bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic expression of DKK1 protein in the process whereby Epimedium‐derived flavonoids up‐regulate osteogenic and down‐regulate adipogenic differentiation of bone marrow stromal cells in ovariectomized rats
Authors: Xu Ying‐xing , Xu Bing , Wu Cheng‐liang , Wu Yan , Tong Pei‐jian , Xiao Lu‐wei
Published: April 2011

Objective:  To observe the dynamic expression of DKK1 protein in the process whereby Epimedium‐derived flavonoids (EFs) regulate the balance between osteogenic and adipogenic differentiation of bone marrow stromal cells in ovariectomized rats, and to provide experimental evidence for the mechanism of EFs in the treatment of postmenopausal osteoporosis.

Methods:  Bone marrow stromal cells from ovariectomized rats were separated and cultivated in osteoinductive or liquid medium for 15 days in vitro. EFs (10 µg/mL) were applied to both cultures. Alkaline phosphatase (ALP) staining, ALP activity determination, Oil Red O staining and fluorescence quantitative polymerase chain reaction were used to determine the influence of EFs on osteogenic and adipogenic differentiation of bone marrow stromal cells in ovariectomized rats. Moreover, in order to explore the exact mechanism of EFs on osteogenic and adipogenic differentiation of bone marrow stromal cells in ovariectomized rats, enzyme linked immunosorbent assay was used to determine the dynamic expression of DKK1 protein in this process.

Results:  EFs increased activity of ALP and mRNA expression of Runx2 (early osteoblast differentiation factor) and decreased mRNA expression of PPARγ‐2 (key factor of fat generation). Importantly, EFs down‐regulated expression of DKK1 protein in an osteogenic induction medium and inhibited up‐regulation of DKK1 protein in an adipogenic induction medium.

Conclusion:  EFs regulate the balance between osteogenic and adipogenic differentiation of bone marrow stromal cells in ovariectomized rats by down‐regulating expression of DKK1 protein. This may be an important molecular mechanism of EFs in the context of treatment of postmenopausal osteoporosis.
An examination of hardiness throughout the sport injury process
Authors: Wadey Ross , Evans Lynne , Hanton Sheldon , Neil Rich
Published: April 2011

Objectives. This primary objective of the study was to examine the direct and moderating effects of hardiness on the prediction of sport injury, and the direct and indirect effects of hardiness on athletes’ responses to injury.

Design. This study employed a longitudinal methodological design. Specifically, the injury status of 694 asymptomatic participants was monitored for 2 years. From the original sample, 104 athletes subsequently became injured and then completed a number of questionnaires throughout their recovery.

Methods. Logistic regression, Pearson product‐moment correlation and Preacher and Hayes's (2008) bootstrapping procedure were used to analyse the data.

Results. Findings revealed a direct and moderating effect of hardiness on the prediction of injury. Hardiness was also found to positively correlate with desirable, and negatively correlate with undesirable post‐injury psychological responses and coping strategies throughout recovery. Finally, problem‐focused coping was found to mediate certain effects of hardiness on injured athletes’ psychological responses.

Conclusions. These findings have important implications for practitioners who have a vested interest in the health and well‐being of those who participate in sport and exercise in terms of minimizing rates of injury occurrence and/or facilitating recovery from injury.
Shakedown Limit Loads for 90 Degree Scheduled Pipe Bends Subjected to Steady Internal Pressure and Cyclic Bending Moments
Authors: Abdalla Hany F. , Megahed Mohammad M. , Younan Maher Y. A.
Published: April 2011

A simplified technique for determining the shakedown limit load for a long radius 90 deg pipe bend was previously developed (Abdalla, H. F., et al., 2006, “Determination of Shakedown Limit Load for a 90 Degree Pipe Bend Using a Simplified Technique,” ASME J. Pressure Vessel Technol., 128, pp. 618–624; Abdalla, H. F., et al., 2007, “Shakedown Limits of a 90-Degree Pipe Bend Using Small and Large Displacement Formulations,” ASME J. Pressure Vessel Technol., 129, pp. 287–295). The simplified technique utilizes the finite element (FE) method and employs the small displacement formulation to determine the shakedown limit load (moment) without performing lengthy time consuming full cyclic loading finite element simulations or utilizing conventional iterative elastic techniques. The shakedown limit load is determined through the calculation of residual stresses developed within the pipe bend structure. In the current paper, a parametric study is conducted through applying the simplified technique on three scheduled pipe bends, namely, nominal pipe size (NPS) 10 in. Sch. 20, NPS 10 in. Sch. 40 STD, and NPS 10 in. Sch. 80. Two material models are assigned, namely, an elastic perfectly plastic (EPP) material and an idealized elastic-linear strain hardening material obeying Ziegler’s linear kinematic hardening (KH) rule. This type of material model is termed in the current study as the KH-material. The pipe bends are subjected to a spectrum of steady internal pressure magnitudes and cyclic bending moments. The cyclic bending includes three different loading patterns, namely, in-plane closing, in-plane opening, and out-of-plane bending moment loadings of the pipe bends. The shakedown limit moments outputted by the simplified technique are used to generate shakedown diagrams of the scheduled pipe bends for the spectrum of steady internal pressure magnitudes. A comparison between the generated shakedown diagrams for the pipe bends employing the EPP- and the KH-materials is presented. Relatively higher shakedown limit moments were recorded for the pipe bends employing the KH-material at the medium to high internal pressure magnitudes.
Data-Driven Fault Detection in Aircraft Engines With Noisy Sensor Measurements
Authors: Sarkar Soumik , Jin Xin , Ray Asok
Published: April 2011

