WorldWideScience

Sample records for chernobyl nuclear reactor

  1. Chernobyl and the safety of nuclear reactors in OECD countries

    International Nuclear Information System (INIS)

    This report assesses the possible bearing of the Chernobyl accident on the safety of nuclear reactors in OECD countries. It discusses analyses of the accident performed in several countries as well as improvements to the safety of RBMK reactors announced by the USSR. Several remaining questions are identified. The report compares RBMK safety features with those of commercial reactors in OECD countries and evaluates a number of issues raised by the Chernobyl accident

  2. Radioactive fallout from the Chernobyl nuclear reactor accident

    Energy Technology Data Exchange (ETDEWEB)

    Beiriger, J.M.; Failor, R.A.; Marsh, K.V.; Shaw, G.E.

    1987-08-01

    This report describes the detection of fallout in the United States from the Chernobyl nuclear reactor accident. As part of its environmental surveillance program, Lawrence Livermore National Laboratory maintained detectors for gamma-emitting radionuclides. Following the reactor accident, additional air filters were set out. Several uncommon isotopes were detected at the time the plume passed into the US. (TEM)

  3. Radioactive fallout from the Chernobyl nuclear reactor accident

    Energy Technology Data Exchange (ETDEWEB)

    Beiriger, J.M.; Failor, R.A.; Marsh, K.V.; Shaw, G.E.

    1987-03-23

    Following the accident at the nuclear reactor at Chernobyl, in the Soviet Union on April 26, 1986, we performed a variety of measurements to determine the level of the radioactive fallout on the western United States. We used gamma-spectroscopy to analyze air filters from the areas around Lawrence Livermore National Laboratory (LLNL), California, and Barrow and Fairbanks, Alaska. Milk from California and imported vegetables were also analyzed. The levels of the various fission products detected were far below the maximum permissible concentration levels.

  4. Chernobyl reactor transient simulation study

    International Nuclear Information System (INIS)

    This paper deals with the Chernobyl nuclear power station transient simulation study. The Chernobyl (RBMK) reactor is a graphite moderated pressure tube type reactor. It is cooled by circulating light water that boils in the upper parts of vertical pressure tubes to produce steam. At equilibrium fuel irradiation, the RBMK reactor has a positive void reactivity coefficient. However, the fuel temperature coefficient is negative and the net effect of a power change depends upon the power level. Under normal operating conditions the net effect (power coefficient) is negative at full power and becomes positive under certain transient conditions. A series of dynamic performance transient analysis for RBMK reactor, pressurized water reactor (PWR) and fast breeder reactor (FBR) have been performed using digital simulator codes, the purpose of this transient study is to show that an accident of Chernobyl's severity does not occur in PWR or FBR nuclear power reactors. This appears from the study of the inherent, stability of RBMK, PWR and FBR under certain transient conditions. This inherent stability is related to the effect of the feed back reactivity. The power distribution stability in the graphite RBMK reactor is difficult to maintain throughout its entire life, so the reactor has an inherent instability. PWR has larger negative temperature coefficient of reactivity, therefore, the PWR by itself has a large amount of natural stability, so PWR is inherently safe. FBR has positive sodium expansion coefficient, therefore it has insufficient stability it has been concluded that PWR has safe operation than FBR and RBMK reactors

  5. The Chernobyl reactor accident

    International Nuclear Information System (INIS)

    The documentation abstracted contains a complete survey of the broadcasts transmitted by the Russian wire service of the Deutsche Welle radio station between April 28 and Mai 15, 1986 on the occasion of the Chernobyl reactor accident. Access is given to extracts of the remarkable eastern and western echoes on the broadcasts of the Deutsche Welle. (HP)

  6. Medical lessons learned from chernobyl relative to nuclear detonations and failed nuclear reactors.

    Science.gov (United States)

    Dallas, Cham E

    2012-12-01

    The Chernobyl disaster in 1986 involved the largest airborne release of radioactivity in history, more than 100 times as much radioactivity as the Hiroshima and Nagasaki atomic bombs together. The resulting emergency response, administrative blunders, and subsequent patient outcomes from this large-scale radiological disaster provide a wealth of information and valuable lessons for those who may find themselves having to deal with the staggering consequences of nuclear war. Research findings, administrative strategies (successful and otherwise), and resulting clinical procedures from the Chernobyl experience are reviewed to determine a current utility in addressing the appropriate protocols for a medical response to nuclear war. As various myths are still widely associated with radiation exposure, attention is given to the realities of a mass casualty medical response as it would occur with a nuclear detonation.

  7. Medical lessons learned from chernobyl relative to nuclear detonations and failed nuclear reactors.

    Science.gov (United States)

    Dallas, Cham E

    2012-12-01

    The Chernobyl disaster in 1986 involved the largest airborne release of radioactivity in history, more than 100 times as much radioactivity as the Hiroshima and Nagasaki atomic bombs together. The resulting emergency response, administrative blunders, and subsequent patient outcomes from this large-scale radiological disaster provide a wealth of information and valuable lessons for those who may find themselves having to deal with the staggering consequences of nuclear war. Research findings, administrative strategies (successful and otherwise), and resulting clinical procedures from the Chernobyl experience are reviewed to determine a current utility in addressing the appropriate protocols for a medical response to nuclear war. As various myths are still widely associated with radiation exposure, attention is given to the realities of a mass casualty medical response as it would occur with a nuclear detonation. PMID:23241462

  8. Chernobyl reactor accident

    International Nuclear Information System (INIS)

    Following the accident at Chernobyl nuclear reactor, WHO organized on 6 May 1986 in Copenhagen a one day consultation of experts with knowledge in the fields of meteorology, radiation protection, biological effects, reactor technology, emergency procedures, public health and psychology in order to analyse the development of events and their consequences and to provide guidance as to the needs for immediate public health action. The present report provides detailed information on the transportation and dispersion of the radioactive material in the atmosphere, especially volatile elements, during the release period 26 April - 5 May. Presented are the calculated directions and locations of the radioactive plume over Europe in the first 5 days after the accident, submitted by the Swedish Meteorological and Hydrological Institute. The calculations have been made for two heights, 1500m and 750m and the plume directions are grouped into five periods, covering five European areas. The consequences of the accident inside the USSR and the radiological consequences outside the USSR are presented including the exposure routes and the biological effects, paying particular attention to iodine-131 effects. Summarized are the first reported measured exposure rates above background, iodine-131 deposition and concentrations in milk and the remedial actions taken in various European countries. Concerning the cesium-137 problem, based on the UNSCEAR assessment of the consequences of the nuclear fallout, one concludes that the cesium contamination outside the USSR is not likely to cause any serious problems. Finally, the conclusions and the recommendations of the meeting, taking into account both the short-term and longer term considerations are presented

  9. Chernobyl Nuclear Reactor accident fallout: Measurement and consequences. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-01

    The bibliography contains citations concerning the consequences of radioactive fallout from the Chernobyl nuclear reactor accident. Citations discuss radioactive monitoring, health hazards, and radiation dosimetry. Radiation contamination in the air, soil, vegetation, and food is examined. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  10. Chernobyl reactor accident: medical management

    International Nuclear Information System (INIS)

    Chernobyl reactor accident on 26th April, 1986 is by far the worst radiation accident in the history of the nuclear industry. Nearly 500 plant personnel and rescue workers received doses varying from 1-16 Gy. Acute radiation syndrome (ARS) was seen only in the plant personnel. 499 individuals were screened for ARS symptoms like nausea, vomitting, diarrhoea and fever. Complete blood examination was done which showed initial granulocytosis followed by granulocytopenia and lymphocytopenia. Cytogenetic examinations were confirmatory in classifying the patients on the basis of the doses received. Two hundred and thirty seven cases of ARS were hospitalised in the first 24-36 hrs. No member of general public suffered from ARS. There were two immediate deaths and subsequently 28 died in hospital and one of the cases died due to myocardial infarction, making a total of 31 deaths. The majority of fatal cases had whole body doses of about 6 Gy, besides extensive skin burns. Two cases of radiation burns had thermal burns also. Treatment of ARS consisted of isolation, barrier nursing, replacement therapy with fluid electrolytes, platelets and RBC transfusions and antibiotic therapy for bacterial, fungal and viral infections. Bone marrow transplantations were given to 13 cases out of which 11 died due to various causes. Radiation burns due to beta, gamma radiations were seen in 56 cases and treated with dressings, surgical excision, skin grafting and amputation. Oropharangeal syndrome, producing extensive mucous in the oropharynx, was first seen in Chernobyl. The patients were treated with saline wash of the mouth. The patients who had radioactive contamination due to radioactive iodine were given stable iodine, following wash with soap, water and monitored. Fourteen survivors died subsequently due to other causes. Late health effects seen so far include excess of thyroid cancer in the children and psychological disorders due to stress. No excess leukemia has been reported so

  11. ASSESSMENT OF THE RADIONUCLIDE COMPOSITION OF "HOT PARTICLES" SAMPLED IN THE CHERNOBYL NUCLEAR POWER PLANT FOURTH REACTOR UNIT

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E.; Jannik, T.; Marra, J.

    2011-10-01

    Fuel-containing materials sampled from within the Chernobyl Nuclear Power Plant (ChNPP) 4th Reactor Unit Confinement Shelter were spectroscopically studied for gamma and alpha content. Isotopic ratios for cesium, europium, plutonium, americium, and curium were identified and the fuel burnup in these samples was determined. A systematic deviation in the burnup values based on the cesium isotopes, in comparison with other radionuclides, was observed. The conducted studies were the first ever performed to demonstrate the presence of significant quantities of {sup 242}Cm and {sup 243}Cm. It was determined that there was a systematic underestimation of activities of transuranic radionuclides in fuel samples from inside of the ChNPP Confinement Shelter, starting from {sup 241}Am (and going higher), in comparison with the theoretical calculations.

  12. Chernobyl lesson and the nuclear power prospects

    International Nuclear Information System (INIS)

    At sixteen years from the disaster which made the commercial power reactor nr. 4 of the Chernobyl NPP known worldwide, the radiation effects and the consequences are still vivid. A basic statement is to be underlined, namely, the Chernobyl event was not an accident in a nuclear power plant being in an industrial, commercial state of operation but an accident following an experiment done on the reactor. Lack of professionalism, of nuclear safety culture, the outrageous violation of basic rules and regulations, established for the unit operation, represent some of the causes originating the Chernobyl disaster. One of the most unfair consequences enhanced by an incorrect mass media information and political manipulation was the ensuing antinuclear media campaign. The paper quotes recent monographs and United Nations Documents showing how the facts were distorted to render arguments and support for various political, economical or humanistic goals. Thus, over more than 15 years due to the hard controversies and irrational campaigns on a global scale the nuclear power was discredited. Practically, all the nuclear power plant constructions were either delayed or cancelled. Moreover, some governments have sustained even closing the existing nuclear stations. The author asks himself rhetorically whether somebody has considered and quantified the immense losses produced by such unmotivated policy or else the additional damage and abuse caused to our home planet by the additional burning of fossil fuels to replace the nuclear fuel burning in nuclear power plants. The paper ends by mentioning the environmental advantages and economic efficiency of that clean energy source which is the nuclear power

  13. Radiological consequences of the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    The reactor accident at unit 4 of the Chernobyl nuclear power plant in Ukraine has deeply affected the living conditions of millions of people. Especially the health consequences have been of public concern up to the present and also been the subject of sometimes absurd claims. The current knowledge on the radiological consequences of the accident is reviewed. Though an increased hazard for some risk groups with high radiation exposure, e.g., liquidators, still cannot be totally excluded for the future, the majority of the population shows no statistically significant indication of radiation-induced illnesses. The contribution of the Research Center Juelich to the assessment of the post-accidental situation and psychological relief of the population is reported. The population groups still requiring special attention include, in particular, children growing up in highly contaminated regions and the liquidators of the years 1986 and 1987 deployed immediately after the accident. (author)

  14. The Chernobyl catastrophe is the most terrible civil nuclear incident

    International Nuclear Information System (INIS)

    Full text: The 4th nuclear reactor of the Chernobyl NPP exploded on 26 April 1986, 20 years ago. It's the most terrible nuclear civil accident of all times. The consequences of the Chernobyl accident led to contamination of 3,1 million ha of arable land, 1,5 million ha of natural pasture land, 3,5 million ha of forests and changed the lifestyle for millions of people in Belarus, Ukraine and Russia. It is well known that the mortality in the contaminated areas (infant mortality by cancer) drastically increased. The Chernobyl catastrophe is presented , such as a sad example for humanity, a complex political international, economical, social and, particular, ecological problem according to the traditional and new studies for the development of the nucleotide contaminated territories: 1. Financing of safety of stopped working 4th nuclear reactor (security of covering system) and of work another 3 blocks at the Chernobyl NPP. Detailed control of international financial support for guarantee the safety, security of the Chernobyl NPP and sustainable development for rehabilitation of the affected zones and people. 2. It should be marked increase in medical, demographic analysis and in social, economical protection of the people in the contaminated areas. 3. Analysis and synthesis, monitoring of the long-time data results due to environmental, ecological, social and political consequences of the Chernobyl disaster. 4. Protection from the possible terrorist (extra) actions and (inter) damage or incident function of the Chernobyl plant, such as an old generation nuclear power. 5. Planned budget for future studies in the affected territories and flexibility actually realization of budget (State and International). 6. Nuclear refuse and aria/water protection in the Ukraine, Belarus and Russia contaminated zones. 7. Risk evaluation of not good function of NPPs which are situated in Russia, Ukraine and in another places (always remembering that the Chernobyl catastrophe is the

  15. Radiological consequences of the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    Fifty years of peaceful utilization of nuclear power were interrupted by the reactor accident in unit 4 of the Chernobyl nuclear power station in Ukraine in 1986, a disruptive event whose consequences profoundly affected the way of life of millions of people, and which has moved the public to this day. Releases of radioactive materials contaminated large areas of Belarus, the Russian Federation, and Ukraine. Early damage in the form of radiation syndrome was suffered by a group of rescue workers and members of the reactor operating crew, in some cases with fatal consequences, while the population does not, until now, show a statistically significant increase in the rate of late damage due to ionizing radiation expect for thyroid diseases in children. In particular, no increases in the rates of solid tumors, leukaemia, genetic defects, and congenital defects were detected. For some risk groups exposed to high radiation doses (such as liquidators) the hazard may still be greater, but the large majority of the population need not live in fear of serious impacts on health. Nevertheless, the accident shows major negative social and psychological consequences reinforced by the breakdown of the Soviet Union. This may be one reason for the observed higher incidence of other diseases whose association with the effects of radiation as a cause has not so far been proven. The measurement campaign conducted by the federal government in 1991-1993 addressed these very concerns of the public in an effort to provide unbiased information about exposures detected, on the one hand, in order to alleviate the fears of the public and reduce stress and, on the other hand, to contribute to the scientific evaluation of the radiological situation in the regions most highly exposed. The groups of the population requiring special attention in the future include especially children growing up in highly contaminated regions, and the liquidators of 1986 and 1987 employed in the period immediately

  16. Thyroid consequences of the Chernobyl nuclear accident.

    Science.gov (United States)

    Pacini, F; Vorontsova, T; Molinaro, E; Shavrova, E; Agate, L; Kuchinskaya, E; Elisei, R; Demidchik, E P; Pinchera, A

    1999-12-01

    It is well recognized that the use of external irradiation of the head and neck to treat patients with various non-thyroid disorders increases their risk of developing papillary thyroid carcinoma years after radiation exposure. An increased risk of thyroid cancer has also been reported in survivors of the atomic bombs in Japan, as well as in Marshall Island residents exposed to radiation during the testing of hydrogen bombs. More recently, exposure to radioactive fallout as a result of the Chernobyl nuclear reactor accident has clearly caused an enormous increase in the incidence of childhood thyroid carcinoma in Belarus, Ukraine, and, to a lesser extent, in the Russian Federation, starting in 1990. When clinical and epidemiological features of thyroid carcinomas diagnosed in Belarus after the Chernobyl accident are compared with those of naturally occurring thyroid carcinomas in patients of the same age group in Italy and France, it becomes apparent that the post-Chernobyl thyroid carcinomas were much less influenced by gender, virtually always papillary (solid and follicular variants), more aggressive at presentation and more frequently associated with thyroid autoimmunity. Gene mutations involving the RET proto-oncogene, and less frequently TRK, have been shown to be causative events specific for papillary cancer. RET activation was found in nearly 70% of the patients who developed papillary thyroid carcinomas following the Chernobyl accident. In addition to thyroid cancer, radiation-induced thyroid diseases include benign thyroid nodules, hypothyroidism and autoimmune thyroiditis, with or without thyroid insufficiency, as observed in populations after environmental exposure to radioisotopes of iodine and in the survivors of atomic bomb explosions. On this basis, the authors evaluated thyroid autoimmune phenomena in normal children exposed to radiation after the Chernobyl accident. The results demonstrated an increased prevalence of circulating thyroid

  17. The Chernobyl-4 Reactor and the possible causes of the accident

    International Nuclear Information System (INIS)

    A description and information about the Chernobyl nuclear reactor is given. Some comparison elements between the RBMK reactor type and GCR, CANDU, SGHWR and Hanford N reactor types are presented. A scenario of the possible causes of the accident is discussed. (A.F.)

  18. The Chernobyl Nuclear Power Plant accident: ecotoxicological update

    Science.gov (United States)

    Eisler, R.

    2003-01-01

    The accident at the Chernobyl, Ukraine, nuclear reactor on 26 April 1986 released large amounts of radiocesium and other radionuclides into the environment, contaminating much of the northern hemisphere, especially Europe. In the vicinity of Chernobyl, at least 30 people died, more than 115,000 others were evacuated, and consumption of milk and other foods was banned because of radiocontamination. At least 14,000 human cancer deaths are expected in Russia, Belarus, and the Ukraine as a direct result of Chernobyl. The most sensitive local ecosystems, as judged by survival, were the soil fauna, pine forest communities, and certain populations of rodents. Elsewhere, fallout from Chernobyl significantly contaminated freshwater and terrestrial ecosystems and flesh and milk of domestic livestock; in many cases, radionuclide concentrations in biological samples exceeded current radiation protection guidelines. Reindeer (Rangifer tarandus) in Scandinavia were among the most seriously afflicted by Chernobyl fallout, probably because their main food during winter (lichens) is an efficient absorber of airborne particles containing radiocesium. Some reindeer calves contaminated with 137Cs from Chernobyl showed 137Cs-dependent decreases in survival and increases in frequency of chromosomal aberrations. Although radiation levels in the biosphere are declining with time, latent effects of initial exposure--including an increased frequency of thyroid and other cancers--are now measurable. The full effect of the Chernobyl nuclear reactor accident on natural resources will probably not be known for at least several decades because of gaps in data on long-term genetic and reproductive effects and on radiocesium cycling and toxicokinetics.

  19. Collection, documentation and assessment of data measured in the Federal Republic of Germany after the reactor accident in the nuclear power plant at Chernobyl

    International Nuclear Information System (INIS)

    Representative for the Federal Republic of Germany, regions were selected that showed a lesser (Hesse) and higher (Bavaria) contamination. The contamination in individual environmental media (milk, i.a.) was demonstrated by values measured and assessed on a prognostic model and subsequently compared with each other. The intake was then evaluated on the basis of food basket and total body measurement data for determining the dose for various age groups and regions. Against those from food baskets, the doses derived from total body measurements were generally lower by 20-60%. This indicates change in consumption habits, adherence to recommendations and the effect of countermeasures, particularly in the higher contaminated southern region of the Federal Republic of Germany. The intake and dose assessments were compared to those measured during the time of contamination from fallout due to nuclear weapons tests. External radiation exposure and cumulative dose from fallout due to nuclear weapons tests and the Chernobyl accident were calculated. In 1986, the radiation exposure from external sources and from ingestion in consequence of the reactor accident had reached in the region of highest contamination (County of Berchtesgaden) 40%, in the lesser contaminated region (Hesse) about 5% of the average natural radiation exposure. (orig./HP)

  20. Consequences and countermeasures in a nuclear power accident: Chernobyl experience.

    Science.gov (United States)

    Kirichenko, Vladimir A; Kirichenko, Alexander V; Werts, Day E

    2012-09-01

    Despite the tragic accidents in Fukushima and Chernobyl, the nuclear power industry will continue to contribute to the production of electric energy worldwide until there are efficient and sustainable alternative sources of energy. The Chernobyl nuclear accident, which occurred 26 years ago in the former Soviet Union, released an immense amount of radioactivity over vast territories of Belarus, Ukraine, and the Russian Federation, extending into northern Europe, and became the most severe accident in the history of the nuclear industry. This disaster was a result of numerous factors including inadequate nuclear power plant design, human errors, and violation of safety measures. The lessons learned from nuclear accidents will continue to strengthen the safety design of new reactor installations, but with more than 400 active nuclear power stations worldwide and 104 reactors in the Unites States, it is essential to reassess fundamental issues related to the Chernobyl experience as it continues to evolve. This article summarizes early and late events of the incident, the impact on thyroid health, and attempts to reduce agricultural radioactive contamination.

  1. A preliminary assessment of individual doses in the environs of Berkeley, Gloucestershire, following the Chernobyl nuclear reactor accident

    International Nuclear Information System (INIS)

    A preliminary assessment has been made of the individual doses to critical group members of the public in the environs of Berkeley arising from fallout resulting from the Chernobyl accident. The assessment was based on measurements of airborne radionuclide concentrations, ground deposition and nuclide concentrations in rainwater, tapwater, grass, milk and green vegetables. The committed effective dose-equivalent was found to be as follows:- Adult - 200 μSv, 1 year old child - 500 μSv, the 10 year old child receiving a dose intermediate between these two values. The estimate accounts only for the nuclides measured and the specific exposure routes considered namely ingestion of milk and vegetables, inhalation and external exposure. However, it is believed that the inclusion of a range of other nuclides of potential significance, which may have been present but not measured, and potential intakes from additional routes is unlikely to increase the above estimates by more than a factor of 2. (author)

  2. Measured transfer factors in milk and meat after the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    After the nuclear reactor accident at Chernobyl the radioactivity in the environment in Aachen was measured in detail at the Lehrgebiet Strahlenschutz in der Kerntechnik. The change of the different radionuclides in the eco-system made it possible to obtain radioecological parameters especially for iodine and caesium. The knowledge about the transport of iodine into cow's milk could be very much improved

  3. Radioactivity monitoring by the official monitoring stations in North-Rhine Westphalia and the Juelich Nuclear Research Centre after the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    This official report presents a governmental declaration of the prime minister of NRW, Mr. Rau, concerning the reactor accident at Chernobyl, and a joint declaration of ministers of NRW, concerning the impact of the accident on the Land NRW. These statements are completed by six official reports on radioactivity measurements carried out by the official monitoring stations of the Land and by the KFA Juelich. These reports inform about methods, scope, and results of the measuring campaigns accomplished by the Zentralstelle fuer Sicherheitstechnik (ZFS), the public materials testing office (MPA), the Chemisches Untersuchungsamt, the Landesamt fuer Wasser und Abfall, and the KFA Juelich. (DG)

  4. Radiation exposure: Cytogenetic tests. Chernobyl reactor accident

    International Nuclear Information System (INIS)

    Forty test subjects who, either during or after the reactor accident of Chernobyl (26th April 1986), stayed at a building site at Shlobin 150 km away, were examined for spontaneously occurring as well as mitomycin C-induced Sister Chromatid Exchanges (SCE). The building site staff, who underwent a whole-body radionuclide count upon their return to Austria (June through September 1986), were used for the cytogenetic tests. The demonstration of the SCE was made from whole-blood cultures by the fluorescence/Giemse technique. At last 20 Metaphases of the 2nd mitotic cycle were evaluated per person. The radiation doses of the test subjects were calculated by adding the external exposure determined on the building site, the estimated thyroid dose through I-131, and the measured incorporation of Cs-134 and Cs-137. The subjects were divided into two groups for statistical analysis: One was a more exposed group (proven stay at Shlobin between 26th April and 31st May 1986, mostly working in the open air) and the other a less exposed group for comparison (staying at Shlobin from 1st Juni 1986 and working mainly indoors). (orig.)

  5. Health consequences of Chernobyl. 25 years after the reactor catastrophy

    International Nuclear Information System (INIS)

    The report is an evaluation of studies indicating health effects as a consequence of the reactor catastrophe in Chernobyl. The most exposed population include the cleaning personnel (liquidators), the population evacuated from the 30 km zone, the populations in highly contaminated regions in Russia, Belarus and Ukraine, the European population in lass contaminated regions. The following issues are discussed: the liquidators, infant mortality, genetic and teratogenic damages, thyroid carcinoma and other thyroid diseases, carcinogenic diseases and leukemia, other diseases following the Chernobyl catastrophe.

  6. After the Chernobyl reactor accident: Just got away?

    International Nuclear Information System (INIS)

    The feeling of depression and insecurity experienced immediately after the Chernobyl reactor accident has gone by, and people go out for a walk again, and drink their milk. Are we happily aware we got away with it this time, or is it rather a feeling of resignation that makes us return to normal life? The Chernobyl disaster will only after some time be really assessed in its novel, global dimension. (orig.)

  7. [The radioecology of the grapevine. 2. Effects of the nuclear reactor accident in Chernobyl on the radioactivity in the soil, leaves, grapes and wine].

    Science.gov (United States)

    Wagner, A; Diehl, J F

    1991-04-01

    Natural (tritium, 14C, 40K, 226Ra) and man-made radionuclides (90Sr, 134Cs, 137Cs) were determined in soil (top 30 cm), vine leaves, grapes and wine in eight locations of the most important viticultural regions in the Federal Republic of Germany. The results obtained in 1983-1985 have been published previously. Part II of this study presents results obtained in 1986 and 1987, i.e. after the reactor accident at Chernobyl in the Soviet Union. The mean content of 137Cs before (after) Chernobyl was 4 (9) Bq/kg dry matter in soil, 0.07 (3) Bq/kg fresh matter in leaves, 0.02 (0.4) Bq/kg in grapes, and 0.008 (0.9) Bq/L in wine. As compared with 1986, distinctly lower levels were found in leaves, grapes and wine in 1987. In 1986 the content of 134Cs was about half that of 137Cs. Owing to its shorter half-life, 134Cs was below the detection limit in many of the 1987 samples. Transfer factors such as from soil to leaves and from soil to grapes for caesium agreed well in 1983-1985 and 1987, but showed considerable deviations in 1986, due to the ubiquitous contamination of the environment. Results of 90Sr determinations confirmed other reports showing this radionuclide to be a very minor contributor to the total radioactivity released at Chernobyl. No effect of the reactor accident on levels of the other radionuclides was detected.

  8. Generalities about nuclear reactors

    International Nuclear Information System (INIS)

    From Zoe, the first nuclear reactor, till the current EPR, the French nuclear industry has always advanced by profiting from the feedback from dozens of years of experience and operations, in particular by drawing lessons from the most significant events in its history, such as the Fukushima accident. The new generations of reactors must improve safety and economic performance so that the industry maintain its legitimacy and its share in the production of electricity. This article draws the history of nuclear power in France, gives a brief description of the pressurized water reactor design, lists the technical features of the different versions of PWR that operate in France and compares them with other types of reactors. The feedback experience concerning safety, learnt from the major nuclear accidents Three Miles Island (1979), Chernobyl (1986) and Fukushima (2011) is also detailed. Today there are 26 third generation reactors being built in the world: 4 EPR (1 in Finland, 1 in France and 2 in China); 2 VVER-1200 in Russia, 8 AP-1000 (4 in China and 4 in the Usa), 8 APR-1400 (4 in Korea and 4 in UAE), and 4 ABWR (2 in Japan and 2 in Taiwan)

  9. The Chernobyl nuclear accident and its consequences

    International Nuclear Information System (INIS)

    An AAEC Task Group was set up shortly after the accident at the Chernobyl Nuclear Power Plant to monitor and evaluate initial reports and to assess the implications for Australia. The Task Group issued a preliminary report on 9 May 1986. On 25-29 August 1986, the USSR released details of the accident and its consequences and further information has become available from the Nuclear Energy Agency of OECD and the World Health Organisation. The Task Group now presents a revised report summarising this information and commenting on the consequences from the Australian viewpoint

  10. Evaluation of Radiation Impacts of Spent Nuclear Fuel Storage (SNFS-2) of Chernobyl NPP - 13495

    International Nuclear Information System (INIS)

    Radiation effects are estimated for the operation of a new dry storage facility for spent nuclear fuel (SNFS-2) of Chernobyl NPP RBMK reactors. It is shown that radiation exposure during normal operation, design and beyond design basis accidents are minor and meet the criteria for safe use of radiation and nuclear facilities in Ukraine. (authors)

  11. NUCLEAR REACTOR

    Science.gov (United States)

    Anderson, C.R.

    1962-07-24

    A fluidized bed nuclear reactor and a method of operating such a reactor are described. In the design means are provided for flowing a liquid moderator upwardly through the center of a bed of pellets of a nentron-fissionable material at such a rate as to obtain particulate fluidization while constraining the lower pontion of the bed into a conical shape. A smooth circulation of particles rising in the center and falling at the outside of the bed is thereby established. (AEC)

  12. NUCLEAR REACTOR

    Science.gov (United States)

    Miller, H.I.; Smith, R.C.

    1958-01-21

    This patent relates to nuclear reactors of the type which use a liquid fuel, such as a solution of uranyl sulfate in ordinary water which acts as the moderator. The reactor is comprised of a spherical vessel having a diameter of about 12 inches substantially surrounded by a reflector of beryllium oxide. Conventionnl control rods and safety rods are operated in slots in the reflector outside the vessel to control the operation of the reactor. An additional means for increasing the safety factor of the reactor by raising the ratio of delayed neutrons to prompt neutrons, is provided and consists of a soluble sulfate salt of beryllium dissolved in the liquid fuel in the proper proportion to obtain the result desired.

  13. Documents, used for drawing up the CCRX-report 'Radioactive contamination in the Netherlands caused by the reactor accident at Chernobyl'. Part 1

    International Nuclear Information System (INIS)

    In these documents the results are summarized of a large number of measurements and calculations performed by various Dutch organizations in consequence of the nuclear reactor accident at Chernobyl. refs.; figs.; tabs

  14. Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hogerton, John

    1964-01-01

    This pamphlet describes how reactors work; discusses reactor design; describes research, teaching, and materials testing reactors; production reactors; reactors for electric power generation; reactors for supply heat; reactors for propulsion; reactors for space; reactor safety; and reactors of tomorrow. The appendix discusses characteristics of U.S. civilian power reactor concepts and lists some of the U.S. reactor power projects, with location, type, capacity, owner, and startup date.

  15. The consequences of the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    After the decay of the iodine isotopes the measuring campaigns, in addition to the measuring of soil pollution and pollution of products, concentrated on the way of the cesium isotopes through the food chain, especially in crops, milk, meat and mother's milk. A special programme was developed for the analysis of foreign basic substances for teas, essences and tinctures. In connection with the incorporation measurements in the university hospital Eppendorf the measurement campaigns provided the data material in order to calculate with the aid of the computer program ECOSYS of the GSF the effective dose equivalent which the inhabitants of Hamburg additionally take up due to the accident of Chernobyl. Consequences with regard to measuring methods and social consequences are mentioned. (DG)

  16. 30 years life with Chernobyl, 5 years life with Fukushima. Health consequences of the nuclear catastrophes of Chernobyl and Fukushima

    International Nuclear Information System (INIS)

    The IPPNW report on health consequences of the nuclear catastrophes of Chernobyl and Fukushima covers the following issues: Part.: 30 years life with Chernobyl: Summarized consequences of Chernobyl, the accident progression, basic data of the catastrophe, estimation of health hazards as a consequence of the severe accident of Chernobyl, health consequences for the liquidators, health consequences for the contaminated population, mutagenic and teratogenic effects. Part B: 5 years life with Fukushima: The start of the nuclear catastrophe, emissions and contamination, consequences of the nuclear catastrophe on human health, thyroid surveys in the prefecture Fukushima, consequences of the nuclear catastrophe on the ecosystem, outlook.

  17. Nuclear reactor

    International Nuclear Information System (INIS)

    A nuclear reactor is described in which the core components, including fuel-rod assemblies, control-rod assemblies, fertile rod-assemblies, and removable shielding assemblies, are supported by a plurality of separate inlet modular units. These units are referred to as inlet module units to distinguish them from the modules of the upper internals of the reactor. The modular units are supported, each removable independently of the others, in liners in the supporting structure for the lower internals of the reactor. The core assemblies are removably supported in integral receptacles or sockets of the modular units. The liners, units, sockets and assemblies have inlet openings for entry of the fluid. The modular units are each removably mounted in the liners with fluid seals interposed between the opening in the liner and inlet module into which the fluid enters in the upper and lower portion of the liner. Each assembly is similarly mounted in a corresponding receptacle with fluid seals interposed between the openings where the fluid enters in the lower portion of the receptacle or fitting closely in these regions. As fluid flows along each core assembly a pressure drop is produced along the fluid so that the fluid which emerges from each core assembly is at a lower pressure than the fluid which enters the core assembly. However because of the seals interposed in the mountings of the units and assemblies the pressures above and below the units and assemblies are balanced and the units are held in the liners and the assemblies are held in the receptacles by their weights as they have a higher specific gravity than the fluid. The low-pressure spaces between each module and its liner and between each core assembly and its module is vented to the low-pressure regions of the vessel to assure that fluid which leaks through the seals does not accumulate and destroy the hydraulic balance

  18. Transgenic plants are sensitive bioindicators of nuclear pollution caused by the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Kovalchuk, I.; Kovalchuk, O. [Ivano-Frankivsk State Medical Academy (Ukraine)]|[Friedrich Miescher Inst., Basel (Switzerland); Arkhipov, A. [Chernobyl Scientific and Technical Center of International Research (Ukraine); Hohn, B. [Friedrich Miescher Inst., Basel (Switzerland)

    1998-11-01

    To evaluate the genetic consequences of radioactive contamination originating from the Nuclear reactor accident of Chernobyl on indigenous populations of plants and animals, it is essential to determine the rates of accumulating genetic changes in chronically irradiated populations. An increase in germline mutation rates in humans living close to the Chernobyl Nuclear Power Plant site, and a two- to tenfold increase in germline mutations in barn swallows breeding in Chernobyl have been reported. Little is known, however, about the effects of chronic irradiation on plant genomes. Ionizing radiation causes double-strand breaks in DNA, which are repaired via illegitimate or homologous recombination. The authors make use of Arabidopsis thaliana plants carrying a {beta}-glucuronidase marker gene as a recombination substrate to monitor genetic alterations in plant populations, which are caused by nuclear pollution of the environment around Chernobyl. A significant increase in somatic intrachromosomal recombination frequencies was observed at nuclear pollution levels from 0.1--900 Ci/km{sup 2}, consistent with an increase in chromosomal aberrations. This bioindicator may serve as a convenient and ethically acceptable alternative to animal systems.

  19. Nuclear research reactors

    International Nuclear Information System (INIS)

    It's presented data about nuclear research reactors in the world, retrieved from the Sien (Nuclear and Energetic Information System) data bank. The information are organized in table forms as follows: research reactors by countries; research reactors by type; research reactors by fuel and research reactors by purpose. (E.G.)

  20. Nuclear reactor

    International Nuclear Information System (INIS)

    In order to reduce neutron embrittlement of the pressue vessel of an LWR, blanked off elements are fitted at the edge of the reactor core, with the same dimensions as the fuel elements. They are parallel to each other, and to the edge of the reactor taking the place of fuel rods, and are plates of neutron-absorbing material (stainless steel, boron steel, borated Al). (HP)

  1. Chernobyl nuclear accident: Effects on food. (Latest citations from the Food Science and Technology Abstracts database). Published Search

    International Nuclear Information System (INIS)

    The bibliography contains citations concerning studies and measurements of the radioactive contamination by the Chernobyl nuclear reactor accident of food and the food chain. The studies cover meat and dairy products, vegetables, fish, food chains, and radioactive contamination of agricultural farms and lands. (Contains 250 citations and includes a subject term index and title list.)

  2. Immediate medical consequences of nuclear accidents: lessons from Chernobyl

    International Nuclear Information System (INIS)

    The immediate medical response to the nuclear accident at the Chernobyl nuclear power station involved containment of the radioactivity and evacuation of the nearby population. The next step consisted of assessment of the radiation dose received by individuals, based on biological dosimetry, and treatment of those exposed. Medical care involved treatment of skin burns; measures to support bone marrow failure, gastrointestinal tract injury, and other organ damage (i.e., infection prophylaxis and transfusions) for those with lower radiation dose exposure; and bone marrow transplantation for those exposed to a high dose of radiation. At Chernobyl, two victims died immediately and 29 died of radiation or thermal injuries in the next three months. The remaining victims of the accident are currently well. A nuclear accident anywhere is a nuclear accident everywhere. Prevention and cooperation in response to these accidents are essential goals

  3. Lessons of the Chernobyl Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    Insensitivity of radiation without measuring apparatus and health outcome observed in the atomic bomb survivors of Hiroshima and Nagasaki are major sources that make people fear the possible late effects of radiation exposure attributable to nuclear power plant accident. However, the health conditions of people in the last 20 years around Chernobyl indicated the necessity to review the risk assessment suggesting that effects of radiation exposure may considerably be different between the atomic bombing and nuclear power plant accident. (author)

  4. Nuclear reactor physics

    CERN Document Server

    Stacey, Weston M

    2010-01-01

    Nuclear reactor physics is the core discipline of nuclear engineering. Nuclear reactors now account for a significant portion of the electrical power generated worldwide, and new power reactors with improved fuel cycles are being developed. At the same time, the past few decades have seen an ever-increasing number of industrial, medical, military, and research applications for nuclear reactors. The second edition of this successful comprehensive textbook and reference on basic and advanced nuclear reactor physics has been completely updated, revised and enlarged to include the latest developme

  5. What did change in the FRG after the Chernobyl reactor accident? On the situation in churches

    International Nuclear Information System (INIS)

    The author discusses in detail the implications of the reactor desaster of Chernobyl both in terms of social ethics and theology and demonstrates processes within the churches and official church statements. (DG)

  6. The accident at the Chernobyl' nuclear power plant and its consequences

    International Nuclear Information System (INIS)

    The material is taken from the conclusions of the Government Commission on the causes of the accident at the fourth unit of the Chernobyl' nuclear power plant and was prepared by a team of experts appointed by the USSR State Committee on the Utilization of Atomic Energy. It contains general material describing the accident, its causes, the action taken to contain the accident and to alleviate its consequences, the radioactive contamination and health of the population and some recommendations for improving nuclear power safety. 7 annexes are devoted to the following topics: water-graphite channel reactors and operating experience with RBMK reactors, design of the reactor plant, elimination of the consequences of the accident and decontamination, estimate of the amount, composition and dynamics of the discharge of radioactive substances from the damaged reactor, atmospheric transport and radioactive contamination of the atmosphere and of the ground, expert evaluation and prediction of the radioecological state of the environment in the area of the radiation plume from the Chernobyl' nuclear power station, medical-biological problems. A separate abstract was prepared for each of these annexes. The slides presented at the post-accident review meeting are grouped in two separate volumes

  7. Report on the accident at the Chernobyl Nuclear Power Station

    International Nuclear Information System (INIS)

    This report presents the compilation of information obtained by various organizations regarding the accident (and the consequences of the accident) that occurred at Unit 4 of the nuclear power station at Chernobyl in the USSR on April 26, 1986. The various authors are identified in a footnote to each chapter. An overview of the report is provided. Very briefly the other chapters cover: the design of the Chernobyl nuclear station Unit 4; safety analyses for Unit 4; the accident scenario; the role of the operator; an assessment of the radioactive release, dispersion, and transport; the activities associated with emergency actions; and information on the health and environmental consequences from the accident. These subjects cover the major aspects of the accident that have the potential to present new information and lessons for the nuclear industry in general

  8. Compendium of the Environmental Measurements Laboratory's research projects related to the Chernobyl nuclear accident

    International Nuclear Information System (INIS)

    Following the accident at the Chernobyl nuclear reactor power station in the USSR on April 26, 1986, the Environmental Measurements Laboratory (EML) initiated a number of research projects as follows: (1) selected sites in both the Deposition and Surface Air networks were alerted and their sampling protocols adjusted to accommodate the anticipated arrival times and activity concentrations of the Chernobyl debris; (2) a number of cooperative programs involving field work, sampling, analysis and data interpretation were set up with institutions and scientists in other countries; (3) EML's Regional Baseline Station at Chester, NJ, as well as the roof of the Laboratory in New York City, provided bases for sampling and measurements to study the radionuclide concentrations, radiation levels, physical characteristics and potential biological implications of the Chernobyl fallout on the northeastern United States; and (4) the resulting fallout from the Chernobyl accident provided an 'experiment of opportunity' in that it enabled us to study fresh fission product deposition using collection systems resurrected from the 1950's and 1960's for comparison with current state-of-the-art methodology. The 13 reports of this volume have been entered separately into the data base

  9. Compendium of the Environmental Measurements Laboratory's research projects related to the Chernobyl nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Volchok, H L; Chieco, N [comps.

    1986-10-01

    Following the accident at the Chernobyl nuclear reactor power station in the USSR on April 26, 1986, the Environmental Measurements Laboratory (EML) initiated a number of research projects as follows: (1) selected sites in both the Deposition and Surface Air networks were alerted and their sampling protocols adjusted to accommodate the anticipated arrival times and activity concentrations of the Chernobyl debris; (2) a number of cooperative programs involving field work, sampling, analysis and data interpretation were set up with institutions and scientists in other countries; (3) EML's Regional Baseline Station at Chester, NJ, as well as the roof of the Laboratory in New York City, provided bases for sampling and measurements to study the radionuclide concentrations, radiation levels, physical characteristics and potential biological implications of the Chernobyl fallout on the northeastern United States; and (4) the resulting fallout from the Chernobyl accident provided an 'experiment of opportunity' in that it enabled us to study fresh fission product deposition using collection systems resurrected from the 1950's and 1960's for comparison with current state-of-the-art methodology. The 13 reports of this volume have been entered separately into the data base.

  10. 15 years after Chernobyl. Nuclear power and climate change?

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, M

    2001-04-01

    Fifteen years after two massive explosions and a subsequent fire released a giant radioactive cloud into the atmosphere over the Chernobyl nuclear power plant located in what used to be the USSR, 388 farms with 230,000 sheep in Wales, England and Scotland are still subject to restriction orders. The contamination levels stand at several hundred Becquerels of cesium per kilogram of meat, too much to be consumed by human beings. The sheep have to be moved for some time to low or non-contaminated pastures in order to allow the bodies to loose some of their radioactivity before they can be slaughtered. For many countries the 1986 Chernobyl catastrophe came a public turning point for the future of nuclear energy. (author)

  11. Soviet medical response to the Chernobyl nuclear accident

    International Nuclear Information System (INIS)

    The nuclear accident at Chernobyl was the worst in the history of nuclear power. It tested the organized medical response to mass radiation casualties. This article reviews the Soviet response as reported at the 1986 postaccident review meeting in Vienna and as determined from interviews. The Soviets used three levels of care: rescue and first aid at the plant site; emergency treatment at regional hospitals; and definitive evaluation and treatment in Moscow. Diagnosis, triage, patient disposition, attendant exposure, and preventive actions are detailed. The United States would be well advised to organize its resources definitively to cope with future nonmilitary nuclear accidents

  12. The nuclear safety account and the Chernobyl nuclear power plant

    International Nuclear Information System (INIS)

    In 1993, the G-7 officially proposed that the European Bank for Reconstruction and Development set up the Nuclear Safety Account (NSA) and act as the Account's secretariat. The Bank's Board of Directors approved this proposal and the Rules of the NSA on 22 March 1993 and the NSA became effective on 14 April 1993. The NSA finances, through grants, operational and near-term technical safety improvements for Soviet-designed nuclear reactors in the countries of the former Soviet Union, central and eastern Europe. Priority is given to those reactors which present the highest level of risk that can be significantly reduced by short-term and cost-effective safety improvements, and which are necessary to ensure the continuing electricity supply in the region. Efforts are therefore focused on WWER 440/230 and RBMK types of reactors and on the purchase of equipment as opposed to studies, which a number of donors already fund. Finance from the NSA is not used to extend the operating lifetime of unsafe reactors

  13. Fossil nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Maurette, M.

    1976-01-01

    The discussion of fossil nuclear reactors (the Oklo phenomenon) covers the earth science background, neutron-induced isotopes and reactor operating conditions, radiation-damage studies, and reactor modeling. In conclusion possible future studies are suggested and the significance of the data obtained in past studies is summarized. (JSR)

  14. Research Nuclear Reactors

    International Nuclear Information System (INIS)

    Published in English and in French, this large report first proposes an overview of the use and history of research nuclear reactors. It discusses their definition, and presents the various types of research reactors which can be either related to nuclear power (critical mock-ups, material test reactors, safety test reactors, training reactors, prototypes), or to research (basic research, industry, health), or to specific particle physics phenomena (neutron diffraction, isotope production, neutron activation, neutron radiography, semiconductor doping). It reports the history of the French research reactors by distinguishing the first atomic pile (ZOE), and the activities and achievements during the fifties, the sixties and the seventies. It also addresses the development of instrumentation for research reactors (neutron, thermal, mechanical and fission gas release measurements). The other parts of the report concern the validation of neutronics calculations for different reactors (the EOLE water critical mock-up, the MASURCA air critical mock-up dedicated to fast neutron reactor study, the MINERVE water critical mock-up, the CALIBAN pulsed research reactor), the testing of materials under irradiation (OSIRIS reactor, laboratories associated with research reactors, the Jules Horowitz reactor and its experimental programs and related devices, irradiation of materials with ion beams), the investigation of accident situations (on the CABRI, Phebus, Silene and Jules Horowitz reactors). The last part proposes a worldwide overview of research reactors

  15. Analysis of fluid-structure interaction and structural response of Chernobyl-4 reactor

    International Nuclear Information System (INIS)

    On April 26, 1986, an accident occurred at the Chernobyl-4 Nuclear Power Plant in the Soviet Union. A post accident meeting was held in Vienna during the week of August 25, 1986. In mid-July 1986, the DOE formed a team to analyze the accident, including experts from the national laboratories such as Argonne National Laboratory, Brookhaven National Laboratory, Oak Ridge National Laboratory, and Pacific Northwest Laboratory. The goal was to assess the information's plausibility, provided analytical support to the US delegation during the post-accident review meeting and obtain a technical understanding of the accident. Detailed analyses of the team work are given in Ref. 1 (DOE, 1986). The accident at Chernobyl-4 occurred during the running of a test to determine a turbogenerator's ability to provide in-house emergency power after shutting off its steam supply. The accident was the result of a large, destructive power excursion. The major design related factor in the accident was the large positive void coefficient of reactivity. This feature, not present in the US reactors, means that an increase in power is likely to lead to an increase in reactivity which will further increase power, and finally result in the destructive accident. 5 refs., 11 figs

  16. Radioactivity measurements in Krakow surroundings in the aftermath of Chernobyl reactor accident

    International Nuclear Information System (INIS)

    A team from different laboratories of the Institute of Nuclear Physics was formed to set a crash program of measurement of water and food contamination after the Chernobyl reactor accident. The main contaminants in the first days were 131I and 132Te which were superseded later on by 104Ru, 137Cs and 134Cs. The highest value of contamination of surface waters by 131I was attained in the Vistula river on the 2-nd of May with 530 Bq/dm3. Also measurements of food contamination by 131I,134Cs, 137Cs and 137Te were carried out. The additional effective dose equivalent related to Chernobyl accident received by the population of Krakow region in May 1986 was estimated at 0.45 mSV (45 rem). Another rise of 134Cs + 137Cs content up to 46 Bq/dm3 in cows milk was observed during March and April 1987 and was probably explicable by the use of hay harvested in June 1986. (author)

  17. Radioactive Waste Management In The Chernobyl Exclusion Zone - 25 Years Since The Chernobyl Nuclear Power Plant Accident

    International Nuclear Information System (INIS)

    Radioactive waste management is an important component of the Chernobyl Nuclear Power Plant accident mitigation and remediation activities of the so-called Chernobyl Exclusion Zone. This article describes the localization and characteristics of the radioactive waste present in the Chernobyl Exclusion Zone and summarizes the pathways and strategy for handling the radioactive waste related problems in Ukraine and the Chernobyl Exclusion Zone, and in particular, the pathways and strategies stipulated by the National Radioactive Waste Management Program. The brief overview of the radioactive waste issues in the ChEZ presented in this article demonstrates that management of radioactive waste resulting from a beyond-designbasis accident at a nuclear power plant becomes the most challenging and the costliest effort during the mitigation and remediation activities. The costs of these activities are so high that the provision of radioactive waste final disposal facilities compliant with existing radiation safety requirements becomes an intolerable burden for the current generation of a single country, Ukraine. The nuclear accident at the Fukushima-1 NPP strongly indicates that accidents at nuclear sites may occur in any, even in a most technologically advanced country, and the Chernobyl experience shows that the scope of the radioactive waste management activities associated with the mitigation of such accidents may exceed the capabilities of a single country. Development of a special international program for broad international cooperation in accident related radioactive waste management activities is required to handle these issues. It would also be reasonable to consider establishment of a dedicated international fund for mitigation of accidents at nuclear sites, specifically, for handling radioactive waste problems in the ChEZ. The experience of handling Chernobyl radioactive waste management issues, including large volumes of radioactive soils and complex structures

  18. RADIOACTIVE WASTE MANAGEMENT IN THE CHERNOBYL EXCLUSION ZONE - 25 YEARS SINCE THE CHERNOBYL NUCLEAR POWER PLANT ACCIDENT

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E.; Jannik, T.

