International Nuclear Information System (INIS)

The report presents the results of the study carried out to estimate the accident risk involved in the transport of spent fuel from Rajasthan Atomic Power Station near Kota to the fuel reprocessing plant at Tarapur. The technique of probabilistic safety analysis is used. The fuel considered is the Indian pressurised heavy water reactor fuel with a minimum cooling period of 485 days. The spent fuel is transported in a cuboidal, naturally-cooled shipping cask over a distance of 822 km by rail. The Indian rail accident statistics are used to estimate the basic rail accident frequency. The possible ways in which a release of radioactive material can occur from the spent fuel cask are identified by the fault tree analysis technique. The release sequences identified are classified into eight accident severity categories, and release ...

International Nuclear Information System (INIS)

To make a quantitative comparison of risks between the SNR 300 and a modern PWR (Biblis B), the consequences of an accident or the extent of damage of a release of radionuclides to the environment due to an accident are estimated by computer programs for accident consequence models. The accident analysis includes an analysis of events for Bethe-Tait accidents with failure of the outer containment. The FGSB release rates are compared with those of the Society for Reactor Safety (GRS). (HP).

Energy Technology Data Exchange (ETDEWEB)

To make a quantitative comparison of risks between the SNR-300 and a modern PWR (Biblis B), the consequences of an accident or the extent of damage of a release of radionuclides to the environment due to an accident are estimated by computer programs for accident consequence models. The accident analysis includes an analysis of events for Bethe-Tait accidents with failure of the outer containment. The FGSB release rates are compared with those of the Society for Reactor Safety (GRS).

International Nuclear Information System (INIS)

The understanding of fission product deposition in realistic steam generator conditions is needed for release estimates in PSA studies, and for the design of efficient accident management procedures. This is considered very important because primary-to-secondary leakages risk dominant sequences in many plants. Furthermore, the decay heat of the fission product deposits adds to the thermal load to the steam generator tubes also in other sequences, especially in case of cold leg leakages. This brings out the concern of induced steam generator tube ruptures in cases, where the steam generators are initially intact. The experimental data showed that the highest deposited fraction within the tubes were found in cases with lowest flow velocities. The minimum value of the deposited fraction was observed at intermediate flow velocities. With these relatively low Reynolds numbers, the results calculated with ...

International Nuclear Information System (INIS)

In the VEGA program on radionuclide release from irradiated fuel under severe accident conditions, 10 tests in total were performed at JAEA from 1999 to 2004 under inert and steam atmospheres including the highest pressure or temperature conditions. These tests showed the increase in release rate above 2,800 K or at the fuel liquefaction and the decrease in release rate under elevated pressure, which was a first observation in the world. The data on low-volatility radionuclide release, release from MOX fuel, effect of fuel oxidation, and eutectic reaction with cladding on release were obtained from the tests. The mechanism of pressure effect on release was examined and a new release model with pressure effect was proposed. In addition, the pressure effect on source term evaluation and effectiveness ...

Energy Technology Data Exchange (ETDEWEB)

The Nuclear Regulatory Commission (NRC) has sponsored several studies to identify and quantify, through the use of models, the potential health effects of accidental releases of radionuclides from nuclear power plants. The Reactor Safety Study provided the basis for most of the earlier estimates related to these health effects. Subsequent efforts by NRC-supported groups resulted in improved health effects models that were published in the report entitled {open_quotes}Health Effects Models for Nuclear Power Plant Consequence Analysis{close_quotes}, NUREG/CR-4214, 1985 and revised further in the 1989 report NUREG/CR-4214, Rev. 1, Part 2. The health effects models presented in the 1989 NUREG/CR-4214 report were developed for exposure to low-linear energy transfer (LET) (beta and gamma) radiation based on the best scientific information available at that time. Since the 1989 report was published, two addenda to that report have been prepared to (1) incorporate other ...

International Nuclear Information System (INIS)

Modelling the behaviour of fission product (FP) in a nuclear reactor coolant system (RCS) undergoing a hypothetical severe accident is an important step in the evaluation of radioactive release outside a nuclear power plant. This paper scrutinize Small Break LOCA sequence for WWER1000 reactor in order to investigate the possible paths for release of FP from fuel pallets to the reactor containment. Contemporaneous computer code for simulation of RCS will be use for the analysis. The results from analysis of fuel damage and release of FP trough the break of cold leg are present. (author)

International Nuclear Information System (INIS)

A semi-mechanistic model for calculating solid radionuclide release rates from bubbling pools of sodium was developed. The influence of particle spacial and size distributions on the decontamination of the releases was analysed and found significant. Decontamination factors are shown as a function of pool depth, bubbling characteristics and particle size distribution. The calculation of a decontamination factor for estimating the source term of large scale hypothetical core disruptive accidents is presented. The decontamination factor for a large scale accident was found to be two orders of magnitude greater than results obtained from small scale experiments conducted with uniform particle distributions. (orig.).

International Nuclear Information System (INIS)

Following the 1986 Chernobyl accident there was an understandable increase in public interest in nuclear accidents and emergency planning for them. It became clear that the broad nature, timing and scale of the radiological hazard presented by such accidents was, however, little understood. This Paper sets out in simple terms the basic features of the radiological hazard to persons in the vicinity of a nuclear power plant should a serious accident occur. The Paper starts by stressing the difference between faults -events that may occur relatively frequently - and accidents -unplanned releases of radioactivity that are by design extremely unlikely events. The Paper examines the significance of different exposure pathways and relates them to the protective measures (countermeasures) that may be taken. These countermeasures include sheltering, evacuation and the ...

International Nuclear Information System (INIS)

The potential public safety impacts from accidents in conceptual fusion power plants were investigated. Fusion was found to have some potential for accidents, as does any energy generating system. Functions of fusion power plants were identified that possess sufficient potential for an accidental release of toxic materials to the environment. An assessment was made of the impact of the potential accidents and recommendations are included for R and D that will allow incorporation of safety concerns in fusion power plant design. This work was based on a review of information available in conceptual design documents of fusion reactor systems.

International Nuclear Information System (INIS)

The volume contains reports on plant technology, on systems organisation with the aim to minimize the risk (human error), on the problem of seismic risk, on core-disruptive accidents and on accident consequence models with different release categories and a comparison of the potential damage incurred. Mr. Webb; one of the authors, attempts to disprove the objections to his two earliest SNR statements by experts of Karlsruhe Nuclear Research Centre. (AK).

Energy Technology Data Exchange (ETDEWEB)

Possible accident scenarios for a fusion reactor include breaches in the vacuum or cooling system. Intruding air or steam could react with structural or plasma facing materials, possibly mobilizing radioactive isotopes. Safety assessments must consider the early dose at the site boundary from the release of these activated materials. Previous calculations have indicated that cobalt isotopes dominate dose calculations for designs using stainless steel. Values used in these calculations, however, had been largely determined by the measurement limits of the chemical analysis methodology instead of measured releases. The purpose of the current study was to refine the analytical method to reduce the limit for detecting cobalt, and then test PCA steel in air and steam between 973 and 1473 K. Goals were to obtain more accurate measurements of cobalt mobilization in terms of g/m{sup 2}{center_dot}h and insight into the mobilization ...

Energy Technology Data Exchange (ETDEWEB)

The report contains an overall frame for transformation of knowledge and experience from risk analysis to emergency education. An accident model has been developed to describe the emergency situation. A key concept of this model is uncontrolled flow of energy (UFOE), essential elements are the state, location and movement of the energy (and mass). A UFOE can be considered as the driving force of an accident, e.g., an explosion, a fire, a release of heavy gases. As long as the energy is confined, i.e. the location and movement of the energy are under control, the situation is safe, but loss of confinement will create a hazardous situation that may develop into an accident. A domain model has been developed for representing accident and emergency scenarios occurring in society. The domain model uses three main categories: status, context and objectives. A domain is a group of ...

International Nuclear Information System (INIS)

An experimental technique is described which allows for parametric investigations of transient behavior of mobile core materials in a fuel bundle geometry. For the out-of-pile simulation of energy releases resulting from mild TOP- or LOF-accidents the exothermic reaction of an aluminium-oxide-thermite is used. Transient material relocation inside the test section is recorded by X-ray-cinematography. Results of some experiments recently performed close to conditions expected to be achieved during mild TOP-accidents are described in detail.

Energy Technology Data Exchange (ETDEWEB)

Molybdenum is an essential element for living organisms. Moreover its radionuclides may represent an incorporation risk for members of the public and/or radiation workers after a nuclear accident or a release of radioactive materials. However, only few reliable data on Mo biokinetics in humans were available. The results of recent tracer kinetic investigations with stable isotopes have shown several differences from the ICRP data with regard to the processes of intestinal absorption and of excretion. As a consequence, the dose coefficients calculated with a revised biokinetic model deviate from the ICRP estimates. By ingestion of {sup 99}Mo radionuclides with solid food, for example, the dose to the colon may be higher of a factor up to 1 order of magnitude, due to the fraction of non-absorbed material which traverses the gastro-intestinal tract. (orig.) [Deutsch] Molybdaen ist einerseits ein fuer Lebewesen essentielles ...

International Nuclear Information System (INIS)

We report on severe accident scenarios consequences evaluation in connection to the applied emergency countermeasures and use of the PC COSYMA code. We present some of the results for the reactor core melt accident assumed to happen at the 632 MWE PWR Krsko Nuclear Power Plant in Slovenia. The efficiency of several potential countermeasures in limiting the late health effects was studied. Regarding the source term, the majority of release parameters are as specified for category 2 in the German Risk Study. Site specific data were used. As the outside (meteorologic) conditions during the potential accident onset can be very different, the study limited to the deterministic runs, assuming the wind direction upstream the Sava river into the WNW direction, wind speed of 5 ms -1 and the C Pasquill stability category. The population distribution file was formed from the NEK-FSAR data for the 1991. (author)

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Following a postulated meltdown accident, the integrity of containment building structural material under attack by hot molten core debris and the safeguard of environment against radiological releases constitutes the final line of defense in PAHR safety assessment. Such assessment requires a good knowledge of UO/sub 2//interaction and penetration with different types of concrete. The present study focuses on the phenomena associated with core debris interaction/penetration with substrate basalt concrete.

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The RADionuclide Transport, Removal, And Dose (RADTRAD) code is designed for US Nuclear Regulatory Commission (USNRC) use to calculate the radiological consequences to the offsite population and to control room operators following a design-basis accident at Light Water Reactor (LWR) power plants. This code utilizes updated reactor accident source terms published in draft NUREG-1465, ``Accident Source Terms for Light-Water Nuclear Power Plants.`` The code will track the transport of radionuclides as they are released from the reactor pressure vessel, travel through the primary containment and other buildings, and are released to the environment. As the radioactive material is transported through the primary containment and other buildings, credit for several removal mechanisms may be taken including sprays, suppression pools, overlying pools, filters, and natural deposition. Simple ...

Energy Technology Data Exchange (ETDEWEB)

The SCDAP/RELAP5 code has been developed for best estimate transient simulation of light water reactor coolant systems during a severe accident. The code models the coupled behavior of the reactor coolant system, core, fission product released during a severe accident transient as well as large and small break loss of coolant accidents, operational transients such as anticipated transient without SCRAM, loss of off-site power, loss of feedwater, and loss of flow. A generic modeling approach is used that permits as much of a particular system to be modeled as necessary. Control system and secondary system components are included to permit modeling of plant controls, turbines, condensers, and secondary feedwater conditioning systems. This volume describes the organization and manner of the interface between severe accident models which are resident in the SCDAP portion of the code and ...

Science.gov (United States)

Accidents Accident Preparedness, Accident Prevention, Chemical Accidents, Radiation Accidents Characterization Contingency Plans National Contingency Plan (NCP), Oil Removal...

Science.gov (United States)

Accidents Accident Preparedness, Accident Prevention, Chemical Accidents, Radiation Accidents Characterization Contingency Plans National Contingency Plan (NCP), Oil Removal...