An inherent difficulty in sensor-data-driven fault detection is that the detection performance could be drastically reduced under sensor degradation (e.g., drift and noise). Complementary to traditional model-based techniques for fault detection, this paper proposes symbolic dynamic filtering by optimally partitioning the time series data of sensor observation. The objective here is to mask the effects of sensor noise level variation and magnify the system fault signatures. In this regard, the concepts of feature extraction and pattern classification are used for fault detection in aircraft gas turbine engines. The proposed methodology of data-driven fault detection is tested and validated on the Commercial Modular Aero-Propulsion System Simulation (C-MAPSS) test-bed developed by NASA for noisy (i.e., increased variance) sensor signals.
A Validated Modular Model for Hydraulic Actuation in a Pushbelt Continuously Variable Transmission
Authors: van der Meulen Stan , van Iperen Rokus , de Jager Bram , Veldpaus Frans , van der Sluis Francis , Steinbuch Maarten
Published: April 2011

A reduction in the fuel consumption of a passenger car with a pushbelt continuously variable transmission (CVT) can be established via optimization of the hydraulic actuation system. This requires a model of the dynamic characteristics with low complexity and high accuracy, e.g., for closed-loop control design, for closed-loop simulation, and for optimization of design parameters. The hydraulic actuation system includes a large number of hydraulic components and a model of the dynamic characteristics is scarce, which is caused by the complexity, the nonlinearity, and the necessity of a large number of physical parameters that are uncertain or unknown. In this paper, a modular model for the hydraulic actuation system on the basis of first principles is constructed and validated, which is characterized by a relatively low complexity and a reasonably high accuracy. A modular approach is pursued with respect to the first principles models of the hydraulic components, i.e., a hydraulic pump, spool valves, proportional solenoid valves, channels, and hydraulic cylinders, which reduces complexity and improves transparency. The model parameters are either directly provided, directly measured, or identified. The model of the hydraulic actuation system is composed of the models of the hydraulic components and is experimentally validated by means of measurements that are obtained from a production pushbelt CVT. Several experiment types are considered. The correspondence between the measured and simulated responses is fairly good.
Design of a Test
Rig for Vibration Control of Oil Platforms Using Magneto-Rheological
Dampers
Authors: Karkoub Mansour , Lamont Lisa
Ann , El
Chaar Lana
Published: April 2011

Offshore steel structures are widely used around the world, e.g., in Gulf of Mexico, the Middle East, and the North Sea. These structures are costly to build, and any damage to them could be catastrophic financially and environmentally. There are many factors that could possibly affect the health of these steel structures, particularly hydrodynamic forces. These forces cause the structure to vibrate and in the long run could lead to fatigue failure. Therefore, measures have to be taken in order to prevent these structures from failing. Magneto-rheological (MR) dampers are proven as a feasible alternative to reducing structural vibrations. An experimental setup is built in our laboratory to improve the dynamic modeling of steel jacketlike structures and study the effectiveness of MR dampers in decreasing the hydrodynamically induced vibrations. The structure is analyzed theoretically and experimentally, and the results are presented here.
Output Regulation for Output Feedback Systems With iISS Inverse Dynamics
Authors: Xu Dabo , Huang Jie
Published: April 2011

This paper develops an approach to dealing with the global robust output regulation problem for a class of nonlinear systems with integral input-to-state stable (iISS) inverse dynamics by using output feedback control. As iISS condition is strictly weaker than the ISS condition, the result of this paper applies to a larger class of nonlinear systems.
Investigations on the Rotordynamic Characteristics of a Hole-Pattern Seal Using Transient CFD and Periodic Circular Orbit Model
Authors: Yan Xin , Li Jun , Feng Zhenping
Published: April 2011

Numerical investigations on the rotordynamic characteristics of a typical hole-pattern seal using transient three-dimensional Reynolds-averaged Navier–Stokes (RANS) solution and the periodic circular orbit model were conducted in this work. The unsteady solutions combined with mesh deformation method were utilized to solve the three-dimensional RANS equations and obtain the transient reaction forces on a typical hole-pattern seal rotor at five different excitation frequencies. The relation between the periodic reaction forces and frequency dependent rotordynamic coefficients of the hole-pattern seal was obtained by considering the rotor with a periodic circular orbit (including forward orbit and backward orbit) of the seal center. The rotordynamic coefficients of the hole-pattern seal were then solved based on the obtained unsteady reaction forces and presented numerical method. Compared with the experimental data, the predicted rotordynamic coefficients of the hole-pattern seal are more agreeable with the experiment than that of the ISO-temperature (ISOT) bulk flow analysis and numerical approach with one-direction-shaking model. Furthermore, the unsteady leakage flow characteristics in the hole-pattern seal were also illustrated and discussed in detail.
Drill-String Dynamics: Reduced-Order Models and Experimental Studies
Authors: Liao Chien-Min , Balachandran Balakumar , Karkoub Mansour , Abdel-Magid Youssef L.
Published: April 2011

