a carbothermal process (CLFP-C) delivered a capacity of 145 mA h g(-1) at 0.1C. Further carbon coated LFP by the DAP exhibited a good rate capability and cyclic stability. The enhanced electrochemical performance of C-LFP by DAP is attributed to the presence of a uniform, thin and ordered graphitic carbon layer with a core-shell structure, which greatly increased the electronic conductivity of LFP and thereby showed an improved electro-chemical performance. Interestingly, the developed carbon coating process has been extended to synthesize a bulk quantity (0.5 kg) of carbon coated LFP under optimized experimental conditions as a part of up-scaling and the resulting material electro-chemical performance has been evaluated and compared with commercial electrode materials. Bulk C-LFP showed a capacity of 131 mA h g(-1) and 87 mA h g(-1) at a rate of 1C and at 10C, respectively, illustrating that the developed DAP process greatly improved the electrochemical performance of LFP in terms of rate capability and cyclic stability, not only during the lab scale synthesis but also during the large scale synthesis. Benchmark studies concluded that the electro-chemical performance of C-LFP by DAP is comparable with that of TODA LFP and better than that of UNTPL LFP. The DAP process developed in the present study can be extended to other electrode materials as well.

  17. The core paradox.

    Science.gov (United States)

    Kennedy, G. C.; Higgins, G. H.

    1973-01-01

    Rebuttal of suggestions from various critics attempting to provide an escape from the seeming paradox originated by Higgins and Kennedy's (1971) proposed possibility that the liquid in the outer core was thermally stably stratified and that this stratification might prove a powerful inhibitor to circulation of the outer core fluid of the kind postulated for the generation of the earth's magnetic field. These suggestions are examined and shown to provide no reasonable escape from the core paradox.

  18. K-core inflation

    OpenAIRE

    Alexander L. Wolman

    2011-01-01

    K-core inflation is a new class of underlying inflation measures. The two most popular measures of underlying inflation are core inflation and trimmed mean inflation. The former removes fixed categories of goods and services (food and energy) from the inflation calculation, and the latter removes fixed percentiles of the weighted distribution of price changes. In contrast, k-core inflation specifies a size of relative price change to be removed from the inflation calculation. Thus, the catego...

  19. Sediment Core Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Provides instrumentation and expertise for physical and geoacoustic characterization of marine sediments. DESCRIPTION: The multisensor core logger measures...

  20. Sediment Core Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Provides instrumentation and expertise for physical and geoacoustic characterization of marine sediments.DESCRIPTION: The multisensor core logger measures...

  1. Thermal and compositional stratification of the inner core

    CERN Document Server

    Labrosse, Stéphane

    2014-01-01

    The improvements on the knowledge of the seismic structure of the inner core and the complexities thereby revealed ask for a dynamical origin. Sub-solidus convection was one of the early suggestions to explain the seismic anisotropy but requires an unstable density gradient either from thermal or compositional origin, or both. Temperature and composition profiles in the inner core are computed using a unidimensional model of core evolution including diffusion in the inner core and fractional crystallization at the the inner core boundary (ICB). The thermal conductivity of the core has been recently revised upwardly and, moreover, found increasing with depth. Values of the heat flow across the core mantle boundary (CMB) sufficient to maintain convection in the whole outer core are not sufficient to make the temperature in the inner core super-isentropic and therefore prone to thermal instability. An unreasonably high CMB heat flow is necessary to this end. The compositional stratification results from a compet...

  2. Ice Core Investigations

    Science.gov (United States)

    Krim, Jessica; Brody, Michael

    2008-01-01

    What can glaciers tell us about volcanoes and atmospheric conditions? How does this information relate to our understanding of climate change? Ice Core Investigations is an original and innovative activity that explores these types of questions. It brings together popular science issues such as research, climate change, ice core drilling, and air…

  3. Making an Ice Core.

    Science.gov (United States)

    Kopaska-Merkel, David C.

    1995-01-01

    Explains an activity in which students construct a simulated ice core. Materials required include only a freezer, food coloring, a bottle, and water. This hands-on exercise demonstrates how a glacier is formed, how ice cores are studied, and the nature of precision and accuracy in measurement. Suitable for grades three through eight. (Author/PVD)

  4. Ice Core Investigations

    Science.gov (United States)

    Krim, Jessica; Brody, Michael

    2008-01-01

    What can glaciers tell us about volcanoes and atmospheric conditions? How does this information relate to our understanding of climate change? Ice Core Investigations is an original and innovative activity that explores these types of questions. It brings together popular science issues such as research, climate change, ice core drilling, and air…

  5. Iowa Core Annual Report

    Science.gov (United States)

    Iowa Department of Education, 2015

    2015-01-01

    One central component of a great school system is a clear set of expectations, or standards, that educators help all students reach. In Iowa, that effort is known as the Iowa Core. The Iowa Core represents the statewide academic standards, which describe what students should know and be able to do in math, science, English language arts, and…

  6. Mercury's core evolution

    Science.gov (United States)

    Deproost, Marie-Hélène; Rivoldini, Attilio; Van Hoolst, Tim

    2016-10-01

    Remote sensing data of Mercury's surface by MESSENGER indicate that Mercury formed under reducing conditions. As a consequence, silicon is likely the main light element in the core together with a possible small fraction of sulfur. Compared to sulfur, which does almost not partition into solid iron at Mercury's core conditions and strongly decreases the melting temperature, silicon partitions almost equally well between solid and liquid iron and is not very effective at reducing the melting temperature of iron. Silicon as the major light element constituent instead of sulfur therefore implies a significantly higher core liquidus temperature and a decrease in the vigor of compositional convection generated by the release of light elements upon inner core formation.Due to the immiscibility in liquid Fe-Si-S at low pressure (below 15 GPa), the core might also not be homogeneous and consist of an inner S-poor Fe-Si core below a thinner Si-poor Fe-S layer. Here, we study the consequences of a silicon-rich core and the effect of the blanketing Fe-S layer on the thermal evolution of Mercury's core and on the generation of a magnetic field.

  7. Extracting the Cores of Implicit Communities

    Institute of Scientific and Technical Information of China (English)

    YANG Nan; LIN Songxiang; GAO Qiang

    2007-01-01

    In this paper, we improve the trawling and point out some communities missed by trawling. We use the DBG (Dense Bipartite Graph) to identify a structure of a potential community instead of CBG (Complete Bipartite Graph). Based on DBG, we proposed a new method based on edge removal to extract cores from a web graph. Moreover, we improve the crawler to save only potential pages as fans of a core and save a lot of disk storage space. To evaluate the set of cores whether or not belong to a community, the statistics of term frequency is used. In the paper,the dataset of experiment were crawled under domain ".cn". The result show that the our algorithm works properly and some new cores can be found by our method.

  8. EEA core set of indicators. Guide

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This guide provides information on the quality of the 37 indicators in the EEA core set. Its primary role is to support improved implementation of the core set in the EEA, European topic centres and the European environment information and observation network (Eionet). In parallel, it is aimed at helping users outside the EEA/Eionet system make best use of the indicators in their own work. It is hoped that the guide will promote cooperation on improving indicator methodologies and data quality as part of the wider process to streamline and improve environmental reporting in the European Union and beyond. (au)

  9. Mars' core and magnetism.

    Science.gov (United States)

    Stevenson, D J

    2001-07-12

    The detection of strongly magnetized ancient crust on Mars is one of the most surprising outcomes of recent Mars exploration, and provides important insight about the history and nature of the martian core. The iron-rich core probably formed during the hot accretion of Mars approximately 4.5 billion years ago and subsequently cooled at a rate dictated by the overlying mantle. A core dynamo operated much like Earth's current dynamo, but was probably limited in duration to several hundred million years. The early demise of the dynamo could have arisen through a change in the cooling rate of the mantle, or even a switch in convective style that led to mantle heating. Presently, Mars probably has a liquid, conductive outer core and might have a solid inner core like Earth.

  10. CopperCore 2.2.3

    NARCIS (Netherlands)

    Vogten, Hubert; Martens, Harrie; Koper, Rob

    2005-01-01

    Changes in this version: great number of bug fixes with regard to notifcation handling, allowed empty items in order to be more compatible with Reload, added QTI content type for CopperCore Service Integration, improved error handling, improved Clicc and fixed a bug regarding the else operation in a

  11. CopperCore 2.2.3

    NARCIS (Netherlands)

    Vogten, Hubert; Martens, Harrie; Koper, Rob

    2005-01-01

    Changes in this version: great number of bug fixes with regard to notifcation handling, allowed empty items in order to be more compatible with Reload, added QTI content type for CopperCore Service Integration, improved error handling, improved Clicc and fixed a bug regarding the else operation in a

  12. Multi-core processors - An overview

    CERN Document Server

    Venu, Balaji

    2011-01-01

    Microprocessors have revolutionized the world we live in and continuous efforts are being made to manufacture not only faster chips but also smarter ones. A number of techniques such as data level parallelism, instruction level parallelism and hyper threading (Intel's HT) already exists which have dramatically improved the performance of microprocessor cores. This paper briefs on evolution of multi-core processors followed by introducing the technology and its advantages in today's world. The paper concludes by detailing on the challenges currently faced by multi-core processors and how the industry is trying to address these issues.

  13. The t-core of an s-core

    OpenAIRE

    Fayers, Matthew

    2010-01-01

    We consider the $t$-core of an $s$-core partition, when $s$ and $t$ are coprime positive integers. Olsson has shown that the $t$-core of an $s$-core is again an $s$-core, and we examine certain actions of the affine symmetric group on $s$-cores which preserve the $t$-core of an $s$-core. Along the way, we give a new proof of Olsson's result. We also give a new proof of a result of Vandehey, showing that there is a simultaneous $s$- and $t$-core which contains all others.