Science.gov (United States)

Accidents Accident Preparedness, Accident Prevention, Chemical Accidents, Radiation Accidents Characterization Contingency Plans National Contingency Plan (NCP), Oil Removal...

International Nuclear Information System (INIS)

Integrated Leakage Rate Test (ILRT) of containment system plays a very important role in safety of a Nuclear Power Plant. Containment system constitutes the last physical barrier to release of radioactivity from the core and is called upon to mitigate the consequences of not only accidents within the design basis, but also some of the highly unlikely severe accidents. Hence, leak tightness of containment becomes uttermost priority for the safety of plant personnel and public. The containment and associated ESFs are tested before the first criticality and there after periodically during service. The pre-operational integrated leakage rate is carried out at LOCA based design pressure, at periodic test pressure and at some intermediate pressure points to assess the leakage characteristics. This paper summarizes the various requirements and activities relevant to the ILRT of the Indian Pressurized Heavy Water Reactor (PHWR) ...

Energy Technology Data Exchange (ETDEWEB)

Several steam generator tube rupture accidents have occurred at plants in the past. In this paper the Computational Multi-Fluid Dynamics (CMFD) investigation of the horizontal steam generator thermal-hydraulics during the tube rupture accident is performed. A guillotine of a steam generator U-tube is assumed with choked flow from the primary to the secondary side of the steam generator. We have computed water and steam velocity fields, steam volume fraction distribution on the steam generator secondary (shell) side, as well as the swell level increase. The simulation results are a support to the safety analyses of the steam generator tube rupture accident. Numerical simulation is performed with the multidimensional multi-fluid modelling approach. The two-phase flow around steam generator tubes in the bundle is modelled by the porous media approach. Interfacial mass, momentum and energy transfer are ...

Energy Technology Data Exchange (ETDEWEB)

The factors influencing premixed burning and the importance of premixed burning on the exhaust emissions from a small high-speed direct-injection diesel engine were investigated. The characteristics of premixed and diffusion burning were examined using a single-zone heat-release analysis. The mass of fuel burned in premixed combustion was found to be linearly related to the product of engine speed and ignition-delay time and to be essentially independent of the total amount of fuel injected. Accordingly, the premixed-burned fraction increased with increasing engine speed, with decreasing fuel-air ratio and with retarding injection timing. The hydrocarbon emissions did not correlate well with the premixed-burned fraction. In contrast, the oxides of nitrogen emissions were found to increase with decreasing premixed-burned fraction, indicating that diffusion burning, and not premixed burning, is the ...

International Nuclear Information System (INIS)

A featfinding committee of the German Federal Parliament in July 1980 recommended to perform a ''risk-oriented study'' of the SNR-300, the German 300 MW fast breeder prototype reactor being under construction in Kalkar. The main aim of this study was to allow a comparative safety evaluation between the SNR-300 and a modern PWR, thus to prepare a basis for a political decision on the SNR-300. Methods and main results of the study are presented in this paper. In the first step of the risk analysis six groups of accidents have been identified which may initiate core destruction. These groups comprise all conceivable courses, potentially leading to core destruction. By reliability analyses, expected frequency of each group has been calculated. In the accident analysis potential failure modes of the reactor tank have been investigated. Core destruction may be accompanied by the release of significant amounts of mechanical ...

Energy Technology Data Exchange (ETDEWEB)

The Feedwater System supplies feedwater to the steam generator at the required pressure, temperature and flow rate during the plant start-up, normal power operation, shutdown. When the Feedwater System is inoperable or unavailable, the Auxiliary Feedwater System supplies emergency feedwater to the steam generator. If main steam line break occurs, the increase of feedwater flow rate of the faulted steam generator due to decrease of the pressure in the faulted steam generator results in adverse effects in aspect of overcooling the Reactor Coolant System and increased containment pressure/temperature. To optimize the containment mass/energy analysis, this paper evaluates the maximum feedwater and auxiliary feedwater flow rate delivered to the faulted steam generator at each stage of pressure decrease in the faulted steam generator after a main steam line break accident. Calculated Feedwater flows are applied to calculate mass and energy release ...

International Nuclear Information System (INIS)

Plasma surface interactions in tokamaks are known to create significant quantities of dust, which settles onto surfaces and accumulates in the vacuum vessel. In ITER, a loss of vacuum accident may result in the release of dust which will be radioactive and/or toxic, and provides increased surface area for chemical reactions or dust explosion. A new method of analysis has been developed for modeling dust resuspension and transport in loss of vacuum accidents. The aerosol dynamic equation is solved via the user defined scalar (UDS) capability in the commercial CFD code Fluent. Fluent solves up to 50 generic transport equations for user defined scalars, and allows customization of terms in these equations through user defined functions (UDF). This allows calculation of diffusion coefficients based on local flow properties, inclusion of body forces such as gravity and thermophoresis in the convection term, and user defined ...

International Nuclear Information System (INIS)

The program package COSYMA for assessing the radiological and economic consequences of nuclear accidents, developed with the support of the European Commission, was applied to investigate the health effects and risks from accidental releases of radioactive material from the Daya Bay nuclear power plant. Population distribution data in the range of 80 km around the site and hourly meteorological data for the year 1985 representative of accident consequence analysis were used. The results showed that early effects are more important at distances closer to the site, while the number of fatal cancers is closely related to the population density and the late effects are still important at distances larger than 50 km from the site. The mean annual expected values for early mortality and late mortality estimated for the population within a circle of 80 km around the Daya Bay nuclear power plant are 4.5x10"-"3 and 0.1 yr"-"1, ...

Energy Technology Data Exchange (ETDEWEB)

Norwegian authorities regard with some disquiet the possibility of a criticality accident in a ship propulsion reactor core at the Kola coast. Along this coast, in land storages, floating storages and in submarines taken out of service, the total number of spent fuel reactor cores amount to two hundred. The total Cs-137 radioactivity in spent ship propulsion reactor fuel at the Kola peninsula can be assessed to 600,000 TBq. A worst case release may amount to more than 5,000 TBq Cs-137, a quantity which under unfavourable conditions might cause serious contamination locally and even across the border to Norway.

International Nuclear Information System (INIS)

Since 1945, more than 1.8 x 10"2"1 Bq of artificial radionuclides have been released into the atmosphere. Approximately 2.04 x 10"1"8B, i.e. approx. 0.11%, are the result of accidents at nuclear industrial facilities. This percentage is causing increased interest among researchers. This is due to the fact that in the wake of accidental release radionuclides become distributed unevenly across the Earth's surface, and the associated exposures, fluctuating from background level to several grays, an induce both stochastic and deterministic effects in the irradiated population. A comparative analysis of the medical consequences of the twentieth century's most serious nuclear events, namely the authorized dumping of high level radioactive waste into the river Techa in 1950, the explosion of a storage tank containing long lived radioactive waste in the Southern Urals in 1957, the fire at Sellafield in 1957 and the ...

Energy Technology Data Exchange (ETDEWEB)

FLOWTRAN-TF is a new two-component, two-phase thermal-hydraulics code to capture the detailed assembly behavior associated with loss-of-coolant accident analyses in multichannel assemblies of the SRS reactors. The local interfacial area of the two-phase mixture is computed by summing the interfacial areas contributed by each of three flow regimes. For smooth flow regime transitions, the code uses an interpolation technique in terms of component void fraction for each basic flow regime.

International Nuclear Information System (INIS)

In this paper a comparison between severe accident calculations performed for a WWER 1000 with the ASTEC1.1v0 and MELCOR 1.8.5 computer codes for a small break LOCA (ID 60 mm) without intervention of hydro accumulators is presented. This investigation has been performed in the framework of the SARNET project under the EURATOM 6th framework program. Once the accident sequence scenario is specified, both codes (MELCORE and ASTEC) are able to determine the core and containment damaged states, to estimate the release of radionuclides from the fuel as well as from the primary circuit and containment. Theses results are used to estimate the maximum period of the time during which the personnel could still take particular decisions in order to mitigate such an accident. The aim of the performed analysis is to estimate the discrepancy between ASTEC and MELCORE 1.8.5 calculations. Such discrepancies will be ...

International Nuclear Information System (INIS)

Short communication.

Energy Technology Data Exchange (ETDEWEB)

This report presents a probabilistic safety assessment of radioactive doses as consequences from accident scenarios to complement the deterministic assessment presented in the Waste Isolation Pilot Plant (WIPP) Safety Analysis Report (SAR). The International Council of Radiation Protection (ICRP) recommends both assessments be conducted to ensure that ''an adequate level of safety has been achieved and that no major contributors to risk are overlooked'' (ICRP 1993). To that end, the probabilistic assessment for the WIPP accident scenarios addresses the wide range of assumptions, e.g. the range of values representing the radioactive source of an accident, that could possibly have been overlooked by the SAR. Routine releases of radionuclides from the WIPP repository to the environment during the waste emplacement operations are expected to be essentially zero. In ...

Energy Technology Data Exchange (ETDEWEB)

This paper investigates the phase change behavior of 65 mol% capric acid and 35 mol% lauric acid, calcium chloride hexahydrate, n-octadecane, n-hexadecane, and n-eicosane inside spherical enclosures to identify a suitable heat storage material. Analytical models are developed for solidification and melting of sphere with conduction, natural convection, and heat generation. Both the models are validated with previous experimental studies. Good agreement was found between the analytical predictions and experimental study and the deviations were lesser than 20%. Heat flux release at the wall, cumulative energy release to the external fluid, are revealed for the best PCM. The influence of the size of encapsulation, initial temperature of the PCM, the external fluid temperature on solidified and molten mass fraction, and the total phase change time are also investigated. (author)

Energy Technology Data Exchange (ETDEWEB)

During the recrystallization by solid-phase-expitaxial (SPE) growth of supersaturated silicon alloys, a high concentration of interstitials is trapped. These are released by subsequent heating causing a transient (greatly enhanced) diffusion of the substitutional dopant by an interstitialcy mechanism. The enhancement may be as much as five orders of magnitude over tracer values, and shows an activation energy of only 1.8 +/- 0.2 eV. Following the transient, the interstitials condense into loops, allowing an independent estimate to be made of their concentration. From these observations, it is proposed that during ion implantation, a fraction of the implanted dopants can acquire their natural valency, and retain it as the crystallization interface passes. For group V dopants this creates the trapped interstitials, giving transient enhanced diffusion when they are released by subsequent annealing. 12 references, 6 figures.

International Nuclear Information System (INIS)

No information on steam/water two-phase flow behavior in large diameter pipes (10 inch or larger) at elevated pressures is available in the open literature. However, there are many applications, in the nuclear, chemical and petroleum industries among others where two-phase flows in large diameter pipes at elevated pressures and temperatures are encountered routinely or under accident scenarios. Experimental data on steam-water two-phase flow in a large diameter (20 inch, 50.08 cm I.D.) vertical pipe at elevated pressures and temperatures (2.8 MPa/230 C--6.4 MPa/280 C) have been obtained. Void fraction, two-phase mass flux, phase and velocity distributions as well as pressure drop along the test pipe have been measured using the Ontario Hydro Technologies (OHT) Pump Test Loop. The void fraction distributions were found to be axially symmetric and nearly flat over a wide range of two-phase flow conditions. The two-phase flow ...

Energy Technology Data Exchange (ETDEWEB)

Sheltering, evacuation and distribution of stable iodine tablets are considered to be major early emergency actions aiming at diminishing the consequences after a release of radioactive materials from nuclear power plants into the air. Whether in real situations emergency managers will act accordingly is hard to predict. Uncertainties associated with these decisions are termed 'volitional' uncertainties. These uncertainties, however, cannot be assessed by expert judgements as they express the decision at stake in an emergency situation. Uncertainties on the times to implement countermeasures and on the times for the general population to respond to these measures can be assessed by experts, as they represent 'lack-of-knowledge' uncertainties. This paper describes the difference in approach of both types of uncertainties and shows the results of expert judgements on the latter type of uncertainties in early emergency actions. Ten ...

