Comparison of concepts for independent spent fuel storage facilities

International Nuclear Information System (INIS)

Held, Ch.; Hintermayer, H.P.

1978-01-01

The design and the construction costs of independent spent fuel storage facilities show significant differences, reflecting the fuel receiving rate (during the lifetime of the power plant or within a very short period), the individual national policies and the design requirements in those countries. Major incremental construction expenditures for storage facilities originate from the capacity and the type of the facilities (casks or buildings), the method of fuel cooling (water or air), from the different design of buildings, the redundancy of equipment, an elaborate quality assurance program, and a single or multipurpose design (i.e. interim or long-term storage of spent fuel, interim storage of high level waste after fuel storage). The specific costs of different designs vary by a factor of 30 to 60 which might in the high case increase the nuclear generating costs remarkably. The paper also discusses the effect of spent fuel storage on fuel cycle alternatives with reprocessing or disposal of spent fuel. (author)

Burnup credit implementation in WWER spent fuel management systems: Status and future aspects

International Nuclear Information System (INIS)

Manolova, M.

1998-01-01

This paper describes the motivation for possible burnup credit implementation in WWER spent fuel management systems in Bulgaria. The activities being done are described, namely: the development and verification of a 3D few-group diffusion burnup model; the application of the KORIGEN code for evaluation of WWER fuel nuclear inventory during reactor core lifetime and after spent fuel discharge; using the SCALE modular system (PC Version 4.1) for criticality safety analyses of spent fuel storage facilities. Future plans involving such important tasks as validation and verification of computer systems and libraries for WWER burnup credit analysis are shown. (author)

Overweight according to geographical origin and time spent in France: a cross sectional study in the Paris metropolitan area

Directory of Open Access Journals (Sweden)

Martin-Fernandez Judith

2012-10-01

Full Text Available Abstract Background For the first time in France in a population-based survey, this study sought to investigate the potential impact of migration origin and the proportion of lifetime spent in mainland France on body mass index (BMI and overweight in adults living in the Paris metropolitan area. Methods A representative, population-based, random sample of the adult, French speaking population of the Paris metropolitan area was interviewed in 2005. Self-reported BMI (BMI = weight/height2 and overweight (BMI ≥ 25 were our 2 outcomes of interest. Two variables were constructed to estimate individuals’ migration origin: parental nationality and the proportion of lifetime spent in mainland France, as declared by the participants. We performed multilevel regression models among different gender and age groups, adjusted for demographics and socioeconomic status. Results In women, a parental origin in the Middle East or North Africa (MENA was associated with a higher risk of being overweight (especially before the age of 55 and a higher BMI (between 35 and 54 years of age, and so were women of Sub-Sahara African parental origin in the middle age category. Only in the youngest men ( Conclusions Our results plea for potential cultural determinants of overweight in the migrant and migrants-born populations in the French context of the capital region. Taking into account the people’ family and personal migration histories may be an important issue in public health research and policies on overweight and obesity prevention.

Positron lifetime studies on thorium oxide powders

International Nuclear Information System (INIS)

Upadhyaya, D.D.; Muraleedharan, R.V.; Sharma, B.D.

1982-01-01

Positron lifetime spectra have been studied for ThO 2 powders, calcined at different temperatures and having different particle sizes. Three lifetime components could be resolved, the longest component being of low intensity. An observed strong dependence on the particle size of the annihilation process and the variation of positronium diffusion constant is explained on the basis of defect density variations in these powders. (author)

Spent fuel management in South Africa

International Nuclear Information System (INIS)

Bredell, P.J.; Stott, A.K.

1998-01-01

Eskom, the South African utility, operates one of the largest electricity networks in the world. However, only 6% of the South African generating capacity is nuclear; the remainder is coal fired and hydroelectric. The nuclear component consists of the Koeberg Nuclear Power Plant, comprising two French supplied PWRs of 920 MWe each, situated approximately 45 kilometres from cape Town. Construction started in 1976 and the two reactors reached criticality in 1984 and 1985 respectively. South Africa also has an Oak Ridge type research reactor, called SAFARI, operated by the South African Atomic Energy Corporation (AEC) at their Pelindaba site near Pretoria. This research reactor was commissioned in 1965, and has been in operation ever since. South Africa has a National Radioactive Waste Disposal facility called Vaalputs, some 600 km north of Cape Town. The facility, operated by AEC, is presently licensed only for the disposal of low and intermediate radioactive level wastes. Vaalputs offers unique features as a potential interim spent fuel storage and final disposal site, such as favorable geology (granite), low seismicity, low population density, remoteness from industrial centres and and conditions. Therefore, this site has been investigated by the AEC as a potential interim spent fuel storage site, but has not yet been licensed for this purpose. Hence, all spent fuel is currently stored on the two sites at Koeberg and Pelindaba respectively. The spent fuel storage pools at Koeberg have recently been enlarged to accommodate the lifetime spent fuel arisings of the plant. Since late 1997, the Safari spent fuel is stored in a pipe storage facility, constructed away from the reactor on the Pelindaba site. (author)

Long Term Management of Spent Fuel from NEK

International Nuclear Information System (INIS)

Kegel, L.; Zeleznik, N.; Lokner, V.

2012-01-01

In 2008 Slovenian national agency for radioactive waste management ARAO started together with Croatian sister organization APO elaboration of a new revision of Decommissioning, Radioactive waste and Spent fuel management program for NPP Krsko. In scope of this work also new studies for spent fuel storage and disposal were prepared in which technical solutions were analyzed and proposed for specific spent fuel (SF) from NPP Krsko. Time schedules for main activities of SF disposal development were elaborated for two alternative scenarios which correspond to normal NPP Krsko operation and 20 - year lifetime extension. All technical activities were financially assessed and costs estimates of SF storage and geological disposal development provided. The prepared studies were verified by international experts in order to confirm the correctness of technical inputs, proposed solutions, time schedules of activities and costs evaluations. The calculated nominal and discounted costs of spent fuel management served for the recalculation of annuities in the integral scenarios of interrelated activities on NPP Krsko decommissioning, LILW and SF management. Besides new first proposal of long-term management of spent fuel from NPP Krsko the joint work also opened additional questions. One of this is time schedule of proposed activities for long term SF management - what were the criteria used in the determination of actions and are they optimal for both countries. How the process of site selection for SF storage or disposal should be prepared having in mind that it will bring many questions in both countries? Is direct disposal of SF still the best solution in current development of nuclear prospects? The paper will present the current development and solutions for SF management from NPP Krsko and will try to answer questions which need to be solved and future development in the SF management.(author).

Positron lifetime studies of electron irradiated copper

International Nuclear Information System (INIS)

Hadnagy, T.D.

1976-01-01

Single-crystal copper was irradiated with 4.5-MeV electrons producing simple Frenkel defects as well as a significant concentration of divacancies. Mean positron lifetime characteristics, which are sensitive to the presence of vacancies and multivacancies in copper, was monitored after isochronal anneals between 80 and 800 0 K to determine the relative change of characteristic mean lifetimes and their associated intensities. Also a study of the dependence of the mean positron lifetime on the total electron fluence was made and compared with existing theories relating these lifetimes to vacancy or multivacancy concentrations. Numerical data from curve fitting procedures using a conventional trapping model for defect-induced changes in positron lifetimes indicate that upon irradiation with 4.5-MeV electrons at 80 0 K, about 8 percent of the defects produced are divacancy units. Divacancy units appear to be several times more effective in trapping positrons than are monovacancies. Further, the experimental data suggest that the stage III annealing processes in electron-irradiated copper most probably involve the motion and removal of both monovacancies and divacancies. A conglomerate (multivacancy) unit appears to exist as a stable entity even after annealing procedures are carried out at temperatures slightly above the stage III region. Such a stable unit could serve as a nucleation center for the appearance of voids

A cost-benefit analysis of spent fuel management

International Nuclear Information System (INIS)

Lamorlette, G.

2001-01-01

The back end of the fuel cycle is an area of economic risk for utilities having nuclear power plants to generate electricity. A cost-benefit analysis is a method by which utilities can evaluate advantages and drawbacks of alternative back end fuel cycle strategies. The present paper analyzes how spent fuel management can influence the risks and costs incurred by a utility over the lifetime of its power plants and recommends a recycling strategy. (author)

Study of variables for accelerating lifetime testing of SOFCs

DEFF Research Database (Denmark)

Ploner, Alexandra; Hagen, Anke; Hauch, Anne

Solid oxide fuel cell (SOFC) applications require lifetimes of several years on the system level. A big challenge is to proof/confirm/demonstrate such exceptionally long lifetimes.Accelerated or compressed testing are possible methods. Activities in this area have been carried out without arriving...... at different current load cycling profiles revealed a strong deviation between predicted and measured lifetime [3].In this study, we present a detailed analysis of durability results for degradation mechanisms of single SOFC components as function of operating conditions. Electrochemical impedance data...

Re-racking the spent fuel pit in nuclear power plant Krsko

International Nuclear Information System (INIS)

Volaric, B.; Krajnc, B.

2003-01-01

Krsko NPP was designed to temporary store a limited number of spent fuel assemblies (SFA). They were planned to be either removed for reprocessing or permanently stored. By the design the plant would run out of capacity for temporary storing of SFAs in 2003. This means that the plant could not operate further without additional changes since valid regulations require the Spent Fuel Pit (SFP) free storage capacity for the whole emergency core unloading (ECU). The purpose of the SFP Reracking Project is to assure a safe storage of all SFAs in the existing SFP during the plant lifetime. Design solutions and related analysis did not only consider the quantity of spent fuel for the plant lifetime, i.e. up to the year 2023, but also a possibility of the SFP extension for eventually extended plant lifetime of 20 years. According to the project, racks were designed to provide up to 1694 cells for storage of FAs in Phase I which is sufficient for normal NPP operation up to its lifetime, i.e. the year 2023. The extension of temporary storage capacity of SFAs in the SFP was made by a combination of existing and new high-density racks. Three modules from the existing 12 were eliminated. Thus leaving 621 cells. There are nine new racks added with up to 1073 supercompacted cells installed in the empty part of the pool. The spacing between new cells is smaller than the one between existing cells because of special plates, made of borated stainless steel. The design of the racks fulfils all the applicable requirements to ensure sub-criticality of all stored SFAs, enriched up to 5 % U 235 with peak pellet burnup above 40 GWD/MTU. Besides static and dynamic seismic loading of both, the racks and the fuel handling building, sufficient cooling of FAs is provided as well as accident conditions precluded. Greater cooling capacity is achieved by installing the third heat exchanger, connected in parallel to existing two exchangers. The design and manufacturing of the new heat exchanger

Studies and research concerning BNFP. Nuclear spent fuel transportation studies

International Nuclear Information System (INIS)

Anderson, R.T.; Maier, J.B.

1979-11-01

Currently, there are a number of institutional problems associated with the shipment of spent fuel assemblies from commercial nuclear power plants: new and conflicting regulations, embargoing of certain routes, imposition of transport safeguards, physical security in-transit, and a lack of definition of when and where the fuel will be moved. This report presents a summary of these types and kinds of problems. It represents the results of evaluations performed relative to fuel receipt at the Barnwell Nuclear Fuel Plant. Case studies were made which address existing reactor sites with near-term spent fuel transportation needs. Shipment by either highway, rail, water, or intermodal water-rail was considered. The report identifies the impact of new regulations and uncertainty caused by indeterminate regulatory policy and lack of action on spent fuel acceptance and storage. This stagnant situation has made it impossible for industry to determine realistic transportation scenarios for business planning and financial risk analysis. A current lack of private investment in nuclear transportation equipment is expected to further prolong the problems associated with nuclear spent fuel and waste disposition. These problems are expected to intensify in the 1980's and in certain cases will make continuing reactor plant operation difficult or impossible

A study of lifetime within the -12 sec range

International Nuclear Information System (INIS)

Dorobantu, V.

1977-01-01

Lifetimes of excited nuclear states are studied with a particular emphasis on the determination of nuclear lifetimes by means of the Doppler shift decomposition attenuation method - DSAM - which is based on the mathematical theory of stochastic processes; by its own nature, the emission of recoil nuclei, their motion through an amorphous medium and the detection of gamma rays resulting from these nuclei are all stochastic processes as well. Measurements of lifetimes together with other measurements can supply nuclear structure data, as well as information on the slowing-down process of an energetic ion through a certain material. The experimental tests have been carried out on the Tandem accelerator - IFIN, Bucharest. (author)

The preliminary design and feasibility study of the spent fuel and high level waste repository in the Czech Republic

International Nuclear Information System (INIS)

Valvoda, Z.; Holub, J.; Kucerka, M.

1996-01-01

In the year 1993, began the Program of Development of the Spent Fuel and High Level Waste Repository in the Conditions of the Czech Republic. During the first phase, the basic concept and structure of the Program has been developed, and the basic design criteria and requirements were prepared. In the conditions of the Czech Republic, only an underground repository in deep geological formation is acceptable. Expected depth is between 500 to 1000 meters and as host rock will be granites. A preliminary variant design study was realized in 1994, that analyzed the radioactive waste and spent fuel flow from NPPs to the repository, various possibilities of transportation in accordance to the various concepts of spent fuel conditioning and transportation to the underground structures. Conditioning and encapsulation of spent fuel and/or radioactive waste is proposed on the repository site. Underground disposal structures are proposed at one underground floor. The repository will have reserve capacity for radioactive waste from NPPs decommissioning and for waste non acceptable to other repositories. Vertical disposal of unshielded canisters in boreholes and/or horizontal disposal of shielded canisters is studied. As the base term of the start up of the repository operation, the year 2035 has been established. From this date, a preliminary time schedule of the Project has been developed. A method of calculating leveled and discounted costs within the repository lifetime, for each of selected 5 variants, was used for economic calculations. Preliminary expected parametric costs of the repository are about 0,1 Kc ($0.004) per MWh, produced in the Czech NPPs. In 1995, the design and feasibility study has gone in more details to the technical concept of repository construction and proposed technologies, as well as to the operational phase of the repository. Paper will describe results of the 1995 design work and will present the program of the repository development in next period

On Developments in the Mean Joint Lifetimes of Three- and Four-Generation Families in Western and Eastern Germany – A model Calculation

Directory of Open Access Journals (Sweden)

Evelyn Grünheid

2011-01-01

Full Text Available This article tackles the question of how, on the one hand, the high life expectancy and, on the other, the increasing age of mothers at childbirth will impact the joint lifetime of three and four generations and will develop in future. To this end, indicators are derived from the official data on mortality and fertility for the mean joint lifetimes of three- and four-generation families. Because of the complicated data available, the investigation will be restricted to the female succession of generations, and here to an observation of the first-born child in each case. The indicators act as model calculations, which is why they serve above all to indicate (future developments in mean joint lifetimes. The indicators are calculated for the average jointly-spent lifetime of three-generation families for the period from 1990 to 2060, and of four-generation families for the period from 2010 to 2060. The result of the calculations for Western Germany show an increase in the jointly-spent lifetime of three generations of up to roughly 35 years in 2000, after which that the figure falls continually to a value of roughly 30 years. A similarly developing trend emerges for four generations, but this is delayed by roughly 30 years towards the future, and reaches the highest value around 2030 to 2040, at roughly seven to ten years. For Eastern Germany, with its even younger age of women at childbirth in both the past and in the present, the maximum jointly-spent life years of three generations at the beginning of the observation period (roughly around 1990 is almost 40 years, after which this indicator falls continuously. The indicator of the average jointly-spent years of four-generation families, by contrast, probably reaches a maximum around 2020, with a value of 12 to 14 years. Also after this, one may anticipate a reduction in the joint lifetimes of four-generation families in Eastern Germany. All in all, the trends of the indicators denote that one

Final disposal of spent fuel in the Finnish bedrock

International Nuclear Information System (INIS)

1992-12-01

Teollisuuden Voima Oy (TVO) is preparing for the final disposal of spent nuclear fuel from the Olkiluoto nuclear power plant (TVO-I and TVO-II reactors). According to present estimates, a total of 1840 tU of spent fuel will be accumulated during the 40-year lifetime of the power plant. An interim storage facility for spent fuel (TVO-KPA Store) has operated at Olkiluoto since 1987. The spent fuel will be held in storage for several decades before it is shipped to the repository site. Both train and road transportation are possible. The spent fuel will be encapsulated in composite copper and steel canisters (ACP Canister) in a facility that will be build above the ground on the site where the repository is located. The repository will be constructed at the depth of several hundreds of meters in the bedrock. In 1987 five areas were selected for preliminary site investigations. The safety analysis (TVO-92) that was carried out shows that the proposed safety criteria would be met at each of the candidate sites. In future expected conditions there would never be significant releases of radioactive substances to the biosphere. The site investigations will be continued in the period 1993 to 2000. In parallel, a R and D programme will be devoted to the safety and technology of final disposal. The site for final disposal will be selected in the year 2000 with the aim of having the capability to start the disposal operations in 2020

Preliminary study on direct recycling of spent PWR fuel in PWR system

International Nuclear Information System (INIS)

Waris, Abdul; Nuha; Novitriana; Kurniadi, Rizal; Su'ud, Zaki

2012-01-01

Preliminary study on direct recycling of PWR spent fuel to support SUPEL (Straight Utilization of sPEnt LWR fuel in LWR system) scenario has been conducted. Several spent PWR fuel compositions in loaded PWR fuel has been evaluated to obtain the criticality of reactor. The reactor can achieve it criticality for U-235 enrichment in the loaded fresh fuel is at least 4.0 a% with the minimum fraction of the spent fuel in the core is 15.0 %. The neutron spectra become harder with the escalating of U-235 enrichment in the loaded fresh fuel as well as the amount of the spent fuel in the core.

Spent fuel dissolution studies FY 1991 to 1994

International Nuclear Information System (INIS)

Gray, W.J.; Wilson, C.N.

1995-12-01

Dissolution and transport as a result of groundwater flow are generally accepted as the primary mechanisms by which radionuclides from spent fuel placed in a geologic repository could be released to the biosphere. To help provide a source term for performance assessment calculations, dissolution studies on spent fuel and unirradiated uranium oxides have been conducted over the past few years at Pacific Northwest National Laboratory (PNNL) in support of the Yucca Mountain Site Characterization Project. This report describes work for fiscal years 1991 through 1994. The objectives of these studies and the associated conclusions, which were based on the limited number of tests conducted so far, are described in the following subsections

Introduction to the study of the treatment of spent nuclear fuel

International Nuclear Information System (INIS)

Floh, B.; Araujo, J.A. de; Matsuda, H.T.

1975-01-01

An introduction is made to the study of the treatment of spent nuclear fuels. Main topics discussed are: basic information, volatilization processes, treatment of thorium based fuels (Thorex process), analytical chemistry of spent nuclear fuel and design of industrial facilities

A safety study on the wet storage of spent fuel

International Nuclear Information System (INIS)

Chun, Kwan Sik; Whang, Joo Ho; Lee, Hoo Kun; Choi, Jong Won; Lee, Jong Geun

1989-02-01

This study is to provide data related with a basic design of the spent fuel storage facility in the field of radiation and to establish the safety assessment methodology of away from reactor spent fuel storage facility. This is in progress and continue upto the year of 1991. The mathematical model which predict the quantity of environmental release of fission and corrosion products from spent fuel received and stored in wet storage facility operated in normal conditions was prepared. The decay characteristic of domestic spent fuels are analysed and then the coefficients for the prediction of the decay heat by simple formular was determined. This correlations could predict decay heat of spent fuel with ±10% difference from ORIGEN2 results. The release factor of cobalt out of PWR spent fuel in PIE pool is 7.97 x 10-12∼8.49 x 10-11 Ci/ sec-rod, which appears to be linear without being connected with the types of fuel defects, but that of cesium varies with the defect type and the exposure time in water. In water condition, release factor of uranium out of CANDU fuel pellets appears to be about 5 x 10-8/day, whose tendency is similar to that of cesium of the latter half of the exposure time of water. (Author)

A durable and dependable solution for RTR spent fuel management

International Nuclear Information System (INIS)

Thomasson, J.

1999-01-01

RTR Operators need efficient and cost-effective services for the management of their spent fuel and this, for the full lifetime of their facility. Thanks to the integration of transport, reprocessing and conditioning services, COGEMA provides a cogent solution, with the utmost respect for safety and preservation of the environment, for the short, medium and long terms. As demonstrated in this paper, this option offers the only durable and dependable solution for the RTR spent fuel management, leading to a conditioning for the final residues directly suitable for final disposal. The main advantage of such an option is obviously the significant reduction in terms of volume and radiotoxicity of the ultimate waste when compared to direct disposal of spent fuels. The efficiency of such a solution has been proven, some RTR operators having already trusted COGEMA for the management of their aluminide fuel. With its commitment in R and D activities for the development of a high performance and reprocessable LEU fuels, COGEMA will be able to propose a solution for all types of fuels, HEU and LEU

Available Reprocessing and Recycling Services for Research Reactor Spent Nuclear Fuel

International Nuclear Information System (INIS)

2017-01-01

The high enriched uranium (HEU) take back programmes will soon have achieved their goals. When there are no longer HEU inventories at research reactors and no commerce in HEU for research reactors, the primary driver for the take back programmes will cease. However, research reactors will continue to operate in order to meet their various mission objectives. As a result, inventories of low enriched uranium spent nuclear fuel will continue to be created during the research reactors' lifetime and, therefore, there is a need to develop national final disposition routes. This publication is designed to address the issues of available reprocessing and recycling services for research reactor spent fuel and discusses the various back end management aspects of the research reactor fuel cycle.

Positron lifetime studies of 100-MeV oxygen irradiated Pb-doped Bi-2223 superconductors

NARCIS (Netherlands)

Banerjee, T.; Viswanath, R.N.; Kanjilal, D.; Kumar, R.; Ramasamy, S.

2000-01-01

Positron lifetime studies have been carried out for unirradiated and 100-MeV oxygen ion irradiated Pb-doped Bi-2223 superconductors. The analysis of positron lifetime spectra revealed three lifetime components: a short lifetime, τ1 = 153–196 ps; an intermediate lifetime, τ2 = 269–339 ps; and a long

Study on lifetime of C stripping foils

International Nuclear Information System (INIS)

Zhang Hongbin; Lu Ziwei; Zhao Yongtao; Li Zhankui; Xu Hushan; Xiao Guoqing; Wang Yuyu; Zhang Ling; Li Longcai; Fang Yan

2007-01-01

The carbon stripping foils can be prepared with the AC and DC arc discharge methods, or even sandwiched with AC-DC alternative layers. The lifetime of the carbon stripping foils of 19 μg/cm 2 prepared with different methods and/or structures was measured. The factors affecting the bombarding lifetime of the carbon stripping foils, especially the method of the foil preparation and the structure of the carbon stripping foils, were discussed. It is observed that the foils prepared with the DC arc discharge method have a longer bombarding lifetime than those prepared with the AC arc discharge method. (authors)

Positron annihilation lifetime study of oxide dispersion strengthened steels

International Nuclear Information System (INIS)

Krsjak, V.; Szaraz, Z.; Hähner, P.

2012-01-01

A comparative positron annihilation lifetime study has been performed on various commercial ferritic and ferritic/martensitic oxide dispersion strengthened (ODS) steels. Both as-extruded and recrystallized materials were investigated. In the materials with recrystallized coarse-grained microstructures, only the positron trapping at small vacancy clusters and yttria nanofeatures was observed. Materials which had not undergone recrystallization treatment clearly showed additional positron trapping which is associated with dislocations. Dislocation densities were calculated from a two-component decomposition of the positron lifetime spectra by assuming the first component to be a superposition of the bulk controlled annihilation rate and the dislocation controlled trapping rate. The second component (which translates into lifetimes of 240–260 ps) was found to be well separated in all those ODS materials. This paper presents the potentialities and limitations of the positron annihilation lifetime spectroscopy, and discusses the results of the experimental determination of the defect concentrations and sensitivity of this technique to the material degradation due to thermally induced precipitation of chromium-rich α′ phases.

Studies of Lifetimes in an Ion Storage Ring Using Laser Technique

International Nuclear Information System (INIS)

Rostohar, Danijela; Derkatch, Anna; Hartman, Henrik; Norlin, Lars-Olov; Royen, Peder; Schef, Peter; Mannervik, Sven

2003-01-01

The laser-probing method for lifetime measurements of metastable levels, performed by applying the Fast Ion Beam Laser (FIBLAS) method to ions stored in a storage ring, has been developed by the Stockholm group. Recently, we have applied this method to lifetime measurements of close lying metastable levels. In this paper we discuss experimental studies of ions with complex structure and present the first experimentally obtained lifetimes of selected metastable levels in complex systems as Fe + , Eu + and La + .

Understanding the prevalence of lifetime abstinence from alcohol: An ecological study.

Science.gov (United States)

Probst, Charlotte; Manthey, Jakob; Rehm, Jürgen

2017-09-01

The level of alcohol consumption and related burden in a country are strongly impacted by the prevalence of abstinence from alcohol use. The objective of this study was to characterize the association of lifetime abstinence from alcohol use with economic wealth (as measured in the gross domestic product [GDP]) and Muslim religion on a country level. An ecological study was performed using aggregate data of 183 countries for the year 2010. Lifetime abstinence among men and women was predicted using fractional response regression models with the natural logarithm of GDP-PPP (purchasing power parity) and the proportion of Muslim population as predictors. The models were further adjusted by the country's median age and World Health Organization region. Precision of prediction was investigated. Descriptive analyses showed a strong negative association between GDP-PPP and lifetime abstinence in countries without a Muslim majority and a GDP-PPP up to 20,000 international dollars. Regression models confirmed the negative association with GDP-PPP and showed a strong positive association between lifetime abstinence and the proportion of Muslim population. Stratified sensitivity analyses showed that in countries without a Muslim majority only GDP-PPP showed a statistically significant association whereas in Muslim majority countries only the proportion of Muslims was associated with the prevalence of lifetime abstinence. Particularly in countries with a lower GDP and without Muslim majority the prevalence of lifetime abstinence from alcohol use is strongly negatively associated with GDP-PPP. Future research should analyze the accordance in trends of GDP and lifetime abstinence over time. Copyright © 2017 Elsevier B.V. All rights reserved.

Minority Carrier Lifetime Studies of Narrow Bandgap Antimonide Superlattices

Science.gov (United States)

Hoglund, Linda; Ting, David Z.; Khoshakhlagh, Arezou; Soibel, Alexander; Hill, Cory J.; Fisher, Anita; Keo, Sam; Gunapala, Sarath D.

2014-01-01

In this study optical modulation response and photoluminescence spectroscopy were used to study mid-wave Ga-free InAs/InAsSb superlattices. The minority carrier lifetimes in the different samples varied from 480 ns to 4700 ns, partly due to different background doping concentrations. It was shown that the photoluminescence intensity can be used as a fast non-destructive tool to predict the material quality. It was also demonstrated that it is crucial to use a low excitation power in the photoluminescence measurements in order to get a good correlation between the photoluminescence intensity and the minority carrier lifetime.

Studies on recycling and utilization of spent catalysts. Preparation of active hydrodemetallization catalyst compositions from spent residue hydroprocessing catalysts

Energy Technology Data Exchange (ETDEWEB)

Marafi, Meena; Stanislaus, Antony [Petroleum Refining Department, Petroleum Research and Studies Center, Kuwait Institute for Scientific Research, P.O. Box 24885, Safat (Kuwait)

2007-02-15

Spent catalysts form a major source of solid wastes in the petroleum refining industries. Due to environmental concerns, increasing emphasis has been placed on the development of recycling processes for the waste catalyst materials as much as possible. In the present study the potential reuse of spent catalysts in the preparation of active new catalysts for residual oil hydrotreating was examined. A series of catalysts were prepared by mixing and extruding spent residue hydroprocessing catalysts that contained C, V, Mo, Ni and Al{sub 2}O{sub 3} with boehmite in different proportions. All prepared catalysts were characterized by chemical analysis and by surface area, pore volume, pore size and crushing strength measurements. The hydrodesulfurization (HDS) and hydrodemetallization (HDM) activities of the catalysts were evaluated by testing in a high pressure fixed-bed microreactor unit using Kuwait atmospheric residue as feed. A commercial HDM catalyst was also tested under similar operating conditions and their HDS and HDM activities were compared with that of the prepared catalysts. The results revealed that catalyst prepared with addition of up to 40 wt% spent catalyst to boehmite had fairly high surface area and pore volume together with large pores. The catalyst prepared by mixing and extruding about 40 wt% spent catalyst with boehmite was relatively more active for promoting HDM and HDS reactions than a reference commercial HDM catalyst. The formation of some kind of new active sites from the metals (V, Mo and Ni) present in the spent catalyst is suggested to be responsible for the high HDM activity of the prepared catalyst. (author)

Positron lifetime study of copper irradiated by energetic protons or energetic neutrons

International Nuclear Information System (INIS)

Howell, R.H.

1979-03-01

Positron lifetime measurements of pure copper damaged by irradiation with energetic protons and neutrons are presented. Lifetime determinations of the bulk material and various traps were made, and the dependence of the trapping rate on dose and irradiation energy were investigated. The results from the neutron- and proton-irradiated samples point to the existence of traps with similar but distinct lifetime parameters, not varying greatly from values reported in deformation studies. Also, a trap with long lifetime is seen for some proton irradiations, but is never seen for the neutron irradiations. The trapping rate of the short-lifetime trap is a linear function of dose for proton-irradiated samples and nearly so for the neutron irradiation. 1 figure

HTGR spent fuel storage study

International Nuclear Information System (INIS)

Burgoyne, R.M.; Holder, N.D.

1979-04-01

This report documents a study of alternate methods of storing high-temperature gas-cooled reactor (HTGR) spent fuel. General requirements and design considerations are defined for a storage facility integral to a fuel recycle plant. Requirements for stand-alone storage are briefly considered. Three alternate water-cooled storage conceptual designs (plug well, portable well, and monolith) are considered and compared to a previous air-cooled design. A concept using portable storage wells in racks appears to be the most favorable, subject to seismic analysis and economic evaluation verification

Predicting the Lifetimes of Nuclear Waste Containers

Science.gov (United States)

King, Fraser

2014-03-01

As for many aspects of the disposal of nuclear waste, the greatest challenge we have in the study of container materials is the prediction of the long-term performance over periods of tens to hundreds of thousands of years. Various methods have been used for predicting the lifetime of containers for the disposal of high-level waste or spent fuel in deep geological repositories. Both mechanical and corrosion-related failure mechanisms need to be considered, although until recently the interactions of mechanical and corrosion degradation modes have not been considered in detail. Failure from mechanical degradation modes has tended to be treated through suitable container design. In comparison, the inevitable loss of container integrity due to corrosion has been treated by developing specific corrosion models. The most important aspect, however, is to be able to justify the long-term predictions by demonstrating a mechanistic understanding of the various degradation modes.

Spent fuel workshop'2002

International Nuclear Information System (INIS)

Poinssot, Ch.

2002-01-01

This document gathers the transparencies of the presentations given at the 2002 spent fuel workshop: Session 1 - Research Projects: Overview on the IN CAN PROCESSES European project (M. Cowper), Overview on the SPENT FUEL STABILITY European project (C. Poinssot), Overview on the French R and D project on spent fuel long term evolution, PRECCI (C. Poinssot); Session 2 - Spent Fuel Oxidation: Oxidation of uranium dioxide single crystals (F. Garrido), Experimental results on SF oxidation and new modeling approach (L. Desgranges), LWR spent fuel oxidation - effects of burn-up and humidity (B. Hanson), An approach to modeling CANDU fuel oxidation under dry storage conditions (P. Taylor); Session 3 - Spent Fuel Dissolution Experiments: Overview on high burnup spent fuel dissolution studies at FZK/INE (A. Loida), Results on the influence of hydrogen on spent fuel leaching (K. Spahiu), Leaching of spent UO 2 fuel under inert and reducing conditions (Y. Albinsson), Fuel corrosion investigation by electrochemical techniques (D. Wegen), A reanalysis of LWR spent fuel flow through dissolution tests (B. Hanson), U-bearing secondary phases formed during fuel corrosion (R. Finch), The near-field chemical conditions and spent fuel leaching (D. Cui), The release of radionuclides from spent fuel in bentonite block (S.S. Kim), Trace actinide behavior in altered spent fuel (E. Buck, B. Hanson); Session 4 - Radiolysis Issues: The effect of radiolysis on UO 2 dissolution determined from electrochemical experiments with 238 Pu doped UO 2 M. Stroess-Gascoyne (F. King, J.S. Betteridge, F. Garisto), doped UO 2 studies (V. Rondinella), Preliminary results of static and dynamic dissolution tests with α doped UO 2 in Boom clay conditions (K. Lemmens), Studies of the behavior of UO 2 / water interfaces under He 2+ beam (C. Corbel), Alpha and gamma radiolysis effects on UO 2 alteration in water (C. Jegou), Behavior of Pu-doped pellets in brines (M. Kelm), On the potential catalytic behavior of

Effect of long-term storage of LWR spent fuel on Pu-thermal fuel cycle

International Nuclear Information System (INIS)

Kurosawa, Masayoshi; Naito, Yoshitaka; Suyama, Kenya; Itahara, Kuniyuki; Suzuki, Katsuo; Hamada, Koji

1998-01-01

According to the Long-term Program for Research, Development and Utilization of Nuclear Energy (June, 1994) in Japan, the Rokkasho Reprocessing Plant will be operated shortly after the year 2000, and the planning of the construction of the second commercial plant will be decided around 2010. Also, it is described that spent fuel storage has a positive meaning as an energy resource for the future utilization of Pu. Considering the balance between the increase of spent fuels and the domestic reprocessing capacity in Japan, it can be expected that the long-term storage of UO 2 spent fuels will be required. Then, we studied the effect of long-term storage of spent fuels on Pu-thermal fuel cycle. The burnup calculation were performed on the typical Japanese PWR fuel, and the burnup and criticality calculations were carried out on the Pu-thermal cores with MOX fuel. Based on the results, we evaluate the influence of extending the spent fuel storage term on the criticality safety, shielding design of the reprocessing plant and the core life time of the MOX core, etc. As the result of this work on long-term storage of LWR spent fuels, it becomes clear that there are few demerits regarding the lifetime of a MOX reactor core, and that there are many merits regarding the safety aspects of the fuel cycle facilities. Furthermore, long-term storage is meaningful as energy storage for effective utilization of Pu to be improved by technological innovation in future, and it will allow for sufficient time for the important policymaking of nuclear fuel cycle establishment in Japan. (author)

Positron annihilation lifetime study of radiation-damaged natural zircons

Energy Technology Data Exchange (ETDEWEB)

Roberts, J. [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra (Australia); Gaugliardo, P. [Centre for Antimatter-Matter Studies, School of Physics, University of Western Australia (Australia); Farnan, I.; Zhang, M. [Department of Earth Sciences, University of Cambridge (United Kingdom); Vance, E.R.; Davis, J.; Karatchevtseva, I.; Knott, R.B. [Australian Nuclear Science and Technology Organisation (Australia); Mudie, S. [The Australian Synchrotron, Victoria (Australia); Buckman, S.J. [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra (Australia); Institute for Mathematical Sciences, University of Malaya, Kuala Lumpur (Malaysia); Sullivan, J.P., E-mail: james.sullivan@anu.edu.au [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra (Australia)

2016-04-01

Zircons are a well-known candidate waste form for actinides and their radiation damage behaviour has been widely studied by a range of techniques. In this study, well-characterised natural single crystal zircons have been studied using Positron Annihilation Lifetime Spectroscopy (PALS). In some, but not all, of the crystals that had incurred at least half of the alpha-event damage of ∼10{sup 19} α/g required to render them structurally amorphous, PALS spectra displayed long lifetimes corresponding to voids of ∼0.5 nm in diameter. The long lifetimes corresponded to expectations from published Small-Angle X-ray Scattering data on similar samples. However, the non-observation by PALS of such voids in some of the heavily damaged samples may reflect large size variations among the voids such that no singular size can be distinguished or. Characterisation of a range of samples was also performed using scanning electron microscopy, optical absorption spectroscopy, Raman scattering and X-ray scattering/diffraction, with the degree of alpha damage being inferred mainly from the Raman technique and X-ray diffraction. The observed void diameters and intensities of the long lifetime components were changed somewhat by annealing at 700 °C; annealing at 1200 °C removed the voids entirely. The voids themselves may derive from He gas bubbles or voids created by the inclusion of small quantities of organic and hydrous matter, notwithstanding the observation that no voidage was evidenced by PALS in two samples containing hydrous and organic matter. - Highlights: • Study of a range of naturally occurring zircons damaged by alpha radiation. • Characterised using a range of techniques, including PALS spectroscopy. • Effects on hydrous material appear important, rather than direct radiation damage. • Annealing is shown to remove the observed voids.

Positron annihilation lifetime and photoluminescence studies on single crystalline ZnO

Energy Technology Data Exchange (ETDEWEB)

Sarkar, A [Department of Physics, Bangabasi Morning College, 19 Rajkumar Chakraborty Sarani, Kolkata 700 009 (India); Chakrabarti, Mahuya [Department of Physics, University of Calcutta, 92 Acharya Prafulla Chandra Road, Kolkata 700009 (India); Ray, S K [Department of Physics and Meteorology, Indian Institute of Technology, Kharagpur (India); Bhowmick, D; Sanyal, D, E-mail: dirtha@vecc.gov.in [Variable Energy Cyclotron Centre, 1/AF, Bidhannagar, Kolkata 700064 (India)

2011-04-20

The room temperature positron annihilation lifetime for single crystalline ZnO has been measured as 164 {+-} 1 ps. The single component lifetime value is very close to but higher than the theoretically predicted value of {approx} 154 ps. Photoluminescence study (at 10 K) indicates the presence of hydrogen and other defects, mainly acceptor related, in the crystal. Defects related to a lower open volume than zinc vacancies, presumably a complex with two hydrogen atoms, are the major trapping sites in the sample. The bulk positron lifetime in ZnO is expected to be a little less than 164 ps.

Positron annihilation lifetime and photoluminescence studies on single crystalline ZnO

Science.gov (United States)

Sarkar, A.; Chakrabarti, Mahuya; Ray, S. K.; Bhowmick, D.; Sanyal, D.

2011-04-01

The room temperature positron annihilation lifetime for single crystalline ZnO has been measured as 164 ± 1 ps. The single component lifetime value is very close to but higher than the theoretically predicted value of ~ 154 ps. Photoluminescence study (at 10 K) indicates the presence of hydrogen and other defects, mainly acceptor related, in the crystal. Defects related to a lower open volume than zinc vacancies, presumably a complex with two hydrogen atoms, are the major trapping sites in the sample. The bulk positron lifetime in ZnO is expected to be a little less than 164 ps.

Positron annihilation lifetime and photoluminescence studies on single crystalline ZnO

International Nuclear Information System (INIS)

Sarkar, A; Chakrabarti, Mahuya; Ray, S K; Bhowmick, D; Sanyal, D

2011-01-01

The room temperature positron annihilation lifetime for single crystalline ZnO has been measured as 164 ± 1 ps. The single component lifetime value is very close to but higher than the theoretically predicted value of ∼ 154 ps. Photoluminescence study (at 10 K) indicates the presence of hydrogen and other defects, mainly acceptor related, in the crystal. Defects related to a lower open volume than zinc vacancies, presumably a complex with two hydrogen atoms, are the major trapping sites in the sample. The bulk positron lifetime in ZnO is expected to be a little less than 164 ps.

Lifetime costs of cerebral palsy

DEFF Research Database (Denmark)

Kruse, Marie; Michelsen, Susan Ishøy; Flachs, Esben Meulengracht

2009-01-01

This study quantified the lifetime costs of cerebral palsy (CP) in a register-based setting. It was the first study outside the US to assess the lifetime costs of CP. The lifetime costs attributable to CP were divided into three categories: health care costs, productivity costs, and social costs....... social care costs and productivity costs associated with CP point to a potential gain from labour market interventions that benefit individuals with CP.......This study quantified the lifetime costs of cerebral palsy (CP) in a register-based setting. It was the first study outside the US to assess the lifetime costs of CP. The lifetime costs attributable to CP were divided into three categories: health care costs, productivity costs, and social costs...... in 2000. The prevalence of CP in eastern Denmark was approximately 1.7 per 1000. Information on productivity and the use of health care was retrieved from registers. The lifetime cost of CP was about euro860 000 for men and about euro800 000 for women. The largest component was social care costs...

Spent fuels program

International Nuclear Information System (INIS)

Shappert, L.B.

1983-01-01

The goal of this task is to support the Domestic Spent Fuel Storage Program through studies involving the transport of spent fuel. A catalog was developed to provide authoritative, timely, and accessible transportation information for persons involved in the transport of irradiated reactor fuel. The catalog, drafted and submitted to the Transportation Technology Center, Sandia National Laboratories, for their review and approval, covers such topics as federal, state, and local regulations, spent fuel characteristics, cask characteristics, transportation costs, and emergency response information

Spent nuclear fuel project design basis capacity study

Energy Technology Data Exchange (ETDEWEB)

Cleveland, K.J.

1996-09-09

A parametric study of the Spent Nuclear Fuel Project system capacity is presented. The study was completed using a commercially available software package to develop a summary level model of the major project systems. Alternative configurations, sub-system cycle times, and operating scenarios were tested to identify their impact on total project duration and equipment requirements.

DC photogun vacuum characterization through photocathode lifetime studies

International Nuclear Information System (INIS)

Marcy Stutzman; Joseph Grames; Matt Poelker; Kenneth Surles-Law; Philip Adderley

2007-01-01

Excellent vacuum is essential for long photocathode lifetimes in DC high voltage photoelectron guns. Vacuum Research at Thomas Jefferson National Accelerator Facility has focused on characterizing the existing vacuum systems at the CEBAF polarized photoinjector and on quantifying improvements for new systems. Vacuum chamber preprocessing, full activation of NEG pumps and NEG coating the chamber walls should improve the vacuum within the electron gun, however, pressure measurement is difficult at pressures approaching the extreme-high-vacuum (XHV) region and extractor gauge readings are not significantly different between the improved and original systems. The ultimate test of vacuum in a DC high voltage photogun is the photocathode lifetime, which is limited by the ionization and back-bombardment of residual gasses. Discussion will include our new load-locked gun design as well as lifetime measurements in both our operational and new photo-guns, and the correlations between measured vacuum and lifetimes will be investigated

Study of straw chamber lifetime with argon ethane

International Nuclear Information System (INIS)

Adler, J.; Bolton, T.; Bunnell, K.; Cheu, E.; Grab, C.; Mazaheri, G.; Odian, A.; Pitman, D.; Stockhausen, W.; Toki, W.; Wadley, W.; Wood, C.; Mir, R.

1989-01-01

We present detailed laboratory measurements of the lifetime of a small test chamber, simulating the Mark III straw vertex chamber conditions. The tests were carried out with an argon-ethane 50/50 gas mixture at 3 atm absolute pressure and 3.9 kV applied to the wires. After the accumulation of ≅ 0.02 C/cm on a single straw, continuous discharges began. The addition of alcohol or water vapor to the gas mixture was found to extend the lifetime of the straws. Continuous flow of the gas mixture with water vapor through the straws prolonged the lifetime significantly. We present results on the effects of changing the gas mixture inside the straws at regular time intervals. Adding a small percentage of water vapor to the argon-ethane gas and flowing the gas mixture in the straws can improve the lifetime by more than an order of magnitude. An accumulated charge of 1.0 C/cm on a single straw has been obtained. (orig.)

Lifetime-management and lifetime-extension at PAKS nuclear power plant

International Nuclear Information System (INIS)

Katona, Tamas; Ratkai, Sandor; Janosi, Agnes Biro

2002-01-01

Paks Nuclear Power Plant provides 38-40% of domestic generation at lowest price. It has an important energy-policy role in Hungary. NPP Paks shall be a decisive and perspectively permanent element of the domestic electricity generation during the next two decades, which shall be ensured by plant safe operation, the lifetime extension and power uprating. Paks Nuclear Power Plant investigated the nuclear power plant's lifetime extension possibilities and alternatives, as well as technical and business feasibility of such alternatives. The feasibility study is based on the evaluation of a representative set of systems, structures and components, operational, test, in-service inspection and maintenance practice, experience and findings of the Periodic Safety Review. The most important results of this study showing the feasibility of 20 years lifetime extension is summarised in the paper. It was found that there are no technical or safety issues or limits, which may inhibit the operation of the Nuclear Power Plant Paks up to 50 years. In case of most systems and equipment the recent monitoring, maintenance and regular reconstruction practice of the NPP Paks allows the lifetime extension without outstanding cost. Replacement or reconstruction of a few equipment and systems requires significant investment costs. Material of reactor vessels of VVER/213 incorporated at Paks, compared to vessels of the similar units, is less sensitive to the embrittlement. At units 3-4 reactor vessels do not require any measure, consequently, any additional cost, even in case of a lifetime of 50 years. At unit 2 to extend the lifetime of the reactor vessel, only heating-up of emergency core cooling tanks is needed in order to decrease thermal stress levels caused by pressure thermal shock (PST) transients. For this purpose cost-effective technical solutions are available. At unit 1, beside the heating-up of the emergency core cooling tanks annealing of the welded joint No. 5/6 close to the

Economics of National Waste Terminal Storage Spent Fuel Pricing Study

International Nuclear Information System (INIS)

1978-05-01

The methodology for equitably pricing commercial nuclear spent fuel management is developed, and the results of four sample calculations are presented. The spent fuel management program analyzed places encapsulated spent fuel in bedded salt while maintaining long-term retrievability. System design was reasonable but not optimum. When required, privately-owned Away From Reactor (AFR) storage is provided and the spent fuel placed in AFR storage is eventually transported to final storage. Applicable Research and Development and Government Overhead are included. The cost of each component by year was estimated from the most recent applicable data source available. These costs were input to the pricing methodology to establish a one-time charge whose present value exactly recovered the present value of the expenditure flow. The four cases exercised were combinations of a high and a low quantity of spent fuel managed, with a single repository (venture) or a multiple repository (campaign) approach to system financial structure. The price for spent fuel management calculated ranged from 116 to 152 dollars (1978) per kilogram charged initially to the reactor. The effect of spent fuel receiving rate on price is illustrated by the fact that the extremes of price did not coincide with the cases having the extremes of undiscounted cost. These prices for spent fuel management are comparable in magnitude to other fuel cycle costs. The range of variation is small because of compensating effects, i.e., additional costs for high early deliveries (AFR and transportation) versus lower present value of future revenue for later delivery cases. The methodology contains numerous conservative assumptions, provisions for contingencies, and covers the complete set of spent fuel management expenses

Study on Effect of Junction Temperature Swing Duration on Lifetime of Transfer Molded Power IGBT Modules

DEFF Research Database (Denmark)

Choi, Uimin; Blaabjerg, Frede; Jørgensen, Søren

2017-01-01

levels are presented. This study enables to include the tΔTj effect on lifetime model of IGBT modules for its lifetime estimation and it may result in improved lifetime prediction of IGBT modules under given mission profiles of converters. A postfailure analysis of the tested IGBT modules is also......In this paper, the effect of junction temperature swing duration on lifetime of transfer molded power insulated gate bipolar transistor (IGBT) modules is studied and a relevant lifetime factor is modeled. This study is based on 39 accelerated power cycling test results under six different...

Spent fuel workshop'2002

Energy Technology Data Exchange (ETDEWEB)

Poinssot, Ch

2002-07-01

This document gathers the transparencies of the presentations given at the 2002 spent fuel workshop: Session 1 - Research Projects: Overview on the IN CAN PROCESSES European project (M. Cowper), Overview on the SPENT FUEL STABILITY European project (C. Poinssot), Overview on the French R and D project on spent fuel long term evolution, PRECCI (C. Poinssot); Session 2 - Spent Fuel Oxidation: Oxidation of uranium dioxide single crystals (F. Garrido), Experimental results on SF oxidation and new modeling approach (L. Desgranges), LWR spent fuel oxidation - effects of burn-up and humidity (B. Hanson), An approach to modeling CANDU fuel oxidation under dry storage conditions (P. Taylor); Session 3 - Spent Fuel Dissolution Experiments: Overview on high burnup spent fuel dissolution studies at FZK/INE (A. Loida), Results on the influence of hydrogen on spent fuel leaching (K. Spahiu), Leaching of spent UO{sub 2} fuel under inert and reducing conditions (Y. Albinsson), Fuel corrosion investigation by electrochemical techniques (D. Wegen), A reanalysis of LWR spent fuel flow through dissolution tests (B. Hanson), U-bearing secondary phases formed during fuel corrosion (R. Finch), The near-field chemical conditions and spent fuel leaching (D. Cui), The release of radionuclides from spent fuel in bentonite block (S.S. Kim), Trace actinide behavior in altered spent fuel (E. Buck, B. Hanson); Session 4 - Radiolysis Issues: The effect of radiolysis on UO{sub 2} dissolution determined from electrochemical experiments with {sup 238}Pu doped UO{sub 2} M. Stroess-Gascoyne (F. King, J.S. Betteridge, F. Garisto), doped UO{sub 2} studies (V. Rondinella), Preliminary results of static and dynamic dissolution tests with {alpha} doped UO{sub 2} in Boom clay conditions (K. Lemmens), Studies of the behavior of UO{sub 2} / water interfaces under He{sup 2+} beam (C. Corbel), Alpha and gamma radiolysis effects on UO{sub 2} alteration in water (C. Jegou), Behavior of Pu-doped pellets in brines

Positron annihilation lifetime study of low temperature irradiated metals

Energy Technology Data Exchange (ETDEWEB)

Kuramoto, Eiichi [Kyushu Univ., Kasuga, Fukuoka (Japan). Research Inst. for Applied Mechanics

1997-11-01

Positron annihilation lifetime measurements have been made for electron and neutron irradiated Fe, Fe-Cr, Fe-Cu, Fe-Si, Fe-16Cr-17Ni specimens, and isochronal annealing behaviors were obtained for these metals and alloys. It was found that vacancies start to migrate at about 200 K in Fe and form microvoids, but by the addition of small amount of alloying elements this behavior was changed depending on the alloying elements. Positron lifetime calculations were made to explain the experimental results using EAM (embedded atom method) type potential for the lattice relaxation and the atomic superposition method for the lifetime calculation. Fairly good agreements were obtained for the positron lifetime in a vacancy in Fe and other alloys. (author)

Positron annihilation lifetime spectroscopy study of Kapton thin foils

Science.gov (United States)

Kanda, G. S.; Ravelli, L.; Löwe, B.; Egger, W.; Keeble, D. J.

2016-01-01

Variable energy positron annihilation lifetime spectroscopy (VE-PALS) experiments on polyimide material Kapton are reported. Thin Kapton foils are widely used in a variety of mechanical, electronic applications. PALS provides a sensitive probe of vacancy-related defects in a wide range of materials, including open volume in polymers. Varying the positron implantation energy enables direct measurement of thin foils. Thin Kapton foils are also commonly used to enclose the positron source material in conventional PALS measurements performed with unmoderated radionuclide sources. The results of depth-profiled positron lifetime measurements on 7.6 μm and 25 μm Kapton foils are reported and determine a dominant 385(1) ps lifetime component. The absence of significant nanosecond lifetime component due to positronium formation is confirmed.

Dynamic lifetimes of cagelike water clusters immersed in liquid water and their implications for hydrate nucleation studies

Energy Technology Data Exchange (ETDEWEB)

Guo, G.J.; Zhang, Y.G.; Li, M.; Wu, C.H. [Chinese Academy of Sciences, Inst. of Geology and Geophysics, Beijing (China). Key Laboratory of the Study of Earth' s Deep Interior

2008-07-01

In hydrate research fields, the hydrate nucleation mechanism still remains as an unsolved question. The static lifetimes of cagelike water clusters (CLWC) immersed in bulk liquid water have recently been measured by performing molecular dynamics simulations in the methane-water system, during which the member-water molecules of CLWCs are not allowed to exchange with their surrounding water molecules. This paper presented a study that measured the dynamic lifetimes of CLWCs permitting such water exchanges. The study involved re-analysis of previous simulation data that were used to study the effect of methane adsorption on the static lifetimes of a dodecahedral water cluster (DWC). The dynamic lifetimes of the DWC were calculated. The results of lifetime measurements of DWC in different systems were provided. The implications of this study for hydrate nucleation were also discussed. It was found that the dynamic lifetimes of CLWCs were not less than the static lifetimes previously obtained, and their ratio increased with the lifetime values. The results strengthened that CLWCs are metastable structures in liquid water and the occurrence probability of long-lived CLWCs will increase if one uses the dynamic lifetimes instead of the static lifetimes. 13 refs., 1 tab., 3 figs.

BWR Spent Nuclear Fuel Interfacial Bonding Efficiency Study

Energy Technology Data Exchange (ETDEWEB)

Wang, Jy-An John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jiang, Hao [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-04-30

The objective of this project is to perform a systematic study of spent nuclear fuel (SNF, also known as “used nuclear fuel” [UNF]) integrity under simulated transportation environments using the Cyclic Integrated Reversible-Bending Fatigue Tester (CIRFT) hot-cell testing technology developed at Oak Ridge National Laboratory (ORNL) in August 2013. Under Nuclear Regulatory Commission (NRC) sponsorship, ORNL completed four benchmark tests, four static tests, and twelve dynamic or cycle tests on H. B. Robinson (HBR) high burn-up (HBU) fuel. The clad of the HBR fuels was made of Zircaloy-4. Testing was continued in fiscal year (FY) 2014 using Department of Energy (DOE) funds. Additional CIRFT testing was conducted on three HBR rods; two specimens failed, and one specimen was tested to over 2.23 × 10⁷ cycles without failing. The data analysis on all the HBR SNF rods demonstrated that it is necessary to characterize the fatigue life of the SNF rods in terms of (1) the curvature amplitude and (2) the maximum absolute of curvature extremes. The maximum extremes are significant because they signify the maximum tensile stress for the outer fiber of the bending rod. CIRFT testing has also addressed a large variation in hydrogen content on the HBR rods. While the load amplitude is the dominant factor that controls the fatigue life of bending rods, the hydrogen content also has an important effect on the lifetime attained at each load range tested. In FY 15, eleven SNF rod segments from the Limerick BWR were tested using the ORNL CIRFT equipment; one test under static conditions and ten tests under dynamic loading conditions. Under static unidirectional loading, a moment of 85 N·m was obtained at a maximum curvature of 4.0 m^-1. The specimen did not show any sign of failure during three repeated loading cycles to a similar maximum curvature. Ten cyclic tests were conducted with amplitudes varying from 15.2 to 7.1 N·m. Failure was observed in nine of

Spent fuel management in Japan

International Nuclear Information System (INIS)

Mineo, H.; Nomura, Y.; Sakamoto, K.

