bluuebunny/crossref_metadata_2025 huggingface dataset:
Wakefieldite‐(Nd), a New Neodymium Vanadate Mineral in the Arase Stratiform Ferromanganese Deposit, Kochi Prefecture, Japan
Authors: Moriyama Takeru , Miyawaki Ritsuro , Yokoyama Kazumi , Matsubara Satoshi , Hirano Hideo , Murakami Hiroyasu , Watanabe Yasushi
Published: December 2010

Wakefieldite‐(Nd), NdVO4, is a new mineral found from the Arase stratiform ferromanganese deposit in Kochi Prefecture, Shikoku Island, Japan. It is the Nd‐dominant analogue of wakefieldite‐(Y) and wakefieldite‐(Ce). The ferromanganese ore specimen mainly consists of hematite and caryopilite, and wakefieldite‐(Nd) is typically enclosed in caryopilite. Wakefieldite‐(Nd) is tetragonal, I41/amd, a = 7.338(16) Å, c = 6.509(19) Å, V = 350.5(18) Å3, Z = 4. The four strongest lines in the X‐ray diffraction pattern [d(Å), I/I0, hkl] using a Gandolfi camera are (3.67, 100, 200); (2.74, 51, 112); (4.84, 27, 101) and (1.89, 25, 312). Chemical composition of wakefieldite‐(Nd) are V2O3 35.25, As2O3 0.93, SiO2 0.14, MnO 1.45, Fe2O3 0.41, Y2O3 2.87, La2O3 7.61, Ce2O3 7.37, Pr2O3 6.04, Nd2O3 26.79, Sm2O3 4.41, Eu2O3 1.36, Gd2O3 3.41, Tb2O3 0.22, Dy2O3 1.41, Er2O3 0.10, total 99.77 wt.%. The empirical formula is (Nd0.403La0.118Ce0.114Pr0.093Y0.064Sm0.064Mn0.052Gd0.048Eu0.020Dy0.019Fe0.013Tb0.003Er0.001)1.012(V0.981As0.020Si0.006)1.007O4 on the basis of O = 4. The calculated density is 4.782 g/cm3.

Microtexture and co‐existing relationship between wakefieldite‐(Nd) and caryopilite suggest that recrystallization and dehydration of Fe‐ and Mn‐oxyhydroxide led to the generation of hematite, caryopilite, rhodochrosite and wakefieldite‐(Nd) by the metamorphism during the accretion of the host unit of the Arase deposit. Chondrite‐normalized REE pattern of the host ferromanganese ore, which is regarded as oceanic metalliferous sediment in origin, shows negative Ce anomaly. Chemical composition of wakefieldite‐(Nd) reflects Ce‐depleted bulk composition of REE‐enriched ferromanganese ore.
A proliferative melanoma cell phenotype is responsive to RAF/MEK inhibition independent of BRAF mutation status
Authors: Zipser Marie C. , Eichhoff Ossia M. , Widmer Daniel S. , Schlegel Natalie C. , Schoenewolf Nicola L. , Stuart Darrin , Liu Weihua , Gardner Humphrey , Smith Paul D. , Nuciforo Paolo , Dummer Reinhard , Hoek Keith S.
Published: December 2010

Oncogenic mutations within the MAPK pathway are frequent in melanoma, and targeting of MAPK signaling has yielded spectacular responses in a significant number of patients that last for several months before relapsing. We investigated the effects of two different inhibitors of MAPK signaling in proliferative and invasive melanoma cell cultures with various mutations in the MAPK pathway. Proliferative melanoma cells were more susceptible to pathway inhibition than invasive phenotype cells, irrespective of BRAF mutation status, while invasive phenotype cell response was dependent on BRAF mutation status. Critically, MAPK pathway inhibition of proliferative phenotype cells resulted in acquisition of invasive phenotype characteristics. These results show that melanoma cell phenotype is an important factor in MAPK pathway inhibition response. This suggests that while current therapeutic strategies target proliferative melanoma cells, future approaches should also account for the invasive phenotype population.
Sphingosine-1-phosphate decreases melanin synthesis via microphthalmia-associated transcription factor phosphorylation through the S1P3 receptor subtype
Authors: Kim Dong-Seok , Park Seo-Hyoung , Jeong Yun-Mi , Kwon Sun-Bang , Miller Arlo J , Fisher David E , Park Kyoung-Chan
Published: December 2010

Objectives

Previously, we reported that sphingosine-1-phosphate (S1P) reduced melanin synthesis. In this study we have investigated S1P receptor-mediated extracellular signal-regulated protein kinase (ERK) activation and microphthalmia-associated transcription factor (MITF) phosphorylation.

Methods

To examine S1P-induced signalling pathways, electron and confocal microscopic studies, reverse transcription-polymerase chain reaction and Western blot analysis were performed.