In this article, reduced-order models of a drill-string system are developed, the predictions of these models are studied, and qualitative comparisons are made with experimental studies. The reduced-order models allow for radial, bending, and torsion motions of a flexible drill string and stick-slip interactions between the drill string and an outer shell. Qualitative changes in the system motions are studied with respect to the rotation speed of the drill string and the friction coefficient between the drill string and the outer shell. The nonlinear motions predicted by the model are in agreement with the experimental observations, and these studies suggest that there may be preferred friction coefficient values for which most of the drill-string motions occur close to the center of a borehole. These modeling and experimental studies can serve as an important basis for furthering our understanding of drill-string dynamics and schemes for controlling them.
Investigation of Colloid-Facilitated Effects on the Radionuclides Migration in the Fractured Rock With a Kinetic Solubility-Limited Dissolution Model
Authors: Jen Chun-Ping , Tien Neng-Chuan
Published: April 2011

Nuclides can move with the groundwater either as solutes or colloids, where the latter mechanism generally results in much shorter traveling time as they interact strongly with solid phases, such as actinides. It is therefore essential to assess the relative importance of these two transport mechanisms for different nuclides. The relative importance of colloids depends on the nature and concentration of colloids in groundwater. Plutonium (Pu), neptunium (Np), uranium (U) and americium (Am) are four nuclides of concern for long-term emplacement of nuclear wastes at potential repository sites. If attached to iron oxide, clay or silica colloids in groundwater. Strong sorption of the actinides by colloids in groundwater may facilitate transport of these nuclides along potential flow paths. Solubility-limited dissolution model models can be used to determine the release of the safety assessment for nuclear waste in geological disposal sites. The present study investigates the effect of colloid on the transport of solubility limited nuclide under the kinetic solubility limited dissolution (KSLD) boundary condition in fractured media. The release rate of nuclide would proportional to the difference between the saturation concentration and the inlet aqueous concentration of nuclide. The presence of colloids could decrease the aqueous concentration of nuclide and thus could increase the release flux of nuclide from the waste form.
A GoldSim Modeling Approach to Safety Assessment of an LILW Repository System
Authors: Lee Youn Myoung , Jeong Jongtae , Choi Jongwon
Published: April 2011

A program for the safety assessment and performance evaluation of a low- and intermediate level waste (LILW) repository system has been developed by utilizing GoldSim [1]. By utilizing this nuclide transport in the near- and far-field of a repository as well as a transport through a biosphere under various natural and manmade disruptive events affecting a nuclide release are modeled and evaluated. To demonstrate its usability, some illustrative cases under the selected scenarios including the influence of degradation of manmade barriers, pumping well drilling, and the natural disruptive events such as a sudden formation of preferential flow pathway have been investigated and illustrated for a hypothetical LILW repository. Even though all the parameter values applied to a hypothetical repository are assumed without any real base, the illustrative cases could be informative especially when seeing the result of the probabilistic calculation or sensitivity studies with various scenarios that possibly happen for nuclide release and further transport.
Optimization of Quantitative Waste Volume Determination Technique for Hanford Waste Tank Closure
Authors: Monts David L. , Jang Ping-Rey , Long Zhiling , Okhuysen Walter P. , Norton Olin P. , Gresham Lawrence L. , Su Yi , Lindner Jeffrey S.
Published: April 2011

The Hanford Site is currently in the process of an extensive effort to empty and close its radioactive single-shell and double-shell waste storage tanks. Before this can be accomplished, it is necessary to know how much residual material is left in a given waste tank and the uncertainty with which that volume is known. The Institute for Clean Energy Technology (ICET) at Mississippi State University is currently developing a quantitative in-tank imaging system based on Fourier Transform Profilometry, FTP. FTP is a non-contact, 3-D shape measurement technique. By projecting a fringe pattern onto a target surface and observing its deformation due to surface irregularities from a different view angle, FTP is capable of determining the height (depth) distribution (and hence volume distribution) of the target surface, thus reproducing the profile of the target accurately under a wide variety of conditions. Hence FTP has the potential to be utilized for quantitative determination of residual wastes within Hanford waste tanks. In this paper, efforts to characterize the accuracy and precision of quantitative volume determination using FTP and the use of these results to optimize the FTP system for deployment within Hanford waste tanks are described.
Spatial Variability and Parametric Uncertainty in Performance Assessment Models
Authors: Pensado Osvaldo , Mancillas James , Painter Scott , Tomishima Yasuo
Published: April 2011