    2011-10-01

    Radioactive waste management is an important component of the Chernobyl Nuclear Power Plant accident mitigation and remediation activities of the so-called Chernobyl Exclusion Zone. This article describes the localization and characteristics of the radioactive waste present in the Chernobyl Exclusion Zone and summarizes the pathways and strategy for handling the radioactive waste related problems in Ukraine and the Chernobyl Exclusion Zone, and in particular, the pathways and strategies stipulated by the National Radioactive Waste Management Program. The brief overview of the radioactive waste issues in the ChEZ presented in this article demonstrates that management of radioactive waste resulting from a beyond-designbasis accident at a nuclear power plant becomes the most challenging and the costliest effort during the mitigation and remediation activities. The costs of these activities are so high that the provision of radioactive waste final disposal facilities compliant with existing radiation safety requirements becomes an intolerable burden for the current generation of a single country, Ukraine. The nuclear accident at the Fukushima-1 NPP strongly indicates that accidents at nuclear sites may occur in any, even in a most technologically advanced country, and the Chernobyl experience shows that the scope of the radioactive waste management activities associated with the mitigation of such accidents may exceed the capabilities of a single country. Development of a special international program for broad international cooperation in accident related radioactive waste management activities is required to handle these issues. It would also be reasonable to consider establishment of a dedicated international fund for mitigation of accidents at nuclear sites, specifically, for handling radioactive waste problems in the ChEZ. The experience of handling Chernobyl radioactive waste management issues, including large volumes of radioactive soils and complex structures

  19. Global risk of radioactive fallout after major nuclear reactor accidents

    OpenAIRE

    Lelieveld, J.; KUNKEL, D.; M. G. Lawrence

    2012-01-01

    Major reactor accidents of nuclear power plants are rare, yet the consequences are catastrophic. But what is meant by "rare"? And what can be learned from the Chernobyl and Fukushima incidents? Here we assess the cumulative, global risk of exposure to radioactivity due to atmospheric dispersion of gases and particles following severe nuclear accidents (the most severe ones on the International Nuclear Event Scale, INES 7), using particulate 137Cs and gaseous ...

  20. Health hazards from radiocaesium following the Chernobyl nuclear accident

    International Nuclear Information System (INIS)

    The WHO Regional Office for Europe has organized a series of meetings to assess the health impact of the Chernobyl nuclear accident. Considering the long-term importance of radiocaesium a decision was made to examine carefully the following aspects of this radionuclide in Europe: rate of deposition; environmental pathways through soil, flora and fauna to humans; absorption, distribution, metabolism, and excretion in humans; estimated doses resulting from these exposures; and some consideration of the possible adverse health effects. This is a report from a working group studying the health implications of radiocaesium. Refs, figs and tabs

  1. Radiological consequence of Chernobyl nuclear power accident in Japan

    International Nuclear Information System (INIS)

    Two years have elapsed since the accident in Chernobyl nuclear power station shocked those concerned with nuclear power generation. The effect that this accident exerted on human environment has still continued directly and indirectly, and the reports on the effect have been made in various countries and by international organizations. In Japan, about the exposure dose of Japanese people due to this accident, the Nuclear Safety Commission and Japan Atomic Energy Research Institute issued the reports. In this report, the available data concerning the envrionmental radioactivity level in Japan due to the Chernobyl accident are collected, and the evaluation of exposure dose which seems most appropriate from the present day scientific viewpoint was attempted by the detailed analysis in the National Institute of Radiological Sciences. The enormous number of the data observed in various parts of Japan were different in sampling, locality, time and measuring method, so difficulty arose frequently. The maximum concentration of I-131 in floating dust was 2.5 Bq/m3 observed in Fukui, and the same kinds of radioactive nuclides as those in Europe were detected. (Kako, I.)

  2. Report on the accident at the Chernobyl Nuclear Power Station

    International Nuclear Information System (INIS)

    This report presents the compilation of information obtained by various organizations regarding the accident (and the consequences of the accident) that occurred at Unit 4 of the nuclear power station at Chernobyl in the USSR on April 26, 1986. Each organization has independently accepted responsibility for one or more chapters. The specific responsibility of each organization is indicated. The various authors are identified in a footnote to each chapter. Very briefly the other chapters cover: the design of the Chernobyl nuclear station Unit 4; safety analyses for Unit 4; the accident scenario; the role of the operator; an assessment of the radioactive release, dispersion, and transport; the activities associated with emergency actions; and information on the health and environmental consequences from the accident. These subjects cover the major aspects of the accident that have the potential to present new information and lessons for the nuclear industry in general. The task of evaluating the information obtained in these various areas and the assessment of the potential implications has been left to each organization to pursue according to the relevance of the subject to their organization. Those findings will be issued separately by the cognizant organizations. The basic purpose of this report is to provide the information upon which such assessments can be made

  3. Reactors. Nuclear propulsion ships

    International Nuclear Information System (INIS)

    This article has for object the development of nuclear-powered ships and the conception of the nuclear-powered ship. The technology of the naval propulsion P.W.R. type reactor is described in the article B.N.3 141 'Nuclear Boilers ships'. (N.C.)

  4. Nuclear reactor repairing device

    International Nuclear Information System (INIS)

    Purpose: To enable free repairing of an arbitrary position in an LMFBR reactor. Constitution: A laser light emitted from a laser oscillator installed out of a nuclear reactor is guided into a portion to be repaired in the reactor by using a reflecting mirror, thereby welding or cutting it. The guidance of the laser out of the reactor into the reactor is performed by an extension tube depending into a through hole of a rotary plug, and the guidance of the laser light into a portion to be repaired is performed by the transmitting and condensing action of the reflecting mirror. (Kamimura, M.)

  5. Nuclear reactor physics course for reactor operators

    International Nuclear Information System (INIS)

    The education and training of nuclear reactor operators is important to guarantee the safe operation of present and future nuclear reactors. Therefore, a course on basic 'Nuclear reactor physics' in the initial and continuous training of reactor operators has proven to be indispensable. In most countries, such training also results from the direct request from the safety authorities to assure the high level of competence of the staff in nuclear reactors. The aim of the basic course on 'Nuclear Reactor Physics for reactor operators' is to provide the reactor operators with a basic understanding of the main concepts relevant to nuclear reactors. Seen the education level of the participants, mathematical derivations are simplified and reduced to a minimum, but not completely eliminated

  6. Special lecture on nuclear reactor

    International Nuclear Information System (INIS)

    This book gives a special lecture on nuclear reactor, which is divided into two parts. The first part has explanation on nuclear design of nuclear reactor and analysis of core with theories of integral transports, diffusion Nodal, transports Nodal and Monte Carlo skill parallel computer and nuclear calculation and speciality of transmutation reactor. The second part deals with speciality of nuclear reactor and control with nonlinear stabilization of nuclear reactor, nonlinear control of nuclear reactor, neural network and control of nuclear reactor, control theory of observer and analysis method of Adomian.

  7. Nuclear reactor simulator

    International Nuclear Information System (INIS)

    The Nuclear Reactor Simulator was projected to help the basic training in the formation of the Nuclear Power Plants operators. It gives the trainee the opportunity to see the nuclear reactor dynamics. It's specially indicated to be used as the support tool to NPPT (Nuclear Power Preparatory Training) from NUS Corporation. The software was developed to Intel platform (80 x 86, Pentium and compatible ones) working under the Windows operational system from Microsoft. The program language used in development was Object Pascal and the compiler used was Delphi from Borland. During the development, computer algorithms were used, based in numeric methods, to the resolution of the differential equations involved in the process. (author)

  8. Consequences of the nuclear power plant accident at Chernobyl

    International Nuclear Information System (INIS)

    The Chernobyl Nuclear Power Plant accident, in the Ukrainian Soviet Socialist Republic (SSR), on April 26, 1986, was the first major nuclear power plant accident that resulted in a large-scale fire and subsequent explosions, immediate and delayed deaths of plant operators and emergency service workers, and the radioactive contamination of a significant land area. The release of radioactive material, over a 10-day period, resulted in millions of Soviets, and other Europeans, being exposed to measurable levels of radioactive fallout. Because of the effects of wind and rain, the radioactive nuclide fallout distribution patterns are not well defined, though they appear to be focused in three contiguous Soviet Republics: the Ukrainian SSR, the Byelorussian SSR, and the Russian Soviet Federated Socialist Republic. Further, because of the many radioactive nuclides (krypton, xenon, cesium, iodine, strontium, plutonium) released by the prolonged fires at Chernobyl, the long-term medical, psychological, social, and economic effects will require careful and prolonged study. Specifically, studies on the medical (leukemia, cancers, thyroid disease) and psychological (reactive depressions, post-traumatic stress disorders, family disorganization) consequences of continued low dose radiation exposure in the affected villages and towns need to be conducted so that a coherent, comprehensive, community-oriented plan may evolve that will not cause those already affected any additional harm and confusion

  9. Chernobyl nuclear accident: Effects on food. April 1986-November 1989 (Citations from the Food Science and Technology Abstracts data base). Report for April 1986-November 1989

    International Nuclear Information System (INIS)

    This bibliography contains citations concerning studies and measurements of the radioactive contamination by the Chernobyl nuclear reactor accident of food and the food chain. The studies cover meat and dairy products, vegetables, fish, food chains, and radioactive contamination of agricultural farms and lands. (This updated bibliography contains 108 citations, 43 of which are new entries to the previous edition.)

  10. Chernobyl nuclear accident: effects on foods. April 1986-October 1988 (Citations from the Food Science and Technology Abstracts data base). Report for April 1986-October 1988

    International Nuclear Information System (INIS)

    This bibliography contains citations concerning studies and measurements of the radioactive contamination of the Chernobyl nuclear reactor accident of food and food chains. The studies cover meat and dairy products, vegetables, fish, food chains, and radioactive contamination of agricultural farms and lands. (Contains 65 citations fully indexed and including a title list.)

  11. Global risk of radioactive fallout after nuclear reactor accidents

    OpenAIRE

    Lelieveld, J.; KUNKEL, D.; M. G. Lawrence

    2011-01-01

    Reactor core meltdowns of nuclear power plants are rare, yet the consequences are catastrophic. But what is meant by "rare"? And what can be learned from the Chernobyl and Fukushima incidents? Here we assess the risk of exposure to radioactivity due to atmospheric dispersion of gases and particles following severe nuclear accidents, using particulate 137Cs and gaseous 131I as proxies for the fallout. It appears that previously the occurrence of ma...

  12. Comparison of the Chernobyl and Fukushima nuclear accidents: A review of the environmental impacts

    Energy Technology Data Exchange (ETDEWEB)

    Steinhauser, Georg, E-mail: georg.steinhauser@colostate.edu; Brandl, Alexander; Johnson, Thomas E.

    2014-02-01

    The environmental impacts of the nuclear accidents of Chernobyl and Fukushima are compared. In almost every respect, the consequences of the Chernobyl accident clearly exceeded those of the Fukushima accident. In both accidents, most of the radioactivity released was due to volatile radionuclides (noble gases, iodine, cesium, tellurium). However, the amount of refractory elements (including actinides) emitted in the course of the Chernobyl accident was approximately four orders of magnitude higher than during the Fukushima accident. For Chernobyl, a total release of 5300 PBq (excluding noble gases) has been established as the most cited source term. For Fukushima, we estimated a total source term of 520 (340–800) PBq. In the course of the Fukushima accident, the majority of the radionuclides (more than 80%) was transported offshore and deposited in the Pacific Ocean. Monitoring campaigns after both accidents reveal that the environmental impact of the Chernobyl accident was much greater than of the Fukushima accident. Both the highly contaminated areas and the evacuated areas are smaller around Fukushima and the projected health effects in Japan are significantly lower than after the Chernobyl accident. This is mainly due to the fact that food safety campaigns and evacuations worked quickly and efficiently after the Fukushima accident. In contrast to Chernobyl, no fatalities due to acute radiation effects occurred in Fukushima. - Highlights: • The environmental effects of Chernobyl and Fukushima are compared. • Releases of radionuclides from Chernobyl exceeded Fukushima by an order of magnitude. • Chernobyl caused more severe radiation-related health effects. • Overall, Chernobyl was a much more severe nuclear accident than Fukushima. • Psychological effects are neglected but important consequences of nuclear accidents.

  13. Chernobyl and status of nuclear power development in the USSR

    International Nuclear Information System (INIS)

    The Chernobyl accident has seriously affected development of the USSR nuclear power program. But it has not eliminated the basic prerequisites for nuclear power development in the USSR which are: - resources and consumption territorial disproportions; - large share of oil and gas in electricity generation; - negative ecological aspects of coal plants; - high power industry development rate. At the same time it has aggravated the old problems and has given rise to some new-ones of which the most important are: - increased safety requirements; rise in costs; longer construction schedules; public opinion. On the whole for further safe development of nuclear power a detailed analysis of the Chernobyl accident is required, including studies of long-term accident consequences and measures of their mitigation and elimination. A necessary condition for NPP operation to be continued would also be development and rapid implementation of technical approaches which would permit to eliminate the design shortcomings in the RBMK NPPs both operating and those under construction. At the same time we have to ensure their competitiveness with other energy sources and possibility of expansion of their applications. The problem of public opinion should be emphasised. After the Chernobyl accident we have faced a social phenomenon which is quite new in this country. There is almost no site where the population was not opposed to NPP construction. For us these problems are especially difficult as we have had no experience of this kind of interactions with the public. We are planning and begin to realize a program basing on the current world experience. This program includes primarily a wide series of publications on the problems of nuclear energy its ecologic and economic advantages as compared with conventional and alternative energy sources,, using all cur-rent media. Centers of public information discussion clubs, exhibitions etc are being organized. In particular, our Institute has

  14. Nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    A nuclear reactor fuel element comprising a column of vibration compacted fuel which is retained in consolidated condition by a thimble shaped plug. The plug is wedged into gripping engagement with the wall of the sheath by a wedge. The wedge material has a lower coefficient of expansion than the sheath material so that at reactor operating temperature the retainer can relax sufficient to accommodate thermal expansion of the column of fuel. (author)

  15. Nuclear reactor design

    CERN Document Server

    2014-01-01

    This book focuses on core design and methods for design and analysis. It is based on advances made in nuclear power utilization and computational methods over the past 40 years, covering core design of boiling water reactors and pressurized water reactors, as well as fast reactors and high-temperature gas-cooled reactors. The objectives of this book are to help graduate and advanced undergraduate students to understand core design and analysis, and to serve as a background reference for engineers actively working in light water reactors. Methodologies for core design and analysis, together with physical descriptions, are emphasized. The book also covers coupled thermal hydraulic core calculations, plant dynamics, and safety analysis, allowing readers to understand core design in relation to plant control and safety.

  16. Papers submitted to the international forum ''one decade after Chernobyl: nuclear safety aspects''. Working material

    International Nuclear Information System (INIS)

    The objective of the forum is to review the remedial measures taken since the Chernobyl accident for improving the safety of RBMK reactors and the Chernobyl containment structure (sarcophagus). The forum will also serve to exchange information on national, bilateral and multilateral efforts for the enhancement of RBMK safety. The conclusions and recommendations will serve as a basis for a background paper to be prepared for presentation, by the forum chairman, at the International Conference ''One decade after Chernobyl'' to held in Vienna from 8-12 April 1996. Refs, figs, tabs

  17. Nuclear rocket engine reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lanin, Anatoly

    2013-07-01

    Covers a new technology of nuclear reactors and the related materials aspects. Integrates physics, materials science and engineering Serves as a basic book for nuclear engineers and nuclear physicists. The development of a nuclear rocket engine reactor (NRER) is presented in this book. The working capacity of an active zone NRER under mechanical and thermal load, intensive neutron fluxes, high energy generation (up to 30 MBT/l) in a working medium (hydrogen) at temperatures up to 3100 K is displayed. Design principles and bearing capacity of reactors area discussed on the basis of simulation experiments and test data of a prototype reactor. Property data of dense constructional, porous thermal insulating and fuel materials like carbide and uranium carbide compounds in the temperatures interval 300 - 3000 K are presented. Technological aspects of strength and thermal strength resistance of materials are considered. The design procedure of possible emergency processes in the NRER is developed and risks for their origination are evaluated. Prospects of the NRER development for pilotless space devices and piloted interplanetary ships are viewed.

  18. Nuclear Reactors and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Cason, D.L.; Hicks, S.C. [eds.

    1992-01-01

    This publication Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency`s Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on the Energy Science and Technology Database and Nuclear Science Abstracts (NSA) database. Current information, added daily to the Energy Science and Technology Database, is available to DOE and its contractors through the DOE Integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user`s needs.

  19. The accident at the Chernobyl' nuclear power plant and its consequences. Pt. 1. General material

    International Nuclear Information System (INIS)

    The report contains a presentation of the Chernobyl' nuclear power station and of the RBMK-1000 reactor, including its principal physical characteristics, the safety systems and a description of the site and of the surrounding region. After a chronological account of the events which led to the accident and an analysis of the accident using a mathematical model it is concluded that the prime cause of the accident was an extremely improbable combination of violations of instructions and operating rules committed by the staff of the unit. Technical and organizational measures for improving the safety of nuclear power plants with RBMK reactors have been taken. A detailed description of the actions taken to contain the accident and to alleviate its consequences is given and includes the fire fighting at the nuclear power station, the evaluation of the state of the fuel after the accident, the actions taken to limit the consequences of the accident in the core, the measures taken at units 1, 2 and 3 of the nuclear power station, the monitoring and diagnosis of the state of the damaged unit, the decontamination of the site and of the 30 km zone and the long-term entombment of the damaged unit. The measures taken for environmental radioactive contamination monitoring, starting by the assessment of the quantity, composition and dynamics of fission products release from the damaged reactor are described, including the main characteristics of the radioactive contamination of the atmosphere and of the ground, the possible ecological consequences and data on the exposure of plant and emergency service personnel and of the population in the 30 km zone around the plant. The last part of the report presents some recommendations for improving nuclear power safety, including scientific, technical and organizational aspects and international measures. Finally, an overview of the development of nuclear power in the USSR is given

  20. Chernobyl, 13 years after

    International Nuclear Information System (INIS)

    This is an annual report, regularly issued by IPSN, that presents the ecological and health consequences of the Chernobyl Nuclear Accident. The present status of the Chernobyl Nuclear Plant, which Ukraine engaged to stop definitively in year 2000, is summarized. The only reactor unit now in operation is Chernobylsk-3 Reactor which poses two safety questions: evolution of cracks in part of the tubing and behaviour of the pressure tubes. Although, some improvements in the RBMK reactor types were introduced, problems remain that make IPSN to stress the requirement of stopping this NPP completely. In the contaminated territories surrounding Chernobyl incidence rate of infant thyroid cancers continues to grow, reaching values 10 to 100 times higher than the natural rate. In France the IPSN analyzed 60,000 records carried out in 17 sites during May 1986 and April 1989. It was estimated that the individual dose received during 60 years (1986-2046) by the inhabitants of the most affected zone (eastern France) is lower than 1.5 mSv, a value lower than 1% of the natural cosmic and telluric radioactivity exposure for the same period. For the persons assumed to live in the most attacked forests (from eastern France) and nourishing daily with venison and mushrooms the highest estimate is 1 mSv a year. Concerning the 'hot spots', identified in mountains by IPSN and CRIIRAD, the doses received by excursionists are around 0.015 mSv. For an average inhabitant of the country the dose piled up in the thyroid due to iodine-131 fallout is estimated to 0.5-2 mSv for an adult and 6.5-16 mSv for an infant. These doses are 100 to 1000 times lower than the ones to which the infants living in the neighbourhood of Chernobyl are exposed to. The contents of the report is displayed in the following six chapters: 1. Chernobyl in some figures; 2. The 'sarcophagus' and the reactors of the Chernobyl NPP; 3. Health consequences of the Chernobyl accident;. 4. The impact of Chernobyl fallout in France

  1. Nuclear safety cooperation for Soviet designed reactors

    International Nuclear Information System (INIS)

    The nuclear accident at the Chernobyl nuclear power plant in 1986 first alerted the West to the significant safety risks of Soviet designed reactors. Five years later, this concern was reaffirmed when the IAEA, as a result of a review by an international team of nuclear safety experts, announced that it did not believe the Kozloduy nuclear power plants in Bulgaria could be operated safely. To address these safety concerns, the G-7 summit in Munich in July 1992 outlined a five point program to address the safety problems of Soviet Designed Reactors: operational safety improvement; near-term technical improvements to plants based on safety assessment; enhancing regulatory regimes; examination of the scope for replacing less safe plants by the development of alternative energy sources and the more efficient use of energy; and upgrading of the plants of more recent design. As of early 1994, over 20 countries and international organizations have pledged hundreds of millions of dollars in financial assistance to improve safety. This paper summarizes these assistance efforts for Soviet designed reactors, draws lessons learned from these activities, and offers some options for better addressing these concerns

  2. Nuclear reactor constructions

    International Nuclear Information System (INIS)

    A nuclear reactor construction comprising a reactor core submerged in a pool of liquid metal coolant in a primary vessel which is suspended from the roof structure of a containment vault. Control rods supported from the roof structure are insertable in the core which is carried on a support structure from the wall of the primary vessel. To prevent excessive relaxation of the support structure whereby the control rods would be displaced relative to the core, the support structure incorporates a normally inactive secondary structure designed to become effective in bracing the primary structure against further relaxation beyond a predetermined limit. (author)

  3. Nuclear Rocket Engine Reactor

    CERN Document Server

    Lanin, Anatoly

    2013-01-01

    The development of a nuclear rocket engine reactor (NRER ) is presented in this book. The working capacity of an active zone NRER under mechanical and thermal load, intensive neutron fluxes, high energy generation (up to 30 MBT/l) in a working medium (hydrogen) at temperatures up to 3100 K is displayed. Design principles and bearing capacity of reactors area discussed on the basis of simulation experiments and test data of a prototype reactor. Property data of dense constructional, porous thermal insulating and fuel materials like carbide and uranium carbide compounds in the temperatures interval 300 - 3000 K are presented. Technological aspects of strength and thermal strength resistance of materials are considered. The design procedure of possible emergency processes in the NRER is developed and risks for their origination are evaluated. Prospects of the NRER development for pilotless space devices and piloted interplanetary ships are viewed.

  4. Nuclear power reactor physics

    International Nuclear Information System (INIS)

    The purpose of this book is to explain the physical working conditions of nuclear reactors for the benefit of non-specialized engineers and engineering students. One of the leading ideas of this course is to distinguish between two fundamentally different concepts: - a science which could be called neutrodynamics (as distinct from neutron physics which covers the knowledge of the neutron considered as an elementary particle and the study of its interactions with nuclei); the aim of this science is to study the interaction of the neutron gas with real material media; the introduction will however be restricted to its simplified expression, the theory and equation of diffusion; - a special application: reactor physics, which is introduced when the diffusing and absorbing material medium is also multiplying. For this reason the chapter on fission is used to introduce this section. In practice the section on reactor physics is much longer than that devoted to neutrodynamics and it is developed in what seemed to be the most relevant direction: nuclear power reactors. Every effort was made to meet the following three requirements: to define the physical bases of neutron interaction with different materials, to give a correct mathematical treatment within the limit of necessary simplifying hypotheses clearly explained; to propose, whenever possible, numerical applications in order to fix orders of magnitude

  5. Chernobyl, 14 years later

    International Nuclear Information System (INIS)

    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

  6. Environmental problems associated with decommissioning the Chernobyl Nuclear Power Plant Cooling Pond.

    Science.gov (United States)

    Oskolkov, B Ya; Bondarkov, M D; Gaschak, S P; Maksymenko, A M; Maksymenko, V M; Martynenko, V I; Farfán, E B; Jannik, G T; Marra, J C

    2010-11-01

    Decommissioning of nuclear power plants and other nuclear fuel cycle facilities associated with residual radioactive contamination of their territories is an imperative issue. Significant problems may result from decommissioning of cooling ponds with residual radioactive contamination. The Chernobyl Nuclear Power Plant (ChNPP) Cooling Pond is one of the largest self-contained water reservoirs in the Chernobyl region and Ukrainian and Belorussian Polesye region. The 1986 ChNPP Reactor Unit Number Four significantly contaminated the ChNPP Cooling Pond. The total radionuclide inventory in the ChNPP Cooling Pond bottom deposits are as follows: ¹³⁷Cs: 16.28 ± 2.59 TBq; ⁹⁰Sr: 2.4 ± 0.48 TBq; and ²³⁹+²⁴⁰Pu: 0.00518 ± 0.00148 TBq. The ChNPP Cooling Pond is inhabited by over 500 algae species and subspecies, over 200 invertebrate species, and 36 fish species. The total mass of the living organisms in the ChNPP Cooling Pond is estimated to range from about 60,000 to 100,000 tons. The territory adjacent to the ChNPP Cooling Pond attracts many birds and mammals (178 bird species and 47 mammal species were recorded in the Chernobyl Exclusion Zone). This article describes several options for the ChNPP Cooling Pond decommissioning and environmental problems associated with its decommissioning. The article also provides assessments of the existing and potential exposure doses for the shoreline biota. For the 2008 conditions, the estimated total dose rate values were 11.4 40 μGy h⁻¹ for amphibians, 6.3 μGy h⁻¹ for birds, 15.1 μGy h⁻¹ for mammals, and 10.3 μGy h⁻¹ for reptiles, with the recommended maximum dose rate being equal to 40 μGy h⁻¹. However, drying the ChNPP Cooling Pond may increase the exposure doses to 94.5 μGy h⁻¹ for amphibians, 95.2 μGy h⁻¹ for birds, 284.0 μGy h⁻¹ for mammals, and 847.0 μGy h⁻¹ for reptiles. All of these anticipated dose rates exceed the recommended values. PMID:20938234

  7. Bone marrow transplantation after the Chernobyl nuclear accident

    International Nuclear Information System (INIS)

    On April 26, 1986, an accident at the Chernobyl nuclear power station in the Soviet Union exposed about 200 people to large doses of total-body radiation. Thirteen persons exposed to estimated total-body doses of 5.6 to 13.4 Gy received bone marrow transplants. Two transplant recipients, who received estimated doses of radiation of 5.6 and 8.7 Gy, are alive more than three years after the accident. The others died of various causes, including burns (the cause of death in five), interstitial pneumonitis (three), graft-versus-host disease (two), and acute renal failure and adult respiratory distress syndrome (one). There was hematopoietic (granulocytic) recovery in nine transplant recipients who could be evaluated, six of whom had transient partial engraftment before the recovery of their own marrow. Graft-versus-host disease was diagnosed clinically in four persons and suspected in two others. Although the recovery of endogenous hematopoiesis may occur after exposure to radiation doses of 5.6 to 13.4 Gy, we do not know whether it is more likely after the transient engraftment of transplanted stem cells. Because large doses of radiation affect multiple systems, bone marrow recovery does not necessarily ensure survival. Furthermore, the risk of graft-versus-host disease must be considered when the benefits of this treatment are being weighed

  8. Measures taken to improve the safety of nuclear power plants in the USSR after the Chernobyl accident

    International Nuclear Information System (INIS)

    The Soviet delegation to the IAEA experts' meeting (August 25-29, 1986) presented information on the Chernobyl Nuclear Power Plant accident and its consequences. Using data obtained through August 1, 1986, this information contained the results of an investigation into the causes of the accident as well as a description and preliminary analysis of the effectiveness of the immediate steps taken to limit and eliminate its consequences. Subsequent efforts were channeled in the following directions: (1) Continuing operations to eliminate the accident's consequences including: (a) completing the design and construction of a protective cover (sarcophagus) to reliably protect the environment from radioactivity and the introduction of radioactive matter from the destroyed unit; (b) further decontamination of the Chernobyl Nuclear Power Plant site and inhabited areas within the affected zone; and (c) carrying out required sanitary and medical measures to ensure the safety of the population and to protect their health. (2) Development and implementation of longitudinal studies of the long-term consequences of the accident. (3) Development of introduction of measures to increase the safety of working nuclear power stations. (4) Examination of plans for the future development of the nuclear power industry and prospects for increasing its safety level, including: conceptual development of a new generation of nuclear reactors; and expansion of scientific investigation into all aspects of safety assessment and safety assurance in the nuclear power industry. The present report examines the progress of studies along these lines and the conclusions which have been drawn

  9. Nuclear research reactors in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Cota, Anna Paula Leite; Mesquita, Amir Zacarias, E-mail: aplc@cdtn.b, E-mail: amir@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    The rising concerns about global warming and energy security have spurred a revival of interest in nuclear energy, giving birth to a 'nuclear power renaissance' in several countries in the world. Particularly in Brazil, in the recent years, the nuclear power renaissance can be seen in the actions that comprise its nuclear program, summarily the increase of the investments in nuclear research institutes and the government target to design and build the Brazilian Multipurpose research Reactor (BMR). In the last 50 years, Brazilian research reactors have been used for training, for producing radioisotopes to meet demands in industry and nuclear medicine, for miscellaneous irradiation services and for academic research. Moreover, the research reactors are used as laboratories to develop technologies in power reactors, which are evaluated today at around 450 worldwide. In this application, those reactors become more viable in relation to power reactors by the lowest cost, by the operation at low temperatures and, furthermore, by lower demand for nuclear fuel. In Brazil, four research reactors were installed: the IEA-R1 and the MB-01 reactors, both at the Instituto de Pesquisas Energeticas Nucleares (IPEN, Sao Paulo); the Argonauta, at the Instituto de Engenharia Nuclear (IEN, Rio de Janeiro) and the IPR-R1 TRIGA reactor, at the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN, Belo Horizonte). The present paper intends to enumerate the characteristics of these reactors, their utilization and current academic research. Therefore, through this paper, we intend to collaborate on the BMR project. (author)

  10. Health status and follow-up of the Chernobyl Nuclear Power Plant accident liquidators in Latvia

    International Nuclear Information System (INIS)

    The accident at the Nuclear Power Plant in Chernobyl create a new problem for health professionals in Latvia due to the fact that 6475 inhabitants (mainly healthy and men of reproductive age) of Latvia took part in clear-up works in Chernobyl within the period 1986-1991. Chernobyl clear-up workers were exposed γ-radiation and they also incorporated radionuclides. The doses documented for the clear-up workers are variable; they are estimated to be between 0.01-0.5 Gy although the specialists working on the precision of received doses think that they could be even 2 or 3 times higher. The aim of this work is to evaluate the health status of liquidators investigating them on a long-term basis: to create the correct system of health status evaluation of Chernobyl clear-up workers, to improve the register of Chernobyl clear-up workers and of their children, to analyze the data about the incidence of different diseases and mortality gained from follow-ups, to evaluate health status and clinical picture within the period of time, to work out and use adequate methods of treatment. Chernobyl clear-up workers more often than the control group suffer from diseases of the nervous, the endocrine and the metabolic and immune system. They also have higher rate of incidence for diseases of digestive and respiratory system and for diseases of bones, muscles and connective tissue higher rates of accidents and suicides. Now, ten years after the accident there are Chernobyl clear-up workers who are chronically ill and their health status is expected to be worse in the next few years. Regular follow-up and medical examination of Chernobyl clear-up workers and their children should be carried out every year. Regular rehabilitation of Chernobyl clear-up workers should be provided by the government

  11. Towards nuclear fusion reactors

    International Nuclear Information System (INIS)

    In the middle of 21st century, the population on the earth is expected to double, and the energy that mankind consumes to triple. The nuclear fusion which is said the ultimate energy source for mankind is expected to solve this energy problem. As for fusion reactors, fuel materials exist inexhaustibly, distributing evenly, they have high safety in principle, the product of burning is harmless nonradioactive substance that does not require the treatment and disposal, and the attenuation of induced radioactivity due to neutrons is quick and the effect to global environment is little. The basic plan of second stage nuclear fusion research and development was decided in 1975, aiming at attaining the critical plasma condition. JT-60 has attained it in 1987. The project of international thermonuclear fusion experimental reactor (ITER) was started, and the conceptual design was carried out. Under such background, the third stage basic plan was decided in 1992, and its objective is self ignition condition, long time burning and the basis of the reactor engineering technology. The engineering design of the ITER is investigated. (K.I.)

  12. Nuclear reactor building

    Science.gov (United States)

    Gou, Perng-Fei; Townsend, Harold E.; Barbanti, Giancarlo

    1994-01-01

    A reactor building for enclosing a nuclear reactor includes a containment vessel having a wetwell disposed therein. The wetwell includes inner and outer walls, a floor, and a roof defining a wetwell pool and a suppression chamber disposed thereabove. The wetwell and containment vessel define a drywell surrounding the reactor. A plurality of vents are disposed in the wetwell pool in flow communication with the drywell for channeling into the wetwell pool steam released in the drywell from the reactor during a LOCA for example, for condensing the steam. A shell is disposed inside the wetwell and extends into the wetwell pool to define a dry gap devoid of wetwell water and disposed in flow communication with the suppression chamber. In a preferred embodiment, the wetwell roof is in the form of a slab disposed on spaced apart support beams which define therebetween an auxiliary chamber. The dry gap, and additionally the auxiliary chamber, provide increased volume to the suppression chamber for improving pressure margin.

  13. Health consequences of Chernobyl. 25 years after the reactor catastrophy; Gesundheitliche Folgen von Tschernobyl. 25 Jahre nach der Reaktorkatastrophe

    Energy Technology Data Exchange (ETDEWEB)

    Pflugbeil, Sebastian; Schmitz-Feuerhake, Inge [Gesellschaft fuer Strahlenschutz e.V., Berlin (Germany); Paulitz, Henrik; Claussen, Angelika [Internationale Aerzte fuer die Verhuetung des Atomkrieges, Aerzte in sozialer Verantwortung e.V. (IPPNW), Berlin (Germany). Deutsche Sektion

    2011-04-15

    The report is an evaluation of studies indicating health effects as a consequence of the reactor catastrophe in Chernobyl. The most exposed population include the cleaning personnel (liquidators), the population evacuated from the 30 km zone, the populations in highly contaminated regions in Russia, Belarus and Ukraine, the European population in lass contaminated regions. The following issues are discussed: the liquidators, infant mortality, genetic and teratogenic damages, thyroid carcinoma and other thyroid diseases, carcinogenic diseases and leukemia, other diseases following the Chernobyl catastrophe.

  14. The Chernobyl and Fukushima Daiichi nuclear accidents and their tragic consequences

    CERN Document Server

    CERN. Geneva

    2016-01-01

    On April 26, 1986, the Unit 4 of the RBMK nuclear power plant of Chernobyl, in Ukraine, went out of control during a test at low-power, leading to an explosion and fire. The reactor building was totally demolished and very large amounts of radiation were released into the atmosphere for several hundred kilometres around the site including the nearby town of Pripyat. The explosion leaving tons of nuclear waste and spent fuel residues without any protection and control totally contaminating the entire area. Several hundred thousand people were affected by the radiation fall out. The radioactive cloud spread across Europe affecting most of the Northern, Central and Eastern European countries. Some areas of southern Switzerland, of northern Italy as well as western France were subject to radioactive contamination. The initiative of the G7 countries to launch and important programme for the closure of some Soviet built nuclear plants was accepted by several donor countries. A team of engineers was established wi...

  15. A neutron monitoring system for evaluating nuclear safety at the Chernobyl Unit 4 fuel debris

    International Nuclear Information System (INIS)

    The remains of the nuclear fuel that was severely damaged in the 1986 Chernobyl unit 4 accident lie in large masses in the premises under the reactor. The fuel debris exists in the form of dusts, chunks, and lavas, and the quantities are substantial--some rooms contain several tons of fuel. Since there is a possibility of water entering these rooms, there is an obvious concern over criticality safety. Incidents of increased neutron count rates have been noted in the vicinity of nuclear fuel debris. Pacific Northwest National Laboratory (PNNL), under a program funded by the US Department of Energy, responded to this safety concern by assembling a new monitoring system to characterize the radiation environment in the vicinity of major fuel deposits. The new monitoring system will measure the gamma and neutron radiation fields in several locations. The measurement data can be tracked over time to determine the characteristics of the radiation fields and better understand the nuclear safety conditions in the vicinity of the fuel. The monitoring system was designed to provide information that will allow a better interpretation of any future events

  16. The Chernobyl reactor accident and its consequences. Informative report prepared on behalf of the IAEA meeting, Vienna, August 25-29, 1986. Pt. 1

    International Nuclear Information System (INIS)

    GRS has revised the German translation of part 1 of the report on the Chernobyl reactor accident. The translation is technically clear and intelligible and contains the current technical terms. The report comprises a description of RBMK-1000, a chronological description of the accident, the analysis of the accident, the causes of the accident, measures preventing the further development of the accident as well as measures controlling the radioactive contamination of the environment and the population. The report discusses immediate emergency measures improving the safety of RBMK-type nuclear power plants and deals with recommendations for nuclear safety engineering. (DG)

  17. Measurement in nuclear reactors

    International Nuclear Information System (INIS)

    A nuclear reactor construction has a flux detector comprising a bundle of fibre optics each having a bead incorporating a substance which scintillates on being struck by neutrons or gamma radiations. The other ends of the fibre optics terminate at an image intensifier. The optical fibres may be of glass made from a mixture of silica, alkaline earth metal oxide, cerous oxide and alkali metal oxide. The beads may be incorporated in a disc forming a detector head, which is in a protective guide tube, through which an inert gas may be passed. (author)

  18. Radiation monitoring during construction of the encapsulation for unit 4 of the Chernobyl Nuclear Power Plant

    International Nuclear Information System (INIS)

    The accident at the Chernobyl nuclear power plant caused high levels of surface contamination by radionuclides and gamma radiation exposure dose levels in excess of 400 R/h. Moreover, the radiation fields were uneven and inhomogeneous. This is due to the fact that, in addition to dispersed fuel, fragments of the reactor core were also ejected into the buildings and the area surrounding the Chernobyl nuclear power plant. The dosimetric monitoring section monitored the radiation situation. Both traditional and specially developed methods were used to monitor the radiation situation, enabling the measurement of radiation risk factors, the determination of space-angular distribution of gamma radiation, and the detection of local contamination sources. Radiation situation monitoring results show that 75-80% of the gamma radiation was coming from nuclear fuel in the plant compound and not 'streamings' from the wreck of the Unit 4 reactor. The area has been covered with a protective layer thus reducing the gamma radiation levels by 7-20 times. After the encapsulation had been erected, gamma radiation levels in the vicinity of Unit 4 decreased by a factor of approximately 100. The concentration of radioactive aerosols at the work sites while the encapsulation was under construction was, at most, ten times the permitted concentration (PCA), and only when certain operations were being performed which raised a lot of dust did it reach 100-300 PCA. Owing to the high levels of gamma radiation, the danger of external irradiation of personnel was significantly greater than the danger from internal irradiation. Therefore staff were monitored individually for gamma radiation. A permissible dose level of 25 R for the whole period of work (1-2 months) was implemented for the purpose of individual dosimetric monitoring, and a control level of 1 R per shift. The mean exposure dose received by personnel directly involved in the construction of the encapsulation was 8.6 R, and 50.6% of

  19. Virtual nuclear reactor for education of nuclear reactor physics

    International Nuclear Information System (INIS)

    As one of projects that were programmed in the cultivation program for human resources in nuclear engineering sponsored by the Ministry of Economy, Trade and Industry, the development of a virtual reactor for education of nuclear reactor physics started in 2007. The purpose of the virtual nuclear reactor is to make nuclear reactor physics easily understood with aid of visualization. In the first year of this project, the neutron slowing down process was visualized. The data needed for visualization are provided by Monte Carlo calculations; The flights of the respective neutrons generated by nuclear fissions are traced through a reactor core until they disappear by neutron absorption or slow down to a thermal energy. With this visualization and an attached supplement textbook, it is expected that the learners can learn more clearly the physical implication of neutron slowing process that is mathematically described by the Boltzmann neutron transport equation. (author)

  20. Chernobyl: four years later: attitudes, risk management and communication

    NARCIS (Netherlands)

    J. van der Pligt; C.H.J. Midden

    1990-01-01

    Discusses the impact that the nuclear reactor accident at Chernobyl has had on risk management and risk communication in relation to risk perception; decisions and coping with uncertainty; and public opinion, personal attitudes, and public policy.

  1. Chernobyl, 17 after

    International Nuclear Information System (INIS)

    This information document takes stock on the Chernobyl accident effects, 17 years after the reactor accident. The domains concerned are: the Chernobyl power plant, the sanitary consequences of the accident in the most exposed countries, the Chernobyl environment and the polluted regions management, the Chernobyl accident consequences in France; Some data and technical sheets on the RBMK reactors and the international cooperation are also provided. (A.L.B.)

  2. Optimal control of nuclear reactors

    International Nuclear Information System (INIS)

    The modern control theory is applied to the design of control systems for experimental nuclear reactors that do not belong to power reactors, the component forms of optimal control systems for nuclear reactors are demonstrated. The adoption of output quadratic integral criterion and incomplete state feedback technique can make these systems both efficient and economical. Moreover, approximate handling methods are given so as to simplify the calculations in design. In addition, the adoptable reference values of parameters are given in the illustration

  3. Nuclear reactor spacer assembly

    International Nuclear Information System (INIS)

    A fuel assembly for a nuclear reactor is disclosed wherein the fuel element receiving and supporting grid is comprised of a first metal, the guide tubes which pass through the grid assembly are comprised of a second metal and the grid is supported on the guide tubes by means of expanded sleeves located intermediate the grid and guide tubes. The fuel assembly is fabricated by inserting the sleeves, of initial outer diameter commensurate with the guide tube outer diameters, through the holes in the grid assembly provided for the guide tubes and thereafter expanding the sleeves radially outwardly along their entire length such that the guide tubes can subsequently be passed through the sleeves. The step of radial expansion, as a result of windows provided in the sleeves having dimensions commensurate with the geometry of the grid, mechanically captures the grid and simultaneously preloads the sleeve against the grid whereby relative motion between the grid and guide tube will be precluded

  4. Nuclear reactor measurement system

    International Nuclear Information System (INIS)

    An instrument to detect the temperature and flow-rate of the liquid metal current of a coolant fluid sample from adjacent sub-assemblies of a liquid metal-cooled nuclear reactor is described. It includes three thermocouple hot junctions mounted in series, each intended for exposure to a sample-current from a single sub-assembly, electromagnetic coils being mounted around an induction core which detects variations in the liquid metal flow-rate by deformation of the lines of flux. The instrument may also include a thermocouple to detect the mean temperature of the sample-current of coolant fluid from several sources, the result being that the temperature of the coolant fluid current in a sub-assembly may be inferred from the three temperature readings associated with this sub-assembly

  5. 30 years life with Chernobyl, 5 years life with Fukushima. Health consequences of the nuclear catastrophes of Chernobyl and Fukushima; 30 Jahre Leben mit Tschernobyl, 5 Jahre Leben mit Fukushima. Gesundheitliche Folgen der Atomkatastrophen von Tschernobyl und Fukushima

    Energy Technology Data Exchange (ETDEWEB)

    Claussen, Angelika; Rosen, Alex

    2016-02-15

    The IPPNW report on health consequences of the nuclear catastrophes of Chernobyl and Fukushima covers the following issues: Part.: 30 years life with Chernobyl: Summarized consequences of Chernobyl, the accident progression, basic data of the catastrophe, estimation of health hazards as a consequence of the severe accident of Chernobyl, health consequences for the liquidators, health consequences for the contaminated population, mutagenic and teratogenic effects. Part B: 5 years life with Fukushima: The start of the nuclear catastrophe, emissions and contamination, consequences of the nuclear catastrophe on human health, thyroid surveys in the prefecture Fukushima, consequences of the nuclear catastrophe on the ecosystem, outlook.

  6. Fast reactors and nuclear nonproliferation

    International Nuclear Information System (INIS)

    Problems are discussed with regard to nuclear fuel cycle resistance in fast reactors to nuclear proliferation risk due to the potential for use in military programs of the knowledge, technologies and materials gained from peaceful nuclear power applications. Advantages are addressed for fast reactors in the creation of a more reliable mode of nonproliferation in the closed nuclear fuel cycle in comparison with the existing fully open and partially closed fuel cycles of thermal reactors. Advantages and shortcomings are also discussed from the point of view of nonproliferation from the start with fast reactors using plutonium of thermal reactor spent fuel and enriched uranium fuel to the gradual transition using their own plutonium as fuel. (author)

  7. Chernobyl nuclear accident revealed from the 7010 m Muztagata ice core record

    Institute of Scientific and Technical Information of China (English)

    TIAN LiDe; YAO TanDong; WU GuangJian; LI Zhen; XU BaiQing; LI YueFang

    2007-01-01

    The total activity variation with depth from a 41.6 m Muztagata ice core drilled at 7010 m,recorded not only the 1963 radioactive layer due to the thermonuclear test,but also clearly the radioactive peak released by the Chernobyl accident in 1986.This finding indicates that the Chernobyl nuclear accident was clearly recorded in alpine glaciers in the Pamirs of west China,and the layer can be potentially used for ice core dating in other high alpine glaciers in the surrounding regions.

  8. Scientific recommendations for the reconstruction of radiation doses due to the reactor accident at Chernobyl

    International Nuclear Information System (INIS)

    In the years after the Chernobyl reactor accident, many studies of the radiation exposure levels and resulting health effects in the countries of the CIS have been conducted. The increasing incidence of childhood thyroid cancers in Belarus and Ukraine has stimulated worldwide multi- and bilateral cooperations with those countries and Russia in order to optimize benefits for those directly affected, but also to enlarge current knowledge of the consequences of reactor accidents. An international workshop on dose reconstruction was held in Bad Honnef, June 6 to 9, 1994, to address the problems which arise in dose reconstruction. The main objectives of this workshop were to bring together the best professional expertise and scientific knowledge and to achieve a better, multi-disciplinary harmonisation of the different scientific approaches. After intensive discussions the participants of this workshop formulated the following scientific recommendations for radiation dose reconstruction. (orig.)