  14. The t-core of an s-core

    OpenAIRE

    Fayers, Matthew

    2010-01-01

    We consider the $t$-core of an $s$-core partition, when $s$ and $t$ are coprime positive integers. Olsson has shown that the $t$-core of an $s$-core is again an $s$-core, and we examine certain actions of the affine symmetric group on $s$-cores which preserve the $t$-core of an $s$-core. Along the way, we give a new proof of Olsson's result. We also give a new proof of a result of Vandehey, showing that there is a simultaneous $s$- and $t$-core which contains all others.

  15. Improved Performance of Dye-Sensitized Solar Cells Fabricated from a Coumarin NKX-2700 Dye-Sensitized TiO2/MgO Core-Shell Photoanode with an HfO2 Blocking Layer and a Quasi-Solid-State Electrolyte

    Science.gov (United States)

    Maheswari, D.; Venkatachalam, P.

    2015-03-01

    Dye sensitized solar cells (DSSC) were fabricated from a coumarin NKX-2700 dye-sensitized core-shell photoanode and a quasi-solid-state electrolyte, sandwiched together, with a cobalt sulfide-coated counter electrode. The core-shell photoanode consisted of a composite mixture of 90% TiO2 nanoparticles and 10% TiO2 nanowires (TNPW) as core layer and MgO nanoparticles (MNP) as shell layer. Hafnium oxide (HfO2) was applied to the core-shell photoanode film as a blocking layer. TiO2 nanoparticles, TiO2 nanowires, and TNPW/MNP were characterized by x-ray diffractometry, scanning electron microscopy, and transmission electron microscopy. It was apparent from the UV-visible spectrum of the sensitizing dye coumarin NKX-2700 that its absorption was maximum at 525 nm. Power conversion efficiency (PCE) was greater for DSSC-1, fabricated with a core-shell TNPW/MNP/HfO2 photoanode, than for the other DSSC; its photovoltaic properties were: short circuit photocurrent J sc = 19 mA/cm2, open circuit voltage ( V oc) = 720 mV, fill factor ( FF) = 66%, and PCE ( η) = 9.02%. The charge-transport and charge-recombination behavior of the DSSC were investigated by electrochemical impedance spectroscopy; the results showed that the composite core-shell film resulted in the lowest charge-transfer resistance ( R CE) and the longest electron lifetime ( τ eff). Hence, the improved performance of DSSC-1 could be ascribed to the core-shell photoanode with blocking layer, which increased electron transport and suppressed recombination of charge carriers at the photoanode/dye/electrolyte interface.

  16. Korrelasjon mellom core styrke, core stabilitet og utholdende styrke i core

    OpenAIRE

    Berg-Olsen, Andrea Marie; Fugelsøy, Eivor; Maurstad, Ann-Louise

    2010-01-01

    Formålet med studien var å se hvilke korrelasjon det er mellom core styrke, core stabilitet og utholdende styrke i core. Testingen bestod av tre hoveddeler hvor vi testet core styrke, core stabilitet og utholdende styrke i core. Innenfor core styrke og utholdende styrke i core ble tre ulike tester utført. Ved måling av core stabilitet ble det gjennomført kun en test. I core styrke ble isometrisk abdominal fleksjon, isometrisk rygg ekstensjon og isometrisk lateral fleksjon testet. Sit-ups p...

  17. Korrelasjon mellom core styrke, core stabilitet og utholdende styrke i core

    OpenAIRE

    Berg-Olsen, Andrea Marie; Fugelsøy, Eivor; Maurstad, Ann-Louise

    2010-01-01

    Formålet med studien var å se hvilke korrelasjon det er mellom core styrke, core stabilitet og utholdende styrke i core. Testingen bestod av tre hoveddeler hvor vi testet core styrke, core stabilitet og utholdende styrke i core. Innenfor core styrke og utholdende styrke i core ble tre ulike tester utført. Ved måling av core stabilitet ble det gjennomført kun en test. I core styrke ble isometrisk abdominal fleksjon, isometrisk rygg ekstensjon og isometrisk lateral fleksjon testet. Sit-ups p...

  18. Earth's inner core: Innermost inner core or hemispherical variations?

    NARCIS (Netherlands)

    Lythgoe, K. H.; Deuss, A.; Rudge, J. F.; Neufeld, J. A.

    2014-01-01

    The structure of Earth's deep inner core has important implications for core evolution, since it is thought to be related to the early stages of core formation. Previous studies have suggested that there exists an innermost inner core with distinct anisotropy relative to the rest of the inner core.

  19. Earth's inner core: Innermost inner core or hemispherical variations?

    NARCIS (Netherlands)

    Lythgoe, K. H.; Deuss, A.; Rudge, J. F.; Neufeld, J. A.

    2014-01-01

    The structure of Earth's deep inner core has important implications for core evolution, since it is thought to be related to the early stages of core formation. Previous studies have suggested that there exists an innermost inner core with distinct anisotropy relative to the rest of the inner core.

  20. The Rate of Core Collapse Supernovae to Redshift 2.5 From The CANDELS and CLASH Supernova Surveys

    CERN Document Server

    Strolger, Louis-Gregory; Rodney, Steven A; Graur, Or; Riess, Adam G; McCully, Curtis; Ravindranath, Swara; Mobasher, Bahram; Shahady, A Kristin

    2015-01-01

    The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) and Cluster Lensing And Supernova survey with Hubble (CLASH) multi-cycle treasury programs with the Hubble Space Telescope (HST) have provided new opportunities to probe the rate of core-collapse supernovae (CCSNe) at high redshift, now extending to $z\\approx2.5$. Here we use a sample of approximately 44 CCSNe to determine volumetric rates, $R_{CC}$, in six redshift bins in the range $0.195\\%$ confidence) with SFRs from IR luminous galaxies, or with SFR models that include simple evolution in the initial mass function over time. This scaling factor is expected if the fraction of the IMF contributing to CCSN progenitors is in the 8 to 50 $M_{\\odot}$ range. It is not supportive, however, of an upper mass limit for progenitors at $<20\\,M_{\\odot}$.

  1. IGCSE core mathematics

    CERN Document Server

    Wall, Terry

    2013-01-01

    Give your core level students the support and framework they require to get their best grades with this book dedicated to the core level content of the revised syllabus and written specifically to ensure a more appropriate pace. This title has been written for Core content of the revised Cambridge IGCSE Mathematics (0580) syllabus for first teaching from 2013. ? Gives students the practice they require to deepen their understanding through plenty of practice questions. ? Consolidates learning with unique digital resources on the CD, included free with every book. We are working with Cambridge

  2. Core shroud corner joints

    Science.gov (United States)

    Gilmore, Charles B.; Forsyth, David R.

    2013-09-10

    A core shroud is provided, which includes a number of planar members, a number of unitary corners, and a number of subassemblies each comprising a combination of the planar members and the unitary corners. Each unitary corner comprises a unitary extrusion including a first planar portion and a second planar portion disposed perpendicularly with respect to the first planar portion. At least one of the subassemblies comprises a plurality of the unitary corners disposed side-by-side in an alternating opposing relationship. A plurality of the subassemblies can be combined to form a quarter perimeter segment of the core shroud. Four quarter perimeter segments join together to form the core shroud.

  3. Core stability training on lower limb balance strength.

    Science.gov (United States)

    Dello Iacono, Antonio; Padulo, Johnny; Ayalon, Moshe

    2016-01-01

    This study aimed to assess the effects of core stability training on lower limbs' muscular asymmetries and imbalances in team sport. Twenty footballers were divided into two groups, either core stability or control group. Before each daily practice, core stability group (n = 10) performed a core stability training programme, while control group (n = 10) did a standard warm-up. The effects of the core stability training programme were assessed by performing isokinetic tests and single-leg countermovement jumps. Significant improvement was found for knee extensors peak torque at 3.14 rad · s(-1) (14%; P core stability group. The jump tests showed a significant reduction in the strength asymmetries in core stability group (-71.4%; P = 0.02) while a concurrent increase was seen in the control group (33.3%; P core exercises for optimal lower limbs strength balance development in young soccer players.

  4. Core Physics and Kinetics Calculations for the Fissioning Plasma Core Reactor

    Science.gov (United States)

    Butler, C.; Albright, D.

    2007-01-01

    Highly efficient, compact nuclear reactors would provide high specific impulse spacecraft propulsion. This analysis and numerical simulation effort has focused on the technical feasibility issues related to the nuclear design characteristics of a novel reactor design. The Fissioning Plasma Core Reactor (FPCR) is a shockwave-driven gaseous-core nuclear reactor, which uses Magneto Hydrodynamic effects to generate electric power to be used for propulsion. The nuclear design of the system depends on two major calculations: core physics calculations and kinetics calculations. Presently, core physics calculations have concentrated on the use of the MCNP4C code. However, initial results from other codes such as COMBINE/VENTURE and SCALE4a. are also shown. Several significant modifications were made to the ISR-developed QCALC1 kinetics analysis code. These modifications include testing the state of the core materials, an improvement to the calculation of the material properties of the core, the addition of an adiabatic core temperature model and improvement of the first order reactivity correction model. The accuracy of these modifications has been verified, and the accuracy of the point-core kinetics model used by the QCALC1 code has also been validated. Previously calculated kinetics results for the FPCR were described in the ISR report, "QCALC1: A code for FPCR Kinetics Model Feasibility Analysis" dated June 1, 2002.