Key findings

S1P phosphorylated MITF at Ser73, which may have resulted in a MITF mobility shift. Furthermore, 90 kDa ribosomal S6 kinase-1 (RSK-1) phosphorylation was observed after S1P treatment. In addition, PD98059 abrogated the S1P-induced MITF mobility shift and RSK-1 activation. In experiments with MITF mutants, it was shown that dual phosphorylation at Ser73 and Ser409 was indispensable for MITF degradation. We investigated further the actions of S1P on its specific receptors. The results showed that pertussis toxin completely abolished the hypopigmentary effects and ERK pathway activation by S1P, suggesting that S1P regulated melanogenesis via its receptor. The use of specific receptor antagonists indicated that the S1P3 receptor was dominantly involved in S1P-induced ERK activation and hypopigmentation.

Conclusions

The results suggested that S1P reduced melanin synthesis via S1P3 receptor-mediated ERK and RSK-1 activation, and subsequent MITF dual phosphorylation and degradation.
Testosterone is involved in mediating the effects of prenatal stress in male guinea pig offspring
Authors: Kapoor Amita , Matthews Stephen G.
Published: December 2010

Non‐technical summary

Studies in humans have demonstrated a link between stress during pregnancy and altered behaviour and stress reactivity in children. In guinea pigs, we have previously shown that a short period of maternal stress during gestation leads to increased anxiety, elevated basal cortisol levels and decreased testosterone levels in adult males. We hypothesized that restoring testosterone to normal levels in the adult males born to prenatally stressed mothers would reverse the changes in behaviours and endocrine function. We found differences in attention and anxiety‐related behaviours and basal stress endocrine activity between the prenatally stressed and control males. Administration of testosterone reversed the behavioural differences in the prenatally stressed offspring. There was, however, little effect of postnatal testosterone administration on stress‐related endocrine activity. This study provides new information to begin to address the mechanism underlying the interplay between prenatal stress, gonadal steroids and postnatal behaviours.
Angiotensin1‐9 antagonises pro‐hypertrophic signalling in cardiomyocytes via the angiotensin type 2 receptor
Authors: Flores‐Muñoz M. , Smith N. J. , Haggerty C. , Milligan G. , Nicklin S. A.
Published: December 2010

Non‐technical summary The renin–angiotensin system regulates the function of the cardiovascular system via the peptide hormone angiotensin II through a cellular receptor, the angiotensin type 1 receptor. Angiotensin II can become overactive and contribute to the development of cardiovascular disease, resulting in hypertension and other disorders such as enlargement of the heart muscle cells, termed cardiomyocyte hypertrophy. Here we demonstrate, for the first time, that an alternative angiotensin peptide, called angiotensin 1‐9, is able to inhibit cardiomyocyte hypertrophy induced by angiotensin II by binding and activating an alternative angiotensin receptor, the type 2 receptor. This has implications for our understanding of the renin–angiotensin system in normal cardiovascular function and in cardiovascular disease.
Reducing Overshoot in Human-Operated Flexible Systems
Authors: Vaughan Joshua , Jurek Paul , Singhose William
Published: December 2010

Input shaping accomplishes vibration reduction by slightly increasing the acceleration and deceleration periods of the command. The increase in the deceleration period can lead to system overshoot. This paper presents a new class of reduced-overtravel input shapers that are designed to reduce shaper-induced overtravel from human-operator commands. During the development of these new shapers, an expression for shaper-induced overtravel is introduced. This expression is used as an additional constraint in the input-shaper design process to generate the reduced-overtravel shapers. Experiments from a portable bridge crane verify the theoretical predictions of improved performance. Results from a study of eight industrial bridge crane operators indicate that utilizing the new reduced-overtravel input shapers dramatically reduces task completion time, while also improving positioning accuracy.
Calibration of Modular Reconfigurable Robots Based on a Hybrid Search Method
Authors: Lin Yu , Xi Fengfeng , Mohamed Richard Phillip , Tu Xiao-wei
Published: December 2010

Developed in this paper is a hybrid method for calibration of modular reconfigurable robots (MRRs). The underlying problem under study is unique to MRRs, that is, how to calibrate a set of MRR’s geometric parameters that are applicable to all feasible configurations. For this reason, a hybrid search method is developed to ensure a global search over the MRRs’ workspace for each feasible configuration. By combining a genetic algorithm method with a Monte Carlo method, this method includes three levels of search, namely, pose, workspace, and configuration-space. The final set of global solutions is generated progressively from the results of these three levels of search. The effectiveness of this method is demonstrated through a case study.
Gas Flow Simulations in Randomly Distributed Pebbles
Authors: Zhao Xiang , Montgomery Trent , Zhang Sijun
Published: December 2010

In this paper, computational fluid dynamics (CFD) gas flow simulations are carried out for the pebble bed reactor. In CFD calculations, geometry modeling and physical modeling are crucial to CFD results. The effects of the treatments of the interpebble contacts on gas flow fields and heat transfer are examined. A sensitivity analysis for the gap size is conducted with two spherical pebbles, in which the interpebble region is modeled by means of two types of interpebble gap and two kinds of direct contact. Both large eddy simulation and Reynolds-averaged Navier–Stokes models are employed to investigate the turbulent effects. It is found that the flow fields and relevant heat transfer are significantly dependent on the modeling of the interpebble region. The calculations indicate the complex flow structures present within the voids between the fuel pebbles.
Parametric Study on Single Shot and Overlapping Laser Shock Peening on Various Metals via Modeling and Experiments
Authors: Cao Yunfeng , Shin Yung C. , Wu Benxin
Published: December 2010