The problem of defining an appropriate treatment of distribution functions (which could represent spatial variability or parametric uncertainty) is examined based on a generic performance assessment model for a high-level waste repository. The generic model incorporated source term models available in GoldSim®, the TDRW code for contaminant transport in sparse fracture networks with a complex fracture-matrix interaction process, and a biosphere dose model known as BDOSE™. Using the GoldSim framework, several Monte Carlo sampling approaches and transport conceptualizations were evaluated to explore the effect of various treatments of spatial variability and parametric uncertainty on dose estimates. Results from a model employing a representative source and ensemble-averaged pathway properties were compared to results from a model allowing for stochastic variation of transport properties along streamline segments (i.e., explicit representation of spatial variability within a Monte Carlo realization). We concluded that the sampling approach and the definition of an ensemble representative do influence consequence estimates. In the examples analyzed in this paper, approaches considering limited variability of a transport resistance parameter along a streamline increased the frequency of fast pathways resulting in relatively high dose estimates, while those allowing for broad variability along streamlines increased the frequency of “bottlenecks” reducing dose estimates. On this basis, simplified approaches with limited consideration of variability may suffice for intended uses of the performance assessment model, such as evaluation of site safety.
Effects of Nitrate on Nuclide Solubility for Co-Location Disposal of TRU Waste and HLW
Authors: Mihara Morihiro , Nakazawa Toshiyuki , Yamada Norikazu , Kamei Gento
Published: April 2011

Part of TRU waste includes a large amount of nitrate salt, the effects of which have to be evaluated in a safety assessment of co-location disposal with high level radioactive waste (HLW). High concentrations of nitrate ions from TRU waste might affect the solubility of different radionuclides in the HLW. In the current study, the effects of nitrate salt on radionuclide solubility were investigated experimentally. Solubility experiments of important and redox sensitive radionuclides, Tc(IV), Np(IV) and Se(0), were performed using various concentrations of sodium nitrate (NaNO3) and of Np(V) in NaNO3 solutions to investigate complex formation with NO3− ions. Solubility experiments of Pd(II), Sn(IV) and Nb(V) using ammonium chloride (NH4Cl) solution were also undertaken to investigate complex formation with NH3/NH4+ ions. No significant solubility enhancement was observed for Np and Se. Tc solubility in ≥0.1 mol/dm3 NaNO3 solution increased due to oxidation by nitrate ions. An increase of Np(V) solubility was expected by the chemical equilibrium model calculation with JNC-TDB, however, solubility enhancement by complex formation of Np(V) with nitrate ions was not observed. Solubility enhancement by complex formation of Sn and Nb were also not observed, only Pd solubility was increased by complex formation with NH3/NH4+ ions.
Hydrogeological Characterization Based on Long Term Groundwater Pressure Monitoring
Authors: Daimaru Shuji , Takeuchi Ryuji , Takeda Masaki , Ishibashi Masayuki
Published: April 2011

The Mizunami Underground Research Laboratory (MIU) is now under construction by the Japan Atomic Energy Agency in the Tono area of central Japan. The MIU project is being implemented in three overlapping Phases: Surface-based Investigation (Phase I), Construction (Phase II) and Operation (Phase III). The changes of groundwater pressure due to shaft excavation can be considered analogous to a large-scale pumping test. Therefore, there is the possibility that the site scale groundwater field (several km square) can be approximated by the long-term groundwater pressure monitoring data from Phase II. Based on the monitoring observations, hydrogeological characteristics were estimated using the s-log(t/r2) plot based on the Cooper-Jacob straight line method. Results of the s-log(t/r2) plots are as follows. The groundwater flow field around the MIU construction site is separated into domains by an impermeable fault. In other words, the fault is a hydraulic barrier. Hydraulic conductivity calculated from s-log(t/r2) plots are in the order of 1.0E−7(m/s). The above results from the long term monitoring during Phase II are a verification of the hydrogeological characteristics determined in the Phase I investigations.
An Analytical Model on the Sealing Performance of Space for the Design of Buffer Material and Backfill Material
Authors: Sato Haruo
Published: April 2011

The self-sealing function of the clearances between buffer material and overpack and tunnel wall or disposal pit wall and between backfill material and tunnel wall is expected for bentonite which will be used as buffer material and part of the backfill material. In this study, an analytical theory on the clearance filling performance for both materials was constructed. Volumetric swelling ratio of bentonite (Rvs) and maximum clearance ratio that bentonite can fill clearance (Rsmax) were calculated against dry density for different montmorillonite and silica sand contents of bentonites in distilled water and saline water conditions (Horonobe groundwater and synthetic seawater). Both Rvs and Rsmax values decreased with decreasing montmorillonite content and decreased in saline water conditions. The Rvs values in the Horonobe groundwater (ionic strength IS = 0.207 M) were approximately a half of those in distilled water and those in synthetic seawater (IS = 0.64 M) were approximately a half of those in the Horonobe groundwater. In the case that actual sealing performance is judged, not only clearance filling, but also hydraulic conductivity etc. after the clearance was filled must be considered. In the design of buffer material and backfill material, those parameters must be systematically taken into account.
Modelling of Motorway Tunnels Scenario for Utilization of Conditionally Released Radioactive Materials
Authors: Hrncˇi´rˇ Toma´sˇ , Pa´nik Michal , Necˇas Vladimi´r
Published: April 2011