  5. Biospecimen Core Resource - TCGA

    Science.gov (United States)

    The Cancer Genome Atlas (TCGA) Biospecimen Core Resource centralized laboratory reviews and processes blood and tissue samples and their associated data using optimized standard operating procedures for the entire TCGA Research Network.

  6. NICHD Zebrafish Core

    Data.gov (United States)

    Federal Laboratory Consortium — The core[HTML_REMOVED]s goal is to help researchers of any expertise perform zebrafish experiments aimed at illuminating basic biology and human disease mechanisms,...

  7. iPSC Core

    Data.gov (United States)

    Federal Laboratory Consortium — The induced Pluripotent Stem Cells (iPSC) Core was created in 2011 to accelerate stem cell research in the NHLBI by providing investigators consultation, technical...

  8. Reference: -300CORE [PLACE

    Lifescience Database Archive (English)

    Full Text Available -300CORE Forde BG, Heyworth A, Pywell J, Kreis M Nucleotide sequence of a B1 hordein gene and the identifica...tion of possible upstream regulatory elements in endosperm storage protein genes fr

  9. INTEGRAL core programme

    Science.gov (United States)

    Gehrels, N.; Schoenfelder, V.; Ubertini, P.; Winkler, C.

    1997-01-01

    The International Gamma Ray Astrophysics Laboratory (INTEGRAL) mission is described with emphasis on the INTEGRAL core program. The progress made in the planning activities for the core program is reported on. The INTEGRAL mission has a nominal lifetime of two years with a five year extension option. The observing time will be divided between the core program (between 30 and 35 percent during the first two years) and general observations. The core program consists of three main elements: the deep survey of the Galactic plane in the central radian of the Galaxy; frequent scans of the Galactic plane in the search for transient sources, and pointed observations of several selected sources. The allocation of the observation time is detailed and the sensitivities of the observations are outlined.

  10. Focusing on Core Business

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    China is regulating state-owned enterprises that are investing outside of their core business realms, concerned that poor investment decisions could lead to loss of state-owned assets, but some doubt the effect of the new regulation

  11. Organizing Core Tasks

    DEFF Research Database (Denmark)

    Boll, Karen

    Civil servants conduct the work which makes welfare states functions on an everyday bases: Police men police, school teachers teach, and tax inspectors inspect. Focus in this paper is on the core tasks of tax inspectors. The paper argues that their core task of securing the collection of revenue...... has remained much the same within the last 10 years. However, how the core task has been organized has changed considerable under the influence of various “organizing devices”. The paper focusses on how organizing devices such as risk assessment, output-focus, effect orientation, and treatment...... projects influence the organization of core tasks within the tax administration. The paper shows that the organizational transformations based on the use of these devices have had consequences both for the overall collection of revenue and for the employees’ feeling of “making a difference”. All in all...

  12. Core Elements of Outpatient Antibiotic Stewardship.

    Science.gov (United States)

    Sanchez, Guillermo V; Fleming-Dutra, Katherine E; Roberts, Rebecca M; Hicks, Lauri A

    2016-11-11

    The Core Elements of Outpatient Antibiotic Stewardship provides a framework for antibiotic stewardship for outpatient clinicians and facilities that routinely provide antibiotic treatment. This report augments existing guidance for other clinical settings. In 2014 and 2015, respectively, CDC released the Core Elements of Hospital Antibiotic Stewardship Programs and the Core Elements of Antibiotic Stewardship for Nursing Homes. Antibiotic stewardship is the effort to measure and improve how antibiotics are prescribed by clinicians and used by patients. Improving antibiotic prescribing involves implementing effective strategies to modify prescribing practices to align them with evidence-based recommendations for diagnosis and management. The four core elements of outpatient antibiotic stewardship are commitment, action for policy and practice, tracking and reporting, and education and expertise. Outpatient clinicians and facility leaders can commit to improving antibiotic prescribing and take action by implementing at least one policy or practice aimed at improving antibiotic prescribing practices. Clinicians and leaders of outpatient clinics and health care systems can track antibiotic prescribing practices and regularly report these data back to clinicians. Clinicians can provide educational resources to patients and families on appropriate antibiotic use. Finally, leaders of outpatient clinics and health systems can provide clinicians with education aimed at improving antibiotic prescribing and with access to persons with expertise in antibiotic stewardship. Establishing effective antibiotic stewardship interventions can protect patients and improve clinical outcomes in outpatient health care settings.

  13. Tuned Chamber Core Panel Acoustic Test Results

    Science.gov (United States)

    Schiller, Noah H.; Allen, Albert R.

    2016-01-01

    This report documents acoustic testing of tuned chamber core panels, which can be used to supplement the low-frequency performance of conventional acoustic treatment. The tuned chamber core concept incorporates low-frequency noise control directly within the primary structure and is applicable to sandwich constructions with a directional core, including corrugated-, truss-, and fluted-core designs. These types of sandwich structures have long, hollow channels (or chambers) in the core. By adding small holes through one of the facesheets, the hollow chambers can be utilized as an array of low-frequency acoustic resonators. These resonators can then be used to attenuate low-frequency noise (below 400 Hz) inside a vehicle compartment without increasing the weight or size of the structure. The results of this test program demonstrate that the tuned chamber core concept is effective when used in isolation or combined with acoustic foam treatments. Specifically, an array of acoustic resonators integrated within the core of the panels was shown to improve both the low-frequency absorption and transmission loss of the structure in targeted one-third octave bands.

  14. Improvement of magnetic hysteresis loss, corrosion resistance and compressive strength through spark plasma sintering magnetocaloric LaFe11.65Si1.35/Cu core-shell powders

    Directory of Open Access Journals (Sweden)

    Caiyin You

    2016-05-01

    Full Text Available LaFe11.65Si1.35/Cu core-shell powders were achieved by self-designed magnetron sputtering system, which presents a better solidification during spark plasma sintering in comparison to the naked LaFe11.65Si1.35 powders. Much higher compressive strength, lower corrosion current density and magnetic hysteresis losses are achieved for the sintered sample of LaFe11.65Si1.35/Cu core-shell powders without significant decrease of the magnetic entropy change. The compressive strength, corrosion current density and maximum magnetic hysteresis losses are 105.6 MPa/16.8 MPa, 1.08 × 10−3A/cm2/3.03 × 10−3 A/cm2 and 1.33 J/kg/2.71 J/kg, respectively for the sintered samples of core-shell structured/naked powders. The technique of fabricating the core-shell structured powders demonstrated here is also applicable for other types of functional powders.

  15. SG06, a fully continuous and varved sediment core from Lake Suigetsu, Japan: stratigraphy and potential for improving the radiocarbon calibration model and understanding of late Quaternary climate changes

    Science.gov (United States)

    Nakagawa, Takeshi; Gotanda, Katsuya; Haraguchi, Tsuyoshi; Danhara, Toru; Yonenobu, Hitoshi; Brauer, Achim; Yokoyama, Yusuke; Tada, Ryuji; Takemura, Keiji; Staff, Richard A.; Payne, Rebecca; Bronk Ramsey, Christopher; Bryant, Charlotte; Brock, Fiona; Schlolaut, Gordon; Marshall, Michael; Tarasov, Pavel; Lamb, Henry; Suigetsu 2006 Project Members

    2012-03-01

    The high potential of the varved sediments of Lake Suigetsu, central Japan, to provide a purely terrestrial radiocarbon calibration model and a chronology of palaeoclimatic changes has been widely recognised for the last two decades. However, this potential has not been fully realised since the only available long sediment core from the lake ('SG93') was extracted from a single bore hole and was therefore interrupted by gaps of unknown duration between successive core sections. In the summer of 2006, a new sediment core ('SG06') was recovered from the lake. Four separate boreholes were drilled and the parallel sets of cores recovered were found to overlap completely, without gaps between segments. This new record provides the ability to test existing atmospheric radiocarbon calibration models, as well as to assess the scale of inter-regional leads and lags in palaeoclimatic changes over the last Glacial-Interglacial cycle. Multi-disciplinary analyses from SG06 are still ongoing, but a reliable description of the sedimentary sequence needs to be provided to the wider science community before major outputs from the project are released, thereby allowing fully-informed critical evaluation of all subsequent releases of data based on the SG06 record. In this paper, we report key litho-stratigraphic information concerning the SG06 sediment core, highlighting changes in the clarity of annual laminations (varves) with depth, and possible implications for the mechanism of the climate change. We also discuss the potential of the SG06 record to meet the fundamental goals of the INQUA-INTIMATE project.

  16. Core graduate courses: A missed learning opportunity?

    Science.gov (United States)

    Singh, Chandralekha; Maries, Alexandru

    2013-01-01

    An important goal of graduate physics core courses is to help students develop expertise in problem solving and improve their reasoning and meta-cognitive skills. We explore the conceptual difficulties of physics graduate students by administering conceptual problems on topics covered in undergraduate physics courses before and after instruction in related first year core graduate courses. Here, we focus on physics graduate students' difficulties manifested by their performance on two qualitative problems involving diagrammatic representation of vector fields. Some graduate students had great difficulty in recognizing whether the diagrams of the vector fields had divergence and/or curl but they had no difficulty computing the divergence and curl of the vector fields mathematically. We also conducted individual discussions with various faculty members who regularly teach first year graduate physics core courses about the goals of these courses and the performance of graduate students on the conceptual problems after related instruction in core courses.