1998-01-01

In Japan 52 commercial nuclear power units are now operated, and the total power generation capacity is about 45 GWe. The cumulative amount of spent fuel arising is about 13,500 tU as of March 1997. Spent fuel is reprocessed, and recovered nuclear materials are to be recycled in LWRs and FBRs. In February 1997 short-term policy measures were announced by the Atomic Energy Commission, which addressed promotion of reprocessing programme in Rokkasho, plutonium utilization in LWRs, spent fuel management, backend measures and FBR development. With regard to the spent fuel management, the policy measures included expansion of spent fuel storage capacity at reactor sites and a study on spent fuel storage away from reactor sites, considering the increasing amount of spent fuel arising. Research and development on spent fuel storage has been carried out, particularly on dry storage technology. Fundamental studies are also conducted to implement the burnup credit into the criticality safety design of storage and transportation casks. Rokkasho reprocessing plant is being constructed towards its commencement in 2003, and Pu utilization in LWRs will be started in 1999. Research and development of future recycling technology are also continued for the establishment of nuclear fuel cycle based on FBRs and LWRs. (author)

A study on the expulsion of iodine from spent-fuel solutions

Energy Technology Data Exchange (ETDEWEB)

Sakurai, Tsutomu; Takahashi, Akira; Ishikawa, Niroh [Japan Atomic Energy Research Institute, Ibaraki-ken (Japan)] [and others

1995-02-01

During dissolution of spent nuclear fuels, some radioiodine remains in spent-fuel solutions. Its expulsion to dissolver off-gas is important to minimize iodine escape to the environment. In our current work, the iodine remaining in spent-fuel solutions varied from 0 to 10% after dissolution of spent PWR-fuel specimens (approximately 3 g each). The amount remaining probably was dependent upon the dissolution time required. The cause is ascribable to the increased nitrous acid concentration that results from NOx generated during dissolution. The presence of nitrous acid was confirmed spectrophotometrically in an NO-HNO{sub 3} system at 100{degrees}C. Experiments examining NOx concentration versus the quantity of iodine in a simulated spent-fuel solution indicate that iodine (I{minus}) in spent fuels is subjected to the following three reactions: (1) oxidation into I{sub 2} by nitric acid, (2) oxidation into I{sub 2} by nitrous acid arising from NOx, and (3) formation of colloidal iodine (AgI, PdI{sub 2}), the major iodine species in a spent-fuel solution. Reaction (2) competes with reaction (3) to control the quantity of iodine remaining in solution. The following two-step expulsion process to remove iodine from a spent-fuel solution was derived from these experiments: Step One - Heat spent-fuel solutions without NOx sparging. When aged colloidal iodine is present, an excess amount of iodate should be added to the solution. Step Two - Sparge the fuel solution with NOx while heating. Effect of this new method was confirmed by use of a spent PWR-fuel solution.

HEU and Leu FueL Shielding Comparative Study Applied for Spent Fuel Transport

International Nuclear Information System (INIS)

Margeanu, C.A.; Margeanu, S.; Barbos, D.

2009-01-01

INR Pitesti owns and operates a TRIGA dual-core Research Reactor for material testing, power reactor fuel and nuclear safety studies. The dual core concept involves the operation of a 14 MW TRIGA steady-state, high flux research and material testing reactor at one end of a large pool, and the independent operation of an annular-core pulsing reactor (TRIGA-ACPR) at the other end of the pool. The steady-state reactor is mostly used for long term testing of power reactor fuel components (pellets, pins, subassemblies and fuel assemblies) followed by post-irradiation examination. Following the general trend to replace the He fuel type (High Enriched Uranium) by Leu fuel type (Low Enriched Uranium), in the light of international agreements between IAEA and the states using He fuel in their nuclear reactors, Inr Past's have been accomplished the TRIGA research reactor core full conversion on May 2006. The He fuel repatriation in US in the frame of Foreign Research Reactor Spent Nuclear Fuel Return Programme effectively started in 1999, the final stage being achieved in summer of 2008. Taking into account for the possible impact on the human and environment, in all activities associated to nuclear fuel cycle, the spent fuel or radioactive waste characteristics must be well known. Shielding calculations basic tasks consist in radiation doses calculation, in order to prevent any risks both for personnel protection and impact on the environment during the spent fuel manipulation, transport and storage. The paper is a comparative study of Leu and He fuel utilization effects for the shielding analysis during spent fuel transport. A comparison against the measured data for He spent fuel, available from the last stage of the spent fuel repatriation, is presented. All the geometrical and material data related on the spent fuel shipping cask were considered according to the Nac-Lt Cask approved model. The shielding analysis estimates radiation doses to shipping cask wall surface

Implications of the Croatian Spent Fuel and Radioactive Waste Strategy

International Nuclear Information System (INIS)

Lokner, V.; Levanat, I.

2012-01-01

Croatian Government approved its national Radioactive waste and Spent Fuel Strategy as a part of the accession process to EU in July 2009 enabling acquisition of adequate administrative capacity by the time of accession to properly implement and enforce the relevant legislation in all areas related to nuclear safety. Strategy was formulated in line with the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management. In particular, the strategy was approved to ensure that sufficient qualified staff and adequate financial services are available to support the safety of facilities for spent fuel and radioactive waste management generated by Krsko NPP during their operating lifetime and from decommissioning. Following are statements from the Croatian strategy that are relevant for Croatian position regarding capacity building for storage and disposal of LILW and SF. To be able to fulfill the obligations assumed, Croatia needs to do the following (Strategy Section 3.3): reach an agreement with Slovenia by 2013 at the latest regarding the location of objects for storing LILW; should no such agreement be reached, Croatia is to initiate preparations for assuming its half of operational LILW and for third-country export thereof, or for storing the LILW on Croatian territory, whilst also gradually assuming the part of LILW created from decommissioning; reach an agreement with Slovenia by 2018 at the latest regarding the location of a common SF storage; should no such agreement be reached, initiate preparations for assuming a third-country export of SF, or for storing half of SF on Croatian territory. This paper discusses the Strategy aims in the light of noticeable delay of 2nd revision of the Program of NPP Krsko Decommissioning and SF andLILW Disposal, the status of the planned Slovenian national repository on Vrbina site and the prospects of its use for joint Croatian/Slovenian LILW disposal - all in the context of as yet

Intermediate storage of radioactive waste and spent nuclear fuel at the Kola Peninsula

International Nuclear Information System (INIS)

Bohmer, N.

1999-01-01

The problem of nuclear waste and disused nuclear submarines are a product of the arms race and the Cold War. Russia still continues to build new nuclear submarines, but there are very few provisions being made to properly store old nuclear submarines, and develop sufficient storage facilities for spent nuclear fuel and other radioactive waste. A solution to this problem is proposed: to construct a new regional interim storage facilities at Kola for the spent nuclear fuel instead of transporting it to Mayak, the existing reprocessing plant. This storage should have the capacity to handle the fuel in the existing storage and the fuel still on board of retired nuclear submarines. Its lifetime should be 50 years. later it would be possible to make a decision on the future of this fuel

Comprehensive studies on regulatory issues of spent fuel pools

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-08-15

An existence of safety issues in the spent fuel pool (SFP) was recognized by the nuclear accident at the Fukushima Daiichi Nuclear Power Station, and many reports on the accident describe needs of countermeasures for SFP under sever accidents. For research planning, thermal hydraulic behaviors of SFP and possibility of occurrence of re-criticality conditions in SFP were studied by computational approaches. In the studies on thermal hydraulic behaviors, possibilities of adiabatic conditions in a spent fuel bundle were identified because natural circulation cooling of air could be terminated due to flow path blockage by pool water and steam cooling could be terminated due to reduction of pool water evaporation originated from cold water injection by emergency water supply. In the re-criticality study, in the case of the un-borated lack, it was shown that the neutron multiplication factor became larger than unity when the difference of water levels inside and outside the channel box larger than some values. (author)

Feasibility study on utilization of radiation from spent fuel in storage facility

International Nuclear Information System (INIS)

Wataru, Masumi; Sakamoto, Kazuaki; Saegusa, Toshiari; Sakaya, Tadatsugu; Fujiwara, Hiroaki.

1997-01-01

Spent fuels of nuclear power plant are stored safely until reprocessing because they are radioactive in addition to energy resources. It is foreseen that the amount of the stored spent fuel increases in the long term. Therefore, in the government, discussion on the storage away from reactor is in progress as well as one at reactor. Spent fuel emits a radioactive ray for a long time. In the storage facility, radiation is shielded not to have a detrimental influence upon the health and environment. If radioactive ray is incorrectly handled, it is hazardous for the health and the environment. But, it is very useful if it is properly utilized under a careful management. In the industry, radioactive ray by isotopes (e.g. Co-60) is used widely. In a view of the effective utilization of energy, the promotion of the siting, the regional development and the creation of employment opportunities of local inhabitants, it is preferable to make use of radiation from the spent fuel. In this study, feasibility of utilization of radiation energy from the spent fuel in a storage facility was evaluated. (author)

Lifetimes of heavy flavour particles

International Nuclear Information System (INIS)

Forty, R.

1994-01-01

The lifetimes of heavy-flavour hadrons are reviewed. After a brief discussion of the theoretical predictions, the problem of averaging lifetime measurements is discussed. The various experimental measurements are then presented and suitable averages performed. Charmed meson lifetimes are now measured to the few percent level, better that theory can predict, whilst for charmed baryons the lifetime hierarchy has been established for the first time. For beauty hadrons the lifetimes are measured at the 6-10 % level, and are in reasonable agreement with theoretical expectations. Beauty baryon studies ar just beginning. (author)

Centralized disassembly and packaging of spent fuel in the DOE spent fuel management system

International Nuclear Information System (INIS)

Johnson, E.R.

1986-01-01

In October 1984, E.R. Johnson Associates, Inc. (JAI) initiated a study of the prospective use of a centralized facility for the disassembly and packaging of spent fuel to support the various elements of the US Dept. of Energy (DOE) spent fuel management system, including facilities for monitored retrievable storage (MRS) and repositories. It was DOE's original plan to receive spent fuel at each repository where it would be disassembled and packaged (overpacked) for disposal purposes. Subsequently, DOE considered the prospective use of MRS of spent fuel as an option for providing safe and reliable management of spent fuel. This study was designed to consider possible advantages of the use of centralized facilities for disassembly and packaging of spent fuel at whose location storage facilities could be added as required. The study was divided into three principal technical tasks that covered: (a) development of requirements and criteria for the central disassembly and packaging facility and associated systems. (2) Development of conceptual designs for the central disassembly and packaging facility and associated systems. (3) Estimation of capital and operating costs involved for all system facilities and determination of life cycle costs for various scenarios of operation - for comparison with the reference system

Spent-fuel-stabilizer screening studies

International Nuclear Information System (INIS)

Wynhoff, N.; Girault, S.E.; Fish, R.L.

1980-11-01

A broad range of potential stabilizer materials was identified and screened for packaging spent fuel assemblies for underground storage. The screening took into consideration the thermal gradient, stress, differential thermal expansion, nuclear criticality, radiation shielding, cost, and availability. Recommended stabilizer materials for further testing include silica, quartz, mullite, zircon, bentonite, graphite, gases, lead, Zn alloys, Cu alloys, etc

Lifetime total and beverage specific - alcohol intake and prostate cancer risk: a case-control study

Directory of Open Access Journals (Sweden)

Carruba Giuseppe

2004-12-01

Full Text Available Abstract Background We investigated lifetime alcohol consumption and prostate cancer risk in a case-control study conducted in Buffalo, NY (1998–2001. Methods The study included 88 men, aged 45 to 85 years with incident, histologically-confirmed prostate cancer and 272 controls. We conducted extensive in-person interviews regarding lifetime alcohol consumption and other epidemiologic data. Results Prostate cancer risk was not associated with lifetime intake of total and beverage specific ethanol. In addition we found no association with number of drinks per day (average drinks per day over the lifetime or drinks per drinking day (average drinks per day on drinking days only over the lifetime. However, we observed an inverse association with the total number of drinking years. Men in the lowest tertile of total drinking years had a two-fold prostate cancer risk than men in the highest tertile (OR 2.16, 95% CI 0.98–4.78, p for trend Conclusion Our results suggest that alcohol intake distribution across lifetime may play a more important role in prostate cancer etiology than total lifetime consumption.

Activation analysis of dual-purpose metal cask after the end of design lifetime for decommission

Energy Technology Data Exchange (ETDEWEB)

Kim, Tae Man; Ku, Ji Young; Dho Ho Seog; Cho, Chun Hyung [Korea Radioactive Waste Agency, Daejeon (Korea, Republic of); Ko, Jae Hun [Korea Nuclear Engineering and Service Co., Daejeon (Korea, Republic of)

2016-12-15

The Korea Radioactive Waste Agency (KORAD) has developed a dual-purpose metal cask for the dry storage of spent nuclear fuel that has been generated by domestic light-water reactors. The metal cask was designed in compliance with international and domestic technology standards, and safety was the most important consideration in developing the design. It was designed to maintain its integrity for 50 years in terms of major safety factors. The metal cask ensures the minimization of waste generated by maintenance activities during the storage period as well as the safe management of the waste. An activation evaluation of the main body, which includes internal and external components of metal casks whose design lifetime has expired, provides quantitative data on their radioactive inventory. The radioactive inventory of the main body and the components of the metal cask were calculated by applying the MCNP5·ORIGEN-2 evaluation system and by considering each component's chemical composition, neutron flux distribution, and reaction rate, as well as the duration of neutron irradiation during the storage period. The evaluation results revealed that 10 years after the end of the cask's design life, {sup 60}Co had greater radioactivity than other nuclides among the metal materials. In the case of the neutron shield, nuclides that emit high-energy gamma rays such as {sup 28}Al and {sup 24}Na had greater radioactivity immediately after the design lifetime. However, their radioactivity level became negligible after six months due to their short half-life. The surface exposure dose rates of the canister and the main body of the metal cask from which the spent nuclear fuel had been removed with expiration of the design lifetime were determined to be at very low levels, and the radiation exposure doses to which radiation workers were subjected during the decommissioning process appeared to be at insignificant levels. The evaluations of this study strongly suggest that

Age at Menarche and Time Spent in Education: A Mendelian Randomization Study.

Science.gov (United States)

Gill, D; Del Greco M, F; Rawson, T M; Sivakumaran, P; Brown, A; Sheehan, N A; Minelli, C

2017-09-01

Menarche signifies the primary event in female puberty and is associated with changes in self-identity. It is not clear whether earlier puberty causes girls to spend less time in education. Observational studies on this topic are likely to be affected by confounding environmental factors. The Mendelian randomization (MR) approach addresses these issues by using genetic variants (such as single nucleotide polymorphisms, SNPs) as proxies for the risk factor of interest. We use this technique to explore whether there is a causal effect of age at menarche on time spent in education. Instruments and SNP-age at menarche estimates are identified from a Genome Wide Association Study (GWAS) meta-analysis of 182,416 women of European descent. The effects of instruments on time spent in education are estimated using a GWAS meta-analysis of 118,443 women performed by the Social Science Genetic Association Consortium (SSGAC). In our main analysis, we demonstrate a small but statistically significant causal effect of age at menarche on time spent in education: a 1 year increase in age at menarche is associated with 0.14 years (53 days) increase in time spent in education (95% CI 0.10-0.21 years, p = 3.5 × 10 -8 ). The causal effect is confirmed in sensitivity analyses. In identifying this positive causal effect of age at menarche on time spent in education, we offer further insight into the social effects of puberty in girls.

Disposal of spent fuel

International Nuclear Information System (INIS)

Blomeke, J.O.; Ferguson, D.E.; Croff, A.G.

1978-01-01

Based on preliminary analyses, spent fuel assemblies are an acceptable form for waste disposal. The following studies appear necessary to bring our knowledge of spent fuel as a final disposal form to a level comparable with that of the solidified wastes from reprocessing: 1. A complete systems analysis is needed of spent fuel disposition from reactor discharge to final isolation in a repository. 2. Since it appears desirable to encase the spent fuel assembly in a metal canister, candidate materials for this container need to be studied. 3. It is highly likely that some ''filler'' material will be needed between the fuel elements and the can. 4. Leachability, stability, and waste-rock interaction studies should be carried out on the fuels. The major disadvantages of spent fuel as a disposal form are the lower maximum heat loading, 60 kW/acre versus 150 kW/acre for high-level waste from a reprocessing plant; the greater long-term potential hazard due to the larger quantities of plutonium and uranium introduced into a repository; and the possibility of criticality in case the repository is breached. The major advantages are the lower cost and increased near-term safety resulting from eliminating reprocessing and the treatment and handling of the wastes therefrom

1. The application of PIE techniques to the study of the corrosion of spent oxide fuel in deep-rock groundwaters. 2. Spent fuel degradation

International Nuclear Information System (INIS)

Forsyth, R.S.

1991-01-01

During the autumn of 1990, papers summarizing work performed at Studsvik as part of the SKB research programme designed to study the corrosion behaviour of spent nuclear fuel in deep-rock groundwater were presented at two scientific meetings: The first paper presents results and observations of the study of the corrosion of spent oxide fuel in deep-rock ground-waters. The PIE techniques were applied to the detailed study of spent fuel both before and after water contact. The second paper represents an up-dated reporting of results obtained in the Swedish programme relevant to preferential dissolution effects, including interim results from recently stored experiments specifically designed to study possible correlations between corrosion behaviour and fuel properties conditioned by burnup and/or local power variations. Recent observations during the search for corrosion sites in fuel exposed to corrosion for about 4 years are also presented. (KAE)

Spent nuclear fuel storage

International Nuclear Information System (INIS)

Romanato, Luiz Sergio

2005-01-01

When a country becomes self-sufficient in part of the nuclear cycle, as production of fuel that will be used in nuclear power plants for energy generation, it is necessary to pay attention for the best method of storing the spent fuel. Temporary storage of spent nuclear fuel is a necessary practice and is applied nowadays all over the world, so much in countries that have not been defined their plan for a definitive repository, as well for those that already put in practice such storage form. There are two main aspects that involve the spent fuels: one regarding the spent nuclear fuel storage intended to reprocessing and the other in which the spent fuel will be sent for final deposition when the definitive place is defined, correctly located, appropriately characterized as to several technical aspects, and licentiate. This last aspect can involve decades of studies because of the technical and normative definitions at a given country. In Brazil, the interest is linked with the storage of spent fuels that will not be reprocessed. This work analyses possible types of storage, the international panorama and a proposal for future construction of a spent nuclear fuel temporary storage place in the country. (author)

Spent nuclear fuel project design basis capacity study

International Nuclear Information System (INIS)

Cleveland, K.J.

1998-01-01

A parametric study of the Spent Nuclear Fuel Project system capacity is presented. The study was completed using a commercially available software package to develop a summary level model of the major project systems. A base case, reflecting the Fiscal Year 1998 process configuration, is evaluated. Parametric evaluations are also considered, investigating the impact of higher fuel retrieval system productivity and reduced shift operations at the canister storage building on total project duration

Safety Consideration for a Wet Interim Spent Fuel Store at Conceptual Design Stage

International Nuclear Information System (INIS)

Astoux, Marion

2014-01-01

EDF Energy plans to build and operate two UK EPRs at the Hinkley Point C (HPC) site in Somerset, England. Spent fuel from the UK EPRs will need to be managed from the time it is discharged from the reactor until it is ultimately disposed of and this will involve storing the spent fuel for a period in the fuel building and thereafter in a dedicated interim facility until it can be emplaced within the UK Geological Disposal Facility. EDF Energy has proposed that this interim store should be located on the Hinkley Point site which is consistent with UK policy. This Interim Spent Fuel Store (ISFS) will have the capability to store for at least one hundred years the spent fuel arising from the operation of the two EPR units (sixty years operation). Therefore, specificities regarding the lifetime of the facility have to be accounted for its design. The choice of interim storage technology was considered in some depth for the HPC project and wet storage (pool) was selected. The facility is currently at conceptual design stage, although its construction will be part of main site construction phase. Safety functions and safety requirements for this storage facility have been defined, in compliance with WENRA 'Waste and Spent Fuel Storage - Safety Reference Level Report' and IAEA Specific Safety Guide no. 15 'Storage of Spent Nuclear Fuel'. EDF technical know-how, operational feedback on existing storage pools, UK regulatory context and Fukushima experience feedback have also been accounted for. Achievement of the safety functions as passively as reasonably practicable is a key issue for the design, especially in accident situations. Regarding lifetime aspects, ageing management of equipments, optimisation of the refurbishment, climate change, passivity of the facility, and long-term achievement of the safety functions are among the subjects to consider. Adequate Operational Limits and Conditions will also have to be defined, to enable the long-term achievement of the safety

Conceptual design study of a concrete canister spent-fuel storage facility

International Nuclear Information System (INIS)

Lidfors, E.D.; Tabe, T.; Johnson, H.M.

1979-01-01

This report presents a conceptual design study for the interim storage of CANDU spent fuel in concrete canisters. The canisters will be concrete flasks, which contain fuel prepackaged in double steel containment, and will be cooled by natural air convection. This is one of the methods proposed as a potential alternative to water pool storage. A preliminary study of this concept was done by CAFS (Committee Assessing Fuel Storage), and WNRE (Whiteshell Nuclear Research Establishment) is currently conducting a development and demonstration program. This study of a central facility for the storage of all Canadian spent fuel arisings to the year 2000 was completed in 1975. A brief description of the facilities required and the operations involved, a summary of costs, a survey of the monitoring requirements and a prediction of the personnel exposures associated with this method of storing spent fuel are reported here. The estimated total cost of interim storage in cylindrical canisters at a central site is $6.02/kg U (1975 dollars). Approximately half of this cost is incurred in the shipment of fuel from the reactors to the storage facility. (author)

Minority Carrier Lifetime and Photoluminescence Studies of Antimony-Based Superlattices

Science.gov (United States)

Hoglund, Linda; Soibel, Alexander; Ting, David Z.; Khoshakhlagh, Arezou; Hill, Cory J.; Gunapala, Sarath D.

2012-01-01

In this paper, we have used the OMR technique to study the minority carrier lifetimes in three InAs/GaSb-photoluminescence (PL) structures with different number of periods in the absorber: 300, 400 and 600 periods respectively. The feasibility of using a visible 643 nm laser source with short penetration depth for lifetime measurements was studied by comparing the achieved results to measurements performed on the same samples with a 1550 nm IR laser source, which penetrates much deeper into the sample. Despite the differences in excitation wavelengths and penetration depths, the results from both measurements were very similar. This indicates that the diffusion length is long enough to facilitate a homogeneous distribution of excess carriers in the material.

Mining the bulk positron lifetime

International Nuclear Information System (INIS)

Aourag, H.; Guittom, A.

2009-01-01

We introduce a new approach to investigate the bulk positron lifetimes of new systems based on data-mining techniques. Through data mining of bulk positron lifetimes, we demonstrate the ability to predict the positron lifetimes of new semiconductors on the basis of available semiconductor data already studied. Informatics techniques have been applied to bulk positron lifetimes for different tetrahedrally bounded semiconductors in order to discover computational design rules. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Instant release fraction corrosion studies of commercial UO2 BWR spent nuclear fuel

Science.gov (United States)

Martínez-Torrents, Albert; Serrano-Purroy, Daniel; Sureda, Rosa; Casas, Ignasi; de Pablo, Joan

2017-05-01

The instant release fraction of a spent nuclear fuel is a matter of concern in the performance assessment of a deep geological repository since it increases the radiological risk. Corrosion studies of two different spent nuclear fuels were performed using bicarbonate water under oxidizing conditions to study their instant release fraction. From each fuel, cladded segments and powder samples obtained at different radial positions were used. The results were normalised using the specific surface area to permit a comparison between fuels and samples. Different radionuclide dissolution patterns were studied in terms of water contact availability and radial distribution in the spent nuclear fuel. The relationship between the results of this work and morphological parameters like the grain size or irradiation parameters such as the burn-up or the linear power density was studied in order to increase the understanding of the instant release fraction formation.

Spent nuclear fuel storage - Basic concept

International Nuclear Information System (INIS)

Krempel, Ascanio; Santos, Cicero D. Pacifici dos; Sato, Heitor Hitoshi; Magalhaes, Leonardo de

2009-01-01

According to the procedures adopted in others countries in the world, the spent nuclear fuel elements burned to produce electrical energy in the Brazilian Nuclear Power Plant of Angra do Reis, Central Nuclear Almirante Alvaro Alberto - CNAAA will be stored for a long time. Such procedure will allow the next generation to decide how they will handle those materials. In the future, the reprocessing of the nuclear fuel assemblies could be a good solution in order to have additional energy resource and also to decrease the volume of discarded materials. This decision will be done in the future according to the new studies and investigations that are being studied around the world. The present proposal to handle the nuclear spent fuel is to storage it for a long period of time, under institutional control. Therefore, the aim of this paper is to introduce a proposal of a basic concept of spent fuel storage, which involves the construction of a new storage building at site, in order to increase the present storage capacity of spent fuel assemblies in CNAAA installation; the concept of the spent fuel transportation casks that will transfer the spent fuel assemblies from the power plants to the Spent Fuel Complementary Storage Building and later on from this building to the Long Term Intermediate Storage of Spent Fuel; the concept of the spent fuel canister and finally the basic concept of the spent fuel long term storage. (author)

QUALITY AND SHELF LIFE EVALUATION OF NUGGETS PREPARED FROM SPENT DUCK AND SPENT HEN MEAT

Directory of Open Access Journals (Sweden)

Rajesh Kumar

2015-12-01

Full Text Available A study was conducted to compare the quality of nuggets prepared from spent hen and duck meat. The cooked nuggets were analyzed for pH, thiobarbituric acid (TBA, tyrosine value (TV, moisture, fat, protein, total plate count (TPC and sensory evaluations. Nuggets prepared from spent hen meat showed significantly higher (p<0.05 moisture content however pH, fat and protein content were significantly higher (p<0.05 in duck nuggets. TBA values, TVs and (TPC were highest in duck nuggets but were within the acceptable level up to 7th day of refrigerated storage (4±1°C in both types of nuggets. Both nuggets maintain their sensory quality up to 7th day of refrigeration storage but spent hen nuggets were preferred by consumers compared to nuggets prepared from spent duck meat. Result of the study indicated that, despite the comparative differences among these nuggets, spent duck and hen meat could be used for preparation of nutritionally rich and acceptable nuggets.

Containing method for spent fuel and spent fuel containing vessel

International Nuclear Information System (INIS)

Maekawa, Hiromichi; Hanada, Yoshine.

1996-01-01

Upon containing spent fuels, a metal vessel main body and a support spacer having fuel containing holes are provided. The support spacer is disposed in the inside of the metal vessel main body, and spent fuel assemblies are loaded in the fuel containing holes. Then, a lid is welded at the opening of the metal vessel main body to provide a sealing state. In this state, heat released from the spent fuel assemblies is transferred to the wall of the metal vessel main body via the support spacer. Since the support spacer has a greater heat conductivity than gases, heat of the spent fuel assemblies tends to be released to the outside, thereby capable of removing heat of the spent fuel assemblies effectively. In addition, since the surfaces of the spent fuel assemblies are in contact with the inner surface of the fuel containing holes of the support spacer, impact-resistance and earthquake-resistance are ensured, and radiation from the spent fuel assemblies is decayed by passing through the layer of the support spacer. (T.M.)

Burnup simulations and spent fuel characteristics of ZrO{sub 2} based inert matrix fuels

Energy Technology Data Exchange (ETDEWEB)

Schneider, E.A. [Department of Mechanical Engineering, University of Texas, Austin, TX (United States); Deinert, M.R. [Department of Theoretical and Applied Mechanics, Cornell University, Ithaca, NY (United States)]. E-mail: mrd6@cornell.edu; Herring, S.T. [Idaho National Laboratory, Idaho Falls, ID (United States); Cady, K.B. [Department of Theoretical and Applied Mechanics, Cornell University, Ithaca, NY (United States)

2007-03-31

Reducing the inventory of long lived isotopes that are contained in spent nuclear fuel is essential for maximizing repository capacity and extending the lifetime of related storage. Because of their non-fertile matrices, inert matrix fuels (IMF's) could be an ideal vehicle for using light-water reactors to help decrease the inventory of plutonium and other transuranics (neptunium, americium, curium) that are contained within spent uranium oxide fuel (UOX). Quantifying the characteristics of spent IMF is therefore of fundamental importance to determining its effect on repository design and capacity. We consider six ZrO{sub 2} based IMF formulations with different transuranic loadings in a 1-8 IMF to UOX pin-cell arrangement. Burnup calculations are performed using a collision probability model where transport of neutrons through space is modeled using fuel to moderator transport and escape probabilities. The lethargy dependent neutron flux is treated with a high resolution multigroup thermalization method. The results of the reactor physics model are compared to a benchmark case performed with Montebruns and indicate that the approach yields reliable results applicable to high-level analyses of spent fuel isotopics. The data generated show that a fourfold reduction in the radiological and integrated thermal output is achievable in single recycle using IMF, as compared to direct disposal of an energy equivalent spent UOX.

Global Spent Fuel Logistics Systems Study (GSFLS). Volume 4. Pacific basin spent fuel logistics system

International Nuclear Information System (INIS)

1978-06-01

This report summarizes the conceptual framework for a Pacific Basin Spent Fuel Logistics System (PBSFLS); and preliminarily describes programatic steps that might be taken to implement such a system. The PBSFLS concept is described in terms of its technical and institutional components. The preferred PBSFLS concept embodies the rationale of emplacing a fuel cycle system which can adjust to the technical and institutional non-proliferation solutions as they are developed and accepted by nations. The concept is structured on the basis of initially implementing a regional spent fuel storage and transportation system which can technically and institutionally accommodate downstream needs for energy recovery and long-term waste management solutions

Positron lifetime study of electron-irradiated epoxy resins

International Nuclear Information System (INIS)

Suevegh, K.; Vertes, A.; Wojnarovits, L.; Foeldiak, G.; Liszkai, L.; Kajcsos, Zs.

1990-01-01

Two bisphenol-A type epoxy resins were irradiated by electron beam and studied afterwards by positron lifetime spectroscopy. An interesting result is that despite of the considerable amount of free-radicals, no inhibition of positronium formation was observed in the two epoxies. Nevertheless, several serious differences were detected between the studied polymers. The results suggest that the radiation-resistant properties of epoxies depend strongly on the amount of the curing agent. (author) 8 refs.; 2 figs

Phenomenological description reference concept (Spent Fuel - Copper - Iron - Bentonite - Granite)

International Nuclear Information System (INIS)

Lehikoinen, J.; Nordman, H.

2008-12-01

This report gives a broad overview of the salient processes and associated time frames and uncertainties pertaining to the long-term normal evolution of the near-field of a deep repository of the KBS-3V type. By normal evolution, reference is made to the description of the evolution of a disposal system subject to the assumption that all the spent fuel canisters remain intact following emplacement and repository closure for at least the design corrosion lifetime of the canister overpack in the expected repository conditions. In this connection, the effects of future glaciations, canister manufacturing defects and small-scale tectonic activity are briefly touched upon. The roles of the different repository near-field barriers in providing safety are briefly noted. The description of the normal evolution of a KBS-3V-type repository near-field conditions external to the unbreached spent fuel canister has been realized in terms of processes rather than timescales. Separate chapters have been devoted to the thermal, hydraulic, mechanical and chemical/biological evolution of the repository system, with due attention to some of the couplings between them. (orig.)

Assessment of spent fuel cooling

International Nuclear Information System (INIS)

Ibarra, J.G.; Jones, W.R.; Lanik, G.F.

1997-01-01

The paper presents the methodology, the findings, and the conclusions of a study that was done by the Nuclear Regulatory Commission's Office for Analysis and Evaluation of Operational Data (AEOD) on loss of spent fuel pool cooling. The study involved an examination of spent fuel pool designs, operating experience, operating practices, and procedures. AEOD's work was augmented in the area of statistics and probabilistic risk assessment by experts from the Idaho Nuclear Engineering Laboratory. Operating experience was integrated into a probabilistic risk assessment to gain insight on the risks from spent fuel pools

Nuclear lifetimes

International Nuclear Information System (INIS)

Caraca, J.M.G.

1976-01-01

The importance of the results obtained in experiments of measurement of lifetimes for a detailed knowledge of nuclear structure is referred. Direct methods of measurement of nuclear lifetimes are described, namely, electronic methods, recoil-distance method, doppler shift atenuation method and blocking-method. A brief reference is made to indirect methods for measurement of life-times

Temperature and time dependence of free volume in bisphenol A polycarbonate studied by positron lifetime spectroscopy

NARCIS (Netherlands)

Kluin, J.E.; Yu, Z.; Vleeshouwers, S.M.; McGervey, J.D.; Jamieson, A.M.; Simha, R.

1992-01-01

New positron lifetime expts. were carried out for Bisphenol-A polycarbonate. The influence of unavoidable pos. charged positron irradn. on the lifetime and intensity of o-positronium (o-Ps) annihilation was studied. Results obtained using a state-of-the-art lifetime spectrometer (count rate 670 cps

Three-dimensional fluorescence lifetime tomography

International Nuclear Information System (INIS)

Godavarty, Anuradha; Sevick-Muraca, Eva M.; Eppstein, Margaret J.

2005-01-01

Near-infrared fluorescence tomography using molecularly targeted lifetime-sensitive, fluorescent contrast agents have applications for early-stage cancer diagnostics. Yet, although the measurement of fluorescent lifetime imaging microscopy (FLIM) is extensively used in microscopy and spectroscopy applications, demonstration of fluorescence lifetime tomography for medical imaging is limited to two-dimensional studies. Herein, the feasibility of three-dimensional fluorescence-lifetime tomography on clinically relevant phantom volumes is established, using (i) a gain-modulated intensified charge coupled device (CCD) and modulated laser diode imaging system, (ii) two fluorescent contrast agents, e.g., Indocyanine green and 3-3'-Diethylthiatricarbocyanine iodide differing in their fluorescence lifetime by 0.62 ns, and (iii) a two stage approximate extended Kalman filter reconstruction algorithm. Fluorescence measurements of phase and amplitude were acquired on the phantom surface under different target to background fluorescence absorption (70:1, 100:1) and fluorescence lifetime (1:1, 2.1:1) contrasts at target depths of 1.4-2 cm. The Bayesian tomography algorithm was employed to obtain three-dimensional images of lifetime and absorption owing to the fluorophores

Spent Fuel in Chile

International Nuclear Information System (INIS)

López Lizana, F.

2015-01-01

The government has made a complete and serious study of many different aspects and possible road maps for nuclear electric power with strong emphasis on safety and energy independence. In the study, the chapter of SFM has not been a relevant issue at this early stage due to the fact that it has been left for later implementation stage. This paper deals with the options Chile might consider in managing its Spent Fuel taking into account foreign experience and factors related to safety, economics, public acceptance and possible novel approaches in spent fuel treatment. The country’s distinctiveness and past experience in this area taking into account that Chile has two research reactors which will have an influence in the design of the Spent Fuel option. (author)

A study for providing additional storage spaces to ET-RR-1 spent fuel

International Nuclear Information System (INIS)

El-Kady, A.; Ashoub, N.; Saleh, H.G.

1995-01-01

The ET-RR-1 reactor spent fuel storage pool is a trapezoidal aluminum tank concrete shield and of capacity 10 m 3 . It can hold up to 60 fuel assemblies. The long operation history of the ET-RR-1 reactor resulted in a partially filled spent fuel storage with the remaining spaces not enough to host a complete load from the reactor. This work have been initiated to evaluate possible alternative solutions for providing additional storage spaces to host the available EK-10 fuel elements after irradiation and any foreseen fuel in case of reactor upgrading. Several alternate solutions have been reviewed and decision on the most suitable one is under study. These studies include criticality calculation of some suggested alternatives like reracking the present spent fuel storage pool and double tiering by the addition of a second level storage rack above the existing rack. The two levels may have different factor. Criticality calculation of the double tiering possible accident was also studied. (author)

Validity of LIDAS (LIfetime Depression Assessment Self-report): a self-report online assessment of lifetime major depressive disorder.

Science.gov (United States)

Bot, M; Middeldorp, C M; de Geus, E J C; Lau, H M; Sinke, M; van Nieuwenhuizen, B; Smit, J H; Boomsma, D I; Penninx, B W J H

2017-01-01

There is a paucity of valid, brief instruments for the assessment of lifetime major depressive disorder (MDD) that can be used in, for example, large-scale genomics, imaging or biomarker studies on depression. We developed the LIfetime Depression Assessment Self-report (LIDAS), which assesses lifetime MDD diagnosis according to DSM criteria, and is largely based on the widely used Composite International Diagnostic Interview (CIDI). Here, we tested the feasibility and determined the sensitivity and specificity for measuring lifetime MDD with this new questionnaire, with a regular CIDI as reference. Sensitivity and specificity analyses of the online lifetime MDD questionnaire were performed in adults with (n = 177) and without (n = 87) lifetime MDD according to regular index CIDIs, selected from the Netherlands Study of Depression and Anxiety (NESDA) and Netherlands Twin Register (NTR). Feasibility was tested in an additional non-selective, population-based sample of NTR participants (n = 245). Of the 753 invited persons, 509 (68%) completed the LIDAS, of which 419 (82%) did this online. User-friendliness of the instrument was rated high. Median completion time was 6.2 min. Sensitivity and specificity for lifetime MDD were 85% [95% confidence interval (CI) 80-91%] and 80% (95% CI 72-89%), respectively. This LIDAS instrument gave a lifetime MDD prevalence of 20.8% in the population-based sample. Measuring lifetime MDD with an online instrument was feasible. Sensitivity and specificity were adequate. The instrument gave a prevalence of lifetime MDD in line with reported population prevalences. LIDAS is a promising tool for rapid determination of lifetime MDD status in large samples, such as needed for genomics studies.

Positron annihilation lifetime spectroscopy source correction determination: A simulation study

Energy Technology Data Exchange (ETDEWEB)

Kanda, Gurmeet S.; Keeble, David J., E-mail: d.j.keeble@dundee.ac.uk

2016-02-01

Positron annihilation lifetime spectroscopy (PALS) can provide sensitive detection and identification of vacancy-related point defects in materials. These measurements are normally performed using a positron source supported, and enclosed by, a thin foil. Annihilation events from this source arrangement must be quantified and are normally subtracted from the spectrum before analysis of the material lifetime components proceeds. Here simulated PALS spectra reproducing source correction evaluation experiments have been systematically fitted and analysed using the packages PALSfit and MELT. Simulations were performed assuming a single lifetime material, and for a material with two lifetime components. Source correction terms representing a directly deposited source and various foil supported sources were added. It is shown that in principle these source terms can be extracted from suitably designed experiments, but that fitting a number of independent, nominally identical, spectra is recommended.

Positron lifetime study of the devitrification process in a cordierite glass

International Nuclear Information System (INIS)

Pedrosa, M.A.; Pareja, R.

1985-01-01

The devitrification of the 13.3% MgO-32.0% Al 2 O 3 -52.7% SiO 2 -2.0% BaO ceramic-glass via isochronal heating up to a stable crystalline structure has been studied by the positron annihilation technique. The lifetime spectra showed two components. This devitrification results as a two-stage process. The long-lifetime tau 2 , attributed to the pick-off annihilation of ortho-Ps states, decreased on crystallization, but it was insensitive to the hexagonal-orthorhombic transformation of the crystalline cordierite. On the contrary, the effective lifetime of positrons annihilating in states that are not Ps, increased. This increase has been attributed to the Al/Si order process inherent to the hexagonal-orthorhombic transformation. Moreover, the Ps fraction in the crystalline phases was higher than in the glassy phase. However the free volume model might qualitatively explain the relationship observed between I 2 and tau 2 . (author)

HFIR spent fuel management alternatives

International Nuclear Information System (INIS)

Begovich, J.M.; Green, V.M.; Shappert, L.B.; Lotts, A.L.

1992-01-01

The High Flux Isotope Reactor (HFIR) at Martin Marietta Energy Systems' Oak Ridge National Laboratory (ORNL) has been unable to ship its spent fuel to Savannah River Site (SRS) for reprocessing since 1985. The HFIR storage pools are expected to fill up in the February 1994 to February 1995 time frame. If a management altemative to existing HFIR pool storage is not identified and implemented before the HFIR pools are full, the HFIR will be forced to shut down. This study investigated several alternatives for managing the HFIR spent fuel, attempting to identify options that could be implemented before the HFIR pools are full. The options investigated were: installing a dedicated dry cask storage facility at ORNL, increasing HFIR pool storage capacity by clearing the HFIR pools of debris and either close-packing or stacking the spent fuel elements, storing the spent fuel at another ORNL pool, storing the spent fuel in one or more hot cells at ORNL, and shipping the spent fuel offsite for reprocessing or storage elsewhere

Anaerobic treatment of distillery spent wash - a study on upflow anaerobic fixed film bioreactor.

Science.gov (United States)

Acharya, Bhavik K; Mohana, Sarayu; Madamwar, Datta

2008-07-01

Anaerobic digestion of wastewater from a distillery industry having very high COD (1,10,000-1,90,000 mg/L) and BOD (50,000-60,000 mg/L) was studied in a continuously fed, up flow fixed film column reactor using different support materials such as charcoal, coconut coir and nylon fibers under varying hydraulic retention time and organic loading rates. The seed consortium was prepared by enrichment with distillery spent wash in a conventional type reactor having working capacity of 3 L and was used for charging the anaerobic column reactor. Amongst the various support materials studied the reactor having coconut coir could treat distillery spent wash at 8d hydraulic retention time with organic loading rate of 23.25 kg COD m(-3)d(-1) leading to 64% COD reduction with biogas production of 7.2 m3 m(-3)d(-1) having high methane yield without any pretreatment or neutralization of the distillery spent wash. This study indicates fixed film biomethanation of distillery spent wash using coconut coir as the support material appears to be a cost effective and promising technology for mitigating the problems caused by distillery effluent.

Probable leaching mechanisms for spent fuel

International Nuclear Information System (INIS)

Wang, R.; Katayama, Y.B.

1981-01-01

At the Pacific Northwest Laboratory, researchers in the Waste/Rock Interaction Technology Program are studying spent fuel as a possible waste form for the Office of Nuclear Waste Isolation. This paper presents probable leaching mechanisms for spent fuel and discusses current progress in identifying and understanding the leaching process. During the past year, experiments were begun to study the complex leaching mechanism of spent fuel. The initial work in this investigation was done with UO 2 , which provided the most information possible on the behavior of the spent-fuel matrix without encountering the very high radiation levels associated with spent fuel. Both single-crystal and polycrystalline UO 2 samples were used for this study, and techniques applicable to remote experimentation in a hot cell are being developed. The effects of radiation are being studied in terms of radiolysis of water and surface activation of the UO 2 . Dissolution behavior and kinetics of UO 2 were also investigated by electrochemical measurement techniques. These data will be correlated with those acquired when spent fuel is tested in a hot cell. Oxidation effects represent a major area of concern in evaluating the stability of spent fuel. Dissolution of UO 2 is greatly increased in an oxidizing solution because the dissolution is then controlled by the formation of hexavalent uranium. In solutions containing very low oxygen levels (i.e., reducing solutions), oxidation-induced dissolution may be possible via a previously oxidized surface, through exposure to air during storage, or by local oxidants such as O 2 and H 2 O 2 produced from radiolysis of water and radiation-activated UO 2 surfaces. The effects of oxidation not only increase the dissolution rate, but could lead to the disintegration of spent fuel into fine fragments

Ceramic pot filters lifetime study in coastal Guatemala.

Science.gov (United States)

Salvinelli, C; Elmore, A C; García Hernandez, B R; Drake, K D

2017-02-01

Ceramic pot filters (CPFs) are an effective means of household water treatment, but the characterization of CPF lifetimes is ongoing. This paper describes a lifetime field study in Guatemala which was made possible by a collaboration between researchers, CPF-using households, and local non-governmental organizations (NGOs). Disinfection data were collected periodically for two years using field coliform enumeration kits as were flow rate data with the assistance of NGO staff. Consumer acceptance was characterized by surveying householders in the four subject villages at the beginning and end of the study. Flow rate data showed that average CPF flow rates decreased below the recommended minimum of 1 L h -1 after 10 months of use; however, the survey results indicated that the consumers were tolerant of the lower flow rates, and it is reasonable to assume that the daily volume of treated water can be readily increased by refilling the CPFs more frequently. Of greater concern was the finding that disinfection efficacy decreased below the recommended bacterial reduction after 14 months of use because it would not be obvious to users that effectiveness had declined. Finally, the follow-up visits by the researchers and the NGO staff appeared to increase consumer acceptance of the CPFs.

A positron annihilation lifetime spectroscopy study of porous silicon using a continuous lifetime fitting algorithm

International Nuclear Information System (INIS)

Derlet, P.M.; Choy, T.C.

1996-01-01

In the present work we report on a positron annihilation lifetime spectroscopy (PALS) investigation of porous silicon using a continuous lifetime fitting algorithm. Our motivation lies in the underlying disadvantage in discrete lifetime fitting algorithms where the number of components must initially be assumed since in general a realistic spectrum does not uniquely determine this number. This becomes particularly apparent when looking at highly disordered systems where the notion of a discrete spectrum may be invalid and indeed crucial to an understanding of the optical absorption and photo-luminescence properties. Using the PALS data collected from different porous silicon samples in conjunction with other methods of characterisation, we have extended the findings of previous work. In particular we resolve three rather than two ortho-positronium components, suggesting that there may be an additional intermediary scale of porosity in which ortho-positronium annihilates. We also establish the existence of a very weak ortho-positronium component in the pre-anodised wafers at a time scale approximately equal to the longest time ortho-positronium component seen in porous silicon, suggesting that irregularities of a particular magnitude exist before anodisation and that these may, in part, be the catalyst for the initial pore formation process

Studies and research concerning BNFP: LWR spent fuel storage

International Nuclear Information System (INIS)

Shallo, F.A.

1978-08-01

This report describes potential spent fuel storage expansion programs using the Barnwell Nuclear Fuel Plant--Fuel Receiving and Storage Station (BNFP-FRSS) as a model. Three basic storage arrangements are evaluated with cost and schedule estimates being provided for each configuration. A general description of the existing facility is included with emphasis on the technical and equipment requirements which would be necessary to achieve increased spent fuel storage capacity at BNFP-FRSS

Instant release fraction corrosion studies of commercial UO{sub 2} BWR spent nuclear fuel

Energy Technology Data Exchange (ETDEWEB)

Martínez-Torrents, Albert, E-mail: albert.martinez@ctm.com.es [Fundació CTM Centre Tecnològic, Plaça de la Ciència 2, 08243 Manresa (Spain); Serrano-Purroy, Daniel [European Commission, DG Joint Research Centre - JRC, Directorate G - Nuclear Safety & Security, Department G.III, P.O. Box 2340, D-76125 Karlsruhe (Germany); Sureda, Rosa [Fundació CTM Centre Tecnològic, Plaça de la Ciència 2, 08243 Manresa (Spain); Casas, Ignasi [Department of Chemical Engineering, Universitat Politècnica de Catalunya – Barcelona Tech, Eduard Maristany 14, 08019 Barcelona (Spain); Pablo, Joan de [Fundació CTM Centre Tecnològic, Plaça de la Ciència 2, 08243 Manresa (Spain); Department of Chemical Engineering, Universitat Politècnica de Catalunya – Barcelona Tech, Eduard Maristany 14, 08019 Barcelona (Spain)

2017-05-15

The instant release fraction of a spent nuclear fuel is a matter of concern in the performance assessment of a deep geological repository since it increases the radiological risk. Corrosion studies of two different spent nuclear fuels were performed using bicarbonate water under oxidizing conditions to study their instant release fraction. From each fuel, cladded segments and powder samples obtained at different radial positions were used. The results were normalised using the specific surface area to permit a comparison between fuels and samples. Different radionuclide dissolution patterns were studied in terms of water contact availability and radial distribution in the spent nuclear fuel. The relationship between the results of this work and morphological parameters like the grain size or irradiation parameters such as the burn-up or the linear power density was studied in order to increase the understanding of the instant release fraction formation.

ASSESSMENT OF MICROBIAL LOAD OF SAUSAGES PREPARED FROM DIFFERENT COMBINATION OF SPENT DUCK AND SPENT HEN MEAT

Directory of Open Access Journals (Sweden)

Rajesh Kumar

2016-12-01

Full Text Available Aim of the present study was to assess the microbial load of sausages prepared from different combination of spent duck and spent hen meat. The combination are 100% spent duck (T1, 75%+ 25% spent duck and spent hen (T2, 50%+50% spent duck and spent hen (T3, 25%+75% spent duck and spent hen (T4 and 100% spent hen (T5. All the samples of different combination were subjected to total plate count (TPC, total psychrophilic count (TPSC and total Coliform count (TCC. Mean of TPC for T1, T2, T3, T4 and T5 were 4.69, 4.62, 4.60, 4.49 and 4.46 log 10 CFU/gm respectively, while mean TPSC were 4.46, 4.46, 4.43, 4.36 and 4.36 log CFU/gm respectively There were no significant (p<0.05 difference between the different group of combination of sausages for TPS as well as TPSC but varies significantly (p<0.05 from 14th day of storage in both cases. The coliform group of bacteria will not be detected in any combination of sausages. It is concluded that microbial load of sausage prepared from spent duck is high and it is decreases as the percentage of duck meat decreases but, the upper limit of bacteria in each group of sausages is within limit and hence it is safe for human consumption.

Lifetime measurements

International Nuclear Information System (INIS)

Fossan, D.B.; Warburton, E.K.

1974-01-01

Lifetime measurements are discussed, concentrating on the electronic technique, the recoil distance method (RDM), and the Doppler shift attenuation method (DSAM). A brief review of several indirect timing techniques is given, and their specific advantages and applicability are considered. The relationship between lifetimes of nuclear states and the nuclear structure information obtained from them is examined. A short discussion of channeling and microwave methods of lifetime measurement is presented. (23 figures, 171 references) (U.S.)

Spent fuel storage process equipment development

International Nuclear Information System (INIS)

Park, Hyun Soo; Lee, Jae Sol; Yoo, Jae Hyung

1990-02-01

Nuclear energy which is a major energy source of national energy supply entails spent fuels. Spent fuels which are high level radioactive meterials, are tricky to manage and need high technology. The objectives of this study are to establish and develop key elements of spent fuel management technologies: handling equipment and maintenance, process automation technology, colling system, and cleanup system. (author)

Studies and research concerning BNFP: spent fuel dry storage studies at the Barnwell Nuclear Fuel Plant

International Nuclear Information System (INIS)

Anderson, K.J.

1980-09-01

Conceptual designs are presented utilizing the Barnwell Nuclear Fuel Plant for the dry interim storage of spent light water reactor fuel. Studies were conducted to determine feasible approaches to storing spent fuel by methods other than wet pool storage. Fuel that has had an opportunity to cool for several years, or more, after discharge from a reactor is especially adaptable to dry storage since its thermal load is greatly reduced compared to the thermal load immediately following discharge. A thermal analysis was performed to help in determining the feasibility of various spent fuel dry storage concepts. Methods to reject the heat from dry storage are briefly discussed, which include both active and passive cooling systems. The storage modes reviewed include above and below ground caisson-type storage facilities and numerous variations of vault, or hot cell-type, storage facilities

Quantitative analysis of fluorescence lifetime measurements of the macula using the fluorescence lifetime imaging ophthalmoscope in healthy subjects.

Science.gov (United States)

Dysli, Chantal; Quellec, Gwénolé; Abegg, Mathias; Menke, Marcel N; Wolf-Schnurrbusch, Ute; Kowal, Jens; Blatz, Johannes; La Schiazza, Olivier; Leichtle, Alexander B; Wolf, Sebastian; Zinkernagel, Martin S

2014-04-03

Fundus autofluorescence (FAF) cannot only be characterized by the intensity or the emission spectrum, but also by its lifetime. As the lifetime of a fluorescent molecule is sensitive to its local microenvironment, this technique may provide more information than fundus autofluorescence imaging. We report here the characteristics and repeatability of FAF lifetime measurements of the human macula using a new fluorescence lifetime imaging ophthalmoscope (FLIO). A total of 31 healthy phakic subjects were included in this study with an age range from 22 to 61 years. For image acquisition, a fluorescence lifetime ophthalmoscope based on a Heidelberg Engineering Spectralis system was used. Fluorescence lifetime maps of the retina were recorded in a short- (498-560 nm) and a long- (560-720 nm) spectral channel. For quantification of fluorescence lifetimes a standard ETDRS grid was used. Mean fluorescence lifetimes were shortest in the fovea, with 208 picoseconds for the short-spectral channel and 239 picoseconds for the long-spectral channel, respectively. Fluorescence lifetimes increased from the central area to the outer ring of the ETDRS grid. The test-retest reliability of FLIO was very high for all ETDRS areas (Spearman's ρ = 0.80 for the short- and 0.97 for the long-spectral channel, P macula in healthy subjects. By using a custom-built software, we were able to quantify fluorescence lifetimes within the ETDRS grid. Establishing a clinically accessible standard against which to measure FAF lifetimes within the retina is a prerequisite for future studies in retinal disease.

A Preliminary Study on the Reuse of the Recovered Uranium from the Spent CANDU Fuel Using Pyroprocessing

International Nuclear Information System (INIS)

Park, C. J.; Na, S. H.; Yang, J. H.; Kang, K. H.; Lee, J. W.

2009-01-01

During the pyroprocessing, most of the uranium is gathered in metallic form around a solid cathode during an electro-refining process, which is composed of about 94 weight percent of the spent fuel. In the previous study, a feasibility study has been done to reuse the recovered uranium for the CANDU reactor fuel following the traditional DUPIC (direct use of spent pressurized water reactor fuel into CANDU reactor) fuel fabrication process. However, the weight percent of U-235 in the recovered uranium is about 1 wt% and it is sufficiently re-utilized in a heavy water reactor which uses a natural uranium fuel. The reuse of recovered uranium will bring not only a huge economic profit and saving of uranium resources but also an alleviation of the burden on the management and the disposal of the spent fuel. The research on recycling of recovered uranium was carried out 10 years ago and most of the recovered uranium was assumed to be imported from abroad at that time. The preliminary results showed there is the sufficient possibility to recycle recovered uranium in terms of a reactor's characteristics as well as the fuel performance. However, the spent CANDU fuel is another issue in the storage and disposal problem. At present, most countries are considering that the spent CANDU fuel is disposed directly due to the low enrichment (∼0.5 wt%) of the discharge fissile content and lots of fission products. If mixing the spent CANDU fuel and the spent PWR fuel, the estimated uranium fissile enrichment will be about 0.6 wt% ∼ 1.0 wt% depending on the mixing ratio, which is sufficiently reusable in a CANDU reactor. Therefore, this paper deals with a feasibility study on the recovered uranium of the mixed spent fuel from the pyroprocessing. With the various mixing ratios between the PWR spent fuel and the CANDU spent fuel, a reactor characteristics including the safety parameters of the CANDU reactor was evaluated

Federal interim storage fee study for civilian spent nuclear fuel: a technical and economical analysis

International Nuclear Information System (INIS)

1983-07-01

This report describes the study conducted by the Department of Energy (the Department) regarding payment charges for the federal interim storage (FIS) of spent fuel and presents the details of the study results. It describes the selection of a methodology for calculating a FIS fee schedule, sets forth the estimates of cost for construction and operation of FIS facilities, provides a range of estimates for the fee for FIS services, and identifies special contractual considerations associated with providing FIS services to authorized users. The fee is structured for a range of spent fuel capacities because of uncertainties regarding the schedule of availability and amount of spent fuel that may require and qualify for FIS. The results set forth in the report were used as a basis for development of the report entitled Payment Charges for Federal Interim Storage of Spent Nuclear Fuel from Civilian Nuclear Power Plants in the United States, dated July 1983

Spent fuel characterization for the commercial waste and spent fuel packaging program

International Nuclear Information System (INIS)

Fish, R.L.; Davis, R.B.; Pasupathi, V.; Klingensmith, R.W.