Considerable amount of solid radioactive waste with radioactivity slightly above the limits for unconditional release is generated during the decommissioning of the nuclear installations. Conditional release deals with precisely this type of materials with activity slightly above limits in order to save considerable financial resources, which would be otherwise spend on treatment, conditioning and disposal of these materials at appropriate repository. The basic principles of conditional release as well as possibilities of reusing of the conditionally released materials are described. One of these possibilities of the reusing was chosen and application proposal of conditional release of metal waste - steel reinforcement in the concrete, which could be used for construction of motorway tunnels, was created. The computer code Visiplan 4.0 3D ALARA planning tool software was used for the calculation of effective individual dose for personnel constructing the tunnel and for critical group related to scenario. Particular models for individual scenarios of conditional release have been developed within the scope of this software code. The aim of the paper is to determine a level of the radioactivity of conditional released materials to avoid over exceeding the value of annual individual effective dose 10μSv/year established by international recommendations.
Evaluation of Behavior of Rare Earth Elements Based on Determination of Chemical State in Groundwater in Granite
Authors: Yamamoto Yuhei , Aosai Daisuke , Mizuno Takashi
Published: April 2011

The chemical state of rare earth elements (REEs) in groundwater was determined by a combination of ultrafiltration techniques maintaining in–situ pressures and anaerobic conditions, speciation considering contribution of natural organic matter, and fingerprinting using REE patterns of the stability constants for probable complexes of REEs in groundwater. Groundwater samples were collected from a horizontal borehole at a depth of 200 mbGL (meter below ground level) in the Mizunami Underground Research Laboratory (MIU), Gifu, Japan. Spectroscopic analysis for colloidal matter on a membrane filter was also conducted to estimate chemical properties of colloidal ligands. Results of this study suggest that REEs–humic complexes are the dominant chemical states of REEs in this groundwater. The presence of humic substances in groundwater was also confirmed by spectroscopic analysis. Thus, it is expected that chemical behavior of REEs mainly is dependent on humic substances. The information of chemical state of REEs is useful for prediction of behavior of trivalent actinides in groundwater.
Site Selection for a Geological Disposal in France: An Approach of Convergence
Authors: Ouzounian Gerald , Miguez Roberto , Tison Jean-Louis
Published: April 2011

On December 1991, the French National Assembly passed the French Waste Management Research Act, authorizing a 15 year research program of three options for HLW: separation and/or transmutation, long-term storage, and geologic disposal. On June 2006, the “Planning Act on the sustainable management of radioactive materials and waste” sets a new framework and new aims to the above mentioned options. This paper deals only with the geologic disposal research program. In a step by step approach, this program has been broken down into three phases having intermediate goals (objectives): site selection for an Underground research Laboratory (URL), potential disposal feasibility, potential reversible disposal design. The first step of the research program aimed at URL site selection. From 1994 to 1996, Andra carried out geological-characterization work in four districts. This enabled to make the Request for Licensing and Operation of the laboratory facility on three sites. During this phase, wells, 2D seismic campaigns and land studies of geologic outcrops were the essential activities. The result was the selection of the most suitable site for the implementation of an underground laboratory. Main results on Bure URL will be presented in the paper. In the second phase the research program targeted the safety and technical feasibility of a potential reversible disposal somewhere in Meuse and Haute Marne districts site, chosen by the government in 1998. Andra conducted geologic survey during the URL shaft construction and experiments in drifts at depths of 445 and 490 m. This program allowed consolidating the knowledge already acquired: geological environment, stability of the rock, containment properties and it confirms that the rock will maintain its qualities. The 2005 Progress Report presents the results of this phase. The main conclusion is that a potential disposal facility may be safely constructed over a zone around the URL, called transposition zone (about 250 km2). The paper will present the most important results in this phase. From 2006, the third phase of the program, the activities were oriented, inside the transposition zone, to determine a smaller zone in which a potential disposal facility could be designed. In 2009, Andra issued a proposal describing such a zone to the French authorities. In this paper, the main results of this phase will be presented. Finally, the next steps towards a final implementation will be given.
Selective Uptake of Palladium From High-Level Liquid Wastes by Hybrid Microcapsules Enclosed With Insoluble Ferrocyanides
Authors: Mimura Hitoshi , Sakakibara Takashi , Yan Wu , Niibori Yuichi , Koyama Shin-ichi , Ohnishi Takashi
Published: April 2011