  9. Implications of the accident at Chernobyl for safety regulation of commercial nuclear power plants in the United Sates: Volume 2, Appendix - Public comments and their disposition: Final report

    International Nuclear Information System (INIS)

    This report was prepared by the Nuclear Regulatory Commission (NRC) staff to assess the implications of the accident at the Chernobyl nuclear power plant as they relate to reactor safety regulation for commercial nuclear power plants in the United States. The facts used in this assessment have been drawn from the US fact-finding report(NUREG-1250) and its sources. The general conclusions of the document are that there are generic lessons to be learned but that no changes in regulations are needed due to the substantial differences in the design, safety features and operation of US plants as compared to those in the USSR. Given these general conclusions, further consideration of certain specific areas is recommended by the report. These include: administrative controls over reactor regulation, reactivity accidents, accidents at low or zero power, multi-unit protection, fires, containment, emergency planning, severe accident phenomena, and graphite-moderated reactors

  10. Implications of the accident at Chernobyl for safety regulation of commercial nuclear power plants in the United States: Volume 1, Main report: Final report

    International Nuclear Information System (INIS)

    This report was prepared by the Nuclear Regulatory Commission (NRC) staff to assess the implications of the accident at the Chernobyl nuclear power plant as they relate to reactor safety regulation for commercial nuclear power plants in the United States. The facts used in this assessment have been drawn from the US fact-finding report (NUREG-1250) and its sources. The general conclusions of the document are that there are generic lessons to be learned but that no changes in regulations are needed due to the substantial differences in the design, safety features and operation of US plants as compared to those in the USSR. Given these general conclusions, further consideration of certain specific areas is recommended by the report. These include: administrative controls over reactor regulation, reactivity accidents, accidents at low or zero power, multi-unit protection, fires, containment, emergency planning, severe accident phenomena, and graphite-moderated reactors

  11. Teaching About Nature's Nuclear Reactors

    CERN Document Server

    Herndon, J M

    2005-01-01

    Naturally occurring nuclear reactors existed in uranium deposits on Earth long before Enrico Fermi built the first man-made nuclear reactor beneath Staggs Field in 1942. In the story of their discovery, there are important lessons to be learned about scientific inquiry and scientific discovery. Now, there is evidence to suggest that the Earth's magnetic field and Jupiter's atmospheric turbulence are driven by planetary-scale nuclear reactors. The subject of planetocentric nuclear fission reactors can be a jumping off point for stimulating classroom discussions about the nature and implications of planetary energy sources and about the geomagnetic field. But more importantly, the subject can help to bring into focus the importance of discussing, debating, and challenging current thinking in a variety of areas.

  12. The legacy of Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Bojcun, M.

    1991-04-20

    This article looks at daily life in the Northern Ukraine, where the fallout effects from the Chernobyl nuclear reactor accident were felt most keenly. High levels of radioactive iodine 131, strontium 90 and caesium 137 are still present five years on and the health of the population, including those evacuated from the exclusion zones, is at risk from leukaemia and thyroid problems, especially among children. Other worrying reports suggest the occurence of a new disease, ''Chernobyl AIDs'', in which sufferers' immune systems are depressed. Other major outstanding problems include the integrity of the concrete sarcophagus enclosing the damaged reactor, and the continued consumption of locally grown contaminated food due to government inadequacies in supplying ''clean'' equivalents. (UK).

  13. After Chernobyl. Psychological factors affecting health after a nuclear disaster

    International Nuclear Information System (INIS)

    During his stay in Belarus, Ukraine and Russia the author learned much about the medical and psychological consequences of the Chernobyl accident, and about the rapidly changing societies of the former Soviet Union. The chapters of this dissertation may be regarded as being stations along the way in this learning process. Chapter 1 describes his first impressions and the accounts he heard about the events that followed the catastrophe. It summarizes the current knowledge about the radiological consequences of the disaster. Chapter 2 presents a review of the literature about the psychological impact of disasters, such as Chernobyl, Bhopal and Three Mile Island, events that are characterized by the release of potentially harmful quantities of toxic substances into the environment. Chapters 3 and 4 describe the painstaking process of obtaining the necessary reliable research instruments, which were totally lacking in the Russian language. Without such instruments no valid epidemiological research is possible. Furthermore, these research instruments were to provide a tool to assist the Byelorussian physicians in their daily practice, helping them to assess the presence of psychosocial and psychiatric problems in their patients in a more reliable fashion. Chapter 5 describes the mental health situation in the region and analyses the presence of high-risk groups towards whom special intervention programmes. Chapter 6 investigates the question to what extent the high levels of psychopathology in Gomel can be attributed to the impact of the Chernobyl disaster, even more than six years after the event. In chapter 7 the perspective is widened. The field of mental health is left behind and the domain of public health is addressed. This chapter describes the relationship between subjective health and illness behaviour in relation to objective clinical parameters of physical and mental health. Finally, in chapter 8, the findings from these studies are critically reviewed and

  14. Nuclear Reactor Engineering Analysis Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Carlos Chavez-Mercado; Jaime B. Morales-Sandoval; Benjamin E. Zayas-Perez

    1998-12-31

    The Nuclear Reactor Engineering Analysis Laboratory (NREAL) is a sophisticated computer system with state-of-the-art analytical tools and technology for analysis of light water reactors. Multiple application software tools can be activated to carry out different analyses and studies such as nuclear fuel reload evaluation, safety operation margin measurement, transient and severe accident analysis, nuclear reactor instability, operator training, normal and emergency procedures optimization, and human factors engineering studies. An advanced graphic interface, driven through touch-sensitive screens, provides the means to interact with specialized software and nuclear codes. The interface allows the visualization and control of all observable variables in a nuclear power plant (NPP), as well as a selected set of nonobservable or not directly controllable variables from conventional control panels.

  15. Nuclear reactors and fuel cycle

    International Nuclear Information System (INIS)

    The Center for Nuclear Engineering has shown expertise in the field of nuclear and energy systems ad correlated areas. Due to the experience obtained over decades in research and technological development at Brazilian Nuclear Program personnel has been trained and started to actively participate in the design of the main system that will compose the Brazilian Multipurpose Reactor (RMB) which will make Brazil self-sufficient in the production of radiopharmaceuticals. The institution has participated in the monitoring and technical support concerning the safety, licensing and modernization of the research reactors IPEN/MB-01 and IEA-R1. The Nuclear Fuel Center is responsible for the production of the nuclear fuel necessary for the continuous operation of the IEA-R1 research reactor. Development of new fuel technologies is also a permanent concern

  16. Radiological consequences of the Chernobyl reactor accident; Radiologische Folgen des Tschernobyl-Ungluecks

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, P.

    1996-05-01

    Large areas of Belarus, Russia, and the Ukraine have been highly contaminated by the radioactive fallout from the reactor accident at Chernobyl. The most affected areas are around Chernobyl and east of Gomel in Belarus, where part of the radioactive fallout came down with rain. The article maps the radioactive contamination through cesium 137 and iodine 131, and summarizes the immediate action taken at the time, as well as long-term remedial action for decontamination of soils. Data are given on the radiation exposure of the population, in particular doses to the thyroid, and prognoses on the incidence of thyroid cancer. (VHE) [Deutsch] Durch den Reaktorunfall von Tschernobyl wurden groessere Flaechen von Belarus, Russland und der Ukraine stark radioaktiv kontaminiert. Besonders betroffen sind die Umgebung von Tschernobyl sowie die Gegend oestlich von Gomel (Belarus), wo die radioaktive Wolke teilweise ausregnete. Der Artikel beschreibt die Belastung mit Caesium 137 und Iod 131 sowie die ergriffenen Sofortmassnahmen und die langfristigen Massnahmen zur Dekontamination der betroffenen Boeden. Die Strahlenbelastung der Bevoelkerung, v.a. die Schilddruesendosen, werden beschrieben, fuer Schilddruesenkrebs werden Prognosen gegeben. (VHE)

  17. Liability problems arising from nuclear reactor accidents

    International Nuclear Information System (INIS)

    In case of damage to health or property, it has always been approved legal tradition in all highly developed legal systems to perform compensation for damage in money. This principle also applies to damage caused by nuclear accidents. In the F.R.G., care has been taken at a very early stage to provide for appropriate liability provisions to afford financial security to the extent required by the special hazards involved in the peaceful use of atomic energy. Recent events have shown that the legal provisions available are appropriate and practicable. Citizens affected will receive fair compensation for damage. The Federal Administrative Office so far counted 30.392 applications for compensation in compliance with section 38, sub-sec. (2) Atomic Energy Act. Up to June 16, 1986, payments for compensation of losses amounted to DM 38.7 millions. By accepting the claims for compensation the State provides protection for German nationals and persons of equal rank. A limitation to DM one billion for compensation for damage caused by nuclear energy seems to be appropriate also in the light of the Chernobyl reactor accident. (orig./HP)

  18. Random processes in nuclear reactors

    CERN Document Server

    Williams, M M R

    1974-01-01

    Random Processes in Nuclear Reactors describes the problems that a nuclear engineer may meet which involve random fluctuations and sets out in detail how they may be interpreted in terms of various models of the reactor system. Chapters set out to discuss topics on the origins of random processes and sources; the general technique to zero-power problems and bring out the basic effect of fission, and fluctuations in the lifetime of neutrons, on the measured response; the interpretation of power reactor noise; and associated problems connected with mechanical, hydraulic and thermal noise sources

  19. The accident of Chernobyl

    International Nuclear Information System (INIS)

    RBMK reactors (reactor control, protection systems, containment) and the nuclear power plant of Chernobyl are first presented. The scenario of the accident is given with a detailed chronology. The actions and consequences on the site are reviewed. This report then give the results of the source term estimation (fision product release, core inventory, trajectories, meteorological data...), the radioactivity measurements obtained in France. Health consequences for the French population are evoked. The medical consequences for the population who have received a high level of doses are reviewed

  20. Technique of nuclear reactors controls

    International Nuclear Information System (INIS)

    This report deal about 'Techniques of control of the nuclear reactors' in the goal to achieve the control of natural uranium reactors and especially the one of Saclay. This work is mainly about the measurement into nuclear parameters and go further in the measurement of thermodynamic variables,etc... putting in relief the new features required on behalf of the detectors because of their use in the thermal neutrons flux. In the domain of nuclear measurement, we indicate the realizations and the results obtained with thermal neutron detectors and for the measurement of ionizations currents. We also treat the technical problem of the start-up of a reactor and of the reactivity measurement. We give the necessary details for the comprehension of all essential diagrams and plans put on, in particular, for the reactor of Saclay. (author)

  1. 131I content in canine thyroids in the Warsaw urban area after the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    The levels of 131I were determined in the thyroids of 20 dogs from Warsaw submitted to euthanasia between May and September 1986. The animals were living with humans and were in similar way exposed to contamination after the Chernobyl reactor accident. After calculation of the radioactivity for May 10th the contamination was found to range from 142.9 to 1372.9 Bq. These values corresponded to the contamination of human thyroids as reported by Central Laboratory for Radiation Protection in Warsaw. From the begining of May to the end of November the number of operations performed in dogs for pathological thyroid hyperplasia was six times higher than in the preceding time period. 5 refs., 2 tabs. (author)

  2. Nuclear reactors and fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-07-01

    The Nuclear Fuel Center (CCN) of IPEN produces nuclear fuel for the continuous operation of the IEA-R1 research reactor of IPEN. The serial production started in 1988, when the first nuclear fuel element was delivered for IEA-R1. In 2011, CCN proudly presents the 100{sup th} nuclear fuel element produced. Besides routine production, development of new technologies is also a permanent concern at CCN. In 2005, U{sub 3}O{sub 8} were replaced by U{sub 3}Si{sub 2}-based fuels, and the research of U Mo is currently under investigation. Additionally, the Brazilian Multipurpose Research Reactor (RMB), whose project will rely on the CCN for supplying fuel and uranium targets. Evolving from an annual production from 10 to 70 nuclear fuel elements, plus a thousand uranium targets, is a huge and challenging task. To accomplish it, a new and modern Nuclear Fuel Factory is being concluded, and it will provide not only structure for scaling up, but also a safer and greener production. The Nuclear Engineering Center has shown, along several years, expertise in the field of nuclear, energy systems and correlated areas. Due to the experience obtained during decades in research and technological development at Brazilian Nuclear Program, personnel has been trained and started to actively participate in design of the main system that will compose the Brazilian Multipurpose Reactor (RMB) which will make Brazil self-sufficient in production of radiopharmaceuticals. The institution has participated in the monitoring and technical support concerning the safety, licensing and modernization of the research reactors IPEN/MB-01 and IEA-R1. Along the last two decades, numerous specialized services of engineering for the Brazilian nuclear power plants Angra 1 and Angra 2 have been carried out. The contribution in service, research, training, and teaching in addition to the development of many related technologies applied to nuclear engineering and correlated areas enable the institution to

  3. Nuclear reactors and fuel cycle

    International Nuclear Information System (INIS)

    The Nuclear Fuel Center (CCN) of IPEN produces nuclear fuel for the continuous operation of the IEA-R1 research reactor of IPEN. The serial production started in 1988, when the first nuclear fuel element was delivered for IEA-R1. In 2011, CCN proudly presents the 100th nuclear fuel element produced. Besides routine production, development of new technologies is also a permanent concern at CCN. In 2005, U3O8 were replaced by U3Si2-based fuels, and the research of U Mo is currently under investigation. Additionally, the Brazilian Multipurpose Research Reactor (RMB), whose project will rely on the CCN for supplying fuel and uranium targets. Evolving from an annual production from 10 to 70 nuclear fuel elements, plus a thousand uranium targets, is a huge and challenging task. To accomplish it, a new and modern Nuclear Fuel Factory is being concluded, and it will provide not only structure for scaling up, but also a safer and greener production. The Nuclear Engineering Center has shown, along several years, expertise in the field of nuclear, energy systems and correlated areas. Due to the experience obtained during decades in research and technological development at Brazilian Nuclear Program, personnel has been trained and started to actively participate in design of the main system that will compose the Brazilian Multipurpose Reactor (RMB) which will make Brazil self-sufficient in production of radiopharmaceuticals. The institution has participated in the monitoring and technical support concerning the safety, licensing and modernization of the research reactors IPEN/MB-01 and IEA-R1. Along the last two decades, numerous specialized services of engineering for the Brazilian nuclear power plants Angra 1 and Angra 2 have been carried out. The contribution in service, research, training, and teaching in addition to the development of many related technologies applied to nuclear engineering and correlated areas enable the institution to fulfill its mission that is to

  4. Fundamentals of Nuclear Reactor Physics

    CERN Document Server

    Lewis, E E

    2008-01-01

    This new streamlined text offers a one-semester treatment of the essentials of how the fission nuclear reactor works, the various approaches to the design of reactors, and their safe and efficient operation. The book includes numerous worked-out examples and end-of-chapter questions to help reinforce the knowledge presented. This textbook offers an engineering-oriented introduction to nuclear physics, with a particular focus on how those physics are put to work in the service of generating nuclear-based power, particularly the importance of neutron reactions and neutron behavior. Engin

  5. Surface activity distribution measurements and establishment of a dose rate map inside the destroyed Chernobyl reactor

    International Nuclear Information System (INIS)

    A Gamma Locator designed for contamination survey inside the reactor hall of the 4th unit of Chernobyl NNP has been developed. The device consists of a detector head and a remote control computer connected by a 150 m long cable. The detector head (dimensions: 500 mm by 500 mm by 400 mm; weight: about 40 kg) is a collimated scintillation gamma detector (the collimation angle is 10 deg.). It is installed on a scanning unit and was placed inside the reactor hall. The Gamma Locator scans all surfaces of the reactor hall with angular steps (≤ 1 deg. vertically as well as horizontally) and the particle fluence from the corresponding direction is recorded. The distance between the device head and the measured surface is instantaneously registered by a laser distance gauge. Inside the collimator there is a small CCD camera which makes it possible to obtain a visible image of the measured surface. The effective surface activity levels are presented in colour on the screen of the control computer. The gamma detector essentially consists of a CsI(TI) scintillator crystal (φ 8 mm in diameter, 2.5 mm in thickness) and a Si photodiode. The detector energy resolution is about 8% for radiation from 137Cs. The exposure dose rate distribution in the reactor hall is estimated from the measured effective surface activities /137Cs is the main gamma emitting isotope inside the reactor hall). The results of dose rate calculations are presented in colour superposed on a drawing of the reactor hall. (au)

  6. Surface activity distribution measurements and establishment of a dose rate map inside the destroyed Chernobyl reactor

    Energy Technology Data Exchange (ETDEWEB)

    Chesnokov, A.V.; Fedin, V.I.; Gulyaev, A.A. [RECOM Ltd., Moscow (Russian Federation)] [and others

    1999-02-01

    A Gamma Locator designed for contamination survey inside the reactor hall of the 4th unit of Chernobyl NNP has been developed. The device consists of a detector head and a remote control computer connected by a 150 m long cable. The detector head (dimensions: 500 mm by 500 mm by 400 mm; weight: about 40 kg) is a collimated scintillation gamma detector (the collimation angle is 10 deg.). It is installed on a scanning unit and was placed inside the reactor hall. The Gamma Locator scans all surfaces of the reactor hall with angular steps ({<=} 1 deg. vertically as well as horizontally) and the particle fluence from the corresponding direction is recorded. The distance between the device head and the measured surface is instantaneously registered by a laser distance gauge. Inside the collimator there is a small CCD camera which makes it possible to obtain a visible image of the measured surface. The effective surface activity levels are presented in colour on the screen of the control computer. The gamma detector essentially consists of a CsI(TI) scintillator crystal ({phi} 8 mm in diameter, 2.5 mm in thickness) and a Si photodiode. The detector energy resolution is about 8% for radiation from {sup 137}Cs. The exposure dose rate distribution in the reactor hall is estimated from the measured effective surface activities ({sup 137}Cs is the main gamma emitting isotope inside the reactor hall). The results of dose rate calculations are presented in colour superposed on a drawing of the reactor hall. (au) 1 tab., 28 ills., 16 refs.

  7. nuclear reactor design calculations

    International Nuclear Information System (INIS)

    In this work , the sensitivity of different reactor calculation methods, and the effect of different assumptions and/or approximation are evaluated . A new concept named error map is developed to determine the relative importance of different factors affecting the accuracy of calculations. To achieve this goal a generalized, multigroup, multi dimension code UAR-DEPLETION is developed to calculate the spatial distribution of neutron flux, effective multiplication factor and the spatial composition of a reactor core for a period of time and for specified reactor operating conditions. The code also investigates the fuel management strategies and policies for the entire fuel cycle to meet the constraints of material and operating limitations

  8. The results of the research and studies concerning the information about the Chernobyl nuclear disaster

    International Nuclear Information System (INIS)

    The studies conducted by the National Board of Psychological Defence after the Chernobyl nuclear accident concern questions of great importance about crisis information. The Chernobyl fallout created problems for the mass media and the authorities. Both lacked individual preparedness. The knowledge necessary to face strong demands for information from the public was lacking. A sign of this lack of knowledge and experience was shown when individual journalists - contrary to their usual behaviour - uncritically accepted the sometimes ambiguous information coming from the central authorities. For the authorities it was very much the same. The expert authority, the National Institute for Radiation Protection, had quite a lot of know-how, but no resources for such extensive information as the situation required. Significant problems must be solved concerning the cooperation between central and regional authorities. Direct contacts must be established so that both types of authorities do not learn through mass media what has been decided. The wordings of the messages conveyed in such critical situations must be a matter of more concern. Facts known by the authorities must be presented in a way comprehensible to the public. Technical terms and units must be used with great care. Negative information must of course be presented but measures should be taken to countermand the negative effect. A special responsibility should rest with the school system. The difficulties of informing the public after the Chernobyl disaster were still more emphasized by the study of how the brochure After Chernobyl was received

  9. Chernobyl after five years and over

    International Nuclear Information System (INIS)

    On April 26th 1986 the catastrophe occurred at the nuclear electric power generation system. The first inkling of the accident was known through the Swedish monitoring station about the radioactive fallout. It was also in 1986 that the USSR gave an idea of an earlier accident which happened in 1957. The Chernobyl reactor has pressure tubes and is a pressure vessel reactor. Graphite is used as an industrial material. In western reactors in USA with the increase in heat, power generation comes down. The international AEC discussed the Chernobyl comprehensively and came out with conclusion of deficiency in design which was accepted by the Soviet side without any demur. In 1970, in UK an accident has been reported with pressurized reactor. In 1987, Chernobyl was discussed under the chair of Eugene Volkov by USSR. In 1989, another conference was arranged at Sicily. The first annual nuclear safety met at Minsk in 1990 (June); USSR/USA meet on Chernobyl was also held at Solchin in 1989. A future meeting on Chernobyl was held at Paris in July 1991. In all these meetings, it is emphasized that more training and safety culture establishment was necessary by the international nuclear safety advisory group on safety. (author). 2 refs., 1 tab

  10. GE's advanced nuclear reactor designs

    International Nuclear Information System (INIS)

    The excess of US electrical generating capacity which has existed for the past 15 years is coming to an end as we enter the 1990s. Environmental and energy security issues associated with fossil fuels are kindling renewed interest in the nuclear option. The importance of these issues are underscored by the National Energy Strategy (NES) which calls for actions which open-quotes are designed to ensure that the nuclear power option is available to utilities.close quotes Utilities, utility associations, and nuclear suppliers, under the leadership of the Nuclear Power Oversight Committee (NPOC), have jointly developed a 14-point strategic plan aimed at establishing a predictable regulatory environment, standardized and pre-licensed Advanced Light Water Reactor (ALWR) nuclear plants, resolving the long-term waste management issue, and other open-quotes enabling conditions.close quotes GE is participating in this national effort and GE's family of advanced nuclear power plants feature two reactor designs, developed on a common technology base, aimed at providing a new generation of nuclear plants to provide safe, clean, economical electricity to the world's utilities in the 1990s and beyond. Together, the large-size (1300 MWe) Advanced Boiling Water Reactor (ABWR) and the small-size (600 MWe) Simplified Boiling Water Reactor (SBWR) are innovative, near-term candidates for expanding electrical generating capacity in the US and worldwide. Both possess the features necessary to do so safety, reliably, and economically

  11. Radiation safety during construction of the encapsulation at the Chernobyl nuclear power plant

    International Nuclear Information System (INIS)

    A review is given of the main radiation safety problems which were solved during design and construction of the encapsulation for Unit 4 of the Chernobyl nuclear power plant which was destroyed in the accident of 26 April 1986. Information is given on the conditions under which large scale restoration work was performed, and on the design stipulations laid down for construction of the encapsulation for the destroyed unit. The paper discusses the technical, organizational and health measures which were used to ensure that radiation safety regulations and standards were observed during construction. The problems of organizing a radiation safety service inside the construction and assembly organization which built the encapsulation are discussed. Finally, conclusions are drawn with regard to the experience which has been gained in the area of radiation safety implementation during large scale post-accident restoration work under problematic radiation conditions such as those at the Chernobyl nuclear power plant site. (author). 7 refs, 6 figs, 1 tab

  12. Chernobyl: exclusive investigation. How the French nuclear lobby buries the truth in contaminated areas. The After-Chernobyl or 'Living happy' in contaminated area

    International Nuclear Information System (INIS)

    According to the results of this inquiry, the CEPN (study centre on assessment of protection in the nuclear sector) has been created by the main actors of the nuclear industrial sector (EFG, Cogema, CEA and IRSN) and is at the origin of the ETHOS and CORE projects. Moreover, these projects have been financed by public funds. It also shows that the FNSEA (farmer trade union) has been allied to the French nuclear lobby for the distribution probably contaminated and radioactive foodstuff. It evokes the case of Belarus researcher who denounced such contamination and the misappropriation of international funds, and who was sent to jail. It comments the collaboration between the French nuclear sector and the Belarus regime, denounces how the truth about Chernobyl has been hidden, the cynical results of the ETOS program which would imply the consumption of contaminated foodstuff in France in case of nuclear accident. Some proposals are made: to dismantle the CEPN, to stop the participation of French organisations to the CORE and FARMING programs, creation of an independent commission on the consequences of the Chernobyl accident, and so on. For the authors, phasing out nuclear is the only solution o avoid a new Chernobyl

  13. BWR type nuclear reactor

    International Nuclear Information System (INIS)

    Purpose: To simplify the structure of an emergency core cooling system while suppressing the flow out of coolants upon rapture accidents in a coolant recycling device of BWR type reactors. Constitution: Recirculation pumps are located at a position higher than the reactor core in a pressure vessel, and the lower plenum is bisected vertically by a partition plate. Further, a gas-liquid separator is surrounded with a wall and the water level at the outer side of the wall is made higher than the water level in the inside of the wall. In this structure, coolants are introduced from the upper chamber in the lower plenum into the reactor core, and the steams generated in the reactor core are separated in the gas-liquid separator, whereby the separated liquid is introduced as coolants by way of the inner chamber into the lower chamber of the lower plenum and further sent by way of the outer chamber into the reactor core. Consequently, idle rotation of the recycling pumps due to the flow-in of saturated water is prevented and loss of coolants in the reactor core can also be prevented upon raptures in the pipeway and the driving section of the pump connected to the pressure vessel and in the bottom of the pressure vessel. (Horiuchi, T.)

  14. Radiation management and health management at the Chernobyl nuclear power plant

    International Nuclear Information System (INIS)

    This paper describes the measures taken by the Chernobyl nuclear power plant since the accident in April 1986 to date, compares them with the situation of the current Fukushima nuclear accident, and introduces the contents of the authors' visit and coverage in October 2013, including the report of radiation damage. At the Chernobyl site, a new sarcophagus is under construction since 2012. The health care of the workers working at the new and old sarcophaguses of the Chernobyl nuclear power plant is carried out at a national level of Ukraine, which is an important management for decommissioning work. Health diagnosis is also applied to the workers in the new sarcophagus, and radiation-related disease is not reported at present. The number of the persons who died from acute radiation exposure diseases after the accident was 28. It was reported that chronic lymphocytic leukemia (CLL) appeared significantly when the radiation exceeded 100 mSv. The workers who wish to work at the Chernobyl nuclear power plant must pass the test and obtain national qualifications, and then they are able to work for the first time. In the check-in medical control, about half of applicants were rejected. Workers who work at the new sarcophagus are subject to comprehensive health management under the Ukrainian law. There were 58 people who reached annual exposure dose limit of 20 mSv or more among 7,529 people, the cause of which may be the work at the areas of high radiation dose. Even in Fukushima, it is important to perform high quality management based on centralized medical examination, and to further analyze the effects of low-dose exposure to radiation. (A.O.)

  15. Lessons learned from the TMI-2 accident and Chernobyl nuclear disaster for nuclear safety innovation

    International Nuclear Information System (INIS)

    The 2011 off the Pacific coast of Tohoku Pacific Earthquake and the Tsunami gave the serious damage to the Fukushima-Daiichi Nuclear Power Plants (NPPs). The accidents occurred in Unit 1, 2, 3 and 4. It is said that the height of tsunami attacked Fukushima NPP was more than 14m. After 50 minutes from the automatic shut-down, tsunami attacked the NPPs in Fukushima Daiichi NPPs. For example, the Unit 1 lost A/C power caused the loss of water injection function; it made the core meltdown and unusual increase of PCV pressure in the midnight to March 11th to 12th morning. Though the Unit one has the Isolation Condenser Core Cooling system, it was stopped by the operator to keep the cooling rate of 55degC/h. Finally, the isolation signal was transmitted from the control room to the motor driven isolation valves when the control room's battery discharged. It was the initiation of the core meltdown. The lessons from the TMI-2 accident, human error and instrumentation and control system trouble cased the core damage. Though the NPPs in European counties have filtered venting system after the Chernobyl Nuclear disaster, there are not filtered venting system connected the containment vessel in Japanese NPPs. If the Fukushima Daiichi NPPs have filtered venting system, the venting could be much earlier and no nuclear disaster would be occurred. (author)

  16. Innovative designs of nuclear reactors

    International Nuclear Information System (INIS)

    The world development scenarios predict at least a 2.5 time increase in the global consumption of primary energy in the first half of the twenty-first century. Much of this growth can be provided by the nuclear power which possesses important advantages over other energy technologies. However, the large deployment of nuclear sources may take place only when the new generation of reactors appears on the market and will be free of the shortcomings found in the existing nuclear power installations. The public will be more inclined to accept nuclear plants that have better economics; higher safety; more efficient management of the radioactive waste; lower risk of nuclear weapons proliferation, and provided that the focus is made on the energy option free of ∇e2 generation. Currently, the future of nuclear power is trusted to the technology based on fast reactors and closed fuel cycle. The latter implies reprocessing of the spent nuclear fuel of the nuclear plants and re-use of plutonium produced in power reactors

  17. AREVA's nuclear reactors portfolio

    International Nuclear Information System (INIS)

    A reasonable assumption for the estimated new build market for the next 25 years is over 340 GWe net. The number of prospect countries is growing almost each day. To address this new build market, AREVA is developing a comprehensive portfolio of reactors intended to meet a wide range of power requirements and of technology choices. The EPR reactor is the flagship of the fleet. Intended for large power requirements, the four first EPRs are being built in Finland, France and China. Other countries and customers are in view, citing just two examples: the Usa where the U.S. EPR has been selected as the technology of choice by several U.S utilities; and the United Kingdom where the Generic Design Acceptance process of the EPR design submitted by AREVA and EDF is well under way, and where there is a strong will to have a plant on line in 2017. For medium power ranges, the AREVA portfolio includes a boiling water reactor and a pressurized water reactor which both offer all of the advantages of an advanced plant design, with excellent safety performance and competitive power generation cost: -) KERENA (1250+ MWe), developed in collaboration with several European utilities, and in particular with Eon; -) ATMEA 1 (1100+ MWe), a 3-loop evolutionary PWR which is being developed by AREVA and Mitsubishi. AREVA is also preparing the future and is deeply involved into Gen IV concepts. It has developed the ANTARES modular HTR reactor (pre-conceptual design completed) and is building upon its vast Sodium Fast Reactor experience to take part into the development of the next prototype. (author)

  18. Nuclear reactor PBMR and cogeneration; Reactor nuclear PBMR y cogeneracion

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-10-15

    In recent years the nuclear reactor designs for the electricity generation have increased their costs, so that at the moment costs are managed of around the 5000 US D for installed kw, reason for which a big nuclear plant requires of investments of the order of billions of dollars, the designed reactors as modular of low power seek to lighten the initial investment of a big reactor dividing the power in parts and dividing in modules the components to lower the production costs, this way it can begin to build a module and finished this to build other, differing the long term investment, getting less risk therefore in the investment. On the other hand the reactors of low power can be very useful in regions where is difficult to have access to the electric net being able to take advantage of the thermal energy of the reactor to feed other processes like the water desalination or the vapor generation for the processes industry like the petrochemical, or even more the possible hydrogen production to be used as fuel. In this work the possibility to generate vapor of high quality for the petrochemical industry is described using a spheres bed reactor of high temperature. (Author)

  19. Study of a cohort of Latvian workers having participated to the decontamination of the nuclear site of Chernobyl

    International Nuclear Information System (INIS)

    In the consequences attributable to the accident at the Chernobyl nuclear power plant, it is debated whether post-disaster psycho-pathology is related to the perception of the level of contamination or the level of contamination itself. To address this issue, the authors have assessed the association of various exposure mental and psychosomatic distress, on a sample of 1,1412 Latvian liquidators drawn from the State Latvian Chernobyl clean-up workers registry. The outcome considered was a mixed mental/psychosomatic disorder occurring during the time period 1986-1995. Comparisons between subgroups of the cohort, classified according to exposure type or level, were based on the proportional hazards model. Length of work (≥ 28 days) in a 10 km radius from the reactor (relative risk (RR) = 1.39, 95 percent confidence interval (CI) 1.14-1.70), work (> 1 time) on the damaged reactor roof (RR 1.46, 95 percent CI 1.02-2.09), forest work (RR 1.41,95 percent CI 1.19-1.68), and fresh fruits consumption (≥ 1 time/day) (RR 1.72,95 percent CI 1.12-2.65) are risk factors for mixed mental/ psychosomatic disorder. Construction of the sarcophagus (RR 1.82, 95 percent CI 0.89-3.72), is also associated with this outcome, although non significantly. These findings confirm that some exposure variables represent risk factors for mental disorders and suggest some radiation-induced consequences although surely overweight by stress-related effects. (author)

  20. Micro-analytical uranium isotope and chemical investigations of zircon crystals from the Chernobyl “lava” and their nuclear fuel inclusions

    Energy Technology Data Exchange (ETDEWEB)

    Pöml, P., E-mail: Philipp.POEML@ec.europa.eu [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Burakov, B. [Laboratory of Applied Mineralogy and Radiogeochemistry, V.G. Khlopin Radium Institute, 28, 2-nd Murinskiy Ave., St. Petersburg 194021 (Russian Federation); Geisler, T. [Steinmann Institut für Geologie, Mineralogie und Paläontologie, University of Bonn, Poppelsdorfer Schloss, 53115 Bonn (Germany); Walker, C.T. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Grange, M.L.; Nemchin, A.A. [Department of Applied Geology, Western Australian School of Mines, Curtin University, GPO Box U1987, Western Australia 6845 (Australia); Berndt, J. [Institut für Mineralogie, Westfälische Wilhelms-Universität, Corrensstraße 24, 48149 Münster (Germany); Fonseca, R.O.C. [Steinmann Institut für Geologie, Mineralogie und Paläontologie, University of Bonn, Poppelsdorfer Schloss, 53115 Bonn (Germany); Bottomley, P.D.W.; Hasnaoui, R. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany)

    2013-08-15

    U isotope data measured on real fragments of the Chernobyl nuclear fuel included in zircon crystals crystallised from the Chernobyl “lava” are presented for the first time. The U isotope data show no anomalies and lie within the expected burnup values for the Chernobyl nuclear fuel. However, the U concentration, the U isotopic composition, and the Ti concentration in the host zircon vary significantly within single crystals as well as between single crystals. Our results indicate that during the time of melt activity temperature and melt composition likely varied considerably. New melt was formed progressively (and solidified) during the accident that reacted and mixed with pre-existing melt that never fully equilibrated. In such an environment zircon crystals crystallised at temperatures below 1250 °C, as estimated from thermodynamic considerations along with the observation that the centre of the investigated zircon crystal contains monoclinic ZrO{sub 2} inclusions. Since the zircon crystals crystallised before the silicate melt spread out into the reactor block basement, the flow of the melt into the basement must also have occurred at temperatures below 1250 °C.

  1. Nuclear reactors and disarmament

    International Nuclear Information System (INIS)

    From a brief analysis of the perspectives of nuclear weapons arsenals reduction, a rational use of the energetic potential of the ogives and the authentic destruction of its warlike power is proposed. The fissionable material conversion contained in the nuclear fuel ogives for peaceful uses should be part of the disarmament agreements. This paper pretends to give an approximate idea on the resources re assignation implicancies. (Author)

  2. Nuclear reactor container

    International Nuclear Information System (INIS)

    Upon reactor accident, hydrogen and oxygen are generated by water-zirconium reaction and radiolysis of water, which are accumulated in the reactor. If the concentration of hydrogen and oxygen exceeds a burning limit, there is a possibility of hydrogen burning to cause a danger of deteriorating the integrity of the reactor container and the equipments therein. The limit for the occurrence of the detonation is determined by a relationship between the scale of a detonation cell and the size of the container, and if the scale is greater than the container, the detonation does not occur. The scale of the cell is determined by a gas combustion rate and, if the combustion reaction is suppressed, detonation does not occur even in a large container. Then, an appropriate diluent is added to increase heat capacity of a gas mixture to thereby suppress the temperature elevation of the gas. Incombustible gases having a great heat capacity are preferred for the diluent, and CO2 is used. As the concentration of the CO2 gas to be added is increased, the detonation cell is made greater. Thus, occurrence of detonation due to combustion of the accumulated hydrogen can be prevented. (N.H.)

  3. Health requirements for nuclear reactor operators

    International Nuclear Information System (INIS)

    The health prerequisites established for the qualification of nuclear reactor operators according to CNEN-NE-1.01 Guidelines Licensing of nuclear reactor operators, CNEN-12/79 Resolution, are described. (M.A.)

  4. Nuclear Reactors and Technology; (USA)

    Energy Technology Data Exchange (ETDEWEB)

    Cason, D.L.; Hicks, S.C. (eds.)

    1991-01-01

    Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database (EDB) during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency's Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on EDB and Nuclear Science Abstracts (NSA) database. Current information, added daily to EDB, is available to DOE and its contractors through the DOE integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user's needs.

  5. Instrumentation for nuclear reactor control

    International Nuclear Information System (INIS)

    This lecture is concerned with engineers and technicians not specialized in nuclear reactor control. The different methods of measurement used are briefly reviewed: current or pulse measurement, and Campbell system; the electronic networks are described and a part is devoted to the cables connecting detectors and electronic assemblies

  6. Behaviour of Chernobyl fallout radionuclides deposited on peat and urban surfaces in Finland

    International Nuclear Information System (INIS)

    In the thesis the impact of the Chernobyl nuclear reactor accident on Finland was studied in three aspects: (1) the areal distribution of Chernobyl fallout in Finland was determined by measuring peat samples, (2) the behaviour of fallout radionuclides was investigated in the combustion of peat in power plants, and (3) the removal rates of fallout radionuclides on urban surfaces were resolved

  7. Nuclear reactor effluent monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Minns, J.L.; Essig, T.H. [Nuclear Regulatory Commission, Washington, DC (United States)

    1993-12-31

    Radiological environmental monitoring and effluent monitoring at nuclear power plants is important both for normal operations, as well as in the event of an accident. During normal operations, environmental monitoring verifies the effectiveness of in-plant measures for controlling the release of radioactive materials in the plant. Following an accident, it would be an additional mechanism for estimating doses to members of the general public. This paper identifies the U.S. Nuclear Regulatory Commission (NRC) regulatory basis for requiring radiological environmental and effluent monitoring, licensee conditions for effluent and environmental monitoring, NRC independent oversight activities, and NRC`s program results.

  8. Medical preparedness: Chernobyl as a model for southeastern Michigan

    International Nuclear Information System (INIS)

    The Detroit Chapter of Physicians for Social Responsibility developed a project to evaluate the potential response of the local medical community to a small nuclear disaster involving radiation injuries. The model was patterned after the Chernobyl nuclear power plant disaster of April 26, 1986. They surveyed the potential response to a hypothetical disaster at the Enrico Fermi II nuclear reactor located south of Detroit

  9. Utilization of nuclear research reactors

    International Nuclear Information System (INIS)

    Full text: Report on an IAEA interregional training course, Budapest, Hungary, 5-30 November 1979. The course was attended by 19 participants from 16 Member States. Among the 28 training courses which the International Atomic Energy Agency organized within its 1979 programme of technical assistance was the Interregional Training Course on the Utilization of Nuclear Research Reactors. This course was held at the Nuclear Training Reactor (a low-power pool-type reactor) of the Technical University, Budapest, Hungary, from 5 to 30 November 1979 and it was complemented by a one-week Study Tour to the Nuclear Research Centre in Rossendorf near Dresden, German Democratic Republic. The training course was very successful, with 19 participants attending from 16 Member States - Bangladesh, Bolivia, Czechoslovakia, Ecuador, Egypt, India, Iraq, Korean Democratic People's Republic, Morocco, Peru, Philippines, Spain, Thailand, Turkey, Vietnam and Yugoslavia. Selected invited lecturers were recruited from the USA and Finland, as well as local scientists from Hungarian institutions. During the past two decades or so, many research reactors have been put into operation around the world, and the demand for well qualified personnel to run and fully utilize these facilities has increased accordingly. Several developing countries have already acquired small- and medium-size research reactors mainly for isotope production, research in various fields, and training, while others are presently at different stages of planning and installation. Through different sources of information, such as requests to the IAEA for fellowship awards and experts, it became apparent that many research reactors and their associated facilities are not being utilized to their full potential in many of the developing countries. One reason for this is the lack of a sufficient number of trained professionals who are well acquainted with all the capabilities that a research reactor can offer, both in research and

  10. Economic analysis of nuclear reactors

    International Nuclear Information System (INIS)

    The report presents several methods for estimating the power costs of nuclear reactors. When based on a consistent set of economic assumptions, total power costs may be useful in comparing reactor alternatives. The principal items contributing to the total power costs of a nuclear power plant are: (1) capital costs, (2) fuel cycle costs, (3) operation and maintenance costs, and (4) income taxes and fixed charges. There is a large variation in capital costs and fuel expenses among different reactor types. For example, the standard once-through LWR has relatively low capital costs; however, the fuel costs may be very high if U3O8 is expensive. In contrast, the FBR has relatively high capital costs but low fuel expenses. Thus, the distribution of expenses varies significantly between these two reactors. In order to compare power costs, expenses and revenues associated with each reactor may be spread over the lifetime of the plant. A single annual cost, often called a levelized cost, may be obtained by the methods described. Levelized power costs may then be used as a basis for economic comparisons. The paper discusses each of the power cost components. An exact expression for total levelized power costs is derived. Approximate techniques of estimating power costs will be presented

  11. Nuclear reactor fuelling machine

    International Nuclear Information System (INIS)

    The refuelling machine described comprises a rotatable support structure having a guide tube attached to it by a parellel linkage mechanism, whereby the guide tube can be displaced sideways from the support structure. A gripper unit is housed within the guide tube for gripping the end of a fuel assembly or other reactor component and has means for maintenance in the engaging condition during travel of the unit along the guide tube, except for a small portion of the travel at one end of the guide tube, where the inner surface of the guide tube is shaped so as to maintain the gripper unit in a disengaging condition. The gripper unit has a rotatable head, means for moving it linearly within the guide tube so that a component carried by the unit can be housed in the guide tube, and means for rotating the head of the unit through 1800 relative to its body, to effect rotation of a component carried by the unit. The means for rotating the head of the gripper unit comprises ring and pinion gearing, operable through a series of rotatable shafts interconnected by universal couplings. The reason for provision for 1800 rotation is that due to the variation in the neutron flux across the reactor core the side of a fuel assembly towards the outside of the core will be subjected to a lower neutron flux and therefore will grow less than the side of the fuel assembly towards the inside of the core. This can lead to bowing and possible jamming of the fuel assemblies. Full constructional details are given. See also BP 1112384. (U.K.)

  12. Liquid-cooled nuclear reactor

    International Nuclear Information System (INIS)

    Hydrogen can be added to nuclear reactors with a liquid hydrogen-containing coolant on the suction side of a high pressure pump in the purification system. According to the invention this is performed by means of a liquid jet condenser which uses the coolant as liquid and which is preferably charged from the pressure side of the high pressure pump and conveys the liquid to a mixer connected in series with the high pressure pump. The invention is to be used especially in pressurized water reactors. (orig.)

  13. Total nuclear phaseout. 30 years after Chernobyl. What still has to be done; Alle aussteigen. 30 Jahre nach Tschernobyl. Was noch zu tun ist

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-03-15

    The brochure of the German Federal Environment Ministry on the necessity of total nuclear phaseout 30 years after Chernobyl discusses the following issues that still have to be done: Search for a final repository in deep rocks, building of a steel dome for Chernobyl and the roadmap for nuclear phaseout.

  14. Radioactive contamination of Bavarian game as a result of the Chernobyl reactor accident. Pt. 1

    International Nuclear Information System (INIS)

    The Cs-137 contamination of the soil in South Germany, especially around Schwabmuenchen, after the reactor accident in Chernobyl at the end of April 1986 amounted up to 20000 Bq/2. At certain places, maximum loads of even 40000 Bq/2 were measured. In the other South Bavarian regions and the southern parts of East Bavaria Cs-137 loads of between 5000-10000 Bq/2 were recorded which gradually declined to the North and to the West and reached values of <5000 Bq/2 in Lower Franconia. The regional distribution of the radiocaesium contamination in Bavarian game, especially deer, showed in the time from May to June for the area south of the Danube a 3.4 times higher contamination with Cs-137 and Cs-134 as compared to the North-Bavarian regions. By the end of July, the activities in South Bavaria were reduced to 756 Bq Cs-137/kg venison as compared to 2020 Bq/kg in May and June. In North Bavaria the values amounted to 239 Bq as compared to 591 Bq Cs-137/kg venison. From September onwards, the rise in Cs-137 activities in venison could be attributed to the feeding plants. (ECB)

  15. Nuclear reactor container

    International Nuclear Information System (INIS)

    A gas containing vessel has a water pool which is in communication with a dry well containing a reactor pressure vessel by way of a communication pipe is disposed. A capacity of a gas phase portion of the gas containing chamber, a capacity of the dry well, a water depth of a bent tube communicating the dry well with a pressure suppression pool of a pressure suppression chamber and a water depth of the communication pipe are determined so as to satisfy specific conditions. Since the water depth of the communication pipe is less than the water depth of the bent tube, incondensible gases and steams in the dry well flow into the water pool of the gas containing chamber at the initial stage of loss of coolant accident. Subsequently, steams in the dry well flow into the pressure suppression pool of the pressure suppression chamber by way of the bent tube. Accordingly, since the incondensible gases in the dry well do not flow into the pressure suppression chamber, pool swelling phenomenon in the pressure suppression chamber is not caused even if the water depth of the bent tube which leads to the pressure suppression chamber is great. Further, pressure increase due to transfer of the incondensible gases is decreased. (I.N.)

  16. Nuclear reactor safety

    International Nuclear Information System (INIS)

    Dr. Buhl feels that nuclear-energy issues are too complex to be understood as single topics, and can only be understood in relationship to broader issues. In fact, goals and risks associated with all energy options must be seen as interrelated with other broad issues, and it should be understood that there are presently no clearcut criteria to ensure that the best decisions are made. The technical community is responsible for helping the public to understand the basic incompatibility of hard and soft technologies and that there is no risk-free energy source. Four principles are outlined for assessing the risks of various energy technologies: (1) take a holistic view; (2) compare the risk with the unit energy output; (3) compare the risk with those of everyday activities; and (4) identify unusual risks associated with a particular option. Dr. Buhl refers to the study conducted by Dr. Inhaber of Canada who used this approach and concluded that nuclear power and natural gas have the lowest overall risk

  17. Three dimensional diffusion calculations of nuclear reactors

    International Nuclear Information System (INIS)

    This work deals with the three dimensional calculation of nuclear reactors using the code TRITON. The purposes of the work were to perform three-dimensional computations of the core of the Soreq nuclear reactor and of the power reactor ZION and to validate the TRITON code. Possible applications of the TRITON code in Soreq reactor calculations and in power reactor research are suggested. (H.K.)

  18. After Chernobyl. Possibilities of phasing out nuclear power in Sweden

    International Nuclear Information System (INIS)

    According to the currently applicable Parliamentary decision, the phasing out of nuclear power in Sweden must be completed by the year 2010. The National Energy Administration has analyzed the following questions. If it were to become evident that operating several or all of the Swedish nuclear power plants entailed serious risks, what possibilities would there be of phasing them out in the short term or over a longer period. And what would the consequences be with regard to the national economy and the environment? First we report the consequences of a rapid phase-out. Here, it is assumed that several or all nuclear plants would be taken out of operation within a period of two years. Available compensatory resources would be limited to more intensive utilization of existing hydropower, back-pressure plants, combined power and heating plants and oil-fired plants. The second alternative is a phase-out in ten years. Moreover, a case is discussed in which phase-out is planned and implemented from 1987 to 2005. Such a plan would provide industry more time to adjust, while a number of alternative techniques and fuels could be used to replace nuclear power. The consequences of the different phase-out alternatives can be described only within a framework of certain assumptions regarding the worldwide development. Important factors here include fuel prices and economic trends. Environmental restrictions comprise another important prerequisite

  19. The Chernobyl case: its repercussions on the International System on Civil Liability for Nuclear Damages

    International Nuclear Information System (INIS)

    With the discovery of the Nuclear Energy the world has been development her life the present investigation is based in the accident of the one of the most important Nuclear Power Plant in the world, situated in the Union of Socialist Sovietic Republics. The Nuclear Power Plant of Chernobyl. Us found in the investigation what not exist one legislation agree with the needs of development of the actual world in matter of the liability civil in case of the nuclear accidents. Found only the Convention of the Vienna. the Convention of the Brussels the which only cover the transportation the Nuclear substances in ships and others transportation medios. The complementary a the convention of the Paris and actually The Communication in case of the nuclear accidents and radiological accidents. In the present work think what the Community International haven the needs of created one legislation with character international what can help a the many countries what have Nuclear Power Plants, on all for protection of the her habitants. The International Atomic Energy Agency together with the International Justice Court and the United Nations Organization (U.N.O.) aplicated the law in matter of the nuclear accidents derivates of the liability responsibility in the use of the Nuclear Plants for elaboration the Electrical Energy or for Investigation in matter the nuclear energy both with identical responsibility civil in case the nuclear accident. (Author)

  20. Reactors for nuclear electric propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Buden, D.; Angelo, J.A. Jr.

    1981-01-01

    Propulsion is the key to space exploitation and power is the key to propulsion. This paper examines the role of nuclear fission reactors as the primary power source for high specific impulse electric propulsion systems for space missions of the 1980s and 1990s. Particular mission applications include transfer to and a reusable orbital transfer vehicle from low-Earth orbit to geosynchronous orbit, outer planet exploration and reconnaissance missions, and as a versatile space tug supporting lunar resource development. Nuclear electric propulsion is examined as an indispensable component in space activities of the next two decades.