Laser shock peening (LSP) under water confinement regime involves several complicated physical phenomena. Among these phenomena, the interaction between laser and coating material during LSP is very important to the laser-induced residual stress, which has an important effect on the fatigue and corrosion properties of the substrate material. To gain a better understanding of this interaction, a series of experiments, including single shot, single-track overlapping, and multitrack overlapping LSP, has been carried out on various metals with different coatings. A 3D finite element model has also been developed to simulate the LSP process. Combining this with a previously developed confined plasma model, which has been verified by the experimental data from literature, the 3D finite element model is used to predict the residual stresses induced in the substrate material as well as the indentation profile on the substrate surface. The model prediction of indentation profiles is compared with the experimental data. The residual stresses in the depth direction are also validated against the X-ray diffraction measurement data for 4140 steel and Ti–6Al–4V, and good agreements are obtained for both predictions. The effect of process parameters on the residual stress is also investigated both experimentally and theoretically.
A Multifeature Approach to Tool Wear Estimation Using 3D Workpiece Surface Texture Parameters
Authors: Liao Yi , Stephenson David A. , Ni Jun
Published: December 2010

This work presents a new way to determine the condition of a cutting tool based on 3D texture parameters of workpiece surface. Recently, a laser holographic interferometer has been developed to rapidly measure a large workpiece surface and generate a 3D surface height map with micron level accuracy. This technique enables online surface measurement for machined workpieces. By measuring and analyzing workpiece surface texture, the interaction between the tool’s cutting edges and the workpiece surface can be extracted as a spatial signature. It can then be used as a warning sign for tool change because the workpiece produced by a heavily worn tool exhibits more irregularities in its surface texture than that produced by a normal tool. Multiple texture parameters such as image intensity histogram distribution parameter, 3D peak-to-valley height, and 3D surface waviness parameter are employed to indicate the onset of severe tool wear. In this work, aluminum (Al308) and compacted graphite iron parts were machined by a polycrystalline diamond insert and a multiphase coated tungsten carbide insert, respectively. After that, multiple 3D surface texture features of workpieces samples under different phases of tool wear were analyzed in order to assess tool wear conditions. The experimental results verify that these surface texture features can be used as good indicators for online tool wear monitoring.
Laser Shock Peening of Nanoparticles Integrated Alloys: Numerical Simulation and Experiments
Authors: Ye Chang , Cheng Gary J.
Published: December 2010

Nanocomposite and multiphase structures have become more important nowadays to enhance the mechanical properties of materials. Laser shock peening (LSP) is one of the most efficient ways to increase component fatigue life. In this paper, numerical and experimental studies have been carried out to study the effects of nanoparticles integrated structures during the laser shock peening of aluminum alloys. The LSP experiment of aluminum samples with different particle densities was carried out. The effect of nanoparticle on shock wave propagation, plastic deformation, energy absorption, and residual stress magnitude was studied. A qualitative agreement is found between experiment and simulation. The existence of nanoparticles affects the stress wave propagation and increases the ratio of absorbed energy to total energy and thus the magnitude of residual stress of the material after LSP.
Study of the Radioactive Liquid Waste Treatment by Coprecipitation: From Modeling to New Process Designs
Authors: Barre´ Yves , Pacary Vincent
Published: December 2010

The ever increasing pressure to reduce the release of radioactive and other toxic substances into environment requires constant improvement/upgrading of processes and technologies for treatment and conditioning of liquid radioactive wastes. To decontaminate liquid nuclear wastes, the coprecipitation process is the most commonly used in nuclear field because it can be applied to any type of aqueous effluents whatever their composition may be. This process deals with the in situ precipitation of solid particles to selectively remove one or more radioelements. In the nuclear research center of CEA (Commissariat a` l’Energie Atomique), the coprecipitation of 90Sr with barium sulphate is the technique used to treat selectively this radionuclide. In a previous study (1), an elaborated model is presented which predicts the radioactive strontium decontamination factor of nuclear waste solutions which can be achieved by using a coprecipitation process with barium sulphate. The originality of this new approach lies in the possibility to simulate the decontamination process in non equilibrium conditions and at the reactor scale. This modelling combined with the resolution of the population balance, enables to identify the influence of process parameters (flow rates, stirring speed…) on crystal size and ultimately on decontamination. Simulations of the strontium coprecipitation with barium sulphate have been performed in continuous and semi batch reactors. Thanks to these simulations, laws of the treatment efficiency variation as a function of several process parameters (mean residence time, stirring speed, BaSO4 concentration) have been determined and experimentally verified. This study leads to the determination of optimal treatment conditions. Three apparatus (recycling apparatus, fluidised bed and reactor/settling tank) providing these optimal conditions have been successfully tested and offered significant outlooks for the reduction of the residual sludge volume.
U.S. Department of Energy’s “Initiatives for Proliferation Prevention” Program: Solidification Technologies for Radioactive Waste Treatment in Russia
Authors: Pokhitonov Yuri , Kelley Dennis
Published: December 2010