Fine crystalline powders of KCuFC were immobilized with alginate gel polymers by sol-gel methods. The uptake properties of KCuFC-microcapsules (KCuFC-MC) were examined by batch and column methods. The size of KCuFC-MC particle was estimated to be about 1 mm in diameter, and KCuFC powders were uniformly dispersed in KCuFC-MC particles. The uptake rate of Pd2+ for KCuFC-MC was attained within 3 d, and the uptake of Pd2+ was found to be independent of the temperature and coexisting HNO3 concentration. As for the breakthrough properties of Pd2+ through a column packed with KCuFC-MC, a breakpoint of 5% breakthrough was enhanced with lowering of flow rate and independent of coexisting HNO3 concentration. The Pd2+ ions were selectively adsorbed in the KCuFC crystal phase, while other metal ions such as Ru(NO)3+ and ZrO2+ were absorbed in the alginate phase. High uptake percentage of 98.6% was obtained by using the dissolved solutions of spent fuel from FBR-JOYO (119 GWd/t, JAEA). The alginate film enclosing KZnFC was further prepared by using the support of cellulose filter paper, where the Pd2+ ions were selectively adsorbed on the KZnFC-MC film. The alginate film enclosing insoluble ferrocyanides are predicted for the selective separation of Pd2+ as an ion-exchange filter. Thus, the microcapsules enclosing insoluble ferrocyanides are effective for the selective separation of Pd2+ from high-level liquid waste (HLLW).
VUJE Experience With Cementation of Liquid and Wet Radioactive Waste
Authors: Krava´rik Kamil , Holicka´ Zuzana , Peka´r Anton , Zˇatkula´k Milan
Published: April 2011

Liquid and wet LLW generated during operation as well as decommissioning of NPPs is treated with different methods and fixed in a suitable fixation matrix so that a final product meets required criteria for its disposal in a final repository. Cementation is an important process used for fixation of liquid and wet radioactive waste such as concentrate, spent resins and sludge. Active cement grout is also used for fixation of low level solid radioactive waste loaded in final packing containers. VUJE Inc. has been engaged in research of cementation for long. The laboratory for analyzing radioactive waste properties, prescription of cementation formulation and estimation of final cement product properties has been established. Experimental, semi-production cementation plant has been built to optimize operation parameters of cementation. VUJE experience with cementation of liquid and wet LLW is described in the presented paper. VUJE has assisted in commissioning of Jaslovske´ Bohunice Treatment Centre. Cement formulations for treatment of concentrate, spent resins and sludge have been developed. Research studies on the stability of a final concrete packaging container for disposal in repository have been performed. Gained experience has been further utilized for design and manufacture of several cementation plants for treatment of various liquid and wet LLW. Their main technological and technical parameters as well as characterization of treated waste are described in the paper. Applications include the Mochovce Final Treatment Centre, Movable Cementation Facility utilizing in-drum mixing for treatment of sludge, Cementation Facility for treatment of tritiated water in Latvia and Cementation Facility for fixation of liquid and solid institutional radioactive waste in Bulgaria, which utilizes lost stirrer mixer.
Study of LPOP Residue on Resin Mineralization and Solidification
Authors: Katagiri Gen-ichi , Fujisawa Morio , Sano Kazuya , Higashiura Norikazu
Published: April 2011

Fuji Electric had developed the low pressure oxygen plasma technology for mild decomposition and mineralization of an organic material such as ion exchange resin. This method is suitable for radioactive spent resin volume/weight reduction and stabilization for final disposal. On this process, the ion-exchange resins are vaporized and decomposed into gas-phase with pyrolysis, and then, they are decomposed and oxidized with low-pressure plasma activity based on oxygen. And this process is achieved under moderate condition for radio active waste. • incinerate temperature: 400–700 deg C; • low-pressure (low-temperature) plasma condition: 10–50 Pa. From the result of this process, named of LPOP(low pressure oxidation process) by the inductively coupled plasma, we have confirmed that the process is applicable for organic fireproof waste including ion-exchange resin, and found that the used resin treatment performance is the same as cold test (using imitate spent resin) [1] [2] [3]. In this paper, the outline of the LPOP technology, and two research results on the possibility of solidification with cement of LPOP residue for geological disposes are reported. (1)Study of the residue chemical form after LPOP process (2)Study of the solidification character with cement.
Remediation of 153Gd-Contaminated Sand by Fulvic and Humic Materials Extracted From Fallen Cherry Leaves
Authors: Kubota Takumi
Published: April 2011

The remediation of sand contaminated with 153Gd has been investigated using natural organic substances extracted from fallen cherry leaves instead of artificial reagents. The initial fulvic and humic acid isolated from organic substances through acidic and basic treatments have a concentration of total organic carbon of 4500 mgC/L and 3340 mgC/L, and the capacities of their functional groups are 7.23 meq/gC and 2.76 meq/gC, respectively. The remediation capacity of both fulvic and humic acid is effective in the weakly acidic region. Remediation with a natural organic substance requires a much higher carbon concentration than EDTA owing to its weak complexation with metal ions. In comparison with the EDTA complexation constant, the experimental complexation constant (log β) of gadolinium with a natural organic substance at pH 5.5 was determined to be 10 at most.
Trends in Scenario Development Methodologies and Integration in NUMO’s Approach
Authors: Ebashi Takeshi , Ishiguro Katsuhiko , Wakasugi Keiichiro , Kawamura Hideki , Gaus Irina , Vomvoris Stratis , Martin Andrew J. , Smith Paul
Published: April 2011