1980-03-01

This document presents the rationale for spent fuel characterization and provides a detailed description of the characterization examinations. Pretest characterization examinations provide quantitative and qualitative descriptions of spent fuel assemblies and rods in their irradiated conditions prior to disposal testing. This information is essential in evaluating any subsequent changes that occur during disposal demonstration and laboratory tests. Interim examinations and post-test characterization will be used to identify fuel rod degradation mechanisms and quantify degradation kinetics. The nature and behavior of the spent fuel degradation will be defined in terms of mathematical rate equations from these and laboratory tests and incorporated into a spent fuel performance prediction model. Thus, spent fuel characterization is an essential activity in the development of a performance model to be used in evaluating the ability of spent fuel to meet specific waste acceptance criteria and in evaluating incentives for modification of the spent fuel assemblies for long-term disposal purposes

Spent fuel treatment in Japan

International Nuclear Information System (INIS)

Takahashi, K.

1999-01-01

In Japan, 52 nuclear power reactors are operating with a total power generation capacity of 45 GWe. The cumulative amount of spent fuel arising, as of March 1998, is about 14,700 W. Spent fuel is reprocessed and recovered nuclear materials are to be recycled in LWRs and FBRs. Pu utilization in LWRs will commence in 1999. In January 1997, short-term policy measures were announced by the Atomic Energy Commission, which addressed promotion of the reprocessing programme in Rokkasho, plutonium utilization in LWRs, spent fuel management, back-end measures and FBR development. With regard to the spent fuel management, the policy measures included expansion of spent fuel storage capacity at reactor sites and a study on spent fuel storage away-from-reactor sites, considering the increasing amount of spent fuel arising. Valuable experience was been accumulated at the Tokai Reprocessing Plant (TRP), from the start of hot operation in 1977 up to now. The role of the TRP will be changed from an operation-oriented to a more R and D oriented facility, when PNC is reorganized into the new organization JNC. The Rokkasho reprocessing plant is under construction and is expected to commence operation in 2003. R and D of future recycling technologies is also continued for the establishment of a nuclear fuel cycle based on FBRs and LWRs. (author)

Lifetime risk of developing coronary heart disease in Aboriginal Australians: a cohort study.

Science.gov (United States)

Wang, Zhiqiang; Hoy, Wendy E

2013-01-30

Lifetime risk of coronary heart disease (CHD) is an important yardstick by which policy makers, clinicians and the general public can assess and promote the awareness and prevention of CHD. The lifetime risk in Aboriginal people is not known. Using a cohort with up to 20 years of follow-up, we estimated the lifetime risk of CHD in Aboriginal people. A cohort study. A remote Aboriginal region. 1115 Aboriginal people from one remote tribal group who were free from CHD at baseline were followed for up to 20 years. During the follow-up period, new CHD incident cases were identified through hospital and death records. We estimated the lifetime risks of CHD with and without adjusting for the presence of competing risk of death from non-CHD causes. Participants were followed up for 17 126 person-years, during which 185 developed CHD and 144 died from non-CHD causes. The average age at which the first CHD event occurred was 48 years for men and 49 years for women. The risk of developing CHD increased with age until 60 years and then decreased with age. Lifetime cumulative risk without adjusting for competing risk was 70.7% for men and 63.8% for women. Adjusting for the presence of competing risk of death from non-CHD causes, the lifetime risk of CHD was 52.6% for men and 49.2% for women. Lifetime risk of CHD is as high as one in two in both Aboriginal men and women. The average age of having first CHD events was under 50 years, much younger than that reported in non-Aboriginal populations. Our data provide useful knowledge for health education, screening and prevention of CHD in Aboriginal people.

Use of Groundwater Lifetime Expectancy for the Performance Assessment of Deep Geologic Radioactive Waste Repositories.

Science.gov (United States)

Cornaton, F.; Park, Y.; Normani, S.; Sudicky, E.; Sykes, J.

2005-12-01

Long-term solutions for the disposal of toxic wastes usually involve isolation of the wastes in a deep subsurface geologic environment. In the case of spent nuclear fuel, the safety of the host repository depends on two main barriers: the engineered barrier and the natural geological barrier. If radionuclide leakage occurs from the engineered barrier, the geological medium represents the ultimate barrier that is relied upon to ensure safety. Consequently, an evaluation of radionuclide travel times from the repository to the biosphere is critically important in a performance assessment analysis. In this study, we develop a travel time framework based on the concept of groundwater lifetime expectancy as a safety indicator. Lifetime expectancy characterizes the time radionuclides will spend in the subsurface after their release from the repository and prior to discharging into the biosphere. The probability density function of lifetime expectancy is computed throughout the host rock by solving the backward-in-time solute transport equation subject to a properly posed set of boundary conditions. It can then be used to define optimal repository locations. In a second step, the risk associated with selected sites can be evaluated by simulating an appropriate contaminant release history. The proposed methodology is applied in the context of a typical Canadian Shield environment. Based on a statistically-generated three-dimension network of fracture zones embedded in the granitic host rock, the sensitivity and the uncertainty of lifetime expectancy to the hydraulic and dispersive properties of the fracture network, including the impact of conditioning via their surface expressions, is computed in order to demonstrate the utility of the methodology.

Continuous amorphization of Cu-Zr studied by positron lifetime

International Nuclear Information System (INIS)

Wilde, G.; Wuerschum, R.; Rabitsch, H.; Puff, W.

2006-01-01

Full text: Solid state amorphization by cold-rolling represents an attractive alternative to commonly used ball-milling. The present work aimed at a free volume study of the process of amorphization. To study the amorphization process binary Cu-Zr alloys were mechanically intermixed by cold rolling. Foils of pure Cu and Zr were stacked to form arrays of composition Cu 60 Zr 40 and folded four times. The folded samples were rolled at a strain rate of approximately 0.1 s -1 to a thickness of about 80 μm and then folded to double the thickness and rolled again to a minimum thickness of 80 μm. This procedure was repeated until the final material was cold-rolled for up to 80 passes. The microstructural changes during cold-rolling were investigated at different stages of the mechanical intermixing process by positron lifetime and 2-dimensional Doppler broadening measurements. The obtained Doppler results are discussed analysing the S-W-plot as well as a two-component fit and the shape of the ratio curves. Finally the results are compared to the lifetime results. (author)

Global spent fuel logistics systems study (GSFLS). Volume I. GSFLS summary report

Energy Technology Data Exchange (ETDEWEB)

None

1978-06-01

An important element in the implementation of international nuclear energy policies is the creation of viable systems for transporting, handling, storing, and disposing of the world's spent nuclear fuel. There is an urgent need to implement selected global spent fuel logistics systems (GSFLS) which can best bridge the interests of countries throughout the world and provide the necessary means for transporting, handling, storing and disposing of spent nuclear fuel. The viability of these systems depends upon their compatibility with governmental policies and nonproliferation concerns; their adequacy in support of projected global nuclear power programs; and their adaptation to realistic technological and institutional constraints. The United States Department of Energy contracted with Boeing Engineering and Construction (BEC), a division of the Boeing Company, and its subcontractors, International Energy Associates Limited (IEAL) and the firm of Doub, Purcell, Muntzing and Hansen to conduct a study of issues and options in establishing GSFLS and to develop preliminary GSFLS concepts. BEC conducted the study integration and developed the technological/economic framework; IEAL researched and developed the institutional framework; and the firm of Doub, Purcell, Muntzing and Hansen conducted the legal/regulatory research associated with the study. BEC also consulted with the First Boston Corporation regarding generic financial considerations associated with GSFLS. This report provides a summarization of the GSFLS study findings.

Global spent fuel logistics systems study (GSFLS). Volume I. GSFLS summary report

International Nuclear Information System (INIS)

1978-06-01

An important element in the implementation of international nuclear energy policies is the creation of viable systems for transporting, handling, storing, and disposing of the world's spent nuclear fuel. There is an urgent need to implement selected global spent fuel logistics systems (GSFLS) which can best bridge the interests of countries throughout the world and provide the necessary means for transporting, handling, storing and disposing of spent nuclear fuel. The viability of these systems depends upon their compatibility with governmental policies and nonproliferation concerns; their adequacy in support of projected global nuclear power programs; and their adaptation to realistic technological and institutional constraints. The United States Department of Energy contracted with Boeing Engineering and Construction (BEC), a division of the Boeing Company, and its subcontractors, International Energy Associates Limited (IEAL) and the firm of Doub, Purcell, Muntzing and Hansen to conduct a study of issues and options in establishing GSFLS and to develop preliminary GSFLS concepts. BEC conducted the study integration and developed the technological/economic framework; IEAL researched and developed the institutional framework; and the firm of Doub, Purcell, Muntzing and Hansen conducted the legal/regulatory research associated with the study. BEC also consulted with the First Boston Corporation regarding generic financial considerations associated with GSFLS. This report provides a summarization of the GSFLS study findings

Defect study of Zn-doped p-type gallium antimonide using positron lifetime spectroscopy

International Nuclear Information System (INIS)

Ling, C. C.; Fung, S.; Beling, C. D.; Huimin, Weng

2001-01-01

Defects in p-type Zn-doped liquid-encapsulated Czochralski--grown GaSb were studied by the positron lifetime technique. The lifetime measurements were performed on the as-grown sample at temperature varying from 15 K to 297 K. A positron trapping center having a characteristic lifetime of 317 ps was identified as the neutral V Ga -related defect. Its concentration in the as-grown sample was found to be in the range of 10 17 --10 18 cm -3 . At an annealing temperature of 300 o C, the V Ga -related defect began annealing out and a new defect capable of trapping positrons was formed. This newly formed defect, having a lifetime value of 379 ps, is attributed to a vacancy--Zn-defect complex. This defect started annealing out at a temperature of 580 o C. A positron shallow trap having binding energy and concentration of 75 meV and 10 18 cm -3 , respectively, was also observed in the as-grown sample. This shallow trap is attributed to positrons forming hydrogenlike Rydberg states with the ionized dopant acceptor Zn

A study on the thermal expansion characteristics of simulated spent fuel and simulated DUPIC fuel

International Nuclear Information System (INIS)

Kang, Kweon Ho; Ryu, H. J.; Kim, H. S.; Song, K. C.; Yang, M. S.

2001-10-01

Thermal expansions of simulated spent PWR fuel and simulated DUPIC fuel were studied using a dilatometer in the temperature range from 298 to 1900 K. The densities of simulated spent PWR fuel and simulated DUPIC fuel used in the measurement were 10.28 g/cm3 (95.35 % of TD) and 10.26 g/cm3 (95.14 % of TD), respectively. Their linear thermal expansions of simulated fuels are higher than that of UO2, and the difference between these fuels and UO2 increases progressively as temperature increases. However, the difference between simulated spent PWR fuel and simulated DUPIC fuel can hardly be observed. For the temperature range from 298 to 1900 K, the values of the average linear thermal expansion coefficients for simulated spent PWR fuel and simulated DUPIC fuel are 1.391 10-5 and 1.393 10-5 K-1, respectively. As temperature increases to 1900 K, the relative densities of simulated spent PWR fuel and simulated DUPIC fuel decrease to 93.81 and 93.76 % of initial densities at 298 K, respectively

Study on application of positron lifetime spectroscopy in investigation of radiation influences on nuclear track detector polymer

International Nuclear Information System (INIS)

Khuong Thanh Tuan; Tran Dai Nghiep; Nguyen Manh Hung; Nguyen Duc Thanh; Le Anh Tuyen

2007-01-01

Study on determination of micro porosity of materials using positron lifetime technique is an advanced and promoted tendency in physics and material science presently. In Vietnam, studies in this field have been carried out by some projects funded by VAEC in recent few years, with their object is determination of porosity of oil-contained rock and polymers. This project is established to study the relationship between characteristic of positron lifetime spectra and micro porosity of polymer material, which a type of nuclear track detector made from, after irradiation. The experimental result shows a linear relation of a particular characteristic of lifetime spectra - intensity of lifetime components above 1 ns - and the density of track in polymer created by irradiation. (author)

The miscibility and oxidation study of the simulated metallic spent fuel for the development of an advanced spent fuel management process

Energy Technology Data Exchange (ETDEWEB)

Shin, Y. J.; You, G. S.; Ju, J. S.; Lee, E. P.; Seo, H. S.; Ahn, S. B. [Korea Atomic Energy Research Institute, Taejeon (Korea)

1999-03-01

The simulated metallic spent fuel ingots were fabricated and evaluated the oxidation rates and the activation energies under several temperature conditions to develop an advanced spent fuel management process. It was also checked the immiscibility of the some elements with metal uranium. 2 refs., 45 figs. (Author)

Electrochemical performance studies of MnO2 nanoflowers recovered from spent battery

International Nuclear Information System (INIS)

Ali, Gomaa A.M.; Tan, Ling Ling; Jose, Rajan; Yusoff, Mashitah M.; Chong, Kwok Feng

2014-01-01

Highlights: • MnO 2 is recovered from spent zinc–carbon batteries as nanoflowers structure. • Recovered MnO 2 nanoflowers show high specific capacitance. • Recovered MnO 2 nanoflowers show stable electrochemical cycling up to 900 cycles. • Recovered MnO 2 nanoflowers show low resistance in EIS data. - Abstract: The electrochemical performance of MnO 2 nanoflowers recovered from spent household zinc–carbon battery is studied by cyclic voltammetry, galvanostatic charge/discharge cycling and electrochemical impedance spectroscopy. MnO 2 nanoflowers are recovered from spent zinc–carbon battery by combination of solution leaching and electrowinning techniques. In an effort to utilize recovered MnO 2 nanoflowers as energy storage supercapacitor, it is crucial to understand their structure and electrochemical performance. X-ray diffraction analysis confirms the recovery of MnO 2 in birnessite phase, while electron microscopy analysis shows the MnO 2 is recovered as 3D nanostructure with nanoflower morphology. The recovered MnO 2 nanoflowers exhibit high specific capacitance (294 F g −1 at 10 mV s −1 ; 208.5 F g −1 at 0.1 A g −1 ) in 1 M Na 2 SO 4 electrolyte, with stable electrochemical cycling. Electrochemical data analysis reveal the great potential of MnO 2 nanoflowers recovered from spent zinc–carbon battery in the development of high performance energy storage supercapacitor system

Development of spent fuel dry storage technology

International Nuclear Information System (INIS)

Maruoka, Kunio; Matsunaga, Kenichi; Kunishima, Shigeru

2000-01-01

The spent fuels are the recycle fuel resources, and it is very important to store the spent fuels in safety. There are two types of the spent fuel interim storage system. One is wet storage system and another is dry storage system. In this study, the dry storage technology, dual purpose metal cask storage and canister storage, has been developed. For the dual purpose metal cask storage, boronated aluminum basket cell, rational cask body shape and shaping process have been developed, and new type dual purpose metal cask has been designed. For the canister storage, new type concrete cask and high density vault storage technology have been developed. The results of this study will be useful for the spent fuel interim storage. Safety and economical spent fuel interim storage will be realized in the near future. (author)

Spent fuel management

International Nuclear Information System (INIS)

2005-01-01

The production of nuclear electricity results in the generation of spent fuel that requires safe, secure and efficient management. Appropriate management of the resulting spent fuel is a key issue for the steady and sustainable growth of nuclear energy. Currently about 10,000 tonnes heavy metal (HM) of spent fuel are unloaded every year from nuclear power reactors worldwide, of which 8,500 t HM need to be stored (after accounting for reprocessed fuel). This is the largest continuous source of civil radioactive material generated, and needs to be managed appropriately. Member States have referred to storage periods of 100 years and even beyond, and as storage quantities and durations extend, new challenges arise in the institutional as well as in the technical area. The IAEA gives high priority to safe and effective spent fuel management. As an example of continuing efforts, the 2003 International Conference on Storage of Spent Fuel from Power Reactors gathered 125 participants from 35 member states to exchange information on this important subject. With its large number of Member States, the IAEA is well-positioned to gather and share information useful in addressing Member State priorities. IAEA activities on this topic include plans to produce technical documents as resources for a range of priority topics: spent fuel performance assessment and research, burnup credit applications, cask maintenance, cask loading optimization, long term storage requirements including records maintenance, economics, spent fuel treatment, remote technology, and influence of fuel design on spent fuel storage. In addition to broader topics, the IAEA supports coordinated research projects and technical cooperation projects focused on specific needs

Fluorescence lifetime imaging of skin cancer

Science.gov (United States)

Patalay, Rakesh; Talbot, Clifford; Munro, Ian; Breunig, Hans Georg; König, Karsten; Alexandrov, Yuri; Warren, Sean; Neil, Mark A. A.; French, Paul M. W.; Chu, Anthony; Stamp, Gordon W.; Dunsby, Chris

2011-03-01

Fluorescence intensity imaging and fluorescence lifetime imaging microscopy (FLIM) using two photon microscopy (TPM) have been used to study tissue autofluorescence in ex vivo skin cancer samples. A commercially available system (DermaInspect®) was modified to collect fluorescence intensity and lifetimes in two spectral channels using time correlated single photon counting and depth-resolved steady state measurements of the fluorescence emission spectrum. Uniquely, image segmentation has been used to allow fluorescence lifetimes to be calculated for each cell. An analysis of lifetime values obtained from a range of pigmented and non-pigmented lesions will be presented.

Enhanced Thermal Management System for Spent Nuclear Fuel Dry Storage Canister with Hybrid Heat Pipes

International Nuclear Information System (INIS)

Jeong, Yeong Shin; Bang, In Cheol

2016-01-01

Dry storage uses the gas or air as coolant within sealed canister with neutron shielding materials. Dry storage system for spent fuel is regarded as relatively safe and emits little radioactive waste for the storage, but it showed that the storage capacity and overall safety of dry cask needs to be enhanced for the dry storage cask for LWR in Korea. For safety enhancement of dry cask, previous studies of our group firstly suggested the passive cooling system with heat pipes for LWR spent fuel dry storage metal cask. As an extension, enhanced thermal management systems for the spent fuel dry storage cask for LWR was suggested with hybrid heat pipe concept, and their performances were analyzed in thermal-hydraulic viewpoint in this paper. In this paper, hybrid heat pipe concept for dry storage cask is suggested for thermal management to enhance safety margin. Although current design of dry cask satisfies the design criteria, it cannot be assured to have long term storage period and designed lifetime. Introducing hybrid heat pipe concept to dry storage cask designed without disrupting structural integrity, it can enhance the overall safety characteristics with adequate thermal management to reduce overall temperature as well as criticality control. To evaluate thermal performance of hybrid heat pipe according to its design, CFD simulation was conducted and previous and revised design of hybrid heat pipe was compared in terms of temperature inside canister

A Study on Rack Thickness Effect for Spent Fuel Pool Storage

International Nuclear Information System (INIS)

Kim, Mi Jin; Lee, Hee-Jae; Sohn, Dong-Seong

2015-01-01

For the effective storage of used fuel, the development of high performance neutron absorbing materials is needed. One of the major concern for the used fuel storage is the assurance to keep subcriticality of the storage rack and the high performance neutron absorbing material is the vital part to assure this requirement. According to NRC guide line, the k-effective of the spent fuel storage racks must not exceed 0.95. To ensure its safety, subcriticality analysis is required. Subcriticality analysis of the used storage in spent fuel pool have been performed by different authors. Criticality calculations for light water reactor spent fuel storage rack were carried out by Jae et al. They used AMPX-KENO IV code and considered the effect of rack pitch and rack thickness for consolidated fuel. The criticality analysis has performed at Gd 0.2 and 1 wt% according to thickness change. As thickness increases, the volume of the spent fuel pool rack increases. Therefore, absorbing material also increases according to thickness

A Study on Rack Thickness Effect for Spent Fuel Pool Storage

Energy Technology Data Exchange (ETDEWEB)

Kim, Mi Jin; Lee, Hee-Jae; Sohn, Dong-Seong [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

2015-05-15

For the effective storage of used fuel, the development of high performance neutron absorbing materials is needed. One of the major concern for the used fuel storage is the assurance to keep subcriticality of the storage rack and the high performance neutron absorbing material is the vital part to assure this requirement. According to NRC guide line, the k-effective of the spent fuel storage racks must not exceed 0.95. To ensure its safety, subcriticality analysis is required. Subcriticality analysis of the used storage in spent fuel pool have been performed by different authors. Criticality calculations for light water reactor spent fuel storage rack were carried out by Jae et al. They used AMPX-KENO IV code and considered the effect of rack pitch and rack thickness for consolidated fuel. The criticality analysis has performed at Gd 0.2 and 1 wt% according to thickness change. As thickness increases, the volume of the spent fuel pool rack increases. Therefore, absorbing material also increases according to thickness.

Nuclear lifetime measurement

International Nuclear Information System (INIS)

Guillaume, Georges

Three direct techniques of lifetime measurement are emphasized: electronic methods and two methods based on the Doppler effect (the recoil distance methods or RDM, the Doppler shift attenuation methods or DSAM). Said direct methods are concerned with the direct measurement of the radioactive decay constants of nuclear excited states. They allow lifetimes of nucleus bound states whose deexcitations occur by electromagnetic transitions, to be determined. Other methods for measuring lifetimes are also examined: microwave techniques and those involving the blocking effect in crystals (direct methods) and also various indirect methods of obtaining lifetimes (γ resonance scattering, capture reactions, inelastic electron and nucleus scattering, and Coulomb deexcitation) [fr

FUNDUS AUTOFLUORESCENCE LIFETIMES AND CENTRAL SEROUS CHORIORETINOPATHY.

Science.gov (United States)

Dysli, Chantal; Berger, Lieselotte; Wolf, Sebastian; Zinkernagel, Martin S

2017-11-01

To quantify retinal fluorescence lifetimes in patients with central serous chorioretinopathy (CSC) and to identify disease specific lifetime characteristics over the course of disease. Forty-seven participants were included in this study. Patients with central serous chorioretinopathy were imaged with fundus photography, fundus autofluorescence, optical coherence tomography, and fluorescence lifetime imaging ophthalmoscopy (FLIO) and compared with age-matched controls. Retinal autofluorescence was excited using a 473-nm blue laser light and emitted fluorescence light was detected in 2 distinct wavelengths channels (498-560 nm and 560-720 nm). Clinical features, mean retinal autofluorescence lifetimes, autofluorescence intensity, and corresponding optical coherence tomography (OCT) images were further analyzed. Thirty-five central serous chorioretinopathy patients with a mean visual acuity of 78 ETDRS letters (range, 50-90; mean Snellen equivalent: 20/32) and 12 age-matched controls were included. In the acute stage of central serous chorioretinopathy, retinal fluorescence lifetimes were shortened by 15% and 17% in the respective wavelength channels. Multiple linear regression analysis showed that fluorescence lifetimes were significantly influenced by the disease duration (P autofluorescence lifetimes, particularly in eyes with retinal pigment epithelial atrophy, were associated with poor visual acuity. This study establishes that autofluorescence lifetime changes occurring in central serous chorioretinopathy exhibit explicit patterns which can be used to estimate perturbations of the outer retinal layers with a high degree of statistical significance.

Product lifetime, energy efficiency and climate change: A case study of air conditioners in Japan.

Science.gov (United States)

Nishijima, Daisuke

2016-10-01

This study proposed a modelling technique for estimating life-cycle CO2 emissions of durable goods by considering changes in product lifetime and energy efficiency. The stock and flow of durable goods was modelled by Weibull lifetime distributions and the trend in annual energy efficiency (i.e., annual electricity consumption) of an "average" durable good was formulated as a reverse logistic curve including a technologically critical value (i.e., limit energy efficiency) with respect to time. I found that when the average product lifetime is reduced, there is a trade-off between the reduction in emissions during product use (use phase), due to the additional purchases of new, more energy-efficient air conditioners, and the increase in emissions arising from the additional production of new air conditioners stimulated by the reduction of the average product lifetime. A scenario analysis focused on residential air conditioners in Japan during 1972-2013 showed that for a reduction of average lifetime of 1 year, if the air conditioner energy efficiency limit can be improved by 1.4% from the estimated current efficiency level, then CO2 emissions can be reduced by approximately the same amount as for an extension of average product lifetime of 1 year. Copyright © 2016 Elsevier Ltd. All rights reserved.

Burnup credit study and application in spent fuel management in China

International Nuclear Information System (INIS)

Ruan Keqiang; Xue Xiaogang; Shen Leisheng

2001-01-01

This paper gives a brief of spent fuel situation of nuclear power plants in China, problems faced with, and measures to be taken. The main research items in this field in next five years are introduced. It is imperative to put burnup credit to use in spent fuel storage, transport and reprocessing. (author)

Investigation of the condition of spent-fuel pool components

International Nuclear Information System (INIS)

Kustas, F.M.; Bates, S.O.; Opitz, B.E.; Johnson, A.B. Jr.; Perez, J.M. Jr.; Farnsworth, R.K.

1981-09-01

It is currently projected that spent nuclear fuel, which is discharged from the reactor and then stored in water pools, may remain in those pools for several decades. Other studies have addressed the expected integrity of the spent fuel during extended water storage; this study assesses the integrity of metallic spent fuel pool components. Results from metallurgical examinations of specimens taken from stainless steel and aluminum components exposed in spent fuel pools are presented. Licensee Event Reports (LERs) relating to problems with spent fuel components were assessed and are summarized to define the types of operational problems that have occurred. The major conclusions of this study are: aluminum and stainless steel spent fuel pool components have a good history of performance in both deionized and borated water pools. Although some operational problems involving pool components have occurred, these problems have had minimal impacts

Investigation of the condition of spent-fuel pool components

Energy Technology Data Exchange (ETDEWEB)

Kustas, F.M.; Bates, S.O.; Opitz, B.E.; Johnson, A.B. Jr.; Perez, J.M. Jr.; Farnsworth, R.K.

1981-09-01

It is currently projected that spent nuclear fuel, which is discharged from the reactor and then stored in water pools, may remain in those pools for several decades. Other studies have addressed the expected integrity of the spent fuel during extended water storage; this study assesses the integrity of metallic spent fuel pool components. Results from metallurgical examinations of specimens taken from stainless steel and aluminum components exposed in spent fuel pools are presented. Licensee Event Reports (LERs) relating to problems with spent fuel components were assessed and are summarized to define the types of operational problems that have occurred. The major conclusions of this study are: aluminum and stainless steel spent fuel pool components have a good history of performance in both deionized and borated water pools. Although some operational problems involving pool components have occurred, these problems have had minimal impacts.

Application of a cold spray technique to the fabrication of a copper canister for the geological disposal of CANDU spent fuels

Energy Technology Data Exchange (ETDEWEB)

Choi, Heui-Joo, E-mail: hjchoi@kaeri.re.k [Korea Atomic Energy Research Institute, Radioactive Waste Management Technology Development, 150 Dukjin-dong, Yuseong, Daejon, 305-353 (Korea, Republic of); Lee, Minsoo; Lee, Jong Youl [Korea Atomic Energy Research Institute, Radioactive Waste Management Technology Development, 150 Dukjin-dong, Yuseong, Daejon, 305-353 (Korea, Republic of)

2010-10-15

A new method was proposed for the manufacture of a copper-cast iron canister for the spent fuel disposal based on the cold spray coating technique. The thickness of a copper shell could be fabricated to be as thin as 10 mm with the new method. Around 6 tons of copper could be saved with a 10 mm thick canister compared with a 50 mm thick canister. The electrochemical properties of the cold sprayed copper layer and forged copper were measured through a polarization test. The two copper layers showed very similar electrochemical properties. The lifetime of a 10 mm copper canister was estimated with a mathematical model based on the mass transport of sulfide ions through the buffer. The results showed that the canister lifetime was more than 140,000 years under the Korean granite groundwater condition. The thermal analysis with a current pre-conceptual design of a CANDU spent fuel canister showed that the maximum temperature between the canister and the saturated buffer was below the thermal criteria, 100 {sup o}C. Finally, the mechanical stability of the copper canister was confirmed with a computer program, ABAQUS, under the rock movement scenario.

Study of multiplication factor sensitivity to the spread of WWER spent fuel isotopics calculated by different codes

International Nuclear Information System (INIS)

Markova, L.

2001-01-01

As a sensitivity study the impact on the system reactivity was studied in the case that different calculational methodologies of spent fuel isotopic concentrations were used for WWER spent fuel inventory computations. The sets of isotopic concentrations obtained by calculations with different codes and libraries as a result of the CB2 international benchmark focused on WWER-440 burnup credit were used to show the spread of the calculated spent fuel system reactivity. Using the MCNP 4B code and changing the isotopics input data, the multiplication factor of an infinite array of the WWER-440 fuel pin cells was calculated. The evaluation of the results shows the sensitivity of the calculated reactivity to different calculational methodologies used for the spent fuel inventory computation. In the studied cases of the CB2 benchmark, the spread of the reference k-results relative to the mean was found less or about ±1% in spite of the fact that the data of isotopic concentrations were spread much more. (author)

Multiple Myeloma and lifetime occupation: results from the EPILYMPH study

Directory of Open Access Journals (Sweden)

Perrotta Carla

2012-12-01

Full Text Available Abstract Background The EPILYMPH study applied a detailed occupational exposure assessment approach to a large multi-centre case–control study conducted in six European countries. This paper analysed multiple myeloma (MM risk associated with level of education, and lifetime occupational history and occupational exposures, based on the EPILYMPH data set. Methods 277 MM cases and four matched controls per each case were included. Controls were randomly selected, matching for age (+/− 5 years, centre and gender. Lifetime occupations and lifetime exposure to specific workplace agents was obtained through a detailed questionnaire. Local industrial hygienists assessed likelihood and intensity for specific exposures. The odds ratio and 95% confidence intervals (OR, 95% CI were calculated for level of education, individual occupations and specific exposures. Unconditional logistic regression models were run for individual occupations and exposures. Results A low level of education was associated with MM OR=1.68 (95% CI 1.02-2.76. An increased risk was observed for general farmers (OR=1.77; 95% CI 1.05-2.99 and cleaning workers (OR=1.69; 95% CI 1.04-2.72 adjusting for level of education. Risk was also elevated, although not significant, for printers (OR=2.06; 95% CI 0.97-4.34. Pesticide exposure over a period of ten years or more increased MM risk (OR=1.62; 95% CI 1.01-2.58. Conclusion These results confirm an association of MM with farm work, and indicate its association with printing and cleaning. While prolonged exposure to pesticides seems to be a risk factor for MM, an excess risk associated with exposure to organic solvents could not be confirmed.

Pacific Northwest Laboratory (PNL) spent fuel transportation and handling facility models

Energy Technology Data Exchange (ETDEWEB)

Andrews, W.B.; Bower, J.C.; Burnett, R.A.; Engel, R.L.; Rolland, C.W.

1979-09-01

A spent fuel logistics study was conducted in support of the US DOE program to develop facilities for preparing spent unreprocessed fuel from commercial LWRs for geological storage. Two computerized logistics models were developed. The first one was the site evaluation model. Two studies of spent fuel handling facility and spent fuel disposal facility siting were completed; the first postulates a single spent fuel handling facility located at any of six DOE laboratory sites, while the second study examined siting strategies with the spent fuel repository relative to the spent fuel handling facility. A second model to conduct storage/handling facility simulations was developed. (DLC)

Pacific Northwest Laboratory (PNL) spent fuel transportation and handling facility models

International Nuclear Information System (INIS)

Andrews, W.B.; Bower, J.C.; Burnett, R.A.; Engel, R.L.; Rolland, C.W.

1979-09-01

A spent fuel logistics study was conducted in support of the US DOE program to develop facilities for preparing spent unreprocessed fuel from commercial LWRs for geological storage. Two computerized logistics models were developed. The first one was the site evaluation model. Two studies of spent fuel handling facility and spent fuel disposal facility siting were completed; the first postulates a single spent fuel handling facility located at any of six DOE laboratory sites, while the second study examined siting strategies with the spent fuel repository relative to the spent fuel handling facility. A second model to conduct storage/handling facility simulations was developed

Intermodal transfer of spent fuel

International Nuclear Information System (INIS)

Neuhauser, K.S.; Weiner, R.F.

1991-01-01

As a result of the international standardization of containerized cargo handling in ports around the world, maritime shipment handling is particularly uniform. Thus, handier exposure parameters will be relatively constant for ship-truck and ship-rail transfers at ports throughout the world. Inspectors' doses are expected to vary because of jurisdictional considerations. The results of this study should be applicable to truck-to-rail transfers. A study of the movement of spent fuel casks through ports, including the loading and unloading of containers from cargo vessels, afforded an opportunity to estimate the radiation doses to those individuals handling the spent fuels with doses to the public along subsequent transportation routes of the fuel. A number of states require redundant inspections and for escorts over long distances on highways; thus handlers, inspectors, escort personnel, and others who are not normally classified as radiation workers may sustain doses high enough to warrant concern about occupational safety. This paper addresses the question of radiation safety for these workers. Data were obtained during, observation of the offloading of reactor spent fuel (research reactor spent fuel, in this instance) which included estimates of exposure times and distances for handlers, inspectors and other workers during offloading and overnight storage. Exposure times and distance were also for other workers, including crane operators, scale operators, security personnel and truck drivers. RADTRAN calculational models and parameter values then facilitated estimation of the dose to workers during incident-free ship-to-truck transfer of spent fuel

Guidebook on spent fuel storage

International Nuclear Information System (INIS)

1984-01-01

The Guidebook summarizes the experience and information in various areas related to spent fuel storage: technological aspects, the transport of spent fuel, economical, regulatory and institutional aspects, international safeguards, evaluation criteria for the selection of a specific spent fuel storage concept, international cooperation on spent fuel storage. The last part of the Guidebook presents specific problems on the spent fuel storage in the United Kingdom, Sweden, USSR, USA, Federal Republic of Germany and Switzerland

Hadronization, spin and lifetimes

International Nuclear Information System (INIS)

Grossman, Yuval; Nachshon, Itay

2008-01-01

Measurements of lifetimes can be done in two ways. For very short lived particles, the width can be measured. For long lived ones, the lifetime can be directly measured, for example, using a displaced vertex. Practically, the lifetime cannot be extracted for particles with intermediate lifetimes. We show that for such cases information about the lifetime can be extracted for heavy colored particles that can be produced with known polarization. For example, a t-like particle with intermediate lifetime hadronizes into a superposition of the lowest two hadronic states, T* and T (the equivalent of B* and B). Depolarization effects are governed by time scales that are much longer than the hadronization time scale, Λ QCD -1 . After a time of order 1/Δm, with Δm≡m(T*)-m(T), half of the initial polarization is lost. The polarization is totally lost after a time of order 1/Γ γ , with Γ γ = Γ(T* → Tγ). Thus, by comparing the initial and final polarization, we get information on the particle's lifetime.

The Lifetime of a beautiful and charming meson: Bc lifetime measured using the D0 detector

International Nuclear Information System (INIS)

Welty-Rieger, Leah Christine

2008-01-01

Using approximately 1.3 fb -1 of data collected by the D0 detector between 2002 and 2006, the lifetime of the B c ± meson is studied in the B c ± → J/ψμ ± + X final state. Using an unbinned likelihood simultaneous fit to J/ψ + μ invariant mass and lifetime distributions, a signal of 810 ± 80(stat.) candidates is estimated and a lifetime measurement made of: τ(B c ± ) = 0.448 -0.036 +0.038 (stat) ± 0.032(sys) ps

Thermal stability of grain boundaries in nanocrystalline Zn studied by positron lifetime spectroscopy

International Nuclear Information System (INIS)

Zhou Kai; Li Hui; Pang Jinbiao; Wang Zhu

2012-01-01

Nanocrystalline Zn prepared by compacting nanoparticles with mean grain size about 55 nm at 15 MPa has been studied by positron lifetime spectroscopy. For the bulk Zn sample, the vacancy defect is annealed out at about 350 °C, but for the nanocrystalline Zn sample, the vacancy cluster in grain boundaries is quite difficult to be annealed out even at very high temperature (410 °C). In the grain boundaries of nanocrystalline Zn, the small free volume defect (not larger than divacancy) is dominant according to the high relative intensity for the short positron lifetime (τ 1 ). The oxide (ZnO) inside the grain boundaries has been found having an effect to hinder the decrease of average positron lifetime (τ av ), which probably indicates that the oxide stabilizes the microstructure of the grain boundaries. This stabilization is very important for the nanocrystalline materials using as radiation resistant materials.

Nondestructive verification and assay systems for spent fuels

International Nuclear Information System (INIS)

Cobb, D.D.; Phillips, J.R.; Bosler, G.E.; Eccleston, G.W.; Halbig, J.K.; Hatcher, C.R.; Hsue, S.T.

1982-04-01

This is an interim report of a study concerning the potential application of nondestructive measurements on irradiated light-water-reactor (LWR) fuels at spent-fuel storage facilities. It describes nondestructive measurement techniques and instruments that can provide useful data for more effective in-plant nuclear materials management, better safeguards and criticality safety, and more efficient storage of spent LWR fuel. In particular, several nondestructive measurement devices are already available so that utilities can implement new fuel-management and storage technologies for better use of existing spent-fuel storage capacity. The design of an engineered prototype in-plant spent-fuel measurement system is approx. 80% complete. This system would support improved spent-fuel storage and also efficient fissile recovery if spent-fuel reprocessing becomes a reality

Logistics characterization for regional spent fuel repositories concept

International Nuclear Information System (INIS)

Joy, D.S.; Hudson, B.J.; Anthony, M.W.

1980-08-01

This report summarizes a study of logistics considerations for a four-region repository system for spent fuel disposal. The logistics considerations include: (1) yearly receipt and emplacement; (2) inventory; (3) away-from-reactor (AFR) storage; (4) nuclear capacity growth effects; (5) entire lifetime of reactors served by repository operations; (6) proportions of pressurized-water-reactor (PWR)/boiling-water-reactor (BWR) fuel; (7) proportions of rail and truck shipments; (8) shipping cask fleet requirements; (9) number of annual shipments; (10) mode (rail/truck) and cost of shipment; and (11) initial year for shipment to maintain full core reserve. The nation was divided into Northeast, North Central, Southern, and Western regions for evaluation purposes. Repository logistics were analyzed in each region based on three different capacity projections. For the Southern region, results for seven salt dome sites are presented. The Western region results cover four potential sites. The North Central and Northeastern regions results are not presented on a site specific basis. Conclusions are drawn based on the results. The methodology assumptions and references used in the logistics analysis are described for the convenience of the reader

Lifetime Studies of Cs2Te Cathodes at the Phin RF Photoinjector at CERN

CERN Document Server

Hessler, C; Divall Csatari, M; Doebert, S; Fedosseev, V

2012-01-01

The PHIN photoinjector has been developed to study the feasibility of a photoinjector option for the CLIC (Compact LInear Collider) drive beam as an alternative to the baseline design, using a thermionic gun. The CLIC drive beam requires a high charge of 8.4 nC per bunch in 0.14 ms long trains, with 2 ns bunch spacing and 50 Hz macro pulse repetition rate, which corresponds to a total charge per macro pulse of 0.59 mC. This means unusually high peak and average currents for photoinjectors and is challenging concerning the cathode lifetime. In this paper detailed studies of the lifetime of Cs2Te cathodes, produced by the co-evaporation technique, are presented with respect to bunch charge, train length and vacuum level. Furthermore, the impact of the train length and bunch charge on the vacuum level will be discussed and steps to extend the lifetime will be outlined.

Studies on certain quality attributes of meat pickle prepared from spent chicken

Directory of Open Access Journals (Sweden)

Dilip Ranjan Nath

2013-06-01

Full Text Available Aim: An attempt was made to develop a desirable meat pickle from the less tender and low demand spent chicken meat with the prime objective of its better marketability and wider acceptability amongst the non-vegetarian masses. Materials and Methods: Lean of culled spent meat was marinated for overnight and then pressure cooked and fried with spices and condiments to prepare a shelf stable meat pickle. Proximate composition, pH, TBA Values, Total viable plate count, Counts for yeast and moulds and sensory quality of the pickles were studied as per standard procedure. Results: The mean per cent moisture, crude protein, ether extract and total ash contents were 61.89±0.12, 17.28±0.56, 14.65±0.16 and 3.35±0.17 respectively. The product pH and the yeast and mould counts though did not differ significantly amongst the storage periods, yet there were significant differences (p<0.01 in TBA and total viable plate count amongst the storage periods. Organoleptic studies with score card method recorded a progressive decrease in the mean panel scores along with the increased storage periods. Conclusion: The spent chicken meat pickle was found to be acceptable for consumption up-to 90 days of storage at room temperature. [Vet World 2013; 6(3.000: 156-158

Lifetime of Bentonites study: hydrothermal stability of saponites; Estudio de longevidad en bentonitas: estabilidad hidrotermal de saponitas

Energy Technology Data Exchange (ETDEWEB)

Leguey, S; Cuevas, J; Garralon, A [Universidad Autonoma de Madrid, Facultad de Ciencias, Departamento de Quimica Agricola, Geologia y Geoquimica, Madrid (Spain)

1996-10-01

The report studies the lifetime of bentonite and the hydrothermal stability of saponites. The testing comprised determination of physical and chemical properties of clays, the stability of the mineral porosity, lifetime and the wall of clay.

Final environmental statement: US Spent Fuel Policy. Storage of foreign spent power reactor fuel

International Nuclear Information System (INIS)

1980-05-01

In October 1977, the Department of Energy (DOE) announced a Spent Fuel Storage Policy for nuclear power reactors. Under this policy, as approved by the President, US utilities will be given the opportunity to deliver spent fuel to US Government custody in exchange for payment of a fee. The US Government will also be prepared to accept a limited amount of spent fuel from foreign sources when such action would contribute to meeting nonproliferation goals. Under the new policy, spent fuel transferred to the US Government will be delivered - at user expense - to a US Government-approved site. Foreign spent fuel would be stored in Interim Spent Fuel Storage (ISFS) facilities with domestic fuel. This volume of the environmental impact statement includes effects associated with implementing or not implementing the Spent Fuel Storage Policy for the foreign fuels. The analyses show that there are no substantial radiological health impacts whether the policy is implemented or not. In no case considered does the population dose commitment exceed 0.000006% of the world population dose commitment from natural radiation sources over the period analyzed. Full implementation of the US offer to accept a limited amount of foreign spent fuel for storage provides the greatest benefits for US nonproliferation policy. Acceptance of lesser quantities of foreign spent fuel in the US or less US support of foreign spent fuel storage abroad provides some nonproliferation benefits, but at a significantly lower level than full implementation of the offer. Not implementing the policy in regard to foreign spent fuel will be least productive in the context of US nonproliferation objectives. The remainder of the summary provides a brief description of the options that are evaluated, the facilities involved in these options, and the environmental impacts, including nonproliferation considerations, associated with each option

SOCIAL INTEGRATION: TESTING ANTECEDENTS OF TIME SPENT ONLINE

Directory of Open Access Journals (Sweden)

Lily Suriani Mohd Arif

2013-07-01

Full Text Available The literature on the relationship of social integration and time spent onlineprovides conflicting evidence of the relationship of social integration with timespent online. The study identifies and highlightsthe controversy and attempts toclarify the relationship of social integration withtime spent online bydecomposing the construct social integration into its affective and behavioraldimensions . Thestudy tests antecedents and effects of time spent online in arandom sample of senior level undergraduate students at a public university inMalaysia. The findings indicated that while self-report measures of behavioralsocial integration did not predict time spent online, and, the affective socialintegration had an inverse relationship with time spent online.

Assessment of LMFBR spent fuel shipping cask concepts for the CRBRP and the US conceptual design study

International Nuclear Information System (INIS)

Pope, R.B.; Ortman, J.M.; Eakes, R.G.; Leisher, W.B.; Dupree, S.A.

1980-01-01

Study of conceptual shipping systems for CRBRP and CDS spent fuel has shown that systems significantly different from those used for LWR spent fuel will be required. In the conceptual design, liquid sodium was assumed to be the coolant in canisters containing the spent fuel assemblies, and multiple levels of containment were provided by canisters, an inner cask lid and an outer cask lid. Cask cooling at the reactor site during loading, and cooldown at the receiving site prior to unloading are significant but tractable problems

Positron lifetime studies in undoped and Sr doped La2CuO4

International Nuclear Information System (INIS)

Sundar, C.S.; Bharathi, A.; Hariharan, Y.; Vasumathi, D.

1992-01-01

The results of positron lifetime measurements as a function of temperature, in undoped and Sr doped La 2 CuO 4 are presented. A second component of lifetime with a value of 225 ps is seen to develop after 100degC, whose intensity grows sharply in the range of 100degC to 250degC. The mean lifetime increases from 170 ps to 207 ps as the temperature is increased from room temperature to 300degC. Using the results of the theoretical calculations of positron lifetimes at vacancies in La 2 CuO 4 , it is argued that the increase in lifetime with temperature is due to positron trapping at the thermally generated La vacancies. From a two state trapping model analysis, the formation energy is estimated to be 0.39±0.04 eV

Studies of unicellular microorganisms Saccharomyces cerevisiae by means of positron annihilation lifetime spectroscopy

Directory of Open Access Journals (Sweden)

Kubicz Ewelina

2015-12-01

Full Text Available Results of positron annihilation lifetime spectroscopy (PALS and microscopic studies on simple microorganisms, brewing yeasts, are presented. Lifetime of ortho-positronium (o-Ps were found to change from 2.4 to 2.9 ns (longer-lived component for lyophilized and aqueous yeasts, respectively. Also hygroscopicity of yeasts in time was examined, allowing to check how water – the main component of the cell – affects PALS parameters, thus lifetime of o-Ps were found to change from 1.2 to 1.4 ns (shorter-lived component for the dried yeasts. The time sufficient to hydrate the cells was found below 10 hours. In the presence of liquid water, an indication of reorganization of yeast in the molecular scale was observed. Microscopic images of the lyophilized, dried, and wet yeasts with best possible resolution were obtained using inverted microscopy (IM and environmental scanning electron microscopy (ESEM methods. As a result, visible changes to the surface of the cell me mbrane were observed in ESEM images.

Fluorescence lifetime studies of MeV erbium implanted silica glass

International Nuclear Information System (INIS)

Lidgard, A.; Polman, A.; Jacobsen, D.C.; Blonder, G.E.; Kistler, R.; Poate, J.M.; Becker, P.C.

1991-01-01

MeV erbium ion implantation into various SiO 2 glasses has been studied with the aim of incorporating the rare-earth dopant as an optically active ion in the silica network. The lifetime of the excited state ranges from 1.6 to 12.8 ms, depending on base material and implantation fluence. These results have positive implications for silica-based integrated optical technology. (Author)

Fluorescence lifetime studies of MeV erbium implanted silica glass

Energy Technology Data Exchange (ETDEWEB)

Lidgard, A.; Polman, A.; Jacobsen, D.C.; Blonder, G.E.; Kistler, R.; Poate, J.M.; Becker, P.C. (AT and T Bell Labs., Murray Hill, NJ (USA))

1991-05-23

MeV erbium ion implantation into various SiO{sub 2} glasses has been studied with the aim of incorporating the rare-earth dopant as an optically active ion in the silica network. The lifetime of the excited state ranges from 1.6 to 12.8 ms, depending on base material and implantation fluence. These results have positive implications for silica-based integrated optical technology. (Author).

The study on radioactivity reduction of spent PWR cladding hull

International Nuclear Information System (INIS)

Jung, I. H.; Kim, J. H.; Park, C. J.; Jung, Y. H.; Song, K. C.; Lee, J. W.; Park, J. J.; Yang, M. S.

2003-01-01

Hull arising from the spent PWR fuel elements is classified as a high-level radioactive waste. This report describes the radio-chemical characteristics of the hull-from PWR spent fuel of 32,000MWd/tU burn-up and 15 years cooling, discharged from Gori Unit I cycled 4-7-by examination and literature survey. On the basis of the results, a method of degradation to middle and low-level radioactive waste was proposed by dry process such as laser or plasma technique with removing the nuclides deposited on the surface of the hull

Spent Pot Lining Characterization Framework

Science.gov (United States)

Ospina, Gustavo; Hassan, Mohamed I.

2017-09-01

Spent pot lining (SPL) management represents a major concern for aluminum smelters. There are two key elements for spent pot lining management: recycling and safe storage. Spent pot lining waste can potentially have beneficial uses in co-firing in cement plants. Also, safe storage of SPL is of utmost importance. Gas generation of SPL reaction with water and ignition sensitivity must be studied. However, determining the feasibility of SPL co-firing and developing the required procedures for safe storage rely on determining experimentally all the necessary SPL properties along with the appropriate test methods, recognized by emissions standards and fire safety design codes. The applicable regulations and relevant SPL properties for this purpose are presented along with the corresponding test methods.

Positron lifetime in vacancy clusters. Application to the study of vacancy-impurity interactions

International Nuclear Information System (INIS)

Corbel, C.

1986-02-01

Positron lifetime measurements are used to study the vacancy recovery (77-650 K) in 20 K electron irradiated dilute gold or iron alloys in stainless steels. Positron lifetimes in clusters of various shapes and structures are calculated to precise the information obtained by measuring the positron lifetime in a vacancy cluster of unknown size and configuration. From the calculations, we have drawn the following conclusions: - the minimal size of an unknown cluster can be deduced from the measurement of the positron lifetime in the cluster; - a decrease of the positron lifetime when the structure of the cluster evolves, means either a decrease of the size of the cluster, or, the appearance of a relaxed configuration. - The positron lifetime is very useful to discriminate between a spatial planar or relaxed configuration and a tri-dimensional one. In AuGe, AuSb, AuTn alloys, vacancy clusters decorated by solute atoms appear at 250 K. Their configurations are different from those in pure Au. Mobile vacancy-solutes complexes are involved in the clustering process in AuGe, AuSb. The clusters are probably decorated by several solute atoms in AuGe and AuSb where the resistivity evidences a clustering of solute atoms. In AuFe, vacancy-single or multi-complexes stable up to 670 K prevent cluster formation. In FeTi, FeSb, FeAu, vacancy migration is hindered by the formation of vacancy-solute complexes up to 315 K (Ti), up to 670 K (Sb), up to 700 K (Au). In FeSi, FeCu, FeAg, tri-dimensional clusters grow less easily than Fe. This is likely due to the formation of several kinds of small decorated clusters with relaxed or planar configurations. They are peculiarly stable, surviving up to 700 K at least. In Si (resp. Ti) doped 59Fe25Ni16Cr, solute atoms retain the vacancies up to 300 K (resp. 320 K) [fr

Spent fuel storage facility, Kalpakkam

International Nuclear Information System (INIS)

Shreekumar, B.; Anthony, S.

2017-01-01

Spent Fuel Storage Facility (SFSF), Kalpakkam is designed to store spent fuel arising from PHWRs. Spent fuel is transported in AERB qualified/authorized shipping cask by NPCIL to SFSF by road or rail route. The spent fuel storage facility at Kalpakkam was hot commissioned in December 2006. All systems, structures and components (SSCs) related to safety are designed to meet the operational requirements

Spent fuel storage and isolation

International Nuclear Information System (INIS)

Bensky, M.S.; Kurzeka, W.J.; Bauer, A.A.; Carr, J.A.; Matthews, S.C.

1979-02-01

The principal spent fuel activities conducted within the commercial waste and spent fuel within the Commercial Waste and Spent Fuel Packaging Program are: simulated near-surface (drywell) storage demonstrations at Hanford and the Nevada Test Site; surface (sealed storage cask) and drywell demonstrations at the Nevada Test Site; and spent fuel receiving and packaging facility conceptual design. These investigations are described

A study on radiation shielding design in MACSTOR-400(CANDU spent fuel storage facility)

International Nuclear Information System (INIS)

Lee, Yoon Hee

2006-02-01

Since the spent fuel pool will be saturated in the near future, spent fuel storage facilities are urgently needed. Because of high radiation and decay heat, spent fuel management is difficult and important. In this study, the shielding thickness of MACSTOR-400 that satisfies the general surface dose rate limit has been investigated. And the radiation shielding safety at site boundary has also been evaluated. IAEA recommends the safety series as a guideline and the U.S. follows the NUREG guide for spent fuel storage facility design. In Japan, the regulation for internal transfer is applied to the spent fuel storage. In Korea, the ACT notification for radiation protection is considered. As a shielding design requirement, it is stated that the occupational exposure dose rate must not exceed 1 mSv/week. From this value, it is assumed that the surface dose rate limit is 25 μSv/hr. And for multi unit operation in same site, the dose rate limit at the controlled area boundary is 0.25 mSv/yr. MCNP code and Microshield program were used for calculating the surface dose rate and the dose rate at site boundary respectively. The shielding should be at least 90 cm thick except the air inlet to follow the surface dose rate limit. Additional shielding is needed on air inlet because the dose rate on air inlet is higher than the dose rate on concrete surface. Without the shielding structure, the shielding thickness should be at least 127 cm. In order to satisfy the surface dose rate limit with maintaining the same concrete thickness on air inlet, shielding structure is required on air inlet. The optimum shielding structure has been proposed in this study. The allowable number of MACSTORs with considering other nuclear facilities in Wolsung site is calculated at 60. It is expected that the required number of MACSTORs are 28 in order to store the total amount of spent fuel generated during NPP operation in Wolsung. Therefore, it seems to be safe in radiation point at site boundary

A study on radiation shielding design in MACSTOR-400(CANDU spent fuel storage facility)

Energy Technology Data Exchange (ETDEWEB)

Lee, Yoon Hee

2006-02-15

Since the spent fuel pool will be saturated in the near future, spent fuel storage facilities are urgently needed. Because of high radiation and decay heat, spent fuel management is difficult and important. In this study, the shielding thickness of MACSTOR-400 that satisfies the general surface dose rate limit has been investigated. And the radiation shielding safety at site boundary has also been evaluated. IAEA recommends the safety series as a guideline and the U.S. follows the NUREG guide for spent fuel storage facility design. In Japan, the regulation for internal transfer is applied to the spent fuel storage. In Korea, the ACT notification for radiation protection is considered. As a shielding design requirement, it is stated that the occupational exposure dose rate must not exceed 1 mSv/week. From this value, it is assumed that the surface dose rate limit is 25 μSv/hr. And for multi unit operation in same site, the dose rate limit at the controlled area boundary is 0.25 mSv/yr. MCNP code and Microshield program were used for calculating the surface dose rate and the dose rate at site boundary respectively. The shielding should be at least 90 cm thick except the air inlet to follow the surface dose rate limit. Additional shielding is needed on air inlet because the dose rate on air inlet is higher than the dose rate on concrete surface. Without the shielding structure, the shielding thickness should be at least 127 cm. In order to satisfy the surface dose rate limit with maintaining the same concrete thickness on air inlet, shielding structure is required on air inlet. The optimum shielding structure has been proposed in this study. The allowable number of MACSTORs with considering other nuclear facilities in Wolsung site is calculated at 60. It is expected that the required number of MACSTORs are 28 in order to store the total amount of spent fuel generated during NPP operation in Wolsung. Therefore, it seems to be safe in radiation point at site boundary

Lifetime measurements

International Nuclear Information System (INIS)

Poletti, A.R.