  1. Reactors for nuclear electric propulsion

    International Nuclear Information System (INIS)

    Propulsion is the key to space exploitation and power is the key to propulsion. This paper examines the role of nuclear fission reactors as the primary power source for high specific impulse electric propulsion systems for space missions of the 1980s and 1990s. Particular mission applications include transfer to and a reusable orbital transfer vehicle from low-Earth orbit to geosynchronous orbit, outer planet exploration and reconnaissance missions, and as a versatile space tug supporting lunar resource development. Nuclear electric propulsion is examined as an indispensable component in space activities of the next two decades

  2. Gas-cooled nuclear reactor

    International Nuclear Information System (INIS)

    The gas temperature of a hot gas loop in gas-cooled nuclear reactor plants shall be able to be modified without influencing the gas temperature of the other loops. If necessary, it should be possible to stop the loop. This is possible by means of a mixer which is places below the heat absorbing component in the hot channel and which is connected to a cold gas line. (orig.)

  3. Research nuclear reactor operation management

    International Nuclear Information System (INIS)

    Some aspects of reactor operation management are highlighted. The main mission of the operational staff at a testing reactor is to operate it safely and efficiently, to ensure proper conditions for different research programs implying the use of the reactor. For reaching this aim, there were settled down operating plans for every objective, and procedure and working instructions for staff training were established, both for the start-up and for the safe operation of the reactor. Damages during operation or special situations which can arise, at stop, start-up, maintenance procedures were thoroughly considered. While the technical skill is considered to be the most important quality of the staff, the organising capacity is a must in the operation of any nuclear facility. Staff training aims at gaining both theoretical and practical experience based on standards about staff quality at each work level. 'Plow' sheet has to be carefully done, setting clear the decision responsibility for each person so that everyone's own technical level to be coupled to the problems which implies his responsibility. Possible events which may arise in operation, e.g., criticality, irradiation, contamination, and which do not arise in other fields, have to be carefully studied. One stresses that the management based on technical and scientific arguments have to cover through technical, economical and nuclear safety requirements a series of interlinked subprograms. Every such subprograms is subject to some peculiar demands by the help of which the entire activity field is coordinated. Hence for any subprogram there are established the objectives to be achieved, the applicable regulations, well-defined responsibilities, training of the personnel involved, the material and documentation basis required and activity planning. The following up of positive or negative responses generated by experiments and the information synthesis close the management scope. Important management aspects

  4. 15 years after Chernobyl, nuclear power plant safety improved world-wide, but regional strains on health, economy and environment remain

    International Nuclear Information System (INIS)

    Fifteen years after the Chernobyl accident, exhaustive studies by the IAEA and others provide a solid understanding of the causes and consequences of the accident, which stemmed from design deficiencies in the reactor compounded by violation of operating procedures. These deficiencies and the lack of an international notification mechanism led to the speedy adoption of early Notification and Assistance Conventions as well as later establishment of the landmark Convention on Nuclear Safety. Lessons learned from the accident were also a significant driving force behind a decade of IAEA assistance to the countries of Central and eastern Europe and the Former Soviet Union. Much of this work was focused on identifying the weaknesses in and improving the design safety of WWER and RBMK reactors

  5. An observation report on the late effects of the disaster of the Chernobyl nuclear power plant

    International Nuclear Information System (INIS)

    As part of international medical cooperation for the Chernobyl nuclear power plant accident, the authors participated in four fact-finding surveys for the aftermath in May 1990, and May, June, and July 1991. This report gives an outline of the surveys, with the purpose of providing the basic information for the future countermeasures. The focus of this paper is on medical surveys for hematopoietic disease (mainly leukemia), infantile thyroid abnormality, and congenital abnormality. In 8 children undergoing hematopoietic examination, accumulated exposure doses were all one rad or less. Infantile leukemia is discussed in terms of exposure doses, radioactivity, radiation-related leukemic types, and the future management. The results of thyroid examination performed in 40 persons at a hospital in the Ukraine are presented: 17 persons were noted to have sclerosing struma associated with atrophy. Incidence of thyroid cancer, presented from two facilities of the Ukraine and four facilities of the Belorussia, is reported. Thyroid abnormality is discussed in terms of radioiodine, I-131 treatment in Basedow's disease, Bikini nuclear exlosion, Hiroshima and Nagasaki A-bomb survivors, and Chernobyl pediatric survivors. The final topic, congenital abnormality, covers the information on fetal and neonatal death and the occurrence of anomaly obtained from reliable physicians in the Belorussia, and is discussed in terms of exposure doses. Finally, problems encountered in surveys for the aftermath are also mentioned. (N.K.)

  6. Worldwide advanced nuclear power reactors with passive and inherent safety: What, why, how, and who

    International Nuclear Information System (INIS)

    The political controversy over nuclear power, the accidents at Three Mile Island (TMI) and Chernobyl, international competition, concerns about the carbon dioxide greenhouse effect and technical breakthroughs have resulted in a segment of the nuclear industry examining power reactor concepts with PRIME safety characteristics. PRIME is an acronym for Passive safety, Resilience, Inherent safety, Malevolence resistance, and Extended time after initiation of an accident for external help. The basic ideal of PRIME is to develop power reactors in which operator error, internal sabotage, or external assault do not cause a significant release of radioactivity to the environment. Several PRIME reactor concepts are being considered. In each case, an existing, proven power reactor technology is combined with radical innovations in selected plant components and in the safety philosophy. The Process Inherent Ultimate Safety (PIUS) reactor is a modified pressurized-water reactor, the Modular High Temperature Gas-Cooled Reactor (MHTGR) is a modified gas-cooled reactor, and the Advanced CANDU Project is a modified heavy-water reactor. In addition to the reactor concepts, there is parallel work on super containments. The objective is the development of a passive ''box'' that can contain radioactivity in the event of any type of accident. This report briefly examines: why a segment of the nuclear power community is taking this new direction, how it differs from earlier directions, and what technical options are being considered. A more detailed description of which countries and reactor vendors have undertaken activities follows. 41 refs

  7. Feasibility of studies on health effects in western Europe due to the reactor accident at Chernobyl and Recommendations for research

    International Nuclear Information System (INIS)

    The report considers whether studies of health effects related to the radioactive contamination of western Europe caused by the releases from the Chernobyl reactor accident would be useful. The report evaluates the exposure patterns and the dose levels within the European Community, the different health effects that might be induced by such doses, and the likelihood that epidemiological studies could produce scientifically useful information. The report concludes that at the exposure levels experienced in the European Community the study of post-Chernobyl cancer rates in adults and the study of heritable genetic effects in the offspring of those exposed would be unproductive. It also concludes that even a study of childhood cancer following in utero exposure would be unlikely to demonstrate any attributable increase in risk. However, the report recommends that a small epidemiologic survey of childhood cancer be conducted within areas where selected cancer registration was in existence at the time of the Chernobyl accident to check the ability to predict risks from doses of the order received, to contribute to the understanding of the occurrence of childhood leukemia and to allay public anxiety

  8. Exporting apocalypse: CANDU reactors and nuclear proliferation

    International Nuclear Information System (INIS)

    The author believes that the peaceful use of nuclear technology leads inevitably to the production of nuclear weapons, and that CANDU reactors are being bought by countries that are likely to build bombs. He states that exports of reactors and nuclear materials cannot be defended and must be stopped

  9. distribution of Release Fission Products Through the Nuclear Reactor Site

    International Nuclear Information System (INIS)

    Through the operation of nuclear reactors, radioactive fission products could be release to the environment as a result of severe accidents e.g. Chernobyl accident. Estimation of the atmospheric dispersion, distribution and transport of the radioactive fission products is essential to assessment of the risk to the public from such accidents. In this work, the polluted plume is treated as a matrix of isolated particles.These particles are the fission product isotopes, which compose the radioactive plume.The fission products were classified depending on its half live into three category, long-lived, medium lived and small half-life.The normalized concentrations of the fission product isotopes in the radioactive plume were calculated.The travel time (the time elapsed from the released instant till the deposited time) of each fission products was calculated. The area around the nuclear reactor stack was divided into different zones, started from the reactor stack position until 5 km.The deposited radioactive fission products in each zone was estimated.The calculations were done using the spherical Gaussian plume model

  10. Artificial intelligence in nuclear reactor operation

    International Nuclear Information System (INIS)

    Assessment of four real fuzzy control applications at the MIT research reactor in the US, the FUGEN heavy water reactor in Japan, the BR1 research reactor in Belgium, and a TRIGA Mark III reactor in Mexico will be examined through a SWOT analysis (strengths, weakness, opportunities, and threats). Special attention will be paid to the current cooperation between the Belgian Nuclear Research Centre (SCK·CEN) and the Mexican Nuclear Centre (ININ) on AI-based intelligent control for nuclear reactor operation under the partial support of the National Council for Science and Technology of Mexico (CONACYT). (authors)

  11. Heat for industry from nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kikoin, I.K.; Novikov, V.M.

    Two factors which incline nations toward the use of heat from nuclear reactors for industrial use are: 1) exhaustion of cheap fossil fuel resources, and 2) ecological problems associated both with extraction of fossil fuel from the earth and with its combustion. In addition to the usual problems that beset nuclear reactors, special problems associated with using heat from nuclear reactors in various industries are explored.

  12. Molten salts in nuclear reactors

    International Nuclear Information System (INIS)

    Collection of references dealing with the physicochemical studies of fused salts, in particular the alkali and alkali earth halides. Numerous binary, ternary and quaternary systems of these halides with those of uranium and thorium are examined, and the physical properties, density, viscosity, vapour pressure etc... going from the halides to the mixtures are also considered. References relating to the corrosion of materials by these salts are included and the treatment of the salts with a view to recuperation after irradiation in a nuclear reactor is discussed. (author)

  13. The application problems of nuclear reactors

    International Nuclear Information System (INIS)

    Latvia is surrounded by closely located nuclear reactors. In a distance of 1000 km from Latvia there are 62 working and 12 suspended high power nuclear reactors. Near the borders of Latvia, in the 3 km range four countries are exploiting 12 nuclear reactors, whose reliability and safe operation is always arousing profound interest in our community. On estimating the prospects of Latvian energetics we can conclude that at the beginning of the next century it will be extremely complicated task to supply our country with electricity and heat without nuclear reactors. This is due to lack of the domestic energy resources and to the necessity of reducing harmful pollutions of TECs. (authors)

  14. Autonomous Control of Space Nuclear Reactors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Nuclear reactors to support future robotic and manned missions impose new and innovative technological requirements for their control and protection...

  15. Nuclear reactor built, being built, or planned

    International Nuclear Information System (INIS)

    This document contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1990. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually from Washington headquarters and field offices of DOE, from the US Nuclear Regulatory Commission, from the US reactor manufacturers who are the principal nuclear contractors for foreign reactor locations, from US and foreign embassies, and from foreign governmental nuclear departments. The book is divided into three major sections: Section 1 consists of a reactor locator map and reactor tables; Section 2 includes nuclear reactors that are operating, being built, or planned; and Section 3 includes reactors that have been shut down permanently or dismantled. Sections 2 and 3 contain the following classification of reactors: Civilian, Production, Military, Export, and Critical Assembly

  16. Licensed reactor nuclear safety criteria applicable to DOE reactors

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    The Department of Energy (DOE) Order DOE 5480.6, Safety of Department of Energy-Owned Nuclear Reactors, establishes reactor safety requirements to assure that reactors are sited, designed, constructed, modified, operated, maintained, and decommissioned in a manner that adequately protects health and safety and is in accordance with uniform standards, guides, and codes which are consistent with those applied to comparable licensed reactors. This document identifies nuclear safety criteria applied to NRC (Nuclear Regulatory Commission) licensed reactors. The titles of the chapters and sections of USNRC Regulatory Guide 1.70, Standard Format and Content of Safety Analysis Reports for Nuclear Power Plants, Rev. 3, are used as the format for compiling the NRC criteria applied to the various areas of nuclear safety addressed in a safety analysis report for a nuclear reactor. In each section the criteria are compiled in four groups: (1) Code of Federal Regulations, (2) US NRC Regulatory Guides, SRP Branch Technical Positions and Appendices, (3) Codes and Standards, and (4) Supplemental Information. The degree of application of these criteria to a DOE-owned reactor, consistent with their application to comparable licensed reactors, must be determined by the DOE and DOE contractor.

  17. Licensed reactor nuclear safety criteria applicable to DOE reactors

    International Nuclear Information System (INIS)

    The Department of Energy (DOE) Order DOE 5480.6, Safety of Department of Energy-Owned Nuclear Reactors, establishes reactor safety requirements to assure that reactors are sited, designed, constructed, modified, operated, maintained, and decommissioned in a manner that adequately protects health and safety and is in accordance with uniform standards, guides, and codes which are consistent with those applied to comparable licensed reactors. This document identifies nuclear safety criteria applied to NRC [Nuclear Regulatory Commission] licensed reactors. The titles of the chapters and sections of USNRC Regulatory Guide 1.70, Standard Format and Content of Safety Analysis Reports for Nuclear Power Plants, Rev. 3, are used as the format for compiling the NRC criteria applied to the various areas of nuclear safety addressed in a safety analysis report for a nuclear reactor. In each section the criteria are compiled in four groups: (1) Code of Federal Regulations, (2) US NRC Regulatory Guides, SRP Branch Technical Positions and Appendices, (3) Codes and Standards, and (4) Supplemental Information. The degree of application of these criteria to a DOE-owned reactor, consistent with their application to comparable licensed reactors, must be determined by the DOE and DOE contractor

  18. A Comparison of the Effects of the Chernobyl and Three Mile Island Nuclear Accidents on the U.S. Electric Utility Industry

    OpenAIRE

    AKTAR, İsmail

    2005-01-01

    We examined the stock market reaction to two nuclear accidents, the Three Mile Island incident and the Chernobyl disaster. We were interested in determining whether the negative stock market reaction following these events was consistently related to the level of nuclear exposure by each firm and whether the negative reaction was reasonably linked to human safety concerns. Prior research has shown that following TMI, but anomalously not Chernobyl, firms with the more nuclear capacity experien...

  19. Radiation contamination after the Chernobyl nuclear accident and the effective dose received by the population of Croatia

    International Nuclear Information System (INIS)

    Because of the Chernobyl nuclear accident which led to enhanced deposition of all fission products, contamination of the human environment in the Republic of Croatia was much higher than in the previous two decades. The paper deals with the investigation of deposition and contamination by fission product radionuclides (137Cs and 90Sr, in particular), especially within the human food chain. Its aim was to determine differences in contamination levels resulting from the Chernobyl accident and from large-scale atmospheric nuclear weapon tests. For the year following the Chernobyl accident, the radiation doses received from external and internal exposures were estimated for 1-year old infants, children at the age of 10-years and adults. The corresponding annual effective doses were 1·49, 0·93 and 0·83 mSv, respectively. The paper also gives data on the yearly intakes of 137Cs and 90Sr in foods and the corresponding effective doses received by the population of Croatia over many years from the global fallout following nuclear weapons testing and the Chernobyl accident. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  20. Chernobyl, 16 years later

    International Nuclear Information System (INIS)

    This document on the Chernobyl site evolution is constituted around four main questions. What about the future of the Chernobyl site, the damaged reactor and the ''sarcophagus'' constructed around the reactor? What about the sanitary consequences of the accident on the liquidators asked to blot out the radiation and the around people exposed to radiation? What about the contaminated land around the power plant and their management? Concerning the France, what were the ''radioactive cloud'' sanitary consequences? (A.L.B.)

  1. Origin of a signal detected with the LSD detector after the accident at the chernobyl nuclear power plant

    Science.gov (United States)

    Agafonova, N. Yu.; Malgin, A. S.; Fulgione, W.

    2013-08-01

    A rare signal was detected at 23:53 Moscow time on April 27, 1986 with the LSD low-background scintillation detector located under Mont Blanc at a distance of 1820 km from Chernobyl. To reveal the origin of this signal, we discuss the results obtained with other instruments operating within a similar program, as well as analyze the characteristics of the pulses of the signal and facts referring to the explosion of the Chernobyl reactor. A hypothesis based on detection with the LSD of gamma-quanta from β decays of 135I nuclei ejected into atmosphere by the reactor explosion and carried in the underground detector camera with air of positive ventilation is considered. The explosion origin of the LSD signal indicates a new technogenic source of the background in the search for neutrino bursts from cores of collapsing stars.

  2. Origin of a signal detected with the LSD detector after the accident at the chernobyl nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Agafonova, N. Yu., E-mail: natagafonova@gmail.com; Malgin, A. S., E-mail: malgin@lngs.infn.it [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation); Fulgione, W. [Istituto Nazionale di Fisica Nucleare, and Osservatorio Astrofisico di Torino, Istituto di Fisica dello Spazio Interplanetario (Italy)

    2013-08-15

    A rare signal was detected at 23:53 Moscow time on April 27, 1986 with the LSD low-background scintillation detector located under Mont Blanc at a distance of 1820 km from Chernobyl. To reveal the origin of this signal, we discuss the results obtained with other instruments operating within a similar program, as well as analyze the characteristics of the pulses of the signal and facts referring to the explosion of the Chernobyl reactor. A hypothesis based on detection with the LSD of gamma-quanta from {beta} decays of {sup 135}I nuclei ejected into atmosphere by the reactor explosion and carried in the underground detector camera with air of positive ventilation is considered. The explosion origin of the LSD signal indicates a new technogenic source of the background in the search for neutrino bursts from cores of collapsing stars.

  3. Licensed reactor nuclear safety criteria applicable to DOE reactors

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    This document is a compilation and source list of nuclear safety criteria that the Nuclear Regulatory Commission (NRC) applies to licensed reactors; it can be used by DOE and DOE contractors to identify NRC criteria to be evaluated for application to the DOE reactors under their cognizance. The criteria listed are those that are applied to the areas of nuclear safety addressed in the safety analysis report of a licensed reactor. They are derived from federal regulations, USNRC regulatory guides, Standard Review Plan (SRP) branch technical positions and appendices, and industry codes and standards.

  4. Licensed reactor nuclear safety criteria applicable to DOE reactors

    International Nuclear Information System (INIS)

    This document is a compilation and source list of nuclear safety criteria that the Nuclear Regulatory Commission (NRC) applies to licensed reactors; it can be used by DOE and DOE contractors to identify NRC criteria to be evaluated for application to the DOE reactors under their cognizance. The criteria listed are those that are applied to the areas of nuclear safety addressed in the safety analysis report of a licensed reactor. They are derived from federal regulations, USNRC regulatory guides, Standard Review Plan (SRP) branch technical positions and appendices, and industry codes and standards

  5. Proliferation Resistant Nuclear Reactor Fuel

    International Nuclear Information System (INIS)

    Global appetite for fission power is projected to grow dramatically this century, and for good reason. Despite considerable research to identify new sources of energy, fission remains the most plentiful and practical alternative to fossil fuels. The environmental challenges of fossil fuel have made the fission power option increasingly attractive, particularly as we are forced to rely on reserves in ecologically fragile or politically unstable corners of the globe. Caught between a globally eroding fossil fuel reserve as well as the uncertainty and considerable costs in the development of fusion power, most of the world will most likely come to rely on fission power for at least the remainder of the 21st century. Despite inevitable growth, fission power faces enduring challenges in sustainability and security. One of fission power's greatest hurdles to universal acceptance is the risk of potential misuse for nefarious purposes of fissionable byproducts in spent fuel, such as plutonium. With this issue in mind, we have discussed intrinsic concepts in this report that are motivated by the premise that the utility, desirability, and applicability of nuclear materials can be reduced. In a general sense, the intrinsic solutions aim to reduce or eliminate the quantity of existing weapons usable material; avoid production of new weapons-usable material through enrichment, breeding, extraction; or employ engineering solutions to make the fuel cycle less useful or more difficult for producing weapons-usable material. By their nature, these schemes require modifications to existing fuel cycles. As such, the concomitants of these modifications require engagement from the nuclear reactor and fuel-design community to fully assess their effects. Unfortunately, active pursuit of any scheme that could further complicate the spread of domestic nuclear power will probably be understandably unpopular. Nevertheless, the nonproliferation and counterterrorism issues are paramount, and

  6. The lesson of the Chernobyl disaster

    Energy Technology Data Exchange (ETDEWEB)

    Milhaud, G. (Hopital Saint-Antoine, 75 Paris (FR))

    1991-01-01

    On april 26, 1986 a major nuclear disaster took place at 1 h 24 min local time, destroying the fourth reactor of the Chernobyl plant. Five years later the consequences of the disaster are still not fully known. Nevertheless the long term future of nuclear energy in the world is uncertain. Questions need to be answered by observing hard facts if emotional attitudes are not to prevail over reality. The reactor and its core were destroyed by an explosion, causing two radioactive jet emissions of iodine 131, followed by caesium 137. Both elements are mainly incorporated in the body via food. The Chernobyl disaster was a consequence of inadequate safety regulations and human error. Enforcement of strict regulations are likely to be highly effective in preventing a further catastrophe. However, governments should consider another possibility. What would be the consequences for public health if a terroristic act deliberately destroyed a nuclear power station.

  7. Problems of nuclear reactor safety. Vol. 1

    International Nuclear Information System (INIS)

    Proceedings of the 9. Topical Meeting 'Problems of nuclear reactor safety' are presented. Papers include results of studies and developments associated with methods of calculation and complex computerized simulation for stationary and transient processes in nuclear power plants. Main problems of reactor safety are discussed as well as rector accidents on operating NPP's are analyzed

  8. The Design of a Nuclear Reactor

    Indian Academy of Sciences (India)

    2016-09-01

    The aim of this largely pedagogical article is toemploy pre-college physics to arrive at an understanding of a system as complex as a nuclear reactor. We focus on three key issues: the fuelpin, the moderator, and lastly the dimensions ofthe nuclear reactor.

  9. Chernobyl bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Carr, F. Jr.; Mahaffey, J.A.

    1989-09-01

    The purpose of the DOE/OHER Chernobyl Database project is to create and maintain an information system to provide usable information for research studies related to the nuclear accident. The system is the official United States repository for information about the Chernobyl accident and its consequences, and currently includes an extensive bibliography and diverse radiological measurements with supporting information. PNL has established two resources: original (not summarized) measurement data, currently about 80,000 measurements, with ancillary information; and about 2,200 bibliographic citations, some including abstracts. Major organizations that have contributed radiological measurement data include the Washington State Department of Social and Health Services; United States Environmental Protection Agency (domestic and foreign data); United States Nuclear Regulatory Commission; Stone Webster; Brookhaven National Laboratory; Commissariat A L'energie Atomique in France; Ministry of Agriculture, Fisheries, and Food in the United Kingdom; Japan National Institute of Radiological Sciences; and the Finnish Centre For Radiation and Nuclear Safety (STUK). Scientists in Australia, Austria, Belgium, Canada, China, Denmark, England, Federal Republic of Germany, Finland, France, Ireland, Italy, Japan, the Netherlands, Romania, Scotland, Spain, Sweden, Switzerland, United States, Wales, and Yugoslavia have made contributions. Bibliographic materials have been obtained from scientists in the above countries that have replied to requests. In addition, literature searches have been conducted, including a search of the DOE Energy Database. The last search was conducted in January, 1989. This document lists the bibliographic information in the DOE/OHER Chernobyl Database at the current time.

  10. Chernobyl bibliography

    International Nuclear Information System (INIS)

    The purpose of the DOE/OHER Chernobyl Database project is to create and maintain an information system to provide usable information for research studies related to the nuclear accident. The system is the official United States repository for information about the Chernobyl accident and its consequences, and currently includes an extensive bibliography and diverse radiological measurements with supporting information. PNL has established two resources: original (not summarized) measurement data, currently about 80,000 measurements, with ancillary information; and about 2,200 bibliographic citations, some including abstracts. Major organizations that have contributed radiological measurement data include the Washington State Department of Social and Health Services; United States Environmental Protection Agency (domestic and foreign data); United States Nuclear Regulatory Commission; Stone ampersand Webster; Brookhaven National Laboratory; Commissariat A L'energie Atomique in France; Ministry of Agriculture, Fisheries, and Food in the United Kingdom; Japan National Institute of Radiological Sciences; and the Finnish Centre For Radiation and Nuclear Safety (STUK). Scientists in Australia, Austria, Belgium, Canada, China, Denmark, England, Federal Republic of Germany, Finland, France, Ireland, Italy, Japan, the Netherlands, Romania, Scotland, Spain, Sweden, Switzerland, United States, Wales, and Yugoslavia have made contributions. Bibliographic materials have been obtained from scientists in the above countries that have replied to requests. In addition, literature searches have been conducted, including a search of the DOE Energy Database. The last search was conducted in January, 1989. This document lists the bibliographic information in the DOE/OHER Chernobyl Database at the current time

  11. Observations on the geology and geohydrology of the Chernobyl' nuclear accident site, Ukraine

    Science.gov (United States)

    Matzko, J.R.; Percious, D.J.; Rachlin, J.; Marples, D.R.

    1994-01-01

    The most highly contaminated surface areas from cesium-137 fallout from the April 1986 accident at the Chernobyl' nuclear power station in Ukraine occur within the 30-km radius evacuation zone set up around the station, and an 80-km lobe extending to the west-southwest. Lower levels of contamination extend 300 km to the west of the power station. The geology, the presence of surface water, a shallow water table, and leaky aquifers at depth make this an unfavorable environment for the long-term containment and storage of the radioactive debris. An understanding of the general geology and hydrology of the area is important to assess the environmental impact of this unintended waste storage site, and to evaluate the potential for radionuclide migration through the soil and rock and into subsurface aquifers and nearby rivers. -from Authors

  12. Cytogenetic features of leukaemias diagnosed in residents of areas contaminated after the Chernobyl nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Domracheva, E.V. E-mail: dom@blood.ru; Aseeva, E.A.; Obukhova, T.N.; Kobzev, Y.N.; Olshanskaya, Y.V.; D' achenko, L.V.; Udovichenko, A.I.; Zakharova, A.V.; Milyutina, G.I.; Nechai, V.V.; Vorobiov, A.I

    2000-05-15

    A comparison of chromosomal abnormalities in bone marrow leukaemic cells and of stable and unstable aberrations in lymphocytes of patients with hematological malignancies who live in areas with or without contamination by the Chernobyl nuclear accident has been made using FISH and G-banding. Healthy residents of these areas comprised the control group. No systematic cytogenetic differences of leukaemic cells between patients from contaminated and uncontaminated areas were observed. Lymphocyte aberrations, however, were generally higher in all subjects from contaminated areas. Comparison has been made with specific cytogenetic features of leukaemic cells and a high level of stable aberrations in lymphocytes of patients with secondary leukaemias that had developed after chemo- and/or radio-therapy.

  13. Nuclear spectroscopy and electron microprobe study of a Ba hot particle originating from the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Vapirev, E.I.; Bourin, K.I.; Hristova, A.V.; Gourev, V. (Sofia Univ. (Bulgaria). Fizicheski Fakultet); Tsacheva, Ts. (Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. of Physical Chemistry); Kamenova, Ts. (Bylgarska Akademiya na Naukite, Sofia (Bulgaria). Inst. po Metaloznanie i Tekhnologiya na Metalite)

    1994-01-01

    A Ba-Sr hot particle released during the Chernobyl accident has been studied by electron microprobe analysis and alpha, beta and gamma spectroscopy. The Ba-Sr hot particle proved in terms of mass to be a Zr hot particle. It has been concluded that the Zr has a nuclear origin through the chain Br-Kr-Rb-Sr-Y-Zr. The estimated specific activity is approximately 1.8 [+-] 0.5 Bq.[mu]m[sup -3] which is comparable to the estimated activity of [approx] 1 Bq.[mu]m[sup -3] of the UO[sub 2] hot particles. The conclusions with reference to the risk when such a particle is inhaled is that the risk of a Ba-Sr-Zr hot particle is not greater than the risk due to standard UO[sub 2] hot particles. (author).

  14. "What--me worry?" "Why so serious?": a personal view on the Fukushima nuclear reactor accidents.

    Science.gov (United States)

    Gallucci, Raymond

    2012-09-01

    Infrequently, it seems that a significant accident precursor or, worse, an actual accident, involving a commercial nuclear power reactor occurs to remind us of the need to reexamine the safety of this important electrical power technology from a risk perspective. Twenty-five years since the major core damage accident at Chernobyl in the Ukraine, the Fukushima reactor complex in Japan experienced multiple core damages as a result of an earthquake-induced tsunami beyond either the earthquake or tsunami design basis for the site. Although the tsunami itself killed tens of thousands of people and left the area devastated and virtually uninhabitable, much concern still arose from the potential radioactive releases from the damaged reactors, even though there was little population left in the area to be affected. As a lifelong probabilistic safety analyst in nuclear engineering, even I must admit to a recurrence of the doubt regarding nuclear power safety after Fukushima that I had experienced after Three Mile Island and Chernobyl. This article is my attempt to "recover" my personal perspective on acceptable risk by examining both the domestic and worldwide history of commercial nuclear power plant accidents and attempting to quantify the risk in terms of the frequency of core damage that one might glean from a review of operational history.

  15. Nuclear reactor internals alignment configuration

    Science.gov (United States)

    Gilmore, Charles B.; Singleton, Norman R.

    2009-11-10

    An alignment system that employs jacking block assemblies and alignment posts around the periphery of the top plate of a nuclear reactor lower internals core shroud to align an upper core plate with the lower internals and the core shroud with the core barrel. The distal ends of the alignment posts are chamfered and are closely received within notches machined in the upper core plate at spaced locations around the outer circumference of the upper core plate. The jacking block assemblies are used to center the core shroud in the core barrel and the alignment posts assure the proper orientation of the upper core plate. The alignment posts may alternately be formed in the upper core plate and the notches may be formed in top plate.

  16. Classification of hot particles from the Chernobyl accident and nuclear weapons detonations by non-destructive methods

    International Nuclear Information System (INIS)

    Both after the Chernobyl accident and nuclear weapon detonations, agglomerates of radioactive material, so-called hot particles, were released or formed which show a behaviour in the environment quite different from the activity released in gaseous or aerosol form. The differences in their characteristic properties, in the radionuclide composition and the uranium and actinide contents are described in detail for these particles. While nuclear bomb hot particles (both from fission and fusion bombs) incorporate well detectable trace amounts of 60Co and 152Eu, these radionuclides are absent in Chernobyl hot particles. In contrast, Chernobyl hot particles contain 125Sb and 144Ce which are absent in atomic bomb HPs. Obvious differences are also observable between fusion and fission bombs' hot particles (significant differences in 152Eu/155Eu, 154Eu/155Eu and 238Pu/239Pu ratios) which facilitate the identification of HPs of unknown provensence. The ratio of 239Pu/240Pu in Chernobyl hot particles could be determined by a non-destructive method at 1:1.5. A non-destructive method to determine the content of non-radioactive elements by Kα-emission measurements was developed by which inactive Zr, Nb, Fe and Ni could be verified in the particles

  17. Nuclear reactor safety research in Kazakhstan

    International Nuclear Information System (INIS)

    Full text : The paper summarizes activities being implemented by the National Nuclear Center of the Republic of Kazakhstan in support of safe operation of nuclear reactors; shows its crucial efforts and further road map in this line. As is known, the world community considers nuclear reactor safety as one of the urgent research areas. Kazakhstan has been pursuing studies in support of nuclear energy safety since early 80s. The findings allow to coordinate available computational methods and design new ones while validating new NPP Projects and making analysis for reactor installations available

  18. The Italian debate on nuclear energy in the post Chernobyl age

    International Nuclear Information System (INIS)

    Full text of publication follows: Italy entered with enthusiasm into the production of nuclear energy for civil use at the end of 50. By 1966 - with an overall output of 3.9 billions kWh - Italy had become the fourth world producer of electricity generated by nuclear reactions, the second one in Europe after Great Britain. Chernobyl's 1986 disaster, which so much shook public opinion all over Europe, had particularly important economic and political consequences in Italy. In a controversial referendum, held in November 1987, Italian citizens voted for the repeal of three laws which promoted the installation of nuclear power plants on the Italian soil and the participation of ENEL (National Institution for the Electrical Energy) to plant constructions abroad. The 1987 referendum was interpreted by the Italian government as an opposition to nuclear power generation - the following year, the four Italian plants (Garigliano, Latina, Trino Vercellese, Caorso) ceased their activity and plans to build new plants were abandoned. This decision marked the ruin of Italian research on nuclear energy, that in the 30 had known a glorious era thanks to Enrico Fermi works. As the 20. Anniversary of Chernobyl's accident is drawing near, the University of Milan and ICS-research group (Innovations in Communication of Science) at SISSA, Trieste, have decided to analyse jointly the reasons which brought Italy to give up its nuclear energy production. In the present scenario of controversies concerning the development of science and technology, in which European countries exchange experiences of best practice to involve the public in decision making processes, Italy reaction to Chernobyl accident can indeed be considered paradigmatic in that it anticipated crucial risks governance issues in today relationship between science and society. The research project draws on methodologies used in media studies and on socio linguistic analysis, as developed by risk perception and risk

  19. Daddy, What's a Nuclear Reactor?

    International Nuclear Information System (INIS)

    No matter what we think of the nuclear industry, it is part of mankind's heritage. The decommissioning process is slowly making facilities associated with this industry disappear and not enough is being done to preserve the information for future generations. This paper provides some food for thought and provides a possible way forward. Industrial archaeology is an ever expanding branch of archaeology that is dedicated to preserving, interpreting and documenting our industrial past and heritage. Normally it begins with analyzing an old building or ruins and trying to determine what was done, how it was done and what changes might have occurred during its operation. We have a unique opportunity to document all of these issues and provide them before the nuclear facility disappears. Entombment is an acceptable decommissioning strategy; however we would have to change our concept of entombment. It is proposed that a number of nuclear facilities be entombed or preserved for future generations to appreciate. This would include a number of different types of facilities such as different types of nuclear power and research reactors, a reprocessing plant, part of an enrichment plant and a fuel manufacturing plant. One of the main issues that would require resolution would be that of maintaining information of the location of the buried facility and the information about its operation and structure, and passing this information on to future generations. This can be done, but a system would have to be established prior to burial of the facility so that no information would be lost. In general, our current set of requirements and laws may need to be re-examined and modified to take into account these new situations. As an alternative, and to compliment the above proposal, it is recommended that a study and documentation of the nuclear industry be considered as part of twentieth century industrial archaeology. This study should not only include the power and fuel cycle

  20. Nuclear reactor philosophy and criteria

    International Nuclear Information System (INIS)

    Nuclear power plant safety criteria and principles developed in Canada are directed towards minimizing the chance of failure of the fuel and preventing or reducing to an acceptably low level the escape of fission products should fuel failure occur. Safety criteria and practices are set forth in the Reactor Siting Guide, which is based upon the concept of defence in depth. The Guide specifies that design and construction shall follow the best applicable code, standard or practice; the total of all serious process system failures shall not exceed one in three years; special safety systems are to be physically and functionally separate from process systems and each other; and safety systems shall be testable, with unavailability less than 10-3. Doses to the most exposed member of the public due to normal operation, serious process failures, and dual failures are specified. Licensees are also required to consider the effects of extreme conditions due to airplane crashes, explosions, turbine disintegration, pipe burst, and natural disasters. Safety requirements are changing as nuclear power plant designs evolve and in response to social and economic pressures

  1. Nuclear waste management, reactor decommisioning, nuclear liability and public attitudes

    International Nuclear Information System (INIS)

    This paper deals with several issues that are frequently raised by the public in any discussion of nuclear energy, and explores some aspects of public attitudes towards nuclear-related activities. The characteristics of the three types of waste associated with the nuclear fuel cycle, i.e. mine/mill tailings, reactor wastes and nuclear fuel wastes, are defined, and the methods currently being proposed for their safe handling and disposal are outlined. The activities associated with reactor decommissioning are also described, as well as the Canadian approach to nuclear liability. The costs associated with nuclear waste management, reactor decommissioning and nuclear liability are also discussed. Finally, the issue of public attitudes towards nuclear energy is addressed. It is concluded that a simple and comprehensive information program is needed to overcome many of the misconceptions that exist about nuclear energy and to provide the public with a more balanced information base on which to make decisions

  2. Proliferation Resistant Nuclear Reactor Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Gray, L W; Moody, K J; Bradley, K S; Lorenzana, H E

    2011-02-18

    Global appetite for fission power is projected to grow dramatically this century, and for good reason. Despite considerable research to identify new sources of energy, fission remains the most plentiful and practical alternative to fossil fuels. The environmental challenges of fossil fuel have made the fission power option increasingly attractive, particularly as we are forced to rely on reserves in ecologically fragile or politically unstable corners of the globe. Caught between a globally eroding fossil fuel reserve as well as the uncertainty and considerable costs in the development of fusion power, most of the world will most likely come to rely on fission power for at least the remainder of the 21st century. Despite inevitable growth, fission power faces enduring challenges in sustainability and security. One of fission power's greatest hurdles to universal acceptance is the risk of potential misuse for nefarious purposes of fissionable byproducts in spent fuel, such as plutonium. With this issue in mind, we have discussed intrinsic concepts in this report that are motivated by the premise that the utility, desirability, and applicability of nuclear materials can be reduced. In a general sense, the intrinsic solutions aim to reduce or eliminate the quantity of existing weapons usable material; avoid production of new weapons-usable material through enrichment, breeding, extraction; or employ engineering solutions to make the fuel cycle less useful or more difficult for producing weapons-usable material. By their nature, these schemes require modifications to existing fuel cycles. As such, the concomitants of these modifications require engagement from the nuclear reactor and fuel-design community to fully assess their effects. Unfortunately, active pursuit of any scheme that could further complicate the spread of domestic nuclear power will probably be understandably unpopular. Nevertheless, the nonproliferation and counterterrorism issues are paramount

  3. Environmental Problems Associated With Decommissioning The Chernobyl Nuclear Power Plant Cooling Pond

    International Nuclear Information System (INIS)

    Decommissioning of nuclear power plants and other nuclear fuel cycle facilities has been an imperative issue lately. There exist significant experience and generally accepted recommendations on remediation of lands with residual radioactive contamination; however, there are hardly any such recommendations on remediation of cooling ponds that, in most cases, are fairly large water reservoirs. The literature only describes remediation of minor reservoirs containing radioactive silt (a complete closure followed by preservation) or small water reservoirs resulting in reestablishing natural water flows. Problems associated with remediation of river reservoirs resulting in flooding of vast agricultural areas also have been described. In addition, the severity of environmental and economic problems related to the remedial activities is shown to exceed any potential benefits of these activities. One of the large, highly contaminated water reservoirs that require either remediation or closure is Karachay Lake near the MAYAK Production Association in the Chelyabinsk Region of Russia where liquid radioactive waste had been deep well injected for a long period of time. Backfilling of Karachay Lake is currently in progress. It should be noted that secondary environmental problems associated with its closure are considered to be of less importance since sustaining Karachay Lake would have presented a much higher radiological risk. Another well-known highly contaminated water reservoir is the Chernobyl Nuclear Power Plant (ChNPP) Cooling Pond, decommissioning of which is planned for the near future. This study summarizes the environmental problems associated with the ChNPP Cooling Pond decommissioning.

  4. ENVIRONMENTAL PROBLEMS ASSOCIATED WITH DECOMMISSIONING THE CHERNOBYL NUCLEAR POWER PLANT COOLING POND

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E.

    2009-09-30

    Decommissioning of nuclear power plants and other nuclear fuel cycle facilities has been an imperative issue lately. There exist significant experience and generally accepted recommendations on remediation of lands with residual radioactive contamination; however, there are hardly any such recommendations on remediation of cooling ponds that, in most cases, are fairly large water reservoirs. The literature only describes remediation of minor reservoirs containing radioactive silt (a complete closure followed by preservation) or small water reservoirs resulting in reestablishing natural water flows. Problems associated with remediation of river reservoirs resulting in flooding of vast agricultural areas also have been described. In addition, the severity of environmental and economic problems related to the remedial activities is shown to exceed any potential benefits of these activities. One of the large, highly contaminated water reservoirs that require either remediation or closure is Karachay Lake near the MAYAK Production Association in the Chelyabinsk Region of Russia where liquid radioactive waste had been deep well injected for a long period of time. Backfilling of Karachay Lake is currently in progress. It should be noted that secondary environmental problems associated with its closure are considered to be of less importance since sustaining Karachay Lake would have presented a much higher radiological risk. Another well-known highly contaminated water reservoir is the Chernobyl Nuclear Power Plant (ChNPP) Cooling Pond, decommissioning of which is planned for the near future. This study summarizes the environmental problems associated with the ChNPP Cooling Pond decommissioning.

  5. Environmental Problems Associated With Decommissioning The Chernobyl Nuclear Power Plant Cooling Pond

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E. B.; Jannik, G. T.; Marra, J. C.; Oskolkov, B. Ya.; Bondarkov, M. D.; Gaschak, S. P.; Maksymenko, A. M.; Maksymenko, V. M.; Martynenko, V. I.

    2009-11-09

    Decommissioning of nuclear power plants and other nuclear fuel cycle facilities has been an imperative issue lately. There exist significant experience and generally accepted recommendations on remediation of lands with residual radioactive contamination; however, there are hardly any such recommendations on remediation of cooling ponds that, in most cases, are fairly large water reservoirs. The literature only describes remediation of minor reservoirs containing radioactive silt (a complete closure followed by preservation) or small water reservoirs resulting in reestablishing natural water flows. Problems associated with remediation of river reservoirs resulting in flooding of vast agricultural areas also have been described. In addition, the severity of environmental and economic problems related to the remedial activities is shown to exceed any potential benefits of these activities. One of the large, highly contaminated water reservoirs that require either remediation or closure is Karachay Lake near the MAYAK Production Association in the Chelyabinsk Region of Russia where liquid radioactive waste had been deep well injected for a long period of time. Backfilling of Karachay Lake is currently in progress. It should be noted that secondary environmental problems associated with its closure are considered to be of less importance since sustaining Karachay Lake would have presented a much higher radiological risk. Another well-known highly contaminated water reservoir is the Chernobyl Nuclear Power Plant (ChNPP) Cooling Pond, decommissioning of which is planned for the near future. This study summarizes the environmental problems associated with the ChNPP Cooling Pond decommissioning.

  6. Nuclear reactor kinetics and plant control

    CERN Document Server

    Oka, Yoshiaki

    2013-01-01

    Understanding time-dependent behaviors of nuclear reactors and the methods of their control is essential to the operation and safety of nuclear power plants. This book provides graduate students, researchers, and engineers in nuclear engineering comprehensive information on both the fundamental theory of nuclear reactor kinetics and control and the state-of-the-art practice in actual plants, as well as the idea of how to bridge the two. The first part focuses on understanding fundamental nuclear kinetics. It introduces delayed neutrons, fission chain reactions, point kinetics theory, reactivit

  7. Proliferation resistance features in nuclear reactor designs

    International Nuclear Information System (INIS)

    The paper presents a review of the main principles for technologies and materials protection from unauthorized proliferation and application to be considered in nuclear reactors designing. Nuclear power features certain operations sensitive to nuclear weapons proliferation (such as separation of uranium isotopes (enrichment), long storage of spent fuel, processing of spent fuel, plutonium and/or uranium recovery from spent fuel, storage of recovered fissile materials). Proliferation resistance is defined as a nuclear energy system characteristic that impedes the diversion or undeclared production of nuclear material, or misuse of technology with the purpose of acquiring nuclear weapons or other nuclear explosive devices. The basic principles of non-proliferation established in the INPRO international project sponsored by IAEA have been discussed as implemented for designing of the innovative nuclear energy systems based on fast lead-cooled nuclear reactors

  8. Autonomous Control of Space Nuclear Reactors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Nuclear reactors to support future lunar and Mars robotic and manned missions impose new and innovative technological requirements for their control and protection...

  9. MODERATOR ELEMENTS FOR UNIFORM POWER NUCLEAR REACTOR

    Science.gov (United States)

    Balent, R.

    1963-03-12

    This patent describes a method of obtaining a flatter flux and more uniform power generation across the core of a nuclear reactor. The method comprises using moderator elements having differing moderating strength. The elements have an increasing amount of the better moderating material as a function of radial and/or axial distance from the reactor core center. (AEC)

  10. Nuclear data requirements for fusion reactor shielding

    International Nuclear Information System (INIS)

    The nuclear data requirements for experimental, demonstration and commercial fusion reactors are reviewed. Particular emphasis is given to the shield as well as major reactor components of concern to the nuclear performance. The nuclear data requirements are defined as a result of analyzing four key areas. These are the most likely candidate materials, energy range, types of needed nuclear data, and the required accuracy in the data. Deducing the latter from the target goals for the accuracy in prediction is also discussed. A specific proposal of measurements is recommended. Priorities for acquisition of data are also assigned. (author)

  11. Large Scale Weather Control Using Nuclear Reactors

    CERN Document Server

    Singh-Modgil, M

    2002-01-01

    It is pointed out that controlled release of thermal energy from fission type nuclear reactors can be used to alter weather patterns over significantly large geographical regions. (1) Nuclear heat creates a low pressure region, which can be used to draw moist air from oceans, onto deserts. (2) Creation of low pressure zones over oceans using Nuclear heat can lead to Controlled Cyclone Creation (CCC).(3) Nuclear heat can also be used to melt glaciers and control water flow in rivers.

  12. Materials for generation-IV nuclear reactors

    International Nuclear Information System (INIS)

    Materials science and materials development are key issues for the implementation of innovative reactor systems such as those defined in the framework of the Generation IV. Six systems have been selected for Generation IV consideration: gas-cooled fast reactor, lead-cooled fast reactor, molten salt-cooled reactor, sodium-cooled fast reactor, supercritical water-cooled reactor, and very high temperature reactor. The structural materials need to resist much higher temperatures, higher neutron doses and extremely corrosive environment, which are beyond the experience of the current nuclear power plants. For this reason, the first consideration in the development of Generation-IV concepts is selection and deployment of materials that operate successfully in the aggressive operating environments expected in the Gen-IV concepts. This paper summarizes the Gen-IV operating environments and describes the various candidate materials under consideration for use in different structural applications. (author)

  13. Nuclear reactor vessel fuel thermal insulating barrier

    Science.gov (United States)

    Keegan, C. Patrick; Scobel, James H.; Wright, Richard F.

    2013-03-19

    The reactor vessel of a nuclear reactor installation which is suspended from the cold leg nozzles in a reactor cavity is provided with a lower thermal insulating barrier spaced from the reactor vessel that has a hemispherical lower section that increases in volume from the center line of the reactor to the outer extent of the diameter of the thermal insulating barrier and smoothly transitions up the side walls of the vessel. The space between the thermal insulating harrier and the reactor vessel forms a chamber which can be flooded with cooling water through passive valving to directly cool the reactor vessel in the event of a severe accident. The passive inlet valve for the cooling water includes a buoyant door that is normally maintained sealed under its own weight and floats open when the cavity is Hooded. Passively opening steam vents are also provided.