Energy Technology Data Exchange (ETDEWEB)

The processes of lung growth, injury, and repair are characterized by alterations in fibroblast synthesis and interstitial distribution of extracellular matrix components. Transforming growth factor beta (TGF-beta), which is postulated to play a role in modulating lung repair, alters the distribution of several matrix components such as collagen and fibronectin. We studied the effect of TGF-beta on the synthesis and distribution of the various glycosaminoglycans (GAGs) and whether these effects may explain its role in lung repair. Human diploid lung fibroblasts (IMR-90) were exposed to various concentrations of TGF-beta (0-5 nM) for variable periods of time (0-18 h). Newly synthesized GAGs were labeled with either (3H)glucosamine or (35S)sulfate. Individual GAGs were separated by size exclusion chromatography after serial enzymatic and chemical digestions and quantitated using scintillation counting. There was a dose-dependent increase in total GAG synthesis with maximal levels ...

International Nuclear Information System (INIS)

The release rate of a nuclide from a reactor or a radioactive waste disposal plant at the accident is not steady, but varies with time. The various parameters of a nuclide migration into environment vary also day after day, or with the seasons. In such cases, dynamic behavior of the nuclide in the environment must be taken into consideration. It is difficult for a mathematical model to involve all of mechanisms for the nuclide migration. The environment for evaluation of doses are usually divided into some of compartments in which a nuclide concentration is uniform. Time variations of the nuclide concentration in the compartment are described in simultaneous differential equations. The nuclide concentration can be solved as a time function, and the radiation doses, therefore, can be estimated as a time function. Generic analysis code for dynamic compartment model (GACOM) is developed for the nuclide migration and the evaluation of doses in ...

Energy Technology Data Exchange (ETDEWEB)

This file is devoted to the Chernobyl accident. It is divided in four parts. The first part concerns the accident itself and its technical management. The second part is relative to the radiation doses and the different contaminations. The third part reports the sanitary effects, the determinists ones and the stochastic ones. The fourth and last part relates the consequences for the other European countries with the case of France. Through the different parts a point is tackled with the measures taken after the accident by the other countries to manage an accident, the cooperation between the different countries and the groups of research and studies about the reactors safety, and also with the international medical cooperation, specially for the children, everything in relation with the Chernobyl accident. (N.C.)

Energy Technology Data Exchange (ETDEWEB)

As regards the environmental protection, the A.C.R.O. maintained in 2001 its programs of surveillance around the main western nuclear installations of France. The radioecological surveillance of the site of Cogema La-Hague for the dismantling of the former pipe of release in sea was one of the key points of this action environmental surveillance. The two accidents of atmospheric release in may and october 2001 at Cogema La Hague have shown the interest of an association as A.C.R.O.. It is thank to the measure, by our laboratory, of repercussions on environment of these incidents that it has been possible to bring to light a dysfunction of the measurement system of the gaseous effluents released by the facility operator. To improve the public information, A.C.R.O. concerns its main efforts on the development of the consumer technical information available on-line via its web site and in its regular ...

International Nuclear Information System (INIS)

The object of this paper is to identify the key elements that impact a radiation dose at EAB (Exclusion Area Boundary). This study is based on the AST (Alternative Source Terms) as defined in Regulatory Guide 1.183. The LOCA (Loss of Coolant Accident) and the LRA (Locked Rotor Accident) are selected as limiting cases. A sensitivity analysis of accidental behavior with respect to various parameters during LOCA and LRA at Kori Unit 1 is also undertaken for the following objectives: to determine the limiting parameters, to find the impact trend of the radiation dose, and to find the safety margin between AST and TID (Technical Information Document) methodologies. This work confirms that key parameters are particulate removal rate, decontamination factor, iodine chemical form, gap fraction, partitioning factor, and the impact of isotopes group. Comparing TID with AST, the radiation dose of TID is about 80% greater than that of ...

International Nuclear Information System (INIS)

This chapter provides an overview of the problem of response to a nuclear weapon accident, the fundamentals of response to an accident, and a summary of the NARP Manual. The manual provides a summary of procedural guidance, technical information, and DoD responsibilities, to assist DoD forces in preparing a response to a nuclear weapon accident.

International Nuclear Information System (INIS)

Short communication.

Energy Technology Data Exchange (ETDEWEB)

The Rb-Sr isotope systematics of bedrock, soil digests, and the cation exchange fraction of soils from a granitic glacial soil chronosequence in the Wind River Mountains, Wyoming, USA, were investigated. Six soil profiles ranging in age from 0.4 to {approximately}300 kyr were studied and revealed that the {sup 87}Sr/{sup 86}Sr ratio of exchangeable strontium in the B-horizons decreased from 0.7947 to 0.7114 with increasing soil age. Soil digests of the same samples showed much smaller variation in {sup 87}Sr/{sup 86}Sr from 0.7272 to 0.7103 and also generally decreased with increasing soil age. Elevation of the {sup 87}Sr/{sup 86}Sr ratios of Sr released by weathering over the soil digest and bedrock values results from the rapid weathering of biotite to form hydrobiotite and vermiculite in the younger soils. Biotite is estimated to weather at approximately eight times the rate of plagioclase (per gram of mineral) in the youngest soil profile ...

Energy Technology Data Exchange (ETDEWEB)

The release of {sup 222}Radon to the atmosphere is controlled by the rate of its gas transport through earthen materials. Of the many soil-related parameters, radon diffusion coefficient is the key parameter that characterizes this transport. We compared the radon diffusion coefficients measured at the laboratories for the UMTRA Project with simple empirical correlations developed by others. The empirical correlations predict the radon diffusion coefficient based on the fraction of moisture saturation and porosity. One of the more recent correlations agrees reasonably well with the measurements. In addition, by using a series of correlation curves, we studied the empirical relationships of the. radon diffusion coefficient with the saturated hydraulic conductivity, the fines content, and the moisture saturation in soil. The results reveal that a reliable determination of the long-term moisture and porosity is essential in the design of an ...

International Nuclear Information System (INIS)

Using the method of statistic planning of an experiment, the SrSO_4 desulfurization process has been studied in the case of reductive roasting of celestine with the use blast-furnace coke. The main factors that determine the rate of the SrSO_4 desulfurization are the roasting temperature and charge components dispersity. The desulfurization rate increases proportionally to the increase in the roasting temperature and dispersity of the reaction mixture components. To decrease the SrSO_4 desulfurization and the concentration of sulfur-containing components in gases released at rather a high celestine reduction rate, the roasting is recommended to proceed at the temperature of 1100 to 1150 deg, in this case it is necessary to limit the content of small (less than 3.2 mm) fractions of reagents.

International Nuclear Information System (INIS)

Accidents from three main practices: medical applications, industrial radiography and industrial irradiators are used to illustrate some common causes of accidents and the main lessons to be learned. A brief description of some of these accidents is given. Lessons learned from the described accidents are approached by subjects covering: safety culture, quality assurance, human factors, good engineering practice, defence in depth, security of sources, safety assessment and monitoring and verification compliance. (author)

International Nuclear Information System (INIS)

In VHTGR (Very High Temperature Gas-cooled Reactor), the radiation plays an important role in heat transfer through the cavity in RCCS (Reactor Cavity Cooling System). We performed the series of experiments to measure the emissivity using the infrared thermometer with wavelength range of 8#approx#14 #mu#m. As the first step, the transmittance of Zinc Selenide (ZnSe) window was measured to estimate the emissivity that can compensate the attenuation effect of window. The kind of gas with various concentrations in the cavity will be released during postulated accidents to the coolant type, so it is essential to estimate the effects of gas on the measurement of emissivity. In this manner we measured the emissivity with the air, the helium and the steam inside chamber. The results represent that the concentration of the air and the helium do not affect the emissivity significantly while the steam decreases the measured emissivity relatively. It ...

Energy Technology Data Exchange (ETDEWEB)

The increasing number of hazardous materials accidents in the United States has resulted in new federal regulations addressing the emergency response activities associated with chemical releases. A significant part of these new federal standards (29 CFR 1910.120 and 40 CFR Part 311) requires compliance with specific criteria by all personnel involved in a hazardous material emergency. This study investigated alternative lesson design models applicable to instruction for hazardous material emergencies. A specialized design checklist was created based on the work of Gagne, Briggs, and Wager (1988), Merrill (1987), and Clark (1989). This checklist was used in the development of lesson plan templates for the hazardous materials incident commander course. Qualitative data for establishing learning objectives was collected by conducting a needs assessment and a job analysis of the incident commander position. Incident commanders from 14 public and ...

Energy Technology Data Exchange (ETDEWEB)

The Institute of Energetic and Nuclear Research - IPEN is a research and development institution, located in a densely populated area, in the city of Sao Paulo. The nuclear fuel cycle was developed from the Yellow Cake to the enrichment and reconversion at IPEN. After this phase, all the technology was transferred to private enterprises and to the Brazilian Navy (CTM/SP). Some plants of the fuel cycle were at semi-industrial level, with a production over 20 kg/h. As a research institute, IPEN accomplished its function of the fuel cycle, developing and transferring technology. With the necessity of space for the implementation of new projects, the uranium hexafluoride (UF{sub 6}) production plant was chosen, since it had been idle for many years and presented potential leaking risks, which could cause environmental aggression and serious accidents. This plant decommission required accurate planning, as this work had not been carried out in Brazil before, for this ...

International Nuclear Information System (INIS)

Lappeenranta University of Technology (LTKK) and VTT Energy carried out a series of preliminary experiments in 1999 to study the behavior of noncondensable (NC) gases in VVER geometry. The experiments were run on the Parallel Channel Test Loop (PACTEL), which is a medium scale integral test facility designed to simulate thermal-hydraulic phenomena characteristic of VVER 440 type nuclear plants. The experiments aimed at studying the effect of noncondensable gases on system thermal-hydraulics and on heat transfer in a horizontal steam generator (HSG). The system behavior can be affected by hydrogen produced in the core in case of a severe accident, by nitrogen from hydro-accumulators (ACCU) released into the primary circuit in case of a loss-of-coolant accident (LOCA) and more generally by any noncondensable gas in all cases where cooling is ensured by natural circulation. This paper presents the measured results of the ...

International Nuclear Information System (INIS)

The Four years of the IMPACT, 'Integrated Modular Plant Analysis and Computing Technology' project Phase 1 have been completed. The verification study of Severe Accident Analysis Code SAMPSON prototype developed in Phase 1 was conducted in two steps. First, each analysis module was run independently and analysis results were compared and verified against separate-effect test data with good results. Test data are as follows: CORA-13 (FZK) for the Core Heat-up Module; VI-3 of HI/VI Test (ORNL) for the FP Release from Fuel Module; KROTOS-37 (JRC-ISPRA) for the Molten Core Relocation Module; Water Spread Test (UCSB) for the Debris Spreading Model and Benard's Melting Test for Natural Convection Model in the Debris Cooling Module; Hydrogen Burning Test (NUPEC) for the Ex-Vessel Thermal Hydraulics Module; PREMIX, PM10 (FZK) for the Steam Explosion Module; and SWISS-2 (SNL) for the Debris-Concrete Interaction Module. Second, with the Simulation ...

UK PubMed Central (United Kingdom)

Objective: To determine the experience of junior doctors cited as witnesses at fatal accident inquiries (FAIs). Design: Retrospective questionnaire study. Setting...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The report gives general principles of treatment and care of casualties caused by radiation accidents or nuclear explosions.

Energy Technology Data Exchange (ETDEWEB)

A series of meteorological and tracer experiments, was conducted during May and June 1984 over the 20-km wide /O/resund strait between Denmark and Sweden for the purpose of studying atmospheric dispersion processes over cold water and warm land surfaces and providing the data needed to evaluate meso-scale models in a coastal environment. In concert with these objectives the data from these experiments have been used as part of a continuing effort to evaluate the capability of the three-dimensional MATHEW/ADPIC (M/A) atmospheric dispersion models to simulate pollutant transport and diffusion characteristics of the atmospheric during a wide variety of meteorological conditions. Since previous studies have focused primarily on M/A model evaluations over rolling and complex terrain at inland sites, the /O/resund experiments provide a unique opportunity to evaluate the models in a coastal environment. The M/A models are used by the Atmospheric Release Advisory ...