Large amounts of liquid radioactive waste have existed in the U.S. and Russia since the 1950’s as a result of the Cold War. Comprehensive action to treat and dispose of waste products has been lacking due to insufficient funding, ineffective technologies or no proven technologies, low priority by governments among others. Today the U.S. and Russian governments seek new, more reliable methods to treat liquid waste, in particular the legacy waste streams. A primary objective of waste generators and regulators is to find economical and proven technologies that can provide long-term stability for repository storage. In 2001, the V.G. Khlopin Radium Institute (Khlopin), St. Petersburg, Russia, and Pacific Nuclear Solutions (PNS), Indianapolis, Indiana, began extensive research and test programs to determine the validity of polymer technology for the absorption and immobilization of standard and complex waste streams. Over 60 liquid compositions have been tested including extensive irradiation tests to verify polymer stability and possible degradation. With conclusive scientific evidence of the polymer’s effectiveness in treating liquid waste, both parties have decided to enter the Russian market and offer the solidification technology to nuclear sites for waste treatment and disposal. In conjunction with these efforts, the U.S. Department of Energy (DOE) will join Khlopin and PNS to explore opportunities for direct application of the polymers at predetermined sites and to conduct research for new product development. Under DOE’s “Initiatives for Proliferation Prevention” (IPP) program, funding will be provided to the Russian participants over a three year period to implement the program plan. This paper will present updated details of U.S. DOE’s IPP program, the project structure and its objectives both short and long-term, polymer tests and plications for LLW, ILW and HLW, and new product development initiatives.
Experience With Operation of Mobile Cementation Facility at A-1 NPP
Authors: Holicka Zuzana , Krajc Tibor , Kevicky Dusan , Urbanec Marian
Published: December 2010

The purpose of the paper is to describe a mobile cementation facility (MCF), which was designed by VUJE, Inc. and by JAVYS, Inc. (Nuclear and Decommissioning Company) in 2003. MCF was constructed and installed in 2004 in the so-called garden nearby A-1 NPP in Jaslovske Bohunice, where underground storage tanks for liquid radioactive waste are located. The facility is designed to process liquid radioactive waste and sludge or gravel collected from the underground tanks. These storage tanks are situated in the vicinity of active water treatment plant belonging to A-1 NPP. The tanks, some of which are of diameter 16 m, have their internal complex structure. All tanks were designed to collect various liquid waste streams from the A-1 NPP reactor building. Special remotely controlled DENAR 41 manipulator was developed. for the collection of liquid waste as well as for other purposes (collection of solid waste, decontamination, cutting of internal pipelines, etc.) The unique mobile equipment, which carries a suitable pump for sludge pumping to the cementation facility, was used to collect sludge last year. Large diameter of the storage tanks and small hatchways for the inspection access (approximately 540 × 540 mm) through which the telescopic mast of manipulator DENAR 41 or the special mobile vehicle were inserted into the tanks proved to pose some difficulties while being at use. Standard ISO containers, in which the main components are installed, were designed and used for the MCF project. The whole equipment is relatively easy to transport and can be installed to any other tanks with stored liquid waste. In-drum mixing technology is applied during cementation process. Standard 200 litre drums with the cement product are the only outputs form the mobile cementation facility. Production of 200 litre drums with the cemented product gradually increased from 19 pieces per year in 2005 to 88 pieces last year in 2008. Several problems particularly in the cement dosing system as well as problems in monitoring and measurement system with occasional failures in control system appeared amidst MCF operation. However these issues were always operatively resolved and the cementation facility could successfully met desired expectations.
External Disposal of 4 Steam Generators Out of the Decommissioning of the Nuclear Power Plant Stade (KKS)
Authors: Beverungen Martin
Published: December 2010

This paper describes the procedure for the qualification of large components (Steam Generators) as an IP-2 package, the ship transport abroad to Sweden and the external treatment of this components to disburden the Nuclear Power Plant from this task, to assure an accelerated the deconstruction phase and to minimize the amount of waste.
Challenges During the Decommissioning of the WAK Site: Dismantling of Highly Contaminated HLLW-Storage Tanks
Authors: Dux Joachim , Fath Oliver
Published: December 2010

The German pilot reprocessing plant WAK was shut down in 1990 after reprocessing about 200 Mg of nuclear fuels and is decided to be dismantled completely to the green field until year 2023. During the years 1994 until 2008 approximately 2.000 Mg of partly highly contaminated process equipment and 1.500 Mg of concrete structures corresponding to 99% of the radioactive inventory of 5E14 Bq of the WAK reprocessing building have already been dismantled. A major prerequisite for the complete dismantling of the WAK is the management of the 60 m3 high-level liquid waste (HLLW) with a total β/γ-activity of 8.0E17 Bq resulting from reprocessing. For this purpose the Karlsruhe Vitrification Plant (VEK) was constructed in the years between 2000 and 2005 and inactively tested in 2007. The subsequent nuclear test operation and routine hot operation of the VEK plant are planned to start mid-2009. In parallel to vitrification operation, dismantling of the four HLLW tanks in the storage buildings will be prepared for remote dismantling.
Characterization of Cadmium-Resistant Bacteria and Their Application for Cadmium Bioremediation
Authors: Siripornadulsil Surasak , Siripornadulsil Wilailak
Published: December 2010