  14. Research nuclear reactor RA - Annual Report 1989

    International Nuclear Information System (INIS)

    Annual report concerning the project 'RA research nuclear reactor' for 1989, financed by the Serbian ministry of science is divided into two parts. First part is concerned with RA reactor operation and maintenance, which is the task of the Division for reactor engineering of the Institute for multidisciplinary studies and RA reactor engineering. Second part deals with radiation protection activities at the RA reactor which is the responsibility of the Institute for radiation protection. Scientific council of the Institute for multidisciplinary studies and RA reactor engineering has stated that this report describes adequately the activity and tasks fulfilled at the RA reactor in 1989. The scope and the quality of the work done were considered successful both concerning the maintenance and reconstruction, as well as radiation protection activities

  15. Thermal-hydraulic analysis of nuclear reactors

    CERN Document Server

    Zohuri, Bahman

    2015-01-01

    This text covers the fundamentals of thermodynamics required to understand electrical power generation systems and the application of these principles to nuclear reactor power plant systems. It is not a traditional general thermodynamics text, per se, but a practical thermodynamics volume intended to explain the fundamentals and apply them to the challenges facing actual nuclear power plants systems, where thermal hydraulics comes to play.  Written in a lucid, straight-forward style while retaining scientific rigor, the content is accessible to upper division undergraduate students and aimed at practicing engineers in nuclear power facilities and engineering scientists and technicians in industry, academic research groups, and national laboratories. The book is also a valuable resource for students and faculty in various engineering programs concerned with nuclear reactors. This book also: Provides extensive coverage of thermal hydraulics with thermodynamics in nuclear reactors, beginning with fundamental ...

  16. Teratological evaluation of pregnancy outcomes in Hungary after the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    The monthly distribution of pregnancy outcomes such as induced abortions, spontaneous abortions, stillbirths, newborns with birth weight under 2500 g, isolated congenital anomalies, identified multiple congenital anomaly syndromes including fetal radiation syndrome, and unidentified multiple congenital anomalies was evaluated in Hungary after the Chernobyl accident until Apr 1987. Only a somewhat higher rate of newborns with birth weight under 2500 g in May and June, 1986 was detected. It may have been due to premature labour caused by anxiety. (author) 15 refs.; 2 tabs

  17. The risks of nuclear energy technology. Safety concepts of light water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Raskob, Wolfgang; Landman, Claudia; Paesler-Sauer, Juergen [Karlsruher Institut fuer Technologie (KIT), Eggenstein-Leopoldshafen (Germany). Inst. fuer Kern- und Energietechnk (IKET); Kessler, Guenter; Veser, Anke; Schlueter, Franz-Hermann

    2014-11-01

    Analyses the risks of nuclear power stations. Discusses the security concept of reactors. Analyzes possible crash of air planes on a reactor containment. Presents measures against the spread of radioactivity after a severe accident. Written in engaging style for professionals and policy makers. The book analyses the risks of nuclear power stations. The security concept of reactors is explained. Measures against the spread of radioactivity after a severe accident, accidents of core melting and a possible crash of an air plane on a reactor containment are discussed. The book covers three scientific subjects of the safety concepts of Light Water Reactors: - A first part describes the basic safety design concepts of operating German Pressurized Water Reactors and Boiling Water Reactors including accident management measures introduced after the reactor accidents of Three Mile Island and Chernobyl. These safety concepts are also compared with the experiences of the Fukushima accidents. In addition, the safety design concepts of the future modern European Pressurized Water Reactor (EPR) and of the future modern Boiling Water Reactor SWR-1000 (KERENA) are presented. These are based on new safety research results of the past decades. - In a second, part the possible crash of military or heavy commercial air planes on a reactor containment is analyzed. It is shown that reactor containments can be designed to resist to such an airplane crash. - In a third part, an online decision system is presented. It allows to analyze the distribution of radioactivity in the atmosphere and to the environment after a severe reactor accident. It provides data for decisions to be taken by authorities for the minimization of radiobiological effects to the population. This book appeals to readers who have an interest in save living conditions and some understanding for physics or engineering.

  18. The risks of nuclear energy technology. Safety concepts of light water reactors

    International Nuclear Information System (INIS)

    Analyses the risks of nuclear power stations. Discusses the security concept of reactors. Analyzes possible crash of air planes on a reactor containment. Presents measures against the spread of radioactivity after a severe accident. Written in engaging style for professionals and policy makers. The book analyses the risks of nuclear power stations. The security concept of reactors is explained. Measures against the spread of radioactivity after a severe accident, accidents of core melting and a possible crash of an air plane on a reactor containment are discussed. The book covers three scientific subjects of the safety concepts of Light Water Reactors: - A first part describes the basic safety design concepts of operating German Pressurized Water Reactors and Boiling Water Reactors including accident management measures introduced after the reactor accidents of Three Mile Island and Chernobyl. These safety concepts are also compared with the experiences of the Fukushima accidents. In addition, the safety design concepts of the future modern European Pressurized Water Reactor (EPR) and of the future modern Boiling Water Reactor SWR-1000 (KERENA) are presented. These are based on new safety research results of the past decades. - In a second, part the possible crash of military or heavy commercial air planes on a reactor containment is analyzed. It is shown that reactor containments can be designed to resist to such an airplane crash. - In a third part, an online decision system is presented. It allows to analyze the distribution of radioactivity in the atmosphere and to the environment after a severe reactor accident. It provides data for decisions to be taken by authorities for the minimization of radiobiological effects to the population. This book appeals to readers who have an interest in save living conditions and some understanding for physics or engineering.

  19. Follow-up studies on genome damage in children after Chernobyl nuclear power plant accident.

    Science.gov (United States)

    Fucic, Aleksandra; Aghajanyan, Anna; Druzhinin, Vladimir; Minina, Varvara; Neronova, Elizaveta

    2016-09-01

    As children are more susceptible to ionizing radiation than adults, each nuclear accident demands special attention and care of this vulnerable population. The Chernobyl nuclear disaster occurred in a region populated with a large number of children, but despite all efforts and expertise of nuclear specialists, it was not possible to avoid casualties. As vast regions of Ukraine, Belarus and Russia were exposed to doses of ionizing radiation, which are known to be related with different diseases, shortly after the accident medical surveillance was launched, which also included analysis of genome damage. Child population affected by internal and external radiation consisted of subjects exposed prenatally, postnatally (both evacuated and non-evacuated), born by irradiated fathers who worked as liquidators, and parents exposed environmentally. In all groups of children during the last 30 years who were exposed to doses which were significantly higher than that recommended for general population of 1 mSv per year, increased genome damage was detected. Increased genome damage includes statistically higher frequency of dicentric and ring chromosomes, chromated and chromosome breaks, acentric fragments, translocations, and micronuclei. The presence of rogue cells confirmed internal contamination. Genome instability and radiosensitivity in children was detected both in evacuated and continuously exposed children. Today the population exposed to ionizing radiation in 1986 is in reproductive period of life and follow-up of this population and their offspring is of great importance. This review aims to give insight in results of studies, which reported genome damage in children in journals without language restrictions.

  20. Reactivity control assembly for nuclear reactor. [LMFBR

    Science.gov (United States)

    Bollinger, L.R.

    1982-03-17

    This invention, which resulted from a contact with the United States Department of Energy, relates to a control mechanism for a nuclear reactor and, more particularly, to an assembly for selectively shifting different numbers of reactivity modifying rods into and out of the core of a nuclear reactor. It has been proposed heretofore to control the reactivity of a breeder reactor by varying the depth of insertion of control rods (e.g., rods containing a fertile material such as ThO/sub 2/) in the core of the reactor, thereby varying the amount of neutron-thermalizing coolant and the amount of neutron-capturing material in the core. This invention relates to a mechanism which can advantageously be used in this type of reactor control system.

  1. Chernobyl: 30 years after - Proceedings of the technical meeting of the French Society of Radiation Protection

    International Nuclear Information System (INIS)

    The French Society of Radiation Protection (SFRP) organized a technical meeting on the present day situation of the Chernobyl site, 30 years after the accident of the nuclear power plant. The review deals with the situation of the facility and of its safety works, the environment, the management of wastes, the workers and populations exposure, and the health monitoring of the exposed populations. This document brings together the abstracts and the presentations (slides) of the different talks given at the meeting: 1 - The main highlights 30 years after the Chernobyl accident (Didier CHAMPION, SFRP); 2 - Circumstances, progress and consequences of the Chernobyl accident - Lessons and experience feedback for the other RBMK reactors (Michel CHOUHA, IRSN); 3 - Chernobyl, a confinement arch for 100 years (Patrick CHABRIER, Thomas CHAUVEAU - BOUYGUES); 4 - The reactor wastes management and the dismantling operations (Guy DAMETTE - IRSN); 5 - Environment contamination in the vicinity of the site (Yves THIRY - ANDRA); 6 - Impact of the accident on agriculture (Vanessa DURAND - IRSN); 7 - The fate of remediation wastes (Francois BESNUS - IRSN); 8 - Chernobyl fallouts in France (Philippe RENAUD - IRSN); 9 - The ecological consequences of the Chernobyl accident (Christelle ADAM-GUILLERMIN - IRSN); 10 - Results of liquidators and populations exposure (Florence MENETRIER - CEA); 11 - Thyroid cancers monitoring in the Chernobyl area and the role of modifying genetic factors (Fabienne LESUEUR - Institut Curie); 12 - Results of the Chernobyl accident health impact studies (Dominique LAURIER - IRSN); 13 - Impact on populations living condition (Thierry SCHNEIDER - CEPN); 14 - Molecular signature of radiation induced thyroid tumors (Sylvie CHEVILLARD - CEA)

  2. Chernobyl, 13 years after; Tchernobyl, 13 ans apres

    Energy Technology Data Exchange (ETDEWEB)

    Regniault-Lacharme, Mireille; Metivier, Henri [Inst. de Protection et de Surete Nucleaire, CEA Centre d' Etudes de Fontenay-aux-Roses, 92 (France)

    1999-04-01

    This is an annual report, regularly issued by IPSN, that presents the ecological and health consequences of the Chernobyl Nuclear Accident. The present status of the Chernobyl Nuclear Plant, which Ukraine engaged to stop definitively in year 2000, is summarized. The only reactor unit now in operation is Chernobylsk-3 Reactor which poses two safety questions: evolution of cracks in part of the tubing and behaviour of the pressure tubes. Although, some improvements in the RBMK reactor types were introduced, problems remain that make IPSN to stress the requirement of stopping this NPP completely. In the contaminated territories surrounding Chernobyl incidence rate of infant thyroid cancers continues to grow, reaching values 10 to 100 times higher than the natural rate. In France the IPSN analyzed 60,000 records carried out in 17 sites during May 1986 and April 1989. It was estimated that the individual dose received during 60 years (1986-2046) by the inhabitants of the most affected zone (eastern France) is lower than 1.5 mSv, a value lower than 1% of the natural cosmic and telluric radioactivity exposure for the same period. For the persons assumed to live in the most attacked forests (from eastern France) and nourishing daily with venison and mushrooms the highest estimate is 1 mSv a year. Concerning the 'hot spots', identified in mountains by IPSN and CRIIRAD, the doses received by excursionists are around 0.015 mSv. For an average inhabitant of the country the dose piled up in the thyroid due to iodine-131 fallout is estimated to 0.5-2 mSv for an adult and 6.5-16 mSv for an infant. These doses are 100 to 1000 times lower than the ones to which the infants living in the neighbourhood of Chernobyl are exposed to. The contents of the report is displayed in the following six chapters: 1. Chernobyl in some figures; 2. The 'sarcophagus' and the reactors of the Chernobyl NPP; 3. Health consequences of the Chernobyl accident;. 4. The impact of

  3. Short lived radionuclides in food and feed after the nuclear accident in Chernobyl

    International Nuclear Information System (INIS)

    The results of identification and short lived radionuclides (I-131, I(Te)-132, Cs-136, Ce-141, 144, Ru-103, 106, Ba(La)-140, Zr-95, Mo-99, Nb-95, Sb-125) mass activities evaluation in food (milk and dairies, meat, honey, fruits, vegetables) and feeds (oilseed rupe, alfalfa, fresh green mass) after the nuclear accident at Chernobyl, in 1986, are presented. The results indicate that in the first month after the accident and afterwards, in the first half of the year, the contribution of the short lived radionuclides in the total activity of the samples ranged from 2-64%, varying with food and feed, locality and time of sampling. Compared to the activity of I-131, the short lived radionuclides contributed from 1.3 to 470%, while compared to the activities of the long term radionuclides Cs-134 and Cs-137, the activity of the short lived radionuclides in the first half of the year after the accident ranged from 12% to more than 300%. The traces of Ag-110m were found in the majority of the samples, too. (1 tab.)

  4. Chernobyl operators: criminals or victims?

    Science.gov (United States)

    Munipov, V M

    1992-10-01

    The blame for the 1986 Chernobyl disaster has been variously attributed to the operating personnel, the plant management, the design of the reactor, and the lack of adequate safety information in the Soviet nuclear industry. This paper considers a number of design faults, operational shortcomings and human errors that combined in the accident. It examines the sequence of events leading up to the accident, design problems in the reactor and cooling rods, and the course of the accident itself. It considers the ergonomics aspects, and expresses the view that the main cause of the accident was inadequate human-machine interaction. Finally, it stresses the continuing inadequacies of the Soviet nuclear system, and emphasizes that unless the ergonomics lessons are fully learned, a similar disaster could still occur.

  5. Nuclear Power from Fission Reactors. An Introduction.

    Science.gov (United States)

    Department of Energy, Washington, DC. Technical Information Center.

    The purpose of this booklet is to provide a basic understanding of nuclear fission energy and different fission reaction concepts. Topics discussed are: energy use and production, current uses of fuels, oil and gas consumption, alternative energy sources, fossil fuel plants, nuclear plants, boiling water and pressurized water reactors, the light…

  6. U.S. Nuclear Power Reactor Plant Status

    Data.gov (United States)

    Nuclear Regulatory Commission — Demographic data on U.S. commercial nuclear power reactors, including: plant name/unit number, docket number, location, licensee, reactor/containment type, nuclear...

  7. Workshop on short-term health effects of reactor accidents: Chernobyl

    International Nuclear Information System (INIS)

    The high-dose early-effects research that has been continued has been done in the context of infrequent accidents with large radiation sources and the use of bone marrow transfusions for treating malignancies, especially leukemia. It thus seemed appropriate to bring together those who have done research on and have had experience with massive whole-body radiation. The objectives were to review what is known about the acute effects of whole-body irradiation, to review the current knowledge of therapy, and particularly of the diagnostic and immunologic problems encountered in bone marrow therapy, and to compare this knowledge with observations made to date on the Chernobyl accident radiation casualties. Dr. Robert Gale, who had helped to care for these casualties, was present at the Workshop. It was hoped that such a review would help those making continuing clinical and pathological observations on the Chernobyl casualties, and that these observations would provide a basis for recommendations for additional research that might result in improved ability to manage successfully this type of severe injury

  8. Workshop on short-term health effects of reactor accidents: Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    1986-08-08

    The high-dose early-effects research that has been continued has been done in the context of infrequent accidents with large radiation sources and the use of bone marrow transfusions for treating malignancies, especially leukemia. It thus seemed appropriate to bring together those who have done research on and have had experience with massive whole-body radiation. The objectives were to review what is known about the acute effects of whole-body irradiation, to review the current knowledge of therapy, and particularly of the diagnostic and immunologic problems encountered in bone marrow therapy, and to compare this knowledge with observations made to date on the Chernobyl accident radiation casualties. Dr. Robert Gale, who had helped to care for these casualties, was present at the Workshop. It was hoped that such a review would help those making continuing clinical and pathological observations on the Chernobyl casualties, and that these observations would provide a basis for recommendations for additional research that might result in improved ability to manage successfully this type of severe injury.

  9. Inhalation of radionuclides during agricultural work in areas contaminated as a result of the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    Radionuclide concentrations have been determined inside and outside the cabs of tractors operated on soils that are typical of the 30 km exclusion zone around the Chernobyl nuclear power plant. It was found that when the total plutonium deposit exceeded 3.7 kBq m-2 and the 137Cs deposit exceeded 7.4 MBq m-2, the levels of these radionuclides in the operator's cabin could exceed the maximum permissible air concentrations. However, due to the seasonal nature of work, the quantities of these radionuclides inhaled would not exceed the annual limit on intake. Dose to the lungs caused by the inhalation of hot particles has been addressed by either including or neglecting spatial dose distribution. The levels of risk of carcinogenic changes in cells of lung tissue calculated according to each of the two approaches have been shown to be of the same order of magnitude. (author)

  10. Safety review, assessment and inspection on research reactors, experimental reactors, nuclear heating reactors and critical facilities

    International Nuclear Information System (INIS)

    In 1998, the NNSA organized to complete the nuclear safety review on the test loop in-reactor operation of the High-flux Engineering Experimental Reactor (HFEER) and the re-operation of the China Pulsed Reactor and the Uranium-water Criticality Facility. The NNSA conducted the nuclear safety review on the CP application of the China Experimental Fast Reactor (CEFR) and the siting of China Advanced Research Reactor (CARR), and carried out the construction supervision on HTR-10, and dealt with the event about the technological tube breakage of HWRR and other events

  11. Cold nuclear fusion reactor and nuclear fusion rocket

    OpenAIRE

    Huang Zhenqiang

    2013-01-01

    "Nuclear restraint inertial guidance directly hit the cold nuclear fusion reactor and ion speed dc transformer" [1], referred to as "cold fusion reactor" invention patents, Chinese Patent Application No. CN: 200910129632.7 [2]. The invention is characterized in that: at room temperature under vacuum conditions, specific combinations of the installation space of the electromagnetic field, based on light nuclei intrinsic magnetic moment and the electric field, the first two strings of the nucle...

  12. News on the natural nuclear reactor

    International Nuclear Information System (INIS)

    Data characterizing conditions of occurrence and the status of a natural nuclear reactor the remnants of which are discovered in the ore open pit of the Oklo deposit (Gabon) are presented. Transport of alkali earth elements (Rb, Sr, Cs and Ba) as well as Pd, Ag, Cd and Te isotopes near the reactor was investigated. Reactor criticality arose, probably, during or soon after U deposition. The reactor has ceased after 500000 years of operation; the energy of about 15 GW x year was generated. Approximately 80 t of uranium (12 tons of sup(235)U) were utilized during reactor operation. Approximately 10 tons of fission products and 4 tons of sup(239)Pu were formed. Reactor operation was periodical, multiply repeated. Water migrating over sandstone pores was not only a moderator but a self-regulator as well

  13. Chernobyl nuclear accident hydrologic analysis and emergency evaluation of radionuclide distributions in the Dnieper River, Ukraine, during the 1993 summer flood

    Energy Technology Data Exchange (ETDEWEB)

    Voitsekhovitch, O.V. [Ukrainian Hydrometeorological Inst., Kiev (Ukraine); Zheleznyak, M.J. [Ukrainian Academy of Sciences, Kiev (Ukraine). Cybernetics Center; Onishi, Y. [Pacific Northwest Lab., Richland, WA (United States)

    1994-06-01

    This report describes joint activities of Program 7.1.F, ``Radionuclide Transport in Water and Soil Systems,`` of the USA/Commonwealth of Independent States (CIS) Joint Coordinating Committee of Civilian Nuclear Reactor Safety to study the hydrogeochemical behavior of radionuclides released to the Pripyat and Dnieper rivers from the Chernobyl Nuclear Power Plant in Ukraine. These joint activities included rapid evaluation of radionuclide distributions in the Pripyat and Dnieper river system and field data evaluation and modeling for the 1993 summer flood to assist the Ukrainian government in their emergency response during the flood. In July-August 1993, heavy rainfall over the Pripyat River Catchment in Belarus and Ukraine caused severe flooding, significantly raising {sup 90}Sr concentrations in the river. Near the Chernobyl area, the maximum {sup 90}Sr concentration in the Pripyat River reached 20--25 PCi/L in early August; near the Pripyat River mouth, the concentration rose to 35 pCi/L. The peak {sup 90}Sr concentration in the Kiev Reservoir (a major source of drinking water for Kiev) was 12 pCi/L. Based on these measured radionuclide levels, additional modeling results and the assumption of water purification in a water treatment station, {sup 90}Sr concentrations in Kiev`s drinking water were estimated to be less than 8 pCi/L. Unlike {sup 90}Sr, {sup 137}Cs concentrations in the Pripyat River during the flood did not rise significantly to the pre-flood levels. Estimated {sup 137}Cs concentrations for the Kiev drinking water were two orders of magnitude lower than the drinking water standard of 500 pCi/L for {sup 137}Cs.

  14. Chernobyl nuclear accident hydrologic analysis and emergency evaluation of radionuclide distributions in the Dnieper River, Ukraine, during the 1993 summer flood

    International Nuclear Information System (INIS)

    This report describes joint activities of Program 7.1.F, ''Radionuclide Transport in Water and Soil Systems,'' of the USA/Commonwealth of Independent States (CIS) Joint Coordinating Committee of Civilian Nuclear Reactor Safety to study the hydrogeochemical behavior of radionuclides released to the Pripyat and Dnieper rivers from the Chernobyl Nuclear Power Plant in Ukraine. These joint activities included rapid evaluation of radionuclide distributions in the Pripyat and Dnieper river system and field data evaluation and modeling for the 1993 summer flood to assist the Ukrainian government in their emergency response during the flood. In July-August 1993, heavy rainfall over the Pripyat River Catchment in Belarus and Ukraine caused severe flooding, significantly raising 90Sr concentrations in the river. Near the Chernobyl area, the maximum 90Sr concentration in the Pripyat River reached 20--25 PCi/L in early August; near the Pripyat River mouth, the concentration rose to 35 pCi/L. The peak 90Sr concentration in the Kiev Reservoir (a major source of drinking water for Kiev) was 12 pCi/L. Based on these measured radionuclide levels, additional modeling results and the assumption of water purification in a water treatment station, 90Sr concentrations in Kiev's drinking water were estimated to be less than 8 pCi/L. Unlike 90Sr, 137Cs concentrations in the Pripyat River during the flood did not rise significantly to the pre-flood levels. Estimated 137Cs concentrations for the Kiev drinking water were two orders of magnitude lower than the drinking water standard of 500 pCi/L for 137Cs

  15. Features of a subcritical nuclear reactor

    International Nuclear Information System (INIS)

    Highlights: • The keff was calculated using six factor formula and MCNP code. • Both methods agree when the reactor is loaded from 800 to 1900 kg. • With the MCNP5 code the neutron spectra and doses were estimated. • The Ambient dose was measured outside the subcritical assembly. - Abstract: A subcritical nuclear reactor is a device where the nuclear-fission chain reaction is initiated and maintained using an external neutron source. It is a valuable educational and research tool where in a safe way many reactor parameters can be measured. Here, we have used the six-factor formula to calculate the effective multiplication factor of a subcritical nuclear reactor Nuclear Chicago model 9000. Using the MCNP5 code, a three-dimensional model of the subcritical reactor was developed to estimate the effective multiplication factor, the neutron spectra, and the total and thermal neutron fluences along the radial and axial axis. The MCNP5 results of the effective multiplication factor were compared with those obtained from the six-factor formula. The effective dose and the Ambient dose equivalent, at three sites outside the reactor, were estimated; the Ambient dose equivalent was also measured and compared with the calculated values

  16. MOLTEN FLUORIDE NUCLEAR REACTOR FUEL

    Science.gov (United States)

    Barton, C.J.; Grimes, W.R.

    1960-01-01

    Molten-salt reactor fuel compositions consisting of mixtures of fluoride salts are reported. In its broadest form, the composition contains an alkali fluoride such as sodium fluoride, zirconium tetrafluoride, and a uranium fluoride, the latter being the tetrafluoride or trifluoride or a mixture of the two. An outstanding property of these fuel compositions is a high coeffieient of thermal expansion which provides a negative temperature coefficient of reactivity in reactors in which they are used.

  17. Thermionic reactors for space nuclear power

    Science.gov (United States)

    Griaznov, Georgii M.; Zhabotinskii, Evgenii E.; Serbin, Victor I.; Zrodnikov, Anatolii V.; Pupko, Victor Ia.; Ponomarev-Stepnoi, Nikolai N.; Usov, V. A.; Nikolaev, Iu. V.

    Compact thermionic nuclear reactor systems with satisfactory mass performance are competitive with space nuclear power systems based on the organic Rankine and closed Brayton cycles. The mass characteristics of the thermionic space nuclear power system are better than that of the solar power system for power levels beyond about 10 kWe. Longlife thermionic fuel element requirements, including their optimal dimensions, and common requirements for the in-core thermionic reactor design are formulated. Thermal and fast in-core thermionic reactors are considered and the ranges of their sensible use are discussed. Some design features of the fast in-core thermionic reactors cores (power range to 1 MWe) including a choice of coolants are discussed. Mass and dimensional performance for thermionic nuclear power reactor system are assessed. It is concluded that thermionic space nuclear power systems are promising power supplies for spacecrafts and that a single basic type of thermionic fuel element may be used for power requirements ranging to several hundred kWe.

  18. Optimally moderated nuclear fission reactor and fuel source therefor

    Science.gov (United States)

    Ougouag, Abderrafi M.; Terry, William K.; Gougar, Hans D.

    2008-07-22

    An improved nuclear fission reactor of the continuous fueling type involves determining an asymptotic equilibrium state for the nuclear fission reactor and providing the reactor with a moderator-to-fuel ratio that is optimally moderated for the asymptotic equilibrium state of the nuclear fission reactor; the fuel-to-moderator ratio allowing the nuclear fission reactor to be substantially continuously operated in an optimally moderated state.

  19. Introduction to the neutron kinetics of nuclear power reactors

    CERN Document Server

    Tyror, J G; Grant, P J

    2013-01-01

    An Introduction to the Neutron Kinetics of Nuclear Power Reactors introduces the reader to the neutron kinetics of nuclear power reactors. Topics covered include the neutron physics of reactor kinetics, feedback effects, water-moderated reactors, fast reactors, and methods of plant control. The reactor transients following faults are also discussed, along with the use of computers in the study of power reactor kinetics. This book is comprised of eight chapters and begins with an overview of the reactor physics characteristics of a nuclear power reactor and their influence on system design and

  20. Technical characteristics of new generation of nuclear power plants; Charakterystyka techniczna elektrowni jadrowych nowej generacji

    Energy Technology Data Exchange (ETDEWEB)

    Janczak, R.; Mikulski, A.; Staron, E. [Instytut Energii Atomowej, Swierk-Otwock (Poland)

    1997-12-31

    The concept of Advanced Light Water Reactors (ALWR) as a new generation of nuclear reactors for energetics have been presented. The influence of reactor accidents (TMI and Chernobyl) on technical and scientific development of nuclear reactors has been discussed from the view point of safety assurance and requirements being defined by American and European Nuclear Regulatory commission. 12 refs, 14 figs.

  1. Water shielding nuclear reactor container

    International Nuclear Information System (INIS)

    The reactor container of the present invention contains a reactor pressure vessel, and has double steel plate walls endurable to elevated inner pressure and keeping airtightness, and shielding water is filled inside from a water injection port. It is endurable to a great inner pressure satisfactorily and keep airtightness by the two spaced relatively thin steel plates. It exhibits radiation shielding effect by filling water substantially the same as that of a conventional reactor container made of iron reinforced concretes. Then, it is no more necessary to use concretes for the construction of the reactor container, which shortens the term of the construction, and saves the construction cost. In addition, a cooling effect for the reactor container is provided. Syphons are disposed contiguously to a water injection port and the top end of the syphon is immersed in an equipment temporarily storage pool, and further, pipelines are connected to the double steel plate walls or the syphons for supplying shielding water to enhance the cooling effect. (N.H.)

  2. The safety of Ontario's nuclear reactors

    International Nuclear Information System (INIS)

    A Select Committee of the Legislature of Ontario was established to examine the affairs of Ontario Hydro, the provincial electrical utility. Extensive public hearings were held on several topics including the safety of nuclear power reactors operating in Ontario. The Committee found that these reactors are acceptably safe. Many of the 24 recommendations in this report deal with the licensing process and public access to information. (O.T.)

  3. Nuclear Research Center IRT reactor dynamics calculation

    International Nuclear Information System (INIS)

    The main features of the code DIRT, for dynamical calculations are described in the paper. With the results obtained by the program, an analysis of the dynamic behaviour of the Research Reactor IRT of the Nuclear Research Center (CIN) is performed. Different transitories were considered such as variation of the system reactivity, coolant inlet temperature variation and also variations of the coolant velocity through the reactor core. 3 refs

  4. Advanced nuclear reactor types and technologies

    Energy Technology Data Exchange (ETDEWEB)

    Ignatiev, V. [ed.; Feinberg, O.; Morozov, A. [Russian Research Centre `Kurchatov Institute`, Moscow (Russian Federation); Devell, L. [Studsvik Eco and Safety AB, Nykoeping (Sweden)

    1995-07-01

    The document is a comprehensive world-wide catalogue of concepts and designs of advanced fission reactor types and fuel cycle technologies. Two parts have been prepared: Part 1 Reactors for Power Production and Part 2 Heating and Other Reactor Applications. Part 3, which will cover advanced waste management technology, reprocessing and disposal for different nuclear fission options is planned for compilation during 1995. The catalogue was prepared according to a special format which briefly presents the project title, technical approach, development status, application of the technology, reactor type, power output, and organization which developed these designs. Part 1 and 2 cover water cooled reactors, liquid metal fast reactors, gas-cooled reactors and molten salt reactors. Subcritical accelerator-driven systems are also considered. Various reactor applications as power production, heat generation, ship propulsion, space power sources and transmutation of such waste are included. Each project is described within a few pages with the main features of an actual design using a table with main technical data and figure as well as references for additional information. Each chapter starts with an introduction which briefly describes main trends and approaches in this field. Explanations of terms and abbreviations are provided in a glossary.

  5. Advanced nuclear reactor types and technologies

    International Nuclear Information System (INIS)

    The document is a comprehensive world-wide catalogue of concepts and designs of advanced fission reactor types and fuel cycle technologies. Two parts have been prepared: Part 1 Reactors for Power Production and Part 2 Heating and Other Reactor Applications. Part 3, which will cover advanced waste management technology, reprocessing and disposal for different nuclear fission options is planned for compilation during 1995. The catalogue was prepared according to a special format which briefly presents the project title, technical approach, development status, application of the technology, reactor type, power output, and organization which developed these designs. Part 1 and 2 cover water cooled reactors, liquid metal fast reactors, gas-cooled reactors and molten salt reactors. Subcritical accelerator-driven systems are also considered. Various reactor applications as power production, heat generation, ship propulsion, space power sources and transmutation of such waste are included. Each project is described within a few pages with the main features of an actual design using a table with main technical data and figure as well as references for additional information. Each chapter starts with an introduction which briefly describes main trends and approaches in this field. Explanations of terms and abbreviations are provided in a glossary

  6. Chernobyl, 14 years later; Tchernobyl, 14 ans apres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    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.

  7. Oklo reactors and implications for nuclear science

    CERN Document Server

    Davis, E D; Sharapov, E I

    2014-01-01

    We summarize the nuclear physics interests in the Oklo natural nuclear reactors, focusing particularly on developments over the past two decades. Modeling of the reactors has become increasingly sophisticated, employing Monte Carlo simulations with realistic geometries and materials that can generate both the thermal and epithermal fractions. The water content and the temperatures of the reactors have been uncertain parameters. We discuss recent work pointing to lower temperatures than earlier assumed. Nuclear cross sections are input to all Oklo modeling and we discuss a parameter, the $^{175}$Lu ground state cross section for thermal neutron capture leading to the isomer $^{176\\mathrm{m}}$ Lu, that warrants further investigation. Studies of the time dependence of dimensionless fundamental constants have been a driver for much of the recent work on Oklo. We critically review neutron resonance energy shifts and their dependence on the fine structure constant $\\alpha$ and the ratio $X_q=m_q/\\Lambda$ (where $m_...

  8. 78 FR 64028 - Decommissioning of Nuclear Power Reactors

    Science.gov (United States)

    2013-10-25

    ... COMMISSION Decommissioning of Nuclear Power Reactors AGENCY: Nuclear Regulatory Commission. ACTION... regulatory guide (RG) 1.184 ``Decommissioning of Nuclear Power Reactors.'' This guide describes a method NRC... decommissioning process for nuclear power reactors. The revision takes advantage of the 13 years...

  9. Evolution of nuclear reactor containments in India: Addressing the present day challenges

    International Nuclear Information System (INIS)

    Indigenously developed Pressurized Heavy Water Reactors (PHWRs) that form the backbone of current stage of nuclear power development in India have seen continuous evolution of their containment systems. This evolution that has taken place over implementation of 18 PHWRs (200/220/540 MWe) has encompassed all aspects of containment design, viz. the structural system, energy management system, radio-activity management and hydrogen management system. As a part of ongoing efforts toward strengthening of safety performance, India is also ready with the design of Advance Heavy Water Reactor (AHWR), which represents a technology demonstrator for advanced reactor systems and for thorium utilization. This reactor has a number of improved passive safety features and it is capable of meeting the demanding safety challenges that future reactor system would be expected to meet as a result of emerging expectations in the background of accidents over the past three decades viz. those at Three Mile Island (1979), Chernobyl (1986) and most recently at Fukushima (2011). In this lecture I shall focus on the evolution of nuclear reactor containments in India and highlight the design, associated structural and thermal hydraulics safety assessment made over the years for the improvement of containment performance

  10. Nuclear reactor fuel element splitter

    International Nuclear Information System (INIS)

    A method and apparatus are disclosed for removing nuclear fuel from a clad fuel element. The fuel element is power driven past laser beams which simultaneously cut the cladding lengthwise into at least two longitudinal pieces. The axially cut lengths of cladding are then separated, causing the nuclear fuel contained therein to drop into a receptacle for later disposition. The cut lengths of cladding comprise nuclear waste which is disposed of in a suitable manner. 6 claims, 10 drawing figures

  11. Nuclear reactors with auxiliary boiler circuit

    International Nuclear Information System (INIS)

    A gas-cooled nuclear reactor has a main circulatory system for the gaseous coolant incorporating one or more main energy converting units, such as gas turbines, and an auxiliary circulatory system for the gaseous coolant incorporating at least one steam generating boiler arranged to be heated by the coolant after its passage through the reactor core to provide steam for driving an auxiliary steam turbine, such an arrangement providing a simplified start-up procedure also providing emergency duties associated with long term heat removal on reactor shut down

  12. Local AREA networks in advanced nuclear reactors

    International Nuclear Information System (INIS)

    The report assesses Local Area Network Communications with a view to their application in advanced nuclear reactor control and protection systems. Attention is focussed on commercially available techniques and systems for achieving the high reliability and availability required. A basis for evaluating network characteristics in terms of broadband or baseband type, medium, topology, node structure and access method is established. The reliability and availability of networks is then discussed. Several commercial networks are briefly assessed and a distinction made between general purpose networks and those suitable for process control. The communications requirements of nuclear reactor control and protection systems are compared with the facilities provided by current technology

  13. Ten years after the Chernobyl accident: reporting on nuclear and other hazards in six Swedish newspapers

    International Nuclear Information System (INIS)

    A European Commission sponsored study (RISKPERCOM) involving France, Norway, Spain, Sweden, and the UK, is concerned with surveying public perceptions of radiation related and other risks. This was partly done by distributing a questionnaire in each country at three different times in 1996: before, during and after the expected media attention given to the tenth anniversary of the Chernobyl accident. A selection of print media were analyzed, during a period of eight weeks - four weeks before the anniversary, and four weeks after - making it possible to contrast any changes between the three waves of the questionnaire with the results of the media study. The present report aims at providing a picture of the Swedish media coverage of different kinds of risks during the period referred to above. The purpose of the analysis is thus primarily of a descriptive nature; explanatory factors are only considered in an ad hoc manner while discussing the results and their possible implications. Naturally, the findings arising from this study cannot alone serve as a basis for making statements about the effects of risk related content on the Swedish newspaper readers. The risk stories included in the analysis were those dealing with one or more of the twenty different hazard items referred to in several of the questions in the RISKPERCOM questionnaire. Radiation and nuclear power energy were not the only issues of concern. The selection covered a wide range of other hazards as well, in order to provide for a wide risk panorama, thus making it possible to compare specific risk qualities etc., as these were presented in the media

  14. Ten years after the Chernobyl accident: reporting on nuclear and other hazards in six Swedish newspapers

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Aasa; Sjoeberg, L.; Waahlberg, A. af

    1997-07-01

    A European Commission sponsored study (RISKPERCOM) involving France, Norway, Spain, Sweden, and the UK, is concerned with surveying public perceptions of radiation related and other risks. This was partly done by distributing a questionnaire in each country at three different times in 1996: before, during and after the expected media attention given to the tenth anniversary of the Chernobyl accident. A selection of print media were analyzed, during a period of eight weeks - four weeks before the anniversary, and four weeks after - making it possible to contrast any changes between the three waves of the questionnaire with the results of the media study. The present report aims at providing a picture of the Swedish media coverage of different kinds of risks during the period referred to above. The purpose of the analysis is thus primarily of a descriptive nature; explanatory factors are only considered in an ad hoc manner while discussing the results and their possible implications. Naturally, the findings arising from this study cannot alone serve as a basis for making statements about the effects of risk related content on the Swedish newspaper readers. The risk stories included in the analysis were those dealing with one or more of the twenty different hazard items referred to in several of the questions in the RISKPERCOM questionnaire. Radiation and nuclear power energy were not the only issues of concern. The selection covered a wide range of other hazards as well, in order to provide for a wide risk panorama, thus making it possible to compare specific risk qualities etc., as these were presented in the media 70 refs, 40 refs

  15. Methods in nuclear reactors calculations

    International Nuclear Information System (INIS)

    Studies are made of the neutron transport equation corresponding to the the real and virtual reactors, as well as the starting hypotheses. Methods are developed to solve the transport equation in slab geometry, and Pl; Bl; Ml; Sn and discrete ordinates approximations. (Author)

  16. Nuclear safety. Concerns about the nuclear power reactors in Cuba

    International Nuclear Information System (INIS)

    In 1976, the Soviet Union and Cuba concluded an agreement to construct two 440-megawatt nuclear power reactors near Cienfuegos on the south central coast of Cuba, about 180 miles south of Key West, Florida. The construction of these reactors, which began around 1983, was a high priority for Cuba because of its heavy dependence on imported oil. Cuba is estimated to need an electrical generation capacity of 3,000 megawatts by the end of the decade. When completed, the first reactor unit would provide a significant percentage (estimated at over 15 percent) of Cuba's need for electricity. It is uncertain when Cuba's nuclear power reactors will become operational. On September 5, 1992, Fidel Castro announced the suspension of construction at both of Cuba's reactors because Cuba could not meet the financial terms set by the Russian government to complete the reactors. Cuban officials had initially planned to start up the first of the two nuclear reactors by the end of 1993. However, before the September 5 announcement, it was estimated that this reactor would not be operational until late 1995 or early 1996. The civil construction (such as floors and walls) of the first reactor is currently estimated to be about 90 percent to 97 percent complete, but only about 37 percent of the reactor equipment (such as pipes, pumps, and motors) has been installed. The civil construction of the second reactor is about 20 percent to 30 percent complete. No information was available about the status of equipment for the second reactor. According to former Cuban nuclear power and electrical engineers and a technician, all of whom worked at the reactor site and have recently emigrated from Cuba, Cuba's nuclear power program suffers from poor construction practices and inadequate training for future reactor operators. One former official has alleged, for example, that the first reactor containment structure, which is designed to prevent the accidental release of radioactive material into

  17. Advanced nuclear reactor systems - an Indian perspective

    International Nuclear Information System (INIS)

    The Indian nuclear power programme envisages use of closed nuclear fuel cycle and thorium utilisation as its mainstay for its sustainable growth. The current levels of deployment of nuclear energy in India need to be multiplied nearly hundred fold to reach levels of electricity generation that would facilitate the country to achieve energy independence as well as a developed status. The Indian thorium based nuclear energy systems are being developed to achieve sustainability in respect of fuel resource along with enhanced safety and reduced waste generation. Advanced Heavy Water Reactor and its variants have been designed to meet these objectives. The Indian High Temperature Reactor programme also envisages use of thorium-based fuel with advanced levels of passive safety features. (author)

  18. Nuclear data for fusion reactor technology

    International Nuclear Information System (INIS)

    The meeting was organized in four sessions and four working groups devoted to the following topics: Requirements of nuclear data for fusion reactor technology (6 papers); Status of experimental and theoretical investigations of microscopic nuclear data (10 papers); Status of existing libraries for fusion neutronic calculations (5 papers); and Status of integral experiments and benchmark tests (6 papers). A separate abstract was prepared for each of these papers

  19. Reference Neutron Radiographs of Nuclear Reactor Fuel

    OpenAIRE

    Domanus, Joseph Czeslaw

    1986-01-01

    Reference neutron radiographs of nuclear reactor fuel were produced by the Euraton Neutron Radiography Working Group and published in 1984 by the Reidel Publishing Company. In this collection a classification is given of the various neutron radiographic findings, that can occur in different parts of pelletized, annular and vibro-conpacted nuclear fuel pins. Those parts of the pins are shown where changes of appearance differ from those for the parts as fabricated. Also radiographs of those as...

  20. Nuclear reactor alignment plate configuration

    Science.gov (United States)

    Altman, David A; Forsyth, David R; Smith, Richard E; Singleton, Norman R

    2014-01-28

    An alignment plate that is attached to a core barrel of a pressurized water reactor and fits within slots within a top plate of a lower core shroud and upper core plate to maintain lateral alignment of the reactor internals. The alignment plate is connected to the core barrel through two vertically-spaced dowel pins that extend from the outside surface of the core barrel through a reinforcement pad and into corresponding holes in the alignment plate. Additionally, threaded fasteners are inserted around the perimeter of the reinforcement pad and into the alignment plate to further secure the alignment plate to the core barrel. A fillet weld also is deposited around the perimeter of the reinforcement pad. To accomodate thermal growth between the alignment plate and the core barrel, a gap is left above, below and at both sides of one of the dowel pins in the alignment plate holes through with the dowel pins pass.

  1. Neutronics of nuclear power reactors

    International Nuclear Information System (INIS)

    This review, prepared on the occasion of 25th ETAN Conference describes the research activities in the field of neutronics which started in 1947. A number of researchers in Yugoslav Institutes was engaged in development of neutronics theory and calculation methods related to power reactors since 1960. To illustrate the activities of Yugoslav authors, this review contains the list of the most important relevant papers published in international journals

  2. Nuclear Data and the Oklo Natural Nuclear Reactors

    Science.gov (United States)

    Gould, C. R.; Sharapov, E. I.; Sonzogni, A. A.

    2014-04-01

    Data from the Oklo natural nuclear reactors have enabled some of the most sensitive terrestrial tests of time variation of dimensionless fundamental constants. The constraints on variation of αEM, the fine structure constant are particular good, but depend on the reliability of the nuclear data, and on the reliability of the modeling of the reactor environment. We briefly review the history of these tests and discuss our recent work in 1) attempting to better bound the temperatures at which the reactors operated, 2) investigating whether the γ-ray fluxes in the reactors could have contributed to changing lutetium isotopic abundances and 3) determining whether lanthanum isotopic data could provide an alternate estimate of the neutron fluence.

  3. Decommissioning a nuclear reactor. [Water Boiler Reactor Project

    Energy Technology Data Exchange (ETDEWEB)

    Montoya, G.M.

    1991-01-01

    The process of decommissioning a facility such as a nuclear reactor or reprocessing plant presents many waste management options and concerns. Waste minimization is a primary consideration, along with protecting a personnel and the environment. Waste management is complicated in that both radioactive and chemical hazardous wastes must be dealt with. This paper presents the general decommissioning approach of a recent project at Los Alamos. Included are the following technical objectives: site characterization work that provided a thorough physical, chemical, and radiological assessment of the contamination at the site; demonstration of the safe and cost-effective dismantlement of a highly contaminated and activated nuclear-fuelded reactor; and techniques used in minimizing radioactive and hazardous waste. 12 figs.

  4. Technological Transfer from Research Nuclear Reactors to New Generation Nuclear Power Reactors

    Science.gov (United States)

    Radulescu, Laura; Pavelescu, Margarit

    2010-01-01

    The goal of this paper is the analysis of the technological transfer role in the nuclear field, with particular emphasis on nuclear reactors domain. The presentation is sustained by historical arguments. In this frame, it is very important to start with the achievements of the first nuclear systems, for instant those with natural uranium as fuel and heavy water as moderator, following in time through the history until the New Generation Nuclear Power Reactors. Starting with 1940, the accelerated development of the industry has implied the increase of the global demand for energy. In this respect, the nuclear energy could play an important role, being essentially an unlimited source of energy. However, the nuclear option faces the challenges of increasingly demanding safety requirements, economic competitiveness and public acceptance. Worldwide, a significant amount of experience has been accumulated during development, licensing, construction, and operation of nuclear power reactors. The experience gained is a strong basis for further improvements. Actually, the nuclear programs of many countries are addressing the development of advanced reactors, which are intended to have better economics, higher reliability, improved safety, and proliferation-resistant characteristics in order to overcome the current concerns about nuclear power. Advanced reactors, now under development, may help to meet the demand for energy power of both developed and developing countries as well as for district heating, desalination and for process heat. The paper gives historical examples that illustrate the steps pursued from first research nuclear reactors to present advanced power reactors. Emphasis was laid upon the fact that the progress is due to the great discoveries of the nuclear scientists using the technological transfer.