Science.gov (United States)

The biological age (BA) of the majority of the liquidators of the consequences of the radiation accidents in the Navy and of the liquidators of the Chernobyl' APS accident exceeds the medium standard and the DBA (due BA). The index of the BA can be a characteristic of the influence of the social-hygienic factors on the health condition of the Special Risk Subunit--the liquidators of the consequences of the radiation accidents. It was established, that the radiation influence concerns to the factors dramatically increasing the BA and the rate of senescence of the liquidators of the consequences of the radiation accidents. PMID:21809627

International Nuclear Information System (INIS)

The consumption of food products obtained in areas subjected to radioactive contamination as a consequence of a radiation accident appears to be the most significant source of irradiation for the population. At the same time, this route can be regulated very effectively. The regularities of contamination of agricultural production, peculiar features of internal dose formation in the population and the effectiveness of countermeasures in agriculture have been analysed using the experience of two major accidents in the former USSR - in the South Urals (Kyshtym accident) in 1957, and at the Chernobyl NPP in 1986. (Author).

International Nuclear Information System (INIS)

Short communication.

Energy Technology Data Exchange (ETDEWEB)

With the exception of the 1945 Hiroshima and Nagasaki nuclear weapon explosions and the 1986 Tchernobyl reactor accident, most of the radiation accidents concerns the medical and the traditional industrial sectors. The seriousness of the accident is directly function of the absorbed dose. The paper, first, gives the definition of a radiologic accident with its specific criteria and pathological manifestations. Then, some famous historical accidents are reviewed from the discovery of X-rays to recent acute irradiations due to the careless manipulation of radiation sources. From this analysis, three main causes are put forward: the dysfunction of nuclear medicine apparatuses, the victims` lack of training and knowledge of the risks, and the non-identification or the loss of radiation sources. (J.S.). 1 photo.

Energy Technology Data Exchange (ETDEWEB)

The recent definition of a postulated thermal shock accident followed promptly by system repressurization, termed an overcooling or pressurized thermal shock accident, has set a large analysis and research effort into motion. The essential elements are concerned with defining the accident transients, evaluating the instrumentation and controls that cause the postulated accidents, and evaluating the metallurgical and structural mechanics aspects of the reactor vessel with respect to its failure potential. This paper poses the question faced by the Nuclear Regulatory Commission (NRC) for the vessel steel embrittlement, annealing, and surveillance dosimetry facets of this postulated accident and provides information on our plans for study of this problem as well as current status.

CERN Document Server

Suppose we would like to know all answers to a set of statistical queries C on a data set up to small error, but we can only access the data itself using statistical queries. A trivial solution is to exhaustively ask all queries in C. Can we do any better? + We show that the number of statistical queries necessary and sufficient for this task is---up to polynomial factors---equal to the agnostic learning complexity of C in Kearns' statistical query (SQ) model. This gives a complete answer to the question when running time is not a concern. + We then show that the problem can be solved efficiently (allowing arbitrary error on a small fraction of queries) whenever the answers to C can be described by a submodular function. This includes many natural concept classes, such as graph cuts and Boolean disjunctions and conjunctions. In doing so we also give a new learning algorithm for submodular functions that improves upon recent results in a different context. While ...

Energy Technology Data Exchange (ETDEWEB)

Biocatalytic Desulfurization (BDS) represents an alternative approach to the reduction of sulfur in fossil fuels. The objective is to use bacteria to selectively remove sulfur from petroleum and middle distillate fractions, without the concomitant release of carbon. Recently, bacteria have been developed which have the ability to desulfurize dibenzothiophene (DBT) and other organosulfur molecules. These bacteria are being developed for use in a biocatalyst-based desulfurization process. Analysis of preliminary conceptual engineering designs has shown that this process has the potential to complement conventional technology as a method to temper the sulfur levels in crude oil, or remove the recalcitrant sulfur in middle distillates to achieve the deep desulfurization mandated by State and Federal regulations. This paper describes the results of initial feasibility studies, sensitivity analyses and conceptual design work. Feasibility studies with ...

CERN Document Server

We analyze archived Chandra and XMM-Newton X-ray observations of 536 Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) quasars (QSOs) at 1.7 <= z <= 2.7 in order to characterize the relative UV and X-ray spectral properties of QSOs that do not have broad UV absorption lines (BALs). We constrain the fraction of X-ray weak, non-BAL QSOs and find that such objects are rare; for example, sources underluminous by a factor of 10 comprise $\\la$2% of optically-selected SDSS QSOs. X-ray luminosities vary with respect to UV emission by a factor of $\\la$2 over several years for most sources. UV continuum reddening and the presence of narrow-line absorbing systems are not strongly associated with X-ray weakness in our sample. X-ray brightness is significantly correlated with UV emission line properties, so that relatively X-ray weak, non-BAL QSOs generally have weaker, blueshifted CIV$\\lambda$1549 emission and broader CIII]$\\lambda$1909 lines. ...

UK PubMed Central (United Kingdom)

Two Brucella fractions, the murein-linked fraction PI and the murein-free fraction SF, behave as in vitro adjuvants for primary anti-sheep erythrocyte responses: added to Mishell and Dutton-type cultures...Full Text Available

International Nuclear Information System (INIS)

This multinational, multi-phase spent fuel sabotage test program is quantifying the aerosol particles produced when the products of a high energy density device (HEDD) interact with and explosively particulate test rodlets that contain pellets of either surrogate materials or actual spent fuel. This program has been underway for several years. This program provides data that are relevant to some sabotage scenarios in relation to spent fuel transport and storage casks, and associated risk assessments. The program also provides significant technical and political benefits in international cooperation. We are quantifying the Spent Fuel Ratio (SFR), the ratio of the aerosol particles released from HEDD-impacted actual spent fuel to the aerosol particles produced from surrogate materials, measured under closely matched test conditions, in a contained test chamber. In addition, we are measuring the amounts, nuclide content, size distribution of the ...

International Nuclear Information System (INIS)

This report describes the development of solidification systems for sodium nitrate waste. Sodium nitrate waste was solidified in the polymers polyethylene, polyester-styrene (PES), and water-extendible polyester-styrene (WEP). Evaluations were made of the properties of waste forms containing various amounts of sodium nitrate by leaching immersion in water, measuring compressive strengths and by the EPA Extraction Procedure. Results of the leaching test are presented as cumulative fraction leached (CFL), incremental leaching rate, and average leaching indices (LI). For waste forms containing 30 to 70 wt% sodium nitrate, the CFL ranged from 9.0 x 10"-"3 to 7.3 x 10"-"1 and the LI from 11 to 7.8. After ninety days immersion in water, the compressive strengths ranged from 720 psi to 2550 psi. The nitrate releases from these samples using the EPA Extraction Procedure were below 500 ppM. The nitrate releases from PES waste forms ...

International Nuclear Information System (INIS)

Uniform and transparent thin films of Zn_1_-_xCo_xO (0 #=# 0.035, CoO (cubic) was detected as the secondary phase. Influence of Co addition on the volume fraction of grain boundaries has been interpreted. Increase in Co content in the range 0 #<=# x #<=# 0.10 led to quenching of near-band edge and blue emissions, decrease in band gap energy (E_g) from 3.36 eV to 3.26 eV, decrease in film thickness and refractive index and an increase in extinction coefficient of Zn_1_-_xCo_xO thin films. The change in nature of stress from compressive to tensile with lower to higher doping of Co is corroborative with the angular peak shift of (002) plane of ZnO lattice. An overall increase in microhardness of Zn_1_-_xCo_xO thin films up to x = 0.05 is attributed to change in microstructure and evolution of secondary phase and as the secondary phase separates out the overall stress is released leading to lowering of hardness after this concentration. ...

Energy Technology Data Exchange (ETDEWEB)

Severe accident analysis has been performed for the Wolsung nuclear power= plants in Korea to investigate severe accident phenomena of CANDU-600 reactors as a part of Level II PSA study. The accident sequence analyzed in this paper is loss of active heat sinks (LOAH) which is caused by loss of off-site power, diesel generators, and DC power. ISAAC (Integrated Severe Accident Analysis Code) computer code developed by KAERI (Korea Atomic Energy Research Institute) was used in this analysis. This paper describes the important thermal-hydraulics and source term behaviors in the primary system and inside containment, and the failure mechanisms of calandria vessel and containment. In addition, some insights for accident management program (AMP) are also given. (Author) 5 refs., 1 tab., 12 figs.

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: A porous media solution PORFLO has been developed for the 3-dimensional two-phase flow by describing the process facility in Cartesian or cylindrical coordinates. The local porosity fraction is applied for distinguishing the fluid filled volumes from the solid structures. The solid structure contribute the two-phase flow through the wall friction, flow area and heat transfer. Optionally the solid structure may contain primary liquid of steam generators, steam in the higher temperature and pressure to be condensed or electrical heating power. By using these optional boundary conditions three different process facilities have been analysed. The thermohydraulic solution based on 5-equation approach, where the conservation equations are solved for the liquid and gas (vapour) mass, mixture momentum (giving the velocity only for the mixture), liquid and gas energy, is described shortly. In addition to that the principles modelling ...

International Nuclear Information System (INIS)

The IAEA attaches great importance to the dissemination of information that can assist Member States with the development, implementation, maintenance and continuous improvement of systems, programmes and activities that support the nuclear fuel cycle and nuclear applications, including management of the legacy of past practices and accidents. In this connection, the IAEA has initiated a comprehensive programme of work covering all aspects of environmental remediation: - Technical and non-technical factors, including costs, that influence environmental remediation strategies and pertinent decision making; - Site characterization techniques and strategies; - Assessment of remediation technologies; - Techniques and strategies for post-remediation compliance monitoring; - Special issues such as the remediation of sites with dispersed radioactive contamination or mixed contamination by hazardous and radioactive substances. Experience in Member States has shown that ...

International Nuclear Information System (INIS)

This paper deals with the calculations of 3D nuclear heat generation profile in the charcoal filter and subsequently the commencement time of Primary Containment Cleanup (PCC) system of 540MWe Pressurized Heavy Water Reactor (PHWR). Fuel failure is predicted due to overheating of the fuel under loss of Coolant Accident (LOCA) without Emergency Core Cooling System (LOCA without ECCS). Subsequently fission product gasses along with water vapours are released to Reactor Building (RB) atmosphere. Plate-out and water trapping mechanism stabilizes the concentration of significant fission products i.e. radioiodines in about 4 hours before being circulated through charcoal filters of Containment Cleanup system. After cleaning up the RB atmosphere, it is discharged to outside atmosphere through stack. The isotopes of radioiodine emit beta and gamma radiations. Gamma radiations are partly stopped within the charcoal and heat is generated. The part of ...

International Nuclear Information System (INIS)

During the last years one focus of German PWR safety analysis was boron dilution events with the potential of reactivity transients. Coolant with a low boron concentration could be collected in localized areas of the reactor coolant system e.g. by separation of borated reactor coolant into highly concentrated and diluted fractions (inherent dilution) which can occur during reflux- condenser heat transfer after a small break loss of coolant accident with a limited availability of the emergency core cooling systems. The TUeV NORD SysTec was charged by German supervisory authorities with the assessment of the safety analyses of boron dilution events presented by the utilities. These analyses are based on the simulation of boron dilution and transport processes in conjunction with a number of dedicated experiments. The analyses shall demonstrate that boron dilution events cannot lead to recriticality of the core. Hence the boron concentration at ...

UK PubMed Central (United Kingdom)

A screening questionnaire designed to take an alcohol history was used on 996 patients attending the London Hospital Accident and Emergency Department. Questions concerned with 'binge' drinking detected...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The chapter presents the nuclear energy development in 20th century and the most important radiation accidents happened from the point of view of technological risk and high impact consequences: Three Mile Island and Chernobyl.