  17. Glass-clad semiconductor core optical fibers

    Science.gov (United States)

    Morris, Stephanie Lynn

    Glass-clad optical fibers comprising a crystalline semiconductor core have garnered considerable recent attention for their potential utility as novel waveguides for applications in nonlinear optics, sensing, power delivery, and biomedicine. As research into these fibers has progressed, it has become evident that excessive losses are limiting performance and so greater understanding of the underlying materials science, coupled with advances in fiber processing, is needed. More specifically, the semiconductor core fibers possess three performance-limiting characteristics that need to be addressed: (a) thermal expansion mismatches between crystalline core and glass cladding that lead to cracks, (b) the precipitation of oxide species in the core upon fiber cooling, which results from partial dissolution of the cladding glass by the core melt, and (c) polycrystallinity; all of which lead to scattering and increased transmission losses. This dissertation systematically studies each of these effects and develops both a fundamental scientific understanding of and practical engineering methods for reducing their impact. With respect to the thermal expansion mismatch and, in part, the dissolution of oxides, for the first time to our knowledge, oxide and non-oxide glass compositions are developed for a series of semiconductor cores based on two main design criteria: (1) matching the thermal expansion coefficient between semiconductor core and glass cladding to minimize cracking and (2) matching the viscosity-temperature dependences, such that the cladding glass draws into fiber at a temperature slightly above the melting point of the semiconductor in order to minimize dissolution and improve the fiber draw process. The x[Na 2O:Al2O3] + (100 - 2x)SiO2 glass compositional family was selected due to the ability to tailor the glass properties to match the aforementioned targets through slight variations in composition and adjusting the ratios of bridging and non-bridging oxygen

  18. Packing in protein cores

    Science.gov (United States)

    Gaines, J. C.; Clark, A. H.; Regan, L.; O'Hern, C. S.

    2017-07-01

    Proteins are biological polymers that underlie all cellular functions. The first high-resolution protein structures were determined by x-ray crystallography in the 1960s. Since then, there has been continued interest in understanding and predicting protein structure and stability. It is well-established that a large contribution to protein stability originates from the sequestration from solvent of hydrophobic residues in the protein core. How are such hydrophobic residues arranged in the core; how can one best model the packing of these residues, and are residues loosely packed with multiple allowed side chain conformations or densely packed with a single allowed side chain conformation? Here we show that to properly model the packing of residues in protein cores it is essential that amino acids are represented by appropriately calibrated atom sizes, and that hydrogen atoms are explicitly included. We show that protein cores possess a packing fraction of φ ≈ 0.56 , which is significantly less than the typically quoted value of 0.74 obtained using the extended atom representation. We also compare the results for the packing of amino acids in protein cores to results obtained for jammed packings from discrete element simulations of spheres, elongated particles, and composite particles with bumpy surfaces. We show that amino acids in protein cores pack as densely as disordered jammed packings of particles with similar values for the aspect ratio and bumpiness as found for amino acids. Knowing the structural properties of protein cores is of both fundamental and practical importance. Practically, it enables the assessment of changes in the structure and stability of proteins arising from amino acid mutations (such as those identified as a result of the massive human genome sequencing efforts) and the design of new folded, stable proteins and protein-protein interactions with tunable specificity and affinity.

  19. Inner core structure behind the PKP core phase triplication

    NARCIS (Netherlands)

    Blom, Nienke A.; Deuss, Arwen; Paulssen, Hanneke; Waszek, Lauren

    2015-01-01

    The structure of the Earth's inner core is not well known between depths of ∼100–200 km beneath the inner core boundary. This is a result of the PKP core phase triplication and the existence of strong precursors to PKP phases, which hinder the measurement of inner core compressional PKIKP waves at e

  20. Inner core structure behind the PKP core phase triplication

    NARCIS (Netherlands)

    Blom, Nienke A.; Deuss, Arwen; Paulssen, Hanneke; Waszek, Lauren

    The structure of the Earth's inner core is not well known between depths of ∼100–200 km beneath the inner core boundary. This is a result of the PKP core phase triplication and the existence of strong precursors to PKP phases, which hinder the measurement of inner core compressional PKIKP waves at

  1. Pressure Core Characterization

    Science.gov (United States)

    Santamarina, J. C.

    2014-12-01

    Natural gas hydrates form under high fluid pressure and low temperature, and are found in permafrost, deep lakes or ocean sediments. Hydrate dissociation by depressurization and/or heating is accompanied by a multifold hydrate volume expansion and host sediments with low permeability experience massive destructuration. Proper characterization requires coring, recovery, manipulation and testing under P-T conditions within the stability field. Pressure core technology allows for the reliable characterization of hydrate bearing sediments within the stability field in order to address scientific and engineering needs, including the measurement of parameters used in hydro-thermo-mechanical analyses, and the monitoring of hydrate dissociation under controlled pressure, temperature, effective stress and chemical conditions. Inherent sampling effects remain and need to be addressed in test protocols and data interpretation. Pressure core technology has been deployed to study hydrate bearing sediments at several locations around the world. In addition to pressure core testing, a comprehensive characterization program should include sediment analysis, testing of reconstituted specimens (with and without synthetic hydrate), and in situ testing. Pressure core characterization technology can be used to study other gas-charged formations such as deep sea sediments, coal bed methane and gas shales.

  2. Shape optimization of a Sodium Fast Reactor core

    Directory of Open Access Journals (Sweden)

    Dombre Emmanuel

    2013-01-01

    Full Text Available We apply in this paper a geometrical shape optimization method for the design of the core of a SFR (Sodium-cooled Fast Reactor in order to minimize a thermal counter-reaction known as the sodium void effect. In this kind of reactors, by increasing the temperature, the core may become liable to a strong increase of reactivity, a key-parameter governing the chain-reaction at quasi-static states. We first use the one group energy diffusion model and give the generalization to the two groups energy equation. We then give some numerical results in the case of the one group energy equation. Note that the application of our method leads to some designs whose interfaces can be parametrized by very smooth curves which can stand very far from realistic designs. We don’t explain here the method that it would be possible to use for recovering an operational design but there exists several penalization methods (see [2] that could be employed to this end. On applique dans cet article une méthode d’optimisation géométrique dans le cadre de la conception d’un cœur de réacteur SFR (Sodium-cooled Fast Reactor, i.e. réacteur à neutron rapide refroidi au sodium dans le but de minimiser une contre réaction thermique connue sous le nom d’effet de vidange sodium. Lorsqu’une augmentation de température survient, ce type de réacteur peut être sujet à une forte augmentation de réactivité, un paramètre clé dans le contrôle de la réaction en chaîne en régime quasi-statique. On a recours à l’équation de diffusion à un groupe puis on donne la généralisation du modèle d’optimisation pour l’équation de la diffusion à deux groupes d’énergie. On présente ensuite quelques résultats numériques obtenus dans le cas de l’équation à un groupe d’énergie. On note que l’application de cette méthode conduit à des designs de cœur présentant des interfaces très régulières qui sont loin d’un design de cœur faisable sur le

  3. Assessing Core Competencies

    Science.gov (United States)

    Narayanan, M.

    2004-12-01

    Catherine Palomba and Trudy Banta offer the following definition of assessment, adapted from one provided by Marches in 1987. Assessment in the systematic collection, review, and use of information about educational programs undertaken for the purpose of improving student learning and development. (Palomba and Banta 1999). It is widely recognized that sophisticated computing technologies are becoming a key element in today's classroom instructional techniques. Regardless, the Professor must be held responsible for creating an instructional environment in which the technology actually supplements learning outcomes of the students. Almost all academic disciplines have found a niche for computer-based instruction in their respective professional domain. In many cases, it is viewed as an essential and integral part of the educational process. Educational institutions are committing substantial resources to the establishment of dedicated technology-based laboratories, so that they will be able to accommodate and fulfill students' desire to master certain of these specific skills. This type of technology-based instruction may raise some fundamental questions about the core competencies of the student learner. Some of the most important questions are : 1. Is the utilization of these fast high-powered computers and user-friendly software programs creating a totally non-challenging instructional environment for the student learner ? 2. Can technology itself all too easily overshadow the learning outcomes intended ? 3. Are the educational institutions simply training students how to use technology rather than educating them in the appropriate field ? 4. Are we still teaching content-driven courses and analysis oriented subject matter ? 5. Are these sophisticated modern era technologies contributing to a decline in the Critical Thinking Capabilities of the 21st century technology-savvy students ? The author tries to focus on technology as a tool and not on the technology

  4. Development of core design and analyses technology for integral reactor

    Energy Technology Data Exchange (ETDEWEB)

    Zee, Sung Quun; Lee, C. C.; Song, J. S. and others

    1999-03-01

    Integral reactors are developed for the applications such as sea water desalination, heat energy for various industries, and power sources for large container ships. In order to enhance the inherent and passive safety features, low power density concept is chosen for the integral reactor SMART. Moreover, ultra-longer cycle and boron-free operation concepts are reviewed for better plant economy and simple design of reactor system. Especially, boron-free operation concept brings about large difference in core configurations and reactivity controls from those of the existing large size commercial nuclear power plants and also causes many differences in the safety aspects. The ultimate objectives of this study include detailed core design of a integral reactor, development of the core design system and technology, and finally acquisition of the system design certificate. The goal of the first stage is the conceptual core design, that is, to establish the design bases and requirements suitable for the boron-free concept, to develop a core loading pattern, to analyze the nuclear, thermal and hydraulic characteristics of the core and to perform the core shielding design. Interface data for safety and performance analyses including fuel design data are produced for the relevant design analysis groups. Nuclear, thermal and hydraulic, shielding design and analysis code systems necessary for the core conceptual design are established through modification of the existing design tools and newly developed methodology and code modules. Core safety and performance can be improved by the technology development such as boron-free core optimization, advaned core monitoring and operational aid system. Feasiblity study on the improvement of the core protection and monitoring system will also contribute toward core safety and performance. Both the conceptual core design study and the related technology will provide concrete basis for the next design phase. This study will also

  5. 核心稳定性训练对发展普通高校大学生足球专项力量的试验研究%The Experimental Study on Improving College Students' Special Strength in Football Playing Through Core Stability Training

    Institute of Scientific and Technical Information of China (English)

    张熙; 周广利

    2012-01-01

    Aiming at football majors' core stability training,the paper studies the influence of special strength from core stability training through experiments.The results show that there are significant differences between the experiment group and the control group after 20 weeks' core stability training.This explains that core stability training has obvious effect on improving college students' special strength in football playing.%通过实验对普通高校自愿参加足球运动学生的进行核心稳定性训练对其专项力量的影响进行研究,发现通过二十周的核心稳定性训练,实验组与对照组在实验结果上出现了显著性差异,说明核心稳定性训练对提高普通高校大学生参与者足球专项力量有着明显的影响作用.