  5. International cooperation on technical support for regulation of safety-related activities on the transformation of the destroyed Chernobyl Nuclear Power Plant Power Unit into an ecologically safe system

    International Nuclear Information System (INIS)

    The world's most severe nuclear accident destroyed the fourth unit at the Chernobyl nuclear power plant in 1986. In the six months following the accident, a localizing building was erected over the unit to contain the nuclear materials and provide support services for managing the destroyed reactor. Since 1997, an international project which includes both urgent measures for stabilization and safety upgrading as well as long-term measures for transforming the facility into an ecologically safe system has been under way. This paper discusses an important aspect of this project which has been the cooperation amongst the technical support organizations of the Ukrainian regulatory authorities and the technical support from international organizations. (author)

  6. Nuclear reactors - the inevitable energy option

    International Nuclear Information System (INIS)

    The demand for energy in India is sure to rise year after year. Every possible energy source needs to be utilized to its fullest potential to bridge the gap between the demand and supply of electricity. Even while deciding the energy option, the availability of natural resources for future generation and effect of environment for the energy option chosen are to be taken care of. Out of the non conventional sources of electricity, nuclear electricity has greatest potential. Robust and safe energy option has to be harnessed to its potential. We have to bring down the cost of electricity. Even among nuclear reactors, electricity through Fast Breeder Reactors has greater potential. The Prototype Fast Breeder Reactor is a trend setter for moving into an era of electricity generation in the country. The paper brings details of the safety features, accomplishments of the technical challenges and the efforts on hand to reduce the unit energy cost by Nuclear Reactors. The paper also touches upon advantages, environmental impact of Fast Breeder Reactors for this abundant energy resources. Paper will also give a glimpse on technological challenges in design, construction and the preservation. (author)

  7. Power Nuclear Reactors: technology and innovation for development in future

    International Nuclear Information System (INIS)

    The conference is about some historicals task of the fission technology as well as many types of Nuclear Reactors. Enrichment of fuel, wastes, research reactors and power reactors, a brief advertisment about Uruguay electric siystem and power generation, energetic worldwide, proliferation, safety reactors, incidents, accidents, Three-Mile Island accident, Chernobil accident, damages, risks, classification and description of Power reactors steam generation, nuclear reactor cooling systems, future view

  8. The siting of UK nuclear reactors

    International Nuclear Information System (INIS)

    Choosing a suitable site for a nuclear power station requires the consideration and balancing of several factors. Some ‘physical’ site characteristics, such as the local climate and the potential for seismic activity, will be generic to all reactors designs, while others, such as the availability of cooling water, the area of land required and geological conditions capable of sustaining the weight of the reactor and other buildings will to an extent be dependent on the particular design of reactor chosen (or alternatively the reactor design chosen may to an extent be dependent on the characteristics of an available site). However, one particularly interesting tension is a human and demographic one. On the one hand it is beneficial to place nuclear stations close to centres of population, to reduce transmission losses and other costs (including to the local environment) of transporting electricity over large distances from generator to consumer. On the other it is advantageous to place nuclear stations some distance away from such population centres in order to minimise the potential human consequences of a major release of radioactive materials in the (extremely unlikely) event of a major nuclear accident, not only in terms of direct exposure but also concerning the management of emergency planning, notably evacuation. This paper considers the emergence of policies aimed at managing this tension in the UK. In the first phase of nuclear development (roughly speaking 1945–1965) there was a highly cautious attitude, with installations being placed in remote rural locations with very low population density. The second phase (1965–1985) saw a more relaxed approach, allowing the development of AGR nuclear power stations (which with concrete pressure vessels were regarded as significantly safer) closer to population centres (in ‘semi-urban’ locations, notably at Hartlepool and Heysham). In the third phase (1985–2005) there was very little new nuclear

  9. The siting of UK nuclear reactors.

    Science.gov (United States)

    Grimston, Malcolm; Nuttall, William J; Vaughan, Geoff

    2014-06-01

    Choosing a suitable site for a nuclear power station requires the consideration and balancing of several factors. Some 'physical' site characteristics, such as the local climate and the potential for seismic activity, will be generic to all reactors designs, while others, such as the availability of cooling water, the area of land required and geological conditions capable of sustaining the weight of the reactor and other buildings will to an extent be dependent on the particular design of reactor chosen (or alternatively the reactor design chosen may to an extent be dependent on the characteristics of an available site). However, one particularly interesting tension is a human and demographic one. On the one hand it is beneficial to place nuclear stations close to centres of population, to reduce transmission losses and other costs (including to the local environment) of transporting electricity over large distances from generator to consumer. On the other it is advantageous to place nuclear stations some distance away from such population centres in order to minimise the potential human consequences of a major release of radioactive materials in the (extremely unlikely) event of a major nuclear accident, not only in terms of direct exposure but also concerning the management of emergency planning, notably evacuation.This paper considers the emergence of policies aimed at managing this tension in the UK. In the first phase of nuclear development (roughly speaking 1945-1965) there was a highly cautious attitude, with installations being placed in remote rural locations with very low population density. The second phase (1965-1985) saw a more relaxed approach, allowing the development of AGR nuclear power stations (which with concrete pressure vessels were regarded as significantly safer) closer to population centres (in 'semi-urban' locations, notably at Hartlepool and Heysham). In the third phase (1985-2005) there was very little new nuclear development, Sizewell

  10. Current Abstracts Nuclear Reactors and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Bales, J.D.; Hicks, S.C. [eds.

    1993-01-01

    This publication Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency`s Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on the Energy Science and Technology Database and Nuclear Science Abstracts (NSA) database. Current information, added daily to the Energy Science and Technology Database, is available to DOE and its contractors through the DOE Integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user`s needs.

  11. Refueling machine for a nuclear reactor

    International Nuclear Information System (INIS)

    An improved refuelling machine for inserting and removing fuel assemblies from a nuclear reactor is described which has been designed to increase the reliability of such machines. The system incorporates features which enable the refuelling operation to be performed more efficiently and economically. (U.K.)

  12. Ultrasonic flaw detection device in nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sakurai, Yoshishige; Takabayashi, Jun-ichi

    1996-02-02

    Flaws on an outer circumferential surface of a shroud at inner side than jet pumps in a nuclear reactor are simply and reliably detected using ultrasonic waves. Ultrasonic waves are irradiated to the shroud which surrounds a reactor core at the inner side and has a plurality of jet pumps at the outer side at predetermined distances. An ultrasonic wave probe which detects flaws based on reflecting waves is suspended using a suspending rope. A jet nozzle is attached to a probe-attaching portion and water is jetted out to reactor water to move the probe-attaching portion in the reactor. Then, flaws can be detected easily and reliably using ultrasonic waves even at a narrow gap at the inner side of each jet pump. (N.H.).

  13. Ultrasonic flaw detection device in nuclear reactor

    International Nuclear Information System (INIS)

    Flaws on an outer circumferential surface of a shroud at inner side than jet pumps in a nuclear reactor are simply and reliably detected using ultrasonic waves. Ultrasonic waves are irradiated to the shroud which surrounds a reactor core at the inner side and has a plurality of jet pumps at the outer side at predetermined distances. An ultrasonic wave probe which detects flaws based on reflecting waves is suspended using a suspending rope. A jet nozzle is attached to a probe-attaching portion and water is jetted out to reactor water to move the probe-attaching portion in the reactor. Then, flaws can be detected easily and reliably using ultrasonic waves even at a narrow gap at the inner side of each jet pump. (N.H.)

  14. Safety review, assessment and inspection on research reactors, experimental reactors, nuclear heating reactors and critical facilities

    International Nuclear Information System (INIS)

    The NNSA organized mainly in 1999 to complete the verification loop in core of the high flux experimental reactor with the 2000 kW fuel elements, the re-starting of China Pulsed Reactor, review and assessment on nuclear safety for the restarting of the Uranium-water critical Facility and treat the fracture event with the fuel tubes in the HWRR

  15. Safety review, assessment and inspection on research reactors, experimental reactors and nuclear heating reactors

    International Nuclear Information System (INIS)

    The NNSA and its regional office step further strengthened the regulation on the safety of in-service research reactors in 1996. A lot of work has been done on the supervision of safe in rectifying the review and assessment of modified items, the review of operational documents, the treatment of accidents, the establishment of the system for operational experience feedback, daily and routine inspection on nuclear safety. The internal management of the operating organization on nuclear safety was further strengthened, nuclear safety culture was further enhanced, the promotion in nuclear safety and the safety situation for in-service research reactors were improved

  16. Use of nuclear reactors for seawater desalination

    International Nuclear Information System (INIS)

    The last International Atomic Energy Agency (IAEA) status report on desalination, including nuclear desalination, was issued nearly 2 decades ago. The impending water crisis in many parts of the world, and especially in the Middle East, makes it appropriate to provide an updated report as a basis for consideration of future activities. This report provides a state-of-the-art review of desalination and pertinent nuclear reactor technology. Information is included on fresh water needs and costs, environmental risks associated with alternatives for water production, and data regarding the technical and economic characteristics of immediately available desalination systems, as well as compatible nuclear technology. 68 refs, 60 figs, 11 tabs

  17. Medical and biological aspects of the Chernobyl nuclear accident influence on the population of the Republic of Moldova

    International Nuclear Information System (INIS)

    Complete text of publication follows. Stress factors action on the population health evaluation, especially on the emergency workers remains one of the most important problems of the contemporary medicine. In this line the Chernobyl nuclear accident (CNA) that took place on the 26th April 1986 at the Chernobyl nuclear power station (NPS) is an eloquent example. Radioactive substances produced in the result of CNA fell out in a significant part of the Europe, including the Republic of Moldova territory, affecting more than 5,000,000 persons. In CNA consequences liquidation participated a lot of military staff including a great number of reservists. Lack of previous experience in the field (it was the first large-scale nuclear accident) made it impossible to prepare specially trained personnel for CNA limitation and liquidation. Consequently a lot of military staff even from the first days presented to medical authorities with a gamma of symptoms, which were henceforth characterized as somatic diseases after detailed investigations. Ionizing radiation influence on the health status of the participants in diminishing of consequences of the Chernobyl nuclear accident (PDCCNA) evaluation is difficult enough and so calls for an ample multilateral study applying modern diagnostic techniques. Large studies were yet conducted in the Russian Federation, the Ukraine and the Republic of Belarus. Acquired data suggests the existence of noticeable deteriorating effect of ionizing radiation produced secondary to CNA with the increased incidence of health status disturbances in affected population. Approximately 3500 inhabitants from the Republic of Moldova took part in the Chernobyl nuclear accident consequences liquidation. Study objective comprises the determination of clinical, immunological and cytogenetic features in PDCCNA from the Republic of Moldova and their descendants. Between 1996 and 2005 period 850 patients - participants in removal of consequences of Chernobyl

  18. Medical and biological aspects of the Chernobyl nuclear accident influence on the population of the Republic of Moldova

    International Nuclear Information System (INIS)

    Complete test of publication follows. Stress factors action on the population health evaluation, especially on the emergency workers remains on e of the most important problems of the contemporary medicine. In this line the Chernobyl nuclear accident (CNA) that look place on the 26th April 1986 at the Chernobyl Nuclear Power Station (CNPS) is an eloquent example. Radioactive substances produced in the result of CNA fell out in a significant part of the Europe, including the Republic of Moldova territory, affecting more than 5,000,000 persons. In CNA consequences liquidation participated a lot of military staff including a great number of reservists. Lack of previous experience in the field (it was the first large-scale nuclear accident) made it impossible to prepare specially trained personnel for CNA limitation and liquidation. Consequently a lot of military staff even from the first days presented to medical authorities with a gamma of symptoms, which were henceforth characterized as somatic diseases after detailed investigations. Ionizing radiation influence on the health status of the participants in diminishing of consequences of the Chernobyl nuclear accident (PDCCNA) evaluation is difficult enough and so calls for an ample multilateral study applying modern diagnostic techniques. Large studies were yet conducted in the Russian Federation, the Ukraine and the Republic of Belarus. Acquired data suggests the existence of noticeable deteriorating effect of ionizing radiation produced secondary to CNA with the increased incidence of health status disturbances in affected population. Approximately 3500 inhabitants from the Republic of Moldova took part in the Chernobyl nuclear accident consequences liquidation. Study objective comprises the determination of clinical, immunological and cytogenetic features in PDCCNA from the Republic of Moldova and their descendants. Between 1996 and 2005 period 850 patients - participants in removal of consequences of Chernobyl

  19. Five Lectures on Nuclear Reactors Presented at Cal Tech

    Science.gov (United States)

    Weinberg, Alvin M.

    1956-02-10

    The basic issues involved in the physics and engineering of nuclear reactors are summarized. Topics discussed include theory of reactor design, technical problems in power reactors, physical problems in nuclear power production, and future developments in nuclear power. (C.H.)

  20. Chernobyl disaster

    Energy Technology Data Exchange (ETDEWEB)

    Haynes, V.; Bojcun, M.

    1988-01-01

    The Chernobyl disaster is examined in chronological order from the experiment that led to the explosions, to the firefighting efforts, the release of radioactivity, its fallout, the evacuations from the contaminated zone and the long-term medical, ecological, economic and political repercussions. The sources of information are nearly all Soviet - the Ukranian and Russian press, Moscow and Kiev radio broadcasts, Soviet television documentaries and the report of the Soviet government commission to the International Atomic Energy Agency in August 1986. Reports by the United Kingdom Atomic Energy Authority, the Central Electricity Generating Board and the International Atomic Energy Agency have also been used. The latter chapters look at who was to blame for the accident, what impact the accident has had on Soviet society and why the Soviet government continues to expand its nuclear power programme.

  1. Radiation Exposure and Thyroid Cancer Risk After the Fukushima Nuclear Power Plant Accident in Comparison with the Chernobyl Accident.

    Science.gov (United States)

    Yamashita, S; Takamura, N; Ohtsuru, A; Suzuki, S

    2016-09-01

    The actual implementation of the epidemiological study on human health risk from low dose and low-dose rate radiation exposure and the comprehensive long-term radiation health effects survey are important especially after radiological and nuclear accidents because of public fear and concern about the long-term health effects of low-dose radiation exposure have increased considerably. Since the Great East Japan earthquake and the Fukushima Daiichi Nuclear Power Plant accident in Japan, Fukushima Prefecture has started the Fukushima Health Management Survey Project for the purpose of long-term health care administration and medical early diagnosis/treatment for the prefectural residents. Especially on a basis of the lessons learned from the Chernobyl accident, both thyroid examination and mental health care are critically important irrespective of the level of radiation exposure. There are considerable differences between Chernobyl and Fukushima regarding radiation dose to the public, and it is very difficult to estimate retrospectively internal exposure dose from the short-lived radioactive iodines. Therefore, the necessity of thyroid ultrasound examination in Fukushima and the intermediate results of this survey targeting children will be reviewed and discussed in order to avoid any misunderstanding or misinterpretation of the high detection rate of childhood thyroid cancer.

  2. Simulation of a marine nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kusunoki, Tsuyoshi; Kyouya, Masahiko; Kobayashi, Hideo; Ochiai, Masaaki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Office of Nuclear Ship Research and Development

    1995-02-01

    A Nuclear-powered ship Engineering Simulation SYstem (NESSY) has been developed by the Japan Atomic Energy Research Institute as an advanced design tool for research and development of future marine reactors. A marine reactor must respond to changing loads and to the ship`s motions because of the ship`s maneuvering and its presence in a marine environment. The NESSY has combined programs for the reactor plant behavior calculations and the ship`s motion calculations. Thus, it can simulate reactor power fluctuations caused by changing loads and the ship`s motions. It can also simulate the behavior of water in the pressurizer and steam generators. This water sloshes in response to the ship`s motions. The performance of NESSY has been verified by comparing the simulation calculations with the measured data obtained by experiments performed using the nuclear ship Mutsu. The effects of changing loads and the ship`s motions on the reactor behavior can be accurately simulated by NESSY.

  3. INFLUENCE OF ANTIHYPERTENSIVE THERAPY ON PSYCHOLOGICAL STATUS OF CHERNOBYL NUCLEAR POWER PLANT ACCIDENT CONSEQUENCES LIQUIDATORS

    Directory of Open Access Journals (Sweden)

    E. M. Manoshkina

    2006-01-01

    Full Text Available Aim. To study psychological status and influence of antihypertensive therapy (AHT on it in Chernobyl nuclear power plant (NPP accident consequences liquidators, who suffer arterial hyper-tension (AH, with controlled treatment compared to the standard treatment in out-patient clinic. Material and methods. 81 liquidators with AH (all men were included into open compara-tive randomized study. Study duration was 12 months. Patients were randomized into main group (MG and control group (CG. Patients of MG received strictly regulated stepped AHT based on ACE inhibitor spirapril 6 mg daily (Quadropril®, Pliva-AVD, hypothiazide was added if necessary (12.5-25 mg daily and afterwards – atenolol (12.5-100 mg daily. In CG AHT and its correction was set by physician in polyclinic. Brief multifactor questionnaire for personality analysis was used to study psychological status. Results. 57 patients completed the study, 28 in MG and 29 in CG. In MG target blood pres-sure (BP levels were reached in 22 (78.6% patients, in CG – in 11 (38% patients (p<0.01. The main feature of psychological status of liquidators with AH was hypochondriac, depressive and anxious disorders. Controlled AHT made it possible to reach improvement in psychological status, i.e. growth of optimism and activity of patients, more often, than standard treatment in out-patient clinics. Increase in number of patients with pronounced anxious changes was observed in CG. Effi-ciency of AHT in liquidators with AH is connected with severity of depressive disturbances: in subgroups with inefficient treatment patients had the highest level of depression. In liquidators with AH, possessing neurotic disturbances, spirapril was efficient both as monotherapy, and in combina-tion with diuretic hydrochlorothiazide and beta-blocker atenolol. Conclusion. Controlled AHT in liquidators with AH has advantages over standard treatment in out-patient clinic and results in more frequent target BP level

  4. Method and apparatus for increasing fuel efficiency in nuclear reactors

    International Nuclear Information System (INIS)

    This patent describes an improved method of producing a spectral shift in a nuclear reactor to achieve increased nuclear fuel efficiency, the nuclear reactor containing a fluid moderator juxtaposed with fuel elements containing the nuclear fuel, which comprises disposing within the fluid moderator stationary non-poison displacer rods for achieving the spectral shift, the displacer rods exhibiting a continuous reduction in volume during operation of the nuclear reactor whereby the fluid moderator increases in volume as the nuclear fuel is burned in the nuclear reactor

  5. Cold nuclear fusion reactor and nuclear fusion rocket

    Directory of Open Access Journals (Sweden)

    Huang Zhenqiang

    2013-10-01

    Full Text Available "Nuclear restraint inertial guidance directly hit the cold nuclear fusion reactor and ion speed dc transformer" [1], referred to as "cold fusion reactor" invention patents, Chinese Patent Application No. CN: 200910129632.7 [2]. The invention is characterized in that: at room temperature under vacuum conditions, specific combinations of the installation space of the electromagnetic field, based on light nuclei intrinsic magnetic moment and the electric field, the first two strings of the nuclei to be bound fusion on the same line (track of. Re-use nuclear spin angular momentum vector inherent nearly the speed of light to form a super strong spin rotation gyro inertial guidance features, to overcome the Coulomb repulsion strong bias barrier to achieve fusion directly hit. Similar constraints apply nuclear inertial guidance mode for different speeds and energy ion beam mixing speed, the design of ion speed dc transformer is cold fusion reactors, nuclear fusion engines and such nuclear power plants and power delivery systems start important supporting equipment, so apply for a patent merger

  6. Distributed computing and nuclear reactor analysis

    International Nuclear Information System (INIS)

    Large-scale scientific and engineering calculations for nuclear reactor analysis can now be carried out effectively in a distributed computing environment, at costs far lower than for traditional mainframes. The distributed computing environment must include support for traditional system services, such as a queuing system for batch work, reliable filesystem backups, and parallel processing capabilities for large jobs. All ANL computer codes for reactor analysis have been adapted successfully to a distributed system based on workstations and X-terminals. Distributed parallel processing has been demonstrated to be effective for long-running Monte Carlo calculations

  7. Medical Radioisotopes Production Without A Nuclear Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Van der Keur, H.

    2010-05-15

    This report is answering the key question: Is it possible to ban the use of research reactors for the production of medical radioisotopes? Chapter 2 offers a summarized overview on the history of nuclear medicine. Chapter 3 gives an overview of the basic principles and understandings of nuclear medicine. The production of radioisotopes and its use in radiopharmaceuticals as a tracer for imaging particular parts of the inside of the human body (diagnosis) or as an agent in radiotherapy. Chapter 4 lists the use of popular medical radioisotopes used in nuclear imaging techniques and radiotherapy. Chapter 5 analyses reactor-based radioisotopes that can be produced by particle accelerators on commercial scale, other alternatives and the advantages of the cyclotron. Chapter 6 gives an overview of recent developments and prospects in worldwide radioisotopes production. Chapter 7 presents discussion, conclusions and recommendations, and is answering the abovementioned key question of this report: Is it possible to ban the use of a nuclear reactor for the production of radiopharmaceuticals? Is a safe and secure production of radioisotopes possible?.

  8. Lubrication greases for nuclear reactors

    International Nuclear Information System (INIS)

    Lubricating greases are essential components of many machines used in nuclear power plants. Where these machines are subject to radiation the life of the grease will be reduced due to deterioration of the components of the grease. According to the chemical nature of the grease used a greater or lesser resistance to radiation will be observed. Tests and techniques to evaluate the performance of greases before and after irradiation are described. The results of these tests show that conventional premium greases will resist comparatively low levels of irradiation, whilst greases formulated from correctly selected components can tolerate quite high levels of radiation permitting the machines they lubricate to attain their designed service lives

  9. Seminar on Comparative assessment of the environmental impact of radionuclides released during three major nuclear accidents: Kyshtym, Windscale, Chernobyl. Vol. 1

    International Nuclear Information System (INIS)

    These proceedings of seminar on comparative assessment of the environmental impact of radionuclides released during three major nuclear accidents (Kyshtym, Windscale, Chernobyl) are divided into 5 parts bearing on: part 1: accident source terms; part 2: atmospheric dispersion, resuspension, chemical and physical forms of contamination; part 3: environmental contamination and transfer; part 4: radiological implications for man and his environment; part 5: countermeasures

  10. My Good, what have we done. From Hiroshima to Chernobyl - our way into nuclear disaster. Mein Gott, was haben wir getan. Von Hiroshima nach Tschernobyl - der Weg in das atomare Verhaengnis

    Energy Technology Data Exchange (ETDEWEB)

    Jaenecke, H.

    1987-01-01

    The atomic energy debate has become the life-and-death question of ouer times. But there is great uncertainty, and confusion is increasing. This book leads the reader back to the origin of the atomic age. It describes the progression from a scientific discovery, nuclear fission, to the dropping of the atom bomb - and from the bomb to the supposed blessing of 'peaceful' utilisation of atomic energy. But the bomb and the reactor pose the same threat. After Chernobyl, we know that the apocalypse can happen even without a war. The book is to be read as a narrative in which human personalities play the major roles: Madame Curie, who discovered radioactivity, Edward Teller, the inventor of the hydrogen bomb, the nameless engineers in the control rooms of nuclear power stations who now hold the fate of all of us in their hands. The Appendix contains an interview with Carl Friedrich von Weizsaecker.

  11. Nuclear energy center site survey reactor plant considerations

    Energy Technology Data Exchange (ETDEWEB)

    Harty, H.

    1976-05-01

    The Energy Reorganization Act of 1974 required the Nuclear Regulatory Commission (NRC) to make a nuclear energy center site survey (NECSS). Background information for the NECSS report was developed in a series of tasks which include: socioeconomic inpacts; environmental impact (reactor facilities); emergency response capability (reactor facilities); aging of nuclear energy centers; and dry cooled nuclear energy centers.

  12. Nuclear energy center site survey reactor plant considerations

    International Nuclear Information System (INIS)

    The Energy Reorganization Act of 1974 required the Nuclear Regulatory Commission (NRC) to make a nuclear energy center site survey (NECSS). Background information for the NECSS report was developed in a series of tasks which include: socioeconomic inpacts; environmental impact (reactor facilities); emergency response capability (reactor facilities); aging of nuclear energy centers; and dry cooled nuclear energy centers

  13. Dynamics of contents and organic forms of radionuclide compounds in the liquid phase of forest soils in the zone of contamination from the Chernobyl Nuclear Power Plant

    International Nuclear Information System (INIS)

    In the profile of forest soils in a 30-km zone around the Chernobyl nuclear power plant (NPP), in areas characterized by different positions in relation to the source of emission, the authors determined the relative contents of long-lived radionuclides 106Ru, 134,137Cs, and 144Ce in soil solutions (as of 1987). On the example of 137Cs, they consider the dynamics (1987-1990) of relative contents and forms in which the radionuclide is found in the liquid phase of soils in the zone of radioactive contamination from the Chernobyl NPP

  14. Quality assurance of ECCS in nuclear reactors

    International Nuclear Information System (INIS)

    Size and shape of split or rupture in clad increases the whole body radiation exposure to the staff of the nuclear reactors. Suggests that a plant operating with 0.125 percent pin-hole fuel cladding defects showed a general five-fold increase in whole-body radiation exposure rates in some areas of the plant when compared to a sister plant with high-integrity fuel. Therefore Quality Assurance (QA) checks on Emergency Core Cooling System (ECCS) in Nuclear Reactors are very important to ensure minimum radiation hazard during Loss of Coolant Accident (LOCA). These checks will protect environment and public from radiation to great extent. The rate of rise of fuel temperature subsequent to LOCA should be lower than 5.5℃/s

  15. Nuclear data requirements for fission reactor decommissioning

    International Nuclear Information System (INIS)

    The meeting was attended by 13 participants from 8 Member States and 2 International Organizations who reviewed the status of the nuclear data libraries and computer codes used to calculate the radioactive inventory in the reactor unit components for the decommissioning purposes. Nuclides and nuclear reactions important for determination of the radiation fields during decommissioning and for the final disposal of radioactive waste from the decommissioned units were identified. Accuracy requirements for the relevant nuclear data were considered. The present publication contains the text of the reports by the participants and their recommendations to the Nuclear Data Section of the IAEA. A separate abstract was prepared for each of these reports. Refs, figs and tabs

  16. Reference Neutron Radiographs of Nuclear Reactor Fuel

    DEFF Research Database (Denmark)

    Domanus, Joseph Czeslaw

    1986-01-01

    Reference neutron radiographs of nuclear reactor fuel were produced by the Euraton Neutron Radiography Working Group and published in 1984 by the Reidel Publishing Company. In this collection a classification is given of the various neutron radiographic findings, that can occur in different parts...... of pelletized, annular and vibro-conpacted nuclear fuel pins. Those parts of the pins are shown where changes of appearance differ from those for the parts as fabricated. Also radiographs of those as fabricated parts are included. The collection contains 158 neutron radiographs, reproduced on photographic paper...

  17. The regulatory challenges of decommissioning nuclear reactors

    International Nuclear Information System (INIS)

    Each nuclear power plant, fuel cycle facility and nuclear research and test facility that is operating today will eventually reach the end of its useful life and cease operation. During the period of its decommissioning, it is important to properly manage the health and environmental hazards and physical protection measures of the shutdown facility in order to protect the health and safety of the public and workers and to safeguard any nuclear materials. In this regard, the nuclear safety regulatory body is responsible for independently assuring that decommissioning activities are conducted safely, that radioactive materials and spent nuclear fuel are disposed of properly and that the site is in an acceptable end state. The purpose of this report is to describe the broad range of safety, environmental, organisational, human factors and public policy issues that may arise during the decommissioning of nuclear reactors and that the regulatory body should be prepared to deal with in the framework of its national regulatory system. The intended audience is primarily nuclear regulators, although the information and ideas may also be of interest to government authorities, environmental regulators, nuclear operating organisations, technical expert organisations and the general public. (author)

  18. [90Sr and 137Cs in higher aquatic plants of the Chernobyl nuclear plant exlusion zone

    Science.gov (United States)

    Gudkov, D I; Derevets, V V; Kuz'menko, M I; Nazarov, A B

    2001-01-01

    The content of radionuclides 90Sr and 137Cs in higher aquatic plants of water objects within Chernobyl NPP exclusion zone has been analysed. Biodiversity of phytocenose was studied and species-indicators of radioactive contamination were revealed. The seasonal dynamics of radionuclide content in macrophytes was studied and the role of main aquatic plant clumps in processes of 137Cs and 90Sr distribution in abiotic component of biohydrocenose was demonstrated.

  19. The spatial distribution of caesium-137 over Northern Ireland from fallout from the Chernobyl nuclear accident

    OpenAIRE

    Rawlins, B. G.; Scheib, C.; Tyler, A.N.; Jones, D.; Webster, R; Young, M. E.

    2009-01-01

    The spatial distribution of caesium-137 (137Cs) across the land is of much interest because it can tell us about the redistribution of the radionuclide as a result of soil erosion, differential migration through the soil—or its complement, differential retention in the soil. Any such inferences from survey measurements depend on the assumption of a broadly even distribution from weapons testing fallout, and the substantial deposition of 137Cs in rain following the Chernobyl accide...

  20. Contamination of the air and other environmental samples of the Ulm region by radioactive fission products after the accident of the Chernobyl reactor

    International Nuclear Information System (INIS)

    Since April 30, 1986, the radioactivity of the fission products released by the accident of the Chernobyl reactor has been measured in the air of the city of Ulm. The airborne dust samples were collected with flow calibrated samplers on cellulose acetate membrane filters and counted with a high resolution gamma ray spectrometer. Later on, the radioactivity measurements were expanded to other relevant environmental samples contaminated by radioactive atmospheric precipitates including grass, spruce needles, mosses, lichens, various kinds of food, drinking water, asphalt and concrete surface layers, municipal sewage sludge and sewage sludge ash. This paper reports the obtained results. (orig.)

  1. Some views on nuclear reactor safety

    International Nuclear Information System (INIS)

    This document is the text of a speech given by Pierre Y. Tanguy (Electricite de France) at the 22nd Water Reactor Safety Meeting held in Bethesda, MD in 1994. He describes the EDF nuclear program in broad terms and proceeds to discuss operational safety results with EDF plants. The speaker also outlines actions to enhance safety planned for the future, and he briefly mentions French cooperation with the Chinese on the Daya Bay project

  2. Shield structure for a nuclear reactor

    International Nuclear Information System (INIS)

    An improved nuclear reactor shield structure is described for use where there are significant amounts of fast neutron flux above an energy level of approximately 70 keV. The shield includes structural supports and neutron moderator and absorber systems. A portion at least of the neutron moderator material is magnesium oxide either alone or in combination with other moderator materials such as graphite and iron. (U.K.)

  3. Multivariable Feedback Control of Nuclear Reactors

    Directory of Open Access Journals (Sweden)

    Rune Moen

    1982-07-01

    Full Text Available Multivariable feedback control has been adapted for optimal control of the spatial power distribution in nuclear reactor cores. Two design techniques, based on the theory of automatic control, were developed: the State Variable Feedback (SVF is an application of the linear optimal control theory, and the Multivariable Frequency Response (MFR is based on a generalization of the traditional frequency response approach to control system design.

  4. Some views on nuclear reactor safety

    Energy Technology Data Exchange (ETDEWEB)

    Tanguy, P.Y. [Electricite de France, Paris (France)

    1995-04-01

    This document is the text of a speech given by Pierre Y. Tanguy (Electricite de France) at the 22nd Water Reactor Safety Meeting held in Bethesda, MD in 1994. He describes the EDF nuclear program in broad terms and proceeds to discuss operational safety results with EDF plants. The speaker also outlines actions to enhance safety planned for the future, and he briefly mentions French cooperation with the Chinese on the Daya Bay project.

  5. Radioactive contamination levels in China and health evaluation following radioactive release from Soviet Chernobyl Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    For the purpose of evaluating radiological effects in China and protecting population from possible consequences of Soviet Chernobyl nuclear power plant accident, the national network of environmental radioactive monitoring stations in China started emergency monitoring since May 1st, 1986. From May 1st to the end of July, 131I, 137Cs and other man-made radionuclides in some environmental media were found in large amounts. 131I was detected obviously in daily deposition, surface water, growing leafy vegetables, fresh milk and sheep thyroid samples. It is proved that radioactive fallout from Soviet Chernobyl accident has spreaded in atmosphere over the territory of China; so, the environment has been contaminated. Thyroid dose for individuals of general public in China was estimated. The effective dose equivalents for adults are lower than 2 μSv, for infants lower than 30 μSv; they are low as compared with 'Basic Health Standards for Radiological Protection' in China. The emergency sanitary protective measures were considered unnecessary

  6. Nuclear vapor thermal reactor propulsion technology

    Science.gov (United States)

    Maya, Isaac; Diaz, Nils J.; Dugan, Edward T.; Watanabe, Yoichi; McClanahan, James A.; Wen-Hsiung Tu, Carman, Robert L.

    1993-01-01

    The conceptual design of a nuclear rocket based on the vapor core reactor is presented. The Nuclear Vapor Thermal Rocket (NVTR) offers the potential for a specific impulse of 1000 to 1200 s at thrust-to-weight ratios of 1 to 2. The design is based on NERVA geometry and systems with the solid fuel replaced by uranium tetrafluoride (UF4) vapor. The closed-loop core does not rely on hydrodynamic confinement of the fuel. The hydrogen propellant is separated from the UF4 fuel gas by graphite structure. The hydrogen is maintained at high pressure (˜100 atm), and exits the core at 3,100 K to 3,500 K. Zirconium carbide and hafnium carbide coatings are used to protect the hot graphite from the hydrogen. The core is surrounded by beryllium oxide reflector. The nuclear reactor core has been integrated into a 75 klb engine design using an expander cycle and dual turbopumps. The NVTR offers the potential for an incremental technology development pathway to high performance gas core reactors. Since the fuel is readily available, it also offers advantages in the initial cost of development, as it will not require major expenditures for fuel development.

  7. Oklo reactors and implications for nuclear science

    Science.gov (United States)

    Davis, E. D.; Gould, C. R.; Sharapov, E. I.

    2014-04-01

    We summarize the nuclear physics interests in the Oklo natural nuclear reactors, focusing particularly on developments over the past two decades. Modeling of the reactors has become increasingly sophisticated, employing Monte Carlo simulations with realistic geometries and materials that can generate both the thermal and epithermal fractions. The water content and the temperatures of the reactors have been uncertain parameters. We discuss recent work pointing to lower temperatures than earlier assumed. Nuclear cross-sections are input to all Oklo modeling and we discuss a parameter, the 175Lu ground state cross-section for thermal neutron capture leading to the isomer 176mLu, that warrants further investigation. Studies of the time dependence of dimensionless fundamental constants have been a driver for much of the recent work on Oklo. We critically review neutron resonance energy shifts and their dependence on the fine structure constant α and the ratio Xq = mq/Λ (where mq is the average of the u and d current quark masses and Λ is the mass scale of quantum chromodynamics (QCD)). We suggest a formula for the combined sensitivity to α and Xq that exhibits the dependence on proton number Z and mass number A, potentially allowing quantum electrodynamic (QED) and QCD effects to be disentangled if a broader range of isotopic abundance data becomes available.

  8. Opening Address: Japan's Nuclear Reactor Strategy

    International Nuclear Information System (INIS)

    Thank you very much Mr. Chairman for your kind introduction. Distinguished colleagues, ladies and gentlemen, it is a great pleasure for me to have the chance to address you here in Kyoto at this 'International Conference on Fast Reactors and Related Fuel Cycles (FR09)'. At the outset, I would like to thank the IAEA for organizing this conference and, taking this opportunity, I would like to assure its new Director General, Y. Amano, of Japan's continuing support for the IAEA. I am looking forward to continuing to work with the IAEA in order to extend the benefits of the peaceful uses of nuclear energy and science and technology to a global population. We are witnessing today a global emergence of interest in the construction of nuclear power plants. There are a number of reasons for this. Major factors are the urgent and ever growing need for energy, particularly in the developing world, fluctuations in fossil fuel prices, the pursuit of security of energy supply and the growing recognition of the need to combat global warming. Despite the global economic crisis, the IAEA's latest projections continue to show a significant increase in nuclear generating capacity in the medium term. The low projection for 2030 is now 511 GW(e) of generating capacity, compared with 370 GW(e) today. The high projection is 807 GW(e); more than a doubling of present levels. Most of the 30 countries that already use nuclear power plan to expand their output. Growth targets have been raised significantly in China, India and the Russian Federation. In addition, according to the IAEA, some 50 countries - mostly in the developing world - have informed the IAEA that they might be interested in launching nuclear power programmes and 12 of these are actively considering nuclear power. Even in the high case projection, however, nuclear power's share of global power generation will go down from the current 16% level to 14% by 2030 and then rise to 22% by 2050, according to the projection

  9. The program of reactors and nuclear power plants

    International Nuclear Information System (INIS)

    Into de framework of the program of research reactors and nuclear power plants, the operating Argentine reactors are described. The uses of the research reactors in Argentina are summarized. The reactors installed by Argentina in other countries (Peru, Algeria, Egypt) are briefly described. The CAREM project for the design and construction of an innovator small power reactor (27 MWe) is also described in some detail. The next biennial research and development program for reactor is briefly outlined

  10. RB research nuclear reactor, Annual report for 1989, I - III

    International Nuclear Information System (INIS)

    This report is made of three parts. Part one contains a short description of the reactor, reactor operation, incidents, status of reactor equipment and components (nuclear fuel, heavy water, reactor vessel, heavy water circulation system, electronic, electric and mechanical equipment, auxiliary systems and Vax-8250 computer). It includes dosimetry and radiation protection data, personnel and financial data. Second part of this report in concerned with maintenance of reactor components and instrumentation. Part three includes data about reactor utilization during 1989

  11. Chernobyl: disinformation. 2000 dead in Chernobyl: they were made by journalists

    International Nuclear Information System (INIS)

    After having briefly recalled the scenario which resulted in the Chernobyl accident, the differences between the Chernobyl reactor and the French graphite-based reactors, and that some modifications have been introduced in the alarm system of the Bugey reactor, the author reviews the chronology of events and information after the accident. He recalls the Soviet way to deal with the information, states that the authorities did not immediately understand the severity of the accident. He notably outlines and comments a statement reporting that 2.000 people died just after the accident. Thus, it appears that both sides could be criticized, the Russian side for its slow reaction, and the Western side for disinformation. He also denounces a fake documentary report made by a French journalist (images pretended to have been taken in Chernobyl had been in fact shot in an Italian factory). He also evokes the reactions of people in front of this kind information about risks of exposure. He analyses the content of an article written by a French journalist who denounced some kinds of plots elaborated by oil companies, by the USSR, by anti-nuclear activists

  12. Official announcement of an executive agreement between Federal German Government and Land governments, concerning payment of compensation for reasons of equity, for losses as result of the Chernobyl reactor accident; and announcement of the pertinent administrative directive

    International Nuclear Information System (INIS)

    The Federal Republic of Germany and the Lands concluded an executive agreement on compensation to be paid for reasons of equity, for losses incurred as a consequence of the Chernobyl reactor accident, and on the pertinent administration directive defining general principles of fair compensation for losses induced by the Chernobyl reactor accident (Fair Compensation Directive). The directive will be issued by each Land government for its province, and published in the pertinent regional, official gazettes. The full texts of the executive agreement and the Fair Compensation Directive are given below. (orig.)

  13. Field and laboratory nuclear techniques in radionuclide transport studies: Methodology, technology and case studies in the territory of the Russian Federation exposed to radioactive contamination due to the Chernobyl accident

    International Nuclear Information System (INIS)

    The nuclear techniques used in studying migration mechanisms and characteristics of radionuclides released into the environment as a consequence of the Chernobyl accident are described and evaluated. These include nuclear well logging in profiling soil density, moisture and clay particle content; artificial isotope tracer (including multitracer) technology for simultaneous in situ determination of the velocity of tritiated water and injected/released radionuclide (90Sr, 137Cs) movement; their diffusion/dispersion coefficients and Kd and retardation factors (R); a Chernobyl radionuclide survey of soils, sediments, surface waters and groundwaters to estimate the radioecological conditions and consequences; natural stable (D, 18O, 13C) and radioactive (T, 14C, 226Ra, 228Ra) isotope methods for evaluating the genesis and mean residence times of groundwaters (MRTw) and contaminants (radionuclides) (MRTc). For the assessment of the vulnerability and the prediction of possible contamination of exploited shallow and deeper groundwaters by the reactor radionuclides (mainly, 137Cs and 90Sr), two approaches were applied: (1) determination of the mean residence time of groundwater by means of the environmental tritium data and the retardation factor (determined by laboratory and field tracer experiments); (2) direct experimental determination of the recharge rate and the migration characteristics of radionuclides in the unsaturated zone. (author). 17 refs, 7 figs, 8 tabs

  14. Thermoacoustic Thermometry for Nuclear Reactor Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    James A. Smith; Dale K. Kotter; Steven L. Garrett; Randall A. Ali

    2013-06-01

    On Friday, March 11, 2011, at 2:46pm (Japan Standard Trme), the Tohoku region on the east coast of northern Japan experi­enced what would become known as the largest earthquake in the country's history at magnitude 9.0 on the Richter scale. The Fukushima Daiichi nuclear power plant suffered exten­sive and irreversible damage. Six operating units were at the site, each with a boiling water reactor. When the earthquake struck, three of the six reactors were operating and the others were in a periodic inspection outage phase. In one reactor, all of the fuel had been relocated to a spent fuel pool in the reactor building. The seismic acceleration caused by the earthquake brought the three operating units to an automatic shutdown. Since there was damage to the power transmission lines, the emergency diesel generators (EDG) were automat­ically started to ensure continued cooling of the reactors and spent fuel pools. The situation was under control until the tsunami hit about forty-five minutes later with a maximum wave height of approximately 15 meters, which was three times taller than the sea wall of 5m. The influx of water submerged the EDGs, the electrical switchgear, and dc batteries, resulting in the total loss of power to five of the six reactors. The flooding also resulted in the loss of instrumentation that would have other­ wise been used to monitor and control the emergency. The ugly aftermath included high radiation exposure to operators at the nuclear power plants and early contamina­tion of food supplies and water within several restricted areas in Japan, where high radiation levels have rendered them un­safe for human habitation. While the rest of the story will remain a tragic history, it is this part of the series of unfortunate events that has inspired our research. It has indubitably highlighted the need for a novel sensor and instrumentation system that can withstand similar or worse conditions to avoid future catastrophe and assume damage

  15. Atmospheric transport of radionuclides emitted due to wildfires near the Chernobyl Nuclear Power Plant in 2015

    Science.gov (United States)

    Evangeliou, Nikolaos; Zibtsev, Sergey; Myroniuk, Viktor; Zhurba, Marina; Hamburger, Thomas; Stohl, Andreas; Balkanski, Yves; Paugam, Ronan; Mousseau, Timothy A.; Møller, Anders P.; Kireev, Sergey I.

    2016-04-01

    In 2015, two major fires in the Chernobyl Exclusion Zone (CEZ) have caused concerns about the secondary radioactive contamination that might have spread over Europe. The total active burned area was estimated to be about 15,000 hectares, of which 9000 hectares burned in April and 6000 hectares in August. The present paper aims to assess, for the first time, the transport and impact of these fires over Europe. For this reason, direct observations of the prevailing deposition levels of 137Cs and 90Sr, 238Pu, 239Pu, 240Pu and 241Am in the CEZ were processed together with burned area estimates. Based on literature reports, we made the conservative assumption that 20% of the deposited labile radionuclides 137Cs and 90Sr, and 10% of the more refractory 238Pu, 239Pu, 240Pu and 241Am, were resuspended by the fires. We estimate that about 10.9 TBq of 137Cs, 1.5 TBq of 90Sr, 7.8 GBq of 238Pu, 6.3 GBq of 239Pu, 9.4 GBq of 240Pu and 29.7 GBq of 241Am were released from both fire events. These releases could be classified as of "Level 3" on the relative INES (International Nuclear Events Scale) scale, which corresponds to a serious incident, in which non-lethal deterministic effects are expected from radiation. To simulate the dispersion of the resuspended radionuclides in the atmosphere and their deposition onto the terrestrial environment, we used a Lagrangian dispersion model. Spring fires redistributed radionuclides over the northern and eastern parts of Europe, while the summer fires also affected Central and Southern Europe. The more labile elements escaped more easily from the CEZ and then reached and deposited in areas far from the source, whereas the larger refractory particles were removed more efficiently from the atmosphere and thus did mainly affect the CEZ and its vicinity. For the spring 2015 fires, we estimate that about 80% of 137Cs and 90Sr and about 69% of 238Pu, 239Pu, 240Pu and 241Am were deposited over areas outside the CEZ. 93% of the labile and 97% of

  16. What drives innovation in nuclear reactors technologies? An empirical study based on patent counts

    International Nuclear Information System (INIS)

    This paper examines the evolution of innovation in nuclear power reactors between 1974 and 2008 in twelve OECD countries and assesses to what extent nuclear innovation has been driven by economic incentives, political decisions and safety regulation considerations. We use priority patent applications related to Nuclear Power Plants (NPPs) as a proxy for innovating activity. Our results highlight that nuclear innovation is partly driven by the conventional paradigm where both demand-pull, measured by NPPs constructions in the innovating country and in the rest of the world, and technology-push, measured by Research and Development (R and D) expenditures specific to NPPs, have a positive and significant impact on innovation. Our results also evidence that the impact of public R and D expenditures and national NPPs construction on innovation is stronger when the quality of innovation, measured by forward patent citations, is taken into account, and have a long run positive impact on innovation through the stock of knowledge available to innovators. In contrast, we show that political decisions following the Three Miles Island and Chernobyl nuclear accidents, measured by NPPs cancellations, have a negative impact on nuclear innovation. Finally, we find that the nuclear safety authority has an ambivalent effect on innovation. On one hand, regulatory inspections have a positive impact on innovation, one the other hand, regulatory decisions to temporarily close a NPP have an adverse impact on innovation. (author)

  17. Nuclear power reactors and hydrogen storage systems

    International Nuclear Information System (INIS)

    Among conclusions and results come by, a nuclear-electric-hydrogen integrated power system was suggested as a way to prevent the energy crisis. It was shown that the hydrogen power system using nuclear power as a leading energy resource would hold an advantage in the current international situation as well as for the long-term future. Results reported provide designers of integrated nuclear-electric-hydrogen systems with computation models and routines which will allow them to explore the optimal solution in coupling power reactors to hydrogen producing systems, taking into account the specific characters of hydrogen storage systems. The models were meant for average computers of a type easily available in developing countries. (author)

  18. Advanced nuclear reactor public opinion project

    International Nuclear Information System (INIS)

    This Interim Report summarizes the findings of our first twenty in-depth interviews in the Advanced Nuclear Reactor Public Opinion Project. We interviewed 6 industry trade association officials, 3 industry attorneys, 6 environmentalists/nuclear critics, 3 state officials, and 3 independent analysts. In addition, we have had numerous shorter discussions with various individuals concerned about nuclear power. The report is organized into the four categories proposed at our April, 1991, Advisory Group meeting: safety, cost-benefit analysis, science education, and communications. Within each category, some change of focus from that of the Advisory Group has been required, to reflect the findings of our interviews. This report limits itself to describing our findings. An accompanying memo draws some tentative conclusions

  19. Advanced nuclear reactor public opinion project

    Energy Technology Data Exchange (ETDEWEB)

    Benson, B.

    1991-07-25

    This Interim Report summarizes the findings of our first twenty in-depth interviews in the Advanced Nuclear Reactor Public Opinion Project. We interviewed 6 industry trade association officials, 3 industry attorneys, 6 environmentalists/nuclear critics, 3 state officials, and 3 independent analysts. In addition, we have had numerous shorter discussions with various individuals concerned about nuclear power. The report is organized into the four categories proposed at our April, 1991, Advisory Group meeting: safety, cost-benefit analysis, science education, and communications. Within each category, some change of focus from that of the Advisory Group has been required, to reflect the findings of our interviews. This report limits itself to describing our findings. An accompanying memo draws some tentative conclusions.

  20. Designed porosity materials in nuclear reactor components

    Energy Technology Data Exchange (ETDEWEB)

    Yacout, A. M.; Pellin, Michael J.; Stan, Marius

    2016-09-06

    A nuclear fuel pellet with a porous substrate, such as a carbon or tungsten aerogel, on which at least one layer of a fuel containing material is deposited via atomic layer deposition, and wherein the layer deposition is controlled to prevent agglomeration of defects. Further, a method of fabricating a nuclear fuel pellet, wherein the method features the steps of selecting a porous substrate, depositing at least one layer of a fuel containing material, and terminating the deposition when the desired porosity is achieved. Also provided is a nuclear reactor fuel cladding made of a porous substrate, such as silicon carbide aerogel or silicon carbide cloth, upon which layers of silicon carbide are deposited.

  1. Chernobyl, 12 years later; Tchernobyl, douze ans apres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-04-01

    This report draws an account of the consequences of Chernobyl accident 12 years after the disaster. It is made up of 7 chapters whose titles are: (1) Some figures about Chernobyl accident, (2) The 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) The Franco-German cooperation, and (7) Glossary.