Energy Technology Data Exchange (ETDEWEB)

{sup 14}C is a is a long-lived beta-emitting nuclide (T{sub 1/2} = 5730 years) produced naturally in the upper atmosphere as a result of reactions between neutrons and stable {sup 14}N({sup 14}N(n,p){sup 14}C). Although in a lesser extent, nuclear power plants produce {sup 14}C as well during their routine operation. Since it is converted in {sup 14}CO{sub 2} and mixed throughout the atmosphere, it is incorporated into plant tissues, via photosynthesis process, and hence in food chain. Because of the biological importance of {sup 14}C and long half-life, it is of interest to quantify the amounts released by nuclear industry. The Brazilian nuclear central named Nuclear Central Admiral Alvaro Alberto (CNAAA) has two nuclear reactors of PWR type in operation, Angra I (657 MWe) and Angra II (1350 MWe), and one under construction, Angra III (1309 MWe PWR). The aim of this study was to determine the strength of the sources and the {sup 14}C content in the environment ...

Science.gov (United States)

A post-accident-heat-removal structural effects analysis for the steel liner in the FFTF concrete containment structure is presented. (JWR)

Energy Technology Data Exchange (ETDEWEB)

This report draws an account of the consequences of Chernobyl accident 14 years after the disaster. It is made up of 8 chapters whose titles are: (1) Some figures about Chernobyl accident, (2) Chernobyl nuclear power plant, (3)Sanitary consequences of Chernobyl accident, (4) The management of contaminated lands, (5) The impact in France of Chernobyl fallout, (6) International cooperation, (7) More information about Chernobyl and (8) Glossary.

UK PubMed Central (United Kingdom)

This study investigated the feasibility of a slow-release inoculation approach as a bioaugmentation strategy for the degradation of lindane (γ-hexachlorocyclohexane [γ-HCH]). Slow-release...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

DOE installations possessing sufficient quantities of fissile material to potentially constitute a critical mass, such that the excessive exposure of personnel to radiation from a nuclear accident is possible, are required to provide nuclear accident dosimetry services. This document describes the personal nuclear accident dosimeter (PNAD) used by SNL and prescribes methodologies to initially screen, and to process PNAD results. In addition, this report describes PNAD dosimetry results obtained during the Nuclear Accident Dosimeter Intercomparison Study (NAD23), held during 12-16 June 1995, at Los Alamos National Laboratories. Biases for reported neutron doses ranged from -6% to +36% with an average bias of +12%.

International Nuclear Information System (INIS)

Probabilistic risk assessment is a technique used to systematically analyze complex technical systems, such as nuclear waste management facilities, in order to identify and measure their public health, environmental, and economic risks. Probabilistic techniques have been utilized at the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico, to evaluate the probability of a catastrophic waste hoist accident. A probability model was developed to represent the hoisting system, and fault trees were constructed to identify potential sequences of events that could result in a hoist accident. Quantification of the fault trees using statistics compiled by the Mine Safety and Health Administration (MSHA) indicated that the annual probability of a catastrophic hoist accident at WIPP is less than one in 60 million. This result allowed classification of a catastrophic hoist accident as ''not credible'' at ...

Energy Technology Data Exchange (ETDEWEB)

The ingestion pathway consequences following an accidental tritium release from the Savannah River Site Tritium Facilities are evaluated.

International Nuclear Information System (INIS)

Biosynthesis of hemoglobin and some of its electrophoretic fractions in red cells of peripheral blood and spleen of irradiated (650 R) rats has been studied. Hemoglobin synthesis is found to be most drastically inhibited in the first and second fractions on the first and eighth days after irradiation and in the fifth and sixth fractions on the eighth day (less expressed). The synthesis is restored on the twelfth day, the process under study proceeding more slowly in the above-mentioned fractions than in others. In the course of radiation sickness, the biosynthesis of certain hemoglobin fractions varies differently in the hemoglobin-synthesizing cells of peripheral blood than in the cells of spleenic erythroid series.

Energy Technology Data Exchange (ETDEWEB)

The NUclear Power Engineering Corporation (NUPEC) has developed IMPACT-SAMPSON code to analyze integral behavior of light water nuclear power plants under severe accident conditions. IMPACT-SAMPSON's distinguishing features include interconnected hierarchical modules and mechanistic models covering a wide spectrum of scenarios ranging from normal operation to severe accident events, and high-speed simulation on parallel processing computers. The integral plant behaviors of typical PWR and BWR under severe accident conditions have been analyzed with the IMPACT-SAMPSON code. The PWR plant analyzed was the three-loop, steel-dry containment type with 2,440 MWt. The AE accident scenario was supposed, that is, LOCA by 6-inch hot leg failure followed by accumulated water injection, but no ECCS and containment spray activation. The BWR plant analyzed was the 3,293 MWt BWR-5, Mark-II containment type. ...

International Nuclear Information System (INIS)

This paper describes the activities for improving the Probabilistic Safety Assessment (PSA) quality in the human reliability analysis (HRA) of the pre-accident human errors for the Korea Standard Nuclear Power Plant (KSNP). We evaluate the HRA results of the PSA for the KSNP and identify the items to be improved using the ASME PRA Standard. Evaluation results show that the ratio of items to be improved for pre-accident human errors is relatively high when compared with the ratio of those for post-accident human errors. They also show that more than 50% of the items to be improved for pre-accident human errors are related to the identification and screening analysis for them. In this paper, we develop the modeling guidelines for pre-accident human errors and apply them to the auxiliary feedwater system of the KSNP. Application results show that more than 50% of the items to be ...

Energy Technology Data Exchange (ETDEWEB)

Chemical looping combustion is a novel technology that can be used to meet the demand on energy production without CO{sub 2} emission. To improve CO{sub 2} capture efficiency in the process of chemical looping combustion of coal, a prototype configuration for chemical looping combustion of coal is made in this study. It comprises a fast fluidized bed as an air reactor, a cyclone, a spout-fluid bed as a fuel reactor and a loop-seal. The loop-seal connects the spout-fluid bed with the fast fluidized bed and is fluidized by steam to prevent the contamination of the flue gas between the two reactors. The performance of chemical looping combustion of coal is experimentally investigated with a NiO/Al{sub 2}O{sub 3} oxygen carrier in a 1 kW{sub th} prototype. The experimental results show that the configuration can minimize the amount of residual char entering into the air reactor from the fuel reactor with the external circulation of oxygen carrier particles giving up to 95% of CO{sub 2} ...

International Nuclear Information System (INIS)

Korea Atomic Energy Research Institute, using the ANS low power and shutdown (LPSD) probabilistic risk assessment (PRA) Standard, evaluated the LPSD PSA model of the KSNP, Yonggwang Units 5 and 6, and identified the items to be improved. The evaluation results of human reliability analysis (HRA) of the post-accident human errors in the LPSD PSA model for the KSNP showed that 10 items among 19 items of supporting requirements for those in the ANS PRA Standard were identified as them to be improved. Thus, we newly carried out a HRA for post-accident human errors in the LPSD PSA model for the KSNP. Following tasks are the improvements in the HRA of post-accident human errors of the LPSD PSA model for the KSNP compared with the previous one: Interviews with operators in the interpretation of the procedure, modeling of operator actions, and the quantification results of human errors, site visit. Applications of limiting value to ...

Wastenet

... The larvae's only hope for survival is if the antibiotic tetracycline is present -because it mops up the enzyme. The developers hope male GM mosquitoes will compete with normal males for females so that repeated releases cut numbers of A. aegypti in dengue-prone areas. The mosquitoes will be released in the inland districts of Bentong in the state of Pahang, and Alor Gajah and Melaka in the state of Malacca, according to the National Biosafety Board. Each location will have two release phases: the first at a site ...

Energy Technology Data Exchange (ETDEWEB)

This document presents the results of a review of publicly available information on energy use in health care facilities. The information contained in this document and in the sources cited herein provides the background and context for efforts to reduce energy use and costs in health care. Recognizing the breadth and diversity of relevant information, the author acknowledges that the report is likely not comprehensive. It is intended only to present a broad picture of what is currently known about health care energy use. This review was conducted as part of a 'High Performance Health Care Buildings' research study funded by the California Energy Commission. The study was motivated by the recognition that health care facilities collectively account for a substantial fraction of total commercial building energy use, due in large part to the very high energy intensity of hospitals and other inpatient care facilities. The goal of the study was to ...

International Nuclear Information System (INIS)

The present study was undertaken to determine the involvement of calcium-protein kinase C pathway in the mechanism of action of Escherichia coli heat stable enterotoxin (STa) apart from STa-induced activation of guanylate cyclase in human colonic carcinoma cell line COLO-205, which was used as a model cultured cell line to study the mechanism of action of E. coli STa. In response to E. coli STa, protein kinase C (PKC) activity was increased in a time-dependent manner with its physical translocation from cytosol to membrane. Inhibition of the PKC activity in membrane fraction and inhibition of its physical translocation in response to IP_3-mediated calcium release inhibitor dantrolene suggested the involvement of intracellular store depletion in the regulation of PKC activity. Among different PKC isoforms, predominant involvement of calcium-dependent protein kinase C (PKC#alpha#) was specified using isotype-specific pseudosubstrate, which showed ...

Energy Technology Data Exchange (ETDEWEB)

Despite extensive clinical use of thallium-201 (/sup 201/Tl) for myocardial imaging, the effect of ischemia on myocardial accumulation and release of /sup 201/Tl independent of flow has not been fully defined. Therefore, myocardial accumulation of /sup 201/Tl in response to ischemic-like myocardial injury was assessed in vitro using the cultured fetal mouse heart preparation. Cultured fetal mouse hearts (n . 311) were subjected to injury simulating ischemia by deprivation of oxygen and oxidizable substrates for periods ranging from 15 minutes to 10 hours. The extent of irreversible injury was determined by the percentage of lactic dehydrogenase (LDH) lost from the hearts to the culture medium during recovery from injury. Injury was essentially reversible at 1 hour of insult. The fraction of /sup 201/Tl content in injured compared with control hearts was not significantly lower after 1 hour of insult. By 3 hours of insult, irreversible injury as ...

International Nuclear Information System (INIS)

Metal waste generated from domestic nuclear operation for defense and commercial application has led to a growing stockpile of radioactively contaminated scrap metal, much of which is stainless steel. A significant fraction of this material cannot be efficiently surface decontaminated. The burial of this material would be wasteful and expensive, since long term monitoring would be necessary in order to minimize environmental risk. Much of this waste consists of bulky equipment. In many case, this equipment contains valuable material that may be recycled. The piece of equipment considered frequently also has complex geometries, making extremely difficult, time-consuming and expensive to determine the exact location and level of radioactivity on the internal surfaces. After melting, however, the radioactivity may be precisely determined from samples of each ingot. Moreover, an ingot may be released for restricted or unrestricted reuse, or stored ...

International Nuclear Information System (INIS)

Full text of publication follows: The TUV NORD e.V. is an independent Technical Support Organisation (TSO) performing safety assessments in almost every field of technology. In nuclear safety the TUV can look back on more than 40 years of experience. In the last years in Germany PWR safety analyses were focussed on boron dilution events with the potential of reactivity transients. The possibility of coolant with a low boron concentration collected in localized areas of the reactor coolant system (RCS) can be caused by injection of coolant with less boron content from interfacing systems (external dilution) as well as separation of borated reactor coolant into highly concentrated and diluted fractions (inherent dilution). Inherent dilution can e.g. occur after reflux-condenser heat transfer after a small break loss of coolant accident (SBLOCA) with a limited operability of the emergency core cooling (ECC) systems. The TUV Nord e.V. was charged ...

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

Short communication.