  6. 钻芯检测结构混凝土强度技术的改善与提高%Improvement and Increase of Core-drilling Structural Concrete Strength Detection Technique

    Institute of Scientific and Technical Information of China (English)

    邸小坛; 徐骋; 陶里; 周燕

    2001-01-01

    介绍结构混凝土强度的检测方法——钻芯法修正法及修正原理。在该方法中,利用误差理论中的置信度和估计精度理论,合理确定钻芯修正所需要的芯样数量。钻芯法修正法的实质是对混凝土强度检验结果的平均值的可信程度和检测精度提出具体的要求。%In this article, authors introduce a structural concrete strength detection method, core-drilling amendment method and amendment principles. This method properly determined the sample quantity to make core-drilling amendment with the confidence degree and precision estimate theory of error theory. The essential content of the core-drilling amendment method is to determine the requirement of confidence degree and detection precision degree of the average detection results of concrete strength.

  7. GREEN CORE HOUSE

    Directory of Open Access Journals (Sweden)

    NECULAI Oana

    2017-05-01

    Full Text Available The Green Core House is a construction concept with low environmental impact, having as main central element a greenhouse. The greenhouse has the innovative role to use the biomass energy provided by plants to save energy. Although it is the central piece, the greenhouse is not the most innovative part of the Green Core House, but the whole building ensemble because it integrates many other sustainable systems as "waste purification systems", "transparent photovoltaic panels" or "double skin façades".

  8. Birefringent hollow core fibers

    DEFF Research Database (Denmark)

    Roberts, John

    2007-01-01

    Hollow core photonic crystal fiber (HC-PCF), fabricated according to a nominally non-birefringent design, shows a degree of un-controlled birefringence or polarization mode dispersion far in excess of conventional non polarization maintaining fibers. This can degrade the output pulse in many...... and an increased overlap between the polarization modes at the glass interfaces. The interplay between these effects leads to a wavelength for optimum polarization maintenance, lambda(PM), which is detuned from the wavelength of highest birefringence. By a suitable fiber design involving antiresonance of the core...

  9. Birefringent hollow core fibers

    DEFF Research Database (Denmark)

    Roberts, John

    2007-01-01

    Hollow core photonic crystal fiber (HC-PCF), fabricated according to a nominally non-birefringent design, shows a degree of un-controlled birefringence or polarization mode dispersion far in excess of conventional non polarization maintaining fibers. This can degrade the output pulse in many...... and an increased overlap between the polarization modes at the glass interfaces. The interplay between these effects leads to a wavelength for optimum polarization maintenance, lambda(PM), which is detuned from the wavelength of highest birefringence. By a suitable fiber design involving antiresonance of the core...

  10. Application Service Providers (ASP) Adoption in Core and Non-Core Functions

    OpenAIRE

    Chan, Aman Y.M.; Vincent Cho

    2009-01-01

    With the further improvement in internet bandwidth, connection stability and data transmission security, a new wave of Application Service Providers (ASP) is on his way. The recent booming on some models such as Software Application as Service (SaaS) and On-Demand in 2008, has led to emergence of ASP model in core business functions. The traditional IS outsourcing covers the non-core business functions that are not critical to business performance and competitive advantages. Comparing with tr...

  11. Intracluster stars in the Virgo Cluster core

    NARCIS (Netherlands)

    Aguerri, JAL; Gerhard, OE; Arnaboldi, M; Napolitano, NR; Castro-Rodriguez, N; Freeman, KC

    2005-01-01

    We have investigated the properties of the diffuse light in the Virgo Cluster core region, based on the detection of intracluster planetary nebulae (PNs) in four fields. We eliminate the bias from misclassified faint continuum objects, using improved Monte Carlo simulations, and the contaminations b

  12. ACGME core competencies: where are we?

    Science.gov (United States)

    Yaszay, Burt; Kubiak, Erik; Agel, Julie; Hanel, Douglas P

    2009-03-01

    Beginning in July 2002, the Accreditation Council for Graduate Medical Education (ACGME) instructed all residency programs to require their residents to demonstrate competency in 6 core areas: patient care, interpersonal and communication skills, medical knowledge, professionalism, practice-based learning, and systems-based practice. The goal was to have objective markers of performance that would serve as a gauge to determine a program's accreditation. To determine the experiences of orthopedic residency programs with regard to the ACGME's core competencies, a national survey was administered to orthopedic program directors and selected orthopedic residents. Of those orthopedic programs that responded, most appeared to be complying with the ACGME requirements. Both directors and residents thought patient care and medical knowledge ranked most important, while practice-based learning and systems-based practice were assigned the lowest ranks. Barriers to implementation of the core competencies included low priority compared with clinical duties, lack of faculty or resident education, and lack of formal orthopedic core competencies. Residents and program directors agreed that their programs would benefit from a definition of each of the core competencies, including a greater commitment to the processes involved in surgical procedures. This study demonstrated a commitment to the core competencies by the programs that responded. The survey also suggested this commitment would be aided by improved definitions of some of the competencies for the orthopedic resident.

  13. Investigation of EAS cores

    Science.gov (United States)

    Shaulov, S. B.; Beyl, P. F.; Beysembaev, R. U.; Beysembaeva, E. A.; Bezshapov, S. P.; Borisov, A. S.; Cherdyntceva, K. V.; Chernyavsky, M. M.; Chubenko, A. P.; Dalkarov, O. D.; Denisova, V. G.; Erlykin, A. D.; Kabanova, N. V.; Kanevskaya, E. A.; Kotelnikov, K. A.; Morozov, A. E.; Mukhamedshin, R. A.; Nam, R. A.; Nesterova, N. M.; Nikolskaya, N. M.; Pavluchenko, V. P.; Piskal, V. V.; Puchkov, V. S.; Pyatovsky, S. E.; Ryabov, V. A.; Sadykov, T. Kh.; Schepetov, A. L.; Smirnova, M. D.; Stepanov, A. V.; Uryson, A. V.; Vavilov, Yu. N.; Vildanov, N. G.; Vildanova, L. I.; Zayarnaya, I. S.; Zhanceitova, J. K.; Zhukov, V. V.

    2017-06-01

    The development of nuclear-electromagnetic cascade models in air in the late forties have shown informational content of the study of cores of extensive air showers (EAS). These investigations were the main goal in different experiments which were carried out over many years by a variety of methods. Outcomes of such investigations obtained in the HADRON experiment using an X-ray emulsion chamber (XREC) as a core detector are considered. The Ne spectrum of EAS associated with γ-ray families, spectra of γ-rays (hadrons) in EAS cores and the Ne dependence of the muon number, ⟨Nμ⟩, in EAS with γ-ray families are obtained for the first time at energies of 1015-1017 eV with this method. A number of new effects were observed, namely, an abnormal scaling violation in hadron spectra which are fundamentally different from model predictions, an excess of muon number in EAS associated with γ-ray families, and the penetrating component in EAS cores. It is supposed that the abnormal behavior of γ-ray spectra and Ne dependence of the muon number are explained by the emergence of a penetrating component in the 1st PCR spectrum `knee' range. Nuclear and astrophysical explanations of the origin of the penetrating component are discussed. The necessity of considering the contribution of a single close cosmic-ray source to explain the PCR spectrum in the knee range is noted.

  14. Some Core Contested Concepts

    Science.gov (United States)

    Chomsky, Noam

    2015-01-01

    Core concepts of language are highly contested. In some cases this is legitimate: real empirical and conceptual issues arise. In other cases, it seems that controversies are based on misunderstanding. A number of crucial cases are reviewed, and an approach to language is outlined that appears to have strong conceptual and empirical motivation, and…

  15. Looking for Core Values

    Science.gov (United States)

    Carter, Margie

    2010-01-01

    People who view themselves as leaders, not just managers or teachers, are innovators who focus on clarifying core values and aligning all aspects of the organization with these values to grow their vision. A vision for an organization can't be just one person's idea. Visions grow by involving people in activities that help them name and create…

  16. Nucleosome Core Particle

    Science.gov (United States)

    1997-01-01

    Nucleosome Core Particle grown on STS-81. The fundamental structural unit of chromatin and is the basis for organization within the genome by compaction of DNA within the nucleus of the cell and by making selected regions of chromosomes available for transcription and replication. Principal Investigator's are Dr. Dan Carter and Dr. Gerard Bunick of New Century Pharmaceuticals.

  17. Investigation of EAS cores

    Directory of Open Access Journals (Sweden)

    Shaulov S.B.