1976-01-01

Recent developments in experimental methods of measuring the lifetimes of excited nuclear states is reviewed in three main areas. (a) Doppler Shift Attenuation Measurements (DSAM) Times: 10 -14 - 10 -11 sec.; (b) Recoil Distance Measurements (RDM) Times: 10 -9 - 10 -12 sec.; (c) Direct Electronic Timing Times: down to 10 -10 sec.; A measurement of an excited state lifetime can answer a large number of different questions. Two examples are discussed: (a) The determination of the lifetime of an isomeric transition in 93 Tc and its use in determining an upper limit for the magnitude of the parity non-conserving matrix element - /Hsub(PN)/17/2 + >. (b) The dependence of the strength of M2 transitions on isospin in nuclei in the 1dsub(3/2) -1fsub(7/2) region. (author)

Spent fuel transportation in the United States: commercial spent fuel shipments through December 1984

International Nuclear Information System (INIS)

1986-04-01

This report has been prepared to provide updated transportation information on light water reactor (LWR) spent fuel in the United States. Historical data are presented on the quantities of spent fuel shipped from individual reactors on an annual basis and their shipping destinations. Specifically, a tabulation is provided for each present-fuel shipment that lists utility and plant of origin, destination and number of spent-fuel assemblies shipped. For all annual shipping campaigns between 1980 and 1984, the actual numbers of spent-fuel shipments are defined. The shipments are tabulated by year, and the mode of shipment and the casks utilized in shipment are included. The data consist of the current spent-fuel inventories at each of the operating reactors as of December 31, 1984. This report presents historical data on all commercial spent-fuel transportation shipments have occurred in the United States through December 31, 1984

Spent fuel dissolution mechanisms

International Nuclear Information System (INIS)

Ollila, K.

1993-11-01

This study is a literature survey on the dissolution mechanisms of spent fuel under disposal conditions. First, the effects of radiolysis products on the oxidative dissolution mechanisms and rates of UO 2 are discussed. These effects have mainly been investigated by using electrochemical methods. Then the release mechanisms of soluble radionuclides and the dissolution of the UO 2 matrix including the actinides, are treated. Experimental methods have been developed for measuring the grain-boundary inventories of radionuclides. The behaviour of cesium, strontium and technetium in leaching tests shows different trends. Comparison of spent fuel leaching data strongly suggests that the release of 90 Sr into the leachant can be used as a measure of the oxidation/dissolution of the fuel matrix. Approaches to the modelling UO 2 , dissolution are briefly discussed in the next chapter. Lastly, the use of natural material, uraninite, in the evaluation of the long-term performance of spent fuel is discussed. (orig.). (81 ref., 37 figs., 8 tabs.)

Corrosion of spent Advanced Test Reactor fuel

International Nuclear Information System (INIS)

Lundberg, L.B.; Croson, M.L.

1994-01-01

The results of a study of the condition of spent nuclear fuel elements from the Advanced Test Reactor (ATR) currently being stored underwater at the Idaho National Engineering Laboratory (INEL) are presented. This study was motivated by a need to estimate the corrosion behavior of dried, spent ATR fuel elements during dry storage for periods up to 50 years. The study indicated that the condition of spent ATR fuel elements currently stored underwater at the INEL is not very well known. Based on the limited data and observed corrosion behavior in the reactor and in underwater storage, it was concluded that many of the fuel elements currently stored under water in the facility called ICPP-603 FSF are in a degraded condition, and it is probable that many have breached cladding. The anticipated dehydration behavior of corroded spent ATR fuel elements was also studied, and a list of issues to be addressed by fuel element characterization before and after forced drying of the fuel elements and during dry storage is presented

Dynamic aperture study and lifetime improvement at the Advanced Photon Source

International Nuclear Information System (INIS)

Sajaev, V.; Emery, L.

2006-01-01

Over the past few years, the optics of the Advanced Photon Source storage ring has been optimized to provide lower natural emittance. Presently, the APS operates at 2.5 nm-rad emittance. The optimization was done at the expense of stronger sextupoles and shorter lifetime. Here we present our work on measurement and understanding of the dynamic aperture of the APS in low-emittance mode. We found good agreement between the dynamic aperture measurements and that of the model derived from the response matrix analysis. Based on the model, we were able to increase the lifetime significantly by optimizing sextupoles, correcting optics, moving a working point, and adjusting rf voltage. The higher lifetime allowed us to decrease operating coupling from 2.5% to 1%.

Modeling the highway transportation of spent fuel

International Nuclear Information System (INIS)

Harrison, I.G.

1986-01-01

There will be a substantial increase in the number of spent fuel shipments on the nation's highway system in the next thirty years. Most of the spent fuel will be moving from reactors to a spent fuel repository. This study develops two models that evaluate the risk and cost of moving the spent fuel. The Minimum Total Transport Risk Model (MTTRM) seeks an efficient solution for this problem by finding the minimum risk path through the network and sending all the spent fuel shipments over this one path. The Equilibrium Transport Risk Model (ETRM) finds an equitable solution by distributing the shipments over a number of paths in the network. This model decreases the risk along individual paths, but increases society's risk because the spent fuel shipments are traveling over more links in the network. The study finds that there is a trade off between path risk and societal risk. As path risk declines, societal risk rises. The cost of shipping also increases as the number of paths expand. The cost and risk of shipping spent fuel from ten reactors to four potential repository sites are evaluated using the MTTRM. The temporary monitored retrievable storage (MRS) facility in Tennessee is found to be the minimum cost and minimum risk solution. When direct shipment to the permanent sites is considered, Deaf Smith, Texas is the least cost and least incident free transport risk location. Yucca Mountain, Nevada is the least risk location when the focus is placed on the potential consequences of an accident

Use of three-dimensional lognormal dose-response surfaces in lifetime studies of radiation-induced cancer

International Nuclear Information System (INIS)

Raabe, O.G.

1986-01-01

The three-dimensional lognormal cumulative probability power function was used to provide a unifying dose-response description of the lifetime cancer risk for chronic exposure of experimental animals and people, for risk evaluation, and for scaling between species. Bone tumor fatilities, primarily from alpha irradiation of the skeleton in lifetime studies of beagles injected with 226 Ra, were shown to be well described by this function. This function described cancer risk in lifetime studies as a curved smooth surface depending on radiation exposure rate and elapsed time, such that the principal risk at low dose rates occurred near the end of the normal life span without significant life shortening. Essentially identical functions with the median value of the power function displaced with respect to appropriate RBE values were shown to describe bone-cancer induction primarily from alpha irradiation of the skeleton in lifetime beagle studies with injected 226 Ra, 228 Th, 239 Pu and 241 Am, and with inhaled 238 Pu. Application of this model to human exposures to 226 Ra yielded a response ratio of 3.6; that is, the time required for development of bone cancer in people was 3.6 times longer than for beagles at the same average skeletal dose rate. It was suggested that similar techniques were appropriate to other carcinogens and other critical organs. 20 refs., 8 figs., 3 tabs

Searching for Methods on Evaluation Alternatives and Studying Decision Making System Regarding Enhancing Publicity of Nuclear Spent Fuel

International Nuclear Information System (INIS)

Cho, Seongkyung; Choi, Seungho; Kim, Hyerim; Song, Jiyeon; Lee, Yoonsup; Sohn, Seohyun

2013-01-01

This study was done in order to anticipate the aspect of publicity enhancement on nuclear spent fuel so that it can find the evaluation methods of alternative ways of management which could applied actually and make the decision making system of Publicity Enhancement Committee in advance. In Korea, the nuclear spent fuel is temporarily stored inside of the nuclear facility field, and it is expected that Gori nuclear facility is going to be saturated since 2016 but the solutions are still incomplete. The problem of management of nuclear spent fuel is an important issue in terms of not only the nuclear power policy but also of safe management of the already made nuclear spent fuel. This study has its meaning to draw the evaluation criteria of the management alternatives on nuclear spent fuel which can be applied in Korean case, and to find the necessity of verifying the evaluation of management alternatives through Publicity Enhancement because of different stands according to the interests. As a result, rather than technological engineering safety evaluation, qualitative analysis in terms of social costs, quantitative evaluation in terms of economic costs, this study advises the methods of public hearings and citizen juries which are effective, which makes it meaningful

The Spent Fuel Management in Finland and Modifications of Spent Fuel Storages

International Nuclear Information System (INIS)

Maaranen, Paeivi

2014-01-01

The objective of this presentation is to share the Finnish regulator's (STUK) experiences on regulatory oversight of the enlargement of a spent fuel interim storage. An overview of the current situation of spent fuel management in Finland will also be given. In addition, the planned modifications and requirements set for spent fuel storages due to the Fukushima accident are discussed. In Finland, there are four operating reactors, one under construction and two reactors that have a Council of State's Decision-in-Principle to proceed with the planning and licensing of a new reactor. In Olkiluoto, the two operating ASEA-Atom BWR units and the Areva EPR under construction have a shared interim storage for the spent fuel. The storage was designed and constructed in 1980's. The option for enlarging the storage was foreseen in the original design. Considering three operating units to produce their spent fuel and the final disposal to begin in 2022, extra space in the spent fuel storage is estimated to be needed in around 2014. The operator decided to double the number of the spent fuel pools of the storage and the construction began in 2010. The capacity of the enlarged spent fuel storage is considered to be sufficient for the three Olkiluoto units. The enlargement of the interim storage was included in Olkiluoto NPP 1 and 2 operating license. The licensing of the enlargement was conducted as a major plant modification. The operator needed the approval from STUK to conduct the enlargement. Prior to the construction of this modification, the operator was required to submit the similar documentation as needed for applying for the construction license of a nuclear facility. When conducting changes in an old nuclear facility, the new safety requirements have to be followed. The major challenge in the designing the enlargement of the spent fuel storage was to modify it to withstand a large airplane crash. The operator chose to cover the pools with protecting slabs and also to

Vibrational lifetimes of protein amide modes

International Nuclear Information System (INIS)

Peterson, K.A.; Rella, C.A.

1995-01-01

Measurement of the lifetimes of vibrational modes in proteins has been achieved with a single frequency infrared pump-probe technique using the Stanford Picosecond Free-electron Laser, These are the first direct measurements of vibrational dynamics in the polyamide structure of proteins. In this study, modes associated with the protein backbone are investigated. Results for the amide I band, which consists mainly of the stretching motion of the carbonyl unit of the amide linkage, show that relaxation from the first vibrational excited level (v=1) to the vibrational ground state (v=0) occurs within 1.5 picoseconds with apparent first order kinetics. Comparison of lifetimes for myoglobin and azurin, which have differing secondary structures, show a small but significant difference. The lifetime for the amide I band of myoglobin is 300 femtoseconds shorter than for azurin. Further measurements are in progress on other backbone vibrational modes and on the temperature dependence of the lifetimes. Comparison of vibrational dynamics for proteins with differing secondary structure and for different vibrational modes within a protein will lead to a greater understanding of energy transfer and dissipation in biological systems. In addition, these results have relevance to tissue ablation studies which have been conducted with pulsed infrared lasers. Vibrational lifetimes are necessary for calculating the rate at which the energy from absorbed infrared photons is converted to equilibrium thermal energy within the irradiated volume. The very fast vibrational lifetimes measured here indicate that mechanisms which involve direct vibrational up-pumping of the amide modes with consecutive laser pulses, leading to bond breakage or weakening, are not valid

A study on the safety of spent fuel management. Radioactive source term modelling

Energy Technology Data Exchange (ETDEWEB)

Chun, Kwan Sik; Lee, Hoo Keun; Park, Keun Il; Hwoang, Jung Ki; Chung, Choong Hwan [Korea Atomic Energy Research Inst., Daeduk (Korea, Republic of)

1992-02-01

The types and probabilities of events which may occur during the process of reception, transfer and storage of spent fuels in an away-from-reactor (AFR) spent fuel storage facility were analyzed in order to calculate the amount of radioactive material released to operation area and atmosphere, and the basic model for predicting the radioactive source-term under normal and abnormal operations were developed. Also, oxidation and dissolution of U0{sub 2} pellet was investigated to estimate the amount of radioactive materials released from spent fuel and the release characteristics of radionuclides from defected spent fuel rods was analyzed. Basic information using FIRAC code to analyze the ventilation system during fire accident was prepared and FIRIN was detached from FIRAC modified to simulate the compartment fire by personal computer. (Author).

Results and Systematic Studies of the UCN Lifetime Experiment at NIST

Science.gov (United States)

Huffer, Craig Reeves

The neutron beta-decay lifetime is important in understanding weak interactions in the framework of the Standard Model, and it is an input to nuclear astrophysics and Big Bang Nucleosynthesis. Current measurements of the neutron beta-decay lifetime disagree, which has motivated additional experiments that are sensitive to different sets of systematic effects. An effort continues at the NIST Center for Neutron Research (NCNR) to improve the statistical and systematic limitations of an experiment to measure the neutron beta-decay lifetime using magnetically trapped UCN. In the experiment, a monoenergetic 0:89 nm cold neutron is incident on a superfluid 4He target within the minimum field region of an Ioffe type magnetic trap. Some of the neutrons are subsequently downscattered by single phonons in the helium to low energies (≈ 200 neV), and those in the appropriate spin state become trapped. The inverse process, upscattering of UCN, is suppressed by the low phonon density in the analysis, data, and systematics will be discussed. After accounting for the systematic effects the measured lifetime disagrees with the current PDG mean neutron beta-decay lifetime by about 9 of our standard deviations, which is a strong indication of unaccounted for systematic effects. Additional 3He contamination will be shown to be the most likely candidate for the additional systematic shift, which motivated the commissioning and initial operation of a heat flush purifier for purifying additional 4He. This work ends with a description of the 4He purifier and its performance.

Real-time monitoring of luminescent lifetime changes of PtOEP oxygen sensing film with LED/photodiode-based time-domain lifetime device.

Science.gov (United States)

Ji, Shaomin; Wu, Wanhua; Wu, Yubo; Zhao, Taiyang; Zhou, Fuke; Yang, Yubin; Zhang, Xin; Liang, Xiaofen; Wu, Wenting; Chi, Lina; Wang, Zhonggang; Zhao, Jianzhang

2009-05-01

A cost-effective LED/photodiode(PD)-based time-domain luminescent lifetime measuring device with rugged electronics and simplified algorithms was assembled and successfully used to characterize oxygen sensing films, by continuously monitoring phosphorescence lifetime changes of phosphorescent platinum octaethylporphyrin (PtOEP) in cardo poly(aryl ether ketone) polymer (IMPEK-C) vs. variation of the oxygen partial pressure in a gas mixture (O(2)/N(2)). The results determined by both phosphorescence lifetime and intensity monitoring were compared and the lifetime mode gave results which are in good agreement with the intensity mode. The lifetime-based linear Stern-Volmer plot indicates that the PtOEP molecules are nearly homogeneously distributed in the sensing film. The phosphorescent lifetime of the PtOEP film changes from 75 micros in neat N(2) to less than 2 micros in neat O(2). The sensing system (by combination of the PtOEP sensing film with the home-assembled lifetime device) gives a high lifetime-based O(2) sensing resolution, e.g. about 2 micros Torr(-1) for low O(2) concentration (below 3.5% O(2), V/V). This feasible lifetime device configuration is affordable to most sensor laboratories and the device may facilitate the study of O(2) sensing material with the continuous lifetime monitoring method.

Developing Spent Fuel Assembly for Advanced NDA Instrument Calibration - NGSI Spent Fuel Project

Energy Technology Data Exchange (ETDEWEB)

Hu, Jianwei [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gauld, Ian C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Banfield, James [GE Hitachi Nuclear Energy, Wilmington, NC (United States); Skutnik, Steven [Univ. of Tennessee, Knoxville, TN (United States)

2014-02-01

This report summarizes the work by Oak Ridge National Laboratory to investigate the application of modeling and simulation to support the performance assessment and calibration of the advanced nondestructive assay (NDA) instruments developed under the Next Generation Safeguards Initiative Spent Fuel (NGSI-SF) Project. Advanced NDA instrument calibration will likely require reference spent fuel assemblies with well-characterized nuclide compositions that can serve as working standards. Because no reference spent fuel standard currently exists, and the practical ability to obtain direct measurement of nuclide compositions using destructive assay (DA) measurements of an entire fuel assembly is prohibitive in the near term due to the complexity and cost of spent fuel experiments, modeling and simulation will be required to construct such reference fuel assemblies. These calculations will be used to support instrument field tests at the Swedish Interim Storage Facility (Clab) for Spent Nuclear Fuel.

Charmed particle lifetimes

International Nuclear Information System (INIS)

Rosner, J.L.

1979-01-01

Conventional estimates are reviewed for charmed particle lifetimes. Free-quark models give values of (a few) x 10 -13 sec to (a few) x 10 -12 sec. The shorter of these values also follows from an extrapolation based on D → Ke/sup nu/. Possible differences among the lifetimes and production rates of D 0 , D + , F + , C 0 + , the heavy lepton tau, and the fifth quark b are discussed. Extreme values of mixing angles in a six-quark model could extend charmed particle lifetimes by a factor of at most three from the above estimates, while shorter lifetimes than those predicted could occur for some species like D 0 or F + if their nonleptonic decays were enhanced. The predictions are discussed in the light of some current experimental results, and it is estimated that sigma(pp → charm) approx. = 10 μb at 400 GeV/c. 95 references

Safety case for the disposal of spent nuclear fuel at Olkiluoto - Synthesis 2012

International Nuclear Information System (INIS)

2012-12-01

TURVA-2012 is Posiva's safety case in support of the Preliminary Safety Analysis Report (PSAR 2012) and application for a construction licence for a spent nuclear fuel repository. Consistent with the Government Decisions-in- Principle, this foresees a repository developed in bedrock at the Olkiluoto site according to the KBS-3 method, designed to accept spent nuclear fuel from the lifetime operations of the Olkiluoto and Loviisa reactors. Synthesis 2012 presents a synthesis of Posiva Oy's Safety Case 'TURVA-2012' portfolio. It summarises the design basis for the repository at the Olkiluoto site, the assessment methodology and key results of performance and safety assessments. It brings together all the lines of argument for safety, evaluation of compliance with the regulatory requirements, and statement of confidence in long-term safety and Posiva's safety analyses. The TURVA-2012 safety case demonstrates that the proposed repository design provides a safe solution for the disposal of spent nuclear fuel, and that the performance and safety assessments are fully consistent with all the legal and regulatory requirements related to long-term safety as set out in Government Decree 736/2008 and in guidance from the nuclear regulator - the STUK. Moreover, Posiva considers that the level of confidence in the demonstration of safety is appropriate and sufficient to submit the construction licence application to the authorities. The assessment of long-term safety includes uncertainties, but these do not affect the basic conclusions on the long-term safety of the repository. (orig.)

The association of lifetime insight and cognition in psychosis.

Science.gov (United States)

Sánchez-Torres, Ana M; Zarzuela, Amalia; Peralta, Victor; Cuesta, Manuel J

2015-03-01

Poor insight has been related to poor course in psychosis. However, the role of cognition in insight remains unclear. The aim of this study was to examine the influence of cognition and lifetime psychopathological dimensions on insight in psychosis. We followed up 42 patients with psychotic disorders over 10years. Lifetime psychopathological dimensions and cognitive performance were assessed. Patients were divided into two groups by lifetime patterns of insight and compared with 42 healthy volunteers. Lower IQ and poorer social cognition were associated with higher risks of poorer lifetime insight of feeling ill and global insight respectively. Lifetime negative symptoms were associated with a higher risk of poorer lifetime insight into symptoms. Lifetime lack of insight is independent of cognitive impairment in specific domains, except for social cognition. Higher IQ may contribute to better lifetime awareness of illness, while better ability to manage emotions is involved in lifetime global insight. Copyright © 2014 Elsevier B.V. All rights reserved.

The study of synthetic food dyes by positron annihilation lifetime spectroscopy.

Science.gov (United States)

Pivtsaev, A. A.; Razov, V. I.

2015-06-01

By method of positron annihilation lifetime spectroscopy (PALS), substances are food dyes were studied: E-102 (Tartrazine), E-124 (Ponso 4R), E 132 (Indigo carmine), E-133 (Brilliant Blue), E-151 (Black Shiny). They are examined for the presence of carcinogenic properties. The difference between dyes having explicit carcinogenic properties and mutagenic properties (non-explicit carcinogens) is established.

Safety aspects of dry spent fuel storage and spent fuel management

International Nuclear Information System (INIS)

Botsch, W.; Smalian, S.; Hinterding, P.; Voelzke, H.; Wolff, D.; Kasparek, E.

2014-01-01

The storage of spent nuclear fuel (SF) and high-level radioactive waste (HLW) must conform to safety requirements. Safety aspects like safe enclosure of radioactive materials, safe removal of decay heat, nuclear criticality safety and avoidance of unnecessary radiation exposure must be achieved throughout the storage period. The implementation of these safety requirements can be achieved by dry storage of SF and HLW in casks as well as in other systems such as dry vault storage systems or spent fuel pools, where the latter is neither a dry nor a passive system. In Germany dual purpose casks for SF or HLW are used for safe transportation and interim storage. TUV and BAM, who work as independent experts for the competent authorities, present the storage licensing process including sites and casks and inform about spent nuclear fuel management and issues concerning dry storage of spent nuclear fuel, based on their long experience in these fields (authors)

Safeguardability of advanced spent fuel conditioning process

Energy Technology Data Exchange (ETDEWEB)

Li, T. K. (Tien K.); Lee, S. Y. (Sang Yoon); Burr, Tom; Russo, P. A. (Phyllis A.); Menlove, Howard O.; Kim, H. D.; Ko, W. I. (Won Il); Park, S. W.; Park, H. S.

2004-01-01

The Advanced Spent Fuel Conditioning Process (ACP) is an electro-metallurgical treatment technique to convert oxide-type spent nuclear fuel into a metallic form. The Korea Atomic Energy Research Institute (KAERI) has been developing this technology since 1977 for the purpose of spent fuel management and is planning to perform a lab-scale demonstration in 2006. By using of this technology, a significant reduction of the volume and heat load of spent fuel is expected, which would lighten the burden of final disposal in terms of disposal size, safety and economics. In the framework of collaboration agreement to develop the safeguards system for the ACP, a joint study on the safeguardability of the ACP technology has been performed by the Los Alamos National Laboratory (LANL) and the KAERI since 2002. In this study, the safeguardability of the ACP technology was examined for the pilot-scale facility. The process and material flows were conceptually designed, and the uncertainties in material accounting were estimated with international target values.

The spent fuel safety experiment

International Nuclear Information System (INIS)

Harmms, G.A.; Davis, F.J.; Ford, J.T.

1995-01-01

The Department of Energy is conducting an ongoing investigation of the consequences of taking fuel burnup into account in the design of spent fuel transportation packages. A series of experiments, collectively called the Spent Fuel Safety Experiment (SFSX), has been devised to provide integral benchmarks for testing computer-generated predictions of spent fuel behavior. A set of experiments is planned in which sections of unirradiated fuel rods are interchanged with similar sections of spent PWR fuel rods in a critical assembly. By determining the critical size of the arrays, one can obtain benchmark data for comparison with criticality safety calculations. The integral reactivity worth of the spent fuel can be assessed by comparing the measured delayed critical fuel loading with and without spent fuel. An analytical effort to model the experiments and anticipate the core loadings required to yield the delayed critical conditions runs in parallel with the experimental effort

Studies of the Influence of Water Radiolysis to the Spent Fuel Matrix Dissolution Process

International Nuclear Information System (INIS)

Quinones, J.; Serrano, J.

2001-01-01

The disposal of high level radioactive waste in geological deep repositories relies on the long term stability of spent fuel matrix, which must be assured for thousands of years. One of these factors considered within the studies of performance assessment on spent fuel under final repository conditions is the effect of the radiation on its leaching behaviour. Due to the radiation from spent fuel can modify some properties of both solid phase and leachant and therefore it would alter the chemical behaviour of the near field. Particularizing in the effect of the radiation on the leachant, it will cause generation of radiolytic species that could change the redox potential of the environment and therefore may bring on variations in the leaching process. In this work, we compiled the leaching experiments performed in an irradiation facility (Nayade), in order to emulate γ radiation field of a spent fuel at different cooling times. Initial dose rate used was 0.014 (Gy/s) using source of ''60 Co. The spent fuel chemical analogue utilised was SIMFUEL (natural UO 2 doped with non-radioactive elements simulating fission products) and the leachant selected were saline and granite bentonite waters both under initial anoxic conditions. Preliminary results indicate that radiation produces an increase of the uranium dissolution rate, being the concentrations measured close to those obtained in oxic atmosphere without radiation field. In addition the solubility solid phases from experimental conditions were calculated, for both granite bentonite water and 5 m NaCl media. On the other hand, a tentative approach to model the role of γ radiolysis in these SIMFUEL tests has been carried out as well. (Author)

Study of positron annihilation lifetime spectroscopy in carbon black-filled HDPE composite

CERN Document Server

Zhang Xian Feng; Zhou Xian Yi; Weng Hu Imin; Ye Bang Jiao; Han Rong Dian; Jia Shao Jin; Zhang Zhi Cheng

2002-01-01

The variation of the electrical conductivity of high density polyethylene (HDPE) with the carbon black (CB) content was studied using positron annihilation lifetime spectroscopy (PALS) and free-volume model, the crystallinity of HDPE/CB composite and 'percolation' effect were discussed with measurements of conductivity and DSC test

Gut Microbiome Associates With Lifetime Cardiovascular Disease Risk Profile Among Bogalusa Heart Study Participants.

Science.gov (United States)

Kelly, Tanika N; Bazzano, Lydia A; Ajami, Nadim J; He, Hua; Zhao, Jinying; Petrosino, Joseph F; Correa, Adolfo; He, Jiang

2016-09-30

Few studies have systematically assessed the influence of gut microbiota on cardiovascular disease (CVD) risk. To examine the association between gut microbiota and lifetime CVD risk profile among 55 Bogalusa Heart Study participants with the highest and 57 with the lowest lifetime burdens of CVD risk factors. 16S ribosomal RNA sequencing was conducted on microbial DNA extracted from stool samples of the Bogalusa Heart Study participants. α Diversity, including measures of richness and evenness, and individual genera were tested for associations with lifetime CVD risk profile. Multivariable regression techniques were used to adjust for age, sex, and race (model 1), along with body mass index (model 2) and both body mass index and diet (model 3). In model 1, odds ratios (95% confidence intervals) for each SD increase in richness, measured by the number of observed operational taxonomic units, Chao 1 index, and abundance-based coverage estimator, were 0.62 (0.39-0.99), 0.61 (0.38-0.98), and 0.63 (0.39-0.99), respectively. Associations were consistent in models 2 and 3. Four genera were enriched among those with high versus low CVD risk profile in all models. Model 1 P values were 2.12×10(-3), 7.95×10(-5), 4.39×10(-4), and 1.51×10(-4) for Prevotella 2, Prevotella 7, Tyzzerella, and Tyzzerella 4, respectively. Two genera were depleted among those with high versus low CVD risk profile in all models. Model 1 P values were 2.96×10(-6) and 1.82×10(-4) for Alloprevotella and Catenibacterium, respectively. The current study identified associations of overall microbial richness and 6 microbial genera with lifetime CVD risk. © 2016 American Heart Association, Inc.

Thirty years of transport package development for spent fuels

International Nuclear Information System (INIS)

Cory, A.R.

2005-01-01

By June 2005, when shipments of spent fuel for reprocessing from Germany are concluded, BNFL flask types will have been responsible for transporting more than 2000 tonnes of heavy metal in Europe in the form of spent fuel. Several thousand more tonnes of spent fuel have been transported by sea from Japan over the last thirty years. The design of spent fuel packages has not stood still for that time. In order to anticipate the changing needs of the nuclear power generation industry, advances have been made both in package design and analysis. Thirty years ago spent fuel burnup and initial enrichment were considerably lower, which was reflected in the different demands placed on the shielding design of packages, and in the design of the internal basket to separate the fuel assemblies. Technical development of both 'wet' (water-filled cavity) and 'dry' packages has progressed in parallel, and the relative merits and peculiarities of each type is explored. BNFL has considerable experience in the operation of both types, and is well placed to comment on practical and functional issues associated with both types. While there have been certain evolutionary changes affecting package design, there have also been more significant changes in the Design Safety Case. These have sometimes been necessary to meet changes in IAEA Regulations, or the challenges posed by the regulators themselves. In other cases advantage has been taken of improvements in analytical techniques to demonstrate increased margins of operational safety. Where possible these margins have also been increased by other means, such as taking advantage of commercial trends to reduce package thermal loads. A key factor over the last thirty years has been the increasing influence of the Regulating Authorities and the development of the IAEA Regulations. The various Competent Authorities now tend to have a higher proportion of technical experts, often recruited from the nuclear industry, and are thus more able to

Disposal of spent nuclear fuel

International Nuclear Information System (INIS)

1979-12-01

This report addresses the topic of the mined geologic disposal of spent nuclear fuel from Pressurized Water Reactors (PWR) and Boiling Water Reactors (BWR). Although some fuel processing options are identified, most of the information in this report relates to the isolation of spent fuel in the form it is removed from the reactor. The characteristics of the waste management system and research which relate to spent fuel isolation are discussed. The differences between spent fuel and processed HLW which impact the waste isolation system are defined and evaluated for the nature and extent of that impact. What is known and what needs to be determined about spent fuel as a waste form to design a viable waste isolation system is presented. Other waste forms and programs such as geologic exploration, site characterization and licensing which are generic to all waste forms are also discussed. R and D is being carried out to establish the technical information to develop the methods used for disposal of spent fuel. All evidence to date indicates that there is no reason, based on safety considerations, that spent fuel should not be disposed of as a waste

Studies of energy levels and lifetimes in neutral and ionized light atoms

International Nuclear Information System (INIS)

Huldt, S.

1980-05-01

The spectrum of singly ionized Titanium has been analysed by photographic spectral recordings of the light from a hollow- cathod. 1240 classified lines in the region 1200 A - 11000 A and 202 term values are reported. Lifetimes of the 3p 5 5p levels in neutral Argon have been measured by the High-frequency-Deflection technique considering the trapping of radiation from the excited 3p 5 4s level. Energy levels and lifetimes of excited states have been studied with the beam-foil method for selected ions in the atomic number range 7 - 30. Influence of transition probabilities caused by hyper-fine interaction for low members of the Helium iso-electronic sequence i verified. The oscillator strength for the inter-combination transition ls 2 1S 0 -1s3p 3 p 1 is measured in Beryllium-like Nitrogen, Oxygen and Fluorine. Accurate determinations of lifetimes for some of the lowest excited levels in Si I - Si IV and Zn II are reported. A large fraction of circularly polarized light is seen in the 0 VI n=6-7 hydrogenic transition when a 4 MeV beam of oxygen was passed through a tilted carbon foil. (author)

Collective processing device for spent fuel

International Nuclear Information System (INIS)

Irie, Hiroaki; Taniguchi, Noboru.

1996-01-01

The device of the present invention comprises a sealing vessel, a transporting device for transporting spent fuels to the sealing vessel, a laser beam cutting device for cutting the transported spent fuels, a dissolving device for dissolving the cut spent fuels, and a recovering device for recovering radioactive materials from the spent fuels during processing. Reprocessing treatments comprising each processing of dismantling, shearing and dissolving are conducted in the sealing vessel can ensure a sealing barrier for the radioactive materials (fissionable products and heavy nuclides). Then, since spent fuels can be processed in a state of assemblies, and the spent fuels are easily placed in the sealing vessel, operation efficiency is improved, as well as operation cost is saved. Further, since the spent fuels can be cut by a remote laser beam operation, there can be prevented operator's exposure due to radioactive materials released from the spent fuels during cutting operation. (T.M.)

Site-selection studies for final disposal of spent fuel in Finland

International Nuclear Information System (INIS)

Vuorela, P.; Aeikaes, T.

1984-02-01

In the management of waste by the Industrial Power Company Ltd. (TVO) preparations are being made for the final disposal of unprocessed spent fuel into the Finnish bedrock. The site selection program will advance in three phases. The final disposal site must be made at the latest by the end of the year 2000, in accordance with a decision laid down by the Finnish Government. In the first phase, 1983-85, the main object is to find homogeneous stable bedrock blocks surrounded by fracture zones located at a safe distance from the planned disposal area. The work usually starts with a regional structural analysis of mosaics of Landsat-1 winter and summer imagery. Next an assortment of different maps, which cover the whole country, is used. Technical methods for geological and hydrogeological site investigations are being developed during the very first phase of the studies, and a borehole 1000 meters deep will be made in southwestern Finland. Studies for the final disposal of spent fuel or high-level reprocessing waste have been made since 1974 in Finland. General suitability studies of the bedrock have been going on since 1977. The present results indicate that suitable investigation areas for the final disposal of highly active waste can be found in Finland

Global Spent Fuel Logistics Systems Study (GSFLS). Volume 2. GSFLS visit findings and evaluations. Interim report

International Nuclear Information System (INIS)

1978-01-01

This report is a part of the interim report documentation for the Global Spent Fuel Logistics System (GSFLS) study. This report describes a global framework that evaluates spent fuel disposition requirements, influencing factors and strategies. A broad sampling of foreign governmental officials, electric utility spokesmen and nuclear power industry officials responsible for GSFLS policies, plans and programs were surveyed as to their views with respect to national and international GSFLS related considerations. The results of these GSFLS visit findings are presented herein. These findings were then evaluated in terms of technical, institutional and legal/regulatory implications. The GSFLS evaluations, in conjunction with perceived US spent fuel objectives, formed the basis for selecting a set of GSFLS strategies which are reported herein

Criticality safety studies involved in actions to improve conditions for storing 'RA' research reactor spent fuel

International Nuclear Information System (INIS)

Matausek, M.; Marinkovic, N.

1998-01-01

A project has recently been initiated by the VINCA Institute of Nuclear Sciences to improve conditions in the spent fuel storage pool at the 6.5 MW research reactor RA, as well as to consider transferring this spent fuel into a new dry storage facility built for the purpose. Since quantity and contents of fissile material in the spent fuel storage at the RA reactor are such that possibility of criticality accident can not be a priori excluded, according to standards and regulations for handling fissile material outside a reactor, before any action is undertaken subcriticality should be proven under normal, as well as under credible abnormal conditions. To perform this task, comprehensive nuclear criticality safety studies had to be performed. (author)

Global Spent Fuel Logistics Systems Study (GSFLS). Volume 2. GSFLS visit findings and evaluations. Interim report

Energy Technology Data Exchange (ETDEWEB)

None

1978-01-31

This report is a part of the interim report documentation for the Global Spent Fuel Logistics System (GSFLS) study. This report describes a global framework that evaluates spent fuel disposition requirements, influencing factors and strategies. A broad sampling of foreign governmental officials, electric utility spokesmen and nuclear power industry officials responsible for GSFLS policies, plans and programs were surveyed as to their views with respect to national and international GSFLS related considerations. The results of these GSFLS visit findings are presented herein. These findings were then evaluated in terms of technical, institutional and legal/regulatory implications. The GSFLS evaluations, in conjunction with perceived US spent fuel objectives, formed the basis for selecting a set of GSFLS strategies which are reported herein.

Engineering study for the treatment of spent ion exchange resin resulting from nuclear process applications

International Nuclear Information System (INIS)

Place, B.G.

1990-09-01

This document is an engineering study of spent ion exchange resin treatment processes with the purpose of identifying one or more suitable treatment technologies. Classifications of waste considered include all classes of low-level waste (LLW), mixed LLW, transuranic (TRU) waste, and mixed TRU waste. A total of 29 process alternatives have been evaluated. Evaluation parameters have included economic parameters (both total life-cycle costs and capital costs), demonstrated operability, environmental permitting, operational availability, waste volume reduction, programmatic consistency, and multiple utilization. The results of this study suggest that there are a number of alternative process configurations that are suitable for the treatment of spent ion exchange resin. The determinative evaluation parameters were economic variables (total life-cycle cost or capital cost) and waste volume reduction. Immobilization processes are generally poor in volume reduction. Thermal volume reduction processes tend to have high capital costs. There are immobilization processes and thermal volume reduction processes that can treat all classifications of spent ion exchange resin likely to be encountered. 40 refs., 19 figs., 17 tabs

The study of synthetic food dyes by positron annihilation lifetime spectroscopy

International Nuclear Information System (INIS)

Pivtsaev, A A; Razov, V I

2015-01-01

By method of positron annihilation lifetime spectroscopy (PALS), substances are food dyes were studied: E-102 (Tartrazine), E-124 (Ponso 4R), E 132 (Indigo carmine), E-133 (Brilliant Blue), E-151 (Black Shiny). They are examined for the presence of carcinogenic properties. The difference between dyes having explicit carcinogenic properties and mutagenic properties (non-explicit carcinogens) is established. (paper)

Reliability-based assessment of polyethylene pipe creep lifetime

International Nuclear Information System (INIS)

Khelif, Rabia; Chateauneuf, Alaa; Chaoui, Kamel

2007-01-01

Lifetime management of underground pipelines is mandatory for safe hydrocarbon transmission and distribution systems. The use of high-density polyethylene tubes subjected to internal pressure, external loading and environmental variations requires a reliability study in order to define the service limits and the optimal operating conditions. In service, the time-dependent phenomena, especially creep, take place during the pipe lifetime, leading to significant strength reduction. In this work, the reliability-based assessment of pipe lifetime models is carried out, in order to propose a probabilistic methodology for lifetime model selection and to determine the pipe safety levels as well as the most important parameters for pipeline reliability. This study is enhanced by parametric analysis on pipe configuration, gas pressure and operating temperature

Reliability-based assessment of polyethylene pipe creep lifetime

Energy Technology Data Exchange (ETDEWEB)

Khelif, Rabia [LaMI-UBP and IFMA, Campus de Clermont-Fd, Les Cezeaux, BP 265, 63175 Aubiere Cedex (France); LR3MI, Departement de Genie Mecanique, Universite Badji Mokhtar, BP 12, Annaba 23000 (Algeria)], E-mail: rabia.khelif@ifma.fr; Chateauneuf, Alaa [LGC-University Blaise Pascal, Campus des Cezeaux, BP 206, 63174 Aubiere Cedex (France)], E-mail: alaa.chateauneuf@polytech.univ-bpclermont.fr; Chaoui, Kamel [LR3MI, Departement de Genie Mecanique, Universite Badji Mokhtar, BP 12, Annaba 23000 (Algeria)], E-mail: chaoui@univ-annaba.org

2007-12-15

Lifetime management of underground pipelines is mandatory for safe hydrocarbon transmission and distribution systems. The use of high-density polyethylene tubes subjected to internal pressure, external loading and environmental variations requires a reliability study in order to define the service limits and the optimal operating conditions. In service, the time-dependent phenomena, especially creep, take place during the pipe lifetime, leading to significant strength reduction. In this work, the reliability-based assessment of pipe lifetime models is carried out, in order to propose a probabilistic methodology for lifetime model selection and to determine the pipe safety levels as well as the most important parameters for pipeline reliability. This study is enhanced by parametric analysis on pipe configuration, gas pressure and operating temperature.

Radiological impacts of spent nuclear fuel management options

International Nuclear Information System (INIS)

Riotte, H.; Lazo, T.; Mundigl, S.

2000-01-01

An important technical study on radiological impacts of spent nuclear fuel management options, recently completed by the NEA, is intended to facilitate informed international discussions on the nuclear fuel cycle. The study compares the radiological impacts on the public and on nuclear workers resulting from two approaches to handling spent fuel from nuclear power plants: - the reprocessing option, that includes the recycling of spent uranium fuel, the reuse of the separated plutonium in MOX fuel, and the direct disposal of spent MOX fuel; and the once-through option, with no reprocessing of spent fuel, and its direct disposal. Based on the detailed research of a group of 18 internationally recognised experts, under NEA sponsorship, the report concludes that: The radiological impacts of both the reprocessing and the non-reprocessing fuel cycles studied are small, well below any regulatory dose limits for the public and for workers, and insignificantly low as compared with exposures caused by natural radiation. The difference in the radiological impacts of the two fuel cycles studied does not provide a compelling argument in favour of one option or the other. The study also points out that other factors, such as resource utilisation efficiency, energy security, and social and economic considerations would tend to carry more weight than radiological impacts in decision-making processes. (authors)

Probability of spent fuel transportation accidents

International Nuclear Information System (INIS)

McClure, J.D.

1981-07-01

The transported volume of spent fuel, incident/accident experience and accident environment probabilities were reviewed in order to provide an estimate of spent fuel accident probabilities. In particular, the accident review assessed the accident experience for large casks of the type that could transport spent (irradiated) nuclear fuel. This review determined that since 1971, the beginning of official US Department of Transportation record keeping for accidents/incidents, there has been one spent fuel transportation accident. This information, coupled with estimated annual shipping volumes for spent fuel, indicated an estimated annual probability of a spent fuel transport accident of 5 x 10 -7 spent fuel accidents per mile. This is consistent with ordinary truck accident rates. A comparison of accident environments and regulatory test environments suggests that the probability of truck accidents exceeding regulatory test for impact is approximately 10 -9 /mile

Loss of spent fuel pool cooling PRA: Model and results

International Nuclear Information System (INIS)

Siu, N.; Khericha, S.; Conroy, S.; Beck, S.; Blackman, H.

1996-09-01

This letter report documents models for quantifying the likelihood of loss of spent fuel pool cooling; models for identifying post-boiling scenarios that lead to core damage; qualitative and quantitative results generated for a selected plant that account for plant design and operational practices; a comparison of these results and those generated from earlier studies; and a review of available data on spent fuel pool accidents. The results of this study show that for a representative two-unit boiling water reactor, the annual probability of spent fuel pool boiling is 5 x 10 -5 and the annual probability of flooding associated with loss of spent fuel pool cooling scenarios is 1 x 10 -3 . Qualitative arguments are provided to show that the likelihood of core damage due to spent fuel pool boiling accidents is low for most US commercial nuclear power plants. It is also shown that, depending on the design characteristics of a given plant, the likelihood of either: (a) core damage due to spent fuel pool-associated flooding, or (b) spent fuel damage due to pool dryout, may not be negligible

Measurements of heavy quark and lepton lifetimes

International Nuclear Information System (INIS)

Jaros, J.A.

1985-02-01

The PEP/PETRA energy range has proved to be well-suited for the study of the lifetimes of hadrons containing the b and c quarks and the tau lepton for several reasons. First, these states comprise a large fraction of the total interaction rate in e + e - annihilation and can be cleanly identified. Second, the storage rings have operated at high luminosity and so produced these exotic states copiously. And finally, thanks to the interplay of the Fermi coupling strength, the quark and lepton masses, and the beam energy, the expected decay lengths are in the 1/2 mm range and so are comparatively easy to measure. This pleasant coincidence of cleanly identified and abundant signal with potentially large effects has made possible the first measurements of two fundamental weak couplings, tau → nu/sub tau/W and b → cW. These measurements have provided a sharp test of the standard model and allowed, for the first time, the full determination of the magnitudes of the quark mixing matrix. This paper reviews the lifetime studies made at PEP during the past year. It begins with a brief review of the three detectors, DELCO, MAC and MARK II, which have reported lifetime measurements. Next it discusses two new measurements of the tau lifetime, and briefly reviews a measurement of the D 0 lifetime. Finally, it turns to measurements of the B lifetime, which are discussed in some detail. 18 references, 14 figures, 1 table

Precision lifetime measurements

International Nuclear Information System (INIS)

Tanner, C.E.

1994-01-01

Precision measurements of atomic lifetimes provide important information necessary for testing atomic theory. The authors employ resonant laser excitation of a fast atomic beam to measure excited state lifetimes by observing the decay-in-flight of the emitted fluorescence. A similar technique was used by Gaupp, et al., who reported measurements with precisions of less than 0.2%. Their program includes lifetime measurements of the low lying p states in alkali and alkali like systems. Motivation for this work comes from a need to test the atomic many-body-perturbation theory (MBPT) that is necessary for interpretation of parity nonconservation experiments in atomic cesium. The authors have measured the cesium 6p 2 P 1/2 and 6p 2 P 3/2 state lifetimes to be 34.934±0.094 ns and 30.499±0.070 ns respectively. With minor changes to the apparatus, they have extended their measurements to include the lithium 2p 2 P 1/2 and 2p 2 P 3/2 states

Improved b lifetime measurement from MAC

International Nuclear Information System (INIS)

Ford, W.T.

1984-03-01

Two recent publications, from the MAC and Mark II collaborations, have reported the somewhat surprising result that the lifetime of particles made up of b quarks is in the 1 to 2 picosecond range, or somewhat longer than the lifetimes of charm particles. Although the charm decays are favored transitions while those of b particles depend upon off-diagonal elements of the weak flavor mixing matrix, the smallness of the b decay rates in face of the large available phase space indicates that the off-diagonal elements are indeed very small. The possibility for complete determination of the mixing matrix was brought significantly nearer by the availability of the lifetime information; what is needed now is to reduce the uncertainty of the measurements, which was about 33% for both experiments. We describe here an extension of the b lifetime study with the MAC detector, incorporating some new data and improvements in the analysis. 12 references

Spent fuel management overview: a global perspective

International Nuclear Information System (INIS)

Bonne, A.; Crijns, M.J.; Dyck, P.H.; Fukuda, K.; Mourogov, V.M.

1999-01-01

The paper defines the main spent fuel management strategies and options, highlights the challenges for spent fuel storage and gives an overview of the regional balances of spent fuel storage capacity and spent fuel arising. The relevant IAEA activities in the area of spent fuel management are summarised. (author)

Low-temperature positron-lifetime studies of proton-irradiated silicon

DEFF Research Database (Denmark)

Mäkinen, S.; Rajainmäki, H.; Linderoth, Søren

1990-01-01

The positron-lifetime technique has been used to identify defects created in high-purity single-crystal silicon by irradiation with 12-MeV protons at 15 K, and the evolution of the defects has been studied by subsequent annealings between 20 and 650 K. Two clear annealing steps were seen...... in the samples, the first starting at 100 K and the other at 400 K. The first is suggested to be a result of the migration of free, negatively charged monovacancies, and the second is connected to the annealing of some vacancy-impurity complexes, probably negatively charged vacancy-oxygen pairs. The specific...

Electron irradiated liquid encapsulated Czochralski grown undoped gallium antimonide studied by positron lifetime spectroscopy and photoluminescence

International Nuclear Information System (INIS)

Ma, S K; Lui, M K; Ling, C C; Fung, S; Beling, C D; Li, K F; Cheah, K W; Gong, M; Hang, H S; Weng, H M

2004-01-01

Electron irradiated undoped liquid encapsulated Czochralski (LEC) grown GaSb samples were studied by positron lifetime spectroscopy (PLS) and photoluminescence (PL). In addition to the 315 ps component reported in the previous studies, another defect with a lifetime of 280 ps was also identified in the present electron irradiated samples. The bulk lifetime of the GaSb material was found to be 258 ps. The V Ga,280ps and the V Ga,315ps defects were associated with two independent Ga vacancy related defects having different microstructures. The well known 777 meV PL signal (usually band A) was also observed in the electron irradiated undoped GaSb samples. The band A intensity decreases with increasing electron irradiation dosage and it disappears after the 300 deg. C annealing regardless of the irradiation dosage. The origin of the band A signal is also discussed

Microbial biofilm growth on irradiated, spent nuclear fuel cladding

International Nuclear Information System (INIS)

Bruhn, D.F.; Frank, S.M.; Roberto, F.F.; Pinhero, P.J.; Johnson, S.G.

2009-01-01

A fundamental criticism regarding the potential for microbial influenced corrosion in spent nuclear fuel cladding or storage containers concerns whether the required microorganisms can, in fact, survive radiation fields inherent in these materials. This study was performed to unequivocally answer this critique by addressing the potential for biofilm formation, the precursor to microbial-influenced corrosion, in radiation fields representative of spent nuclear fuel storage environments. This study involved the formation of a microbial biofilm on irradiated spent nuclear fuel cladding within a hot cell environment. This was accomplished by introducing 22 species of bacteria, in nutrient-rich media, to test vessels containing irradiated cladding sections and that was then surrounded by radioactive source material. The overall dose rate exceeded 2 Gy/h gamma/beta radiation with the total dose received by some of the bacteria reaching 5 x 10 3 Gy. This study provides evidence for the formation of biofilms on spent-fuel materials, and the implication of microbial influenced corrosion in the storage and permanent deposition of spent nuclear fuel in repository environments

Lifetime statistics of quantum chaos studied by a multiscale analysis

KAUST Repository

Di Falco, A.

2012-04-30

In a series of pump and probe experiments, we study the lifetime statistics of a quantum chaotic resonator when the number of open channels is greater than one. Our design embeds a stadium billiard into a two dimensional photonic crystal realized on a silicon-on-insulator substrate. We calculate resonances through a multiscale procedure that combines energy landscape analysis and wavelet transforms. Experimental data is found to follow the universal predictions arising from random matrix theory with an excellent level of agreement.

A positron lifetime study of properties of light particles in liquids

International Nuclear Information System (INIS)

Jacobsen, F.M.

1981-04-01

The positron lifetime technique has been used for studying the behaviour of the three light particles: the positron, positronium (Ps) (a bound state of an electron and positron), and excess electron in non-polar liquids. A brief introduction to the subject and a short description of the experimental techniques are given. Further, the principles of the data analyses are discussed in some detail. Positron lifetime measurements have been performed on the liquids: SF 6 , neopentane, hexane, and two viscoelastic organic liquids. The experiments have been performed as function of temperature, e.g., from just above the melting point to above the critical point in the cases of liquid SF 6 and neopentane. In all of the liquids the experimental results show that Ps is formed. The analyses of the lifetime spectra show that the Ps yields as well as the state of Ps in these liquids change with temperature. A detailed discussion of the state of Ps in liquids is given. The present results can be explained fairly well in terms of the Ps bubble model. In liquid SF 6 the experimental results strongly indicate that ortho-Ps can annihilate from two different states. The longest-lived ortho-Ps state seems to be similar to that observed in most liquids while the shortest-lived state seems not to have been observed in any other liquids before. A detailed discussion of the measured Ps yield in liquid neopentane and hexane is given. The Ps yield is interpreted by means of the positron spur model. (author)

Spectroscopy and lifetime of bottom and charm hadrons

International Nuclear Information System (INIS)

F. Ukegawa

2000-01-01

There are several motivations for studying masses and lifetimes of the hadrons containing a heavy quark, either the bottom or the charm quark. First, the mass and the lifetime are fundamental properties of an elementary particle. Second, the spectroscopy of hadrons gives insights into the QCD potential between quarks. In particular, a symmetry exists for heavy hadrons when the heavy quark mass is taken to be infinite, providing a powerful tool to predict and understand properties of those heavy hadrons. Third, studies of the lifetimes of heavy hadrons probe their decay mechanisms. A measurement of the lifetime, or the total decay width, is necessary when the authors extract magnitudes of elements of the Kobayashi-Maskawa matrix. Again, in the limit of an infinite heavy quark mass things become simple and decay of a heavy hadron should be the decay of the heavy quark Q. This leads to a prediction that all hadrons containing the heavy quark Q should have the same lifetime, that of the quark Q. This is far from reality in the case of charm hadrons, where the D + meson lifetime is about 2.5 times longer than the D 0 meson lifetime. Perhaps the charm quark is not heavy enough. The simple quark decay picture should be a better approximation for the bottom hadrons because of the larger b quark mass. On the experimental side, the measurements and knowledge of the heavy hadrons (in particular bottom hadrons) have significantly improved over the last decade, thanks to high statistics data accumulated by various experiments. The authors shall review recent developments in these studies in the remainder of this manuscript

Time Well Spent? Relating Television Use to Children’s Free-Time Activities

Science.gov (United States)

Vandewater, Elizabeth A.; Bickham, David S.; Lee, June H.

2010-01-01

OBJECTIVES This study assessed the claim that children’s television use interferes with time spent in more developmentally appropriate activities. METHODS Data came from the first wave of the Child Development Supplement, a nationally representative sample of children aged 0 to 12 in 1997 (N = 1712). Twenty-four-hour time-use diaries from 1 randomly chosen weekday and 1 randomly chosen weekend day were used to assess children’s time spent watching television, time spent with parents, time spent with siblings, time spent reading (or being read to), time spent doing homework, time spent in creative play, and time spent in active play. Ordinary least squares multiple regression was used to assess the relationship between children’s television use and time spent pursuing other activities. RESULTS Results indicated that time spent watching television both with and without parents or siblings was negatively related to time spent with parents or siblings, respectively, in other activities. Television viewing also was negatively related to time spent doing homework for 7- to 12-year-olds and negatively related to creative play, especially among very young children (younger than 5 years). There was no relationship between time spent watching television and time spent reading (or being read to) or to time spent in active play. CONCLUSIONS The results of this study are among the first to provide empirical support for the assumptions made by the American Academy of Pediatrics in their screen time recommendations. Time spent viewing television both with and without parents and siblings present was strongly negatively related to time spent interacting with parents or siblings. Television viewing was associated with decreased homework time and decreased time in creative play. Conversely, there was no support for the widespread belief that television interferes with time spent reading or in active play. PMID:16452327

Study on increasing spent fuel storage capacity at Juragua NPP

International Nuclear Information System (INIS)

Guerra Valdes, R.; Lopez Aldama, D.; Rodriguez Gual, M.; Garcia Yip, F.