On a global basis, trace-metal pollution is one of the most pervasive environmental problems. It is particularly difficult to prevent or clean up because the metals are toxic in their elemental form and cannot be decomposed. Bioremediation has been shown to be a powerful system for heavy metal pollution clean up and prevention. In this work, we characterized the cadmium (Cd)-resistant bacteria isolated from rice field soil downstream from zinc (Zn) mineralized area which the owners were contaminated at high level of cadmium content in their blood (>10 μgCd/g creatinine). We found that all 24 isolated bacteria tolerated toxic Cd concentrations (2,500 μM). In order to determine whether the Cd toxicity affected the growth of isolated bacteria, we grew the isolated bacterial cells in the absence and presence of toxic concentrations of CdCl2 (500 μM). In the absence of Cd, all isolated bacterial cells grew slightly better than in the presence of toxic concentrations of Cd. In addition, the Cd binding capacity of all isolated bacteria were very high, ranging from 6.38 to 9.38 log[Cd(atom)]/cell when grown in the presence of 500 μM CdCl2. Furthermore, the stability of Cd-bacteria complex of all isolated bacteria was affected by 1mM EDTA. When grown in the presence of 500 μM CdCl2, Cd-resistant isolates S2500-6, -8, -9, -15, -17, -18, -19, and -22 increasingly produced proteins containing cysteine (SH-group) (from 1.3 to 2.2 times) as well as 11 isolates of Cd-resistant bacteria, including S2500-1, -2, -3, -5, -6, -8, -9, -11, -16, -20, and -21, increasingly produced inorganic sulfide (1.5 to 4.7 times). Furthermore, the Sulfur K-edge X-ray absorption near-edge structure (XANES) spectroscopy studies indicated that Cd-resistant isolated S2500-3 precipitated amounts of cadmium sulfide (CdS), when grown in the presence of 500 μM CdCl2. The results suggested that these Cd-resistant bacteria have potential ability to precipitate a toxic soluble CdCl2 as nontoxic insoluble CdS. Interestingly, Cd-resistant bacteria isolated S2500-3, -8, -9,and -20 increased cadmium tolerance of Thai jasmine rice (Kao Hom Mali 105) when grown in the presence of 200 μM CdCl2. These 4 isolates also decreased cadmium concentration accumulation in Kao Hom Mali 105 plant at 61, 9, 6, and 17%, respectively when grown in the presence of 200 μM CdCl2. They were identified by 16S rDNA sequence analysis and classified as Cupriavidus taiwanensis (isolate S2500-3) and Pseudomonas aeruginosa (isolates S2500-8, -9, and -20).
Independent Monitoring of Radiological Impact at Decommissioned NPP A1 Site
Authors: Slavik Ondrej , Listjak Martin , Slaninka Alojz , Moravek Jozef , Soos Frantisek , Dulanska Sylvia
Published: December 2010

Monitoring of characteristics of the radiation situation in close surrounding of the decommissioned NPP A1 by an independent organization is described and discussed in the paper. The measurements are carried out in the NPP A1 site close to the VUJE operation building, not far from the places, where the decommissioning activities are concentrated. These activities relate to bringing the NPP A1 to safer conditions, e.g. cleanup of contaminated underground waste water reservoirs, solidification of the removed sludge from these reservoirs by an in situ open air solidification system, cleaning of contaminated concretes and so on. Other activities also relate to radiological impact to the environment, e.g. radioactive waste processing at Bohunice RW -Ttreatment Centre and intensive traffic of sources of ionising radiation to and from this centre located very close to the place mentioned above. Results of the measurements carried out by VUJE accredited laboratory in the frame of Decommissioning project of NPP A1 present an uninterrupted time series of measurements and enable evaluation of development for the last 17 years. The monitoring results demonstrate that the only significant radionuclide indicating radiological impact of the decommissioning is 137Cs. Its activity concentration in atmospheric aerosols at the sampling point has been time to time elevated and in average is by about one order higher in comparison with a 100 km far reference (background) site.
Designing a New Highly Active Liquid Evaporator
Authors: Robson Paul , Candy Emma
Published: December 2010

The Highly Active Liquid Effluent Storage (HALES) plant stores, concentrates and conditions Highly Active Liquor (HAL) in evaporators for buffer storage in Highly Active Storage Tanks (HAST). Highly Active (HA) evaporators play a pivotal role in the delivery of reprocessing, historic clean up and hazard reduction missions across the Sellafield site. In addition to the engineering projects implemented to extend the life expectation of the current evaporator fleet, the UK Nuclear Decommissioning Agency (NDA) is sponsoring the construction of a new HA evaporator (Evaporator D) on the Sellafield site. The design and operation of the new HA evaporator is based on existing/recent HA evaporator technology but learning from past operational experience. Operational experience has been a key area where the existing plant operators have influenced both the new design itself and the requirements for commissioning and training. Many of the learning experiences require relatively simple engineering design modifications such as a new internal washing provision and transfer line blockage recovery systems, they are never-the-less expected to significantly improve the flexibility and operational capability of the new evaporator. Issues that the project delivery team has addressed as part of the development of the design and construction have included: • Minimising interruptions and/or changes to the normal operations of interfacing plants during construction, commissioning and operation of the new facility. • Modularisation of the plant, enabling fabrication of the majority of the plant equipment off-site within a workshop (as opposed to on-site) environment improving Quality Assurance and reducing on-Site testing needs. • Drawing out the balance between operational and corrosion resistance improvements with actual design and delivery needs. • Provision of a new facility reliant on the infrastructure of an existing and ageing facility and the competing demands of the related safety cases.
The Level of Uncertainty in Materials Clearance
Authors: Burgess Peter
Published: December 2010