    2017-01-01

    Full Text Available The development of nuclear-electromagnetic cascade models in air in the late forties have shown informational content of the study of cores of extensive air showers (EAS. These investigations were the main goal in different experiments which were carried out over many years by a variety of methods. Outcomes of such investigations obtained in the HADRON experiment using an X-ray emulsion chamber (XREC as a core detector are considered. The Ne spectrum of EAS associated with γ-ray families, spectra of γ-rays (hadrons in EAS cores and the Ne dependence of the muon number, ⟨Nμ⟩, in EAS with γ-ray families are obtained for the first time at energies of 1015–1017 eV with this method. A number of new effects were observed, namely, an abnormal scaling violation in hadron spectra which are fundamentally different from model predictions, an excess of muon number in EAS associated with γ-ray families, and the penetrating component in EAS cores. It is supposed that the abnormal behavior of γ-ray spectra and Ne dependence of the muon number are explained by the emergence of a penetrating component in the 1st PCR spectrum ‘knee’ range. Nuclear and astrophysical explanations of the origin of the penetrating component are discussed. The necessity of considering the contribution of a single close cosmic-ray source to explain the PCR spectrum in the knee range is noted.

  18. Modeling Core Collapse Supernovae

    Science.gov (United States)

    Mezzacappa, Anthony

    2017-01-01

    Core collapse supernovae, or the death throes of massive stars, are general relativistic, neutrino-magneto-hydrodynamic events. The core collapse supernova mechanism is still not in hand, though key components have been illuminated, and the potential for multiple mechanisms for different progenitors exists. Core collapse supernovae are the single most important source of elements in the Universe, and serve other critical roles in galactic chemical and thermal evolution, the birth of neutron stars, pulsars, and stellar mass black holes, the production of a subclass of gamma-ray bursts, and as potential cosmic laboratories for fundamental nuclear and particle physics. Given this, the so called ``supernova problem'' is one of the most important unsolved problems in astrophysics. It has been fifty years since the first numerical simulations of core collapse supernovae were performed. Progress in the past decade, and especially within the past five years, has been exponential, yet much work remains. Spherically symmetric simulations over nearly four decades laid the foundation for this progress. Two-dimensional modeling that assumes axial symmetry is maturing. And three-dimensional modeling, while in its infancy, has begun in earnest. I will present some of the recent work from the ``Oak Ridge'' group, and will discuss this work in the context of the broader work by other researchers in the field. I will then point to future requirements and challenges. Connections with other experimental, observational, and theoretical efforts will be discussed, as well.

  19. The Earth's Core.

    Science.gov (United States)

    Jeanloz, Raymond

    1983-01-01

    The nature of the earth's core is described. Indirect evidence (such as that determined from seismological data) indicates that it is an iron alloy, solid toward its center but otherwise liquid. Evidence also suggests that it is the turbulent flow of the liquid that generates the earth's magnetic field. (JN)

  20. Some Core Contested Concepts

    Science.gov (United States)

    Chomsky, Noam

    2015-01-01

    Core concepts of language are highly contested. In some cases this is legitimate: real empirical and conceptual issues arise. In other cases, it seems that controversies are based on misunderstanding. A number of crucial cases are reviewed, and an approach to language is outlined that appears to have strong conceptual and empirical motivation, and…

  1. Languages for Dublin Core.

    Science.gov (United States)

    Baker, Thomas

    1998-01-01

    Focusing on languages for the Dublin Core, examines the experience of some related ways to seek semantic interoperability through simplicity: planned languages, interlingua constructs, and pidgins. Also defines the conceptual and organizational problem of maintaining a metadata standard in multiple languages. (AEF)

  2. Core calculations of JMTR

    Energy Technology Data Exchange (ETDEWEB)

    Nagao, Yoshiharu [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    1998-03-01

    In material testing reactors like the JMTR (Japan Material Testing Reactor) of 50 MW in Japan Atomic Energy Research Institute, the neutron flux and neutron energy spectra of irradiated samples show complex distributions. It is necessary to assess the neutron flux and neutron energy spectra of an irradiation field by carrying out the nuclear calculation of the core for every operation cycle. In order to advance core calculation, in the JMTR, the application of MCNP to the assessment of core reactivity and neutron flux and spectra has been investigated. In this study, in order to reduce the time for calculation and variance, the comparison of the results of the calculations by the use of K code and fixed source and the use of Weight Window were investigated. As to the calculation method, the modeling of the total JMTR core, the conditions for calculation and the adopted variance reduction technique are explained. The results of calculation are shown. Significant difference was not observed in the results of neutron flux calculations according to the difference of the modeling of fuel region in the calculations by K code and fixed source. The method of assessing the results of neutron flux calculation is described. (K.I.)

  3. The core and cosmopolitans

    DEFF Research Database (Denmark)

    Dahlander, Linus; Frederiksen, Lars

    2012-01-01

    Users often interact and help each other solve problems in communities, but few scholars have explored how these relationships provide opportunities to innovate. We analyze the extent to which people positioned within the core of a community as well as people that are cosmopolitans positioned...

  4. Schumpeter's core works revisited

    DEFF Research Database (Denmark)

    Andersen, Esben Sloth

    2012-01-01

    This paper organises Schumpeter’s core books in three groups: the programmatic duology,the evolutionaryeconomic duology,and the socioeconomic synthesis. By analysing these groups and their interconnections from the viewpoint of modern evolutionaryeconomics,the paper summarises resolved problems...

  5. Adult educators' core competences

    DEFF Research Database (Denmark)

    Wahlgren, Bjarne

    2016-01-01

    environment as well as the kind of adult education concerned (e.g. basic education, work-related education etc.). However, it seems that it is possible to identify certain competence requirements which transcend national, cultural and functional boundaries. This research note summarises these common or “core...

  6. Adult educators' core competences

    DEFF Research Database (Denmark)

    Wahlgren, Bjarne

    2016-01-01

    environment as well as the kind of adult education concerned (e.g. basic education, work-related education etc.). However, it seems that it is possible to identify certain competence requirements which transcend national, cultural and functional boundaries. This research note summarises these common or “core...

  7. Discussion on improving cast-in-place concrete ribbed beam hollow floor with GBF honeycomb core construction technology%提高 GBF 蜂巢芯现浇混凝土密肋梁空心楼盖施工技术的探讨

    Institute of Scientific and Technical Information of China (English)

    张世明

    2015-01-01

    GBF蜂巢芯现浇混凝土密肋梁空心楼盖是一种新型的楼盖结构。本文从一个工程实例出发,介绍了蜂巢芯安装及相应的技术措施,详细介绍了提高其施工质量的模板、钢筋、混凝土技术措施。%Cast-in-place concrete ribbed beams hollow floor with GBF honeycomb core is a new type of floor structure.Based on an en-gineering example, this paper introduces the installation of honeycomb core and corresponding technical measures ,and the template, steel bar and concrete technical measures was introduced in detail to improve the quality of its construction.

  8. Comparison of HCV core and coreE1E2 virus-like particles generated by stably transfected Leishmania tarentolae for stimulation of Th1 immune responses in mice.

    Science.gov (United States)

    Bolhassani, Azam; Davoudi, Noushin; Agi, Elnaz; Motevalli, Fatemeh

    2017-01-25

    Virus-like particles (VLPs) could be improved into successful immunogens as well as a potent delivery vehicle, but however, the current expression systems for VLPs production have some limitations. Recently, we developed a novel strategy to produce two HCV VLPs containing core or coreE1E2 proteins using stably transfected Leishmania tarentolae promastigotes. Then, BALB/c mice were injected by both viral like particles in different immunization strategies such as homologous DNA-, homologous VLP-, and heterologous DNA/ VLP-based immunizations. TEM microscopy indicated HCV core and HCV coreE1E2 VLP assembly with average size of 30-40 and 40-60 nm after purification, respectively. Our results showed that homologous immunizations with both HCV core or coreE1E2 VLPs significantly induced anti-core or anti-coreE1E2 antibody responses, respectively as well as secretion of IFN-γ cytokine as compared to other strategies. Moreover, DNA-prime/VLP-boost regimens significantly elicited higher levels of IFN-γ and antibody responses in comparison with homologous DNA/DNA regimens. The groups immunized with homologous or heterologous coreE1E2 VLPs showed markedly higher immune responses as compared to groups immunized with core VLP regimens against coreE1E2 protein. The crude HCV VLPs generated by Leishmania expression system could elicit a Th1-type response as a promising vaccine candidate against HCV infections.

  9. MOX燃料堆芯热工特性及设计限值研究%Analysis of MOX core thermal characteristics and design criteria

    Institute of Scientific and Technical Information of China (English)

    刘一哲; 喻宏; 田和春

    2009-01-01

    For the MOX core of a Sodium-cooled Fast Reactor(SFR) nuclear power plant, the advantages are higher linear power, burn-up and outlet temperature. Core thermal hydraulic design meets some new issues. Based on the analysis of MOX fuel characteristics, the thermal design criteria of core were raised in this paper. Core thermal characteristics and margin were analyzed for the 870 MWe nuclear power plant. The results showed that higher thermal parameters were reasonable and feasible for the MOX core, and the thermal margin satisfied the requirements.%使用MOX燃料的快堆核电站以其线功率高、燃耗高、堆芯出口温度高等特点,对堆芯热工设计提出了新的问题.本文在对MOX燃料热工性能分析的基础上,给出了主要的热工设计限值,并以电功率870 MW电站为参考,初步分析了其堆芯热工特性和设计裕量.结果表明对于MOX燃料,较高的堆芯热工参数合理可行,且具有足够的裕量.