1999-01-01

The delay in decision about the final disposal of the spent fuel, led to longer interim storage. The reracking og the storage pools was an economical and feasible option to increase the storage capacity on the site. Reracking of the storage facility led to the analysis of the new conditions for criticality, shielding, residual heat removal and mechanical loads over the structures. This paper includes a summary of the studies on criticality and dose rate changes in the vicinity of the storage pool of Juragua NPP

Safety case for the disposal of spent nuclear fuel at Olkiluoto - Synthesis 2012

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-12-15

TURVA-2012 is Posiva's safety case in support of the Preliminary Safety Analysis Report (PSAR 2012) and application for a construction licence for a spent nuclear fuel repository. Consistent with the Government Decisions-in- Principle, this foresees a repository developed in bedrock at the Olkiluoto site according to the KBS-3 method, designed to accept spent nuclear fuel from the lifetime operations of the Olkiluoto and Loviisa reactors. Synthesis 2012 presents a synthesis of Posiva Oy's Safety Case 'TURVA-2012' portfolio. It summarises the design basis for the repository at the Olkiluoto site, the assessment methodology and key results of performance and safety assessments. It brings together all the lines of argument for safety, evaluation of compliance with the regulatory requirements, and statement of confidence in long-term safety and Posiva's safety analyses. The TURVA-2012 safety case demonstrates that the proposed repository design provides a safe solution for the disposal of spent nuclear fuel, and that the performance and safety assessments are fully consistent with all the legal and regulatory requirements related to long-term safety as set out in Government Decree 736/2008 and in guidance from the nuclear regulator - the STUK. Moreover, Posiva considers that the level of confidence in the demonstration of safety is appropriate and sufficient to submit the construction licence application to the authorities. The assessment of long-term safety includes uncertainties, but these do not affect the basic conclusions on the long-term safety of the repository. (orig.)

An experimental study on Sodalite and SAP matrices for immobilization of spent chloride salt waste

Science.gov (United States)

Giacobbo, Francesca; Da Ros, Mirko; Macerata, Elena; Mariani, Mario; Giola, Marco; De Angelis, Giorgio; Capone, Mauro; Fedeli, Carlo

2018-02-01

In the frame of Generation IV reactors a renewed interest in pyro-processing of spent nuclear fuel is underway. Molten chloride salt waste arising from the recovering of uranium and plutonium through pyro-processing is one of the problematic wastes for direct application of vitrification or ceramization. In this work, Sodalite and SAP have been evaluated and compared as potential matrices for confinement of spent chloride salt waste coming from pyro-processing. To this aim Sodalite and SAP were synthesized both in pure form and mixed with different glass matrices, i.e. commercially available glass frit and borosilicate glass. The confining matrices were loaded with mixed chloride salts to study their retention capacities with respect to the elements of interest. The matrices were characterized and leached for contact times up to 150 days at room temperature and at 90 °C. SEM analyses were also performed in order to compare the matrix surface before and after leaching. Leaching results are discussed and compared in terms of normalized releases with similar results reported in literature. According to this comparative study the SAP matrix with glass frit binder resulted in the best matrix among the ones studied, with respect to retention capacities for both matrix and spent fuel elements.

Final environmental impact statement: US Spent Fuel Policy. Charge for spent fuel storage

International Nuclear Information System (INIS)

1980-05-01

The United States Government policy relating to nuclear fuel reprocessing, which was announced by President Carter on April 7, 1977, provides for an indefinite deferral of reprocessing, and thus commits light water reactor (LWR) plants to a once-through fuel cycle during that indefinite period. In a subsequent action implementing that policy, the Department of Energy (DOE) on October 18, 1977 announced a spent fuel policy which would enable domestic, and on a selective basis, foreign utilities to deliver spent fuel to the US Government for interim storage and final geologic disposal, and pay the Government a fee for such services. This volume addresses itself to whether the fee charged for these services, by its level or its structure, would have any effect on the environmental impacts of implementing the Spent Fuel Policy itself. This volume thus analyzes the fee and various alternatives to determine the interaction between the fee and the degree of participation by domestic utilities and foreign countries in the proposed spent fuel program for implementing the Spent Fuel Policy. It also analyzes the effect, if any, of the fee on the growth of nuclear power

Studies on Mathematical Models of Wet Adhesion and Lifetime Prediction of Organic Coating/Steel by Grey System Theory.

Science.gov (United States)

Meng, Fandi; Liu, Ying; Liu, Li; Li, Ying; Wang, Fuhui

2017-06-28

A rapid degradation of wet adhesion is the key factor controlling coating lifetime, for the organic coatings under marine hydrostatic pressure. The mathematical models of wet adhesion have been studied by Grey System Theory (GST). Grey models (GM) (1, 1) of epoxy varnish (EV) coating/steel and epoxy glass flake (EGF) coating/steel have been established, and a lifetime prediction formula has been proposed on the basis of these models. The precision assessments indicate that the established models are accurate, and the prediction formula is capable of making precise lifetime forecasting of the coatings.

Positron lifetimes in deformed copper

International Nuclear Information System (INIS)

Hinode, Kenji; Tanigawa, Shoichiro; Doyama, Masao

1976-01-01

Positron lifetime measurements were performed for Cu samples with different densities of lattice defects. The lifetime spectra were successfully resolved into two components with the help of the well established analysis program. Obtained results were quite consistent with those expected from the trapping model. The positron trapping mechanism from free to trapped states and the initial condition of the model were especially checked. Deduced values obtained for tau sub(c) (lifetime of free positrons) and tau sub(t) (lifetime of trapped positrons) were 122+-5 psec and 176+-5 psec, respectively. (auth.)

Spent fuel reprocessing options

International Nuclear Information System (INIS)

2008-08-01

The objective of this publication is to provide an update on the latest developments in nuclear reprocessing technologies in the light of new developments on the global nuclear scene. The background information on spent fuel reprocessing is provided in Section One. Substantial global growth of nuclear electricity generation is expected to occur during this century, in response to environmental issues and to assure the sustainability of the electrical energy supply in both industrial and less-developed countries. This growth carries with it an increasing responsibility to ensure that nuclear fuel cycle technologies are used only for peaceful purposes. In Section Two, an overview of the options for spent fuel reprocessing and their level of development are provided. A number of options exist for the treatment of spent fuel. Some, including those that avoid separation of a pure plutonium stream, are at an advanced level of technological maturity. These could be deployed in the next generation of industrial-scale reprocessing plants, while others (such as dry methods) are at a pilot scale, laboratory scale or conceptual stage of development. In Section Three, research and development in support of advanced reprocessing options is described. Next-generation spent fuel reprocessing plants are likely to be based on aqueous extraction processes that can be designed to a country specific set of spent fuel partitioning criteria for recycling of fissile materials to advanced light water reactors or fast spectrum reactors. The physical design of these plants must incorporate effective means for materials accountancy, safeguards and physical protection. Section four deals with issues and challenges related to spent fuel reprocessing. The spent fuel reprocessing options assessment of economics, proliferation resistance, and environmental impact are discussed. The importance of public acceptance for a reprocessing strategy is discussed. A review of modelling tools to support the

Accelerated lifetime testing methodology for lifetime estimation of Lithium-ion batteries used in augmented wind power plants

DEFF Research Database (Denmark)

Stroe, Daniel Ioan; Swierczynski, Maciej Jozef; Stan, Ana-Irina

2013-01-01

The development of lifetime estimation models for Lithium-ion battery cells, which are working under highly variable mission profiles characteristic for wind power plant applications, requires a lot of expenditures and time resources. Therefore, batteries have to be tested under accelerated...... lifetime ageing conditions. This paper presents a three-stage methodology used for accelerated lifetime testing of Lithium-ion batteries. The results obtained at the end of the accelerated ageing process can be used for the parametrization of a performance-degradation lifetime model. In the proposed...... methodology both calendar and cycling lifetime tests are considered since both components are influencing the lifetime of Lithium-ion batteries. The methodology proposes also a lifetime model verification stage, where Lithium-ion battery cells are tested at normal operating conditions using an application...

Partial Defect Verification of Spent Fuel Assemblies by PDET: Principle and Field Testing in Interim Spent Fuel Storage Facility (CLAB) in Sweden

Energy Technology Data Exchange (ETDEWEB)

Ham, Y.S.; Kerr, P.; Sitaraman, S.; Swan, R. [Global Security Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Rossa, R. [SCK-CEN, Mol (Belgium); Liljenfeldt, H. [SKB in Oskarshamn (Sweden)

2015-07-01

The need for the development of a credible method and instrument for partial defect verification of spent fuel has been emphasized over a few decades in the safeguards communities as the diverted spent fuel pins can be the source of nuclear terrorism or devices. The need is increasingly more important and even urgent as many countries have started to transfer spent fuel to so called 'difficult-to-access' areas such as dry storage casks, reprocessing or geological repositories. Partial defect verification is required by IAEA before spent fuel is placed into 'difficult-to-access' areas. Earlier, Lawrence Livermore National Laboratory (LLNL) has reported the successful development of a new, credible partial defect verification method for pressurized water reactor (PWR) spent fuel assemblies without use of operator data, and further reported the validation experiments using commercial spent fuel assemblies with some missing fuel pins. The method was found to be robust as the method is relatively invariant to the characteristic variations of spent fuel assemblies such as initial fuel enrichment, cooling time, and burn-up. Since then, the PDET system has been designed and prototyped for 17x17 PWR spent fuel assemblies, complete with data acquisition software and acquisition electronics. In this paper, a summary description of the PDET development followed by results of the first successful field testing using the integrated PDET system and actual spent fuel assemblies performed in a commercial spent fuel storage site, known as Central Interim Spent fuel Storage Facility (CLAB) in Sweden will be presented. In addition to partial defect detection initial studies have determined that the tool can be used to verify the operator declared average burnup of the assembly as well as intra-assembly burnup levels. (authors)

Heritability of lifetime ecstasy use.

Science.gov (United States)

Verweij, Karin J H; Treur, Jorien L; Vreeker, Annabel; Brunt, Tibor M; Willemsen, Gonneke; Boomsma, Dorret I; Vink, Jacqueline M

2017-09-01

Ecstasy is a widely used psychoactive drug that users often take because they experience positive effects such as increased euphoria, sociability, elevated mood, and heightened sensations. Ecstasy use is not harmless and several immediate and long term side effects have been identified. Lifetime ecstasy use is likely to be partly influenced by genetic factors, but no twin study has determined the heritability. Here, we apply a classical twin design to a large sample of twins and siblings to estimate the heritability of lifetime ecstasy use. The sample comprised 8500 twins and siblings aged between 18 and 45 years from 5402 families registered at the Netherlands Twin Registry. In 2013-2014 participants filled out a questionnaire including a question whether they had ever used ecstasy. We used the classical twin design to partition the individual differences in liability to ecstasy use into that due to genetic, shared environmental, and residual components. Overall, 10.4% of the sample had used ecstasy during their lifetime, with a somewhat higher prevalence in males than females. Twin modelling indicated that individual differences in liability to lifetime ecstasy use are for 74% due to genetic differences between individuals, whereas shared environmental and residual factors explain a small proportion of its liability (5% and 21%, respectively). Although heritability estimates appeared to be higher for females than males, this difference was not significant. Lifetime ecstasy use is a highly heritable trait, which indicates that some people are genetically more vulnerable to start using ecstasy than others. Copyright © 2017. Published by Elsevier B.V.

Spent fuel receipt and lag storage facility for the spent fuel handling and packaging program

International Nuclear Information System (INIS)

Black, J.E.; King, F.D.

1979-01-01

Savannah River Laboratory (SRL) is participating in the Spent Fuel Handling and Packaging Program for retrievable, near-surface storage of spent light water reactor (LWR) fuel. One of SRL's responsibilities is to provide a technical description of the wet fuel receipt and lag storage part of the Spent Fuel Handling and Packaging (SFHP) facility. This document is the required technical description

Grey Literature Searching for Health Sciences Systematic Reviews: A Prospective Study of Time Spent and Resources Utilized.

Science.gov (United States)

Saleh, Ahlam A; Ratajeski, Melissa A; Bertolet, Marnie

To identify estimates of time taken to search grey literature in support of health sciences systematic reviews and to identify searcher or systematic review characteristics that may impact resource selection or time spent searching. A survey was electronically distributed to searchers embarking on a new systematic review. Characteristics of the searcher and systematic review were collected along with time spent searching and what resources were searched. Time and resources were tabulated and resources were categorized as grey or non-grey. Data was analyzed using Kruskal-Wallis tests. Out of 81 original respondents, 21% followed through with completion of the surveys in their entirety. The median time spent searching all resources was 471 minutes, and of those a median of 85 minutes were spent searching grey literature. The median number of resources used in a systematic review search was four and the median number of grey literature sources searched was two. The amount of time spent searching was influenced by whether the systematic review was grant funded. Additionally, the number of resources searched was impacted by institution type and whether systematic review training was received. This study characterized the amount of time for conducting systematic review searches including searching the grey literature, in addition to the number and types of resources used. This may aid searchers in planning their time, along with providing benchmark information for future studies. This paper contributes by quantifying current grey literature search patterns and associating them with searcher and review characteristics. Further discussion and research into the search approach for grey literature in support of systematic reviews is encouraged.

Research on advanced aqueous reprocessing of spent nuclear fuel: literature study

Energy Technology Data Exchange (ETDEWEB)

Van Hecke, K.; Goethals, P.

2006-07-15

The goal of the partitioning and transmutation strategy is to reduce the radiotoxicity of spent nuclear fuel to the level of natural uranium in a short period of time (about 1000 years) and thus the required containment period of radioactive material in a repository. Furthermore, it aims to reduce the volume of waste requiring deep geological disposal and hence the associated space requirements and costs. Several aqueous as well as pyrochemical separation processes have been developed for the partitioning of the long-lived radionuclides from the remaining of the spent fuel. This report aims to describe and compare advanced aqueous reprocessing methods.

Research on advanced aqueous reprocessing of spent nuclear fuel: literature study

International Nuclear Information System (INIS)

Van Hecke, K.; Goethals, P.

2006-01-01

The goal of the partitioning and transmutation strategy is to reduce the radiotoxicity of spent nuclear fuel to the level of natural uranium in a short period of time (about 1000 years) and thus the required containment period of radioactive material in a repository. Furthermore, it aims to reduce the volume of waste requiring deep geological disposal and hence the associated space requirements and costs. Several aqueous as well as pyrochemical separation processes have been developed for the partitioning of the long-lived radionuclides from the remaining of the spent fuel. This report aims to describe and compare advanced aqueous reprocessing methods.

Lifetime results from heavy quark systems

International Nuclear Information System (INIS)

Papadimitriou, V.

1997-11-01

We present the latest measurements of weakly decaying b-hadrons from experiments at e + e - and p anti p colliders. These measurements include the average lifetime of b-hadrons, lifetimes of the B - , B 0 and B 0 s mesons, the average lifetime of b-baryons and lifetimes of the Λ b and Ξ b baryons

Effects of spent nuclear fuel aging on disposal requirements

International Nuclear Information System (INIS)

McKee, R.W.; Johnson, K.I.; Huber, H.D.; Bierschbach, M.C.

1991-10-01

This paper describes results of a study to analyze the waste management systems effects of extended spent fuel aging on spent fuel disposal requirements. The analysis considers additional spent fuel aging up to a maximum of 50 years relative to the currently planned 2010 repository startup in the United States. As part of the analysis, an equal energy disposition (EED) methodology was developed for determining allowable waste emplacement densities and waste container loading in a geologic repository. Results of this analysis indicate that substantial benefits of spent fuel aging will already have been achieved by a repository startup in 2010 (spent fuel average age will be 28 years). Even so, further significant aging benefits, in terms of reduced emplacement areas and mining requirements and reduced number of waste containers, will continue to accrue for at least another 50 years when the average spent fuel age would be 78 years, if the repository startup is further delayed

Exits in order: How crowding affects particle lifetimes

Energy Technology Data Exchange (ETDEWEB)

Penington, Catherine J.; Simpson, Matthew J. [School of Mathematical Sciences, Queensland University of Technology, Brisbane (Australia); Baker, Ruth E. [Mathematical Institute, University of Oxford, Radcliffe Observatory Quarter, Woodstock Road, Oxford (United Kingdom)

2016-06-28

Diffusive processes are often represented using stochastic random walk frameworks. The amount of time taken for an individual in a random walk to intersect with an absorbing boundary is a fundamental property that is often referred to as the particle lifetime, or the first passage time. The mean lifetime of particles in a random walk model of diffusion is related to the amount of time required for the diffusive process to reach a steady state. Mathematical analysis describing the mean lifetime of particles in a standard model of diffusion without crowding is well known. However, the lifetime of agents in a random walk with crowding has received much less attention. Since many applications of diffusion in biology and biophysics include crowding effects, here we study a discrete model of diffusion that incorporates crowding. Using simulations, we show that crowding has a dramatic effect on agent lifetimes, and we derive an approximate expression for the mean agent lifetime that includes crowding effects. Our expression matches simulation results very well, and highlights the importance of crowding effects that are sometimes overlooked.

Costing of spent nuclear fuel storage

International Nuclear Information System (INIS)

2009-01-01

This report deals with economic analysis and cost estimation, based on exploration of relevant issues, including a survey of analytical tools for assessment and updated information on the market and financial issues associated with spent fuel storage. The development of new storage technologies and changes in some of the circumstances affecting the costs of spent fuel storage are also incorporated. This report aims to provide comprehensive information on spent fuel storage costs to engineers and nuclear professionals as well as other stakeholders in the nuclear industry. This report is meant to provide informative guidance on economic aspects involved in selecting a spent fuel storage system, including basic methods of analysis and cost data for project evaluation and comparison of storage options, together with financial and business aspects associated with spent fuel storage. After the review of technical options for spent fuel storage in Section 2, cost categories and components involved in the lifecycle of a storage facility are identified in Section 3 and factors affecting costs of spent fuel storage are then reviewed in the Section 4. Methods for cost estimation and analysis are introduced in Section 5, and other financial and business aspects associated with spent fuel storage are discussed in Section 6.

Surveillance instrumentation for spent-fuel safeguards

International Nuclear Information System (INIS)

McKenzie, J.M.; Holmes, J.P.; Gillman, L.K.; Schmitz, J.A.; McDaniel, P.J.

1978-01-01

The movement, in a facility, of spent reactor fuel may be tracked using simple instrumentation together with a real time unfolding algorithm. Experimental measurements, from multiple radiation monitors and crane weight and position monitors, were obtained during spent fuel movements at the G.E. Morris Spent-Fuel Storage Facility. These data and a preliminary version of an unfolding algorithm were used to estimate the position of the centroid and the magnitude of the spent fuel radiation source. Spatial location was estimated to +-1.5 m and source magnitude to +-10% of their true values. Application of this surveillance instrumentation to spent-fuel safeguards is discussed

Lifetime Extension Report: Progress on the SAVY-4000 Lifetime Extension Program

International Nuclear Information System (INIS)

Welch, Cynthia F.; Smith, Paul Herrick; Weis, Eric M.; Blair, Michael W.; Stone, Timothy Amos; Veirs, Douglas Kirk; Reeves, Kirk Patrick; Karns, Tristan; Oka, Jude M.; Keller, Jennie; Meincke, Linda Jeanne; Torres, Joseph Angelo; Herman, Matthew Joseph; Weaver, Brian Phillip; Adams, Jillian Cathleen; Trautschold, Olivia Carol

2016-01-01

The 3-year accelerated aging study of the SAVY-4000 O-ring shows very little evidence of significant degradation to samples subjected to aggressive elevated temperature and radiation conditions. Whole container thermal aging studies followed by helium leakage testing and compression set measurements were used to establish an estimate for a failure criterion for O-ring compression set of ?65 %. The whole container aging studies further show that the air flow and efficiency functions of the filter do not degrade significantly after thermal aging. However, the degradation of the water-resistant function leads to water penetration failure after four months at 210°C, but does not cause failure after 10 months at 120°C (130°C is the maximum operating temperature for the PTFE membrane). The thermal aging data for O-ring compression set do not meet the assumptions of standard time-temperature superposition analysis for accelerated aging studies. Instead, the data suggest that multiple degradation mechanisms are operative, with a reversible mechanism operative at low aging temperatures and an irreversible mechanism dominating at high aging temperatures. To distinguish between these mechanisms, we have measured compression set after allowing the sample to physically relax, thereby minimizing the effect of the reversible mechanism. The resulting data were analyzed using two distinct mathematical methods to obtain a lifetime estimate based on chemical degradation alone. Both methods support a lifetime estimate of greater than 150 years at 80°C. Although the role of the reversible mechanism is not fully understood, it is clear that the contribution to the total compression set is small in comparison to that due to the chemical degradation mechanism. To better understand the chemical degradation mechanism, thermally aged O-ring samples have been characterized by Fourier Transform Infrared (FTIR), Electron Paramagnetic Resonance (EPR), Gel Permeation Chromatography (GPC), and

Lifetime Extension Report: Progress on the SAVY-4000 Lifetime Extension Program

Energy Technology Data Exchange (ETDEWEB)

Welch, Cynthia F. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Science and Technology. Engineered Materials; Smith, Paul Herrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Nuclear Process Infrastructure; Weis, Eric M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Science and Technology. Engineered Materials; Blair, Michael W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Science and Technology. Engineered Materials; Stone, Timothy Amos [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Nuclear Process Infrastructure; Veirs, Douglas Kirk [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Manufacturing Engineering and Technology; Reeves, Kirk Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Nuclear Process Infrastructure; Karns, Tristan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Nuclear Process Infrastructure; Oka, Jude M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Nuclear Process Infrastructure; Keller, Jennie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Science and Technology. Engineered Materials; Meincke, Linda Jeanne [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Science and Technology. Engineered Materials; Torres, Joseph Angelo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Science and Technology. Engineered Materials; Herman, Matthew Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Science and Technology. Engineered Materials; Weaver, Brian Phillip [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Computer, Computational, and Statistical Sciences. Statistical Sciences; Adams, Jillian Cathleen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Science and Technology. Engineered Materials; Trautschold, Olivia Carol [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Science and Technology. Engineered Materials

2016-09-20

The 3-year accelerated aging study of the SAVY-4000 O-ring shows very little evidence of significant degradation to samples subjected to aggressive elevated temperature and radiation conditions. Whole container thermal aging studies followed by helium leakage testing and compression set measurements were used to establish an estimate for a failure criterion for O-ring compression set of ≥65 %. The whole container aging studies further show that the air flow and efficiency functions of the filter do not degrade significantly after thermal aging. However, the degradation of the water-resistant function leads to water penetration failure after four months at 210°C, but does not cause failure after 10 months at 120°C (130°C is the maximum operating temperature for the PTFE membrane). The thermal aging data for O-ring compression set do not meet the assumptions of standard time-temperature superposition analysis for accelerated aging studies. Instead, the data suggest that multiple degradation mechanisms are operative, with a reversible mechanism operative at low aging temperatures and an irreversible mechanism dominating at high aging temperatures. To distinguish between these mechanisms, we have measured compression set after allowing the sample to physically relax, thereby minimizing the effect of the reversible mechanism. The resulting data were analyzed using two distinct mathematical methods to obtain a lifetime estimate based on chemical degradation alone. Both methods support a lifetime estimate of greater than 150 years at 80°C. Although the role of the reversible mechanism is not fully understood, it is clear that the contribution to the total compression set is small in comparison to that due to the chemical degradation mechanism. To better understand the chemical degradation mechanism, thermally aged O-ring samples have been characterized by Fourier Transform Infrared (FTIR), Electron Paramagnetic Resonance (EPR), Gel Permeation Chromatography (GPC

A review of the possible effects of hydrogen on lifetime of carbon steel nuclear waste canisters

International Nuclear Information System (INIS)

Turnbull, A.

2009-07-01

In Switzerland, the National Cooperative for the Disposal of Radioactive Waste (Nagra) is responsible for developing an effective method for the safe disposal of vitrified high level waste (HLW) and spent fuel. One of the options for disposal canisters is thick-walled carbon steel. The canisters, which would have a diameter of about 1 m and a length of about 3 m (HLW) or about 5 m (spent fuel), will be embedded in horizontal tunnels and surrounded with bentonite clay. The regulatory requirement for the minimum canister lifetime is 1000 years but demonstration of a minimum lifetime of 10,000 years would be desirable. The pore-water to which the canister will be exposed is of marine origin with about 0.1-0.3 M Cl-. Since hydrogen is generated during the corrosion process, it is necessary to assess the probability of hydrogen assisted cracking modes and to make recommendations to eliminate that probability. To that aim, key reports detailing projections for the local environment and associated corrosion rate of the waste canister have been evaluated with the focus on the implication for the absorbed hydrogen concentration in the steel. Simple calculations of hydrogen diffusion and accumulation in the inner compartment of the sealed canister indicate that a pressure equivalent to that for gas pockets external to the canister (envisaged to be about 10 MPa) may be attained in the proposed exposure time, an important consideration since it is not possible to modify the internal surface of the closure weld. Current ideas on mechanisms of hydrogen assisted cracking are assessed from which it is concluded that the mechanistic understanding and associated models of hydrogen assisted cracking are insufficient to provide a framework for quantitative prediction for this application. The emphasis then was to identify threshold conditions for cracking and to evaluate the likelihood that these may be exceeded over the lifetime of the containment. Based on an analysis of data in the

Genotypic-specific variance in Caenorhabditis elegans lifetime fecundity.

Science.gov (United States)

Diaz, S Anaid; Viney, Mark

2014-06-01

Organisms live in heterogeneous environments, so strategies that maximze fitness in such environments will evolve. Variation in traits is important because it is the raw material on which natural selection acts during evolution. Phenotypic variation is usually thought to be due to genetic variation and/or environmentally induced effects. Therefore, genetically identical individuals in a constant environment should have invariant traits. Clearly, genetically identical individuals do differ phenotypically, usually thought to be due to stochastic processes. It is now becoming clear, especially from studies of unicellular species, that phenotypic variance among genetically identical individuals in a constant environment can be genetically controlled and that therefore, in principle, this can be subject to selection. However, there has been little investigation of these phenomena in multicellular species. Here, we have studied the mean lifetime fecundity (thus a trait likely to be relevant to reproductive success), and variance in lifetime fecundity, in recently-wild isolates of the model nematode Caenorhabditis elegans. We found that these genotypes differed in their variance in lifetime fecundity: some had high variance in fecundity, others very low variance. We find that this variance in lifetime fecundity was negatively related to the mean lifetime fecundity of the lines, and that the variance of the lines was positively correlated between environments. We suggest that the variance in lifetime fecundity may be a bet-hedging strategy used by this species.

Spent fuel: prediction model development

International Nuclear Information System (INIS)

Almassy, M.Y.; Bosi, D.M.; Cantley, D.A.

1979-07-01

The need for spent fuel disposal performance modeling stems from a requirement to assess the risks involved with deep geologic disposal of spent fuel, and to support licensing and public acceptance of spent fuel repositories. Through the balanced program of analysis, diagnostic testing, and disposal demonstration tests, highlighted in this presentation, the goal of defining risks and of quantifying fuel performance during long-term disposal can be attained

A scheme of better utilization of PWR spent fuels

International Nuclear Information System (INIS)

Chung, Bum Jin; Kang, Chang Soon

1991-01-01

The recycle of PWR spent fuels in a CANDU reactor, so called the tandem fuel cycle is investigated in this study. This scheme of utilizing PWR spent fuels will ease the shortage of spent fuel storage capacity as well as will improve the use of uranium resources. The minimum modification the design of present CANDU reactor is seeked in the recycle. Nine different fuel types are considered in this work and are classified into two categories: refabrication and reconfiguration. For refabrication, PWR spent fuels are processed and refabricated into the present 37 rod lattice structure of fuel bundle, and for reconfiguration, meanwhile, spent fuels are simply disassembled and rods are cut to fit into the present grid configuration of fuel bundle without refabrication. For each fuel option, the neutronics calculation of lattice was conducted to evaluate the allowable burn up and distribution. The fuel cycle cost of each option was also computed to assess the economic justification. The results show that most tandem fuel cycle option considered in this study are technically feasible as well as economically viable. (Author)

Positron Annihilation Lifetime Study of Pure and Doped Polyvinyl Chloride with Al2O3

International Nuclear Information System (INIS)

Abdel-Hady, E.E.; Hamdy, F. M. M.; Alaa, H.B.

2005-01-01

Positron annihilation lifetime of pure and doped polyvinyl chloride (PVC) with Al 2 O 3 reflect the effect of concentration as well as temperature on free volume. Therefore, variations of the ortho-positronium (o-Ps) lifetime and its intensity have been correlated with changes in the dielectric properties of the pure and doped PVC. The o-Ps lifetime and its intensity show a linear dependence with a discontinuity at 20 % concentration of Al 2 O 3 . The size and the fractional of the o-Ps hole volume were estimated from the positron annihilation parameters. Therefore, the temperature dependence of the electrical conductivity and the positron annihilation parameters on pure and doped PVC with 20 % Al 2 O 3 were studied in the range from 20 to 140 degree C. The shift of the glass transition temperature to lower temperature for the 20 % Al 2 O 3 doped PVC might explain the increase in the electrical conductivity with the concentration of the additive

Optimization of time and location dependent spent nuclear fuel storage capacity

International Nuclear Information System (INIS)

Macek, V.

1977-01-01

A linear spent fuel storage model is developed to identify cost-effective spent nuclear fuel storage strategies. The purpose of this model is to provide guidelines for the implementation of the optimal time-dependent spent fuel storage capacity expansion in view of the current economic and regulatory environment which has resulted in phase-out of the closed nuclear fuel cycle. Management alternatives of the spent fuel storage backlog, which is created by mismatch between spent fuel generation rate and spent fuel disposition capability, are represented by aggregate decision variables which describe the time dependent on-reactor-site and off-site spent fuel storage capacity additions, and the amount of spent fuel transferred to off-site storage facilities. Principal constraints of the model assure determination of cost optimal spent fuel storage expansion strategies, while spent fuel storage requirements are met at all times. A detailed physical and economic analysis of the essential components of the spent fuel storage problem, which precedes the model development, assures its realism. The effects of technological limitations on the on-site spent fuel storage expansion and timing of reinitiation of the spent fuel reprocessing on optimal spent fuel storage capacity expansion are investigated. The principal results of the study indicate that (a) expansion of storage capacity beyond that of currently planned facilities is necessary, and (b) economics of the post-reactor fuel cycle is extremely sensitive to the timing of reinitiation of spent fuel reprocessing. Postponement of reprocessing beyond mid-1982 may result in net negative economic liability of the back end of the nuclear fuel cycle

An overview on the nuclear spent fuel management in Romania

International Nuclear Information System (INIS)

Radu, M.

2001-01-01

The sources of radioactive waste in Romania are users of radiation and radioactive materials in industry (including nuclear electricity generation), medicine, agriculture and research and also the processing of materials that are naturally radioactive, such as uranium ores. The different types of radioactive waste are classified into four categories of waste: excepted waste, low level waste, medium level waste and high level waste. A spent fuel management sub-programme as a part of the Radioactive Waste Management programme was initiated by the former Romanian Electricity Company (RENEL) in 1992. Within the frame of R and D of the Radioactive Waste and Spent Fuel Management Programme, the topics cover investigations, studies and research to identify the sites and the conceptual designs for a Spent Fuel Interim Storage Facility (SFISF) and also a Spent Fuel Disposal Facility (SFDF). Changes in the organization of the nuclear activities of RENEL, involving both responsibilities and financing aspects, led to interruption of the programme. The programme includes study of the main methods and the existing technologies for the design, operation and safety of an interim storage facility (including transport aspects). It also includes analysis of details on the site selection for this facility and for a spent fuel final disposal facility. The achievement of the spent fuel interim storage facility is proceeding. The results from the studies performed in the last years will permit us to prepare the feasibility study next year and the documentation required by our regulatory body for starting the process to obtain a license for a SFISF at Cernavoda. A second phase is the assessment of a long term strategy to select and adopt a proven disposal technology for spent fuel, corresponding with a selected site. The status of the work performed in the frame of this programme and also the situation of the spent fuel from research reactors are presented. (author)

Spent fuel storage for ISER plant

International Nuclear Information System (INIS)

Nakajima, Takasuke; Kimura, Yuzi

1987-01-01

ISER is an intrinsically safe reactor basing its safety only on physical laws, and uses a steel reactor vessel in order to be economical. For such a new type reactor, it is essentially important to be accepted by the society by showing that the reactor is more profitable than conventional reactors to the public in both technical and economic viewpoint. It is also important that the reactor raises no serious problem in the total fuel cycle. Reprocessing seems one of the major worldwide fuel cycle issues. Spent fuel storage is also one of the key technologies for fuel cycle back end. Various systems for ISER spent fuel storages are examined in the present report. Spent fuel specifications of ISER are similar to those of LWR and therefore, most of LWR spent fuel technologies are basically applicable to ISER spent fuel. Design requirements and examples of storage facilities are also discussed. Dry storage seems to be preferable for the relatively long cooling time spent fuel like ISER's one from economical viewpoint. Vault storage will possibly be the most advantageous for large storage capacity. Another point for discussion is the location and international collaboration for spent fuel storages: ISER expected to be a worldwide energy source and therefore, international spent fuel management seems to be fairly attractive way for an energy recipient country. (Nogami, K.)

Situation and perspective of spent fuel management in Spain

International Nuclear Information System (INIS)

Lopez Garcia, A.

2009-01-01

Between september 2006 and september 2007, the Foundation for Energy Studies carried out the study Radioactive Waste Management: Situation, Analysis and Perspectives. This study focuses specially on spent fuel and high level radioactive waste management. The different aspects covered in this study are as follows: -Description of the different applicable technologies -Analysis and comparison of the different options of spent fuel management, including the strategic and economic aspects. - Situation, strategies and forecasts in the main countries. -Analysis of the situation and alternatives for the spent fuel management in spain. Although the report focuses principally pn the technological and environmental aspects other issues related with the management of these materials were considered, such as the strategic, economic and institutional aspects as well as the social acceptation. In answer to the request of the SNE publication, the article enclosed is a summary of one of the chapters of this study, and more particularly the one dedicated to the situation of spent fuel and high level radioactive waste management in Spain. (Author)

Lifetime of organic photovoltaics

DEFF Research Database (Denmark)

Corazza, Michael; Krebs, Frederik C; Gevorgyan, Suren A.

2015-01-01

tests. Comparison of the indoor and outdoor lifetimes was performed by means of the o-diagram, which constitutes the initial steps towards establishing a method for predicting the lifetime of an organic photovoltaic device under real operational conditions based on a selection of accelerated indoor...

Rock cavern storage of spent fuel

Energy Technology Data Exchange (ETDEWEB)

Cho, Won Jin; Kim, Kyung Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kwon, Sang Ki [Inha University, Incheon (Korea, Republic of)

2015-12-15

The rock cavern storage for spent fuel has been assessed to apply in Korea with reviewing the state of the art of the technologies for surface storage and rock cavern storage of spent fuel. The technical feasibility and economic aspects of the rock cavern storage of spent fuel were also analyzed. A considerable area of flat land isolated from the exterior are needed to meet the requirement for the site of the surface storage facilities. It may, however, not be easy to secure such areas in the mountainous region of Korea. Instead, the spent fuel storage facilities constructed in the rock cavern moderate their demands for the suitable site. As a result, the rock cavern storage is a promising alternative for the storage of spent fuel in the aspect of natural and social environments. The rock cavern storage of spent fuel has several advantages compared with the surface storage, and there is no significant difference on the viewpoint of economy between the two alternatives. In addition, no great technical difficulties are present to apply the rock cavern storage technologies to the storage of domestic spent fuel.

The cost of spent fuel storage

Energy Technology Data Exchange (ETDEWEB)

Ramirez S, J. R.; Palacios H, J. C.; Badillo, V.; Alonso, G., E-mail: ramon.ramirez@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

2011-11-15

Spent fuel is one of the most important issues in the nuclear industry, currently spent fuel management is been cause of great amount of research, investments, constructing repositories or constructing the necessary facilities to reprocess the fuel, and later to recycle the plutonium recovered in thermal reactors. What is the best solution?, or What is the best technology for an specific solution? Many countries have deferred the decision on selecting an option, while others works actively constructing repositories and others implementing the reprocessing facilities to recycle the plutonium obtained from nuclear spent fuel. In Mexico the nuclear power is limited to two reactors BWR type and medium size. So the nuclear spent fuel discharged has been accommodated at reactor's spent fuel pools. Originally these pools have enough capacity to accommodate spent fuel for the 40 years of designed plant operation. However currently, the plants are under a process for extended power up-rate to 20% of original power and also there are plans to extended operational life for 20 more years. Under these conditions there will not be enough room for spent fuel in the pools. (Author)

Transportation of spent nuclear fuels

International Nuclear Information System (INIS)

Meguro, Toshiichi

1976-01-01

The spent nuclear fuel taken out of reactors is cooled in the cooling pool in each power station for a definite time, then transported to a reprocessing plant. At present, there is no reprocessing plant in Japan, therefore the spent nuclear fuel is shipped abroad. In this paper, the experiences and the present situation in Japan are described on the transport of the spent nuclear fuel from light water reactors, centering around the works in Tsuruga Power Station, Japan Atomic Power Co. The spent nuclear fuel in Tsuruga Power Station was first transported in Apr. 1973, and since then, about 36 tons were shipped to Britain by 5 times of transport. The reprocessing plant in Japan is expected to start operation in Apr. 1977, accordingly the spent nuclear fuel used for the trial will be transported in Japan in the latter half of this year. Among the permission and approval required for the transport of spent nuclear fuel, the acquisition of the certificate for transport casks and the approval of land and sea transports are main tasks. The relevant laws are the law concerning the regulations of nuclear raw material, nuclear fuel and reactors and the law concerning the safety of ships. The casks used in Tsuruga Power Station and EXL III type, and the charging of spent nuclear fuel, the decontamination of the casks, the leak test, land transport with a self-running vehicle, loading on board an exclusive carrier and sea transport are briefly explained. The casks and the ship for domestic transport are being prepared. (Kato, I.)

Dry spent fuel storage licensing

International Nuclear Information System (INIS)

Sturz, F.C.

1995-01-01

In the US, at-reactor-site dry spent fuel storage in independent spent fuel storage installations (ISFSI) has become the principal option for utilities needing storage capacity outside of the reactor spent fuel pools. Delays in the geologic repository operational date at or beyond 2010, and the increasing uncertainty of the US Department of Energy's (DOE) being able to site and license a Monitored Retrievable Storage (MRS) facility by 1998 make at-reactor-site dry storage of spent nuclear fuel increasingly desirable to utilities and DOE to meet the need for additional spent fuel storage capacity until disposal, in a repository, is available. The past year has been another busy year for dry spent fuel storage licensing. The licensing staff has been reviewing 7 applications and 12 amendment requests, as well as participating in inspection-related activities. The authors have licensed, on a site-specific basis, a variety of dry technologies (cask, module, and vault). By using certified designs, site-specific licensing is no longer required. Another new cask has been certified. They have received one new application for cask certification and two amendments to a certified cask design. As they stand on the brink of receiving multiple applications from DOE for the MPC, they are preparing to meet the needs of this national program. With the range of technical and licensing options available to utilities, the authors believe that utilities can meet their need for additional spent fuel storage capacity for essentially all reactor sites through the next decade

Case histories of West Valley spent fuel shipments: Final report

Energy Technology Data Exchange (ETDEWEB)

1987-01-01

In 1983, NRC/FC initiated a study on institutional issues related to spent fuel shipments originating at the former spent fuel processing facility in West Valley, New York. FC staff viewed the shipment campaigns as a one-time opportunity to document the institutional issues that may arise with a substantial increase in spent fuel shipping activity. NRC subsequently contracted with the Aerospace Corporation for the West Valley Study. This report contains a detailed description of the events which took place prior to and during the spent fuel shipments. The report also contains a discussion of the shipment issues that arose, and presents general findings. Most of the institutional issues discussed in the report do not fall under NRC's transportation authority. The case histories provide a reference to agencies and other institutions that may be involved in future spent fuel shipping campaigns. 130 refs., 7 figs., 19 tabs.

Arrival condition of spent fuel after storage, handling, and transportation

International Nuclear Information System (INIS)

Bailey, W.J.; Pankaskie, P.J.; Langstaff, D.C.; Gilbert, E.R.; Rising, K.H.; Schreiber, R.E.

1982-11-01

This report presents the results of a study conducted to determine the probable arrival condition of spent light-water reactor (LWR) fuel after handling and interim storage in spent fuel storage pools and subsequent handling and accident-free transport operations under normal or slightly abnormal conditions. The objective of this study was to provide information on the expected condition of spent LWR fuel upon arrival at interim storage or fuel reprocessing facilities or at disposal facilities if the fuel is declared a waste. Results of a literature survey and data evaluation effort are discussed. Preliminary threshold limits for storing, handling, and transporting unconsolidated spent LWR fuel are presented. The difficulty in trying to anticipate the amount of corrosion products (crud) that may be on spent fuel in future shipments is also discussed, and potential areas for future work are listed. 95 references, 3 figures, 17 tables

Case histories of West Valley spent fuel shipments: Final report

International Nuclear Information System (INIS)

1987-01-01

In 1983, NRC/FC initiated a study on institutional issues related to spent fuel shipments originating at the former spent fuel processing facility in West Valley, New York. FC staff viewed the shipment campaigns as a one-time opportunity to document the institutional issues that may arise with a substantial increase in spent fuel shipping activity. NRC subsequently contracted with the Aerospace Corporation for the West Valley Study. This report contains a detailed description of the events which took place prior to and during the spent fuel shipments. The report also contains a discussion of the shipment issues that arose, and presents general findings. Most of the institutional issues discussed in the report do not fall under NRC's transportation authority. The case histories provide a reference to agencies and other institutions that may be involved in future spent fuel shipping campaigns. 130 refs., 7 figs., 19 tabs

Development of spent fuel remote handling technology

International Nuclear Information System (INIS)

Yoon, Ji Sup; Park, B. S.; Park, Y. S.; Oh, S. C.; Kim, S. H.; Cho, M. W.; Hong, D. H.

1997-12-01

Since the nation's policy on spent fuel management is not finalized, the technical items commonly required for safe management and recycling of spent fuel - remote technologies of transportation, inspection, maintenance, and disassembly of spent fuel - are selected and pursued. In this regards, the following R and D activities are carried out : collision free transportation of spent fuel assembly, mechanical disassembly of spent nuclear fuel and graphical simulation of fuel handling / disassembly process. (author). 36 refs., 16 tabs., 77 figs

Adolescent Depression and Time Spent with Parents and Siblings

Science.gov (United States)

Desha, Laura N.; Nicholson, Jan M.; Ziviani, Jenny M.

2011-01-01

This study examines adolescent depressive symptoms and the quantity and quality of time spent by adolescents with their parents and siblings. We use measures of the quality of relationships with parents and siblings as proxy indicators for the quality of time spent with these social partners. The study emphasizes the salience of parent…

West Valley facility spent fuel handling, storage, and shipping experience

International Nuclear Information System (INIS)

Bailey, W.J.

1990-11-01

The result of a study on handling and shipping experience with spent fuel are described in this report. The study was performed by Pacific Northwest Laboratory (PNL) and was jointly sponsored by the US Department of Energy (DOE) and the Electric Power Research Institute (EPRI). The purpose of the study was to document the experience with handling and shipping of relatively old light-water reactor (LWR) fuel that has been in pool storage at the West Valley facility, which is at the Western New York Nuclear Service Center at West Valley, New York and operated by DOE. A subject of particular interest in the study was the behavior of corrosion product deposits (i.e., crud) deposits on spent LWR fuel after long-term pool storage; some evidence of crud loosening has been observed with fuel that was stored for extended periods at the West Valley facility and at other sites. Conclusions associated with the experience to date with old spent fuel that has been stored at the West Valley facility are presented. The conclusions are drawn from these subject areas: a general overview of the West Valley experience, handling of spent fuel, storing of spent fuel, rod consolidation, shipping of spent fuel, crud loosening, and visual inspection. A list of recommendations is provided. 61 refs., 4 figs., 5 tabs

Moisture dependence of positron lifetime in Kevlar-49

Science.gov (United States)

Singh, Jag J.; Holt, William H.; Mock, Willis, Jr.

1984-01-01

Because of filamentary character of Kevlar-49 aramid fibers, there is some concern about the moisture uptake and its effect on plastic composites reinforced with Kevlar-49 fibers. As part of continuing studies of positron lifetime in polymers, we have measured positron lifetime spectra in Kevlar-49 fibers as a function of their moisture content. The long lifetime component intensities are rather low, being only of the order of 2-3 percent. The measured values of long component lifetimes at various moisture levels in the specimens are as follows: 2072 +/- 173 ps (dry); 2013 +/- 193 ps (20.7 percent saturation); 1665 +/- 85 ps (25.7 percent saturation); 1745 +/- 257 ps (32.1 percent saturation); and 1772 +/- 217 ps (100 percent saturation). It is apparent that the long component lifetime at first decreases and then increases as the specimen moisture content increases. These results have been compared with those inferred from Epon-815 and Epon-815/K-49 composite data.

The Lifetime Prediction of LED Drivers and Lamps

NARCIS (Netherlands)

Sun, B.

2017-01-01

Light-Emitting Diodes (LEDs) have become a very promising alternative lighting source with the main advantages of a longer lifetime and a higher efficiency than traditional ones. However, the LED lamp’s lifetime is compromised by its driver’s reliability. Although extensive studies have been made on

Spent-fuel storage: a private sector option

International Nuclear Information System (INIS)

Thomas, J.A.; Ross, S.R.

1983-01-01

The investigation was performed to delineate the legal and financial considerations for establishing private sector support for the planning and development of an independent spent-fuel storage facility (ISFSF). The preferred institutional structure was found to be one in which a not-for-profit corporation contracts with a limited partnership to handle the spent fuel. The limited partnership acquires the necessary land and constructs the ISFSF facility and then leases the facility to the not-for-profit corporation, which acquires spent-fuel rods from the utilities. The DOE must agree to purchase the spent-fuel rods at the expiration of term and warrant continued operation of the facility if policy changes at the federal level force the removal of the rods prior to completion of the contracted storage cycle. The DOE planning base estimate of spent-fuel storage requirements indicates a market potential adequate to support 10,000 MTU or more of spent-fuel storage prior to the time a government repository is available to accept spent fuel around the turn of the century. The estimated construction cost of a 5000-MTU water basin facility is $552 million. The total capital requirements to finance such a facility are estimated to be $695 million, based on an assumed capital structure of 70 percent debt and 30 percent equity. The estimated total levelized cost of storage, including operating costs, for the assumed 17-year life of the facility is $223 per kilogram of uranium. This is equivalent to a slightly less than one mill per kilowatt-hour increase in nuclear fuel costs at the nuclear power station that was the source of the spent fuel. In conclusion, within the context of the new Nuclear Waste Policy Act of 1982, the study points to both the need for and the advantages of private sector support for one or more ISFSFs and establishes a workable mechanism for the recovery of the costs of owning and operating such facilities. 3 figures, 4 tables

Accelerated Lifetime Testing Methodology for Lifetime Estimation of Lithium-ion Batteries used in Augmented Wind Power Plants

DEFF Research Database (Denmark)

Stroe, Daniel Ioan; Swierczynski, Maciej Jozef; Stan, Ana-Irina

2014-01-01

The development of lifetime estimation models for Lithium-ion battery cells, which are working under highly variable mission profiles characteristic for wind power plant applications, requires a lot of expenditures and time resources. Therefore, batteries have to be tested under accelerated...... lifetime ageing conditions. This paper presents a three-stage methodology used for accelerated lifetime testing of Lithium ion batteries. The results obtained at the end of the accelerated ageing process were used for the parametrization of a performance-degradation lifetime model, which is able to predict...... both the capacity fade and the power capability decrease of the selected Lithium-ion battery cells. In the proposed methodology both calendar and cycling lifetime tests were considered since both components are influencing the lifetime of Lithium-ion batteries. Furthermore, the proposed methodology...

Development of spent fuel remote handling technology

Energy Technology Data Exchange (ETDEWEB)

Yoon, Ji Sup; Park, B S; Park, Y S; Oh, S C; Kim, S H; Cho, M W; Hong, D H

1997-12-01

Since the nation`s policy on spent fuel management is not finalized, the technical items commonly required for safe management and recycling of spent fuel - remote technologies of transportation, inspection, maintenance, and disassembly of spent fuel - are selected and pursued. In this regards, the following R and D activities are carried out : collision free transportation of spent fuel assembly, mechanical disassembly of spent nuclear fuel and graphical simulation of fuel handling / disassembly process. (author). 36 refs., 16 tabs., 77 figs

The Lifetime of a beautiful and charming meson: B_c lifetime measured using the D0 detector

Energy Technology Data Exchange (ETDEWEB)

Welty-Rieger, Leah Christine [Indiana Univ., Bloomington, IN (United States)

2008-09-01

Using approximately 1.3 fb^-1 of data collected by the D0 detector between 2002 and 2006, the lifetime of the B_c^± meson is studied in the B_c^± → J/Ψμ^± + X final state. Using an unbinned likelihood simultaneous fit to J/Ψ + μ invariant mass and lifetime distributions, a signal of 810 ± 80(stat.) candidates is estimated and a lifetime measurement made of: τ(B_c^±) = 0.448_-0.036^+0.038(stat) ± 0.032(sys) ps.

German Approach to Spent Fuel Management

International Nuclear Information System (INIS)

Jussofie, A.; Graf, R.; Filbert, W.

2010-01-01

The management of spent fuel was based on two powerful columns until 30 June 2005, i. e. reprocessing and direct disposal. After this date any delivery of spent fuel to reprocessing plants was prohibited so that the direct disposal of unreprocessed spent fuel is the only available option in Germany today. The main steps of the current concept are: (i) Intermediate storage of spent fuel, which is the only step in practice. After the first cooling period in spent fuel storage pools it continues into cask-receiving dry storage facilities. Identification of casks, 'freezing' of inventories in terms of continuity of knowledge, monitoring the access to spent fuel, verifying nuclear material movements in terms of cask transfers and ensurance against diversion of nuclear material belong to the fundamental safeguards goals which have been achieved in the intermediate storage facilities by containment and surveillance techniques in unattended mode. (ii) Conditioning of spent fuel assemblies by separating the fuel rods from structural elements. Since the pilot conditioning facility in Gorleben has not yet come into operation, the underlying safeguards approach which focuses on safeguarding the key measurement points - the spent fuel related way in and out of the facility - has not been applied yet. (iii) Disposal in deep geological formations, but no decision has been made so far neither regarding the location of a geological repository nor regarding the safeguards approach for the disposal concept of spent fuel. The situation was complicated by a moratorium which suspended the underground exploration of the Gorleben salt dome as potential geological repository for spent fuel. The moratorium expires in October 2010. Nevertheless, considerable progress has been made in the development of disposal concepts. According to the basic, so-called POLLUX (registered) -concept spent fuel assemblies are to be conditioned after dry storage and reloaded into the POLLUX (registered) -cask

Investigation of novel spent fuel verification system for safeguard application

Energy Technology Data Exchange (ETDEWEB)

Lee, Haneol; Yim, Man-Sung [KAIST, Daejeon (Korea, Republic of)

2016-10-15

Radioactive waste, especially spent fuel, is generated from the operation of nuclear power plants. The final stage of radioactive waste management is disposal which isolates radioactive waste from the accessible environment and allows it to decay. The safety, security, and safeguard of a spent fuel repository have to be evaluated before its operation. Many researchers have evaluated the safety of a repository. These researchers calculated dose to public after the repository is closed depending on their scenario. Because most spent fuel repositories are non-retrievable, research on security or safeguards of spent fuel repositories have to be performed. Design based security or safeguard have to be developed for future repository designs. This study summarizes the requirements of future spent fuel repositories especially safeguards, and suggests a novel system which meets the safeguard requirements. Applying safeguards to a spent fuel repository is becoming increasingly important. The future requirements for a spent fuel repository are suggested by several expert groups, such as ASTOR in IAEA. The requirements emphasizes surveillance and verification. The surveillance and verification of spent fuel is currently accomplished by using the Cerenkov radiation detector while spent fuel is being stored in a fuel pool. This research investigated an advanced spent fuel verification system using a system which converts spent fuel radiation into electricity. The system generates electricity while it is conveyed from a transportation cask to a disposal cask. The electricity conversion system was verified in a lab scale experiment using an 8.51GBq Cs-137 gamma source.

Investigation of novel spent fuel verification system for safeguard application

International Nuclear Information System (INIS)

Lee, Haneol; Yim, Man-Sung

2016-01-01

Radioactive waste, especially spent fuel, is generated from the operation of nuclear power plants. The final stage of radioactive waste management is disposal which isolates radioactive waste from the accessible environment and allows it to decay. The safety, security, and safeguard of a spent fuel repository have to be evaluated before its operation. Many researchers have evaluated the safety of a repository. These researchers calculated dose to public after the repository is closed depending on their scenario. Because most spent fuel repositories are non-retrievable, research on security or safeguards of spent fuel repositories have to be performed. Design based security or safeguard have to be developed for future repository designs. This study summarizes the requirements of future spent fuel repositories especially safeguards, and suggests a novel system which meets the safeguard requirements. Applying safeguards to a spent fuel repository is becoming increasingly important. The future requirements for a spent fuel repository are suggested by several expert groups, such as ASTOR in IAEA. The requirements emphasizes surveillance and verification. The surveillance and verification of spent fuel is currently accomplished by using the Cerenkov radiation detector while spent fuel is being stored in a fuel pool. This research investigated an advanced spent fuel verification system using a system which converts spent fuel radiation into electricity. The system generates electricity while it is conveyed from a transportation cask to a disposal cask. The electricity conversion system was verified in a lab scale experiment using an 8.51GBq Cs-137 gamma source

Necessity and opportunity of building a mobile facility for conditioning the spent ionic resins

International Nuclear Information System (INIS)

Barariu, Gheorghe

2002-01-01

The ionic resins utilized in nuclear industry for purification of different working fluids become contaminated by important amounts of radionuclides incorporated in their structure. Thus, these resins become intermediate-level radioactive wastes, containing radioisotopes of rather long lifetimes, and so their conditioning is required to ensure binding and isolation of the radionuclides over a period long enough, until their decay. Binding the radionuclides in stable matrices and their isolation by means of engineered barriers ensures protection of environment against contamination. In the frame of Radioactive Waste Management Program related to Cernavoda NPP, optimal technologies for processing the radioactive waste generated during the NPP operation were developed and also a site for final disposal of the low and intermediate level waste was selected. The last one is a modern, ground repository with multiple engineered barriers based on the natural properties of the host geological formation. The final disposal concept implies building a conditioning facility to ensure: a super-compacting stage of the already compacted wastes; cementing the uncompactable wastes; cementing spent filters; cementing the pellets resulted from the super-compacting stage and drums with conditioned wastes in concrete modules; cementing the organic wastes; cementing the spent ionic resins by means of a mobile facility. The spent ionic resins removed from the technologic purification systems of the station are discharged by means of demineralized water and transferred, corresponding to source, to one of the 3 storage 200 m 3 basins from the basement of the CANDU 6 NPP servicing building. To avoid the danger of spent resins being cemented at basin's bottom the basins should be emptied at every 10-15 years. To comply with IAEA requirements concerning the radioactive waste final disposal, a procedure for establishing the quantitative concentration of solidification agents and additives

A study on the properties of blended regenerated spent catalyst and cement sandcrete blocks

International Nuclear Information System (INIS)

Amissah, Emmanuel Kofi

2016-07-01

Sandcrete is widely used as building material. Its properties greatly depend on the properties and proportions of its constituents. The main binder material to produce sandcrete is the Portland cement. The uncertainty about future availability of commonly used Portland materials concomitantly with the environmental problems such as greenhouse gases emissions and high cost of clinker consumption are highlighting the need of identifying other materials for the construction industry, which will aid in minimizing the clinker consumption and reduce the greenhouse gas emissions and cost in the production of cement. The purpose of this study is to examine the properties of sandcrete blocks produced with blended Regenerated Spent Catalyst and cement. In this work, two different series of sandcrete mixtures in which cement was partially replaced with Regenerated Spent Catalyst(RSC) within the range of 5% to 20% (by mass) with an increment of 5%. 100% cement sandcrete was also prepared as reference sandcrete. The physical properties studied were compressive strength, water absorption and setting time. Chemical property studied was chloride content. Comparison of data between the control and that of cement with additives were made. The results obtained in this study clearly indicated that substituting Portland cement up to 20wt. % RSC gave sandcrete strengths higher than the 32.5N/mm 2 , which corresponds to that of Portland cement. The replacement of Portland cement with 10 wt. % of RSC gave the highest strength of 34.0 N/mm 2 . Thus, Regenerated Spent Catalyst may be utilized as effective mineral additive for designing durable sandcrete structures. The optimum amount of RSC recommended to be added as an additive to the Portland cement is 10%. (au)

Energy Savings Lifetimes and Persistence

Energy Technology Data Exchange (ETDEWEB)

Hoffman, Ian M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schiller, Steven R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Todd, Annika [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Billingsley, Megan A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Goldman, Charles A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schwartz, Lisa C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2016-02-01

This technical brief explains the concepts of energy savings lifetimes and savings persistence and discusses how program administrators use these factors to calculate savings for efficiency measures, programs and portfolios. Savings lifetime is the length of time that one or more energy efficiency measures or activities save energy, and savings persistence is the change in savings throughout the functional life of a given efficiency measure or activity. Savings lifetimes are essential for assessing the lifecycle benefits and cost effectiveness of efficiency activities and for forecasting loads in resource planning. The brief also provides estimates of savings lifetimes derived from a national collection of costs and savings for electric efficiency programs and portfolios.