Measurement of surface levels is essential in waste assessment and in clearing materials from nuclear licensed sites. Radiation measurements in general are much less accurate than most forms of engineering measurement, even in relatively simple conditions, such as radiochemical laboratories. Waste assessment during clearance is far more difficult. The areas of uncertainty include: (1) The intrinsic limitations of the equipment employed. For surface activity measurement, the detector is often a large area alpha + beta scintillation probe connected to a ratemeter. Any detector has an effective energy threshold below which it fails to register an event. The detector response is rarely uniform over the window area. The detector is connected to a ratemeter. The design of a ratemeter and the way it is set up will have a large influence on how easy the user finds it to classify correctly materials close to the exempt limit. (2)Calibration of the equipment. There is only a limited set of surface contamination sources available. Prediction of the response to other nuclides can be complicated. (3)Determination of the fingerprint. For many practical situations, the potential contaminant is a mixture of nuclides emitting a mixture of alpha, beta, gamma and X radiation. Any detector will have a response which depends on the radiation type and energy. Frequently, the response to the fingerprint of the most operationally robust and convenient detectors will be dominated by only a small fraction of the total activity present. It is thus vital that that fraction is well established and any area zoned so that the fraction remains reasonably stable. (4)The influence of natural activity in materials and of gamma radiation from elsewhere. Many building materials have levels of natural activity in the Bq/g region. These often vary significantly from sample to sample and area to area, particularly where buildings and equipment have been extended or modified. (5)Surface condition. For short range emissions such as alpha particles and low energy betas, the range for detection in air is a few mm. Any material covering the activity, such as paint or grease, will reduce the emission rate.
Evaluation and Potential Remediation of the Industrial Norm Legacy in Liverpool
Authors: Reeves Nigel , John Gordon H. , Major Bob
Published: December 2010

Sefton, on the north side of Liverpool, holds a radioactive legacy from its industrial past. This legacy is in the form of Tin slag buried in sub-surface seams. Located near the docks and adjacent to the rich Lancashire coal seams, Sefton became one of the main production centres of Tin plate in Britain. A consequence of this industrial process is the production of mildly radioactive waste slag. Tin rich ores are heated under reducing conditions to produce a molten metal stream This is then separated into the component metal streams. Solid wastes produced by this process are known as slag and were usually stored on site in spoil heaps. Because this slag is a very hard, glassy material it has been historically used as aggregate in underlying roads and rail way sleepers. Many of these sites pre-date the introduction of the regulation of radioactive substances in the UK and have never been under legislative control under the Radioactive Substances Act, RSA93. There is a risk that the existence may not be known of some of these sites. U-238 and Th-232 and their associated decay chains, are the major contributors to the radionuclide inventory of the slags, levels of these radionuclides being in the range 1–10Bq/g. A series of alpha and beta decays for both chains leads eventually to the generation of a stable isotope of lead. Radiologically, the main area of concern is with the potential inhalation or ingestion of contaminated dusts. There is also a potential for Ra-226 to leach out into groundwater. AMEC has worked for Sefton Metropolitan Council and various developers, to carry out specialist, non intrusive gamma radiation surveys of numerous sites in Sefton. This is the first stage in carrying out a radiological risk review of a given site. What often then follows is an intrusive, geo-technical survey, with trial pitting and radiological sampling for later sensitive lab based radiochemical analysis. Radiological supervision is also required at this time to ensure that the radiological exposure of the Contractors carrying the survey is restricted and ensure that plant dose not become contaminated with radionuclides. These surveys are the preliminary stage for redevelopment works with new housing replacing antiquated commercial premises. By bringing together expertise in sensitive gamma surveying, radiochemical analysis and a detailed understanding of the regulatory framework, AMEC is able to support the borough of Sefton in its re-development programme ensuring safe compliant development of an area with an historic radiological legacy.
PET Cyclotron Design for Decommissioning and Waste Inventory Reduction
Authors: Major Bob
Published: December 2010

In this paper we will examine the decommissioning and radioactive waste implications of a hypothetical cyclotron facility. from conception through design into operation and finally decommissioning. Supported by the computer codes MCNPX, MCNP and FISPACT we illustrate the induced activity in the cyclotron pit walls. Using the computer codes it is possible to highlight the problems associated with neutron activation of the cyclotron pit walls and the need for specialist shielding materials, such as boronated polyethylene. Using MCNP it is possible to design a vault for cost effective decommissioning through the use of sacrificial layers. This code allows the likely degree of activation and penetration of activation products to be quantified and hence gives an idea of waste disposal costs. In summary, a dedicated PET facility will challenge most RPAs. A wide range of skills are needed which encompass practical operational procedures, through specialist shielding design using Monte Carlo codes to the ability to appear confident to Regulators who may be finding the experience the same steep learning curve.
Control of Materials Harmful to Water in the German KONRAD Repository
Authors: Kugel Karin , Brennecke Peter , Steyer Stephan , Gruendler Detlef , Boetsch Wilma , Haider Claudia
Published: December 2010