The development of scenarios for quantitative or qualitative analysis is a key element of the assessment of the safety of geological disposal systems. As an outcome of an international workshop attended by European and the Japanese implementers, a number of features common to current methodologies could be identified, as well as trends in their evolution over time. In the late nineties, scenario development was often described as a bottom-up process, whereby scenarios were said to be developed in essence from FEP databases. Nowadays, it is recognised that, in practice, the approaches actually adopted are better described as top-down or “hybrid”, taking as their starting point an integrated (top-down) understanding of the system under consideration including uncertainties in initial state, sometimes assisted by the development of “storyboards”. A bottom-up element remains (hence the term “hybrid”) to the extent that FEP databases or FEP catalogues (including interactions) are still used, but the focus is generally on completeness checking, which occurs parallel to the main assessment process. Recent advances focus on the consistent treatment of uncertainties throughout the safety assessment and on the integration of operational safety and long term safety.
The Zwilag Plasma Facility: Five Years of Successful Operation
Authors: Heep Walter
Published: April 2011

This paper is about a treatment facility for low level radioactive wastes that operates with plasma technology. The first processing of low-level radioactive wastes from Swiss nuclear power plants marked the successful completion of the commissioning of this facility in March 2004. This process technology is derived from metallurgy. Its theoretical principles are based on plasma technology, which has been applied for quite some time outside the field of nuclear technology for the production of highly pure metal alloys and for the plasma synthesis of acetylene. The commercial operation of the plasma plant owned by Zwilag Zwischenlager Wu¨renlingen AG (Zwilag) has also enabled this technology to be used successfully for the first time in the nuclear field in a way that addresses the issue of radiation protection. In addition to a brief presentation of the technology used in the plant, the paper explains in detail how the process works under operating conditions. The plasma facility has been operating now for five years and was granted an unrestricted operating license in September 2009.
Assessing the Gas Transport Mechanisms in the Swiss L/ILW Concept Using Numerical Modeling and Supporting Experimental Work
Authors: Gaus Irina , Marschall Paul , Senger Rainer , Ewing John , Rueedi Joerg
Published: April 2011

In low/intermediate-level waste (L/ILW) repositories, anaerobic corrosion of metals and degradation of organic materials produce hydrogen, methane, and carbon dioxide. Gas accumulation and gas transport in a L/ILW repository is an important component in the safety assessment of proposed deep repositories in low-permeability formations. The dominant gas transport mechanisms are dependent on the gas overpressures as with increasing overpressure the gas transport capacity of the system increases. The dominant gas transport mechanisms occurring with increasing gas pressure within the anticipated pressure ranges are: diffusion of gas dissolved in pore water (1), two phase flow in the host rock and the excavation damaged zone (EDZ) whereby no deformation of the pore space occurs (2), gas migration within parts of the repository (if repository materials are appropriately chosen) (3) and pathway dilation (4). Under no circumstances the gas is expected to induce permanent fractures in the host rock. This paper focuses on the gas migration in parts of the repository whereby materials are chosen aimed at increasing the gas transport capacity of the backfilled underground structures without compromising the radionuclide retention capacity of the engineered barrier system (EBS). These materials with enhanced gas permeability and low water permeability can supplement the gas flow that is expected to occur through the EDZ and the host rock. The impact of the use of adapted backfill and sealing materials on the gas pressure build-up and the major gas paths were assessed using numerical two-phase flow models on the repository scale. Furthermore, both the gas and water fluxes as a function of time and gas generation rate can be evaluated by varying the physical properties of the materials and hence their transport capacity. Results showed that by introducing seals with higher gas permeability, the modelled gas flow is largely limited to the access tunnels and the excavation disturbed zone for the case of a very low permeability host rock. The bulk of the gas flows through the repository seal and the adjacent EDZ into the tunnel system. In addition to the demonstration of the gas flow in the seal and access tunnel system by numerical models, laboratory results confirm the high gas transport capacity of the sand/bentonite mixtures. In a next step a multi year demonstration scale experiment (GAST) at the Grimsel Test Site is envisioned.
Full-Scale Test of Overpack Closure Techniques for HLW Repository Operation: Welding Methods and UT Systems for Long-Term Structural Integrity of Weld Joints
Authors: Nakamura Ario , Asano Hidekazu , Kawakami Susumu , Ito Takashi , Furukawa Takashi , Fujisawa Kyosuke
Published: April 2011

Overpack, a high-level radioactive waste package for Japan’s geological disposal program, is required for preventing sealed vitrified waste from contact with groundwater for at least 1,000 years. The weld joint between the body and lid must also meet this requirement. Certain welding methods were examined for applicability through full-scale welding tests using various welding depths up to 190 mm and two different lid structures. Results show that generation of welding flaws must be considered unavoidable. Therefore, ultrasonic testing (UT) must be conducted on the assumption that weld flaws will be present. Such UT systems must be designed for natural defects. Several types of UT must be evaluated for detection and size estimation capability at depths ranging from the surface to the bottom of the weld joint. Certain UT methods were examined for their ability to detect natural defects that were created on the surface of and inside a 190-mm thick carbon steel specimen. Probability of detection (POD) of each UT method was calculated by comparing the results of UT and destructive examination. In consideration of the preferred range of scanning depth for each UT method, a concept that combines UT methods was proposed as a practical UT system for the overpack weld joint.
Effect of the Residual Heat Release of the Nuclear Waste Stored in an Unsaturated Zone on Radionuclide Release
Authors: Hamdan Lubna K. , Walton John C. , Woocay Arturo
Published: April 2011