  10. Application of Core Dynamics Modeling to Core-Mantle Interactions

    Science.gov (United States)

    Kuang, Weijia

    2003-01-01

    Observations have demonstrated that length of day (LOD) variation on decadal time scales results from exchange of axial angular momentum between the solid mantle and the core. There are in general four core-mantle interaction mechanisms that couple the core and the mantle. Of which, three have been suggested likely the dominant coupling mechanism for the decadal core-mantle angular momentum exchange, namely, gravitational core-mantle coupling arising from density anomalies in the mantle and in the core (including the inner core), the electromagnetic coupling arising from Lorentz force in the electrically conducting lower mantle (e.g. D-layer), and the topographic coupling arising from non-hydrostatic pressure acting on the core-mantle boundary (CMB) topography. In the past decades, most effort has been on estimating the coupling torques from surface geomagnetic observations (kinematic approach), which has provided insights on the core dynamical processes. In the meantime, it also creates questions and concerns on approximations in the studies that may invalidate the corresponding conclusions. The most serious problem is perhaps the approximations that are inconsistent with dynamical processes in the core, such as inconsistencies between the core surface flow beneath the CMB and the CMB topography, and that between the D-layer electric conductivity and the approximations on toroidal field at the CMB. These inconsistencies can only be addressed with numerical core dynamics modeling. In the past few years, we applied our MoSST (Modular, Scalable, Self-consistent and Three-dimensional) core dynamics model to study core-mantle interactions together with geodynamo simulation, aiming at assessing the effect of the dynamical inconsistencies in the kinematic studies on core-mantle coupling torques. We focus on topographic and electromagnetic core-mantle couplings and find that, for the topographic coupling, the consistency between the core flow and the CMB topography is

  11. Assessment of SFR Wire Wrap Simulation Uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Delchini, Marc-Olivier G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Reactor and Nuclear Systems Division; Popov, Emilian L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Reactor and Nuclear Systems Division; Pointer, William David [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Reactor and Nuclear Systems Division; Swiler, Laura P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-09-30

    Predictive modeling and simulation of nuclear reactor performance and fuel are challenging due to the large number of coupled physical phenomena that must be addressed. Models that will be used for design or operational decisions must be analyzed for uncertainty to ascertain impacts to safety or performance. Rigorous, structured uncertainty analyses are performed by characterizing the model’s input uncertainties and then propagating the uncertainties through the model to estimate output uncertainty. This project is part of the ongoing effort to assess modeling uncertainty in Nek5000 simulations of flow configurations relevant to the advanced reactor applications of the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program. Three geometries are under investigation in these preliminary assessments: a 3-D pipe, a 3-D 7-pin bundle, and a single pin from the Thermal-Hydraulic Out-of-Reactor Safety (THORS) facility. Initial efforts have focused on gaining an understanding of Nek5000 modeling options and integrating Nek5000 with Dakota. These tasks are being accomplished by demonstrating the use of Dakota to assess parametric uncertainties in a simple pipe flow problem. This problem is used to optimize performance of the uncertainty quantification strategy and to estimate computational requirements for assessments of complex geometries. A sensitivity analysis to three turbulent models was conducted for a turbulent flow in a single wire wrapped pin (THOR) geometry. Section 2 briefly describes the software tools used in this study and provides appropriate references. Section 3 presents the coupling interface between Dakota and a computational fluid dynamic (CFD) code (Nek5000 or STARCCM+), with details on the workflow, the scripts used for setting up the run, and the scripts used for post-processing the output files. In Section 4, the meshing methods used to generate the THORS and 7-pin bundle meshes are explained. Sections 5, 6 and 7 present numerical results for the 3-D pipe, the single pin THORS mesh, and the 7-pin bundle mesh, respectively.

  12. Efficiency of static core turn-off in a system-on-a-chip with variation

    Science.gov (United States)

    Cher, Chen-Yong; Coteus, Paul W; Gara, Alan; Kursun, Eren; Paulsen, David P; Schuelke, Brian A; Sheets, II, John E; Tian, Shurong

    2013-10-29

    A processor-implemented method for improving efficiency of a static core turn-off in a multi-core processor with variation, the method comprising: conducting via a simulation a turn-off analysis of the multi-core processor at the multi-core processor's design stage, wherein the turn-off analysis of the multi-core processor at the multi-core processor's design stage includes a first output corresponding to a first multi-core processor core to turn off; conducting a turn-off analysis of the multi-core processor at the multi-core processor's testing stage, wherein the turn-off analysis of the multi-core processor at the multi-core processor's testing stage includes a second output corresponding to a second multi-core processor core to turn off; comparing the first output and the second output to determine if the first output is referring to the same core to turn off as the second output; outputting a third output corresponding to the first multi-core processor core if the first output and the second output are both referring to the same core to turn off.

  13. ABSTRACTS Preliminary Study of Strategic Inner Cores

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    When a strategic entity attempts to make a dicision, first the project must be m accoroance wlm its strategic framework as well as make the strategic inner cores prominent. The existing theories of development strategy indicate that the formation of the framework can be divided into the following parts: inside and outside environments, purpose, goal, key points, and countermeasures. The strategic inner cores that put forward by this paper is the intensification and advancement for the theory of strategic framework, strategic orientation, strategic vision and main line are inciuded. Appearance of these ideas have improved the theory and enhanced strategic practice.

  14. How Should the Graduate Economics Core Be Changed?

    Science.gov (United States)

    Abito, Jose Miguel; Borovickova, Katarina; Golden, Hays; Goldin, Jacob; Masten, Matthew A.; Morin, Miguel; Poirier, Alexandre; Pons, Vincent; Romem, Israel; Williams, Tyler; Yoon, Chamna

    2011-01-01

    The authors present suggestions by graduate students from a range of economics departments for improving the first-year core sequence in economics. The students identified a number of elements that should be added to the core: more training in building microeconomic models, a discussion of the methodological foundations of model-building, more…

  15. Neutron spectrometric methods for core inventory verification in research reactors

    CERN Document Server

    Ellinger, A; Hansen, W; Knorr, J; Schneider, R

    2002-01-01

    In consequence of the Non-Proliferation Treaty safeguards, inspections are periodically made in nuclear facilities by the IAEA and the EURATOM Safeguards Directorate. The inspection methods are permanently improved. Therefore, the Core Inventory Verification method is being developed as an indirect method for the verification of the core inventory and to check the declared operation of research reactors.

  16. Dispersion behavior of core-shell silica-polymer nanoparticles

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Core-shell silica nanoparticles are superior in modifying surface wetting behavior, enhancing nucleation and growth in crystallization, improving dispersion of naked nanoparticles, and thus upgrading the overall properties of organic polymers. The dispersion behavior and morphology of monodisperse core-shell silica particles in several polymers including polyesters are reviewed and their potential applications are discussed.

  17. USGS Core Research Center (CRC) Collection of Core

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Core Research Center (CRC) was established in 1974 by the U.S. Geological Survey (USGS) to preserve valuable rock cores for use by scientists and educators from...

  18. Ice Cores of the National Ice Core Laboratory

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The U.S. National Ice Core Laboratory (NICL) is a facility for storing, curating, and studying ice cores recovered from the polar regions of the world. It provides...

  19. Core Outlet Temperature Study

    Energy Technology Data Exchange (ETDEWEB)

    Moisseytsev, A. [Argonne National Laboratory (ANL), Argonne, IL (United States); Hoffman, E. [Argonne National Laboratory (ANL), Argonne, IL (United States); Majumdar, S. [Argonne National Laboratory (ANL), Argonne, IL (United States)

    2008-07-28

    It is a known fact that the power conversion plant efficiency increases with elevation of the heat addition temperature. The higher efficiency means better utilization of the available resources such that higher output in terms of electricity production can be achieved for the same size and power of the reactor core or, alternatively, a lower power core could be used to produce the same electrical output. Since any nuclear power plant, such as the Advanced Burner Reactor, is ultimately built to produce electricity, a higher electrical output is always desirable. However, the benefits of the higher efficiency and electricity production usually come at a price. Both the benefits and the disadvantages of higher reactor outlet temperatures are analyzed in this work.

  20. Geomagnetism of earth's core

    Science.gov (United States)

    Benton, E. R.

    1983-01-01

    Instrumentation, analytical methods, and research goals for understanding the behavior and source of geophysical magnetism are reviewed. Magsat, launched in 1979, collected global magnetometer data and identified the main terrestrial magnetic fields. The data has been treated by representing the curl-free field in terms of a scalar potential which is decomposed into a truncated series of spherical harmonics. Solutions to the Laplace equation then extend the field upward or downward from the measurement level through intervening spaces with no source. Further research is necessary on the interaction between harmonics of various spatial scales. Attempts are also being made to analytically model the main field and its secular variation at the core-mantle boundary. Work is also being done on characterizing the core structure, composition, thermodynamics, energetics, and formation, as well as designing a new Magsat or a tethered satellite to be flown on the Shuttle.

  1. Geomagnetism of earth's core

    Science.gov (United States)

    Benton, E. R.

    1983-01-01

    Instrumentation, analytical methods, and research goals for understanding the behavior and source of geophysical magnetism are reviewed. Magsat, launched in 1979, collected global magnetometer data and identified the main terrestrial magnetic fields. The data has been treated by representing the curl-free field in terms of a scalar potential which is decomposed into a truncated series of spherical harmonics. Solutions to the Laplace equation then extend the field upward or downward from the measurement level through intervening spaces with no source. Further research is necessary on the interaction between harmonics of various spatial scales. Attempts are also being made to analytically model the main field and its secular variation at the core-mantle boundary. Work is also being done on characterizing the core structure, composition, thermodynamics, energetics, and formation, as well as designing a new Magsat or a tethered satellite to be flown on the Shuttle.