Positron Lifetime Study of the Transition from Glassy to Normal Liquid State for Two Phenyl Ethers

DEFF Research Database (Denmark)

Pethrick, R. A.; Jacobsen, F. M.; Mogensen, O. E.

1980-01-01

Positron lifetime measurements are reported as a function of temperature for bis[m-(m-phenoxyphenoxy)phenyl] ether and m-phenoxyphenyl-m-(m-phenoxyphenoxy)phenyl ether. The decay curves were analysed in terms of three lifetime components; two short lifetimes of typically 200 and 500 ps associated...

Spent fuels transportation coming from Australia

International Nuclear Information System (INIS)

2002-01-01

Maritime transportation of spent fuels from Australia to France fits into the contract between COGEMA and ANSTO, signed in 1999. This document proposes nine information cards in this domain: HIFAR a key tool of the nuclear, scientific and technological australian program; a presentation of the ANSTO Australian Nuclear Science and Technology Organization; the HIFAR spent fuel management problem; the COGEMA expertise in favor of the research reactor spent fuel; the spent fuel reprocessing at La Hague; the transports management; the transport safety (2 cards); the regulatory framework of the transports. (A.L.B.)

Safety analysis of spent fuel packaging

International Nuclear Information System (INIS)

Akamatsu, Hiroshi; Taniuchi, Hiroaki; Tai, Hideto

1987-01-01

Many types of spent fuel packagings have been manufactured and been used for transport of spent fuels discharged from nuclear power plant. These spent fuel packagings need to be assesed thoroughly about safety transportation because spent fuels loaded into the packaging have high radioactivity and generation of heat. This paper explains the outline of safety analysis of a packaging, Safety analysis is performed for structural, thermal, containment, shielding and criticality factors, and MARC-CDC, TRUMP, ORIGEN, QAD, ANISN, KENO, etc computer codes are used for such analysis. (author)

SIRTF thermal design modifications to increase lifetime

Science.gov (United States)

Petrick, S. W.

1993-01-01

An effort was made to increase the predicted lifetime of the SIRTF dewar by lowering the exterior shell temperature, increasing the radiated energy from the vapor cooled shields and reconfiguring the vapor cooled shields. The lifetime increases can be used to increase the scientific return from the mission and as a trade-off against mass and cost. This paper describes the configurations studied, the steady state thermal model used, the analytical methods and the results of the analysis. Much of the heat input to the outside dewar shell is radiative heat transfer from the solar panel. To lower the shell temperature, radiative cooled shields were placed between the solar panel and the dewar shell and between the bus and the dewar shell. Analysis showed that placing a radiator on the outer vapor cooled shield had a significant effect on lifetime. Lengthening the distance between the outer shell and the point where the vapor cooled shields are attached to the support straps also improved lifetime.

The psychosocial consequences of spent fuel disposal

International Nuclear Information System (INIS)

Paavola, J.; Eraenen, L.

1999-03-01

In this report the potential psychosocial consequences of spent fuel disposal to inhabitants of a community are assessed on the basis of earlier research. In studying the situation, different interpretations and meanings given to nuclear power are considered. First, spent fuel disposal is studied as fear-arousing and consequently stressful situation. Psychosomatic effects of stress and coping strategies used by an individual are presented. Stress as a collective phenomenon and coping mechanisms available for a community are also assessed. Stress reactions caused by natural disasters and technological disasters are compared. Consequences of nuclear power plant accidents are reviewed, e.g. research done on the accident at Three Mile Island power plant. Reasons for the disorganising effect on a community caused by a technological disaster are compared to the altruistic community often seen after natural disasters. The potential reactions that a spent fuel disposal plant can arouse in inhabitants are evaluated. Both short-term and long-term reactions are evaluated as well as reactions under normal functioning, after an incident and as a consequence of an accident. Finally an evaluation of how the decision-making system and citizens' opportunity to influence the decision-making affect the experience of threat is expressed. As a conclusion we see that spent fuel disposal can arouse fear and stress in people. However, the level of the stress is probably low. The stress is at strongest at the time of the starting of the spent fuel disposal plant. With time people get used to the presence of the plant and the threat experienced gets smaller. (orig.)

Spent nuclear fuel disposal liability insurance

International Nuclear Information System (INIS)

Martin, D.W.

1984-01-01

This thesis examines the social efficiency of nuclear power when the risks of accidental releases of spent fuel radionuclides from a spent fuel disposal facility are considered. The analysis consists of two major parts. First, a theoretical economic model of the use of nuclear power including the risks associated with releases of radionuclides from a disposal facility is developed. Second, the costs of nuclear power, including the risks associated with a radionuclide release, are empirically compared to the costs of fossil fuel-fired generation of electricity. Under the provisions of the Nuclear Waste Policy Act of 1982, the federally owned and operated spent nuclear fuel disposal facility is not required to maintain a reserve fund to cover damages from an accidental radionuclide release. Thus, the risks of a harmful radionuclide release are not included in the spent nuclear fuel disposal fee charged to the electric utilities. Since the electric utilities do not pay the full, social costs of spent fuel disposal, they use nuclear fuel in excess of the social optimum. An insurance mechanism is proposed to internalize the risks associated with spent fueled disposal. Under this proposal, the Federal government is required to insure the disposal facility against any liabilities arising from accidental releases of spent fuel radionuclides

Global Spent Fuel Logistics Systems Study (GSFLS). Volume 3. GSFLS technical and financial analysis. Interim report

International Nuclear Information System (INIS)

1978-01-01

This report is a part of the interim report documentation for the Global Spent Fuel Logistics System (GSFLS) study. The technical and financial considerations underlying a global spent fuel logistics systems have been studied and are reported herein. The Pacific Basin is used as a model throughout this report; however the stated methodology and, in many cases, considerations and conclusions are applicable to other global regions. Spent fuel discharge profiles for Pacific Basin Countries were used to determine the technical systems requirements for alternative concepts. Functional analyses and flows were generated to define both system design requirements and logistics parameters. A technology review was made to ascertain the state-of-the-art of relevant GSFLS technical systems. Modular GSFLS facility designs were developed using the information generated from the functional analysis and technology review. The modular facility designs were used as a basis for siting and cost estimates for various GSFLS alternatives. Various GSFLS concepts were analyzed from a financial and economic perspective in order to provide total concepts costs and ascertain financial and economic sensitivities to key GSFLS variations. Results of the study include quantification of GSFLS facility and hardware requirements; drawings of relevant GSFLS facility designs; system cost estimates; financial reports - including user service charges; and comparative analyses of various GSFLS alternatives

Global Spent Fuel Logistics Systems Study (GSFLS). Volume 3A. GSFLS technical analysis (appendix). Interim report

International Nuclear Information System (INIS)

1978-01-01

This report is a part of the interim report documentation for the Global Spent Fuel Logistics System (GSFLS) study. The technical and financial considerations underlying a global spent fuel logistics systems have been studied and are reported. The Pacific Basin is used as a model throughout this report; however the stated methodology and, in many cases, considerations and conclusions are applicable to other global regions. Spent fuel discharge profiles for Pacific Basin Countries were used to determine the technical systems requirements for alternative concepts. Functional analyses and flows were generated to define both system design requirements and logistics parameters. A technology review was made to ascertain the state-of-the-art of relevant GSFLS technical systems. Modular GSFLS facility designs were developed using the information generated from the functional analysis and technology review. The modular facility designs were used as a basis for siting and cost estimates for various GSFLS alternatives. Various GSFLS concepts were analyzed from a financial and economic perspective in order to provide total concepts costs and ascertain financial and economic sensitivities to key GSFLS variations. Results of the study include quantification of GSFLS facility and hardware requirements; drawings of relevant GSFLS facility designs; system cost estimates; financial reports - including user service charges; and comparative analyses of various GSFLS alternatives

Global Spent Fuel Logistics Systems Study (GSFLS). Volume 3A. GSFLS technical analysis (appendix). Interim report

Energy Technology Data Exchange (ETDEWEB)

Kriger, A.

1978-01-31

This report is a part of the interim report documentation for the Global Spent Fuel Logistics System (GSFLS) study. The technical and financial considerations underlying a global spent fuel logistics systems have been studied and are reported. The Pacific Basin is used as a model throughout this report; however the stated methodology and, in many cases, considerations and conclusions are applicable to other global regions. Spent fuel discharge profiles for Pacific Basin Countries were used to determine the technical systems requirements for alternative concepts. Functional analyses and flows were generated to define both system design requirements and logistics parameters. A technology review was made to ascertain the state-of-the-art of relevant GSFLS technical systems. Modular GSFLS facility designs were developed using the information generated from the functional analysis and technology review. The modular facility designs were used as a basis for siting and cost estimates for various GSFLS alternatives. Various GSFLS concepts were analyzed from a financial and economic perspective in order to provide total concepts costs and ascertain financial and economic sensitivities to key GSFLS variations. Results of the study include quantification of GSFLS facility and hardware requirements; drawings of relevant GSFLS facility designs; system cost estimates; financial reports - including user service charges; and comparative analyses of various GSFLS alternatives.

Intermodal transportation of spent fuel

International Nuclear Information System (INIS)

Elder, H.K.

1983-09-01

Concepts for transportation of spent fuel in rail casks from nuclear power plant sites with no rail service are under consideration by the US Department of Energy in the Commercial Spent Fuel Management program at the Pacific Northwest Laboratory. This report identifies and evaluates three alternative systems for intermodal transfer of spent fuel: heavy-haul truck to rail, barge to rail, and barge to heavy-haul truck. This report concludes that, with some modifications and provisions for new equipment, existing rail and marine systems can provide a transportation base for the intermodal transfer of spent fuel to federal interim storage facilities. Some needed land transportation support and loading and unloading equipment does not currently exist. There are insufficient shipping casks available at this time, but the industrial capability to meet projected needs appears adequate

Near surface spent fuel storage: environmental issues

International Nuclear Information System (INIS)

Nelson, I.C.; Shipler, D.B.; McKee, R.W.; Glenn, R.D.

1979-01-01

Interim storage of spent fuel appears inevitable because of the lack of reprocessing plants and spent fuel repositories. This paper examines the environmental issues potentially associated with management of spent fuel before disposal or reprocessing in a reference scenario. The radiological impacts of spent fuel storage are limited to low-level releases of noble gases and iodine. Water needed for water basin storage of spent fuel and transportation accidents are considered; the need to minimize the distance travelled is pointed out. Resource commitments for construction of the storage facilities are analyzed

Acceptance of spent fuel of varying characteristics

International Nuclear Information System (INIS)

Short, S.M.

1990-03-01

This paper is a preliminary overview of a study with the primary objective of establishing a set of acceptance selection criteria and corresponding spent fuel characteristics to be incorporated as a component of requirements for the Federal Waste Management System (FWMS). A number of alternative acceptance allocations and selection rules were analyzed to determine the operational sensitivity of each element of the FWMS to the resultant spent fuel characteristics. Preliminary recommendations of the study include three different sets of selection rules to be included in the FWMS design basis. 2 refs., 4 figs., 4 tabs

China's spent nuclear fuel management: Current practices and future strategies

International Nuclear Information System (INIS)

Zhou Yun

2011-01-01

Although China's nuclear power industry is relatively young and the management of its spent nuclear fuel is not yet a concern, China's commitment to nuclear energy and its rapid pace of development require detailed analyses of its future spent fuel management policies. The purpose of this study is to provide an overview of China's fuel cycle program and its reprocessing policy, and to suggest strategies for managing its future fuel cycle program. The study is broken into four sections. The first reviews China's current nuclear fuel cycle program and facilities. The second discusses China's current spent fuel management methods and the storage capability of China's 13 operational nuclear power plants. The third estimates China's total accumulated spent fuel, its required spent fuel storage from present day until 2035, when China expects its first commercialized fast neutron reactors to be operational, and its likely demand for uranium resources. The fourth examines several spent fuel management scenarios for the present period up until 2035; the financial cost and proliferation risk of each scenario is evaluated. The study concludes that China can and should maintain a reprocessing operation to meet its R and D activities before its fast reactor program is further developed. - Highlights: → This study provides an overview of China's fuel cycle program and its reprocessing policy.→ This study suggests strategies for managing its future fuel cycle program.→ China will experience no pressure to lessen the burden of spent fuel storage in the next 30 years.→ China should maintain sufficient reprocessing operations to meet its demands for R and D activities.→ China should actively invest on R and D activities of both fuel cycling and fast reactor programs.

Study of lifetimes of low-lying levels in {sup 53}Mn

Energy Technology Data Exchange (ETDEWEB)

Singh, K.P.; Oswal, Mumtaz; Behera, B.R.; Kumar, Ashok; Singh, Gulzar [Panjab University, Cyclotron Laboratory, Department of Physics, Centre of Advance Study in Physics, Chandigarh (India)

2015-05-15

The properties of low-lying states of {sup 53}Mn were investigated via the {sup 53}Cr(p, n γ){sup 53}Mn reaction using 4.3 MeV proton beam energy. The lifetimes of the levels at 1289.5, 1440.8, 1620.0 and 2273.8 keV excitation energies were measured using the Doppler Shift Attenuation Method (DSAM). The reduced transition probabilities B(M1) and B(E2) were extracted using the measured values of lifetimes for these levels and the mixing ratios from the literature. These values are compared with already known experimental values as well as the shell model calculations using an effective interaction. (orig.)

Monitoring instrumentation spent fuel management program. Final report

International Nuclear Information System (INIS)

1979-01-01

Preliminary monitoring system methodologies are identified as an input to the risk assessment of spent fuel management. Conceptual approaches to instrumentation for surveillance of canister position and orientation, vault deformation, spent fuel dissolution, temperature, and health physics conditions are presented. In future studies, the resolution, reliability, and uncertainty associated with these monitoring system methodologies will be evaluated

Spent Fuel Management Newsletter. No. 1

International Nuclear Information System (INIS)

1990-03-01

This Newsletter has been prepared in accordance with the recommendations of the International Regular Advisory Group on Spent Fuel Management and the Agency's programme (GC XXXII/837, Table 76, item 14). The main purpose of the Newsletter is to provide Member States with new information about the state-of-the-art in one of the most important parts of the nuclear fuel cycle - Spent Fuel Management. The contents of this publication consists of two parts: (1) IAEA Secretariat contribution -work and programme of the Nuclear Materials and Fuel Cycle Technology Section of the Division of Nuclear Fuel Cycle and Waste Management, recent and planned meetings and publications, Technical Co-operation projects, Co-ordinated Research programmes, etc. (2) Country reports - national programmes on spent fuel management: current and planned storage and reprocessing capacities, spent fuel arisings, safety, transportation, storage, treatment of spent fuel, some aspects of uranium and plutonium recycling, etc. The IAEA expects to publish the Newsletter once every two years between the publications of the Regular Advisory Group on Spent Fuel Management. Figs and tabs

Spent Nuclear Fuel project, project management plan

International Nuclear Information System (INIS)

Fuquay, B.J.

1995-01-01

The Hanford Spent Nuclear Fuel Project has been established to safely store spent nuclear fuel at the Hanford Site. This Project Management Plan sets forth the management basis for the Spent Nuclear Fuel Project. The plan applies to all fabrication and construction projects, operation of the Spent Nuclear Fuel Project facilities, and necessary engineering and management functions within the scope of the project

Electrically induced metastability in SI-GaAs studied by positron lifetime spectroscopy

International Nuclear Information System (INIS)

Luo, Y.L.; Beling, C.D.; Fung, S.; Ling, C.C.; Lui, M.K.; Mui, W.K.

2001-01-01

Recently, a room temperature electrically induced metastability in semi-insulating (SI)-GaAs has been reported in which the normally high resistance state of SI-GaAs converts into a low resistance state when breakdown electric fields are applied to the metal/Si-GaAs/metal system. The low resistance state persists when the electric field is lowered below the breakdown bias and as such may thus be considered as metastable state of the material. To clarify whether the high field breakdown has its origins in some atomic configurational change induced through high energy electron collisions we have employed positron lifetime spectroscopy. Lifetime spectra that have been taken at the same bias in both the high current and low current phases show that the positron lifetime in the metastable state has no change within the experimental error from that of the normal state, thus suggesting that the metastability is most likely of purely electronic origin. (orig.)

Review of charm and beauty lifetimes

International Nuclear Information System (INIS)

Cheung, Harry W. K.

1999-01-01

A review of the latest experimental results on charm and beauty particle lifetimes is presented together with a brief summary of measurement methods used for beauty particle lifetime measurements. There have been significant updates to the D s + /D 0 , B + /B d 0 and Λ b 0 /B d 0 lifetime ratios which have some theoretical implications. However more precise measurements are still needed before one can make conclusive statements about the theory used to calculate the particle lifetimes

The TRIple PLunger for EXotic beams TRIPLEX for excited-state lifetime measurement studies on rare isotopes

Energy Technology Data Exchange (ETDEWEB)

Iwasaki, H., E-mail: iwasaki@nscl.msu.edu [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States); Dewald, A.; Braunroth, T.; Fransen, C. [Institut für Kernphysik der Universität zu Köln, D-50937 Cologne (Germany); Smalley, D. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Lemasson, A. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); GANIL, CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5 (France); Morse, C.; Whitmore, K.; Loelius, C. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States)

2016-01-11

A new device, the TRIple PLunger for EXotic beams (TRIPLEX), has been developed for lifetime measurement studies with rare isotope beams. This plunger device holds up to three metal foils in the beam path and facilitates the recoil distance Doppler-shift technique to measure lifetimes of nuclear excited states in the range of 1 ps to 1 ns. The unique design allows independent movement of the target and the second degrader with respect to a fixed first degrader in between, enabling advanced experimental approaches, such as the differential recoil distance method and the double recoil distance method. The design and control of the device are presented in this paper, together with simulated performances of the new applications. As an example of actual experiments, results from the lifetime measurement of the neutron-rich {sup 17}C isotope performed at the National Superconducting Cyclotron Laboratory are shown.

Cask operation and maintenance for spent fuel storage

Energy Technology Data Exchange (ETDEWEB)

Lee, J.S. [International Atomic Energy Agency, Vienna (Austria)

2004-07-01

Interim storage is an essential platform for any option to be chosen later as an endpoint for spent fuel management. In view of such a circumstance, the most imminent service required for the spent fuel management worldwide is to provide adequate storage for the future spent fuel inventory arising either from the continued operation of nuclear power plants or from the removal of spent fuel in preparation for plant decommissioning. While the bulk of the global inventory of spent fuel are still stored in AR pools, dry storage has become a prominent alternative especially for newly built AFR facilities, with more than 17,000 t HM already stored in dry storage facilities worldwide. Storage in cask under inert conditions has become the preferred option, given the advantages including passive cooling features and modular mode of capacity increase. In terms of economics, dry storage is particularly propitious for long-term storage in that operational costs are minimized by the passive cooling features. The trend toward dry storage, especially in cask type, is likely to continue with an implication that and the supply will closely follow the increasing demand for storage by incremental additions of casks to the effect of minimizing cost penalty of the idle capacities typical of pool facilities. A variety of storage systems have been developed to meet specific requirements of different reactor fuels and a large number of designs based on these generic technologies are now available for the spent fuel containers (horizontal, vertical etc) and storage facilities. Multi-purpose technologies (i.e. a single technology for storage, transportation and disposal) have also been studied. Recent concern on security measures for protection of spent fuel has prompted a consideration on the possibility of placing storage facility underground. The future evolution of requirements and technologies will bring important impacts on cask operation and maintenance for spent fuel storage.

Cask operation and maintenance for spent fuel storage

International Nuclear Information System (INIS)

Lee, J.S.

2004-01-01

Interim storage is an essential platform for any option to be chosen later as an endpoint for spent fuel management. In view of such a circumstance, the most imminent service required for the spent fuel management worldwide is to provide adequate storage for the future spent fuel inventory arising either from the continued operation of nuclear power plants or from the removal of spent fuel in preparation for plant decommissioning. While the bulk of the global inventory of spent fuel are still stored in AR pools, dry storage has become a prominent alternative especially for newly built AFR facilities, with more than 17,000 t HM already stored in dry storage facilities worldwide. Storage in cask under inert conditions has become the preferred option, given the advantages including passive cooling features and modular mode of capacity increase. In terms of economics, dry storage is particularly propitious for long-term storage in that operational costs are minimized by the passive cooling features. The trend toward dry storage, especially in cask type, is likely to continue with an implication that and the supply will closely follow the increasing demand for storage by incremental additions of casks to the effect of minimizing cost penalty of the idle capacities typical of pool facilities. A variety of storage systems have been developed to meet specific requirements of different reactor fuels and a large number of designs based on these generic technologies are now available for the spent fuel containers (horizontal, vertical etc) and storage facilities. Multi-purpose technologies (i.e. a single technology for storage, transportation and disposal) have also been studied. Recent concern on security measures for protection of spent fuel has prompted a consideration on the possibility of placing storage facility underground. The future evolution of requirements and technologies will bring important impacts on cask operation and maintenance for spent fuel storage

Fact sheet on spent fuel management

International Nuclear Information System (INIS)

2006-01-01

The IAEA gives high priority to safe and effective spent fuel management. As an example of continuing efforts, the 2003 International Conference on Storage of Spent Fuel from Power Reactors gathered 125 participants from 35 member states to exchange information on this important subject. With its large number of Member States, the IAEA is well-positioned to gather and share information useful in addressing Member State priorities. IAEA activities on this topic include plans to produce technical documents as resources for a range of priority topics: spent fuel performance assessment and research, burnup credit applications, cask maintenance, cask loading optimization, long term storage requirements including records maintenance, economics, spent fuel treatment, remote technology, and influence of fuel design on spent fuel storage. In addition to broader topics, the IAEA supports coordinated research projects and technical cooperation projects focused on specific needs. The proceedings of the 2003 IAEA conference on storage of spent fuel from power reactors has been ranked in the top twenty most accessed IAEA publications. These proceedings are available for free downloads at http://www-pub.iaea.org/MTCD/publications/PubDetails.asp?pubId=6924]. The IAEA organized and held a 2004 meeting focused on long term spent fuel storage provisions in Central and Eastern Europe, using technical cooperation funds to support participation by these Member States. Over ninety percent of the participants in this meeting rated its value as good or excellent, with participants noting that the IAEA is having a positive effect in stimulating communication, cooperation, and information dissemination on this important topic. The IAEA was advised in 2004 that results from a recent coordinated research project (IAEA-TECDOC-1343) were used by one Member State to justify higher clad temperatures for spent fuel in dry storage, leading to more efficient storage and reduced costs. Long term

Lifetime measurements using the Jefferson Lad Load-Lock Electron Gun

International Nuclear Information System (INIS)

J. Grames; P. Adderley; M. Baylac; J. Brittian; D. Charles; J. Clark; J. Hansknecht; M. Poelker; M. Stutzman; K. Surles-Law

2000-01-01

Lifetime measurements of bulk GaAs using a 100 kV load-lock electron gun and beam line were made. Initial tests used anodized samples to study lifetime under various conditions (gun vacuum, laser spot location, activated area). Subsequent tests used a mechanical mask to limit the active area and included improved monitoring of the gun chamber and beam line vacuum pressure. Results of these measurements support claims made at past workshops, namely photocathode lifetime improves when gun vacuum is enhanced and when electron emission from the edge of the photocathode is eliminated. The dependence upon laser spot location is less certain. Tests studying lifetime at higher beam intensity (I ∼ 8 mA) have begun

Time Spent Outdoors, Depressive Symptoms, and Variation by Race and Ethnicity.

Science.gov (United States)

Beyer, Kirsten M M; Szabo, Aniko; Nattinger, Ann B

2016-09-01

Numerous studies have explored neighborhood environmental correlates of mental illnesses, presuming that the time individuals spend in their environment can confer benefit or harm based on environmental characteristics. However, few population-based studies have directly examined the relationship between time spent outdoors and mental health, and little work has been done to explore how experiences differ by race and ethnicity. Though some have proposed "doses of outdoor time" to improve health, the absence of information about the benefits conferred by particular "doses," and expected baseline levels of outdoor time, are needed to inform the development of recommendations and interventions. This study examined the relationship between time spent outdoors and depression among a population-based sample of American adults, characterized current levels of time spent outdoors by race and ethnicity, and examined how the relationship between time spent outdoors and depression varies by race and ethnicity. Descriptive statistics and survey regression models were used to examine data from the National Health and Nutrition Examination Survey for 2009-2012. Findings provide evidence that time spent outdoors is associated with fewer depressive symptoms, but this benefit may not be equally distributed by race and ethnicity. Descriptive analyses also reveal differences in time spent outdoors among different racial and ethnic groups. Study findings support the notion that increasing time spent outdoors may result in mental health benefits. However, this study questions whether that benefit is experienced equally among different groups, particularly given differences in occupational experiences and environmental characteristics of neighborhoods. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Temperature dependence study of positronium formation in high density polyethylene by positron annihilation lifetime spectroscopy

International Nuclear Information System (INIS)

Nahid, F.; Beling, C.D.; Fung, S.

2007-01-01

Positron annihilation lifetime spectroscopy has been used to study the formation of positronium in high density polyethylene as a function of temperature over the range 30 K-350 K. It is observed that the thermal history of the sample, while having no influence on the positronium lifetime, has a strong effect on the formation of positronium. A hysteresis is seen in the positronium formation probability in cooling and heating cycles. This is explained on a two channel formation model, the first channel being through ''blob'' formation and the second through the pick-up of shallow trapped electrons. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Experimental study of the lifetime and phase transition in neutron-rich Zr 98 ,100 ,102

Science.gov (United States)

Ansari, S.; Régis, J.-M.; Jolie, J.; Saed-Samii, N.; Warr, N.; Korten, W.; Zielińska, M.; Salsac, M.-D.; Blanc, A.; Jentschel, M.; Köster, U.; Mutti, P.; Soldner, T.; Simpson, G. S.; Drouet, F.; Vancraeyenest, A.; de France, G.; Clément, E.; Stezowski, O.; Ur, C. A.; Urban, W.; Regan, P. H.; Podolyák, Zs.; Larijani, C.; Townsley, C.; Carroll, R.; Wilson, E.; Mach, H.; Fraile, L. M.; Paziy, V.; Olaizola, B.; Vedia, V.; Bruce, A. M.; Roberts, O. J.; Smith, J. F.; Scheck, M.; Kröll, T.; Hartig, A.-L.; Ignatov, A.; Ilieva, S.; Lalkovski, S.; Mǎrginean, N.; Otsuka, T.; Shimizu, N.; Togashi, T.; Tsunoda, Y.

2017-11-01

Rapid shape changes are observed for neutron-rich nuclei with A around 100. In particular, a sudden onset of ground-state deformation is observed in the Zr and Sr isotopic chains at N = 60: Low-lying states in N ≤58 nuclei are nearly spherical, while those with N ≥60 have a rotational character. Nuclear lifetimes as short as a few picoseconds can be measured using fast-timing techniques with LaBr3(Ce) scintillators, yielding a key ingredient in the systematic study of the shape evolution in this region. We used neutron-induced fission of 241Pu and 235U to study lifetimes of excited states in fission fragments in the A ˜100 region with the EXILL-FATIMA array located at the PF1B cold neutron beam line at the Institut Laue-Langevin. In particular, we applied the generalized centroid difference method to deduce lifetimes of low-lying states for the nuclei 98Zr (N = 58), 100Zr, and 102Zr (N ≥60 ). The results are discussed in the context of the presumed phase transition in the Zr chain by comparing the experimental transition strengths with the theoretical calculations using the interacting boson model and the Monte Carlo shell model.

Actin cytoskeleton-dependent Rab GTPase-regulated angiotensin type I receptor lysosomal degradation studied by fluorescence lifetime imaging microscopy

Science.gov (United States)

Li, Hewang; Yu, Peiying; Sun, Yuansheng; Felder, Robin A.; Periasamy, Ammasi; Jose, Pedro A.

2010-09-01

The dynamic regulation of the cellular trafficking of human angiotensin (Ang) type 1 receptor (AT1R) is not well understood. Therefore, we investigated the cellular trafficking of AT1R-enhanced green fluorescent protein (EGFP) (AT1R-EGFP) heterologously expressed in HEK293 cells by determining the change in donor lifetime (AT1R-EGFP) in the presence or absence of acceptor(s) using fluorescence lifetime imaging-fluorescence resonance energy transfer (FRET) microscopy. The average lifetime of AT1R-EGFP in our donor-alone samples was ~2.33 ns. The basal state lifetime was shortened slightly in the presence of Rab5 (2.01+/-0.10 ns) or Rab7 (2.11+/-0.11 ns) labeled with Alexa 555, as the acceptor fluorophore. A 5-min Ang II treatment markedly shortened the lifetime of AT1R-EGFP in the presence of Rab5-Alexa 555 (1.78+/-0.31 ns) but was affected minimally in the presence of Rab7-Alexa 555 (2.09+/-0.37 ns). A 30-min Ang II treatment further decreased the AT1R-EGFP lifetime in the presence of both Rab5- and Rab7-Alexa 555. Latrunculin A but not nocodazole pretreatment blocked the ability of Ang II to shorten the AT1R-EGFP lifetime. The occurrence of FRET between AT1R-EGFP (donor) and LAMP1-Alexa 555 (acceptor) with Ang II stimulation was impaired by photobleaching the acceptor. These studies demonstrate that Ang II-induced AT1R lysosomal degradation through its association with LAMP1 is regulated by Rab5/7 via mechanisms that are dependent on intact actin cytoskeletons.

Time variation of fluorescence lifetime in enhanced cyan fluorescence protein

International Nuclear Information System (INIS)

Lee, Soonhyouk; Kim, Soo Yong; Park, Kyoungsook; Jeong, Jinyoung; Chung, Bong Hyun; Kim, Sok Won

2010-01-01

The lifetime variations of enhanced cyan fluorescence protein (ECFP) in relatively short integration time bins were studied via time-correlated single photon counting (TCSPC) measurement. We observed that minimum photon counts are necessary for the lifetime estimation to achieve a certain range of variance. The conditions to decrease the variance of lifetime were investigated and the channel width of the measurement of TCSPC data was found to be another important factor for the variance of lifetime. Though the lifetime of ECFP is best fit by a double exponential, a mono exponential fit for the same integration time is more stable. The results may be useful in the analysis of photophysical dynamics for ensemble molecules in short measurement time windows.

Fluorescence Lifetime Imaging in Stargardt Disease: Potential Marker for Disease Progression

OpenAIRE

Dysli Chantal; Wolf Sebastian; Hatz Katja; Zinkernagel Martin

2016-01-01

PURPOSE The purpose of this study was to describe autofluorescence lifetime characteristics in Stargardt disease (STGD) using fluorescence lifetime imaging ophthalmoscopy (FLIO) and to investigate potential prognostic markers for disease activity and progression. METHODS Fluorescence lifetime data of 16 patients with STGD (mean age, 40 years; range, 22-56 years) and 15 age-matched controls were acquired using a fluorescence lifetime imaging ophthalmoscope based on a Heidelberg Eng...

Insight into carrier lifetime impact on band-modulation devices

Science.gov (United States)

Parihar, Mukta Singh; Lee, Kyung Hwa; Park, Hyung Jin; Lacord, Joris; Martinie, Sébastien; Barbé, Jean-Charles; Xu, Yue; El Dirani, Hassan; Taur, Yuan; Cristoloveanu, Sorin; Bawedin, Maryline

2018-05-01

A systematic study to model and characterize the band-modulation Z2-FET device is developed bringing light to the relevance of the carrier lifetime influence. This work provides guidelines to optimize the Z2-FETs for sharp switching, ESD protection, and 1T-DRAM applications. Lower carrier lifetime in the Z2-FET helps in attaining the sharp switch. We provide new insights into the correlation between generation/recombination, diffusion, electrostatic barriers and carrier lifetime.

Modulated electron-multiplied fluorescence lifetime imaging microscope: all-solid-state camera for fluorescence lifetime imaging.

Science.gov (United States)

Zhao, Qiaole; Schelen, Ben; Schouten, Raymond; van den Oever, Rein; Leenen, René; van Kuijk, Harry; Peters, Inge; Polderdijk, Frank; Bosiers, Jan; Raspe, Marcel; Jalink, Kees; Geert Sander de Jong, Jan; van Geest, Bert; Stoop, Karel; Young, Ian Ted

2012-12-01

We have built an all-solid-state camera that is directly modulated at the pixel level for frequency-domain fluorescence lifetime imaging microscopy (FLIM) measurements. This novel camera eliminates the need for an image intensifier through the use of an application-specific charge coupled device design in a frequency-domain FLIM system. The first stage of evaluation for the camera has been carried out. Camera characteristics such as noise distribution, dark current influence, camera gain, sampling density, sensitivity, linearity of photometric response, and optical transfer function have been studied through experiments. We are able to do lifetime measurement using our modulated, electron-multiplied fluorescence lifetime imaging microscope (MEM-FLIM) camera for various objects, e.g., fluorescein solution, fixed green fluorescent protein (GFP) cells, and GFP-actin stained live cells. A detailed comparison of a conventional microchannel plate (MCP)-based FLIM system and the MEM-FLIM system is presented. The MEM-FLIM camera shows higher resolution and a better image quality. The MEM-FLIM camera provides a new opportunity for performing frequency-domain FLIM.

Lifetime measurement in neutron-rich A ∝ 100 nuclei

Energy Technology Data Exchange (ETDEWEB)

Ansari, Saba; Jolie, Jan; Regis, Jean-Marc; Saed-Samii, Nima; Warr, Nigel [Institute for Nuclear Physics, University of Cologne, Cologne (Germany); Collaboration: EXILL-FATIMA-Collaboration

2016-07-01

Rapid shape changes are observed in the region of neutron rich nuclei with a mass around A=100. Precise lifetime measurements are a key ingredient in the systematic study of the evolution of nuclear deformation and the degree of collectivity in this region. Nuclear lifetimes of excited states can be obtained using the fast-timing technique with LaBr{sub 3}(Ce)-scintillators. We used neutron induced fission of {sup 241}Pu in order to study lifetimes of excited states of fission fragments in the A∝100 region. The EXILL-FATIMA array located at the PF1B cold neutron beam line at the Institut Laue-Langevin comprises of 8 BGO-shielded EXOGAM clover detectors and 16 very fast LaBr{sub 3}(Ce)-scintillator detectors, which were installed around the fission target. We have studied the lifetimes of low lying states for the nuclei {sup 98}Zr, {sup 100}Zr and {sup 102}Zr by applying the generalized centroid difference method. In this contribution we report on the used fast-timing setup and present preliminary results for the studied isotopes.

Some factors to consider in handling and storing spent fuel

International Nuclear Information System (INIS)

Bailey, W.J.

1985-11-01

This report includes information from various studies performed under the Wet Storage Task of the Behavior of Spent Fuel in Storage Project of the Commercial Spent Fuel Management (CSFM) Program at Pacific Northwest Laboratory. Wet storage experience has been summarized earlier in several other reports. This report summarizes pertinent items noted during FY 1985 concerning recent developments in the handling and storage of spent fuel and associated considerations. The subjects discussed include recent publications, findings, and developments associated with: (1) storage of water reactor spent fuel in water pools, (2) extended-burnup fuel, (3) fuel assembly reconstitution and reinsertion, (4) rod consolidation, (5) variations in the US Nuclear Regulatory Commission's definition of failed fuel, (6) detection of failed fuel rods, and (7) extended integrity of spent fuel. A list of pertinent publications is included

Transmutation of DUPIC spent fuel in the hyper system

International Nuclear Information System (INIS)

Kim, Y.H.; Song, T.Y.

2005-01-01

In this paper, the transmutation of TRUs of the DUPIC (Direct Use of Spent PWR Fuel in CANDU) spent fuel has been studied with the HYPER system, which is an LBE-cooled ADS. The DUPIC concept is a synergistic combination of PWRs and CANDUs, in which PWR spent fuels are directly re-utilized in CANDU reactors after a very simple re-fabrication process. In the DUPIC-HYPER fuel cycle, TRUs are recovered by using a pyro-technology and they are incinerated in a metallic fuel form of U-TRU-Zr. The objective of this study is to investigate the TRU transmutation potential of the HYPER core for the DUPIC-HYPER fuel cycle. All the previously-developed HYPER core design concepts were retained except that fuel is composed of TRU from the DUPIC spent fuel. In order to reduce the burnup reactivity swing, a B 4 C burnable absorber is used. The HYPER core characteristics have been analyzed with the REBUS-3/DIF3D code system. (authors)

Lifetimes of some b-flavored hadrons

International Nuclear Information System (INIS)

Stone, S.

2014-06-01

Recent measurements of lifetimes of some b-flavored hadrons are presented and interpreted in the context of theoretical models, especially the Heavy Quark Expansion. Decay widths and decay width differences in the B s 0 - B-bar s 0 system are discussed from the studies of decays into the final states J/ψK + K - , J/ψπ + π - , D s + D s - , K + K - and D s ± π ± . Lifetime measurements of the baryons Λ b 0 , Ξ b - , Ξ b 0 , and Ω b - are also shown. (author)

Positron lifetime in vanadium oxide bronzes

International Nuclear Information System (INIS)

Dryzek, J.; Dryzek, E.

2003-01-01

The positron lifetime (PL) and Doppler broadening (DB) of annihilation line measurements have been performed in vanadium oxide bronzes M x V 2 O 5 . The dependence of these annihilation characteristics on the kind and concentration of the metal M donor has been observed. In the PL spectrum only one lifetime component has been detected in all studied bronzes. The results indicate the positron localization in the structural tunnels present in the crystalline lattice of the vanadium oxide bronzes. (copyright 2003 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Accelerated lifetime test of vibration isolator made of Metal Rubber material

Science.gov (United States)

Ao, Hongrui; Ma, Yong; Wang, Xianbiao; Chen, Jianye; Jiang, Hongyuan

2017-01-01

The Metal Rubber material (MR) is a kind of material with nonlinear damping characteristics for its application in the field of aerospace, petrochemical industry and so on. The study on the lifetime of MR material is impendent to its application in engineering. Based on the dynamic characteristic of MR, the accelerated lifetime experiments of vibration isolators made of MR working under random vibration load were conducted. The effects of structural parameters of MR components on the lifetime of isolators were studied and modelled with the fitting curves of degradation data. The lifetime prediction methods were proposed based on the models.

The Susquehanna plant lifetime excellence program

International Nuclear Information System (INIS)

McNamara, R.W.

1988-01-01

This paper discusses how the Susquehanna plant lifetime excellence program (SPLEX) blends many of the objectives of a new managing for excellence program with plant life extension objectives to achieve excellence in the lifetime operation and availability of the two-unit Susquehanna steam electric station. Investments in lifetime excellence improvements will provide near-term, as well as plant life extension, benefits. A high-quality lifetime experience record, together with extensive, periodic technical assessments and cost-benefit analyses, will provide conclusive justification for future extensions of the unit operating licenses

Management and storage of spent nuclear fuel at research and test reactors. Proceedings of an advisory group meeting

International Nuclear Information System (INIS)

1996-08-01

Irradiated fuel from research and test reactors has been stored at various facilities for several decades. As these facilities age and approach or exceed their original design lifetimes, there is mounting concern about closure of the fuel cycle and about the integrity of ageing fuels from the materials point of view as well as some concern about the loss of self-protection of the fuels as their activity decays. It is clear that an international effort is necessary to give these problems sufficient exposure and to ensure that work continues on appropriate solutions. The future of nuclear research, with its many benefits to mankind, is in jeopardy in some countries, especially countries without nuclear power programmes, because effective solutions for extended interim storage and final disposition of spent research reactor fuels are not yet available. An advisory Group meeting was convened in Vienna to consider a Database on the Management and Storage of Spent Nuclear Fuel from Research and Test Reactors. Sixteen experts from sixteen different countries participated in the Advisory Group meeting and presented country reports, which together represent an overview of the technologies used in spent fuel management and storage at research and test reactors world-wide. The sixteen country reports together with the database summary are presented in this publication. Refs, figs, tabs

Measurement of Charm Meson Lifetimes

International Nuclear Information System (INIS)

Bonvicini, G.; Cinabro, D.; Greene, R.; Perera, L.P.; Zhou, G.J.; Chan, S.; Eigen, G.; Lipeles, E.; Schmidtler, M.; Shapiro, A.; Sun, W.M.; Urheim, J.; Weinstein, A.J.; Wuerthwein, F.; Jaffe, D.E.; Masek, G.; Paar, H.P.; Potter, E.M.; Prell, S.; Sharma, V.; Asner, D.M.; Eppich, A.; Gronberg, J.; Hill, T.S.; Korte, C.M.; Lange, D.J.; Morrison, R.J.; Nelson, H.N.; Nelson, T.K.; Roberts, D.; Tajima, H.; Behrens, B.H.; Ford, W.T.; Gritsan, A.; Krieg, H.; Roy, J.; Smith, J.G.; Alexander, J.P.; Baker, R.; Bebek, C.; Berger, B.E.; Berkelman, K.; Boisvert, V.; Cassel, D.G.; Crowcroft, D.S.; Dickson, M.; Dombrowski, S. von; Drell, P.S.; Dumas, D.J.; Ecklund, K.M.; Ehrlich, R.; Foland, A.D.; Gaidarev, P.; Gibbons, L.; Gittelman, B.; Gray, S.W.; Hartill, D.L.; Heltsley, B.K.; Henderson, S.; Hopman, P.I.; Katayama, N.; Kreinick, D.L.; Lee, T.; Liu, Y.; Meyer, T.O.; Mistry, N.B.; Ng, C.R.; Nordberg, E.; Ogg, M.; Patterson, J.R.; Peterson, D.; Riley, D.; Soffer, A.; Thayer, J.G.; Thies, P.G.; Valant-Spaight, B.; Warburton, A.; Ward, C.; Athanas, M.; Avery, P.; Jones, C.D.; Lohner, M.; Prescott, C.; Rubiera, A.I.; Yelton, J.; Zheng, J.; Brandenburg, G.; Briere, R.A.; Ershov, A.; Gao, Y.S.; Kim, D.Y.; Wilson, R.; Browder, T.E.; Li, Y.; Rodriguez, J.L.; Yamamoto, H.; Bergfeld, T.; Eisenstein, B.I.; Ernst, J.; Gladding, G.E.; Gollin, G.D

1999-01-01

We report measurements of the D 0 , D + , and D + s meson lifetimes using 3.7 fb -1 of e + e - annihilation data collected near the Υ(4S) resonance with the CLEO detector. The measured lifetimes of the D 0 , D + , and D + s mesons are 408.5±4.1 +3.5 -3.4 fs , 1033.6±22.1 +9.9 -12.7 fs , and 486.3±15.0 +4.9 -5.1 fs . The precision of these lifetimes are comparable to those of the best previous measurements, and the systematic errors are very different. In a single experiment we find that the ratio of the D + s and D 0 lifetimes is 1.19±0.04 . copyright 1999 The American Physical Society

Study of mechanical and physicochemical properties of cementated spent ion-exchange-resins

International Nuclear Information System (INIS)

Patek, P.

1981-09-01

As first part of a study on the possibilities, to immobilize spent ion exchange resins, for final disposal, the dependence of compressive strength from the composition of cement - resin mixtures was detected. Powdered resins, bead resins and ashes from the incinerator plant and several cement brands were examinated. As result an area was defined in the three-phase diagram of cement, resins and water, in which the following leach tests will be performed. (author)

Predicting sample lifetimes in creep fracture of heterogeneous materials

Science.gov (United States)

Koivisto, Juha; Ovaska, Markus; Miksic, Amandine; Laurson, Lasse; Alava, Mikko J.

2016-08-01

Materials flow—under creep or constant loads—and, finally, fail. The prediction of sample lifetimes is an important and highly challenging problem because of the inherently heterogeneous nature of most materials that results in large sample-to-sample lifetime fluctuations, even under the same conditions. We study creep deformation of paper sheets as one heterogeneous material and thus show how to predict lifetimes of individual samples by exploiting the "universal" features in the sample-inherent creep curves, particularly the passage to an accelerating creep rate. Using simulations of a viscoelastic fiber bundle model, we illustrate how deformation localization controls the shape of the creep curve and thus the degree of lifetime predictability.

Spent fuel dry storage in Hungary

International Nuclear Information System (INIS)

Buday, G.; Szabo, B.; Oerdoegh, M.; Takats, F.

1999-01-01

Paks Nuclear Power Plant is the only NPP in Hungary. It has four WWER-440 type reactor units. Since 1989, approximately 40-50% of the total annual electricity generation of the country has been supplied by this plant. The fresh fuel is imported from Russia. Most of the spent fuel assemblies have been shipped back to Russia. Difficulties with spent fuel transportation to Russia have begun in 1992. Since that time, some of the shipments were delayed, some of them were completely cancelled, thus creating a backlog of spent fuel filling all storage positions of the plant. To provide assurance of the continued operation, Paks NPPs management decided to implement an independent spent fuel storage facility and chose GEC-Althom's MVDS design. The construction of the facility started in February 1995 and the first spent fuel assembly was placed in the store in September 1997. The paper gives an overview of the situation, describing the conditions leading to the construction of the dry storage facility at Paks and its implementation. Finally, some information is given about the new Public Agency for Radioactive Waste Management established this year and responsible for managing the issues related to spent fuel management. (author)

Overview of spent fuel management and problems

International Nuclear Information System (INIS)

Ritchie, I.G.; Ernst, P.C.

1998-01-01

Results compiled in the research reactor spent fuel database are used to assess the status of research reactor spent fuel worldwide. Fuel assemblies, their types, enrichment, origin of enrichment and geological distribution among the industrialized and developed countries of the world are discussed. Fuel management practices in wet and dry storage facilities and the concerns of reactor operators about long-term storage of their spent fuel are presented and some of the activities carried out by the International Atomic Energy Agency to address the issues associated with research reactor spent fuel are outlined. Some projections of spent fuel inventories to the year 2006 are presented and discussed. (author)

Modular dry storage of spent fuel

International Nuclear Information System (INIS)

Baxter, J.W.

1982-01-01

Long term uncertainties in US spent fuel reprocessing and storage policies and programs are forcing the electric utilities to consider means of storing spent fuel at the reactor site in increasing quantitities and for protracted periods. Utilities have taken initial steps in increasing storage capacity. Existing wet storage pools have in many cases been reracked to optimize their capacity for storing spent fuel assemblies

CO2 absorption of perovskites as seen by positron lifetime spectroscopy

International Nuclear Information System (INIS)

Suevegh, K.; Nomura, K.; Juhasz, G.; Homonnay, Z.; Vertes, A.

2000-01-01

The CO 2 absorption of several ABO 3 type perovskites was studied by positron lifetime spectroscopy. The longer positron lifetime was associated with positrons trapped by A site vacancies. The evaluated positron lifetime data indicated the relative stability of the crystal structure of Sr(Co 0.5 Fe 0.5 )O 3-δ against Ca doping at low Ca concentrations. Oxygen desorption and CO 2 absorption/desorption could also be followed by positron lifetime spectroscopy. It was shown that the concentration of oxygen vacancies has a large effect on positron lifetime data through the electron density of A site vacancies.

Spent fuel element storage facility

International Nuclear Information System (INIS)

Ukaji, Hideo; Yamashita, Rikuo.

1981-01-01

Purpose: To always keep water level of a spent fuel cask pit equal with water level of spent fuel storage pool by means of syphon principle. Constitution: The pool water of a spent fuel storage pool is airtightly communicated through a pipe with the pool water of a spent fuel cask, and a gate is provided between the pool and the cask. Since cask is conveyed into the cask pit as the gate close while conveying, the pool water level is raised an amount corresponding to the volume of the cask, and water flow through scattering pipe and the communication pipe to the storage pool. When the fuel is conveyed out of the cask, the water level is lowered in the amount corresponding to the volume in the cask pit, and the water in the pool flow through the communication pipe to the cask pit. (Sekiya, K.)

Angular distributions as lifetime probes

Energy Technology Data Exchange (ETDEWEB)

Dror, Jeff Asaf; Grossman, Yuval [Department of Physics, LEPP, Cornell University,Ithaca, NY 14853 (United States)

2014-06-27

If new TeV scale particles are discovered, it will be important to determine their width. There is, however, a problematic region, where the width is too small to be determined directly, and too large to generate a secondary vertex. For a collection of colored, spin polarized particles, hadronization depolarizes the particles prior to their decay. The amount of depolarization can be used to probe the lifetime in the problematic region. In this paper we apply this method to a realistic scenario of a top-like particle that can be produced at the LHC. We study how depolarization affects the angular distributions of the decay products and derive an equation for the distributions that is sensitive to the lifetime.

Autofluorescence Lifetimes in Geographic Atrophy in Patients With Age-Related Macular Degeneration.

Science.gov (United States)

Dysli, Chantal; Wolf, Sebastian; Zinkernagel, Martin S

2016-05-01

To investigate fluorescence lifetime characteristics in patients with geographic atrophy (GA) in eyes with age-related macular degeneration and to correlate the measurements with clinical data and optical coherence tomography (OCT) findings. Patients with GA were imaged with a fluorescence lifetime imaging ophthalmoscope. Retinal autofluorescence lifetimes were measured in a short and a long spectral channel (498-560 nm and 560-720 nm). Mean retinal fluorescence lifetimes were analyzed within GA and the surrounding retina, and data were correlated with best corrected visual acuity and OCT measurements. Fluorescence lifetime maps of 41 eyes of 41 patients (80 ± 7 years) with GA were analyzed. Mean lifetimes within areas of atrophy were prolonged by 624 ± 276 ps (+152%) in the short spectral channel and 418 ± 186 ps (+83%) in the long spectral channel compared to the surrounding tissue. Autofluorescence lifetime abnormalities in GA occurred with particular patterns, similar to those seen in fundus autofluorescence intensity images. Within the fovea short mean autofluorescence lifetimes were observed, presumably representing macular pigment. Short lifetimes were preserved even in the absence of foveal sparing but were decreased in patients with advanced retinal atrophy in OCT. Short lifetimes in the fovea correlated with better best corrected visual acuity in both spectral channels. This study established that autofluorescence lifetime changes in GA present with explicit patterns. We hypothesize that the short lifetimes seen within the atrophy may be used to estimate damage induced by atrophy and to monitor disease progression in the context of natural history or interventional therapeutic studies.

Spent-fuel storage - MRS and/or on-site?

International Nuclear Information System (INIS)

Fuierer, A.A.

1991-01-01

The US government through the Office of Civilian Radioactive Waste Management (OCRWM) is seeking by the use of an authorized negotiator a site for a monitored retrievable storage (MRS) facility. Based on a public information document provided by the office of the negotiator, the MRS will be an integral part of the federal system for safe and permanent disposal of the nation's high-level radioactive wastes. It is planned that the MRS will accept and store spent fuel above ground until a repository opens and spent fuel that has been stored is shipped from the MRS to the repository. Additional spent fuel stored at reactor sites will be shipped to the MRS, which will be used as a staging area to assemble dedicated trains for shipment to the repository. The intent of the MRS is to reduce utilities' needs to expand on-site storage of spent fuel. A utility viewpoint may emphasize an alternate set of priorities. The waste management system must be considered as an overall system involving both the utility and DOE that begins with the first discharge of spent nuclear fuel from a commercial reactor and ends with high-level waste in a final repository. Many studies have been made on individual components of a waste system. This study, with the benefit of past hands-on experience as a guide, looks at costs and reliability for a total system concept with particular emphasis on the interface between the utility and Department of Energy

Singlet Exciton Lifetimes in Conjugated Polymer Films for Organic Solar Cells

KAUST Repository

Dimitrov, Stoichko

2016-01-13

The lifetime of singlet excitons in conjugated polymer films is a key factor taken into account during organic solar cell device optimization. It determines the singlet exciton diffusion lengths in polymer films and has a direct impact on the photocurrent generation by organic solar cell devices. However, very little is known about the material properties controlling the lifetimes of singlet excitons, with most of our knowledge originating from studies of small organic molecules. Herein, we provide a brief summary of the nature of the excited states in conjugated polymer films and then present an analysis of the singlet exciton lifetimes of 16 semiconducting polymers. The exciton lifetimes of seven of the studied polymers were measured using ultrafast transient absorption spectroscopy and compared to the lifetimes of seven of the most common photoactive polymers found in the literature. A plot of the logarithm of the rate of exciton decay vs. the polymer optical bandgap reveals a medium correlation between lifetime and bandgap, thus suggesting that the Energy Gap Law may be valid for these systems. This therefore suggests that small bandgap polymers can suffer from short exciton lifetimes, which may limit their performance in organic solar cell devices. In addition, the impact of film crystallinity on the exciton lifetime was assessed for a small bandgap diketopyrrolopyrrole co-polymer. It is observed that the increase of polymer film crystallinity leads to reduction in exciton lifetime and optical bandgap again in agreement with the Energy Gap Law.

Dry Refabrication Technology Development of Spent Nuclear Fuel

International Nuclear Information System (INIS)

Lee, Jung Won; Park, G. I.; Park, C. J.