KoreaScience (Korea)

Full Text Available

British Library Electronic Table of Contents (United Kingdom)

This is a report of extraction and identification of 1-O-alkyl glycerol present in the dried leaves of Bauhinia scandens. Fifty percent aqueous ethanolic extract of the plant at room temperature was fractionated over petroleum ether and diethyl ether. The diethyl ether soluble fraction showed positive bioactivity in Brine Shrimp bioassay. Isolation and purification of the active principle was subsequently done from diethyl ether fraction. The diethyl ether fraction was separated into acidic and neutral part. The acid free fraction was screened to be positive in Brine Shrimp bioassay. The NMR spectra (in CDCl3) indicated the probability of its lipoidal nature. The total lipid fraction was resolved into neutral, glyco, and phospho-lipids by column chromatography. Only the neutral fraction sh...

International Nuclear Information System (INIS)

A ground-breaking study was recently completed as part of the Seabrook Level 2 PRA update. This study updates the post-core damage phenomena to be consistent with the most recent information and includes accident management activities that should be modeled in the Level 2 PRA. Overall, the result is a Level 2 PRA that fully meets the requirements of the ASME PRA Standard with respect to modeling accident management in the LERF assessment and NRC requirements in Regulatory Guide 1.174 for considering late containment failures. This technical paper deals only with the incorporation of operator actions into the Level 2 PRA based on a comprehensive study of the Seabrook Station accident response procedures and guidance. The paper describes the process used to identify the key operator actions that can influence the Level 2 PRA results and the development of success criteria for these key operator actions. This addresses a key ...

International Nuclear Information System (INIS)

The Food Safety and Inspection Service (FSIS) of the United States Department of Agriculture (USDA) inspects domestic and imported meat and poultry food products to assure the public that they are safe, wholesome, not economically adulterated and properly labeled. The Service also monitors the activities of meat and poultry plants and related activities in allied industries, and establishes standards and approves labels for meat and poultry products. As part of its responsibility, shortly after the Chernobyl accident occurred, FSIS developed a plan to assess this accident's impact on domestically produced and imported meat and poultry

International Nuclear Information System (INIS)

The authors suggested a conceptual model of automatic processing the data on radioactive environment contamination (REC) after the accidents at the plants with nuclear fuel cycle. The possibilities of mathematic methods of processing the data on REC in automatic-control systems of radiation situation. It is stated that the following 2 methods most of all satisfy the existing requirements: linear interpolation on the locally homogenous fields and successive parametric adaptation. As an example there are demonstrated the results of estimation of the actual radiation situation in the region of accident at Siberian Chemical Plant (town Tomsk-7) in April, 1993. 6 refs.; 2 figs.

International Nuclear Information System (INIS)

Russian 2004 p. 50-51 Russian Federation Kalyakin, SG Kapinos,

International Nuclear Information System (INIS)

In the revised GCFR Safety Program Plan a quantitative risk limit line has been adopted to establish requirements for the safety related functions and systems. The risk limit line is derived from an interpretation of NRC established licensing requirements, including those for LMFBR's. Multiple barriers to the progression of accident sequences are defined in the form of six Lines of Protection (LOPs). LOPs-1 to 3 are dedicated to accident prevention and represent the normal operating systems, the dedicated safety systems and the inherent design features, respectively. LOPs-4 to 6 are dedicated to the mitigation of core melt accident consequences and include in-vessel accident containment, secondary containment integrity and radiological attenuation, respectively. Cumulative frequency limits and consequence limits are established for each LOP. Design features associated with each LOP are described and the ...

Science.gov (United States)

Feb 6, 2003 ... Director, Plans and Programs, Headquarters Air Force Materiel Command, .... Commander of the Joint Task Force Southwest Asia at Prince ...

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our exploration of space, in a manner with improved safety. ... a new Space Transportation System. ... Columbia launches as STS-107 on January 16, 2003. ...

CERN Document Server

This contribution deals with identification of fractional-order dynamical systems. System identification, which refers to estimation of process parameters, is a necessity in control theory. Real processes are usually of fractional order as opposed to the ideal integral order models. A simple and elegant scheme of estimating the parameters for such a fractional order process is proposed. This method employs fractional calculus theory to find equations relating the parameters that are to be estimated, and then estimates the process parameters after solving the simultaneous equations. The said simultaneous equations are generated and updated using particle swarm optimization (PSO) technique, the fitness function being the sum of squared deviations from the actual set of observations. The data used for the calculations are intentionally corrupted to simulate real-life conditions. Results show that the ...

Energy Technology Data Exchange (ETDEWEB)

The risk perception of the public consists of two components: the objectively factual component and the subjectively irrational component. The two strategies adopted by the German gas supply industry are the internal and the external communication strategy. Concepts and measures of accident precaution, registration and analysis of accident data (installation and operating errors, defects on flue systems, pipelines and valves, subsequent installation of gas appliances) are discussed. (R.P.)

International Nuclear Information System (INIS)

Requirements and guidance are provided for a quality assurance program for the design of nuclear fuel reprocessing facilities involving structures, systems and components whose satisfactory performance is required to prevent accidents that could cause undue risk to the health and safety of the public, or to mitigate the consequences of such accidents if they were to occur. The standard is to be used in conjunction with ANSI N46.2.

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The management procedure of a large PRISE (Primary-to-Secondary) leakage accident at Loviisa nuclear power plant taking into account the plant modifications which are expected to be realized during 1995-96 is described. The management procedure has been validated by performing thermal hydraulic analyses with the computer code RELAP5/MOD3 and the results from these analyses are also shortly discussed. (4 refs., 6 figs., 1 tab.).

UK PubMed Central (United Kingdom)

We report for the first time a case of a 54 years old man with a fatal motorcycle accident due to an external bleeding compression of left internal mammary artery graft to the left anterior descending...Full Text Available

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The objectives of this project to interface the site-specific real-time radiological dose assessment system FADAS(Following Accident Dose Assessment System) to CARE. In this study, the results of the field tracer experiments conducted on the Younggwang site have been analysed. And the experimental procedure on Ulchin site has been introduced. The environmental characteristics on Ulchin and Wolsung has been investigated.

Energy Technology Data Exchange (ETDEWEB)

This study follows previous experimental work showing that the shrinking-core model applies to the pyrolysis (i.e., heating in the absence of oxygen) of particles (diam.{approx}14 mm) of a bituminous coal or a lignite in a fluidized bed at 700-950 {sup o}C. These experimental facts are in accord with the production of volatile matter being endothermic and not thermoneutral, as often assumed. Also, the rate at which volatile matter is produced in the presence of oxygen (i.e., devolatilization) or in its absence (pyrolysis) is demonstrated here to be controlled not at all by mass transfer, but by heat conduction to a moving reaction front inside a coal particle, provided its diameter exceeds {approx}3 mm. The resulting steady-state model of devolatilization indicates that six dimensionless groups are required to describe the rate of(I)coal->char+volatile matter for a nonfragmenting and nonswelling coal. This reaction occurs for a total time of c{sub 1}r{sub 0}+c{sub 2}r{sub 0}{sup ...

International Nuclear Information System (INIS)

Traditionally, probabilistic risk analyses [PRA] of severe accidents in nuclear power plants have limited themselves to consideration of the set of initiating events occurring during full power operation. However, some analyses of accident initiators during low power, shutdown, and other modes of plant operation other than full power have been performed. These studies as well as the Chernobyl accident and recent operating experience at U.S. pressurized water reactors suggested that risks during low power and shutdown could be significant. As such, the analysis of the frequencies, consequences, and risks of these accidents was identified as one task in the Nuclear Regulatory Commission staff's study of the implications of the Chernobyl accident to U.S. commercial nuclear power plants. The surry PRA project is an ongoing high priority effort at BNL [Brookhaven National Laboratory] ...

UK PubMed Central (United Kingdom)

Alkylphenols are widely used as plastic additives and surfactants. We report the identification of an alkylphenol, nonylphenol, as an estrogenic substance released from plastic centrifuge tubes. This...Full Text Available

UK PubMed Central (United Kingdom)

Secondary caries and restoration fracture remain the two most common problems in restorative dentistry. Release of fluoride ions (F) could be a substantial benefit because F could enrich neighboring...Full Text Available

UK PubMed Central (United Kingdom)

ObjectiveThe primary objective of this study was to assess whether pentagastrin-induced panic symptoms are associated with release of free fatty acids (FFAs) in a manner that could...Full Text Available

UK PubMed Central (United Kingdom)

The effects of gonadotrophin releasing hormone (GnRH) on the reproductive performance of dairy cows with retained placenta were studied. Three hundred and seventy-eight cows diagnosed as having retained...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundAntibodies against gonadotropin-releasing hormone (GnRH) and gastrointestinal dysmotility have been found after treatment with GnRH analogues. The aim of this study was...Full Text Available

UK PubMed Central (United Kingdom)

T-type calcium channels are responsible for generating low-threshold spikes that facilitate burst firing and neurotransmitter release in neurons. GnRH neurons exhibit burst firing, but the underlying...Full Text Available

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... sensitive and classified US Government information, a notable recent example being the unlawful release of classified US documents by WikiLeaks ...

KoreaScience (Korea)

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... Release/Receipt Document I&S Interchangeability and Substitutability ISSP Inter-Service Supply Support Procedures JANAP J

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... Deepwater Horizon leak in the Gulf of Mexico, the Haitian earthquake and subsequent response, release of information by WikiLeaks, the Icelandic ...

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... unlimited. It may be released to the Clearinghouse. DePartment of Comereforsae o te enga Page 2. EDITED TRANSLATION A ...

UK PubMed Central (United Kingdom)

A new analysis is presented which links real volume fractions, relaxation rates, and intracompartmental exchange rates directly with apparent volume fractions and relaxation rates obtained from biexponential...Full Text Available

UK PubMed Central (United Kingdom)

The effects of homologous plasma HDL and VHDL fractions on established atherosclerotic lesions were studied in cholesterol-fed rabbits. Atherosclerosis was induced by feeding the animals a 0.5% cholesterol-rich...Full Text Available

UK PubMed Central (United Kingdom)

Experiments were conducted to determine the dose response of rat bladder urothelium to a range of different single and fractionated intravesicular doses of the carcinogen, N-methyl-N-nitrosourea (MNU)....Full Text Available

UK PubMed Central (United Kingdom)

BACKGROUND: Accurate estimation of left ventricular ejection fraction (LVEF) has assumed great significance in the era of automatic implantable cardioverter defibrillators (AICDs), and a low EF may...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

When a certain void fraction value is reached in the two-phase flow regime, a problem occurs in the COBRA-EN code. This problem was observed in the drift-flux model option and interrupts code execution. Two solutions are proposed to solve the problem.

UK PubMed Central (United Kingdom)

A collection of neurons in the upper lumbar spinal cord of male rats projects to the lower lumbar spinal cord, releasing gastrin-releasing peptide (GRP) onto somatic and autonomic centers known to regulate...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

Hexane extract of licorice (Glycyrrhiza glabra L.) roots was obtained and investigated. Hydrocarbons, sterol ethers, triacylglycerides, free fatty acids, and free sterols were identified. The extract contains 70% neutral and 30% polar lipids. It is established that the lipid fraction of licorice roots is more effective than the analogous fraction of rosehip oil in stimulating the reparative regeneration of skin. In addition, this fraction also exhibits pronounced antiinflammatory and antiulcer effects, while being virtually nontoxic. Based on these results, the lipid fraction of licorice roots can be recommended as a parent substance for creating effective preparations in various medicinal forms.

CERN Document Server

System identification is a necessity in control theory. Classical control theory usually considers processes with integer order transfer functions. Real processes are usually of fractional order as opposed to the ideal integral order models. A simple and elegant scheme is presented for approximation of such a real world fractional order process by an ideal integral order model. A population of integral order process models is generated and updated by PSO technique, the fitness function being the sum of squared deviations from the set of observations obtained from the actual fractional order process. Results show that the proposed scheme offers a high degree of accuracy.

Energy Technology Data Exchange (ETDEWEB)

This report contains a set of nomographs which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorptance coefficient, and collector overall loss coefficient.

Energy Technology Data Exchange (ETDEWEB)

A set of nomographs is provided which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorption coefficient, and collector overall loss coefficient.