  2. Dynamics of core accretion

    Science.gov (United States)

    Nelson, Andrew F.; Ruffert, Maximilian

    2013-02-01

    We perform three-dimensional hydrodynamic simulations of gas flowing around a planetary core of mass Mpl = 10M⊕ embedded in a near Keplerian background flow, using a modified shearing box approximation. We assume an ideal gas behaviour following an equation of state with a fixed ratio of the specific heats, γ = 1.42, consistent with the conditions of a moderate-temperature background disc with solar composition. No radiative heating or cooling is included in the models. We employ a nested grid hydrodynamic code implementing the `Piecewise Parabolic Method' with as many as six fixed nested grids, providing spatial resolution on the finest grid comparable to the present-day diameters of Neptune and Uranus. We find that a strongly dynamically active flow develops such that no static envelope can form. The activity is not sensitive to plausible variations in the rotation curve of the underlying disc. It is sensitive to the thermodynamic treatment of the gas, as modelled by prescribed equations of state (either `locally isothermal' or `locally isentropic') and the temperature of the background disc material. The activity is also sensitive to the shape and depth of the core's gravitational potential, through its mass and gravitational softening coefficient. Each of these factors influences the magnitude and character of hydrodynamic feedback of the small-scale flow on the background, and we conclude that accurate modelling of such feedback is critical to a complete understanding of the core accretion process. The varying flow pattern gives rise to large, irregular eruptions of matter from the region around the core which return matter to the background flow: mass in the envelope at one time may not be found in the envelope at any later time. No net mass accretion into the envelope is observed over the course of the simulation and none is expected, due to our neglect of cooling. Except in cases of very rapid cooling however, as defined by locally isothermal or

  3. Some core contested concepts.

    Science.gov (United States)

    Chomsky, Noam

    2015-02-01

    Core concepts of language are highly contested. In some cases this is legitimate: real empirical and conceptual issues arise. In other cases, it seems that controversies are based on misunderstanding. A number of crucial cases are reviewed, and an approach to language is outlined that appears to have strong conceptual and empirical motivation, and to lead to conclusions about a number of significant issues that differ from some conventional beliefs.

  4. Central core disease

    Directory of Open Access Journals (Sweden)

    Jungbluth Heinz

    2007-05-01

    Full Text Available Abstract Central core disease (CCD is an inherited neuromuscular disorder characterised by central cores on muscle biopsy and clinical features of a congenital myopathy. Prevalence is unknown but the condition is probably more common than other congenital myopathies. CCD typically presents in infancy with hypotonia and motor developmental delay and is characterized by predominantly proximal weakness pronounced in the hip girdle; orthopaedic complications are common and malignant hyperthermia susceptibility (MHS is a frequent complication. CCD and MHS are allelic conditions both due to (predominantly dominant mutations in the skeletal muscle ryanodine receptor (RYR1 gene, encoding the principal skeletal muscle sarcoplasmic reticulum calcium release channel (RyR1. Altered excitability and/or changes in calcium homeostasis within muscle cells due to mutation-induced conformational changes of the RyR protein are considered the main pathogenetic mechanism(s. The diagnosis of CCD is based on the presence of suggestive clinical features and central cores on muscle biopsy; muscle MRI may show a characteristic pattern of selective muscle involvement and aid the diagnosis in cases with equivocal histopathological findings. Mutational analysis of the RYR1 gene may provide genetic confirmation of the diagnosis. Management is mainly supportive and has to anticipate susceptibility to potentially life-threatening reactions to general anaesthesia. Further evaluation of the underlying molecular mechanisms may provide the basis for future rational pharmacological treatment. In the majority of patients, weakness is static or only slowly progressive, with a favourable long-term outcome.

  5. Core and Geodynamo Evolution and the Influence of Potassium

    Science.gov (United States)

    Nimmo, F.; Price, G. D.; Brodholt, J.

    2002-12-01

    In his penultimate paragraph, Birch (1952) notes that the growth of the inner core is controlled by its melting curve, which ``. . . has implications for the `hydromagnetic' theories of the Earth's magnetism''. Although the terminology has changed, the relationship between the growth of the inner core and the geodynamo is still an area of active research, and is still limited by our imperfect understanding of core properties. The ability of the Earth's core to sustain a geodynamo depends on the entropy produced by core cooling and/or solidification [1,2]. The rate of cooling depends on the rate at which the mantle extracts heat from the core. In this contribution we model the coupled thermal evolution of the core and mantle [3,4,5] to investigate the circumstances under which the geodynamo can have been sustained for at least 3~Ga. In particular, we use improved estimates of core properties [6], and examine the effect of potassium in the core, as suggested by recent theoretical [7] and experimental [8] studies. Models without potassium in the core and with realistic present-day temperature and viscosity structures can sustain a geodynamo. However, for the nominal core parameters these models produce an inner core which is too large. For reasonable mantle viscosities, the core cools too rapidly; a reduced cooling rate produces a smaller inner core but requires unreasonable viscosities. The robustness of this result depends mainly on uncertainties in the solidus temperature of the core and the mean thermal expansivity of the mantle. Introducing potassium into the core retards the rate of core growth [7] and provides an additional source of entropy [1]. For a core potassium content of 100-400ppm [8], the criteria of mantle and core temperature and viscosity structure, inner core radius and geodynamo generation can all be satisfied. [1] Gubbins, D. et al., GJRAS 59, 57-99, 1979. [2] Buffett, B.A. et al., JGR 101, 7989-8006, 1996. [3] Mollett, S., GJRAS 76, 653

  6. Core-seis: a code for LMFBR core seismic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chellapandi, P.; Ravi, R.; Chetal, S.C.; Bhoje, S.B. [Indira Gandhi Centre for Atomic Research, Kalpakkam (India). Reactor Group

    1995-12-31

    This paper deals with a computer code CORE-SEIS specially developed for seismic analysis of LMFBR core configurations. For demonstrating the prediction capability of the code, results are presented for one of the MONJU reactor core mock ups which deals with a cluster of 37 subassemblies kept in water. (author). 3 refs., 7 figs., 2 tabs.

  7. Core Exercises: Why You Should Strengthen Your Core Muscles

    Science.gov (United States)

    Healthy Lifestyle Fitness You know core exercises are good for you — but do you include core exercises in your fitness routine? Here's why ... 18, 2014 Original article: http://www.mayoclinic.org/healthy-lifestyle/fitness/in-depth/core-exercises/art-20044751 . Mayo Clinic Footer Legal Conditions and ...

  8. Core Graduate Courses: A Missed Learning Opportunity?

    CERN Document Server

    Singh, Chandralekha

    2016-01-01

    An important goal of graduate physics core courses is to help students develop expertise in problem solving and improve their reasoning and meta-cognitive skills. We explore the conceptual difficulties of physics graduate students by administering conceptual problems on topics covered in undergraduate physics courses before and after instruction in related first year core graduate courses. Here, we focus on physics graduate students' difficulties manifested by their performance on two qualitative problems involving diagrammatic representation of vector fields. Some graduate students had great difficulty in recognizing whether the diagrams of the vector fields had divergence and/or curl but they had no difficulty computing the divergence and curl of the vector fields mathematically. We also conducted individual discussions with various faculty members who regularly teach first year graduate physics core courses about the goals of these courses and the performance of graduate students on the conceptual problems...

  9. Improvement on controllable fabrication of streptavidin-modified three-layer core-shell Fe3O4@SiO2@Au magnetic nanocomposites with low fluorescence background.

    Science.gov (United States)

    Jiang, Hongrong; Zeng, Xin; Xi, Zhijiang; Liu, Ming; Li, Chuanyan; Li, Zhiyang; Jin, Lian; Wang, Zhifei; Deng, Yan; He, Nongyue

    2013-04-01

    In present study, we put forward an approach to prepare three-layer core-shell Fe3O4@SiO2@Au magnetic nanocomposites via the combination of self-assembling, seed-mediated growing and multi-step chemical reduction. The Fe3O4@SiO2@Au magnetic nanocomposites were analyzed and characterized by transmission electron microscope (TEM), scanning electronic microscope (SEM), energy dispersive spectrometer analysis (EDS), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM), and ultraviolet and visible spectrophotometer (UV-Vis). TEM and SEM characterizations showed that the FeO4@SiO2@Au nanocomposites were obtained successfully with three-layer structures, especially a layer of thin, smooth and continuous gold shell. The average diameter of Fe3O4@SiO2@Au nanocomposites was about 600 nm and an excellent dispersity was observed for the as-prepared nanoparticles. EDS characterizations demonstrated that the nanocomposites contained three elements of the precursors, Fe, Si, and Au. Furthermore, FT-IR showed that the silica and gold shell were coated successfully. UV-Vis and VSM characterizations showed that the Fe3O4@SiO2@Au nanocomposites exhibited good optical and magnetic property, and the saturation magnetization was 25.76 emu/g. In conclusion, the Fe3O4@SiO2@Au magnetic nanocomposites with three-layer core-shell structures were prepared. Furthermore, Fe3O4@SiO2@Au magnetic nanocomposites were modified with streptavidin (SA) successfully, and it was validated that they performed low fluorescence background, suggesting that they should have good applications especially in bioassay based on fluorescence detection through bonding the biotinylated fluorescent probes.