2010-04-01

Key technical data on advanced nuclear fuel cycle technology development for the spent fuel recycling have been produced in this study. In the frame work of DUPIC, dry process oxide products fabrication, hot cell experimental data for decladding, powdering and oxide product fabrication from low and high burnup spent fuel have been produced, basic technology for fabrication of spent fuel standard material has been developed, and remote modulated welding equipment has been designed and fabricated. In the area of advanced pre-treatment process development, a rotary-type oxidizer and spherical particle fabrication process were developed by using SIMFUEL and off-gas treatment technology and zircalloy tube treatment technology were studied. In the area of the property characteristics of dry process products, fabrication technology of simulated dry process products was established and property models were developed based on reproducible property measurement data

A literature survey on the dissolution mechanism of spent fuel under disposal conditions

International Nuclear Information System (INIS)

Ollila, Kaija

1989-06-01

In Finland spent nuclear fuel is planned to be disposed of at large depths in crystalline bedrock. As part of the YJT (Nuclear Waste Commission of Finnish Power Companies) - program, the solubiliy and dissolution mechanisms of unirradiated UO 2 are experimentally investigated as a function of groundwater conditions. This study is a literature survey on the leaching and dissolution studies carried out with spent fuel. It consists first a review on characterization studies of spent fuel. Then the solubilities and release mechanisms of the radionuclides from spent fuel in granitic or related groundwaters are discussed, including the dissolution of UO 2 matrix, and the leaching of fission products and actinides. Lastly approaches to modelling the dissolution of spent fuel are shortly discussed

The role of technology, product lifetime, and energy efficiency in climate mitigation: A case study of air conditioners in Japan

International Nuclear Information System (INIS)

Nishijima, Daisuke

2017-01-01

This study analyzed the impact on the life-cycle CO_2 emissions derived from a specific durable good (i.e., household air conditioners in this study) of industrial technology changes, product lifetime changes, and energy efficiency improvements. I proposed a comprehensive structural decomposition analysis including two factors of average lifetime and energy efficiency trend of household air conditioners and applied the decomposition method to the Japanese environmental input-output tables of 1990, 1995, 2000, and 2005. The empirical results show that “Household air-conditioner sector” itself contributed to reducing life-cycle CO_2 emissions derived from household air conditioners, while other sectors such as “On-site power generation sector” and “Retail trade sector” contributed to increasing life-cycle CO_2 emissions derived from household air conditioners. I also conducted combined scenario analysis about reduction potential of product lifetime and energy efficiency of air conditioners and the results showed the reduction rate of energy efficiency necessary for maintain CO_2 emissions in 2005 at 1990 level on each average lifetime scenario. (e.g. if average lifetime of air conditioners is shortened by 1 year, energy efficiency of air conditioners have to be further improved by 20.6% from current level. - Highlights: • This study provides a decomposition framework for air conditioner’s CO_2 emissions. • Technology, product lifetime and energy efficiency are considered in the framework. • “Household air conditioner” sector contributed to reducing CO_2 emissions largely. • “On-site power generation” indirectly contributed to increasing CO_2 emissions. • I showed the improvement rates of energy efficiency to achieve a reduction target.

Status of the spent fuel dry storage programme for Cernavoda NPP

International Nuclear Information System (INIS)

Radu, M.

1999-01-01

The Cernavoda NPP Unit 1 (600 MWe Standard type) is in operation since December 1996. Within the framework of the R and D Radioactive Waste and Spent Fuel Management Programme, investigations, studies and research are carried out on site identification and conceptual designs for both a Spent Fuel Interim Storage Facility and a Spent Fuel Disposal Facility. The status of the work performed in the framework of this programme as well as the situation of the spent fuel resulting from the Research Institutes will be presented in the paper. (author)

Lifetime physical activity and female stress urinary incontinence.

Science.gov (United States)

Nygaard, Ingrid E; Shaw, Janet M; Bardsley, Tyler; Egger, Marlene J

2015-07-01

We sought to estimate whether moderate/severe stress urinary incontinence (SUI) in middle-aged women is associated with overall lifetime physical activity (including leisure, household, outdoor, and occupational), as well as lifetime leisure (recreational), lifetime strenuous, and strenuous activity during the teen years. Recruitment for this case-control study was conducted in primary-care-level family medicine and gynecology clinics. A total of 1538 enrolled women ages 39-65 years underwent a Pelvic Organ Prolapse Quantification examination to assess vaginal support. Based on Incontinence Severity Index scores, cases had moderate/severe and controls had no/mild SUI. We excluded 349 with vaginal descent at/below the hymen (pelvic organ prolapse), 194 who did not return questionnaires, and 110 with insufficient activity data for analysis. In all, 213 cases were frequency matched 1:1 by age group to controls. Physical activity was measured using the Lifetime Physical Activity Questionnaire, in which women recall activity from menarche to present. We created separate multivariable logistic regression models for activity measures. SUI odds increased slightly with overall lifetime activity (odds ratio [OR], 1.20 per 70 additional metabolic equivalent of task-h/wk; 95% confidence interval [CI], 1.02-1.41), and were not associated with lifetime strenuous activity (OR, 1.11; 95% CI, 0.99-1.25). In quintile analysis of lifetime leisure activity, which demonstrated a nonlinear pattern, all quintiles incurred about half the odds of SUI compared to reference (second quintile; P = .009). Greater strenuous activity in teen years modestly increased SUI odds (OR, 1.37 per 7 additional h/wk; 95% CI, 1.09-1.71); OR, 1.75; 95% CI, 1.15-2.66 in sensitivity analysis adjusting for measurement error. The predicted probability of SUI rose linearly in women exceeding 7.5 hours of strenuous activity/wk during teen years. Teen strenuous activity had a similar effect on SUI odds when

CVD grown 2D MoS{sub 2} layers: A photoluminescence and fluorescence lifetime imaging study

Energy Technology Data Exchange (ETDEWEB)

Oezden, Ayberk; Madenoglu, Buesra [Department of Materials Science and Engineering, Faculty of Engineering, Anadolu University, Eskisehir (Turkey); Sar, Hueseyin; Ay, Feridun; Perkgoez, Nihan Kosku [Department of Electrical and Electronics Engineering, Faculty of Engineering, Anadolu University, Eskisehir (Turkey); Yeltik, Aydan [Department of Physics, UNAM Institute of Materials Science and Nanotechnology, Bilkent University, Ankara (Turkey); Sevik, Cem [Department of Mechanical Engineering, Faculty of Engineering, Anadolu University, Eskisehir (Turkey)

2016-11-15

In this letter, we report on the fluorescence lifetime imaging and accompanying photoluminescence properties of a chemical vapour deposition (CVD) grown atomically thin material, MoS{sub 2}. μ-Raman, μ-photoluminescence (PL) and fluorescence lifetime imaging microscopy (FLIM) are utilized to probe the fluorescence lifetime and photoluminescence properties of individual flakes of MoS{sub 2} films. Usage of these three techniques allows identification of the grown layers, grain boundaries, structural defects and their relative effects on the PL and fluorescence lifetime spectra. Our investigation on individual monolayer flakes reveals a clear increase of the fluorescence lifetime from 0.3 ns to 0.45 ns at the edges with respect to interior region. On the other hand, investigation of the film layer reveals quenching of PL intensity and lifetime at the grain boundaries. These results could be important for applications where the activity of edges is important such as in photocatalytic water splitting. Finally, it has been demonstrated that PL mapping and FLIM are viable techniques for the investigation of the grain-boundaries. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Development of compaction technique for spent fuel skeletons

Energy Technology Data Exchange (ETDEWEB)

Yoon, Ji Sup; Kim, Young Hwan; Jung, Jae Hoo [Korea Atomic Energy Research Institute, Taejon (Korea)

1999-12-01

To increase the utilization of uranium resources contained in the spent fuel, the spent fuel is reused. For this, the spent fuel is dismantled or spent fuel rod is extracted from the spent fuel assembly. When the rod is extracted, the remaining components of spent fuel assembly, so called a NFBC(Non-Fuel Bearing Components), should be compacted for the final disposal. To this end, several companies developed the NFBC compactors. German company, named as GNS has developed the direct compression devices of the NFBCs for the rod consolidation and installed it at the PKA(2) of pilot conditioning plant. B and W (Babcock and Wilcox) in USA adopted cutting method rather than the compression method and developed the special cutting devices of NFBC which can be applied underwater environment. In this study the characteristics of these two methods was investigated, in terms of fabrication cost of devices, maintainability in a high radioactive environment, required power and work volume for operation. Also, the optimal power source is selected by comparing the maximum power versus the work volume for operation. In addition to these, the reduction ratio of the bulk volume is obtained while varying the cutting length of the NFBC through a series of experiments. Based on the results of analysis and experiments, the cutting method after compression is selected as an optimal volume reduction method and its design specification is obtained. 8 refs., 62 figs., 32 tabs. (Author)

Overview on spent fuel management strategies

International Nuclear Information System (INIS)

Dyck, P.

2002-01-01

This paper presents an overview on spent fuel management strategies which range from reprocessing to interim storage in a centralised facility followed by final disposal in a repository. In either case, more spent fuel storage capacity (wet or dry, at-reactor or away-from-reactor, national or regional) is required as spent fuel is continuously accumulated while most countries prefer to defer their decision to choose between these two strategies. (author)

Lifetime and past-year prevalence of children's exposure to violence in 9 Balkan countries: the BECAN study.

Science.gov (United States)

Nikolaidis, George; Petroulaki, Kiki; Zarokosta, Foteini; Tsirigoti, Antonia; Hazizaj, Altin; Cenko, Enila; Brkic-Smigoc, Jelena; Vajzovic, Emir; Stancheva, Vaska; Chincheva, Stefka; Ajdukovic, Marina; Rajter, Miro; Raleva, Marija; Trpcevska, Liljana; Roth, Maria; Antal, Imola; Ispanovic, Veronika; Hanak, Natasha; Olmezoglu-Sofuoglu, Zeynep; Umit-Bal, Ismail; Bianchi, Donata; Meinck, Franziska; Browne, Kevin

2018-01-01

Children's exposure to violence is a major public health issue. The Balkan epidemiological study on Child Abuse and Neglect project aimed to collect internationally comparable data on violence exposures in childhood. A three stage stratified random sample of 42,194 school-attending children (response rate: 66.7%) in three grades (aged 11, 13 and 16 years) was drawn from schools in Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Former Yugoslavian Republic of Macedonia (FYROM), Greece, Romania, Serbia and Turkey. Children completed the ICAST-C questionnaire, which measures children's exposure to violence by any perpetrator. Exposure rates for psychological violence were between 64.6% (FYROM) and 83.2% (Greece) for lifetime and 59.62% (Serbia) and 70.0% (Greece) for past-year prevalence. Physical violence exposure varied between 50.6% (FYROM) and 76.3% (Greece) for lifetime and 42.5% (FYROM) and 51.0% (Bosnia) for past-year prevalence. Sexual violence figures were highest for lifetime prevalence in Bosnia (18.6%) and lowest in FYROM (7.6%). Lifetime contact sexual violence was highest in Bosnia (9.8%) and lowest in Romania (3.6%). Past-year sexual violence and contact sexual violence prevalence was lowest in Romania (5.0 and 2.1%) and highest in Bosnia (13.6 and 7.7% respectively). Self-reported neglect was highest for both past-year and lifetime prevalence in Bosnia (48.0 and 20.3%) and lowest in Romania (22.6 and 16.7%). Experiences of positive parental practices were reported by most participating children in all countries. Where significant differences in violence exposure by sex were observed, males reported higher exposure to past-year and lifetime sexual violence and females higher exposure to neglect. Children in Balkan countries experience a high burden of violence victimization and national-level programming and child protection policy making is urgently needed to address this.

Survey of wet and dry spent fuel storage

International Nuclear Information System (INIS)

1999-07-01

Spent fuel storage is one of the important stages in the nuclear fuel cycle and stands among the most vital challenges for countries operating nuclear power plants. Continuous attention is being given by the IAEA to the collection, analysis and exchange of information on spent fuel management. Its role in this area is to provide a forum for exchanging information and for coordinating and encouraging closer co-operation among Member States. Spent fuel management is recognized as a high priority IAEA activity. In 1997, the annual spent fuel arising from all types of power reactors worldwide amounted to about 10,500 tonnes heavy metal (t HM). The total amount of spent fuel accumulated worldwide at the end of 1997 was about 200,000 t HM of which about 130,000 t HM of spent fuel is presently being stored in at-reactor (AR) or away-from-reactor (AFR) storage facilities awaiting either reprocessing or final disposal and 70,000 t HM has been reprocessed. Projections indicate that the cumulative amount generated by 2010 may surpass 340,000 t HM and by the year 2015 395,000 t HM. Part of the spent fuel will be reprocessed and some countries took the option to dispose their spent fuel in a repository. Most countries with nuclear programmes are using the deferral of a decision approach, a 'wait and see' strategy with interim storage, which provides the ability to monitor the storage continuously and to retrieve the spent fuel later for either direct disposal or reprocessing. Some countries use different approaches for different types of fuel. Today the worldwide reprocessing capacity is only a fraction of the total spent fuel arising and since no final repository has yet been constructed, there will be an increasing demand for interim storage. The present survey contains information on the basic storage technologies and facility types, experience with wet and dry storage of spent fuel and international experience in spent fuel transport. The main aim is to provide spent fuel

Utilization of Spent Resources in Support of Eco-Economic Decoupling in Central Java

Directory of Open Access Journals (Sweden)

Nuril Fikri Aulia

2015-09-01

Full Text Available Implementation of the development is often cause adverse environmental impacts. Adverse effects are environmental degradation and decreasing availability of resources. To overcome this, it is necessary that the development can still continue, the environment is not damaged, and the availability of resources is maintained. One effort is through eco - economic decoupling activities with the use of spent resources. The aim of study to determine the potential of spent resources in Central Java, knows the problems in the utilization of spent resources in Central Java, and to determine the impact of the utilization of spent resources in Central Java by a qualitative descriptive method. The results show that in the study have the potential of eco-economic decoupling indicated by the availability of spent resources and had done utilization of spent resources. However, this potential has not been optimally developed, because there are still some problems in its utilization. Problems in the use of spent resources are the lack of knowledge about eco-economic decoupling and spent resources among stakeholder, there is no specific policy on eco - economic decoupling, the lack of Local Government 's role in the utilization of spent resource, and the lack of synergy programs and activities in supporting the utilization of spent resources. Utilization of spent resources have positive impact to reduce pressure on the environment and natural resources, create a new job, and increase incomes for society.

Spent fuel interim management: 1995 update

International Nuclear Information System (INIS)

Anderson, C.K.

1995-01-01

The problems of interim away-from-reactor spent fuel storage and storage in spent fuel pools at the reactor site are discussed. An overview of the state-of-the-art in the USA, Europe, and Japan is presented. The technical facilities for away-from-reactor storage are briefly described, including wet storage pools, interactive concrete systems, metallic containers, and passive concrete systems. Reprocessing technologies are mostly at the design stage only. It is predicted that during the 20 years to come, about 50 000 tonnes of spent fuel will be stored at reactor sites regardless of the advance of spent fuel reprocessing or interim storage projects. (J.B.). 4 tabs., 2 figs

The burnup dependence of light water reactor spent fuel oxidation

International Nuclear Information System (INIS)

Hanson, B.D.

1998-07-01

Over the temperature range of interest for dry storage or for placement of spent fuel in a permanent repository under the conditions now being considered, UO 2 is thermodynamically unstable with respect to oxidation to higher oxides. The multiple valence states of uranium allow for the accommodation of interstitial oxygen atoms in the fuel matrix. A variety of stoichiometric and nonstoichiometric phases is therefore possible as the fuel oxidizers from UO 2 to higher oxides. The oxidation of UO 2 has been studied extensively for over 40 years. It has been shown that spent fuel and unirradiated UO 2 oxidize via different mechanisms and at different rates. The oxidation of LWR spent fuel from UO 2 to UO 2.4 was studied previously and is reasonably well understood. The study presented here was initiated to determine the mechanism and rate of oxidation from UO 2.4 to higher oxides. During the early stages of this work, a large variability in the oxidation behavior of samples oxidized under nearly identical conditions was found. Based on previous work on the effect of dopants on UO 2 oxidation and this initial variability, it was hypothesized that the substitution of fission product and actinide impurities for uranium atoms in the spent fuel matrix was the cause of the variable oxidation behavior. Since the impurity concentration is roughly proportional to the burnup of a specimen, the oxidation behavior of spent fuel was expected to be a function of both temperature and burnup. This report (1) summarizes the previous oxidation work for both unirradiated UO 2 and spent fuel (Section 2.2) and presents the theoretical basis for the burnup (i.e., impurity concentration) dependence of the rate of oxidation (Sections 2.3, 2.4, and 2.5), (2) describes the experimental approach (Section 3) and results (Section 4) for the current oxidation tests on spent fuel, and (3) establishes a simple model to determine the activation energies associated with spent fuel oxidation (Section 5)

Spent fuel management in Canada

International Nuclear Information System (INIS)

Khan, A.; Pattantyus, P.

1999-01-01

The current status of the Canadian spent fuel storage is presented. This includes wet and dry interim storage. Extension of wet interim storage facilities is nor planned, as dry technologies have found wide acceptance. The Canadian nuclear program is sustained by commercial Ontario Hydro CANDU type reactors, since 1971, representing 13600 MW(e) of installed capacity, able to produce 9200 spent fuel bundles (1800 tU) every year, and Hydro Quebec and New Brunswick CANDU reactors each producing 685 MW(e) and about 100 tU of spent fuel annually. The implementation of various interim (wt and dry) storage technologies resulted in simple, dense and low cost systems. Economical factors determined that the open cycle option be adopted for the CANDU type reactors rather that recycling the spent fuel. Research and development activities for immobilization and final disposal of nuclear waste are being undertaken in the Canadian Nuclear Fuel Waste Management Program

Lifetime-Aware Cloud Data Centers: Models and Performance Evaluation

Directory of Open Access Journals (Sweden)

Luca Chiaraviglio

2016-06-01

Full Text Available We present a model to evaluate the server lifetime in cloud data centers (DCs. In particular, when the server power level is decreased, the failure rate tends to be reduced as a consequence of the limited number of components powered on. However, the variation between the different power states triggers a failure rate increase. We therefore consider these two effects in a server lifetime model, subject to an energy-aware management policy. We then evaluate our model in a realistic case study. Our results show that the impact on the server lifetime is far from negligible. As a consequence, we argue that a lifetime-aware approach should be pursued to decide how and when to apply a power state change to a server.

Control system design specification of advanced spent fuel management process units

Energy Technology Data Exchange (ETDEWEB)

Ahn, S. H.; Kim, S. H.; Yoon, J. S

2003-06-01

In this study, the design specifications of instrumentation and control system for advanced spent fuel management process units are presented. The advanced spent fuel management process consists of several process units such as slitting device, dry pulverizing/mixing device, metallizer, etc. In this study, the control and operation characteristics of the advanced spent fuel management mockup process devices and the process devices developed in 2001 and 2002 are analysed. Also, a integral processing system of the unit process control signals is proposed, which the operation efficiency is improved. And a redundant PLC control system is constructed which the reliability is improved. A control scheme is proposed for the time delayed systems compensating the control performance degradation caused by time delay. The control system design specification is presented for the advanced spent fuel management process units. This design specifications can be effectively used for the detail design of the advanced spent fuel management process.

Development of advanced spent fuel management process. System analysis of advanced spent fuel management process

International Nuclear Information System (INIS)

Ro, S.G.; Kang, D.S.; Seo, C.S.; Lee, H.H.; Shin, Y.J.; Park, S.W.

1999-03-01

The system analysis of an advanced spent fuel management process to establish a non-proliferation model for the long-term spent fuel management is performed by comparing the several dry processes, such as a salt transport process, a lithium process, the IFR process developed in America, and DDP developed in Russia. In our system analysis, the non-proliferation concept is focused on the separation factor between uranium and plutonium and decontamination factors of products in each process, and the non-proliferation model for the long-term spent fuel management has finally been introduced. (Author). 29 refs., 17 tabs., 12 figs

Spent Fuel Test-Climax: technical measurements data management system description and data presentation

International Nuclear Information System (INIS)

Carlson, R.C.

1985-08-01

The Spent Fuel Test-Climax (SFT-C) was located 420 m below surface in the Climax Stock granite on the Nevada Test Site. The test was conducted under the technical direction of the Lawrence Livermore National Laboratory (LLNL) as part of the Nevada Nuclear Waste Storage Investigations (NNWSI) for the US Department of Energy. Eleven canisters of spent nuclear reactor fuel were emplaced, along with six electrical simulators, in April-May 1980. The spent fuel canisters were retrieved and the electrical simulators de-energized in March-April 1983. During the test, just over 1000 MW-hr of thermal energy was deposited in the site, causing temperature changes 100 0 C near the canisters, and about 5 0 in the tunnels. More than 900 channels of geotechnical, seismological, and test status data were recorded on nearly continuous basis for about 3-1/2 years, ending in September 1983. Most geotechnical instrumentation was known to be temperature sensitive, and thus would require temperature compensation before interpretation. Accordingly, a 10-in. reel of digital tape was off-loaded and shipped to Livermore every 4 to 8 weeks, where the data were verified, organized into 45 one-million-word files, and temperature corrected. The purpose of this report is to document the receipt and processing of the data by LLNL Livermore personnel, present facts about the history of the instruments which may be important to the interpretation of the data, present the data themselves in graphical form for each instrument over its operating lifetime, document the forms and locations in which the data will be archived, and offer the data to the geotechnical community for future use in understanding and predicting the effects of the storage of heat-generating waste in hard rocks such as granite

Development of a pico-second life-time spectrometer for positron annihilation studies

International Nuclear Information System (INIS)

Pujari, P.K.; Datta, T.; Tomar, B.S.; Das, S.K.

1992-01-01

Positron annihilation technique is a sensitive probe to investigate various physico-chemical phenomena due to the ability to provide information about the electron momentum and density in any medium. While measurements on the Doppler broadening and angular correlation of annihilation photons provide information about the electron momentum, the electron density at the annihilation site is obtained, by the positron life-time measurement. This report describes the development, optimization and calibration of a high resolution life-time spectrometer (FWHM=230 ps), based on fast-fast coincidence technique, a relatively new concept in nuclear timing spectroscopy. (author). 4 refs., 9 figs., 1 tab

Lifetime of piezoceramic multilayer actuators : interplay of material properties and actuator design

NARCIS (Netherlands)

Ende, D.A. van den; Bos, B.; Groen, W.A.; Dortmans, L.M.J.G.

2009-01-01

We report an investigation into factors limiting the functional lifetime of multilayer piezoceramic actuators. The study consists of a combination of lifetime experiments by means of an accelerated lifetime test, inspection of the actuator microstructure at different stages of the accelerated

Safeguardability assessment on pilot-scale advanced spent fuel conditioning facility

International Nuclear Information System (INIS)

Lee, S.Y.; Li, T.K.; Pickett, S.E.; Miller, M.C.; Ko, W.I.; Kim, H.D.

2006-01-01

Full text: In South Korea, approximately 6,000 metric tons of spent nuclear fuel from commercial reactor operation has been accumulated with the expectation of more than 30,000 metric tons, three times the present storage capacity, by the end of 2040. To resolve these challenges in spent fuel management, the Korea Atomic Energy Research Institute (KAERI) has been developing a dry reprocessing technology called Advanced Spent Fuel Conditioning Process (ACP). This is an electrometallurgical treatment technique to convert oxide-type spent fuel into a metallic form, and the electrolytic reduction (ER) technology developed recently is known as a more efficient concept for spent fuel conditioning. The goal of the ACP study is to recover more than 99% of the actinide elements into a metallic form with minimizing the volume and heat load of spent fuel. The significant reduction of the volume and heat load of spent fuel is expected to lighten the burden of final disposal in terms of disposal size, safety, and economics. In the framework of R and D collaboration for the ACP safeguards, a joint study on the safeguardability of the ACP technology has been performed by the Los Alamos National Laboratory (LANL) and KAERI. The purpose of this study is to address the safeguardability of the ACP technology, through analysis of material flow and development of a proper safeguards system that meet IAEA's comprehensive safeguards objective. The sub-processes and material flow of the pilot-scale ACP facility were analyzed, and subsequently the relevant material balance area (MBA) and key measurement point (KMP) were designed for material accounting. The uncertainties in material accounting were also estimated with international target values, and design requirements for the material accounting systems were derived

Automatic spent fuel ID number reader (I)

International Nuclear Information System (INIS)

Tanabe, S.; Kawamoto, H.; Fujimaki, K.; Kobe, A.

1991-01-01

An effective and efficient technique has been developed for facilitating identification works of LWR spent fuel stored in large scale spent fuel storage pools of such as processing plants. Experience shows that there are often difficulties in the implementation of operator's nuclear material accountancy and control works as well as safeguards inspections conducted on spent fuel assemblies stored in deep water pool. This paper reports that the technique is realized as an automatic spent fuel ID number reader system installed on fuel handling machine. The ID number reader system consists of an optical sub-system and an image processing sub-system. Thousands of spent fuel assemblies stored in under water open racks in each storage pool could be identified within relatively short time (e.g. within several hours) by using this combination. Various performance tests were carried out on image processing sub-system in 1990 using TV images obtained from different types of spent fuel assemblies stored in various storage pools of PWR and BWR power stations

Study on the effect of deposition rate and concentration of Eu on the fluorescent lifetime of CsI: Tl thin film

Energy Technology Data Exchange (ETDEWEB)

Xie, Yijun; Guo, Lina [University of Electronic Science and Technology of China, State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, Chengdu 610054 (China); Liu, Shuang, E-mail: shuangliu@uestc.edu.cn [University of Electronic Science and Technology of China, State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, Chengdu 610054 (China); Wang, Qianfeng; Zhang, Shangjian; Liu, Yong [University of Electronic Science and Technology of China, State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, Chengdu 610054 (China); Zhong, Zhiyong [University of Electronic Science and Technology of China, State Key Laboratory of Electronic Thin Films and Integrated Devices, Chengdu 610054 (China)

2017-06-21

Although there are many new scintillators being developed recently, CsI: Tl is still very efficient among them. The fluorescent lifetime is a very important parameter of CsI: Tl thin film and two series of experiments have been conducted to learn about it. Our experiments, however, have demonstrated that the deposition rate and the codoping of Eu{sup 2+} will significantly influence its fluorescent lifetime. In order to increase the efficiency of the imaging system, we intend to obtain a higher fluorescent lifetime for CsI: Tl thin film by controlling these two conditions. - Highlights: • We used vacuum vapor deposition method to grow the high-quality thin films. • The relationship between the deposition rate and the fluorescent lifetime of CsI: Tl thin film was tested. • Concentration of Eu on fluorescent lifetime of the CsI: Tl thin film was studied.

Lifetimes of charm and beauty hadrons

International Nuclear Information System (INIS)

Bellini, G.; Dornan, P.J.

1997-01-01

Major breakthroughs have been achieved in the determination of the lifetimes of charm and beauty hadrons. Much larger data samples than previously have become available and new experimental devices and techniques have been developed and employed. The lifetimes of all weakly decaying singly charmed hadrons have been measured, some with an accuracy of a few percent. The difference in the shortest lifetime - τ(Ω c ) - and the longest one - τ(D + ) - is given by a factor of close to ten. The experimental status of beauty lifetimes, while less complete, has still reached a new level of quality and is now better than 5% for the commoner states. New theoretical tools, based mainly on heavy quark expansions, have been developed; they incorporate as well as transcend earlier phenomenological descriptions. The observed pattern in the charm lifetime ratios is reproduced in a semi-quantitative manner as well as could be expected; as far as the beauty lifetime ratios are concerned some problems may well be emerging. The maturity level achieved in the measurements bodes quite well for future challenges where reliable and efficient tracking of the decay vertices will be crucial. (orig.)

Storage of LWR spent fuel in air: Volume 1: Design and operation of a spent fuel oxidation test facility

International Nuclear Information System (INIS)

Thornhill, C.K.; Campbell, T.K.; Thornhill, R.E.

1988-12-01

This report describes the design and operation and technical accomplishments of a spent-fuel oxidation test facility at the Pacific Northwest Laboratory. The objective of the experiments conducted in this facility was to develop a data base for determining spent-fuel dry storage temperature limits by characterizing the oxidation behavior of light-water reactor (LWR) spent fuels in air. These data are needed to support licensing of dry storage in air as an alternative to spent-fuel storage in water pools. They are to be used to develop and validate predictive models of spent-fuel behavior during dry air storage in an Independent Spent Fuel Storage Installation (ISFSI). The present licensed alternative to pool storage of spent fuel is dry storage in an inert gas environment, which is called inerted dry storage (IDS). Licensed air storage, however, would not require monitoring for maintenance of an inert-gas environment (which IDS requires) but does require the development of allowable temperature limits below which UO 2 oxidation in breached fuel rods would not become a problem. Scoping tests at PNL with nonirradiated UO 2 pellets and spent-fuel fragment specimens identified the need for a statistically designed test matrix with test temperatures bounding anticipated maximum acceptable air-storage temperatures. This facility was designed and operated to satisfy that need. 7 refs

Theoretical calculations of positron lifetimes for metal oxides

International Nuclear Information System (INIS)

Mizuno, Masataka; Araki, Hideki; Shirai, Yasuharu

2004-01-01

Our recent positron lifetime measurements for metal oxides suggest that positron lifetimes of bulk state in metal oxides are shorter than previously reported values. We have performed theoretical calculations of positron lifetimes for bulk and vacancy states in MgO and ZnO using first-principles electronic structure calculations and discuss the validity of positron lifetime calculations for insulators. By comparing the calculated positron lifetimes to the experimental values, it wa found that the semiconductor model well reproduces the experimental positron lifetime. The longer positron lifetime previously reported can be considered to arise from not only the bulk but also from the vacancy induced by impurities. In the case of cation vacancy, the calculated positron lifetime based on semiconductor model is shorter than the experimental value, which suggests that the inward relaxation occurs around the cation vacancy trapping the positron. (author)

Dose calculation for accident situations at WWR-S type spent nuclear fuel repository

International Nuclear Information System (INIS)

Margeanu, S.; Florescu, G.

2006-01-01

Full text: The Spent Nuclear Fuel Repository at IFIN-HH Bucharest (SNFR IFIN-HH) consists in four pools, repository hall, radiological monitoring system, ventilation system and auxiliary systems. At the moment the remaining activity in the repository is about 3500 Ci. Despite of the small activity, for emergency preparedness purposes, several accident scenarios, with a non zero probability of occurrence during the repository lifetime, have been postulated. Evaluations of radiological consequences to personnel, general public and environment, for each accident scenario have been performed. The radioactive inventory was evaluated with ORIGEN code from SCALE computer code system and radiological consequences were evaluated with COSYMA computer code. Assumptions for the source term determination, meteorological conditions and release, are presented. The calculated values of doses and risk are also presented. The impact of these accident scenarios on population and environment is also discussed. (authors)

Time Spent on Social Network Sites and Psychological Well-Being: A Meta-Analysis.

Science.gov (United States)

Huang, Chiungjung

2017-06-01

This meta-analysis examines the relationship between time spent on social networking sites and psychological well-being factors, namely self-esteem, life satisfaction, loneliness, and depression. Sixty-one studies consisting of 67 independent samples involving 19,652 participants were identified. The mean correlation between time spent on social networking sites and psychological well-being was low at r = -0.07. The correlations between time spent on social networking sites and positive indicators (self-esteem and life satisfaction) were close to 0, whereas those between time spent on social networking sites and negative indicators (depression and loneliness) were weak. The effects of publication outlet, site on which users spent time, scale of time spent, and participant age and gender were not significant. As most included studies used student samples, future research should be conducted to examine this relationship for adults.

Remote technology applications in spent fuel management

International Nuclear Information System (INIS)

2005-03-01

Spent fuel management has become a prospective area for application of remote technology in recent years with a steadily growing inventory of spent fuel arising from nuclear power production. A remark that could be made from the review of technical information collected from the IAEA meetings was that remote technology in spent fuel management has matured well through the past decades of industrial experiences. Various remote technologies have been developed and applied in the past for facility operation and maintenance work in spent fuel examination, storage, transportation, reprocessing and radioactive waste treatment, among others, with significant accomplishments in dose reduction to workers, enhancement of reliability, etc. While some developmental activities are continuing for more advanced applications, industrial practices have made use of simple and robust designs for most of the remote systems technology applications to spent fuel management. In the current state of affairs, equipment and services in remote technology are available in the market for applications to most of the projects in spent fuel management. It can be concluded that the issue of critical importance in remote systems engineering is to make an optimal selection of technology and equipment that would best satisfy the as low as reasonably achievable (ALARA) requirements in terms of relevant criteria like dose reduction, reliability, costs, etc. In fact, good selection methodology is the key to efficient implementation of remote systems applications in the modern globalized market. This TECDOC gives a review of the current status of remote technology applications for spent fuel management, based on country reports from some Member States presented at the consultancy meetings, of which updated reports are attached in the annex. The scope of the review covers the series of spent fuel handling operations involved in spent fuel management, from discharge from reactor to reprocessing or

Fluorescence lifetime evaluation of whole soils from the Amazon rainforest.

Science.gov (United States)

Nicolodelli, Gustavo; Tadini, Amanda Maria; Nogueira, Marcelo Saito; Pratavieira, Sebastião; Mounier, Stephane; Huaman, Jose Luis Clabel; Dos Santos, Cléber Hilário; Montes, Célia Regina; Milori, Débora Marcondes Bastos Pereira

2017-08-20

Time-resolved fluorescence spectroscopy (TRFS) is a new tool that can be used to investigate processes of interaction between metal ions and organic matter (OM) in soils, providing a specific analysis of the structure and dynamics of macromolecules. To the best of our knowledge, there are no studies in the literature reporting the use of this technique applied to whole/non-fractionated soil samples, making it a potential method for use in future studies. This work describes the use of TRFS to evaluate the fluorescence lifetimes of OM of whole soils from the Amazon region. Analysis was made of pellets of soils from an oxisol-spodosol system, collected in São Gabriel da Cachoeira (Amazonas, Brazil). The fluorescence lifetimes in the oxisol-spodosol system were attributed to two different fluorophores. One was related to complexation of an OM fraction with metals, resulting in a shorter fluorophore lifetime. A short fluorescence lifetime (2-12 ns) could be associated with simpler structures of the OM, while a long lifetime (19-66 ns) was associated with more complex OM structures. This new TRFS technique for analysis of the fluorescence lifetime in whole soil samples complies with the principles of green chemistry.

Studies on the Conditioning Methods of Spent Tri-butyl Phosphate/Kerosene and its Degradation Product in Different Matrices

International Nuclear Information System (INIS)

El-Dessouky, M.I.; El-sourougy, M.R.; Abed El-Aziz, M.M.; Aly, H.F.

1999-01-01

The destruction of spent TBP/Kerosene (odourless Kerosene (OK)) with potassium permanganate have been investigated. Comparative studies on the immobilization of spent TBP/Kerosene and its degradation product into different matrices have been carried out. The matrices used include, ordinary Portland cement, silica fume, treated fly ash, epoxy resin and cement mixed with epoxy resin.The different factors affecting solidified waste forms such as, compressive strength, water resistance, thermal stability, chemical resistance, radiological stability and leachability have been investigated. It was found that, epoxy resin and cement mixed with 5,10,20, and 50% of epoxy resin enhance the compressive strength of the solidified waste forms with spent TBP/OK more than that obtained from degradation products. The leaching rates of 152 and 154 Eu and 181 Hf from waste forms containing TBP/OK was found lower than that with degradation product

Study on burnup credit evaluation method at JAERI towards securing criticality safety rationale for management of spent fuel

International Nuclear Information System (INIS)

Nomura, Y.

1998-01-01

Lately, due to massive accumulation of spent fuel discharged from light water reactors in Japan, it is gradually demanded to introduce the so-called burnup credit methodology into criticality safety design for nuclear fuel cycle facilities, such as spent fuel storage pools and transport casks. In order to save space in the spent fuel storage pool of the Rokkasho Reprocessing Plant, the burnup credit design has been firstly implemented for its criticality safety evaluation. Here, its design conditions and operational control procedures are briefly shown and research using burned fuel at JAERI is explained to support its licensing safety review, focusing on the relevant content of the Nuclear Criticality Safety Handbook of Japan, which has been prepared so far and planned in the near future. Finally, international co-operation for study on burnup credit issues practiced by JAERI is addressed. (author)

DOE not planning to accept spent nuclear fuel

International Nuclear Information System (INIS)

Anon.

1995-01-01

Samuel K. Skinner, president of Commonwealth Edison Co. (ComEd), said open-quotes The federal government has a clear responsibility to begin accepting spent nuclear fuel in 1988,close quotes citing the Nuclear Waste Policy Act of 1982 before the Senate Energy and Natural Resources Committee. Based in Chicago, ComEd operates 12 nuclear units, making it the nation's largest nuclear utility. open-quotes Since 1983, the consumers who use electricity produced at all nuclear power plants have been paying to fund federal management of spent nuclear fuel. Consumer payments and obligations, with interest, now total more than $10 billion. Electricity consumers have held up their side of the deal. The federal government must do the same,close quotes Skinner added. Skinner represented the Nuclear Energy Institute (NEI) before the committee. NEI is the Washington-based trade association of the nuclear energy industries. For more than 12 years, utility customers have been paying one-tenth of a cent per kWhr to fund a federal spent fuel management program under the Nuclear Waste Policy Act of 1982. Under this act, the federal government assumed responsibility for management of spent fuel from the nation's nuclear power plants. The U.S. Department of Energy (DOE) was assigned to manage the storage and disposal program. DOE committed to begin accepting spent fuel from nuclear power plants by January 31, 1988. DOE has spent almost $5 million studying a site in Nevada, but is about 12 years behind schedule and does not plan to accept spent fuel beginning in 1998. DOE has said a permanent storage site will not be ready until 2010. This poses a major problem for many of the nation's nuclear power plants which supply about 20% of the electricity in the US

Optimal Taxation and Social Insurance in a Lifetime Perspective

DEFF Research Database (Denmark)

Bovenberg, A. Lans; Sørensen, Peter Birch

Advances in information technology have improved the administrative feasibility of redistribution based on lifetime earnings recorded at the time of retirement. We study optimal lifetime income taxation and social insurance in an economy in which redistributive taxation and social insurance serve...... to insure (ex ante) against skill heterogeneity as well as disability risk. Optimal disability benefits rise with previous earnings so that public transfers depend not only on current earnings but also on earnings in the past. Hence, lifetime taxation rather than annual taxation is optimal. The optimal tax...

Multiphoton autofluorescence lifetime imaging of induced pluripotent stem cells

Science.gov (United States)

Uchugonova, Aisada

2017-06-01

The multiphoton fluorescence lifetime imaging tomograph MPTflex with its flexible 360-deg scan head, articulated arm, and tunable femtosecond laser source was employed to study induced pluripotent stem cell (iPS) cultures. Autofluorescence (AF) lifetime imaging was performed with 250-ps temporal resolution and submicron spatial resolution using time-correlated single-photon counting. The two-photon excited AF was based on the metabolic coenzymes NAD(P)H and flavin adenine dinucleotide/flavoproteins. iPS cells generated from mouse embryonic fibroblasts (MEFs) and cocultured with growth-arrested MEFs as feeder cells have been studied. Significant differences on AF lifetime signatures were identified between iPS and feeder cells as well as between their differentiating counterparts.

The cascad spent fuel dry storage facility

International Nuclear Information System (INIS)

Guay, P.; Bonnet, C.

1991-01-01

France has a wide variety of experimental spent fuels different from LWR spent fuel discharged from commercial reactors. Reprocessing such fuels would thus require the development and construction of special facilities. The French Atomic Energy Commission (CEA) has consequently opted for long-term interim storage of these spent fuels over a period of 50 years. Comparative studies of different storage concepts have been conducted on the basis of safety (mainly containment barriers and cooling), economic, modular design and operating flexibility criteria. These studies have shown that dry storage in a concrete vault cooled by natural convection is the best solution. A research and development program including theoretical investigations and mock-up tests confirmed the feasibility of cooling by natural convection and the validity of design rules applied for fuel storage. A facility called CASCAD was built at the CEA's Cadarache Nuclear Research Center, where it has been operational since mid-1990. This paper describes the CASCAD facility and indicates how its concept can be applied to storage of LWR fuel assemblies

Lifetime of Organic Photovoltaics: Status and Predictions

DEFF Research Database (Denmark)

Gevorgyan, Suren; Madsen, Morten Vesterager; Roth, Bérenger

2016-01-01

The results of a meta-analysis conducted on organic photovoltaics (OPV) lifetime data reported in the literature is presented through the compilation of an extensive OPV lifetime database based on a large number of articles, followed by analysis of the large body of data. We fully reveal the prog......The results of a meta-analysis conducted on organic photovoltaics (OPV) lifetime data reported in the literature is presented through the compilation of an extensive OPV lifetime database based on a large number of articles, followed by analysis of the large body of data. We fully reveal...... the progress of reported OPV lifetimes. Furthermore, a generic lifetime marker has been defi ned, which helps with gauging and comparing the performance of different architectures and materials from the perspective of device stability. Based on the analysis, conclusions are drawn on the bottlenecks...

Burnup credit demands for spent fuel management in Ukraine

International Nuclear Information System (INIS)

Medun, V.

2001-01-01

In fact, till now, burnup credit has not be applied in Ukrainian nuclear power for spent fuel management systems (storage and transport). However, application of advanced fuel at VVER reactors, arising spent fuel amounts, represent burnup credit as an important resource to decrease spent fuel management costs. The paper describes spent fuel management status in Ukraine from viewpoint of subcriticality assurance under spent fuel storage and transport. It also considers: 1. Regulation basis concerning subcriticality assurance, 2. Basic spent fuel and transport casks characteristics, 3. Possibilities and demands for burnup credit application at spent fuel management systems in Ukraine. (author)

Development of nuclear spent fuel Maritime transportation scenario

International Nuclear Information System (INIS)

Yoo, Min; Kang, Hyun Gook

2014-01-01

Spent fuel transportation of South Korea is to be conducted through near sea because it is able to ship a large amount of the spent fuel far from the public comparing to overland transportation. The maritime transportation is expected to be increased and its risk has to be assessed. For the risk assessment, this study utilizes the probabilistic safety assessment (PSA) method and the notions of the combined event. Risk assessment of maritime transportation of spent fuel is not well developed in comparison with overland transportation. For the assessment, first, the transportation scenario should be developed and categorized. Categories are assorted into the locations, release aspects and exposure aspects. This study deals with accident that happens on voyage and concentrated on ship-ship collision. The collision accident scenario is generated with event tree analysis. The scenario will be exploited for the maritime transportation risk model which includes consequence and accident probability

Development of nuclear spent fuel Maritime transportation scenario

Energy Technology Data Exchange (ETDEWEB)

Yoo, Min; Kang, Hyun Gook [KAIST, Daejeon (Korea, Republic of)

2014-08-15

Spent fuel transportation of South Korea is to be conducted through near sea because it is able to ship a large amount of the spent fuel far from the public comparing to overland transportation. The maritime transportation is expected to be increased and its risk has to be assessed. For the risk assessment, this study utilizes the probabilistic safety assessment (PSA) method and the notions of the combined event. Risk assessment of maritime transportation of spent fuel is not well developed in comparison with overland transportation. For the assessment, first, the transportation scenario should be developed and categorized. Categories are assorted into the locations, release aspects and exposure aspects. This study deals with accident that happens on voyage and concentrated on ship-ship collision. The collision accident scenario is generated with event tree analysis. The scenario will be exploited for the maritime transportation risk model which includes consequence and accident probability.

Release of segregated nuclides from spent fuel

Energy Technology Data Exchange (ETDEWEB)

Johnson, L.H.; Tait, J.C. [Atomic Energy Canada Ltd., Pinawa, MB (Canada). Whiteshell Laboratories

1997-10-01

The potential release of fission and activation products from spent nuclear fuel into groundwater after container failure in the Swedish deep repository is discussed. Data from studies of fission gas release from representative Swedish BWR fuel are used to estimate the average fission gas release for the spent fuel population. Information from a variety of leaching studies on LWR and CANDU fuel are then reviewed as a basis for estimating the fraction of the inventory of key radionuclides that could be released preferentially (the Instant Release Fraction of IRF) upon failure of the fuel cladding. The uncertainties associated with these estimates are discussed. 33 refs, 6 figs, 3 tabs.

Spent fuel storage requirements 1993--2040

International Nuclear Information System (INIS)

1994-09-01

Historical inventories of spent fuel are combined with U.S. Department of Energy (DOE) projections of future discharges from commercial nuclear reactors in the United States to provide estimates of spent fuel storage requirements through the year 2040. The needs are estimated for storage capacity beyond that presently available in the reactor storage pools. These estimates incorporate the maximum capacities within current and planned in-pool storage facilities and any planned transshipments of spent fuel to other reactors or facilities. Existing and future dry storage facilities are also discussed. The nuclear utilities provide historical data through December 1992 on the end of reactor life are based on the DOE/Energy Information Administration (EIA) estimates of future nuclear capacity, generation, and spent fuel discharges

Electricite de France: Lifetime Project

International Nuclear Information System (INIS)

Combes, Jean-Pierre

1991-01-01

Electricite de France produces almost 80% of its electricity by means of standardized PWR nuclear power stations. Starting in 1986, therefore, a project known as the 'Lifetime Project' was developed, whose aim was initially to ensure that the lifetime defined at design stage (40 years in general) could be attained without major difficulty (follow up of the aging process). It then became apparent that it would be useful to know just how far it would be technically and economically possible to go. As a result, the project is now working towards increasing the lifetime of power stations. (author)

Risk assessment in spent fuel storage and transportation

International Nuclear Information System (INIS)

Pandimani, S.

1989-01-01

Risk assessment in various stages of nuclear fuel cycle is still an active area of Nuclear safety studies. From the results of risk assessment available in literature, it can be determined that the risk resulting from shipments of plutonium and spent-fuel are much greater than that resulting from the transport of other materials within the nuclear fuel cycle. In India spent fuels are kept in Spent Fuel Storage Pool (SFSP) for about 240-400 days, which is relatively a longer period compared to the usual 120 days as recommended by regulatory authorities. After cooling spent fuels are transported to the reprocessing sites which are mostly situated close to the plants. India has two high level waste treatment facilities, one PREFRE (Plutonium Reprocessing and Fuel Recycling) at Tarapur and the other one, a unit of Nuclear Fuel Complex at Hyderabad. This paper presents the risk associated with spent fuel storage and transportation for the Indian conditions. All calculations are based on a typical CANDU reactor system. Simple fault tree models are evolved for SFSP and for Transportation Accident Mode (TAM) for both road and rail. Fault tree quantification and risk assessment are done to each of these models. All necessary data for SFSP are taken mostly from Reactor Safety Study, (1975). Similarly, the data for rail TAM are taken from Annual Statistical Statements, (1987-8) and that for road TAM from Special Issue on Motor Vehicle Accident Statistics in India, (1986). Simulation method is used wherever necessary. Risk is also estimated for normal/accident free transport

Determination of the D mesons lifetimes

International Nuclear Information System (INIS)

Josa Mutuberria, M.I.

1990-01-01

The results from the experiment NA27, performed in the North Area of the Super Proton Synchrotron at CERN are presented. The experimental set up was the small, high resolution, rapid cyling bubble chamber LEBC coupled with the European Hybrid Spectrometer (EHS). More than 2 millions pictures were taken, with 1015000 in teractions in hydrogen. The stastistical sensitivity of the experiment was 38.5 events/μb. A clean sample of 700 charm particle decays was obtained. Estimators with minimal systematic and statistical errors are developed for the determination of the lifetimes of short-lived particles whose individual momenta are unknown. These estimators make use of the measured decay lengths and the a priori known production characteristics. In this way, it is possible to include identified but not fully reconstructed charm decays in the sample to determine their lifetime. The properties of these estimators were extensively studied by means of Montecarlo simulation. The detection of the short-lived particles through the impact parameter of their charged decay products leads to additional complications which are taken into account. The biases and statistical errors inherent in using simpler approximate lifetime estimators are also discussed. These estimators are applied to determine the lifetime of the D o and D +- mesons using the charm data sample from NA27. (Author)

Spent fuel shipping cask accident evaluation

International Nuclear Information System (INIS)

Fields, S.R.

1975-12-01

Mathematical models have been developed to simulate the dynamic behavior, following a hypothetical accident and fire, of typical casks designed for the rail shipment of spent fuel from nuclear reactors, and to determine the extent of radioactive releases under postulated conditions. The casks modeled were the IF-300, designed by the General Electric Company for the shipment of spent LWR fuel, and a cask designed by the Aerojet Manufacturing Company for the shipment of spent LMFBR fuel

Container for spent fuel assembly

International Nuclear Information System (INIS)

Sawai, Takeshi.

1996-01-01

The container of the present invention comprises a container main body having a body portion which can contain spent fuel assemblies and a lid, and heat pipes having an evaporation portion disposed along the outer surface of the spent fuel assemblies to be contained and a condensation portion exposed to the outside of the container main body. Further, the heat pipe is formed spirally at the evaporation portions so as to surround the outer circumference of the spent fuel assemblies, branched into a plurality of portions at the condensation portion, each of the branched portion of the condensation portion being exposed to the outside of the container main body, and is tightly in contact with the periphery of the slit portions disposed to the container main body. Then, since released after heat is transferred to the outside of the container main body from the evaporation portion of the heat pipe along the outer surface of the spent fuel assemblies by way of the condensation portion of the heat pipes exposed to the outside of the container main body, the efficiency of the heat transfer is extremely improved to enhance the effect of removing heat of spent fuel assemblies. Further, cooling effect is enhanced by the spiral form of the evaporation portion and the branched condensation portion. (N.H.)

Lifetime risk of atrial fibrillation according to optimal, borderline, or elevated levels of risk factors: cohort study based on longitudinal data from the Framingham Heart Study

Science.gov (United States)

Staerk, Laila; Wang, Biqi; Preis, Sarah R; Larson, Martin G; Lubitz, Steven A; Ellinor, Patrick T; McManus, David D; Ko, Darae; Weng, Lu-Chen; Lunetta, Kathryn L; Frost, Lars; Benjamin, Emelia J

2018-01-01

Abstract Objective To examine the association between risk factor burdens—categorized as optimal, borderline, or elevated—and the lifetime risk of atrial fibrillation. Design Community based cohort study. Setting Longitudinal data from the Framingham Heart Study. Participants Individuals free of atrial fibrillation at index ages 55, 65, and 75 years were assessed. Smoking, alcohol consumption, body mass index, blood pressure, diabetes, and history of heart failure or myocardial infarction were assessed as being optimal (that is, all risk factors were optimal), borderline (presence of borderline risk factors and absence of any elevated risk factor), or elevated (presence of at least one elevated risk factor) at index age. Main outcome measure Lifetime risk of atrial fibrillation at index age up to 95 years, accounting for the competing risk of death. Results At index age 55 years, the study sample comprised 5338 participants (2531 (47.4%) men). In this group, 247 (4.6%) had an optimal risk profile, 1415 (26.5%) had a borderline risk profile, and 3676 (68.9%) an elevated risk profile. The prevalence of elevated risk factors increased gradually when the index ages rose. For index age of 55 years, the lifetime risk of atrial fibrillation was 37.0% (95% confidence interval 34.3% to 39.6%). The lifetime risk of atrial fibrillation was 23.4% (12.8% to 34.5%) with an optimal risk profile, 33.4% (27.9% to 38.9%) with a borderline risk profile, and 38.4% (35.5% to 41.4%) with an elevated risk profile. Overall, participants with at least one elevated risk factor were associated with at least 37.8% lifetime risk of atrial fibrillation. The gradient in lifetime risk across risk factor burden was similar at index ages 65 and 75 years. Conclusions Regardless of index ages at 55, 65, or 75 years, an optimal risk factor profile was associated with a lifetime risk of atrial fibrillation of about one in five; this risk rose to more than one in three in individuals with at least

Radiological impacts of spent nuclear fuel management options. A comparative study

International Nuclear Information System (INIS)

2000-01-01

Given its potential significance for public health and the environment, the impact of radioactive releases during important steps of nuclear energy production must be considered when selecting among different fuel cycles. With this in mind, the OECD Nuclear Energy Agency (NEA) has undertaken a comparative study to the radiological impacts of two main fuel cycle options : one with and one without reprocessing of spent nuclear fuel. The study compares the respective impacts of the two options based on generic models and assumptions as well as actual data. It concludes that the difference between them is not significant. A wealth of recent data assembled and evaluated by an international expert team is provided in annex. (authors)

Study of the preparation of NI–Mn–Zn ferrite using spent NI–MH and alkaline Zn–Mn batteries

Energy Technology Data Exchange (ETDEWEB)

Xi, Guoxi, E-mail: xuhuidao1983@hotmail.com; Xi, Yuebin; Xu, Huidao, E-mail: xuhuidao1983@163.com; Wang, Lu

2016-01-15

Magnetic nanoparticles of Ni–Mn–Zn ferrite have been prepared by a sol–gel method making use of spent Ni–MH and Zn–Mn batteries as source materials. Characterization by X-ray diffraction was carried out to study the particle size. The presence of functional groups was identified by Fourier transform infrared spectroscopy. From studies by thermogravimetry and differential scanning calorimetry, crystallization occurred at temperatures above 560 °C. The magnetic properties of the final products were found to be directly influenced by the average particle size of the product. The M{sub s} values increase and the H{sub c} values decrease as the size of the Ni–Mn–Zn ferrite particles increases. - Highlights: • Ni–Mn–Zn ferrites could be prepared using spentbatteries as raw materials. • This work could provide an environmentally friendly process to recycle spent batteries. • The process could reduce cost and secondary pollution of spent batteries recycling. • The magnetic property of the ferrite could be controlled by changing the temperature.