Science.gov (United States)

This report summarizes the results of an expert-opinion elicitation activity designed to qualitatively assess the status and capabilities of currently available computer codes and models for accident analysis and reactor safety calculations of advanced sodium fast reactors, and identify important gaps. The twelve-member panel consisted of representatives from five U.S. National Laboratories (SNL, ANL, INL, ORNL, and BNL), the University of Wisconsin, the KAERI, the JAEA, and the CEA. The major portion of this elicitation activity occurred during a two-day meeting held on Aug. 10-11, 2010 at Argonne National Laboratory. There were two primary objectives of this work: (1) Identify computer codes currently available for SFR accident analysis and reactor safety calculations; and (2) Assess the status and capability of current US computer codes to adequately model the required accident scenarios and associated phenomena, and ...

International Nuclear Information System (INIS)

An IAEA databank lists a number of reported cases of illicitly trafficked nuclear or other radioactive materials. Apart from the traditional concern with nuclear proliferation, the post September 11th public is now wary of a possible attack by terrorists with a nuclear or radiation dispersion device (RDD). Until now, the seized quantities have not been sufficient to manufacture a nuclear explosive device, but they might be enough to construct an RDD. Recognizing the latent global challenge to public health and safety, the G8 States (Japan, USA, Germany, France, UK, Italy, Canada, and Russia) have called for 'joint international efforts to identify and suppress illicit supply' of, and demand for, nuclear material and to deter potential traffickers. One measure gaining in significance is to identify seized material and trace it back to its origin the objective of an emerging science known as nuclear forensics. Repeatedly nuclear or other radioactive material of unknown origin are ...

British Library Electronic Table of Contents (United Kingdom)

The electroless nickel plating/poly(dl-lactide-co-glycolide) composite coating (EN-plating/PLGA composite coating) was fabricated on the surface of the micro-arc oxidation (MAO) film of the magnesium alloy AZ81 to double control the corrosion and drug release in the hanks' solution. The EN-plating was fabricated on the MAO coating to improve the corrosion resistance by overlaying most pores and micro-cracks on the surface of the MAO film. Meanwhile, a double layered organic poly(dl-lactide-co-glycolide)/paclitaxel (PLGA/PTX) drug releasing coating with a top layered PLGA drug controlled releasing coating on EN plating was prepared to control the drug release rate by adjusting the different lactide: glycolide (LA:GA) ratio of PLGA. Scanning electron microscopy (SEM) and the X-ray powder dif...

Energy Technology Data Exchange (ETDEWEB)

It has been reported by the present authors that behavior of tritium release from solid breeder grain is consisted of diffusion in grain, tritium transfer at surface layer and surface reactions on grain surface such as adsorption or isotope exchange reactions. Tritium release curves estimated using the tritium release model gave good agreement with observed tritium release curves from Li{sub 4}SiO{sub 4}, Li{sub 2}ZrO{sub 3} or LiAlO{sub 2}. Tritium release behavior from Li{sub 2}TiO{sub 3} under humid purge gas, dry purge gas and dry purge gas with hydrogen conditions is discussed in this study, tritium release curves using the release model that we proposed previously give a good agreements with experimental tritium release curves. Tritium effective diffusivity in the crystal grain of Li{sub 2}TiO{sub 3} is also ...

International Nuclear Information System (INIS)

Stable boiloff of core water during a severe LWR accident, that is, boiloff driven only by the decay power generated below the water level, is tractable analytically and is relatively insensitive to axial power distribution. As might be expected, calculated accident event times are sensitive to the fidelity of the decay power model. During later stages of boiloff, heat transfer or transport of energy from above the water level to the residual water can result in an unstable condition during which the boiloff rate increases greatly. The unstable boiloff phenomenon illustrates the highly nonlinear influence of core heat transfer during meltdown and emphasizes the great accuracy requirements which attend the modeling of the accident during periods of enhanced heat transfer when significant zirconium oxidation is possible.

British Library Electronic Table of Contents (United Kingdom)

Abstract:- Two motorcycle riders lost control of their vehicle, fell, and hit a guardrail, which acted as a blade and led to a rapid, fatal outcome. In one case, the high velocity of the body at the time of the impact resulted in complete detachment of the trunk. Reconstruction of the accident dynamics enabled the guardrail post to be identified as the means of injury in both cases. The two accidents occurred over a short period of time, highlighting a dangerous phenomenon that in less severe cases is presumably associated with different degrees of survivor disability. The accidents deserve mention, because a different design of the impact surface of the guardrail post might have prevented the lethal outcome. There is an urgent need for legislators to pass regulations that modify crash bar...

International Nuclear Information System (INIS)

SAMPSON is an integration of twelve analysis modules under the final development phase (phase-2) and will be capable of simulating hypothesized severe accidents in a nuclear power plant. One of these modules, the Molten Core Relocation Analysis (MCRA) module, simulates the relocation behavior of a molten core during a severe accident. MCRA models severe accident phenomena by using mechanistic formulations for multi-phase, multi-component, and multi-velocity field. As one of the verification studies of SAMPSON in Phase-1, the in-core phenomena of PHEBUS/FPT0 was analyzed with three modules, MCRA, fuel rod heat up analysis (FRHA) module, and the analysis control module (ACM) of SAMPSON. (author)

Energy Technology Data Exchange (ETDEWEB)

New measuring methods are developed and are tested with the small reactor simulator MIDAS (Mini Dodewaard ASsembly). The purpose of this work is to be able to measure accurately as many different properties of the flow as possible in the coming bigger simulator SIDAS (Simulated Dodewaard ASsembly). In SIDAS the flow around a fuel assembly of the Dutch Dodewaard reactor will be simulated. An extensive evaluation of the gamma detection system showed that the detection system could be simplified strongly. The simplified system is used to measure the radial and axial distribution of the void fraction in the core of MIDAS for three different operating conditions. Two new measuring methods have been developed and tested. A method to estimate the probability density of the void fraction in time. Due to the nonlinear relation between transmission and void fraction the determined average value of the void ...

UK PubMed Central (United Kingdom)

A patient is presented with a cervical spinal cord transection which occurred after a motor vehicle accident in which the air bag deployed and the seat belt was not in use. The patient had complete...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

This paper describes a functional slide rule that provides a readily usable ?in-hand? method for estimating nuclear criticality accident information from sliding graphs, thereby permitting (1) the rapid estimation of pertinent criticality accident information without laborious or sophisticated calculations in a nuclear criticality emergency situation, (2) the appraisal of potential fission yields and external personnel radiation exposures for facility safety analyses, and (3) a technical basis for emergency preparedness and training programs at nonreactor nuclear facilities. The slide rule permits the estimation of neutron and gamma dose rates and integrated doses based upon estimated fission yields, distance from the fission source, and time-after criticality accidents for five different critical systems. Another sliding graph permits the estimation of critical solution fission yields based upon fissile material ...

UK PubMed Central (United Kingdom)

BackgroundAlthough some previous studies have suggested that posttraumatic growth (PTG) is comprised of several factors with different properties, few have examined both the association...Full Text Available

Science.gov (United States)

at 4:30 P.M. November 30, 2006 - NTSB Sends Investigators to Metro Accident in Alexandria, Virginia November 27, 2006 - (SB-06-67) John Clark Assumes New Scientific Post at...

Energy Technology Data Exchange (ETDEWEB)

This study examines some radiation accidents occurred in the past. This information has been systematically assessed to get global lessons. The experience feedback shows that the most of accidents happened in certain conditions. These conditions can be distributed in four categories: 1- perception and vigilance in occupation: accidental exposure happened by lack of vigilance in details and lack of vigilance and perception; 2- procedures: accidental exposure happened following a lack of procedures or control that were not enough complete, not enough documented or not completely implemented; 3- training and understanding: accidental exposures happened because the personnel was not enough qualified and educated, did not get the general training nor the the necessary specialized training; 4- liabilities: accidental exposures happened following lacks and ambiguity in the definition of functions of the personnel and in the hierarchy liabilities. In ...

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The Global Road Safety Partnership (GRSP) is a global partnership of business, civil society and government working for sustained reduction of road accidents in developing and transition countries. GRSP, which started operations in 1999, has a global secr...

Energy Technology Data Exchange (ETDEWEB)

This article, published in issue 80 of 'l'ACROnique du nucleaire', aims to retrace the early steps in the consideration of the possibility of a nuclear accident in France, with the inclusion of 'non-institutional' participants and applying the lessons learned in Belarus in the contaminated territories around the Chernobyl nuclear power plant. After a review of the origin of the involvement of the Association pour le Controle de la Radioactivite dans l'Ouest (ACRO) in addressing post-accident issues alongside the populations living in an environment polluted by radioactivity, it discusses, from the critical viewpoint of an NGO, the context and the working method adopted for this examination. This is followed by some key elements of the programme and unresolved questions about the available body of knowledge which motivates research and about the method adopted for the work. The conclusion, ...

Energy Technology Data Exchange (ETDEWEB)

A study was made of the actions of the excitant neurotoxin, kainic acid, on the uptake and the release of D-(2,3-3H)aspartate (D-ASP) in slices of guinea pig cerebral neocortex and striatum. The slices took up D-ASP, reaching concentrations of the amino acid in the tissue which were 14-23 times that in the medium. Subsequently, electrical stimulation of the slices evoked a Ca2+-dependent release of a portion of the D-ASP. Kainic acid (10(-5)-10(-3) M) produced a dose-dependent inhibition of D-ASP uptake. The electrically evoked release of D-ASP was increased 1.6-2.0 fold by 10(-5) and 10(-4)M kainic acid. The kainate-enlarged release was Ca2+-dependent. Dihydrokainic acid, an analogue of kainic acid with little excitatory or toxic action, did not increase D-ASP release but depressed D-ASP uptake. Attempts were made to block the action of kainic acid with baclofen and pentobarbital, ...

Energy Technology Data Exchange (ETDEWEB)

This course in System Reliability and Analysis Techniques focuses on the probabilistic quantification of accident sequences and the link between accident sequences and consequences. Other sessions in this series focus on the quantification of system reliability and the development of event trees and fault trees. This course takes the viewpoint that event tree sequences or combinations of system failures and success are available and that Boolean equations for system fault trees have been developed and are available. 93 figs., 11 tabs.

Energy Technology Data Exchange (ETDEWEB)

This document contains the accident sequence analysis of internally initiated events for Grand Gulf, Unit 1 as it operates in the Low Power and Shutdown Plant Operational State 5 during a refueling outage. The report documents the methodology used during the analysis, describes the results from the application of the methodology, and compares the results with the results from two full power analyses performed on Grand Gulf.

International Nuclear Information System (INIS)

This paper proposes a model to explain tritium release behavior of an irradiated Li_4SiO_4 sample made by Forschungszentrum Karlsruhe. The release curves were obtained in a series of experiments carried out using out-pile temperature programmed desorption techniques in the Kyoto University Reactor (KUR). Tritium release curves obtained for different purge gas compositions (N_2, N_2 + H_2, N_2 + H_2O) were compared for selection of suitable conditions to determine the apparent diffusivity of tritium in a crystal grain of Li_4SiO_4.In the model formation, some mass transfer steps in the bulk of the crystal grain and those on the surface of the grain were taken into account, which were diffusion of tritium in the grain, adsorption and desorption of water on the surface of the grain, two types of isotope exchange reactions, and water formation reaction by the addition of hydrogen to the purge gas.Diffusivities of tritium in the ...

International Nuclear Information System (INIS)

The decommissioning of windscale Pile 2 Chimney resulted in the removal of one of most historically significant and prominent features of the Sellafield site. The project was the first large scale concrete ''free release'' operation to be undertaken on the Sellafield nuclear site, producing 4500 tons of concrete of which 3000 tons was demonstrated to be ''free release''. The paper describes the radiometric techniques employed in the characterisation and segregation of the concrete into low level waste (LLW), very low level waste (VLLW) and free release categories. It examines the robust solutions that were developed to meet the technical and regulatory challenges of the project, which included the definition of free release, the selection of averaging volumes, the testing and validation of the monitoring systems employed for ton quantities of concrete and the identification and removal of small numbers ...