Over time, nuclear waste packages disposed in geological repositories are expected to fail gradually due to localized and general corrosion. As a result, water will have access to the nuclear waste and radionuclides will be transported to the accessible environment by ground water. In this paper we consider a serious failure case in which penetrations at the top and bottom of the waste package will allow water to flow through it (flow-through model). We introduce a new conceptual model that examines the effect of the residual heat release of the nuclear waste stored in an unsaturated environment on radionuclide release. This model predicts that the evaporation of water at the hotter sheltered areas (from condensate and seepage) inside the failed waste package will create a capillary pressure gradient that drives water to wick with its dissolved and suspended contents toward these relict areas, effectively preventing radionuclides release. We drive a dimensionless group to estimate the minimum length of the sheltered areas required to sequester radionuclides and prevent their release. The implications of this model on the performance of the proposed repository at Yucca Mountain or unsaturated zone geological repositories in general are explored.
Design Options for HLW Repository Operation Technology: Part I—Demonstration and Evaluation of Remote Handling Technologies
Authors: Nakashima Hitoshi , Asano Hidekazu , Kawamura Hideki
Published: April 2011

The long-term safety of a geological repository for high-level radioactive waste (HLW) in Japan is achieved using a multi-barrier system, with emphasis on an engineered barrier system (EBS) consisting of bentonite-based buffer material and a steel overpack containing vitrified wastes. Providing a wide variety of technical options for repository operation, which can allow EBS construction under various repository conditions, is valuable for the volunteering approach to siting a HLW repository in Japan. In order to confirm technological applicability of candidate techniques and to evaluate compatibility in an operation system, full-scale tests of various remote-handling and-emplacement techniques for the EBS were conducted. The test results are summarized in the technical menu which is hierarchical structured database. Since the long-term performance of EBS is significantly influenced by remote handling and emplacement techniques for EBS, consistency of the operation technology must be evaluated from the view point of system standing. In this program, evaluation methodology was studied and several indexes, representing requirements for the repository operation and management, were identified. Indices include current technical availability, long-term safety of the resultant EBS, operational safety, engineering reliability, retrievability, etc., with expert assessment complementing a more quantitative evaluation.
Design Options for HLW Repository Operation Technology: Part III—Transportation and Horizontal Emplacement of Pre-Fabricated EBS Module (PEM)
Authors: Kawakami Susumu , Nakashima Hitoshi , Asano Hidekazu
Published: April 2011

As one of the repository operation technologies for high-level radioactive waste (HLW), the pre-fabricated engineered barrier system module (PEM) was carried out the examination of handling and emplacement technique for engineered barrier system (EBS). The PEM technology was examined to confirm technological applicability. The PEM is concept of the integration of EBS as the module in the surface facilities, and transporting the module underground facilities. This concept is the one of the candidate concepts of horizontal emplacement techniques for EBS in Japan. Therefore, PEM is the same level large size and heavy weight as EBS, and it is necessary to examine the applicability of handling and emplacement techniques. Full-scale level tests were performed to confirm the applicability of these techniques with the air bearing/air jack devices. In the tests, we prepared the testing devices of full-scale level size/weight and confirmed the applicability of these technologies as an elemental technology on the condition of considering the environment of an underground tunnel. The air bearing test that produced the surface-roughness of the tunnel environment was carried out the evaluation concerning the transportation performance of the air bearing. And, the air jack test was carried out the holding and emplacement of PEM. The repository operation technology with the air bearing/jack device was confirmed to execute the examination, and to apply to handling and emplacement technique for PEM.
Influences of Final Pipe Forming Process by Roll Bending Method on the Mechanical Properties of SAW Pipes
Authors: Zandipoor Afshin , Shamloo Reza
Published: April 2011

There are three main methods and process for forming pipes from plates “Roll Bending”, “JCOE” and “UOE”. In all of the above mentioned ways part of the pipe will remain flat, and can not achieve the desired curvature of the pipe. These areas are generally at the two longitudinal edges of the open seam pipes. For obviation of these flat areas at the longitudinal edges of the pipe, the pre forming machines for “JCOE” and “UOE” processes, and the post bending machine for “the Roll Bending” process are used. In the post bending machine the final shape of the pipes is determined based on the rate of the machine hoist pressure and the spaces between the rolling dies. These parameters can have various effects on the mechanical properties of the final welded pipes. In the research that has been conducted at SAFA Rolling & Pipe Mill Company, the amount of hoist pressure and the final shape of the open seam pipes in the post bending machine, and their influences on the mechanical properties of the welded pipes, have been investigated herein.