  2. Radioactivity in forests and single trees caused by the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    The activity deposited per km2 in the Karlsruhe region is comparable with the sum of aerosols released from all nuclear power plants in the Federal Republic of Germany. Results of measurements performed in 1986 on leaf and needle samples are compared to the corresponding results obtained in 1987. The behavior of cesium activity in trees is discussed. In addition the results of measurements made in 1987 on small vegetation, especially mushrooms, are indicated. The Cs-activity expected to be found in the meat of deer of the same region is estimated. (orig./HP)

  3. The biological effects of low doses of ionizing radiation: Chernobyl nuclear accident and spreading of hemoblastoses in Moldova

    International Nuclear Information System (INIS)

    The study of morbidity by hematologic neoplasms before and after the Chernobyl Nuclear Accident in regions of Moldova differently affected by radiation and some immuno- metabolic disturbances in people from these regions was the object of the present work. An increase of standardized (world) incidence of hemoblastoses during the 10 years after the Accident, especially in children under 10 years old and in persons over 60 years old, was registered. A decrease of immunologic indices and the alterations of the amino acids content in blood serum and erythrocytes of healthy persons from the regions with higher radioactive impact after the Accident were established as well. A possible correlation between mentioned modifications are discussed. (author)

  4. ENC86: Under the shadow of Chernobyl?

    International Nuclear Information System (INIS)

    The combined meeting of the European Nuclear Society, the American Nuclear Society and FORATOM in Geneva from 1-6 June had the distinction of being the first major meeting of the nuclear industry after Chernobyl. It was so close that all the papers had been written before the accident. Nothing, in the sense that Chernobyl was not a western reactor, so in detail very little technical information will emerge which will affect western procedures for reactor design or safety assessment given the reviews that have occurred since Three Mile Island. We will expect to learn a great deal about the handling of emergencies, institutional and organisational arrangements, and potentially could learn a great deal of scientific and radiological interest, but these are all matters of detail, not principle, so nothing has changed. Everything, in the sense that the public perception has changed dramatically for the worse. The public has been shocked by the far-reaching effects of the accident. Whether the change is sufficient to challenge the future development of nuclear power is not yet clear, but the matter is certainly open for debate, at least in some countries. This dual view was reflected throughout the conference. The major speakers in the plenary sessions dwelt principally on the effects of Chernobyl. The speakers in the technical and numerous poster sessions did not, in general, have to make any changes to their presentations or to the detailed scientific material. There was an anti-nuclear demonstration at the conference headquarters on the Sunday evening which prevented some participants reaching the opening reception. This was organised by an umbrella anti-nuclear organisation calling itself 'Contratom'. The first social event having been substantially disrupted, it was noticeable that none of the technical sessions of the conference throughout the rest of the week were affected in the slightest. The views of the major speakers can be grouped into three areas. Firstly

  5. Next generation advanced nuclear reactor designs

    International Nuclear Information System (INIS)

    Growing energy demand by technological developments and the increase of the world population and gradually diminishing energy resources made nuclear power an indispensable option. The renewable energy sources like solar, wind and geothermal may be suited to meet some local needs. Environment friendly nuclear energy which is a suitable solution to large scale demands tends to develop highly economical, advanced next generation reactors by incorporating technological developments and years of operating experience. The enhancement of safety and reliability, facilitation of maintainability, impeccable compatibility with the environment are the goals of the new generation reactors. The protection of the investment and property is considered as well as the protection of the environment and mankind. They became economically attractive compared to fossil-fired units by the use of standard designs, replacing some active systems by passive, reducing construction time and increasing the operation lifetime. The evolutionary designs were introduced at first by ameliorating the conventional plants, than revolutionary systems which are denoted as generation IV were verged to meet future needs. The investigations on the advanced, proliferation resistant fuel cycle technologies were initiated to minimize the radioactive waste burden by using new generation fast reactors and ADS transmuters.

  6. Radiation monitoring and actions in Finland after reactor accident in Chernobyl

    International Nuclear Information System (INIS)

    In the event of a radiation hazard, the authorities participating in radiation control, act in accordance with a guide issued by the Ministry of the Interior. The guide defines the notification and warning limits to be applied between the various bodies. The institutes taking part in radiation control are the Institute of Seismology, the Finnish Meteorological Institute, the Defence Forces, the Ministry of the Interior, and the Finnish Centre for Radiation and Nuclear Safety. The continuously operated radiation monitoring stations of the Defence Forces and the Ministry of the Interior are obliged to notify the other institutes participating in the control if the dose rate of external radiation reaches the value 0.07 mR/h (0,7 microSv/h) and all radiation monitoring stations are obliged to give a warning to the other bodies if the dose rate reaches the value 1 mR/h (10 microSv/h). The Finnish Centre for Radiation and Nuclear Safety has the duty to report exceptional findings and to warn the other institutes as deemed appropriate. According to the guide, population must be warned of a sudden radiation hazard at least when the dose rate has reached the value 200 microSv/h. An alarm for seeking immediate shelter must be given at least when the dose rate exceeds the value 2000 microSv/h

  7. About Chernobyl - Twenty Years Later

    International Nuclear Information System (INIS)

    The author discusses the reactor accident of Chernobyl, the information on its consequences so contradictory in the former USSR countries, the status of the effects observed, the forecasting concerning the onset of cancers in the coming years among the populations that were exposed to radiations, the public opinion facing the pessimists. He concludes on the lessons which can be drawn from Chernobyl. (A.L.B.)

  8. Chernobyl and our health

    International Nuclear Information System (INIS)

    The health impacts in Sweden of the Chernobyl accident are discussed in this booklet. Five experts of different relevant fields (biology, radioecology, nuclear physics and psychology) give their views on probable radiation doses and health effects from these doses, contamination of food chains etc. (L.E.)

  9. Hypertension and left ventricular hypertrophy in liquidators of consequences of the Chernobyl nuclear accident

    International Nuclear Information System (INIS)

    Echocardiography was used for the study of prevalence of left ventricular hypertrophy in 839 liquidators of consequences of the Chernobyl accident. Prevalence of left ventricular hypertrophy (left ventricular myocardial mass 134 g/m2) was 10.3, 13.4 and 22.5 % in liquidators with normal blood pressure, borderline hypertension and hypertension, respectively. Liquidators with normal blood pressure had significantly greater left ventricular myocardial mass than normotensive men from general population while liquidators and non liquidators with hypertension had equal values of this parameter

  10. Microflora of nuclear research reactor pool water

    International Nuclear Information System (INIS)

    The circulation of pool water through the nuclear reactor core produces a bactericidal effect on the microflora due to the influence of various kinds of radiation. The microbe contents return to their initial level in 2 to 4 months after the circulation has stopped. The microflora comprises mainly cocci in large numbers, G-positive rods and fungi, and lower amounts of G-negative rods as compared with the water with which the reactor pool was initially filled. Increased amounts are present of radiation-resistant forms exhibiting intense production of catalase and nuclease. Supposedly, the presence of these enzymes is in some way beneficial to the microbes in their survival in the high-radiation zones. (author). 1 fig., 2 tabs., 12 refs

  11. Eugene Wigner, The First Nuclear Reactor Engineer

    Science.gov (United States)

    Weinberg, Alvin M.

    2002-04-01

    All physicists recognize Eugene Wigner as a theoretical physicist of the very first rank. Yet Wigner's only advanced degree was in Chemical Engineering. His physics was largely self-taught. During WWII, Wigner brilliantly returned to his original occupation as an engineer. He led the small team of theoretical physicists and engineers who designed, in remarkable detail, the original graphite-moderated, water-cooled Hanford reactor, which produced the Pu239 of the Trinity and Nagasaki bombs. With his unparalleled understanding of chain reactors (matched only by Fermi) and his skill and liking for engineering, Wigner can properly be called the Founder of Nuclear Engineering. The evidence for this is demonstrated by a summary of his 37 Patents on various chain reacting systems.

  12. REACTOR PHYSICS MODELING OF SPENT NUCLEAR RESEARCH REACTOR FUEL FOR SNM ATTRIBUTION AND NUCLEAR FORENSICS

    Energy Technology Data Exchange (ETDEWEB)

    Sternat, M.; Beals, D.; Webb, R.; Nichols, T.

    2010-06-09

    Nuclear research reactors are the least safeguarded type of reactor; in some cases this may be attributed to low risk and in most cases it is due to difficulty from dynamic operation. Research reactors vary greatly in size, fuel type, enrichment, power and burnup providing a significant challenge to any standardized safeguard system. If a whole fuel assembly was interdicted, based on geometry and other traditional forensics work, one could identify the material's origin fairly accurately. If the material has been dispersed or reprocessed, in-depth reactor physics models may be used to help with the identification. Should there be a need to attribute research reactor fuel material, the Savannah River National Laboratory would perform radiochemical analysis of samples of the material as well as other non-destructive measurements. In depth reactor physics modeling would then be performed to compare to these measured results in an attempt to associate the measured results with various reactor parameters. Several reactor physics codes are being used and considered for this purpose, including: MONTEBURNS/ORIGEN/MCNP5, CINDER/MCNPX and WIMS. In attempt to identify reactor characteristics, such as time since shutdown, burnup, or power, various isotopes are used. Complexities arise when the inherent assumptions embedded in different reactor physics codes handle the isotopes differently and may quantify them to different levels of accuracy. A technical approach to modeling spent research reactor fuel begins at the assembly level upon acquiring detailed information of the reactor to be modeled. A single assembly is run using periodic boundary conditions to simulate an infinite lattice which may be repeatedly burned to produce input fuel isotopic vectors of various burnups for a core level model. A core level model will then be constructed using the assembly level results as inputs for the specific fuel shuffling pattern in an attempt to establish an equilibrium cycle

  13. Dielectric Heaters for Testing Spacecraft Nuclear Reactors

    Science.gov (United States)

    Sims, William Herbert; Bitteker, Leo; Godfroy, Thomas

    2006-01-01

    A document proposes the development of radio-frequency-(RF)-driven dielectric heaters for non-nuclear thermal testing of the cores of nuclear-fission reactors for spacecraft. Like the electrical-resistance heaters used heretofore for such testing, the dielectric heaters would be inserted in the reactors in place of nuclear fuel rods. A typical heater according to the proposal would consist of a rod of lossy dielectric material sized and shaped like a fuel rod and containing an electrically conductive rod along its center line. Exploiting the dielectric loss mechanism that is usually considered a nuisance in other applications, an RF signal, typically at a frequency .50 MHz and an amplitude between 2 and 5 kV, would be applied to the central conductor to heat the dielectric material. The main advantage of the proposal is that the wiring needed for the RF dielectric heating would be simpler and easier to fabricate than is the wiring needed for resistance heating. In some applications, it might be possible to eliminate all heater wiring and, instead, beam the RF heating power into the dielectric rods from external antennas.

  14. Liquid-cooled nuclear reactor, especially a boiling water reactor

    International Nuclear Information System (INIS)

    A nuclear reactor with a special arrangement of fuel rods in the core is designed. Each fuel element has its shaft which is made of sheets, has the same cross section as the fuel element and protrudes at least the length of the control rod above the reactor core. Made of a zirconium alloy in the core area and of stainless steel above it, the shaft is equipped with channels for sliding the rods in and out and serves to spatially secure the position of the rods. Coolant flow is provided by the chimney effect. The shaft can conveniently enclose the control rod drive. It can also serve to bear the water separator. Moreover, it can constitute a part of the casing which surrounds the fuel rods and keeps the fuel in an intimate contact with the coolant; the other part of this casing is constituted by inserted sheets which can conveniently have the shape of angles. The walls of neighboring shafts form a compartment accommodating a neutron absorber plate. (M.D.). 11 figs

  15. Proposed radiation hardened mobile vehicle for Chernobyl dismantlement and nuclear accident response

    International Nuclear Information System (INIS)

    Researchers are developing a radiation hardened, Telerobotic Dismantling System (TDS) to remediate the Chernobyl facility. To withstand the severe radiation fields, the robotic system, will rely on electrical motors, actuators, and relays proven in the Chernobyl power station. Due to its dust suppression characteristics and ability to cut arbitrary materials the authors propose using a water knife as the principle tool to slice up the large fuel containing masses. The front end of the robot will use a minimum number of moving parts by locating most of the susceptible and bulky components outside the work area. Hardened and shielded video cameras will be designed for remote control and viewing of the robotic functions. Operators will supervise and control robot movements based on feedback from a suite of sensory systems that would include vision systems, radiation detection and measurement systems and force reflection systems. A gripper will be instrumented with a variety of sensors (e.g. force, torque, or tactile), allowing varying debris surface properties to be grasped. The gripper will allow the operator to manipulate and segregate debris items without entering the radiologically and physically dangerous dismantlement operations area. The robots will initially size reduce the FCM's to reduce the primary sources of the airborne radionuclides. The robot will then remove the high level waste for packaging or decontamination, and storage nearby

  16. Prognosis for tumor morbidity among the salvaging personnel of the Chernobyl Nuclear Power Station

    International Nuclear Information System (INIS)

    Preduction of oncological disease rate in persons participating in the Chernobyl accident response for Russia group of liquidators (100000 persons) worked in 1986 is presented based on the assumption that neoplasm development period will consists subsequent 15 years (up to 2015). According to the official data in 1986, radiation doses to liquidators did not exceed 25 h. But real radiation doses to liquidators in most cases were not determined because of the absence of personal dosemeters. Radiation dose due to radionuclides inhalation was not accounted. Average dose to liquidators worked at the destroyed unit of Chernobyl NPP was 0.40 Sv in Summer, 1986, with the account of internal exposure. Data on the oncological disease rate, 12 years later the disaster, show that the neoplasms of respiratory organs and digestive organs are the most spread (36.2 and 28.3% correspondingly). Further, in the order of decreasing, the neoplasms follow of hematopoietic and lymphatic systems, urinary system and brain. Preventive therapy combination including A, C, E vitamins, provitamin A, selenium with lecithin in nut oil is recommended

  17. Solution of heat removal from nuclear reactors by natural convection

    Directory of Open Access Journals (Sweden)

    Zitek Pavel

    2014-03-01

    Full Text Available This paper summarizes the basis for the solution of heat removal by natural convection from both conventional nuclear reactors and reactors with fuel flowing coolant (such as reactors with molten fluoride salts MSR.The possibility of intensification of heat removal through gas lift is focused on. It might be used in an MSR (Molten Salt Reactor for cleaning the salt mixture of degassed fission products and therefore eliminating problems with iodine pitting. Heat removal by natural convection and its intensification increases significantly the safety of nuclear reactors. Simultaneously the heat removal also solves problems with lifetime of pumps in the primary circuit of high-temperature reactors.

  18. Water desalination by a fluidized bed nuclear reactor

    International Nuclear Information System (INIS)

    The great need for potable water in the world motivated the International Atomic Energy Agency (IAEA) to study the feasibility of nuclear seawater desalination. The consensus reached is that nuclear desalination is technically feasible, though cost and social acceptability are recognized as major problems to overcome. Here an inherently safe reactor with reduced cost is proposed to overcome these barriers. The reactor is a simple small modular nuclear reactor based on fluidized bed concept with passive cooling characteristics. (orig.)

  19. High-temperature and breeder reactors - economic nuclear reactors of the future

    International Nuclear Information System (INIS)

    The thesis begins with a review of the theory of nuclear fission and sections on the basic technology of nuclear reactors and the development of the first generation of gas-cooled reactors applied to electricity generation. It then deals in some detail with currently available and suggested types of high temperature reactor and with some related subsidiary issues such as the coupling of different reactor systems and various schemes for combining nuclear reactors with chemical processes (hydrogenation, hydrogen production, etc.), going on to discuss breeder reactors and their application. Further sections deal with questions of cost, comparison of nuclear with coal- and oil-fired stations, system analysis of reactor systems and the effect of nuclear generation on electricity supply. (C.J.O.G.)

  20. Implementing and measuring safety goals and safety culture. 1. Lessons to Learn from Three Mile Island, Chernobyl, and Tokaimura and the New Era of the European Nuclear Industry

    International Nuclear Information System (INIS)

    The purpose of this work is to analyze the reasons, the progression, and the improvements made in the aftermath of the world's three most disastrous and publicized nuclear accidents, as well as the lessons still to be learned. At present, the entire European electrical grid is integrated, and reactor manufacturers have become fewer and bigger. Until now, largely only the operators were accused of committing human errors. This contradicts the claim that later technological improvements offset the possibility of a repetition of the accident. To improve the safety culture, new complementary views are presented that previously had been overlooked. Technological improvements and safety culture deficiencies at the managerial level are still missing. Although the accidents at Three Mile Island (TMI), Chernobyl, and Tokaimura occurred on different continents at entirely different plants, these accidents share many common features in terms of precursors, progression, and succession. In the actual work, these common features are analyzed, and as a result, some recommendations are made. The results of the analyses show the following deficiencies in safety culture: 1. The precursors were not properly evaluated, and consequently, the correct conclusions were not deduced and applied. 2. The operators need much improved information about the status of the process that they control to be able to make the right decisions. 3. Operators must improve their awareness of observing deviations at an early stage to avoid accidents, and they also must improve their preparedness to meet the challenges of unexpected occurrences. 4. Management must learn to see the activities at the plant through the operators' eyes. 5. The price of the 'profit' of meeting time schedules by pressuring people is all to high for these practices to continue. The significance of the results is that they give direction to an improved safety culture, as follows: 1. Industry and management authority must assume

  1. Fluid sampling system for a nuclear reactor

    Science.gov (United States)

    Lau, L.K.; Alper, N.I.

    1994-11-22

    A system of extracting fluid samples, either liquid or gas, from the interior of a nuclear reactor containment utilizes a jet pump. To extract the sample fluid, a nonradioactive motive fluid is forced through the inlet and discharge ports of a jet pump located outside the containment, creating a suction that draws the sample fluid from the containment through a sample conduit connected to the pump suction port. The mixture of motive fluid and sample fluid is discharged through a return conduit to the interior of the containment. The jet pump and means for removing a portion of the sample fluid from the sample conduit can be located in a shielded sample grab station located next to the containment. A non-nuclear grade active pump can be located outside the grab sampling station and the containment to pump the nonradioactive motive fluid through the jet pump. 1 fig.

  2. Request for Naval Reactors Comment on Proposed Prometheus Space Flight Nuclear Reactor High Tier Reactor Safety Requirements and for Naval Reactors Approval to Transmit These Requirements to JPL

    Energy Technology Data Exchange (ETDEWEB)

    D. Kokkinos

    2005-04-28

    The purpose of this letter is to request Naval Reactors comments on the nuclear reactor high tier requirements for the PROMETHEUS space flight reactor design, pre-launch operations, launch, ascent, operation, and disposal, and to request Naval Reactors approval to transmit these requirements to Jet Propulsion Laboratory to ensure consistency between the reactor safety requirements and the spacecraft safety requirements. The proposed PROMETHEUS nuclear reactor high tier safety requirements are consistent with the long standing safety culture of the Naval Reactors Program and its commitment to protecting the health and safety of the public and the environment. In addition, the philosophy on which these requirements are based is consistent with the Nuclear Safety Policy Working Group recommendations on space nuclear propulsion safety (Reference 1), DOE Nuclear Safety Criteria and Specifications for Space Nuclear Reactors (Reference 2), the Nuclear Space Power Safety and Facility Guidelines Study of the Applied Physics Laboratory.

  3. Accumulation of transuranic elements in the aquatic biota of the Belarusian sector of contaminated area near the Chernobyl nuclear power plant - Accumulation of transuranic elements in aquatic biota of Belarusian sector of contaminated area of Chernobyl nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Golubev, Alexander; Mironov, Vladislav [International Sakharov Environmental University. Box 220070, 23 Dolgobrodskaya Street, Minsk, 220070 (Belarus)

    2014-07-01

    The evolution of nuclear contamination of Belarus territory after Chernobyl accident includes the four stages: 1. Iodine-neptunium stage, caused mainly by short-lived radionuclides {sup 131}I, {sup 239}Np and others with a half-life period of several weeks; II. Intermediate stage, caused by radionuclides with a half-life period of a year ({sup 144}Ce, {sup 106}Ru, {sup 134}Cs, etc.); III. Strontium-cesium stage, caused by {sup 90}Sr and {sup 137}Cs with a half-life period of about 30 years; IV. Plutonium-americium, caused by long-lived α-emitting radionuclides {sup 241}Am (period of half-life of 432 years) and {sup 239+240}Pu, having high radio and chemo-toxicity. According to forecasts, activity of {sup 241}Am to 2050 year will increase by 2.5 times and it will be the most important dose-related factor for the aquatic biota within the Chernobyl accident zone. In 2002 - 2008 years we have studied the accumulation of trans-uranic elements (TUE, {sup 241}Am, {sup 239+240}Pu) in basic components of water body ecosystems within the Chernobyl zone - non-flowing Perstok Lake, weak-flowing Borschevka flooding and small Braginka River. Among investigated components are water, bottom sediments, submerged macrophytes (Ceratophyllum submersum, Hydrocharis morsus-ranae, Lemna minor, Nuphar lutea, Stratiotes aloides), emergent macrophytes (Typha spp.), shellfish and fish. In the soil cover in the vicinity of the Perstok Lake activity of {sup 241}Am at present is equivalent to 300 - 600 Bq.kg{sup -1}, that is the basic source of its income to the lake. Radionuclides mobility in the water environment is higher than in the soil, that facilitates the rapid incorporation of {sup 241}Am to the trophic nets of water bodies and its removal by near-water animals in the terrestrial biotopes, including outside Chernobyl zone. Thus, the activity of {sup 241}Am in bottom sediments in the Perstok Lake and Borschevka flooding in 2008 year reach respectively 324 and 131 Bq.kg{sup -1}, and the

  4. Electrochemistry of Water-Cooled Nuclear Reactors

    International Nuclear Information System (INIS)

    This project developed a comprehensive mathematical and simulation model for calculating thermal hydraulic, electrochemical, and corrosion parameters, viz. temperature, fluid flow velocity, pH, corrosion potential, hydrogen injection, oxygen contamination, stress corrosion cracking, crack growth rate, and other important quantities in the coolant circuits of water-cooled nuclear power plants, including both Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs). The model is being used to assess the three major operational problems in Pressurized Water Reactors (PWR), which include mass transport, activity transport, and the axial offset anomaly, and provide a powerful tool for predicting the accumulation of SCC damage in BWR primary coolant circuits as a function of operating history. Another achievement of the project is the development of a simulation tool to serve both as a training tool for plant operators and as an engineering test-bed to evaluate new equipment and operating strategies (normal operation, cold shut down and others). The development and implementation of the model allows us to estimate the activity transport or ''radiation fields'' around the primary loop and the vessel, as a function of the operating parameters and the water chemistry

  5. Electrochemistry of Water-Cooled Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Macdonald, Dgiby; Urquidi-Macdonald, Mirna; Pitt, Jonathan

    2006-08-08

    This project developed a comprehensive mathematical and simulation model for calculating thermal hydraulic, electrochemical, and corrosion parameters, viz. temperature, fluid flow velocity, pH, corrosion potential, hydrogen injection, oxygen contamination, stress corrosion cracking, crack growth rate, and other important quantities in the coolant circuits of water-cooled nuclear power plants, including both Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs). The model is being used to assess the three major operational problems in Pressurized Water Reactors (PWR), which include mass transport, activity transport, and the axial offset anomaly, and provide a powerful tool for predicting the accumulation of SCC damage in BWR primary coolant circuits as a function of operating history. Another achievement of the project is the development of a simulation tool to serve both as a training tool for plant operators and as an engineering test-bed to evaluate new equipment and operating strategies (normal operation, cold shut down and others). The development and implementation of the model allows us to estimate the activity transport or "radiation fields" around the primary loop and the vessel, as a function of the operating parameters and the water chemistry.

  6. Nonlinear Ultrasonic Measurements in Nuclear Reactor Environments

    Science.gov (United States)

    Reinhardt, Brian T.

    Several Department of Energy Office of Nuclear Energy (DOE-NE) programs, such as the Fuel Cycle Research and Development (FCRD), Advanced Reactor Concepts (ARC), Light Water Reactor Sustainability, and Next Generation Nuclear Power Plants (NGNP), are investigating new fuels, materials, and inspection paradigms for advanced and existing reactors. A key objective of such programs is to understand the performance of these fuels and materials during irradiation. In DOE-NE's FCRD program, ultrasonic based technology was identified as a key approach that should be pursued to obtain the high-fidelity, high-accuracy data required to characterize the behavior and performance of new candidate fuels and structural materials during irradiation testing. The radiation, high temperatures, and pressure can limit the available tools and characterization methods. In this thesis, two ultrasonic characterization techniques will be explored. The first, finite amplitude wave propagation has been demonstrated to be sensitive to microstructural material property changes. It is a strong candidate to determine fuel evolution; however, it has not been demonstrated for in-situ reactor applications. In this thesis, finite amplitude wave propagation will be used to measure the microstructural evolution in Al-6061. This is the first demonstration of finite amplitude wave propagation at temperatures in excess of 200 °C and during an irradiation test. Second, a method based on contact nonlinear acoustic theory will be developed to identify compressed cracks. Compressed cracks are typically transparent to ultrasonic wave propagation; however, by measuring harmonic content developed during finite amplitude wave propagation, it is shown that even compressed cracks can be characterized. Lastly, piezoelectric transducers capable of making these measurements are developed. Specifically, three piezoelectric sensors (Bismuth Titanate, Aluminum Nitride, and Zinc Oxide) are tested in the Massachusetts

  7. Decision aid systems for nuclear reactors

    International Nuclear Information System (INIS)

    The development of new techniques, especially in the field of artificial intelligence, makes it possible to design more powerful computerized systems, supporting tasks related to the design and operation of nuclear power plants. The potential contribution and perspectives for the integration of such systems depend upon whether the improvement of existing plants, the design of next generation reactors or future projects are concerned. We present four systems which show the state-of-the-art as regards knowledge-based systems. The first system is related to the automatic generation of procedures dealing with loss of electrical sources. The second one aims at assisting the power plant utility in following the technical specifications during maintenance operations. Finally, the last two are designed to help an emergency team evaluate and forecast the evolution of an accidental situation in a nuclear reactor. Perspectives for on-line operator assistance are then discussed, as well as the main technical themes which will make it possible to design such systems. We conclude with the difficulties which are encountered upon the integration of these tools: their validation and task sharing between man and machine

  8. Methane reforming with fast nuclear reactor steam

    International Nuclear Information System (INIS)

    The paper considers the concept of utilizing nuclear fast reactor (FR) with a sodium coolant for methane steam reforming. Steam conditions of a power FR, e.g. the BN-600 now operating in Russia: steam pressure P=13.2 MPa and steam temperature T=500degC, do not absolutely comply with the catalytic reactor working parameters, which produces a synthetic gas (syngas), a mix of hydrogen and carbon oxide. In this connection, the present paper addresses a possibility of utilizing steam produced in one of three independent the BN-600 loops in an amount of 640 t/h for preparing a gas-steam mixture with T=500degC and its additional heating in a converter up to the operating temperature, T=850degC, at the expense of natural gas burning or electrical energy supplying. In this case, the fraction of burned natural gas burning or electrical energy supplying. In this case, the fraction of burned natural gas significantly decreases. It is estimated that steam parameters of the BN-600 afford to obtain ∼3·105 nm3/h of hydrogen. It is also considered a concept of nuclear heat transfer to remote regions to be achieved with the aid of syngas incoming from the converter, its cooling further and transmitting through a pipeline to the place of its utilization, where it is restored into methane with the heat extraction. (author)

  9. Data acquisition system for nuclear reactor environment

    International Nuclear Information System (INIS)

    We have designed an online real time data acquisition system for nuclear reactor environment monitoring. Data acquisition system has eight channels of analog signals and one channel of pulsed input signal from detectors like GM Tube, or any other similar input. Connectivity between the data acquisition system and environmental parameters monitoring computer is made through a wireless data communication link of 151 MHz/100 mW RF power and 10 km maximum communication range for remote data telemetry. Sensors used are gamma ionizing radiation sensor made from CsI:Tl scintillator, atmospheric pressure sensor with +/-0.1 mbar precision, temperature sensor with +/-l milli degree Celsius precision, relative humidity with +/-0.1RH precision, pulse counts with +/-1 count in 0-10000 Hz count rate measurement precision and +/-1 count is accumulated count measurement precision. The entire data acquisition system and wireless telemetry system is 9 V battery powered and the device is to be fitted on a wireless controlled mobile robot for scanning the nuclear reactor zone from remote. Wireless video camera has been planned for integration into the existing system on a later date for moving the robotics environmental data acquisition system beyond human vision reach. System development cost is Rs.25 Lacs and has been developed for Department of Atomic Energy, Government of India and Indian Defense use. (author)

  10. Nuclear reactors: Notifiable events in 2002

    International Nuclear Information System (INIS)

    Notifiable events in nuclear power plants in the Federal Republic of Germany are reported to the regulatory authorities under the Atomic Energy Act in accordance with standardized national reporting criteria, and are recorded centrally. The binding legal provisions covering these reports can be found in the Nuclear Safety Commissioner and Reporting Ordinance (AtSMV). On an international level, events are classified in the International Nuclear Event Scale (INES) comprising eight levels. The four quarterly reports covering 2002 include 167 notifiable events for nuclear power plants in operation and in the decommissioning stage. Of these events, 157 are in reporting category N (normal), while ten are in reporting category E (urgent). No events have been reported in category S (immediate). 154 events are INES level 0, 13 events are INES level 1. 13 category-N events were reported for research reactors. All of them are INES level 0. There were no releases of radioactive material above the licensed levels for ex-vent air and liquid effluents. (orig.)

  11. The Chernobyl accident ten years later

    International Nuclear Information System (INIS)

    On April 26, 1986 at 1:23 AM a fire and explosion occurred at the fourth unit of the Chernobyl Nuclear Power Plant Complex, located in the Ukraine, that resulted in the destruction of the reactor core and most of the building in which it was housed. Several environmental impacts resulting from the accident will be discussed in this paper, which will include the effects on plant and wild life, radioactive waste generated and stored or disposed of, effects of evacuations relating to residents within the subsequently established 10km and 30km control zones, impacts of the emergency containment structure (sarcophagus), and potential effects on world opinion and future development of nuclear power. As an immediate result of the fire, 31 people died (2 from the fire ampersand smoke, and 29 from excessive radiation); 237 cases of acute radiation sickness occurred; the total fatalities based upon induced chronic diseases as a result of the accident is unknown: more than 100,000 people were evacuated from within the subsequently established 30 km control zone; in excess of 50 million curies of radionuclides that included finely dispersed nuclear fuel, fragments of graphite, concrete and other building materials were released from the reactor into the environment; an estimated one million cubic meters of radioactive waste were generated (LLW, ILW, HLW); more than 5000 tons of materials (sand, boron, dolomite, cement, and lead) were used to put the fire out by helicopter; shutdown of the adjacent power plants were performed; and other environmental impacts occurred. The Chernobyl Nuclear Power Plant Unit No 4 is an RBMK-1000. It initiated operations in 1983, it was a 1000 MWe with a power output of 3200 MW(th), the reactor core contained 190 MT of fuel, with 1659 assemblies (plus 211 control rods), the average burnup rate was 10.3 MWd/kg, and the reactor operated on a continuous basis with maintenance and fuel reload performed during operations

  12. Reconversion of nuclear weapons

    CERN Document Server

    Kapitza, Sergei P

    1993-01-01

    The nuclear predicament or nuclear option. Synopsis of three lectures : 1- The physical basis of nuclear technology. Physics of fission. Chain reaction in reactors and weapons. Fission fragments. Separration of isotopes. Radiochemistry.2- Nuclear reactors with slow and fast neutrons. Power, size, fuel and waste. Plutonium production. Dose rate, shielding and health hazard. The lessons of Chernobyl3- Nuclear weapons. Types, energy, blast and fallout. Fusion and hydrogen bombs. What to do with nuclear weapons when you cannot use them? Testing. Nonmilittary use. Can we get rid of the nuclear weapon? Nuclear proliferation. Is there a nuclear future?

  13. 让切尔诺贝利核事故的警钟长鸣——纪念切尔诺贝利核事故25周年%Let the Chernobyl Nuclear Accident Alarm Bells Ring Forever

    Institute of Scientific and Technical Information of China (English)

    李宗明

    2011-01-01

    一次严重事故发生后总引发业内人士颇有兴趣的讨论并相应地对核安全框架做出修改,但每次重大事故的起因并非相同,触及到的问题也不一样。25年前的切尔诺贝利核事故让世界震惊;25年中5个堆发生堆熔远远超出了国际上对严重事故发生概率的规定;25年中因堆熔事故11个机组报废、两个厂址变成了人们不敢前往的地方。面对这一切,我们需要有全新的核安全思维。%Abstract:Whenever a serious accident the scientific community of experts is quite interested in general discussion on nuclear safety and accordingly makes changes to the nuclear safety framework,but every major cause of the accident is not the same,and the problems involved are not the same.25 years ago,the Chernobyl nuclear accident shocked the world.In the past 25 years,reactor core melt occurred in five reactors,far beyond the international provisions to the probability of a serious accident.In the past 25 years due to melting reactor accident 11 reactor units scrapped,two sites became places where people dare not go.With all this,we need new nuclear safety thinking.

  14. Nuclear-safety criteria and specifications for space nuclear reactors

    International Nuclear Information System (INIS)

    The policy of the United States for all US nuclear power sources in space is to ensure that the probability of release of radioactive material and the amounts released are such that an undue risk is not presented, considering the benefits of the mission. The objective of this document is to provide safety criteria which a mission/reactor designer can use to help ensure that the design is acceptable from a radiological safety standpoint. These criteria encompass mission design, reactor design, and radiological impact limitation requirements for safety, and the documentation required. They do not address terrestrial operations, occupational safety or system reliability except where the systems are important for radiological safety. Specific safety specifications based on these criteria shall also be generated and made part of contractual requirements

  15. The Chernobyl nuclear accident: environmental radioactivity monitoring at the LENA site

    International Nuclear Information System (INIS)

    Air pumping and filtration stations nearby the LENA site, routinely active for air radioactivity monitoring, were alerted on April 28, 1986 to look for fission products coming from U.S.S.R. after the Chernobyl accident according to weather forecast. Air filters were submitted to direct gamma ray spectrometry and fission products detected. After May 1st 1986, when the maximum radionuclide concentration in air was observed, an environmental radioactivity monitoring program was started. Several matrices such as milk, soil, grass, vegetables, tap and rain water, were systematically analyzed. At the moment the program is still active but only air, milk, vegetables and meat are periodically analyzed by gamma ray spectrometry. Results, distributions and correlations are presented and discussed. (author)

  16. Radioecological transfer of {sup 137}Cs from ground deposition to man from Chernobyl debris and from nuclear weapons fallout in different Swedish populations

    Energy Technology Data Exchange (ETDEWEB)

    Raeaef, C.L. [Malmoe Univ. Hospital, Lund Univ., Dept. of Radiation Physics, Malmoe (Sweden)

    2005-07-01

    A comparison of the estimated committed effective dose per unit activity deposition on ground was made between different critical groups in Sweden. The time-integrated aggregate transfer of {sup 137}Cs for the global fallout was 2-3 times higher than from Chernobyl debris for Swedish urban populations. For reindeer herders this difference is even more marked, with a factor of three to four higher time-integrated transfer factor of nuclear weapons fallout. Considering the transfer of Chernobyl {sup 137}Cs debris the time-integrated transfer factor appears to be more than 25 times higher for reindeer herders in Sweden than for the urban reference groups. An even more pronounced relative difference between the time integrated aggregate transfer was observed between reindeer herders and urban reference populations for the pre-Chernobyl fallout (a factor of 30). The projected committed effective dose from internal contamination of Chernobyl {sup 137}Cs per unit activity deposition is observed to be 2030 {mu}Sv/kBq m{sup -2}. The highest values in Sweden are obtained for reindeer herders with an estimated radioecological transfer of 0.5 mSv/kBq m{sup -2}. (au)

  17. Health and environmental consequences of the Chernobyl nuclear power plant accident

    International Nuclear Information System (INIS)

    An assessment of the impact of the Chernobyl accident on the Northern Hemisphere is presented in this report. It relies heavily on the USSR report presented to the International Atomic Energy Agency. There are gaps in present knowledge and, in some areas, uncertainties may never be completely resolved. What is clearly apparent at this time, however, is that on a large regional scale, the estimates of collective dose have a reasonable level of confidence. The associated potential health impacts have also been projected, together with a range of estimates. A brief description of the tragic consequences to the heroic firefighting and rescue personnel is also provided, and valuable insights regarding acute exposures are developed. Much early effort was expended on estimation of the source term, especially for radiocesium and radioiodine. Several independent analyses are presented that are in reasonable agreement. Atmospheric transport of the radioactive material and its subsequent deposition provide a documented ''umbrella'' of the distributions that form the basic integration of this assessment. The estimates of radiological doses to selected Northern Hemisphere populations were employed in developing an integrated risk assessment of potential latent health effects using the most current models, parameters and risk coefficients. The estimates presented include lower- and upper-bound values, as well as the ''best'' or most realistic ranges. While many scientists believe that minuscule increases in risks to large populations are impossible to prove, it is essential that the magnitude of these possible risks be presented, if only to put an upper limit on the situation. It must be emphasized that while these are ''potential'' health effects, the values presented represent our best current assessment of the health and environmental detriment caused by the Chernobyl accident. 72 refs., 37 figs., 91 tabs

  18. The human sex odds at birth after the atmospheric atomic bomb tests, after Chernobyl, and in the vicinity of nuclear facilities: comment.

    Science.gov (United States)

    Krämer, Walter

    2012-05-01

    The recent claim made in this journal that nuclear bomb tests and the Chernobyl disaster caused distortions in the secondary sex ratio is shown to be a likely artifact of data mining, misused statistics, and misreading of the evidence. In particular, the concept of statistical "significance" and its limitations do not seem to be fully understood, and important confounding factors have not been accounted for.

  19. The human sex odds at birth after the atmospheric atomic bomb tests, after Chernobyl, and in the vicinity of nuclear facilities: comment.

    Science.gov (United States)

    Krämer, Walter

    2012-05-01

    The recent claim made in this journal that nuclear bomb tests and the Chernobyl disaster caused distortions in the secondary sex ratio is shown to be a likely artifact of data mining, misused statistics, and misreading of the evidence. In particular, the concept of statistical "significance" and its limitations do not seem to be fully understood, and important confounding factors have not been accounted for. PMID:22076251

  20. Reactor accident in Chernobyl

    International Nuclear Information System (INIS)

    The bibliography contains 1568 descriptions of papers devoted to Chernobylsk accident and recorded in ''INIS Atomindex'' to 30 June 1990. The descriptions were taken from ''INIS Atomindex'' and are presented in accordance with volumes of this journal (chronology of recording). Therefore all descriptions have numbers showing first the number of volume and then the number of record. The bibliography has at the end the detailed subject index consisting of 465 main headings and a lot of qualifiers. Some of them are descriptors taken from ''INIS Atomindex'' and some are key words taken from natural language. The index is in English as descriptions in the bibliography. (author)

  1. Nuclear reactors built, being built, or planned, 1988

    International Nuclear Information System (INIS)

    This document contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1988. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually from Washington Headquarters and field offices of DOE, from the US Nuclear Regulatory Commission, from the US reactor manufacturers who are the principal nuclear contractors for foreign reactor locations, from US and foreign embassies, and from foreign governmental nuclear departments. The book is divided into three major sections: Section 1 consists of a reactor locator map and reactor tables. Section 2 includes nuclear reactors that are operating, being built, or planned. Section 3 includes reactors that have been shut down permanently or dismantled

  2. Nuclear reactors built, being built, or planned: 1987

    International Nuclear Information System (INIS)

    Nuclear Reactors Built, Being Built, or Planned contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1987. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually for Washington headquarters and field offices of DOE; from the US Nuclear regulatory Commission; from the US reactor manufacturers who are the principal nuclear contractors for foreign reactor locations; from US and foreign embassies; and from foreign governmental nuclear departments. The major change in this revision involves the data related to shutdown and dismantled facilities. Because this information serves substantially different purposes, it has been accumulated in a separate section, ''Reactors and Facilities Shutdown or Dismantled.'' Cancelled reactors or reactors whose progress has been terminated at some stage before operation are included in this section

  3. Nuclear reactors built, being built, or planned 1993

    International Nuclear Information System (INIS)

    Nuclear Reactors Built, Being Built, or Planned contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1993. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually from Washington headquarters and field offices of DOE; from the US Nuclear Regulatory Commission (NRC); from the US reactor manufacturers who are the principal nuclear embassies; and from foreign governmental nuclear departments. The book consists of three divisions, as follows: (1) a commercial reactor locator map and tables of the characteristic and statistical data that follow; a table of abbreviations; (2) tables of data for reactors operating, being built, or planned; and (3) tables of data for reactors that have been shut down permanently or dismantled. The reactors are subdivided into the following parts: civilian, production, military, export, and critical assembly

  4. Nuclear reactors built, being built, or planned 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-08-01

    Nuclear Reactors Built, Being Built, or Planned contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1993. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually from Washington headquarters and field offices of DOE; from the US Nuclear Regulatory Commission (NRC); from the US reactor manufacturers who are the principal nuclear embassies; and from foreign governmental nuclear departments. The book consists of three divisions, as follows: (1) a commercial reactor locator map and tables of the characteristic and statistical data that follow; a table of abbreviations; (2) tables of data for reactors operating, being built, or planned; and (3) tables of data for reactors that have been shut down permanently or dismantled. The reactors are subdivided into the following parts: civilian, production, military, export, and critical assembly.

  5. The causes of the Chernobyl accident

    International Nuclear Information System (INIS)

    For the man in the street Chernobyl epitomizes the danger of nuclear energy but when we examine the causes of this accident we see that this drama is not intrinsically linked to the production of electricity from nuclear fission. The author sees 2 components in the Chernobyl event: the accident itself and its sanitary consequences. The author considers 3 main causes to the accident: -) a design that makes the reactor difficult to control, -) a series of 6 humane failures or breaking of operating rules, and -) political reasons: the largest possible budget was dedicated to plutonium production so any improvement for safety was considered as costly and secondary, moreover the religion of secrecy which was well spread in the ancient Soviet Union, prevented any scientific from knowing all the information concerning this type of reactor. As for the sanitary consequences, the author considers direct causes and underlying causes. The lack of information for the local population, the delay taken for iodine distribution or for the interdiction of farm products consumption are included in the direct causes. The slowness of Soviet bureaucracy, tight budgets and politico-scientific disputes are quoted among the underlying causes. (A.C.)

  6. Bhopal and Chernobyl: some comparisons

    International Nuclear Information System (INIS)

    An attempt is made to compare some aspects of the accidents at Bhopal and Chernobyl, their causes and consequences. There were design and management inadequacies in both cases, Maintenance inadequacies were plenty in Bhopal but not in Chernobyl. Written instructions were unsatisfactory in Bhopal. In Chernobyl the operators deliberately violated the instructions repeatedly; this compounded by the unsatisfactory nature of reactor design, led to the accident. Disaster management preparedness and emergency response were excellent at Chernobyl. At Bhopal the plant management was absolutely unprepared and contributed practically nothing to the emergency management; however, civil and military authorities did a splendid job. Immediate deaths in Bhopal are estimated to be 2,500 to 10,000 and the number affected 200,000. None of the plant staff were affected and all the casualties were in non-plant personnel living nearby. All the 31 deaths in Chernobyl were among the plant personnel. Although 135,000 persons living in a 30 Km zone round the reactor were evacuated and medically examined, none had to be hospitalised. The world scientific community seems to have forgotten Bhopal within a year or so after the accident, while Chernobyl continues to excite intense interest. Extensive knowledge of the biological effects of radiation helps to estimate the likely number of cancer and genetic effects from Chernobyl. Knowledge of Methyl iso cyanate (MIC) toxicology is woefully inadequate; recent evidence indicates the possibility of carcinogenic and mutagenic effects of MIC. Both at Bhopal and Chernobyl there are elaborate plans for detailed followup of the populations for several decades. (author). 17 refs., 3 tabs

  7. Migration of 137Cs from air to soil and plants in the Gulsvik area, Norway after the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    The migration of 137Cs from air to soil and vegetation after the Chernobyl accident has been studied using the concentrations measured in the Gulsvik area in Norway. The major part of the 137Cs deposition seems to be in the soil. An uptake of 137Cs from soil to plants through their root system is not a rapid process. Only a few percent of the deposition can be traced in plants. This seems to suggest that as far as 137Cs is concerned, an effect of the Chernobyl releases is not an acute but a long-term phenomenon. The 137Cs accumulation in soils is rather high, but doses not result in 137Cs levels in plants and diet higher than acceptable in Norway

  8. Spent nuclear fuel discharges from U.S. reactors 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-01

    Spent Nuclear Fuel Discharges from US Reactors 1994 provides current statistical data on fuel assemblies irradiated at commercial nuclear reactors operating in the US. This year`s report provides data on the current inventories and storage capacities at these reactors. Detailed statistics on the data are presented in four chapters that highlight 1994 spent fuel discharges, storage capacities and inventories, canister and nonfuel component data, and assembly characteristics. Five appendices, a glossary, and bibliography are also included. 10 figs., 34 tabs.

  9. Spent nuclear fuel discharges from U.S. reactors 1994

    International Nuclear Information System (INIS)

    Spent Nuclear Fuel Discharges from US Reactors 1994 provides current statistical data on fuel assemblies irradiated at commercial nuclear reactors operating in the US. This year's report provides data on the current inventories and storage capacities at these reactors. Detailed statistics on the data are presented in four chapters that highlight 1994 spent fuel discharges, storage capacities and inventories, canister and nonfuel component data, and assembly characteristics. Five appendices, a glossary, and bibliography are also included. 10 figs., 34 tabs

  10. Chernobyl, fifteen years after

    International Nuclear Information System (INIS)

    This work has been constituted around four questions: the future of the Chernobyl site, the damaged reactor, and the sarcophagus around it; the health consequences of the accident on the persons that have worked on the damaged reactor and on the population in the countries the most exposed to fallout,; the situation of contaminated territories around the power plant and their management today; the last question concerns especially the France with the consequences of the radioactive cloud and what we know about the health risks induced by this event. (N.C.)

  11. Prospects for applications of ship-propulsion nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Mitenkov, F.M.

    1994-10-01

    The use of ship-propulsion nuclear power reactors in remote areas of Russia is examined. Two ship reactors were analyzed: the KLT-40, a 170 MW-thermal reactor; and the KN-3, a 300 MW-thermal reactor. The applications considered were electricity generation, desalination, and drinking water production. Analyses showed that the applications are technically justified and could be economically advantageous. 5 refs., 9 figs., 1 tab.

  12. Uncertainties in the Anti-neutrino Production at Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Djurcic, Zelimir; Detwiler, Jason A.; Piepke, Andreas; Foster Jr., Vince R.; Miller, Lester; Gratta, Giorgio

    2008-08-06

    Anti-neutrino emission rates from nuclear reactors are determined from thermal power measurements and fission rate calculations. The uncertainties in these quantities for commercial power plants and their impact on the calculated interaction rates in {bar {nu}}{sub e} detectors is examined. We discuss reactor-to-reactor correlations between the leading uncertainties, and their relevance to reactor {bar {nu}}{sub e} experiments.

  13. Inherently safe reactors and a second nuclear era.

    Science.gov (United States)

    Weinberg, A M; Spiewak, I

    1984-06-29

    The Swedish PIUS reactor and the German-American small modular high-temperature gas-cooled reactor are inherently safe-that is, their safety relies not upon intervention of humans or of electromechanical devices but on immutable principles of physics and chemistry. A second nuclear era may require commercialization and deployment of such inherently safe reactors, even though existing light-water reactors appear to be as safe as other well-accepted sources of central electricity, particularly hydroelectric dams.

  14. Nuclear reactor materials at the atomic scale

    Directory of Open Access Journals (Sweden)

    Emmanuelle A. Marquis

    2009-11-01

    Full Text Available With the renewed interest in nuclear energy, developing new materials able to respond to the stringent requirements of the next-generation fission and future fusion reactors has become a priority. An efficient search for such materials requires detailed knowledge of material behaviour under irradiation, high temperatures and corrosive environments. Minimizing the rates of materials degradation will be possible only if the mechanisms by which it occurs are understood. Atomic-scale experimental probing as well as modelling can provide some answers and help predict in-service behaviour. This article illustrates how this approach has already improved our understanding of precipitation under irradiation, corrosion behaviour, and stress corrosion cracking. It is also now beginning to provide guidance for the development of new alloys.