In order to avoid a pollution of the near surface ground water during the post closure phase of the Konrad repository the acceptable amount of material harmful to water in the radioactive waste is restricted. For this purpose the KONRAD plan approval order includes waste requirements referring to the German water law (“water law permission”). In a first part of this contribution the water law permission for the KONRAD repository is introduced. This permission contains a list of materials harmful to water with the respective limitations in mass and many instructions and proposals regarding the registering and balancing of these materials as well as quality assurance aspects. The second part deals with the implementation of the water law permission in the waste acceptance criteria. The waste producer has to describe his waste in a standardized way with respect to the material composition. The operator of the repository has to check this description and to register and balance the materials and substances harmful to water. This procedure is based on a standardized list of materials and a list of containers. In the third part quality control measures used for the proof of the compliance with the acceptance criteria (with respect to the water law permission) are described. In particular objective of the quality control, possible quality control options and acceptable margins are dealt with.
Separation of Lanthanide Fission Products in a Eutectic Waste Salts Delivered From Pyroprocessing of a Spent Oxide Fuel by Using Lab-Scale Oxidative Precipitation Apparatus
Authors: Cho Yung-Zun , Kim In-Tae , Yang Hee-Chul , Park Hwan-Seo , Lee Han-Soo
Published: December 2010

Co-precipitation experiments of lanthanides were carried out using this lab-scale apparatus (4kg-salt/batch). As lanthanides, 8 lanthanide elements (Y, La, Ce, Pr, Nd, Sm, Eu and Gd) were used. By reaction with oxygen, these 8 lanthanide chlorides were converted their oxide (REO2, RE2O3) or oxychloride form. Since these lanthanide oxides or oxychlorides are nearly molten salt insoluble, they all were precipitated by free settling in the bottom of molten salt bed, where about 7–8 hrs precipitation time was requested. It was found that in the conditions of 700 °C - 12 hours sparging time and 5 L/min, all the used lanthanide elements showed over 99.5% oxidation efficiency. But in case of 800 °C molten salt temperature only after 7 hours they showed over 99% oxidation efficiency.
The Government of Canada’s Programs for Radioactive Waste Cleanup and Long-Term Management
Authors: McCauley Dave , Metcalfe Douglas , Blanchette Marcia , Calvert Tom
Published: December 2010

The Government of Canada’s 1996 Policy Framework for Radioactive Waste Management establishes that waste owners are responsible for the management of their radioactive wastes. This includes the planning, funding, and implementation of long-term waste management initiatives. Within this context, the Government has established three separate programs aimed at addressing the long-term management of radioactive waste for which it has accepted responsibility. The largest of these programs is the Nuclear Legacy Liabilities Program (NLLP). The objective of the NLLP is to address radioactive waste and decommissioning liabilities resulting from 60 years of nuclear research and development at Atomic Energy of Canada Limited (AECL) sites in Canada. In 2005, the Government increased the value of this liability in its Public Accounts based on a new, 70-year long-term strategy and, in 2006, it implemented a $520 million 5-year work plan to initiate the strategy. The cost of implementing the full strategy is estimated at about $7 billion (current-day dollars). Canada’s Historic Waste Program is a second program that is designed to address low-level radioactive wastes across Canada that are not managed in an appropriate manner for the long-term and for which the current owner can not reasonably be held responsible. These wastes mainly emanate from the refining and use of radium in the 1930s and the very early days of the nuclear industry in Canada when radioactive ores were mined and transported long distances for processing. While the Historic Waste Program has been in place since 1982, the Government of Canada launched the Port Hope Area Initiative in 2001 to deal with the bulk of the waste. Finally, the Government of Canada has entered into two agreements with Canadian provincial governments on roles and responsibilities relating to the decommissioning of uranium mine and mill tailings sites. These agreements, one with the Province of Ontario and one with the Province of Saskatchewan, establish the responsibilities of each level of government to address circumstances where further decommissioning work is required and the producer can no longer be held responsible. The paper will provide an overview of these environmental remediation programs for radioactive waste and will describe recent progress and future challenges.
Remote Measurements of Radioactivity Distribution With BROKK Robotic System
Authors: Ivanov Oleg , Danilovich Alexey , Stepanov Vyacheslav , Smirnov Sergey , Potapov Victor
Published: December 2010