Energy Technology Data Exchange (ETDEWEB)

According to enactment of reduced dose limit based on ICRP-60, the calculation of Derived Release Limits(DRL) on Wolsung NPPs was carried out. There are two methods of determination on DRL; that is MPC(Maximum Permissible Concentration) method and system analysis method. In order to use the system analysis method, lots of environmental data are necessary and complicated exposure pathway are considered. So we intend to apply MPC method that is sort of simple. In addition the calculated results were compared with derived release limit on Canadian nuclear power plant.

Energy Technology Data Exchange (ETDEWEB)

A state of the art review of two-phase void fraction models in smooth horizontal tubes is provided and a probabilistic two-phase flow regime map void fraction model is developed for refrigerants under condensation, adiabatic, and evaporation conditions in smooth, horizontal tubes. Time fraction information from a generalized probabilistic two-phase flow map is used to provide a physically based weighting of void fraction models for different flow regimes. The present model and void fraction models in the literature are compared to data from multiple sources including R11, R12, R134a, R22, R410A refrigerants, 4.26-9.58 mm diameter tubes, mass fluxes from 70 to 900 kg/m{sup 2} s, and a full quality range. The present model has a mean absolute deviation of 3.5% when compared to the collected database. (author)

International Nuclear Information System (INIS)

Maytenus ilicifolia Mart. ex Reissek is traditionally used in Brazil for treatment of gastric ulcers. Here we report the phytochemical investigation of an ethanol extract of M. ilicifolia leaves (EEMIL) aiming at the isolation of constituents which were used as chemical markers to monitor an activity-guided fractionation of a lyophilized aqueous extract of M. ilicifolia leaves (LAEMIL). From EEMIL, four flavonoids were isolated, namely the tri-flavonoid glycosides mauritianin (1), trifolin, (2) hyperin (4), and epi-catechin (5). Fractionation of LAEMIL led to 5 fractions which afforded the tetra-glycoside kaempferol derivative (3), and galactitol (6). LAEMIL and its fractions were evaluated in rats for their effects on gastric secretion volume and pH. HPLC (High Performance Liquid Chromatography) analysis revealed that only fractions containing the tri- and tetra-flavonoid ...

Science.gov (United States)

Challenges of robotic cars, sponsored by the Defense Advanced Research Projects Agency (DARPA) of the U.S. Defense Department. Carroll Cordes, recently retired USGS branch chief,...

International Nuclear Information System (INIS)

An effective procedure for removing _3H, Xe and Kr from irradiated fuels was demonstrated using Shippingport UO"2 fuel. The release characteristics of _3H, Kr, Xe, and I from irradiated nuclear fuel have been determined as a function of temperature and gaseous environment. Vacuum outgassing and a flowing gas stream have been used to vary the gaseous environment. Vacuum outgassing released about 99% of the _3H and 20% of both Kr and Xe within a 3 h at 1500_0C. Similar results were obtained using a carrier gas of He containing 6% H"2. However, a carrier gas containing only He resulted in the release of approximately 80% of the _3H and 99% of both Kr and Xe. These results indicate that the release of these volatile fission products from irradiated nuclear fuel is a function of the chemical composition of the gaseous environment. The rate of tritium release increased with increasing ...

Science.gov (United States)

... TEXT FORMAT (XML-MTF)....34 1. Public Beta Release 1.02 of MTF2XML Converter.....35 G ...

UK PubMed Central (United Kingdom)

The Agency for Toxic Substances and Disease Registry (ATSDR) is a public health agency with responsibility for assessing the public health implications associated with uncontrolled releases of hazardous...Full Text Available

Science.gov (United States)

Evolution in Space Radio Telescopes Reveal Youngest Stellar Corpse Gas Clouds in Whirlpool Galaxy Yield Important Clues Supporting Theory on Spiral Arms Starbust-driven Winds...

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be extremely limited or even negative due to higher maritime transport costs leading to a modal shift back to

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These cutting-edge developments will be used for future government and commercial launch systems and space transportation operations. ...

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... in the body. PTH is made by the parathyroid glands -- four small glands located in the neck behind ... is due to excess PTH release by the parathyroid glands. This excess occurs due to an enlargement of ...

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Proceedings of the 11th IWGS Proceedings of the 8th IOC TREP, Release 10 Barley QTL Community Curation Workbook CIMMYT International Nursery Data Brachypodium website Rye...

International Nuclear Information System (INIS)

... OTHER ENVIRONMENTAL POLLUTANT EFFECTS ON LIVING ORGANISMS

UK PubMed Central (United Kingdom)

The pleiotropic actions of neuromodulators on pre- and postsynaptic targets present challenges to disentangling the mechanisms underlying regulation of synaptic transmission. Within the striatum,...Full Text Available

Science.gov (United States)

18 months service for FERS; 60 months service for CSRS employees. the period covered by your accrued, donated, and advanced sick leave & accrued and ...

Science.gov (United States)

from a military fuel storage facility released about 80,000 gallons of kerosine-based jet fuel. Immediate and extensive recovery measures managed to contain the spill, but...

Science.gov (United States)

Zinn, John;. Hoerlin,. Herman; and Petschek,. Albert. G.: The Motion of Bomb. Debris. Following the Starfish. Test. Radiation. Trapped in the Earth's ...

Energy Technology Data Exchange (ETDEWEB)

The refrigerant two-phase flows in a distributor and a simulated plate heat exchanger with a single passage used in a compression-type refrigerator were visualized by real-time neutron radiography. For a distributor, the liquid fraction in the each tube was measured by some image processing method. On the other hand, for a plate heat exchanger, the two-dimensional distribution of void fraction was measured quantitatively by the umbra method. As a result, it was shown that the dynamic behaviors of refrigerant at the inlet of the section strongly affected on the performance, that is, a distribution performance of a distributor and a liquid distribution in a plate heat exchanger. (author)

CERN Document Server

Particle Swarm Optimization technique offers optimal or suboptimal solution to multidimensional rough objective functions. In this paper, this optimization technique is used for designing fractional order PID controllers that give better performance than their integer order counterparts. Controller synthesis is based on required peak overshoot and rise time specifications. The characteristic equation is minimized to obtain an optimum set of controller parameters. Results show that this design method can effectively tune the parameters of the fractional order controller.

CERN Document Server

The Proportional-Integral-Derivative Controller is widely used in industries for process control applications. Fractional-order PID controllers are known to outperform their integer-order counterparts. In this paper, we propose a new technique of fractional-order PID controller synthesis based on peak overshoot and rise-time specifications. Our approach is to construct an objective function, the optimization of which yields a possible solution to the design problem. This objective function is optimized using two popular bio-inspired stochastic search algorithms, namely Particle Swarm Optimization and Differential Evolution. With the help of a suitable example, the superiority of the designed fractional-order PID controller to an integer-order PID controller is affirmed and a comparative study of the efficacy of the two above algorithms in solving the optimization problem is also presented.

Science.gov (United States)

The first space photographs were obtained from V-2 rockets fired upwards from the ..... Some fraction of the incoming solar radiation is reflected towards a sensor ...

Energy Technology Data Exchange (ETDEWEB)

A high pressure piezometer is described with which pVT-measurements on solutions of gases in liquids like oils can be performed at pressures and temperatures up to 2000 bar and 440 K, respectively. The present investigations deal mainly with the system squalaneCO/sub 2/ at different mole fractions, but also with squalaneN/sub 2/. The high accuracy of the measurements reveals a pronounced structure of the pV-curves in dependence on temperature and mole fraction. At larger mole fractions is the unequivocal assignment of the phases ambiguous, and the representation of the experimental data in terms of an equation of state not possible for the whole pressure and temperature range. However, for solutions with lower mole fractions could be determined the saturation pressures and the isothermal compressibility in the unsaturated region. Furthermore, the molar excess volumes of the mixture have been calculated ...

CERN Document Server

We study dipolar bosons in a 1D optical lattice and identify a region in parameter space---strong coupling but relatively weak on-site repulsion---hosting a series of stable CDW states whose low-energy excitations, built from "fractional domain walls", are remarkably similar to those of non-abelian fractional quantum Hall states. Here, a conventional domain wall between translated CDW's may split by inserting strings of degenerate, but inequivalent, CDW states. Outside these insulating regions, we find numerous supersolids as well as a superfluid regime. The mentioned phases should be accessible experimentally, and in particular, the fractional domain walls can be created in the ground state using single-site addressing, i.e. by locally changing the chemical potential.

UK PubMed Central (United Kingdom)

Diffusion in the extracellular space (ECS) of the brain is constrained by the volume fraction and the tortuosity and a modified diffusion equation represents the transport behavior of many molecules...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

Determination of the radiocarbon (14C) content of airborne particulate matter yields insight into the proportion of the carbonaceous material derived from fossil and contemporary carbon sources. Daily samples of PM2.5 were collected by high-volume sampler at an urban background site in Birmingham, UK, and the fraction of 14C in both the total carbon, and in the organic and elemental carbon fractions, determined by two-stage combustion to CO2, graphitisation and quantification by accelerator mass spectrometry. OC and EC content was also determined by Sunset Analyzer. The mean fraction contemporary TC in the PM2.5 samples was 0.50 (range 0.27-0.66, n=26). There was no seasonality to the data, but there was a positive trend between fraction contemporary TC and magnitude of SOC/TC ratio and fo...

UK PubMed Central (United Kingdom)

The challenges of lung cancer radiotherapy are intra/inter-fraction tumor/organ anatomy/motion changes and the need to spare surrounding critical structures. Evolving radiotherapy technologies, such...Full Text Available

International Nuclear Information System (INIS)

Full text: Full text: The incomplete understanding of the complex mechanisms connected with the interaction between thermal-hydraulic and neutron kinetics still challenges the design and the operation of nuclear reactors and imposes the adoption of conservatism in the evaluation of safety limits. The recent availability of powerful computer and computational techniques together with the continuing increase in operational experience suggests the revisiting of those areas and the identification of design/operation requirements that can be relaxed. So far, almost all of the safety analyses of research reactors have been performed using conservative computational tools such as channel codes but, nowadays, the application of Best-Estimate (BE) methods constitutes a real necessity. The global aim of the current work is an attempt to apply the best-estimate system thermal-hydraulic code Relap5. For this purpose, the generic IAEA research reactor Benchmark problem is re-considered for proving ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Clonidine Extended Release Augmentation of Psychostimulants in ADHD ADHD a Risk Factor for Substance Abuse; Cognitive Deficits Not a Predictor Commentary on Kollins et al.; Clonidine XR Augmentation for ADHD Pharmacologic Treatment of Childhood Insomnias Effects of Guanfacine Extended Release on Alertness in ADHD Long Term ADHD Drug Treatment Bipolar Disorder Rates Similar Across Selected Countries Group CBT Alone or Group CBT Plus SSRIs in Childhood Anxiety Resolution of Quetiapine-Induced Oral Dyskinesia From the FDA

UK PubMed Central (United Kingdom)

Mechanisms underlying the release of paclitaxel (PTX) from poly(ethylene glycol)/poly(lactic-co-glycolic acid) (PEG/PLGA) blends were investigated by coherent anti-Stokes Raman scattering (CARS)...Full Text Available

Science.gov (United States)

A mathematical model describing the behavior of a gas of any density released into a turbulent atmosphere was developed. A numerical treatment was established for two dimensional flow. An understanding of the effects of accidental or continuous release wa...

Energy Technology Data Exchange (ETDEWEB)

The gastrin releasing peptide (GRP) receptor is becoming an increasingly attractive target for development of new radiolabeled peptides with diagnostic and therapeutic potential. The attractiveness of the GRP receptor as a target is based upon the functional expression of GRP receptors in several tumors of neuroendocrine origin including prostate, breast, and small cell lung cancer. This concise review outlines some of the efforts currently underway to develop new GRP receptor specific radiopharmaceuticals by employing a variety of radiometal chelation systems.