A study for collaborative management for nuclear spent fuel control. Seeking for nuclear non-proliferation in East Asia

International Nuclear Information System (INIS)

1999-03-01

Because of the rapid increase of power generation with nuclear fuel in East Asia area, the management and control of nuclear spent fuel from nuclear reactors has become an essential and urgent issue in this area. This study focused on the possibility of forming an intergovernmental collaborative management system for nuclear spent fuel with an emphasize on nuclear non-proliferation among East Asian countries, i.e. China, Korea, Taiwan and Japan who own and operate nuclear power plants. First, we studied the present situation for nuclear spent fuel, including the storage measures, the future fore- cast on the accumulation and the government measures to deal with these spent fuel. Then, based upon first step studies, we examined the pros and cons when the collaborative management is realized particularly from the viewpoint of prevention of nuclear proliferation. Further, we estimated possible means for management and control of nuclear spent fuel, including its system size and cost. Finally, we extracted some technological tasks to be solved and political issues to be discussed. Our findings are as follows. 1. The total amount of the power generation in three East Asian counties (China, Korea and Taiwan) is about 17 million KW presently. This will be tripled to 51 million KW by the year 2010. When Japan's ability is added it is 62 million KW currently and 121 million by 2010. 2. The nuclear spent fuel in Taiwan and Korea will be saturated for their storage capacity. On the other hand, Japan will start to operate her reprocessing plant in Aomori prefecture in 2003 and her new storage capability is completed in 1999. Also in China, a reprocessing pilot plant is under construction and its operation is scheduled in 2001. 3. As their national policy, China and Japan does reprocess from spent fuel but Korea and Taiwan don't. Instead, they take non-reprocessing and direct geological disposal. 4. If the collaborative management of nuclear wastes is realized Multi

COMPARISON OF PHYSICO-CHEMICAL AND SENSORY QUALITY OF SAUSAGES PREPARED FROM SPENT DUCK AND HEN MEAT

Directory of Open Access Journals (Sweden)

Rajesh Kumar

2016-06-01

Full Text Available A study was conducted to assess the comparative quality of sausages prepared from different combination of spent duck and spent hen meats in terms of physico-chemical and sensory attributes. Sausages from 75% spent duck and 25% spent hen (T1 , 50% spent duck and 50% spent hen (T2 and 25% spent duck and 75% spent hen (T3 meats were prepared by standard methods. The quality parameter studies included pH, thiobarbituric acid (TBA, tyrosine value (TV, moisture (%, protein (%, fat (% and sensory attributes. Results revealed that pH, TV, and protein showed insignificant differences between the treatments whereas TBA, moisture and fat varied significantly (p T2 > T1.

Study for the selection of a supplementary spent fuel storage facility for KANUPP

International Nuclear Information System (INIS)

Ahmed, W.; Iqbal, M.J.; Arshad, M.

1999-01-01

Steps taken for construction of the spent fuel facility of Karachi Nuclear Power Plant (KANUPP) are the following: choice of conceptual design and site selection; preliminary design and preparation of Preliminary Safety Analysis Report (PSAR); Construction of the facility and preparation of PSAR; testing/commissioning and loading of the storage facility. Characterisation of the spent fuel is essential for design of the storage facility. After comparison of various storage types, it seems that construction of dry storage facility based on concrete canisters at KANUPP site is a suitable option to enhance the storage capacity

Spent fuel critical masses and supportive measurements

International Nuclear Information System (INIS)

Toffer, H.; Wells, A.H.

1987-01-01

Critical masses for spent fuel are larger than for green fuel and therefore use of the increased masses could result in improved handling, storage, and transport of such materials. To apply spent fuel critical masses requires an assessment of fuel exposure and the corresponding isotopic compositions. The paper discusses several approaches at the Hanford N Reactor in establishing fuel exposure, including a direct measurement of spent to green fuel critical masses. The benefits derived from the use of spent fuel critical masses are illustrated for cask designs at the Nuclear Assurance Corporation. (author)

Study of positron lifetime spectrum for Zn O varistor ceramics fabricated by Sol-gel route

International Nuclear Information System (INIS)

Li Xigui; Wei Shutao; Zhang Ruiying; Cheng Guosheng; Dai Xianqi; Zhang Jincang; Xing Huaimin

2000-01-01

An investigation of positron lifetime spectrum for ZnO varistor ceramics fabricated by Sol-gel route was carried out. The relationship between lifetime parameters and the densification and nonlinear coefficient α was given. The dependence of electrical properties on sintering temperature and duration was discussed

Study on uncertainty evaluation system for the safety evaluation of interim spent fuel storage facility

Energy Technology Data Exchange (ETDEWEB)

Kim, Myung Hyeon; Shin, Myeong Won; Rhy, Seok Jin; Cho, Dong Keon; Park, Dong Hwan [Kyunghee Univ., Seoul (Korea, Republic of); Cheong, Beom Jin [Minstry of Science and Technology, Gwacheon (Korea, Republic of)

1998-03-15

The main objective os to develop a technical standards for the facility operation of the interm, spent fuel storage facility and to develop a draft for the technical criteria to be legislated. The another objective os to define a uncertainty evaluation system for burn up credit application in criticality analysis and to investigate an applicability of this topic for future regulatory activity. Investigate a status of art for the operational criteria of spent fuel interm wet storage. Collect relevant laws, decree, notices and standards related to the operation of storage facility and study on the legislation system. Develop a draft of technical standards and criteria to be legislated. Define an evaluation system for the uncertainty analysis and study on the status of art in the field of criticality safety analysis. Develop an uncertainty evaluation system in criticality analysis with burnup credit and investigate an applicability as well as its benefits of this policy.

Lifetime of charge carriers in intrinsic indium antimonide

International Nuclear Information System (INIS)

Bruhns, H.; Kruse, H.

1980-01-01

The lifetime of additional photoinjected electron-hole pairs in intrinsic InSb at 291 K is investigated by measuring the photoconductive (PC) decay. Apart from studying the usual PC-decay an arangement is used with superimposed magnetic field transverse to the electric field. Depending on the direction of the magnetic field the photoinjected plasma is either driven into the sample's bulk or travels parallel to the illuminated surface. The Auger-lifetime is evaluated from the measurements by a numerical magnetohydrodynamical simulation taking into account surface recombination as well as the Suhl profile of the intrinsic plasma. A lifetime of tau = (57+-3) ns is found which is independent of the magnetic field up to 2.3 T. (author)

Spent fuel pyroprocessing demonstration

International Nuclear Information System (INIS)

McFarlane, L.F.; Lineberry, M.J.

1995-01-01

A major element of the shutdown of the US liquid metal reactor development program is managing the sodium-bonded spent metallic fuel from the Experimental Breeder Reactor-II to meet US environmental laws. Argonne National Laboratory has refurbished and equipped an existing hot cell facility for treating the spent fuel by a high-temperature electrochemical process commonly called pyroprocessing. Four products will be produced for storage and disposal. Two high-level waste forms will be produced and qualified for disposal of the fission and activation products. Uranium and transuranium alloys will be produced for storage pending a decision by the US Department of Energy on the fate of its plutonium and enriched uranium. Together these activities will demonstrate a unique electrochemical treatment technology for spent nuclear fuel. This technology potentially has significant economic and technical advantages over either conventional reprocessing or direct disposal as a high-level waste option

Radiation dose rates from commercial PWR and BWR spent fuel elements

International Nuclear Information System (INIS)

Willingham, C.E.

1981-10-01

Data on measurements of gamma dose rates from commercial reactor spent fuel were collected, and documented calculated gamma dose rates were reviewed. As part of this study, the gamma dose rate from spent fuel was estimated, using computational techniques similar to previous investigations into this problem. Comparison of the measured and calculated dose rates provided a recommended dose rate in air versus distance curve for PWR spent fuel

Initiation of depleted uranium oxide and spent fuel testing for the spent fuel sabotage aerosol ratio program

Energy Technology Data Exchange (ETDEWEB)

Molecke, M.A.; Gregson, M.W.; Sorenson, K.B. [Sandia National Labs. (United States); Billone, M.C.; Tsai, H. [Argonne National Lab. (United States); Koch, W.; Nolte, O. [Fraunhofer Inst. fuer Toxikologie und Experimentelle Medizin (Germany); Pretzsch, G.; Lange, F. [Gesellschaft fuer Anlagen- und Reaktorsicherheit (Germany); Autrusson, B.; Loiseau, O. [Inst. de Radioprotection et de Surete Nucleaire (France); Thompson, N.S.; Hibbs, R.S. [U.S. Dept. of Energy (United States); Young, F.I.; Mo, T. [U.S. Nuclear Regulatory Commission (United States)

2004-07-01

We provide a detailed overview of an ongoing, multinational test program that is developing aerosol data for some spent fuel sabotage scenarios on spent fuel transport and storage casks. Experiments are being performed to quantify the aerosolized materials plus volatilized fission products generated from actual spent fuel and surrogate material test rods, due to impact by a high energy density device, HEDD. The program participants in the U.S. plus Germany, France, and the U.K., part of the international Working Group for Sabotage Concerns of Transport and Storage Casks, WGSTSC have strongly supported and coordinated this research program. Sandia National Laboratories, SNL, has the lead role for conducting this research program; test program support is provided by both the U.S. Department of Energy and Nuclear Regulatory Commission. WGSTSC partners need this research to better understand potential radiological impacts from sabotage of nuclear material shipments and storage casks, and to support subsequent risk assessments, modeling, and preventative measures. We provide a summary of the overall, multi-phase test design and a description of all explosive containment and aerosol collection test components used. We focus on the recently initiated tests on ''surrogate'' spent fuel, unirradiated depleted uranium oxide, and forthcoming actual spent fuel tests. The depleted uranium oxide test rodlets were prepared by the Institut de Radioprotection et de Surete Nucleaire, in France. These surrogate test rodlets closely match the diameter of the test rodlets of actual spent fuel from the H.B. Robinson reactor (high burnup PWR fuel) and the Surry reactor (lower, medium burnup PWR fuel), generated from U.S. reactors. The characterization of the spent fuels and fabrication into short, pressurized rodlets has been performed by Argonne National Laboratory, for testing at SNL. The ratio of the aerosol and respirable particles released from HEDD-impacted spent

Review study 1995. Localization of the repository for spent nuclear fuel

International Nuclear Information System (INIS)

1995-10-01

This report gives an overview of the studies performed by SKB pertinent to selection of a site for the Swedish repository for spent nuclear fuels, and is written for both experts in the various fields involved, decision-makers and the interested general public. The review can not comprise all detailed factors necessary for deciding the localization, but deals mainly with conditions on the land surface and can point out areas which are not well suited or less interesting as a site. It also treats several scientific, technical and social bases in different parts of the country. 120 refs, 53 figs

Studies and research concerning BNFP design and construction of a spent-fuel disassembly/encapsulation system

International Nuclear Information System (INIS)

Dabolt, R.J.

1981-04-01

Commercial light water power reactor operation in the United States is developing a cumbersome inventory of spent fuel. Systems for interim storage and handling of this fuel are being developed by the Federal Government and industry. Disassembly and canning of the spent fuel elements is one of these systems. It has the potential to double the storage capacity of a prereprocessing storage facility or to triple the capacity of conventional shipping casks. Prototype equipment and controls required to perform this operation in a dry environment have been primarily designed and fabricated at the Barnwell Nuclear Fuel Plant (BNFP). Ridihalgh, Eggers, and Associates have provided design support and fabrication of the control system. This system is capable of extracting and canning the fuel pins and compacting the nonfuel-bearing components of spent fuel assemblies at processing rates of 10 to 12 assemblies per day. The process also provides the potential for enhanced inspection and assay of spent fuel by reducing the interference encountered from the high gamma fields of the nonfuel bearing hardware

5 CFR 551.422 - Time spent traveling.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Time spent traveling. 551.422 Section 551... Activities § 551.422 Time spent traveling. (a) Time spent traveling shall be considered hours of work if: (1... who is permitted to use an alternative mode of transportation, or an employee who travels at a time...

Spent fuel management newsletter. No. 2

International Nuclear Information System (INIS)

1993-04-01

This issue of the newsletter consists of two parts. The first part describes the IAEA Secretariat activities - work and programme of the Nuclear Materials and Fuel Cycle Technology Section of the Division of Nuclear Fuel Cycle and Waste Management, recent and planned meetings and publications, Technical Co-operation projects, Co-ordinated Research programmes. The second part contains country reports - national programmes on spent fuel management: current and planned storage and reprocessing capacities, spent fuel arisings, safety, transportation, storage and treatment of spent fuel

Spent fuel management newsletter. No. 2

Energy Technology Data Exchange (ETDEWEB)

NONE

1993-04-01

This issue of the newsletter consists of two parts. The first part describes the IAEA Secretariat activities - work and programme of the Nuclear Materials and Fuel Cycle Technology Section of the Division of Nuclear Fuel Cycle and Waste Management, recent and planned meetings and publications, Technical Co-operation projects, Co-ordinated Research programmes. The second part contains country reports - national programmes on spent fuel management: current and planned storage and reprocessing capacities, spent fuel arisings, safety, transportation, storage and treatment of spent fuel.

Pyrochemical processing of DOE spent nuclear fuel

International Nuclear Information System (INIS)

Laidler, J.J.

1995-01-01

A compact, efficient method for conditioning spent nuclear fuel is under development. This method, known as pyrochemical processing, or open-quotes pyroprocessing,close quotes provides a separation of fission products from the actinide elements present in spent fuel and further separates pure uranium from the transuranic elements. The process can facilitate the timely and environmentally-sound treatment of the highly diverse collection of spent fuel currently in the inventory of the United States Department of Energy (DOE). The pyroprocess utilizes elevated-temperature processes to prepare spent fuel for fission product separation; that separation is accomplished by a molten salt electrorefining step that provides efficient (>99.9%) separation of transuranics. The resultant waste forms from the pyroprocess, are stable under envisioned repository environment conditions and highly leach-resistant. Treatment of any spent fuel type produces a set of common high-level waste forms, one a mineral and the other a metal alloy, that can be readily qualified for repository disposal and avoid the substantial costs that would be associated with the qualification of the numerous spent fuel types included in the DOE inventory

Lifetime Improvement by Battery Scheduling

NARCIS (Netherlands)

Jongerden, M.R.; Schmitt, Jens B.; Haverkort, Boudewijn R.H.M.

The use of mobile devices is often limited by the lifetime of their batteries. For devices that have multiple batteries or that have the option to connect an extra battery, battery scheduling, thereby exploiting the recovery properties of the batteries, can help to extend the system lifetime. Due to

Characteristics of spent nuclear fuel

International Nuclear Information System (INIS)

Notz, K.J.

1988-04-01

The Office of Civilian Radioactive Waste Management (OCRWM) is responsible for the spent fuels and other wastes that will, or may, eventually be disposed of in a geological repository. The two major sources of these materials are commercial light-water reactor (LWR) spent fuel and immobilized high-level waste (HLW). Other wastes that may require long-term isolation include non-LWR spent fuels and miscellaneous sources such as activated metals. This report deals with spent fuels, but for completeness, the other sources are described briefly. Detailed characterizations are required for all of these potential repository wastes. These characteristics include physical, chemical, and radiological properties. The latter must take into account decay as a function of time. In addition, the present inventories and projected quantities of the various wastes are needed. This information has been assembled in a Characteristics Data Base which provides data in four formats: hard copy standard reports, menu-driven personal computer (PC) data bases, program-level PC data bases, and mainframe computer files. 5 refs., 3 figs., 4 tabs

NTL 11 spent fuel flask - meeting the challenge of regulatory and technological change

International Nuclear Information System (INIS)

Cory, A.R.

2004-01-01

By June 2005, when shipments of spent fuel for reprocessing from Germany are concluded, the NTL11 flask type will have been responsible for transporting a total of 1500 tonnes of heavy metal in the form of spent fuel. Excluding domestic transports in France and the UK, this represents 25% of the total European spent fuel transported for reprocessing since the flasks came into service in 1977. Approximately 40% of the total for the flask type will have been transported to BNFL's Sellafield facility, the remainder to Cogema at La Hague. The NTL11 flask can justifiably be described as being the workhorse of BNFL's European spent fuel transport business. The NTL11 flask started life under the ownership of Nuclear Transport Limited, an associate company of BNFL, and in recent years the original fleet of five flasks has been absorbed into the BNFL inventory. A recent build programme has seen a further four flasks added to the fleet, an expedient measure to cope with the additional transport requirements imposed by the need to meet the June 2005 deadline for the removal of contracted fuels from Germany. While there have been certain evolutionary changes affecting the package design, there have also been more significant changes in the Design Safety Case. These have sometimes been necessary to meet regulatory changes, or the challenges posed by the regulators. In other cases advantage has been taken of improvements in analytical techniques to demonstrate increased margins of operational safety. Where possible those margins have also been increased by other means, such as taking advantage of commercial trends to reduce package thermal loads. The NTL11 flask was designed around the reactor and fuel characteristics prevailing in the 1970's. Over the lifetime of the flask the responsible engineering teams have faced and met the successive challenges to develop the capability of the Package to face the changing requirements of the industry and the Transport Regulations. Both

Lifetime measurements in the picosecond range: Achievements and Perspectives

International Nuclear Information System (INIS)

Kruecken, Reiner

1999-01-01

This contribution will review the recoil distance method (RDM), its current range of applications as well as future perspectives for the measurement of lifetimes in the picosecond range of excited nuclear levels. Recent Doppler-shift lifetime experiments with large gamma-ray spectrometers have achieved a new level of precision and sensitivity, providing new insights into nuclear structure physics. High precision RDM measurements of near-yrast states in various mass regions have revealed dynamic shape effects beyond the framework of collective models and have also allowed to study the interaction between coexisting shapes. The measurement of lifetimes in superdeformed bands has shown that lifetimes can be measured for nuclear excitations, which are only populated with a few percent of the production cross-section of a nucleus. These experiments have also enabled us to study the mechanism of the decay-out of superdeformed bands. Another example for the need of precise lifetime measurements is the recent verifications of the concept of 'magnetic rotation' in nuclei by the experimental observation of the characteristic drop of B(M1) values as a function of angular momentum. These recent breakthroughs have also opened new perspectives for the use of the RDM technique for more exotic regions of nuclei and nuclear excitations. Here the measurement of lifetimes in neutron rich nuclei, which are not accessible with conventional nuclear reactions using stable beams and targets, is of special interest. Possible experimental approaches and simple estimates for the feasibility of such experiments will be presented. (author)

Long-term storage of spent nuclear fuel

International Nuclear Information System (INIS)

Kempe, T.F.; Martin, A.; Thorne, M.C.

1980-06-01

This report presents the results of a study on the storage of spent nuclear fuel, with particular reference to the options which would be available for long-term storage. Two reference programmes of nuclear power generation in the UK are defined and these are used as a basis for the projection of arisings of spent fuel and the storage capacity which might be needed. The characteristics of spent fuel which are relevant to long-term storage include the dimensions, materials and physical construction of the elements, their radioactive inventory and the associated decay heating as a function of time after removal from the reactor. Information on the behaviour of spent fuel in storage ponds is reviewed with particular reference to the corrosion of the cladding. The review indicates that, for long-term storage, both Magnox and AGR fuel would need to be packaged because of the high rate of cladding corrosion and the resulting radiological problems. The position on PWR fuel is less certain. Experience of dry storage is less extensive but it appears that the rate of corrosion of cladding is much lower than in water. Unit costs are discussed. Consideration is given to the radiological impact of fuel storage. (author)

Autofluorescence lifetime imaging during transoral robotic surgery: a clinical validation study of tumor detection (Conference Presentation)

Science.gov (United States)

Lagarto, João. L.; Phipps, Jennifer E.; Unger, Jakob; Faller, Leta M.; Gorpas, Dimitris; Ma, Dinglong M.; Bec, Julien; Moore, Michael G.; Bewley, Arnaud F.; Yankelevich, Diego R.; Sorger, Jonathan M.; Farwell, Gregory D.; Marcu, Laura

2017-02-01

Autofluorescence lifetime spectroscopy is a promising non-invasive label-free tool for characterization of biological tissues and shows potential to report structural and biochemical alterations in tissue owing to pathological transformations. In particular, when combined with fiber-optic based instruments, autofluorescence lifetime measurements can enhance intraoperative diagnosis and provide guidance in surgical procedures. We investigate the potential of a fiber-optic based multi-spectral time-resolved fluorescence spectroscopy instrument to characterize the autofluorescence fingerprint associated with histologic, morphologic and metabolic changes in tissue that can provide real-time contrast between healthy and tumor regions in vivo and guide clinicians during resection of diseased areas during transoral robotic surgery. To provide immediate feedback to the surgeons, we employ tracking of an aiming beam that co-registers our point measurements with the robot camera images and allows visualization of the surgical area augmented with autofluorescence lifetime data in the surgeon's console in real-time. For each patient, autofluorescence lifetime measurements were acquired from normal, diseased and surgically altered tissue, both in vivo (pre- and post-resection) and ex vivo. Initial results indicate tumor and normal regions can be distinguished based on changes in lifetime parameters measured in vivo, when the tumor is located superficially. In particular, results show that autofluorescence lifetime of tumor is shorter than that of normal tissue (p robot assisted cancer removal interventions.

Quantum system lifetimes and measurement perturbations

International Nuclear Information System (INIS)

Najakov, E.

1977-05-01

The recently proposed description of quantum system decay in terms of repeated measurement perturbations is modified. The possibility of retarded reductions to a unique quantum state, due to ineffective localization of the decay products at initial time measurements, is simply taken into account. The exponential decay law is verified again. A modified equation giving the observed lifetime in terms of unperturbed quantum decay law, measurement frequency and reduction law is derived. It predicts deviations of the observed lifetime from the umperturbed one, together with a dependence on experimental procedures. The influence of different model unperturbed decay laws and reduction laws on this effect is studied

Spent-fuel-storage alternatives

International Nuclear Information System (INIS)

1980-01-01

The Spent Fuel Storage Alternatives meeting was a technical forum in which 37 experts from 12 states discussed storage alternatives that are available or are under development. The subject matter was divided into the following five areas: techniques for increasing fuel storage density; dry storage of spent fuel; fuel characterization and conditioning; fuel storage operating experience; and storage and transport economics. Nineteen of the 21 papers which were presented at this meeting are included in this Proceedings. These have been abstracted and indexed

Measurement of the $\\Omega_{c}^{0}$ lifetime

CERN Document Server

Adamovich, M.I.; Alexandrov, Yu.A.; Barberis, D.; Beck, M.; Berat, C.; Beusch, W.; Boss, M.; Brons, S.; Bruckner, W.; Buenerd, M.; Buscher, C.; Charignon, F.; Chauvin, J.; Chudakov, E.A.; Dropmann, F.; Engelfried, J.; Faller, F.; Fournier, A.; Gerasimov, S.; Godbersen, M.; Grafstrom, P.; Haller, T.; Heidrich, M.; Hurst, R.B.; Konigsmann, Kay; Konorov, I.; Martens, K.; Martin, P.; Masciocchi, S.; Michaels, R.; Muller, U.; Newsom, C.; Paul, S.; Povh, B.; Ren, Z.; Rey-Campagnolle, M.; Rosner, G.; Rossi, L.; Rudolph, H.; Schmitt, L.; Siebert, H.W.; Simon, A.; Smith, V.J.; Thilmann, O.; Trombini, A.; Vesin, E.; Volkemer, B.; Vorwalter, K.; Walcher, T.; Walder, G.; Werding, R.; Wittmann, E.; Zavertyaev, M.V.

1995-01-01

We present the measurement of the lifetime of the Omega_c we have performed using three independent data samples from two different decay modes. Using a Sigma- beam of 340 GeV/c we have obtained clean signals for the Omega_c decaying into Xi- K- pi+ pi+ and Omega- pi+ pi- pi+, avoiding topological cuts normally used in charm analysis. The short but measurable lifetime of the Omega_c is demonstrated by a clear enhancement of the signals at short but finite decay lengths. Using a continuous maximum likelihood method we determined the lifetime to be tau(Omega_c) = 55 +13-11(stat) +18-23(syst) fs. This makes the Omega_c the shortest living weakly decaying particle observed so far. The short value of the lifetime confirms the predicted pattern of the charmed baryon lifetimes and demonstrates that the strong interaction plays a vital role in the lifetimes of charmed hadrons.

Lifetime improvement by battery scheduling

NARCIS (Netherlands)

Jongerden, M.R.; Haverkort, Boudewijn R.H.M.

The use of mobile devices is often limited by the lifetime of its battery. For devices that have multiple batteries or that have the option to connect an extra battery, battery scheduling, thereby exploiting the recovery properties of the batteries, can help to extend the system lifetime. Due to the

Positron lifetime spectroscopy of internally oxidised Ag-In alloys

International Nuclear Information System (INIS)

Wegner, D.; Lieb, K.P.

1989-01-01

The effects of In 2 O 3 precipitates on positron lifetimes after internal oxidation of α-Ag-In alloys have been investigated. A positron trap associated with the lifetime τ 205(3) ps was detected. On the basis of the experimental results obtained for different oxidation kinetics parameters, a trapping model is proposed according to which positrons thermalised in a dislocation field around oxide precipitates are trapped at the oxide/metal phase boundary. The transition from internal to external oxidation of Ag-In was also studied. The positron lifetime in In 2 O 3 was measured to be τ = 263(8) ps. (author)

Spent fuel's behavior under dynamic drip tests

International Nuclear Information System (INIS)

Finn, P.A.; Buck, E.C.; Hoh, J.C.; Bates, J.K.

1995-01-01

In the potential repository at Yucca Mountain, failure of the waste package container and the cladding of the spent nuclear fuel would expose the fuel to water under oxidizing conditions. To simulate the release behavior of radionuclides from spent fuel, dynamic drip and vapor tests with spent nuclear fuel have been ongoing for 2.5 years. Rapid alteration of the spent fuel has been noted with concurrent release of radionuclides. Colloidal species containing americium and plutonium have been found in the leachate. This observation suggests that colloidal transport of radionuclides should be included in the performance assessment of a potential repository

Positron annihilation lifetime studies of sol-gel transition of carrageenan gels

International Nuclear Information System (INIS)

Wakabayashi, Y.; Ito, K.; Li, H.L.; Ujihara, Y.

1996-01-01

Positron annihilation lifetime measurement was applied to study the sol-gel transition of anionic polysaccharide aqueous solutions in terms of free-volume parameters the size, intensity, and size distribution of free volumes of the gelation of K-form κ-carrageenan solutions as a function of temperature. Slight variations of free volume size and intensity against temperature were observed near 295 K. The correlation of free-volume data with other physical properties vibrational spectra (IR and Raman), conductivity, SAXS, elastic measurement, differential scanning calorimetry were investigated to understand the mechanism of sol-gel transition of carrageenan. (author)

Lifetime depression history and sexual function in women at midlife.

Science.gov (United States)

Cyranowski, Jill M; Bromberger, Joyce; Youk, Ada; Matthews, Karen; Kravitz, Howard M; Powell, Lynda H

2004-12-01

We examined the association between lifetime depression history and sexual function in a community-based sample of midlife women. Specifically, 914 women aged 42-52 who were participants in the Study of Women's Health Across the Nation completed a self-report assessment of their sexual behaviors, sexual desire, sexual arousal, and sexual satisfaction over the past 6 months. On the basis of the Structured Clinical Interview for the DSM-IV , participants were categorized into 1 of 3 lifetime major depressive disorder (MDD) history groups: no MDD history, single episode MDD, and recurrent MDD. In line with previous reports, women with a history of recurrent MDD reported experiencing less frequent sexual arousal, less physical pleasure, and less emotional satisfaction within their current sexual relationships. Although the groups did not differ in their reported frequency of sexual desire or partnered sexual behaviors, lifetime depression history was associated with increased rates of self-stimulation (masturbation). Associations between lifetime depression history and lower levels of physical pleasure within partnered sexual relationships and higher rates of masturbation remained significant following control for current depressive symptoms, study site, marital status, psychotropic medication use, and lifetime history of anxiety or substance abuse/dependence disorder. Future research is needed to characterize the temporal and etiologic relationships among lifetime depressive disorder, current mood state, and sexual function in women across the lifespan.

Positron lifetime calculation for the elements of the periodic table.

Science.gov (United States)

Campillo Robles, J M; Ogando, E; Plazaola, F

2007-04-30

Theoretical positron lifetime values have been calculated systematically for most of the elements of the periodic table. Self-consistent and non-self-consistent schemes have been used for the calculation of the electronic structure in the solid, as well as different parametrizations for the positron enhancement factor and correlation energy. The results obtained have been studied and compared with experimental data, confirming the theoretical trends. As is known, positron lifetimes in bulk show a periodic behaviour with atomic number. These calculations also confirm that monovacancy lifetimes follow the same behaviour. The effects of enhancement factors used in calculations have been commented upon. Finally, we have analysed the effects that f and d electrons have on positron lifetimes.

Positron lifetime calculation for the elements of the periodic table

International Nuclear Information System (INIS)

Robles, J M Campillo; Ogando, E; Plazaola, F

2007-01-01

Theoretical positron lifetime values have been calculated systematically for most of the elements of the periodic table. Self-consistent and non-self-consistent schemes have been used for the calculation of the electronic structure in the solid, as well as different parametrizations for the positron enhancement factor and correlation energy. The results obtained have been studied and compared with experimental data, confirming the theoretical trends. As is known, positron lifetimes in bulk show a periodic behaviour with atomic number. These calculations also confirm that monovacancy lifetimes follow the same behaviour. The effects of enhancement factors used in calculations have been commented upon. Finally, we have analysed the effects that f and d electrons have on positron lifetimes

Conceptual design of the handling and storage system for spent target vessel

Energy Technology Data Exchange (ETDEWEB)

Adachi, Junichi; Sasaki, Shinobu; Kaminaga, Masanori; Hino, Ryutaro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2001-03-01

A conceptual design of a handling and storage system for spent target vessels has been carried out, in order to establish spent target technology for the neutron scattering facility. The spent target vessels must be treated remotely with high reliability and safety, since they are highly activated and contain the poisonous mercury. The system is composed of a target exchange trolley to exchange the target vessel, remote handling equipment such as manipulators, airtight casks for the spent target vessel, storage pits and so on. This report presents the results of conceptual design study on a basic plan, a handling procedure, main devices and their arrangement of a handling and storage system for the spent target vessels. (author)

Study on Public and Stakeholder Engagement Process for Spent Nuclear Fuel Management

International Nuclear Information System (INIS)

Hwang, Yong Soo; Kim, Youn Ok; Han, Ji Woong; Jeong, Mi Seon; Kang, Chul Hyung

2007-07-01

To take lessons from foreign cases, Canada, Britain, and France which conducted their PSE programs successfully, the report examined their whole PSE process with their reports. Based on the advantageous factors from those countries, and also considering the other facts which are only applied to the Korean case, we developed the Korean version of PSE program. This PSE program created through this study is expected to be used as a possible example of PSE process for the Spent Nuclear Fuel Management in the near future

Alternative Concept to Enhance the Disposal Efficiency for CANDU Spent Fuel Disposal System

International Nuclear Information System (INIS)

Lee, Jong Youl; Cho, Dong Geun; Kook, Dong Hak; Lee, Min Soo; Choi, Heui Joo

2011-01-01

There are two types of nuclear reactors in Korea and they are PWR type and CANDU type. The safe management of the spent fuels from these reactors is very important factor to maintain the sustainable energy supply with nuclear power plant. In Korea, a reference disposal system for the spent fuels has been developed through a study on the direct disposal of the PWR and CANDU spent fuel. Recently, the research on the demonstration and the efficiency analyses of the disposal system has been performed to make the disposal system safer and more economic. PWR spent fuels which include a lot of reusable material can be considered being recycled and a study on the disposal of HLW from this recycling process is being performed. CANDU spent fuels are considered being disposed of directly in deep geological formation, since they have little reusable material. In this study, based on the Korean Reference spent fuel disposal System (KRS) which was to dispose of both PWR type and CANDU type, the more effective CANDU spent fuel disposal systems were developed. To do this, the disposal canister for CANDU spent fuels was modified to hold the storage basket for 60 bundles which is used in nuclear power plant. With these modified disposal canister concepts, the disposal concepts to meet the thermal requirement that the temperature of the buffer materials should not be over 100 .deg. C were developed. These disposal concepts were reviewed and analyzed in terms of disposal effective factors which were thermal effectiveness, U-density, disposal area, excavation volume, material volume etc. and the most effective concept was proposed. The results of this study will be used in the development of various wastes disposal system together with the HLW wastes from the PWR spent fuel recycling process.

Analysis of burnable poison in Ford Nuclear Reactor fuel to extend fuel lifetime. Final report, August 1, 1994--September 29, 1996

Energy Technology Data Exchange (ETDEWEB)

Burn, R.R.; Lee, J.C.

1996-12-01

The objective of the project was to establish the feasibility of extending the lifetime of fuel elements for the Ford Nuclear Reactor (FNR) by replacing current aluminide fuel with silicide fuel comprising a heavier uranium loading but with the same fissile enrichment of 19.5 wt% {sup 235}U. The project has focused on fuel designs where burnable absorbers, in the form of B{sub 4}C, are admixed with uranium silicide in fuel plates so that increases in the control reactivity requirements and peak power density, due to the heavier fuel loading, may be minimized. The authors have developed equilibrium cycle models simulating current full-size aluminide core configurations with 43 {approximately} 45 fuel elements. Adequacy of the overall equilibrium cycle approach has been verified through comparison with recent FNR experience in spent fuel discharge rates and simulation of reactor physics characteristics for two representative cycles. Fuel cycle studies have been performed to compare equilibrium cycle characteristics of silicide fuel designs, including burnable absorbers, with current aluminide fuel. These equilibrium cycle studies have established the feasibility of doubling the fuel element lifetime, with minimal perturbations to the control reactivity requirements and peak power density, by judicious additions of burnable absorbers to silicide fuel. Further study will be required to investigate a more practical silicide fuel design, which incorporates burnable absorbers in side plates of each fuel element rather than uniformly mixes them in fuel plates.

Effect of the final-state interaction on the initial core-hole lifetime: the case of the 4s-hole lifetime of Sn metal

International Nuclear Information System (INIS)

Ohno, Masahide

2003-01-01

The first theoretical study of the effect of the final-state interaction on the initial core-hole lifetime is presented. The 4s-hole lifetime width of Sn metal is calculated by an ab-initio atomic many-body theory (Green's function method). When the final-state interaction in the 4p4d two-hole state, created by the 4s -1 -4p -1 4d -1 εf super Coster-Kronig (CK) transition of the initial 4s hole, is explicitly taken into account, the ab-initio atomic many-body calculation of the 4s-hole X-ray photoelectron spectroscopy (XPS) spectrum of Sn atom can provide excellent agreement with experiment in both the 4s-hole energy and the 4s-hole lifetime width. Otherwise, the many-body calculation underestimates considerably the 4s-hole lifetime width. The 4p4d two-hole state interacts strongly with the 4d triple-hole state by the 4p -1 4d -1 -4d -3 εf super CK transition. The interaction affects greatly the initial 4s-hole lifetime width

Two-step sequential pretreatment for the enhanced enzymatic hydrolysis of coffee spent waste.

Science.gov (United States)

Ravindran, Rajeev; Jaiswal, Swarna; Abu-Ghannam, Nissreen; Jaiswal, Amit K

2017-09-01

In the present study, eight different pretreatments of varying nature (physical, chemical and physico-chemical) followed by a sequential, combinatorial pretreatment strategy was applied to spent coffee waste to attain maximum sugar yield. Pretreated samples were analysed for total reducing sugar, individual sugars and generation of inhibitory compounds such as furfural and hydroxymethyl furfural (HMF) which can hinder microbial growth and enzyme activity. Native spent coffee waste was high in hemicellulose content. Galactose was found to be the predominant sugar in spent coffee waste. Results showed that sequential pretreatment yielded 350.12mg of reducing sugar/g of substrate, which was 1.7-fold higher than in native spent coffee waste (203.4mg/g of substrate). Furthermore, extensive delignification was achieved using sequential pretreatment strategy. XRD, FTIR, and DSC profiles of the pretreated substrates were studied to analyse the various changes incurred in sequentially pretreated spent coffee waste as opposed to native spent coffee waste. Copyright © 2017 Elsevier Ltd. All rights reserved.

Quantum lifetime in electron storage rings

International Nuclear Information System (INIS)

Chao, A.W.

1977-02-01

One of the mechanisms which contribute to beam lifetime in electron storage rings is the quantum emission of energetic photons causing particles to be lost from the rf bucket. This quantum lifetime is among other things important in defining the required aperture in a storage ring. An approximate expression of quantum lifetime, predicted by a one-dimensional model which takes into account only the betatron motion, has been used in most storage ring designs. If the beam is aperture-limited at a position with nonzero dispersion, both the betatron and synchrotron motions have to be included and a two-dimensional model must be used. An exact expression of quantum lifetime for the one-dimensional case and an approximate expression for the two-dimensional case are given

Quantum lifetime in electron storage rings

International Nuclear Information System (INIS)

Chao, A.W.

1977-01-01

One of the mechanisms which contributes to beam lifetime in electron storage rings is the quantum emission of energetic photons causing particles to be lost from the rf bucket. This quantum lifetime is among other things important in defining the required aperture in a storage ring. An approximate expression of quantum lifetime, predicted by a one-dimensional model which takes into account only the betatron motion, has been used in most storage ring designs. If the beam is aperture-limited at a position with nonzero dispersion, both the betatron and synchrotron motions have to be included, and a two-dimensional model must be used. An exact expression of quantum lifetime for the one-dimensional case and an approximate expression for the two-dimensional case are given

Application of positron annihilation lifetime technique for {gamma}-irradiation stresses study in chalcogenide vitreous semiconductors

Energy Technology Data Exchange (ETDEWEB)

Shpotyuk, O.; Golovchak, R.; Kovalskiy, A. [Scientific Research Company ' ' Carat' ' , Stryjska str. 20279031 Lviv (Ukraine); Filipecki, J.; Hyla, M. [Physics Institute, Pedagogical University, Al. Armii Krajowej 13/1542201 Czestochowa (Poland)

2002-08-01

The influence of {gamma}-irradiation on the positron annihilation lifetime spectra in chalcogenide vitreous semiconductors of As-Ge-S system has been analysed. The correlations between lifetime data, structural features and chemical compositions of glasses have been discussed. The observed lifetime components are connected with bulk positron annihilation and positron annihilation on various native and {gamma}-induced open volume defects. It is concluded that after {gamma}-irradiation of investigated materials the {gamma}-induced microvoids based on S{sub 1}{sup -}, As{sub 2}{sup -}, and Ge{sub 3}{sup -} coordination defects play the major role in positron annihilation processes. (Abstract Copyright[2002], Wiley Periodicals, Inc.)

Inequivalence of single-particle and population lifetimes in a cuprate superconductor

Energy Technology Data Exchange (ETDEWEB)

Yang, Shuolong [SLAC National Accelerator Lab., Menlo Park, CA (United States); Stanford Univ., Stanford, CA (United States); Sobota, J. A. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Leuenberger, D. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Stanford Univ., Stanford, CA (United States); He, Y. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Stanford Univ., Stanford, CA (United States); Hashimoto, M. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Lu, D. H. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Eisaki, H. [National Institute of Advanced Industrial Science and Technology, Ibaraki (Japan); Kirchmann, P. S. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Shen, Z. -X. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Stanford Univ., Stanford, CA (United States)

2015-06-15

We study optimally doped Bi-2212 (T_c=96 K) using femtosecond time- and angle-resolved photoelectron spectroscopy. Energy-resolved population lifetimes are extracted and compared with single-particle lifetimes measured by equilibrium photoemission. The population lifetimes deviate from the single-particle lifetimes in the low excitation limit by 1–2 orders of magnitude. Fundamental considerations of electron scattering unveil that these two lifetimes are in general distinct, yet for systems with only electron-phonon scattering they should converge in the low-temperature, low-fluence limit. As a result, the qualitative disparity in our data, even in this limit, suggests that scattering channels beyond electron-phonon interactions play a significant role in the electron dynamics of cuprate superconductors.

A Lifetime's Adventure in Extracellular K+ Regulation: The Scottish Connection.

Science.gov (United States)

Brown, Angus M

2017-09-01

In a career that has spanned 45 years and shows no signs of slowing down, Dr Bruce Ransom has devoted considerable time and energy to studying regulation of interstitial K + . When Bruce commenced his studies in 1969 virtually nothing was known of the functions of glial cells, but Bruce's research contributed to the physiological assignation of function to mammalian astrocytes, namely interstitial K + buffering. The experiments that I describe in this review concern the response of the membrane potential (Em) of in vivo cat cortical astrocytes to changes in [K + ] o , an experimental manoeuvre that was achieved in two different ways. The first involved recording the Em of an astrocyte while the initial aCSF was switched to one with different K + , whereas in the second series of experiments the cortex was stimulated and the response of the astrocyte Em to the K + released from neighbouring neurons was recorded. The astrocytes responded in a qualitatively predictable manner, but quantitatively the changes were not as predicted by the Nernst equation. Elevations in interstitial K + are not sustained and K + returns to baseline rapidly due to the buffering capacity of astrocytes, a phenomenon studied by Bruce, and his son Chris, published 27 years after Bruce's initial publications. Thus, a lifetime spent investigating K + buffering has seen enormous advances in glial research, from the time cells were identified as 'presumed' glial cells or 'silent cells', to the present day, where glial cells are recognised as contributing to every important physiological brain function.

Storage of LWR spent fuel in air. Volume 3, Results from exposure of spent fuel to fluorine-contaminated air

Energy Technology Data Exchange (ETDEWEB)

Cunningham, M.E.; Thomas, L.E.

1995-06-01

The Behavior of Spent Fuel in Storage (BSFS) Project has conducted research to develop data on spent nuclear fuel (irradiated U0{sub 2}) that could be used to support design, licensing, and operation of dry storage installations. Test Series B conducted by the BSFS Project was designed as a long-term study of the oxidation of spent fuel exposed to air. It was discovered after the exposures were completed in September 1990 that the test specimens had been exposed to an atmosphere of bottled air contaminated with an unknown quantity of fluorine. This exposure resulted in the test specimens reacting with both the oxygen and the fluorine in the oven atmospheres. The apparent source of the fluorine was gamma radiation-induced chemical decomposition of the fluoro-elastomer gaskets used to seal the oven doors. This chemical decomposition apparently released hydrofluoric acid (HF) vapor into the oven atmospheres. Because the Test Series B specimens were exposed to a fluorine-contaminated oven atmosphere and reacted with the fluorine, it is recommended that the Test Series B data not be used to develop time-temperature limits for exposure of spent nuclear fuel to air. This report has been prepared to document Test Series B and present the collected data and observations.

Storage of LWR spent fuel in air. Volume 3, Results from exposure of spent fuel to fluorine-contaminated air

International Nuclear Information System (INIS)

Cunningham, M.E.; Thomas, L.E.

1995-06-01

The Behavior of Spent Fuel in Storage (BSFS) Project has conducted research to develop data on spent nuclear fuel (irradiated U0 2 ) that could be used to support design, licensing, and operation of dry storage installations. Test Series B conducted by the BSFS Project was designed as a long-term study of the oxidation of spent fuel exposed to air. It was discovered after the exposures were completed in September 1990 that the test specimens had been exposed to an atmosphere of bottled air contaminated with an unknown quantity of fluorine. This exposure resulted in the test specimens reacting with both the oxygen and the fluorine in the oven atmospheres. The apparent source of the fluorine was gamma radiation-induced chemical decomposition of the fluoro-elastomer gaskets used to seal the oven doors. This chemical decomposition apparently released hydrofluoric acid (HF) vapor into the oven atmospheres. Because the Test Series B specimens were exposed to a fluorine-contaminated oven atmosphere and reacted with the fluorine, it is recommended that the Test Series B data not be used to develop time-temperature limits for exposure of spent nuclear fuel to air. This report has been prepared to document Test Series B and present the collected data and observations

NEPA implementation: The Department of Energy's program to manage spent nuclear fuel

International Nuclear Information System (INIS)

Shipler, D.B.

1994-05-01

The Department of Energy (DOE) is implementing the National Environmental Protection Act (NEPA) in its management of spent nuclear fuel. The DOE strategy is to address the short-term safety concerns about existing spent nuclear fuel, to study alternatives for interim storage, and to develop a long-range program to manage spent nuclear fuel. This paper discusses the NEPA process, the environmental impact statements for specific sites as well as the overall program, the inventory of DOE spent nuclear fuel, the alternatives for managing the fuel, and the schedule for implementing the program

Study of creep-fatigue behavior in a 1000 MW rotor using a phenomenological lifetime model

Energy Technology Data Exchange (ETDEWEB)

Zhao, Nailong; Wang, Weizhe; Jiang, Jishen; Liu, Yingzheng [School of Mechanical Engineering, Shanghai (China)

2017-02-15

In this study, the phenomenological lifetime model was applied to part of an ultra-supercritical steam turbine rotor model to predict its lifetime as a post processing of the finite element method. To validate the accuracy and adaptation of the post processing program, stress strain hysteresis loops of a cylinderal model under service-like load cycle conditions in cycle N = 1 and 300 were constructed, and the comparison of the results with experimental data on the same cylinderal specimen showed them to be satisfactory. The temperature and von Mises stress distributions of the rotor during a startup-running-shutdown-natural cool process were numerically studied using ABAQUS and the damage caused by the interaction of creep and fatigue was subsequently computed and discussed. It was found that the maximum damage appeared at the inlet notch zone, with the blade groove areas and the front notch areas also suffering a large damage amplitude.

Storing the world's spent nuclear fuel

International Nuclear Information System (INIS)

Barkenbus, J.N.; Weinberg, A.M.; Alonso, M.

1985-01-01

Given the world's prodigious future energy requirements and the inevitable depletion of oil and gas, it would be foolhardy consciously to seek limitations on the growth of nuclear power. Indeed, the authors continue to believe that the global nuclear power enterprise, as measured by installed reactor capacity, can become much larger in the future without increasing proliferation risks. To accomplish this objective will require renewed dedication to the non-proliferation regime, and it will require some new initiatives. Foremost among these would be the establishment of a spent fuel take-back service, in which one or a few states would retrieve spent nuclear fuel from nations generating it. The centralized retrieval of spent fuel would remove accessible plutonium from the control of national leaders in non-nuclear-weapons states, thereby eliminating the temptation to use this material for weapons. The Soviets already implement a retrieval policy with the spent fuel generated by East European allies. The authors believe that it is time for the US to reopen the issue of spent-fuel retrieval, and thus to strengthen its non-proliferation policies and the nonproliferation regime in general. 7 references

Effects of alpha-decay on spent fuel corrosion behaviour

International Nuclear Information System (INIS)

Wiss, T.; Rondinella, V.V.; Cobos, J.; Wegen, D.H.; Amme, M.; Ronchi, C.

2004-01-01

An overview of results in the area of spent fuel characterization as nuclear waste is presented. These studies are focused on primary aspects of spent fuel corrosion, by considering different fuel compositions and burn ups, as well as a wide set of environmental conditions. The key parameter is the storage time of the fuel e.g. in view of spent fuel retrieval or in view of its final disposal. To extrapolate data obtainable from a laboratory-acceptable timescale to those expected after storage periods of interest have elapsed (amounting in the extreme case to geological ages) is a tough challenge. Emphasis is put on key aspects of fuel corrosion related to fuel properties at a given age and environmental conditions expected in the repository: e.g. the fuel activity (radiolysis effects), the effects of helium build-up and of groundwater composition. A wide range of techniques, from traditional leaching experiments to advanced electrochemistry, and of materials, including spent fuel with different compositions/burnups and analogues like the so-called alpha-doped UO 2 , are employed for these studies. The results confirm the safety of European underground repository concepts. (authors)

Theoretical insights into the minority carrier lifetime of doped Si—A computational study

Science.gov (United States)

Iyakutti, K.; Lavanya, R.; Rajeswarapalanichamy, R.; Mathan Kumar, E.; Kawazoe, Y.

2018-04-01

Using density functional theory, we have analyzed the ways and means of improving the minority carrier lifetime (MCL) by calculating the band structure dependent quantities contributing to the MCL. We have computationally modeled silicon doped with different elements like B, C, N, O, P, Ti, Fe, Ga, Ge, As, In, Sn, Sb, and Pt and looked at the effect of doping on MCL. In co-doping, the systems Si-B-Ga, Si-B-Ge, Si-B-2Ge, Si-B-Pt, Si-Ga-Ge, Si-Ga-2Ge, and Si-Ga-Pt are investigated. From our calculation, it is found that by doping and co-doping of Si with suitable elements having "s" and "p" electrons, there is a decrease in the recombination activity. The predicted effective minority carrier lifetime indicates the possibility of significant improvements. Based on the above studies, it is now maybe possible, with suitable choice of dopant and co-dopant material, to arrive at part of a standard production process for solar grade Si material.

Spent fuel performance in geologic repository environments

International Nuclear Information System (INIS)

Bradley, D.J.

1985-10-01

The performance assessment of the waste package is a current area of study in the United States program to develop a geologic repository for nuclear waste isolation. The waste package is presently envisioned as the waste form and its surrounding containers and possibly a packing material composed of crushed host rock or mixtures of that rock with clays. This waste package is tied to performance criteria set forth in recent legislation. It is the goal of the Civilian Radioactive Waste Management Program to obtain the necessary information on the waste package, in several geologic environments, to show that the waste package provides reasonable assurance of meeting established performance criteria. This paper discusses the United States program directed toward managing high-level radioactive waste, with emphasis on the current effort to define the behavior of irradiated spent fuel in repository groundwaters. Current studies are directed toward understanding the rate and nature (such as valence state, colloid form if any, solid phase controlling solubility) of radionuclide release from the spent fuel. Due to the strong interactive effect of radiation, thermal fields, and waste package components on this release, current spent fuel studies are being conducted primarily in the presence of waste package components over a wide range of potential environments

Spent-fuel-storage alternatives

Energy Technology Data Exchange (ETDEWEB)

1980-01-01

The Spent Fuel Storage Alternatives meeting was a technical forum in which 37 experts from 12 states discussed storage alternatives that are available or are under development. The subject matter was divided into the following five areas: techniques for increasing fuel storage density; dry storage of spent fuel; fuel characterization and conditioning; fuel storage operating experience; and storage and transport economics. Nineteen of the 21 papers which were presented at this meeting are included in this Proceedings. These have been abstracted and indexed. (ATT)

Development of the down-ender and the spent fuel rod cutting device

International Nuclear Information System (INIS)

Kim, S. H.; Yoon, Ji Sup; Kim, Young Hwan; Hoo, Jung Jae; Hong, Dong Hee; Kim, Do Woo

2000-07-01

It is necessary to disassemble the spent fuel assembly for the recycling of the PWR spent fuels. The spent fuel disassembling process includes transportation and handling of the spent fuel assembly, extraction and cutting of the spent fuel rods, and extraction of the spent fuel pellets(decladding). In this study, the downender of the spent fuel assembly and the spent fuel rod cutting device have been developed. The downender is used to change the posture of the spent fuel assembly from the vertical to the horizontal directions, prior to extracting the fuel rods. The concepts of the remote operation and maintenance has been introduced in the design of the downender. Also, the several design consideration has been given such as the reliable adaptation of the vertically accessing the assembly to the device, the minimization of the shock force when settling down the assembly, and the interface with the rod extraction device without intermittent operation. The spent fuel rod cutting device using a tube cutter is developed for cutting the fuel rods to the suitable size. In designing this device, the mechanical property of the spent fuel rod is examined such as the strength of the clad material and the optimal size of the rod for the extracting process. Also, several cutting methods, which are commercially available, are investigated and tested in terms of the durability, the deformation on the cutting surface of the rods, and the amount of the generated debris, and the fire risk. As like the downender, the design of this device accommodates the concepts of the remote operation and maintenance

Formulation study on immobilization of spent ion exchange resins in polymer cement

International Nuclear Information System (INIS)

Xia Lili; Lin Meiqiong; Bao Liangjin; Fan Xianhua

2006-01-01

The aim of this study is to develop a formulation of cement-solidified spent radioactive ion exchange resin form. The solidified form consists of a sort of composite cement, epoxide resin emulsion, and spent ion exchange resins. The composite cement is made up of quick-setting sulphoaluminate cement, silica powder, zeolite, and fly ash in the proportion 1:0.05:0.10:0.05. Sixteen combinations of composite cement, epoxide resin emulsion and mixed anion-cation exchange resins are selected according to a three-factors-four-levels normal design table with the compression strength as the evaluation criterion. The resulted formulation is as follows: the mass ratio of polymer emulsion to composite cement is 0.55:1, the loading of mixed anion-cation exchange resins is 0.3, and the anionic-to-cationic exchange resins ratio is 2:1. The polymer cement solidified forms were tested after 28 d curing for Cs + and Sr 2+ leaching rates, pH and conductivity of the leaching water, and radiation-resistant property in addition to their compressive strength. The measurement results indicate that the performance of thus prepared solidified forms can meet the requirements of the National Standard GB14569.1-93 for near earth's surface disposal of low radioactive waste. (authors)

Spent fuel storage requirements, 1988

International Nuclear Information System (INIS)

1988-10-01

Historical inventories of spent fuel and Department of Energy (DOE) estimates of future discharges from US commercial nuclear reactors are presented for the next 20 years, through the year 2007. The eventual needs for additional spent fuel storage capacity are estimated. These estimates are based on the maximum capacities within current and planned at-reactor facilities and on any planned transshipments of fuel to other reactors or facilities. Historical data through December 1987 and projected discharges through the end of reactor life are used in this analysis. The source data was supplied by the utilities to DOE through the 1988 RW-859 data survey and by DOE estimates of future nuclear capacity, generation, and spent fuel discharges. 12 refs., 3 figs., 28 tabs

Lifetime value in business process

Directory of Open Access Journals (Sweden)

Martin Souček

2011-01-01

Full Text Available The paper focuses on lifetime value assessment and its implementation and application in business processes. The lifetime value is closely connected to customer relationship management. The paper presents results of three consecutive researches devoted to issues of customer relationship management. The first two from 2008 and 2010 were conducted as quantitative ones; the one from 2009 had qualitative nature. The respondents were representatives of particular companies. The means for data collection was provided by ReLa system. We will focus on individual attributes of lifetime value of a customer, and relate them to approaches of authors mentioned in introduction. Based on the qualitative research data, the paper focuses on individual customer lifetime value parameters. These parameters include: the cost to the customer relationship acquisition and maintenance, profit generated from a particular customer, customer awareness value, the level of preparedness to adopt new products, the value of references and customer loyalty level. For each of these parameters, the paper provides specific recommendations. Moreover, it is possible to learn about the nature of these parameter assessments in the Czech environment.

Thermal model of spent fuel transport cask

International Nuclear Information System (INIS)

Ahmed, E.E.M.; Rahman, F.A.; Sultan, G.F.; Khalil, E.E.

1996-01-01

The investigation provides a theoretical model to represent the thermal behaviour of the spent fuel elements when transported in a dry shipping cask under normal transport conditions. The heat transfer process in the spent fuel elements and within the cask are modeled which include the radiant heat transfer within the cask and the heat transfer by thermal conduction within the spent fuel element. The model considers the net radiant method for radiant heat transfer process from the inner most heated element to the surrounding spent elements. The heat conduction through fuel interior, fuel-clad interface and on clad surface are also presented. (author) 6 figs., 9 refs

Models for Battery Reliability and Lifetime

Energy Technology Data Exchange (ETDEWEB)

Smith, K.; Wood, E.; Santhanagopalan, S.; Kim, G. H.; Neubauer, J.; Pesaran, A.

2014-03-01

Models describing battery degradation physics are needed to more accurately understand how battery usage and next-generation battery designs can be optimized for performance and lifetime. Such lifetime models may also reduce the cost of battery aging experiments and shorten the time required to validate battery lifetime. Models for chemical degradation and mechanical stress are reviewed. Experimental analysis of aging data from a commercial iron-phosphate lithium-ion (Li-ion) cell elucidates the relative importance of several mechanical stress-induced degradation mechanisms.