Robotic system for the remote measurement of radioactivity in the reactor areas was developed. The BROKK robotic system replaces hand-held radiation measuring tools. The system consists of a collimated gamma detector, a standard gamma detector, color CCD video camera and searchlights, all mounted on a robotic platform (BROKK). The signals from the detectors are coupled with the video signals and are transferred to an operator’s console via a radio channel or a cable. Operator works at a safe position. The video image of the object with imposed exposure dose rate from the detectors generates an image on the monitor screen, and the images are recorded for subsequent analysis. Preliminary work has started for the decommissioning of a research reactor at the RRC «Kurchatov Institute». Results of the remote radioactivity measurements with new system during radiation inspection waste storage of this reactor are presented and discussed.
Applying Best Practical Environmental Optioneering (BPEO) to a Complex Clean Up Programme: A Ponds and Silos Case Study
Authors: Candy Simon
Published: December 2010

The use of Best Practical Environmental Optioneering (BPEO) has long been part of informed decision making within the Nuclear Industry. However, BPEO has typically been applied to specific and discrete objectives, for example the selection of a technology to treat a particular nuclear waste stream. While this has sometimes been extended to cover a number of objectives, no one had applied BPEO to a programme of the size and complexity of that associated with Legacy Ponds & Silos at Sellafield. The programme, spanning more than 30 years, includes a range of different objectives covering ongoing management, recovery, conditioning, storage and ultimately disposal of nuclear wastes. This range of activities is applied across a number of facilities containing multiple, significant waste streams. This paper explains how BPEO was applied to the Legacy Ponds & Silos programme and discussed some of the learning resulting from that exercise.
Monte Carlo Simulation of a Compartment Model of Radionuclide Migration at a Radioactive Waste Repository
Authors: Cadini Francesco , De Sanctis Jacopo , Zio Enrico , Avram Diana , Girotti Tommaso , Luce Alfredo , Taglioni Alberto
Published: December 2010

Prediction of radionuclides release is a central issue in the performance assessment of nuclear waste repositories. To this aim a model of radionuclides migration through the repository barriers must be set up, accounting for the uncertainties affecting the process. In this context, the present paper presents the application of Monte Carlo simulation to a Markovian modeling framework proposed in the literature; two cases are presented to highlight the value added by the flexibility of the Monte Carlo simulation approach.
European Radiation Survey and Site Execution Manual (EURSSEM)
Authors: van Velzen Leo , Teunckens L. , Daniska V. , Vasko M. , Hajkova E. , Matejovic I.
Published: December 2010

Within the framework of the “Co-ordination Network on Decommissioning of Nuclear Installations Project (2005–2008)” funded by the European Community a first edition of EURSSEM has been developed to promote common understanding of key issues in the development of a strategy, implementation and execution of a programme to remediate radioactively contaminated sites. The objective of EURSSEM is to describe and provide a consistent consensus information and guidance on strategy, planning, implementation and execution of stakeholder involvement, performing, and assessing radiological soil surface and groundwater (final) status surveys to meet established dose- or risk-based release criteria, and/or remediation, restoration, reuse and stewardship objectives, while at the same time encouraging effective use of human, raw material and financial resources. To be able to provide a consistent guidance and leading practices to involved participants (stakeholders) in a remediation programme for radioactively contaminated sites, an extensive literature study has been performed to collect important documents that have been produced in this field by the International Atomic Energy Agency (IAEA), the SAFEGROUNDS Learning Network, Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) and other national and international institutes. EURSSEM incorporates information provided in those and other documents to conduct all actions at radioactively contaminated and potentially radioactively contaminated sites and/or groundwater up to their release for restricted or unrestricted (re)use. Brief descriptions are provided about the background and the need for a document like EURSSEM, about key issues like stakeholder involvement and archiving for future referencing including the follow-up of the further development of EURSSEM.
Experiences in Teaching Decommissioning
Authors: Catlow Fred
Published: December 2010

The paper describes the experience gained by the author in teaching decommissioning in the Highlands of Scotland. Initially when asked to teach the subject of decommissioning to students sitting for a BSc degree in “Electrical or Mechanical Engineering with Decommissioning Studies”, the author was taken aback, not having previously taught degree students and there was no precedent since there was no previous material or examples to build on. It was just as difficult for the students since whilst some had progressed from completing HND studies, the majority were employed at the Dounreay site and were mature students with families who were availing themselves of the opportunity for career advancement (CPD). Some of the students were from the UKAEA and its contractors whilst others were from Rolls-Royce working at Vulcan, the Royal Navy’s establishment for testing nuclear reactors for submarines. A number of the students had not been in a formal learning environment for many years. The College which had originally been funded by the UKAEA and the nuclear industry in the 1950’s was anxious to break into the new field of Decommissioning and were keen to promote these courses in order to support the work progressing on site. Many families in Thurso, and in Caithness, have a long tradition of working in the nuclear industry and it was thought at the time that expertise in nuclear decommissioning could be developed and indeed exported elsewhere. In addition the courses being promoted by the College would attract students from other parts so that a centre of excellence could be established. In parallel with formal teaching, online courses were also developed to extend the reach of the College. The material was developed as a mixture of power point presentations and formal notes and was obtained from existing literature, web searches and interactive discussions with people in the industry as well as case studies obtained from actual situations. Assignments were set and examination papers prepared which were validated by internal and external assessors. The first course was started in 2004 (believed to be unique at that time) and attracted eight students. Subsequent courses have been promoted as well as a BEng (Hons) course which also included a course on Safety and Reliability.