  15. Research nuclear reactor start-up simulator

    International Nuclear Information System (INIS)

    This work presents the design and FPGA implementation of a research nuclear reactor start-up simulator. Its aim is to generate a set of signals that allow replacing the neutron detector for stimulated signals, to feed the measurement electronic of the start-up channels, to check its operation, together with the start-up security logic. The simulator presented can be configured on three independent channels and adjust the shape of the output pulses. Furthermore, each channel can be configured in 'rate' mode, where you can specify the growth rate of the pulse frequency in %/s. Result and details of the implementation on FPGA of the different functional blocks are given. (author)

  16. Control rod for a nuclear reactor

    International Nuclear Information System (INIS)

    A control rod assembly for a nuclear reactor is disclosed having a remotely disengageable coupling between the control rod and the control rod drive shaft. The coupling is actuated by first lowering then raising the drive shaft. The described motion causes axial repositioning of a pin in a grooved rotatable cylinder, each being attached to different parts of the drive shaft which are axially movable relative to each other. In one embodiment, the relative axial motion of the parts of the drive shaft is used either to couple or to uncouple the connection by forcing resilient members attached to the drive shaft into or out of shouldered engagement, respectively, with an indentation formed in the control rod

  17. Nuclear reactors transients identification and classification system

    International Nuclear Information System (INIS)

    This work describes the study and test of a system capable to identify and classify transients in thermo-hydraulic systems, using a neural network technique of the self-organizing maps (SOM) type, with the objective of implanting it on the new generations of nuclear reactors. The technique developed in this work consists on the use of multiple networks to do the classification and identification of the transient states, being each network a specialist at one respective transient of the system, that compete with each other using the quantization error, that is a measure given by this type of neural network. This technique showed very promising characteristics that allow the development of new functionalities in future projects. One of these characteristics consists on the potential of each network, besides responding what transient is in course, could give additional information about that transient. (author)

  18. Neutron measurements at nuclear power reactors [55

    CERN Document Server

    Scherpelz, R I

    2002-01-01

    Staff from the Pacific Northwest National Laboratory (operated by Battelle Memorial Institute), have performed neutron measurements at a number of commercial nuclear power plants in the United States. Neutron radiation fields at light water reactor (LWR) power plants are typically characterized by low-energy distributions due to the presence of large amounts of scattering material such as water and concrete. These low-energy distributions make it difficult to accurately monitor personnel exposures, since most survey meters and dosimeters are calibrated to higher-energy fields such as those produced by bare or D sub 2 O-moderated sup 2 sup 5 sup 2 Cf sources. Commercial plants typically use thermoluminescent dosimeters in an albedo configuration for personnel dosimetry and survey meters based on a thermal-neutron detector inside a cylindrical or spherical moderator for dose rate assessment, so their methods of routine monitoring are highly dependent on the energy of the neutron fields. Battelle has participate...

  19. Nuclear reactor safety and Federal regulation

    International Nuclear Information System (INIS)

    Public confidence in nuclear reactors requires that technical people translate complex safety information into a form that the public can understand well enough to make a judgment. An overall picture is drawn of the major areas of concern: (1) risks and safety measures, (2) government regulation, (3) licensing, (4) plant operation, (5) safety experience, and (6) quality assurance. Although the possibilities of a reactor core melting through the concrete containment barrier are slight, rigorous safety efforts are required. Government regulation and technical developments have developed concurrently so that the high standards set for government facilities can be carried over to commercial efforts. There are two stages in the licensing procedure: a construction permit and an operating license. Reviews of the proposed site, design, emergency cooling systems are all held, followed by a public hearing. Inspection and backfitting of new safety equipment are required in operating plants. The 60 plants now in operation have a good performance record, but good management for quality assurance increases safety and efficiency factors

  20. Structural integrity of nuclear reactor pressure vessels

    Science.gov (United States)

    Knott, John F.

    2013-09-01

    The paper starts from concerns expressed by Sir Alan Cottrell, in the early 1970s, related to the safety of the pressurized water reactor (PWR) proposed at that time for the next phase of electrical power generation. It proceeds to describe the design and operation of nuclear generation plant and gives details of the manufacture of PWR reactor pressure vessels (RPVs). Attention is paid to stress-relief cracking and under-clad cracking, experienced with early RPVs, explaining the mechanisms for these forms of cracking and the means taken to avoid them. Particular note is made of the contribution of non-destructive inspection to structural integrity. Factors affecting brittle fracture in RPV steels are described: in particular, effects of neutron irradiation. The use of fracture mechanics to assess defect tolerance is explained, together with the failure assessment diagram embodied in the R6 procedure. There is discussion of the Master Curve and how it incorporates effects of irradiation on fracture toughness. Dangers associated with extrapolation of data to low probabilities are illustrated. The treatment of fatigue-crack growth is described, in the context of transients that may be experienced in the operation of PWR plant. Detailed attention is paid to the thermal shock associated with a large loss-of-coolant accident. The final section reviews the arguments advanced to justify 'Incredibility of Failure' and how these are incorporated in assessments of the integrity of existing plant and proposed 'new build' PWR pressure vessels.

  1. In-core instrument for nuclear reactor

    International Nuclear Information System (INIS)

    This invention concerns, in particular, an improvement for in-core equipments in a nuclear reactor having sliding members. Deposition layers of particles of metal carbides and metal nitrides are formed at the sliding surface of members in the in-core eqiupments. The matrix materials constituting the members are melted under irradiation of laser beams to form a welded layer integrated with the deposition layer. In this way, since the thickness of the welded layer is remarkably thin as compared with of the substrate material, when the irradiation of the laser beams is interrupted, corrosion resistance in water at high temperature can be improved remarkably since the melted portion is quenched and no chromium carbide is deposited at the crystal boudary. Accordingly, due to excellent corrosion resistance and abrasion resistance of the welded layer relative to the in-core equipments in the reactor having sliding surfaces, sliding incapability does not occur between each of the members under crevice conditions. Accordingly, no withdrawal incapability for equipments, for example, neutron monitors should occur upon periodical inspection. (I.S.)

  2. Nuclear reactors built, being built, or planned: 1989

    International Nuclear Information System (INIS)

    Nuclear Reactors Built, Being Built, or Planned contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1989. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually from Washington headquarters and field offices of DOE, from the US Nuclear Regulatory Commission, from the US reactor manufacturers who are the principal nuclear contractors for foreign reactor locations, from US and foreign embassies, and from foreign governmental nuclear departments. Information is presented in five parts, each of which is categorized by primary function or purpose: civilian, production, military, export, and critical assembly facilities

  3. Nuclear safety in light water reactors severe accident phenomenology

    CERN Document Server

    Sehgal, Bal Raj

    2011-01-01

    This vital reference is the only one-stop resource on how to assess, prevent, and manage severe nuclear accidents in the light water reactors (LWRs) that pose the most risk to the public. LWRs are the predominant nuclear reactor in use around the world today, and they will continue to be the most frequently utilized in the near future. Therefore, accurate determination of the safety issues associated with such reactors is central to a consideration of the risks and benefits of nuclear power. This book emphasizes the prevention and management of severe accidents to teach nuclear professionals

  4. Social Chernobyl participants condition in Lithuania

    International Nuclear Information System (INIS)

    Full texts: At the moment in Lithuania live almost 6 600 Chernobyl participants (persons witch were in attendance Chernobyl nuclear power station emergency ravage liquidation works and executing another works in 30 kilometers zone). About 770 died and 170 went to other nations. Thievery other fixed illnesses coherence with being in 30 kilometers zone. According 26 October, 1990 Republic of Lithuania government's resolution No. 325 intended that Chernobyl participants credit accomplishes Ministry of Social care but until now in the Republic there is not undivided database, consequently we use different institution's and social investigations information which is not circumstantial. Chernobyl participants social condition and medicine service control certificates, government's resolutions and Ministry of health care and work and Ministry's of health care requisitions. There is not a law which guarantees Chernobyl participants social rights. Supposedly that for in Lithuania there is not the logistics which could vouch medical facilities provision for Chernobyl participants. Until 2005 sanatorium treating of Chernobyl participants was pursuance through invalids till but this treatment was not available to everyone Chernobyl participant for two reasons: 1 - Vicinities doctors and GPs not all the time contemprorize illnesses with being in The nuclear power station of the Chernobyl zone. 2 - Invalids till was not fixing the number of the permissions to the sanatoriums for the Chernobyl participants. Since 13 September, 2005 by Republic of Lithuania government's resolution No. 998 municipal governments budget bankrolls once a year may offset eighteen-days sanatorium treatment for persons which were liquidating The nuclear power-station of the Chernobyl emergency ravage but Chernobyl participants should give Specialists committee inference. Another problem social security. Chernobyl participant's requirement supply if they ill or died according Government's 18 February

  5. First international workshop on severe accidents and their consequences. [Chernobyl Accident

    Energy Technology Data Exchange (ETDEWEB)

    1989-07-01

    An international workshop on past severe nuclear accidents and their consequences was held in Dagomys region of Sochi, USSR on October 30--November 3, 1989. The plan of this meeting was approved by the USSR Academy of Sciences and by the USSR State Committee of the Utilization of Atomic Energy. The meeting was held under the umbrella of the ANS-SNS agreement of cooperation. Topics covered include analysis of the Chernobyl accident, safety measures for RBMK type reactors and consequences of the Chernobyl accident including analysis of the ecological, genetic and psycho-social factors. Separate reports are processed separately for the data bases. (CBS)

  6. Nuclear Energy Enabling Technologies (NEET) Reactor Materials: News for the Reactor Materials Crosscut, May 2016

    Energy Technology Data Exchange (ETDEWEB)

    Maloy, Stuart Andrew [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Science in Radiation and Dynamics Extremes

    2016-09-26

    In this newsletter for Nuclear Energy Enabling Technologies (NEET) Reactor Materials, pages 1-3 cover highlights from the DOE-NE (Nuclear Energy) programs, pages 4-6 cover determining the stress-strain response of ion-irradiated metallic materials via spherical nanoindentation, and pages 7-8 cover theoretical approaches to understanding long-term materials behavior in light water reactors.

  7. Sustainable and safe nuclear fission energy technology and safety of fast and thermal nuclear reactors

    CERN Document Server

    Kessler, Günter

    2012-01-01

    Unlike existing books of nuclear reactor physics, nuclear engineering and nuclear chemical engineering this book covers a complete description and evaluation of nuclear fission power generation. It covers the whole nuclear fuel cycle, from the extraction of natural uranium from ore mines, uranium conversion and enrichment up to the fabrication of fuel elements for the cores of various types of fission reactors. This is followed by the description of the different fuel cycle options and the final storage in nuclear waste repositories. In addition the release of radioactivity under normal and possible accidental conditions is given for all parts of the nuclear fuel cycle and especially for the different fission reactor types.

  8. Study of a cohort of Latvian workers having participated to the decontamination of the nuclear site of Chernobyl; Etude d`une cohorte de travailleurs lettons ayant participe a la decontamination du site nucleaire de Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Viel, J.F. [Faculte de Medecine de Besancon, 25 (France)

    1999-11-01

    In the consequences attributable to the accident at the Chernobyl nuclear power plant, it is debated whether post-disaster psycho-pathology is related to the perception of the level of contamination or the level of contamination itself. To address this issue, the authors have assessed the association of various exposure mental and psychosomatic distress, on a sample of 1,1412 Latvian liquidators drawn from the State Latvian Chernobyl clean-up workers registry. The outcome considered was a mixed mental/psychosomatic disorder occurring during the time period 1986-1995. Comparisons between subgroups of the cohort, classified according to exposure type or level, were based on the proportional hazards model. Length of work ({>=} 28 days) in a 10 km radius from the reactor (relative risk (RR) = 1.39, 95 percent confidence interval (CI) 1.14-1.70), work (> 1 time) on the damaged reactor roof (RR 1.46, 95 percent CI 1.02-2.09), forest work (RR 1.41,95 percent CI 1.19-1.68), and fresh fruits consumption ({>=} 1 time/day) (RR 1.72,95 percent CI 1.12-2.65) are risk factors for mixed mental/ psychosomatic disorder. Construction of the sarcophagus (RR 1.82, 95 percent CI 0.89-3.72), is also associated with this outcome, although non significantly. These findings confirm that some exposure variables represent risk factors for mental disorders and suggest some radiation-induced consequences although surely overweight by stress-related effects. (author)

  9. Innovative Nuclear Reactors: The future of nuclear reactor technology towards sustainable development

    International Nuclear Information System (INIS)

    Between a third and a quarter of human population does not have access to electricity, relying on burning wood as its only energy source. On the other hand, the developed countries, which consume most of the energy generated in the world, have an energy matrix based on the use of fossil sources. Such an energy matrix, if life unviable. Thus, promoting the development of third world countries, seeking equity and a better wealth distribution, is a challenge that impacts the survival of mankind. A particularly concerning issue is the increase of green house emissions (GH G) resulting from burning fossil fuels and the climatic consequences of such emissions. According to the intergovernmental Panel on Climate Change (IPCC), through is most evidences that anthropogenic causes, and in particular Co2 emissions, are among the main driving forces of global warming. Studies such as those of IPCC indicate that nuclear energy will have an important role as a key mitigation technology for containing Co2 emissions in the next decades. Nonetheless, the effective contribution of nuclear energy will depend on various factors related to economics, safety and security, public acceptance and sustain ability. There are two important initiatives regarding the discussions on the future of nuclear reactor technology. One of those is co-ordinated by the International Atomic Energy Agency (IAEA) and is known as International Project on Innovative Nuclear Reactor and fuel cycles (INPRO). The other is lead by the Department of Energy of the United States and is known as Generation IV (GIF). Indeed, the challenge facing the development of innovative nuclear reactors is, through comprehensive R§§D programs, to establish technological breakthroughs that overcome seemingly contradictory objectives of economy, safety and security, public acceptance and sustain ability

  10. Wildlife in Chernobyl forests

    International Nuclear Information System (INIS)

    The article is a review of a book addressed Wormwood Forest: a natural history of Chernobyl which describes life in Europe's largest wildlife sanctuary in the region surrounding the Chernobyl station. Since the accident, the area has largely been a safe haven from hunters and farmers, allowing the wildlife to live in an undisturbed environment. Against this backdrop, the book describes in detail, a highly controversial programme that released an endangered species of horse into the zone. Lack of funding for such programmes makes it nearly impossible to administer them. The book blends reportage, popular science and encounters with the zone's few residents. The result is an account of a remarkable land, its people and animals seen through the eyes of the locals, the author and the zoologists, botanists and radiologists who travelled with her around the zone. The radiation is the book's ever-present protagonist, as the author describes in detail how it works itself through the entire food chain and environment. Along the author's journey through the affected regions of Belarus and Ukraine she debunks several myths surrounding Chernobyl and the nuclear industry in general. In fact, while there have been a small number of cases of mutations observed in some species, these are not as dramatic as the Chernobyl mythology.

  11. Developing countries curtail nuclear power

    International Nuclear Information System (INIS)

    The nuclear power programmes in developing countries, following the accident at the Chernobyl power plant are summarized. Many of these have abandoned plans for nuclear power (eg Gabon), mothballed existing reactors (eg Philippines) or deferred decisions on a reactor programme (eg Egypt, Taiwan, Libya). Economic and political pressures are usually the underlying reasons, but the Chernobyl incident has proved a useful excuse. Other countries (Nigeria, Korea, India, Pakistan) have not let the accident change their nuclear policy. In China, Israel and Turkey the debate about nuclear power has been sharpened by the accident. Although Chernobyl has hastened decisions on nuclear power in some countries it has not affected the long-term policies of developing countries. (UK)

  12. A brief history of design studies on innovative nuclear reactors

    Science.gov (United States)

    Sekimoto, Hiroshi

    2014-09-01

    In a short period after the success of CP1, many types of nuclear reactors were proposed and investigated. However, soon only a small number of reactors were selected for practical use. Around 1970, only LWRs with small number of CANDUs were operated in the western world, and FBRs were under development. It was about the time when Apollo moon landing was accomplished. However, at the same time, the future of human being was widely considered pessimistic and Limits to Growth was published. In the end of 1970's the TMI accident occurred and many nuclear reactor contracts were cancelled in USA and any more contracts had not been concluded until recent years. From the reflection of this accident, many Inherent Safe Reactors (ISRs) were proposed, though none of them were constructed. A common idea of ISRs is smallness of their size. Tokyo Institute of Technology (TokyoTech) held a symposium on small reactors, SR/TIT, in 1991, where many types of small ISRs were presented. Recently small reactors attract interest again. The most ideas employed in these reactors were the same discussed in SR/TIT. In 1980's the radioactive wastes from fuel cycle became a severe problem around the world. In TokyoTech, this issue was discussed mainly from the viewpoint of nuclear transmutations. The neutron economy became inevitable for these innovative nuclear reactors especially small long-life reactors and transmutation reactors.

  13. A brief history of design studies on innovative nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Sekimoto, Hiroshi, E-mail: hsekimot@gmail.com [Emeritus Professor, Tokyo Institute of Technology (Japan)

    2014-09-30

    In a short period after the success of CP1, many types of nuclear reactors were proposed and investigated. However, soon only a small number of reactors were selected for practical use. Around 1970, only LWRs with small number of CANDUs were operated in the western world, and FBRs were under development. It was about the time when Apollo moon landing was accomplished. However, at the same time, the future of human being was widely considered pessimistic and Limits to Growth was published. In the end of 1970’s the TMI accident occurred and many nuclear reactor contracts were cancelled in USA and any more contracts had not been concluded until recent years. From the reflection of this accident, many Inherent Safe Reactors (ISRs) were proposed, though none of them were constructed. A common idea of ISRs is smallness of their size. Tokyo Institute of Technology (TokyoTech) held a symposium on small reactors, SR/TIT, in 1991, where many types of small ISRs were presented. Recently small reactors attract interest again. The most ideas employed in these reactors were the same discussed in SR/TIT. In 1980’s the radioactive wastes from fuel cycle became a severe problem around the world. In TokyoTech, this issue was discussed mainly from the viewpoint of nuclear transmutations. The neutron economy became inevitable for these innovative nuclear reactors especially small long-life reactors and transmutation reactors.

  14. Nuclear Reactor RA Safety Report, Vol. 4, Reactor

    International Nuclear Information System (INIS)

    RA research reactor is thermal heavy water moderated and cooled reactor. Metal uranium 2% enriched fuel elements were used at the beginning of its operation. Since 1976, 80% enriched uranium oxide dispersed in aluminium fuel elements were gradually introduced into the core and are the only ones presently used. Reactor core is cylindrical, having diameter 40 cm and 123 cm high. Reaktor core is made up of 82 fuel elements in aluminium channels, lattice is square, lattice pitch 13 cm. Reactor vessel is cylindrical made of 8 mm thick aluminium, inside diameter 140 cm and 5.5 m high surrounded with neutron reflector and biological shield. There is no containment, the reactor building is playing the shielding role. Three pumps enable circulation of heavy water in the primary cooling circuit. Degradation of heavy water is prevented by helium cover gas. Control rods with cadmium regulate the reactor operation. There are eleven absorption rods, seven are used for long term reactivity compensation, two for automatic power regulation and two for safety shutdown. Total anti reactivity of the rods amounts to 24%. RA reactor is equipped with a number of experimental channels, 45 vertical (9 in the core), 34 in the graphite reflector and two in the water biological shield; and six horizontal channels regularly distributed in the core. This volume include detailed description of systems and components of the RA reactor, reactor core parameters, thermal hydraulics of the core, fuel elements, fuel elements handling equipment, fuel management, and experimental devices

  15. Proposal of Space Reactor for Nuclear Electric Propulsion System

    Science.gov (United States)

    Nagata, Hidetaka; Nishiyama, Takaaki; Nakashima, Hideki

    Currently, the solar battery, the chemical cell, and the RI battery are used for the energy source in space. However, it is difficult for them to satisfy requirements for deep space explorations. Therefore, other electric power sources which can stably produce high electric energy output, regardless of distance from the sun, are necessary to execute such missions. Then, we here propose small nuclear reactors as power sources for deep space exploration, and consider a conceptual design of a small nuclear reactor for Nuclear Electric Propulsion System. It is found from nuclear analyses that the Gas-Cooled reactor could not meet the design requirement imposed on the core mass. On the other hand, a light water reactor is found to be a promising alternative to the Gas-Cooled reactor.

  16. Nuclear reactors built, being built, or planned, 1991

    International Nuclear Information System (INIS)

    This document contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1991. The book is divided into three major sections: Section 1 consists of a reactor locator map and reactor tables; Section 2 includes nuclear reactors that are operating, being built, or planned; and Section 3 includes reactors that have been shut down permanently or dismantled. Sections 2 and 3 contain the following classification of reactors: Civilian, Production, Military, Export, and Critical Assembly. Export reactor refers to a reactor for which the principal nuclear contractor is an American company -- working either independently or in cooperation with a foreign company (Part 4, in each section). Critical assembly refers to an assembly of fuel and assembly of fuel and moderator that requires an external source of neutrons to initiate and maintain fission. A critical assembly is used for experimental measurements (Part 5)

  17. Nuclear reactors built, being built, or planned, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, B.

    1992-07-01

    This document contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1991. The book is divided into three major sections: Section 1 consists of a reactor locator map and reactor tables; Section 2 includes nuclear reactors that are operating, being built, or planned; and Section 3 includes reactors that have been shut down permanently or dismantled. Sections 2 and 3 contain the following classification of reactors: Civilian, Production, Military, Export, and Critical Assembly. Export reactor refers to a reactor for which the principal nuclear contractor is an American company -- working either independently or in cooperation with a foreign company (Part 4, in each section). Critical assembly refers to an assembly of fuel and assembly of fuel and moderator that requires an external source of neutrons to initiate and maintain fission. A critical assembly is used for experimental measurements (Part 5).

  18. Accidents - Chernobyl accident

    International Nuclear Information System (INIS)

    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.)

  19. The characterization and risk assessment of the `Red Forest` radioactive waste burial site at Chernobyl Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Bungai, D.A.; Skalskij, A.S.; Dzhepo, S.P. [AN Ukrainskoj SSR, Kiev (Ukraine). Inst. Geologicheskikh Nauk; Waters, R.D. [Sandia National Labs., Albuquerque, NM (United States)

    1996-06-01

    The `Red Forest` radioactive waste burials created during emergency clean-up activities at Chernobyl Nuclear Power Plant represent a serious source of radioactive contamination of the local ground water system with 9OSr concentration in ground water exceeding the drinking water standard by 3-4 orders of magnitude. In this paper we present results of our hydrogeological and radiological `Red Forest` site characterization studies, which allow us to estimate 9OSr subsurface migration parameters. We use then these parameters to assess long terrain radionuclide transport to groundwater and surface water, and to analyze associated health risks. Our analyses indicate that 9OSr transport via ground water pathway from `Red Forest` burials to the adjacent Pripyat River is relatively insignificant due to slow release of 9OSr from the waste burials (less than 1% of inventory per year) and due to long enough ground water residence time in the subsurface, which allows substantial decay of the radioactive contaminant. Tins result and our previous analyses indicate, that though conditions of radioactive waste storage in burials do not satisfy Ukrainian regulation on radiation protection, health risks caused by radionuclide migration to ground water from `Red Forest` burials do not justify application of expensive countermeasures.

  20. Radioactivity monitoring and import regulation of the contaminated foodstuffs in Japan following the Chernobyl nuclear power plant accident

    Energy Technology Data Exchange (ETDEWEB)

    Izumo, Yoshiro [Institute of Public Health, Tokyo (Japan)

    1997-03-01

    Radioactivity monitoring and import regulation of the contaminated foodstuffs executed by Minstry of Health and Welfare following the Chernobyl nuclear plant accident were reviewed as follows; (1) background of socio-psychological effects and environmental radioactivity leading to the regulation (to may 3, 1986); (2) intial intervention for imported foodstuffs in Japan (may 8, `86), and (3) in european countries (to may 31, `86), immediately after the Accident, respectively; (4) determination of the interim driven intervention level for radionuclides in imported foodstuffs (({sup 134}Cs + {sup 137}Cs): 370 Bq/Kg) and activation of the monitoring, (5) outline of the monitoring with elapsed time, number of foodstuffs monitored, number of foodstuffs exceeded radioactivity of the intervention level and re-exported; (6) guideline in international trade of radioactive contaminated foodstuffs adopted by CODEX Alimentarius Commission (FAO/WHO) and the intervention level recommended by ICRP following the Accident; (7) discussion for problems and scopes in future based on the results of monitoring. As the results, a number of imported foodstuffs (about 75,000 samples at present) has been monitored, 55 samples exceeding the interim intervention level were re-exported to each export`s country, and socio-psychological doubts for radioactive contamination of imported foodstuffs have been dispersed. In addition, problems for several factors based on calculation of the interim intervention level, radioactivity level of foodstuffs exceeding about 50 Bq/Kg as radiocesiums and necessity of monitoring for the other radionuclides in foods except radiocesiums were also discussed. (author)

  1. Dynamics of 137Cs in the forests of the 30-km zone around the Chernobyl nuclear power plant

    International Nuclear Information System (INIS)

    Dynamics of the 137Cs content in the components of the forests in the 30-km zone around the Chernobyl nuclear power plant (NPP) in 1986–1994 are associated mainly with such factors as the size of radioactive particles in the fallout, ecosystem humidification and soil type, tree age. The influence of particle size was especially noticable between 1986–1987 and was displayed by low biological availability of radionuclides in the near part of the zone (within the 10-km radius circle around the NPP) in comparison with more distant regions (within the 30-km radius circle). Later, the expression of this influence decreased and transfer factor (the ratio of 137Cs content in overground phytomass to the soil contamination density) became approximately the same for all plots with similar ecological and fallout characteristics. Humidity of landscape and soil type determined the velocity of radionuclide vertical migration in the soil and 137Cs biological availability. These parameters were maximum for the hydromorphic soils of wet landscapes enriched in organic substance and poor clayey minerals. Differences of 137Cs accumulation in overground phytomass of trees caused by tree age are displayed in the higher 137Cs concentration in structural parts of young trees as compared with old ones

  2. Dynamics of 137Cs in the forests of the 30-km zone around the Chernobyl nuclear power plant

    International Nuclear Information System (INIS)

    Dynamics of the 137Cs content in the components of the forests in the 30-km zone around the Chernobyl nuclear power plant (NPP) in 1986-1994 are associated mainly with such factors as the size of radioactive particles in the fallout, ecosystem humidification and soil type, tree age. The influence of particle size was especially noticeable between 1986-1987 and was displayed by low biological availability of radionuclides in the near part of the zone (within the 10-km radius circle around the NPP) in comparison with more distant regions (within the 30-km radius circle). Later, the expression of this influence decreased and transfer factor (the ratio of 137Cs content in overground phytomass to the soil contamination density) became approximately the same for all plots with similar ecological and fallout characteristics. Humidity of landscape and soil type determined the velocity of radionuclide vertical migration in the soil and 137Cs biological availability. These parameters were maximum for the hydromorphic soils of wet landscapes enriched in organic substance and poor clayey minerals. Differences of 137Cs accumulation in overground phytomass of trees caused by tree age are displayed in the higher 137Cs concentration in structural parts of young trees as compared with old ones

  3. Post-Chernobyl emergency planning

    International Nuclear Information System (INIS)

    This report is the result of a study ordered by the Swedish Nuclear Power Inspectorate and the National Swedish Institute of Radiation Protection to evaluate the measurements taken in Sweden in response to the Chernobyl accident. The enquiry was also given the task of suggesting improvements of the nuclear accidents emergency planning and other activities relevant to nuclear accidents. Detailed accounts are given of the course of events in Sweden at the Chernobyl accident and the steps taken by central or local authorities are discussed. Several alterations of the emergency planning are proposed and a better coordination of the affected organizations is suggested. (L.E.)

  4. A study on future nuclear reactor technology and development strategy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. Y.; Kim, S. H.; Sohn, D. S.; Suk, S. D.; Zee, S. K.; Yang, M. H.; Kim, H. J.; Park, W. S

    2000-12-01

    Development of nuclear reactor and fuel cycle technology for future is essential to meet the current issues such as enhancement of nuclear power reactor safety, economically competitive with gas turbine power generation, less production of radioactive waste, proliferation resistant fuel cycle, and public acceptance in consideration of lack of energy resources in the nuclear countries worldwide as well as in Korea. This report deals with as follows, 1) Review the world energy demand and supply perspective and analyse nature of energy and sustainable development to set-up nuclear policy in Korea 2) Recaptitulate the current long term nuclear R and D activities 3) Review nuclear R and D activities and programs of USA, Japan, France, Russia, international organizations such as IAEA, OECD/NEA 4) Recommend development directions of nuclear reactors and fuels.

  5. Theory of neutron slowing down in nuclear reactors

    CERN Document Server

    Ferziger, Joel H; Dunworth, J V

    2013-01-01

    The Theory of Neutron Slowing Down in Nuclear Reactors focuses on one facet of nuclear reactor design: the slowing down (or moderation) of neutrons from the high energies with which they are born in fission to the energies at which they are ultimately absorbed. In conjunction with the study of neutron moderation, calculations of reactor criticality are presented. A mathematical description of the slowing-down process is given, with particular emphasis on the problems encountered in the design of thermal reactors. This volume is comprised of four chapters and begins by considering the problems

  6. The current status of nuclear research reactor in Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Sittichai, C.; Kanyukt, R.; Pongpat, P. [Office of Atomic Energy for Peace, Bangkok (Thailand)

    1998-10-01

    Since 1962, the Thai Research Reactor has been serving for various kinds of activities i.e. the production of radioisotopes for medical uses and research and development on nuclear science and technology, for more than three decades. The existing reactor site should be abandoned and relocated to the new suitable site, according to Thai cabinet`s resolution on the 27 December 1989. The decommissioning project for the present reactor as well as the establishment of new nuclear research center were planned. This paper discussed the OAEP concept for the decommissioning programme and the general description of the new research reactor and some related information were also reported. (author)

  7. Reactor safety - an international task

    International Nuclear Information System (INIS)

    The dimensions and the significance of the task of ensuring reactor safety can be defined on the basis of experiences gained from Harrisburg and Chernobyl. The countries that use nuclear energy are tied together to a community by virtue of the risk they share. Therefore the GRS is working in close cooperation with the EC, OECD, IAEO and COMECON. This results in safety examinations of the Greifswald reactor, safety analyses of nuclear reactors in Germany, France and the USA and also considerations on the safety demands to be placed on new reactor concepts. (DG)

  8. Reactors. Nuclear propulsion ships; Reacteurs. Navires a propulsion nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Fribourg, Ch. [Technicatome, Centre d' Etudes Nucleaires de Saclay, 91 - Gif sur Yvette (France)

    2001-07-01

    This article has for object the development of nuclear-powered ships and the conception of the nuclear-powered ship. The technology of the naval propulsion P.W.R. type reactor is described in the article B.N.3 141 'Nuclear Boilers ships'. (N.C.)

  9. Safety review and assessment and inspection on research reactors, experimental reactors, nuclear heating reactors and critical facilities

    International Nuclear Information System (INIS)

    More operational events were occurred at various research reactors in 1995. The NNSA and its regional offices conducted careful investigation and strict regulation. In order to analyze comprehensively the safety situation of inservice research reactors and find same countermeasures the NNSA convened a meeting of the safety regulation on research reactors and a meeting for change experience of the safety regulation on research reactors that were participated in by the operating organizations in 1995. A lot of work has been done in the respects of propagation of regulations on nuclear safety, education of nuclear safety culture, the investigation and treatment of operational events, the reexamine of operation documents, the implementation of rectifying items on nuclear safety, the daily inspection and routine inspection on nuclear safety and the studying on the extending service life of research reactors etc

  10. Research means to back the development of nuclear reactors

    International Nuclear Information System (INIS)

    After 50 year long feedback experience on nuclear reactor operations it is legitimate to wonder whether experimental facilities used to support nuclear power programs are still necessary. The various participants of this conference said yes for mainly 4 reasons: -) to validate the extension of the service life of a reactor without putting at risk its high safety standard, -) to give the reactor more flexibility to cope with the power demand, -) to confront the results given by computerized simulations with experimental data, and -) to qualify the nuclear systems of tomorrow. (A.C.)

  11. Consequences of the Chernobyl accident

    International Nuclear Information System (INIS)

    A collection of three papers about the fallout in Austria from the 1986 Chernobyl reactor accident is given: 1. An overview of the research projects in Austria; 2. On the transfer into and uptake by crops and animal fodder; 3. On the reduction of cesium concentration in food. 18 tabs., 21 figs., 69 refs

  12. Project Chernobyl

    International Nuclear Information System (INIS)

    The aim of the follow-up after the Chernobyl fallout is to obtain the best possible information about the environmental and dose commitment consequences in Sweden. The essential part of the work by the institute to improve the state of readiness is described. (G.B.)

  13. Research nuclear reactor RA - Annual Report 2000

    International Nuclear Information System (INIS)

    Activities related to revitalisation of the RA reactor started in 1986 were fulfilled except the exchange of the complete reactor instrumentation. Since 1992, due to economic and political reasons, RA reactor is in a difficult situation. The old RA reactor instrumentation was dismantled. Decision about the future status of the reactor should be made because the aging of all the components is becoming dramatic. Control and maintenance of the reactor components was done regularly and efficiently. The most important activity and investment in 1998 was improvement of conditions for spent fuel storage in the existing pools at the RA reactor. Russian company ENTEK and IAEA are involved in this activity which was initiated 1997. Fuel inspection by the IAEA safeguards inspectors was done on a monthly basis. Research reactor RA Annual report for year 2000 is divided into two main parts to cover: (1) operation and maintenance and (2) activities related to radiation protection

  14. Research nuclear reactor RA - Annual Report 1998

    International Nuclear Information System (INIS)

    Activities related to revitalisation of the RA reactor started in 1986 were fulfilled except the exchange of the complete reactor instrumentation. Since 1992, due to economic and political reasons, RA reactor is in a difficult situation. The old RA reactor instrumentation was dismantled. Decision about the future status of the reactor should be made because the aging of all the components is becoming dramatic. Control and maintenance of the reactor components was done regularly and efficiently. The most important activity and investment in 1998 was improvement of conditions for spent fuel storage in the existing pools at the RA reactor. Russian company ENTEK and IAEA are involved in this activity which was initiated 1997. Fuel inspection by the IAEA safeguards inspectors was done on a monthly basis. Research reactor RA Annual report for year 1998 is divided into two main parts to cover: (1) operation and maintenance and (2) activities related to radiation protection

  15. Chernobyl; Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This report relates the Chernobylsk accident, why following a succession of technical malfunctions and human errors, reactor no. 4 of the Chernobylsk nuclear power plant explodes on April 26. 1986. Radioactive dust, aerosols and gases (including caesium and iodine) are ejected into atmosphere. The regions worst hit are in the immediate vicinity of the plant, but deposits are very uneven, producing a leopard spot type of pattern. Propelled by easterly winds, the radioactive cloud disperses increasingly, scattering deposits over the whole of Europe. At the beginning of May, the cloud arrives in France. the eastern portion of the country is most strongly affected. Ground, water and agriculture are contaminated by caesium deposits in Belarus, Ukraine and Russian Federation. About the contamination in France, ground contamination is slight, fourteen years later, however, it is still detectable. Relative to the impact on health in the vicinity of Chernobylsk plant, it is hard to assess this impact. Among children in Southern Belarus, the number of thyroid cancers has risen one hundred-fold. In France, the doses delivered represents generally less than 1% of the average annual dose from radioactivity of natural origin. But some of the doses received were higher. Today, the protective sarcophagus covering the damaged reactor is fragile. Reactor no.3, still in operation, continues to pose a risk but the shutdown is provided for december 2000. (N.C.)

  16. SUBSTANTIAL AND STRUCTURAL COMPONENTS OF THE MENTAL STATUS OF THE PERSONS WHO HAVE RECEIVED SMALL DOSES OF RADIATION DURING LIGUIDATION OF THE ACCIDENT AT THE CHERNOBYL NUCLEAR POWER PLANT

    Directory of Open Access Journals (Sweden)

    О. V. Baranova

    2012-01-01

    Full Text Available In the article the peculiarities of ideas about the catastrophe at the Chernobyl nuclear power plant disaster at the persons who have suffered from radiation during liquidation of the accident’s consequences. View of the accident was considered as a key element of a person’s mind, in particular the adaptive. There were 30 persons, who took part in the research – participants of Chernobyl disaster’s liquidation, veterans of division of an extra risk. The subjective assessment of mental health at persons who survived in Chernobyl disaster was defined; personal properties of victims were revealed; interrelations between personal properties and subjective assessment of mental health were established. It is possible to assume that in process of moving away from the moment of the accident the content of view of Chernobyl disaster shows concentration of the person on experience of mental health and the personal potential.

  17. Nuclear reactors built, being built, or planned 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-08-01

    This publication contains unclassified information about facilities, built, being built, or planned in the United States for domestic use or export as of December 31, 1996. The Office of Scientific and Technical Information, U.S. Department of Energy, gathers this information annually from Washington headquarters, and field offices of DOE; from the U.S. Nuclear Regulatory Commission (NRC); from the U. S. reactor manufacturers who are the principal nuclear contractors for foreign reactor locations; from U.S. and foreign embassies; and from foreign governmental nuclear departments. The book consists of three divisions, as follows: (1) a commercial reactor locator map and tables of the characteristic and statistical data that follow; a table of abbreviations; (2) tables of data for reactors operating, being built, or planned; and (3) tables of data for reactors that have been shut down permanently or dismantled.

  18. Nuclear reactors built, being built, or planned: 1996

    International Nuclear Information System (INIS)

    This publication contains unclassified information about facilities, built, being built, or planned in the United States for domestic use or export as of December 31, 1996. The Office of Scientific and Technical Information, U.S. Department of Energy, gathers this information annually from Washington headquarters, and field offices of DOE; from the U.S. Nuclear Regulatory Commission (NRC); from the U. S. reactor manufacturers who are the principal nuclear contractors for foreign reactor locations; from U.S. and foreign embassies; and from foreign governmental nuclear departments. The book consists of three divisions, as follows: (1) a commercial reactor locator map and tables of the characteristic and statistical data that follow; a table of abbreviations; (2) tables of data for reactors operating, being built, or planned; and (3) tables of data for reactors that have been shut down permanently or dismantled

  19. Nuclear reactor core modelling in multifunctional simulators

    Energy Technology Data Exchange (ETDEWEB)

    Puska, E.K. [VTT Energy, Nuclear Energy, Espoo (Finland)

    1999-06-01

    The thesis concentrates on the development of nuclear reactor core models for the APROS multifunctional simulation environment and the use of the core models in various kinds of applications. The work was started in 1986 as a part of the development of the entire APROS simulation system. The aim was to create core models that would serve in a reliable manner in an interactive, modular and multifunctional simulator/plant analyser environment. One-dimensional and three-dimensional core neutronics models have been developed. Both models have two energy groups and six delayed neutron groups. The three-dimensional finite difference type core model is able to describe both BWR- and PWR-type cores with quadratic fuel assemblies and VVER-type cores with hexagonal fuel assemblies. The one- and three-dimensional core neutronics models can be connected with the homogeneous, the five-equation or the six-equation thermal hydraulic models of APROS. The key feature of APROS is that the same physical models can be used in various applications. The nuclear reactor core models of APROS have been built in such a manner that the same models can be used in simulator and plant analyser applications, as well as in safety analysis. In the APROS environment the user can select the number of flow channels in the three-dimensional reactor core and either the homogeneous, the five- or the six-equation thermal hydraulic model for these channels. The thermal hydraulic model and the number of flow channels have a decisive effect on the calculation time of the three-dimensional core model and thus, at present, these particular selections make the major difference between a safety analysis core model and a training simulator core model. The emphasis on this thesis is on the three-dimensional core model and its capability to analyse symmetric and asymmetric events in the core. The factors affecting the calculation times of various three-dimensional BWR, PWR and WWER-type APROS core models have been

  20. Neutron spectrometer for fast nuclear reactors

    CERN Document Server

    Osipenko, M; Ricco, G; Caiffi, B; Pompili, F; Pillon, M; Angelone, M; Verona-Rinati, G; Cardarelli, R; Mila, G; Argiro, S

    2015-01-01

    In this paper we describe the development and first tests of a neutron spectrometer designed for high flux environments, such as the ones found in fast nuclear reactors. The spectrometer is based on the conversion of neutrons impinging on $^6$Li into $\\alpha$ and $t$ whose total energy comprises the initial neutron energy and the reaction $Q$-value. The $^6$LiF layer is sandwiched between two CVD diamond detectors, which measure the two reaction products in coincidence. The spectrometer was calibrated at two neutron energies in well known thermal and 3 MeV neutron fluxes. The measured neutron detection efficiency varies from 4.2$\\times 10^{-4}$ to 3.5$\\times 10^{-8}$ for thermal and 3 MeV neutrons, respectively. These values are in agreement with Geant4 simulations and close to simple estimates based on the knowledge of the $^6$Li(n,$\\alpha$)$t$ cross section. The energy resolution of the spectrometer was found to be better than 100 keV when using 5 m cables between the detector and the preamplifiers.

  1. Development of nuclear fuel for integrated reactor

    Energy Technology Data Exchange (ETDEWEB)

    Song, Kee Nam; Kim, H. K.; Kang, H. S.; Yoon, K. H.; Chun, T. H.; In, W. K.; Oh, D. S.; Kim, D. W.; Woo, Y. M

    1999-04-01

    The spacer grid assembly which provides both lateral and vertical support for the fuel rods and also provides a flow channel between the fuel rods to afford the heat transfer from the fuel pellet into the coolant in a reactor, is one of the major structural components of nuclear fuel for LWR. Therefore, the spacer grid assembly is a highly ranked component when the improvement of hardware is pursued for promoting fuel performance. Main objective of this project is to develop the inherent spacer grid assembly and to research relevant technologies on the spacer grid assembly. And, the UO{sub 2}-based SMART fuel is preliminarily designed for the 330MWt class SMART, which is planned to produce heat as well as electricity. Results from this project are listed as follows. 1. Three kinds of spacer grid candidates have been invented and applied for domestic and US patents. In addition, the demo SG(3x3 array) were fabricated, which the mechanical/structural test was carried out with. 2. The mechanical/structural technologies related to the spacer grid development are studied and relevant test requirements were established. 3. Preliminary design data of the UO{sub 2}-based SMART fuel have been produced. The structural characteristics of several components such as the top/bottom end piece and the holddown spring assembly were analysed by consulting the numerical method.

  2. Method for inspecting nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    A technique for disassembling a nuclear reactor fuel element without destroying the individual fuel pins and other structural components from which the element is assembled is described. A traveling bridge and trolley span a water-filled spent fuel storage pool and support a strongback. The strongback is under water and provides a working surface on which the spent fuel element is placed for inspection and for the manipulation that is associated with disassembly and assembly. To remove, in a non-destructive manner, the grids that hold the fuel pins in the proper relative positions within the element, bars are inserted through apertures in the grids with the aid of special tools. These bars are rotated to flex the adjacent grid walls and, in this way relax the physical engagement between protruding portions of the grid walls and the associated fuel pins. With the grid structure so flexed to relax the physical grip on the individual fuel pins, these pins can be withdrawn for inspection or replacement as necessary without imposing a need to destroy fuel element components

  3. Evaluation of radiation impacts of spent nuclear fuel storage (ISP-2) of Chernobyl NPP

    International Nuclear Information System (INIS)

    The estimation of radiation impacts during normal operation of dry spent fuel storage facility for ChNPP RBMK reactors, designed for long-term storage of spent fuel assemblies (SFA), which originated from the operation 1,2,and 3 units ChNPP was made. It is shown that the maximum concentration of radionuclides in the air near the ISF-2 well below allowable concentration for the population, and additional pollution is negligible in comparison with the existing one

  4. The awareness of the functional and near population with the relation to the research nuclear reactor IEA-R1

    Energy Technology Data Exchange (ETDEWEB)

    Vanni, Silvia R.; Martins, Maria da Penha S. [Centro Tecnologico da Marinha (CTMSP), SP (Brazil); Sabundjian, Gaiane, E-mail: gdjian@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    After the natural accident that hit Japan in the beginning of March of 2011, and that ended into an accident of great proportions in the nuclear installations of Fukushima, it has now the debate over the lack of information that the population in general has over the nuclear energy. The dissemination of information, about the operation and security of the nuclear reactors, has the purpose of softening the effect that the pessimistic atmosphere has over its using. This study was reinforced by the memories of serious consequences due to other nuclear accidents that have already happened (Chernobyl, Three-Mile and Hiroshima/Nagasaki event), bringing insecurity, fear and even revenge from part of the public. Over all, people are not sufficiently informed about the positives and negatives aspects of the nuclear energy. It is necessary the adoption of a clear and aware policy with the population, about the pacific use of nuclear energy. Today, the international and national organizations of control of nuclear energy, the International Atomic Energy Agency (IAEA) and the Comissao Nacional de Energia Nuclear (CNEN), have respectively, published information about this subject using a more professional way and of hard access for the public in general. This work has the goal of checking the level of information that the population of workers and individuals of the close public to the research nuclear reactor IEA-R1, located in the Institute of Nuclear Research (IPEN), University City, Sao Paulo, Brazil, has over it. The way used for this study, involved questionnaires with straight questions and of simple language over the subject, to people of all different social, economic and cultural classes, from 12 to 80 years old. From the results found after this work, it was verified the necessity to elaborate a project of awareness of information and clarification about the nuclear energy, using ways of communication that exist and that are easy for the public to understand. (author)

  5. Special Nuclear Material Control by the Power Reactor Operator

    International Nuclear Information System (INIS)

    A relatively new and extremely valuable fuel for electric power production, uranium, requires very careful inventory control from the time the reactor operator assumes financial responsibility for this material until, as partially expended fuel, it is transferred to another facility and the remaining part of its initial value is recovered. Most power reactor operators were operating fossil-fuelled power plants before the advent of nuclear power and have long since established rather complete and adequate controls for these fossil fuels. The reactor operator must have no less adequate controls for the special nuclear material used in his nuclear plant. Power reactor, operation is not an ancient science and during its relatively short history our engineers and scientists have been constantly improving plant designs and methods of operation to reduce costs and make our nuclear plants competitive with fossil-fuelled conventional plants. Nuclear material management must be as modern and efficient as is humanly possible to ensure that technological advances leading to reduced costs are not lost by poor handling of nuclear fuel and the records pertaining to fuel inventory. Nuclear material management requires the maintaining of complete and informative records by the power reactor operator. These records need not be complex to satisfy the criteria of completeness and adequacy. In fact, simplicity is extremely desirable. Despite the fact that nuclear fuel is new and completely different to our conventional fuels no mystery should be attached thereto. Nuclear material control as part of nuclear material management is not limited to simple inventory work but it is the basis for a great deal of other activity that is an inherent part of any power reactor operations such as irradiated fuel shipments, reprocessing of spent fuel, with its associated accounting for reclaimed fuel and material produced during reactor operation, and the establishing and maintaining of an adequate

  6. Integrated lid unit for a nuclear reactor of standard construction

    International Nuclear Information System (INIS)

    This is an integrated lid unit for a nuclear reactor of standard construction, where many components and sub-groups of the upper reactor structure are collected into one unit, which is lifted in one lifting operation from the reactor containment vessel. The integrated lid unit includes, in particular, the pressure vessel lid, a cooling jacket, the control rod drive mechanisms, a catch plate, a lifting device, a winch and a cable connection plate. (orig.)

  7. Hydrogen production by water dissociation from a nuclear reactor

    International Nuclear Information System (INIS)

    This memento presents the production of hydrogen by water decomposition, the energy needed for the electrolysis, the thermochemical cycles for a decomposition at low temperature and the possible nuclear reactors associated. (A.L.B.)

  8. Accelerators and nuclear reactors as tools in hot atom chemistry

    International Nuclear Information System (INIS)

    The characteristics of accelerators and of nuclear reactors - the latter to a lesser extent - are discussed in view of their present and future use in hot atom chemistry research and its applications. (author)

  9. Solid0Core Heat-Pipe Nuclear Batterly Type Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ehud Greenspan

    2008-09-30

    This project was devoted to a preliminary assessment of the feasibility of designing an Encapsulated Nuclear Heat Source (ENHS) reactor to have a solid core from which heat is removed by liquid-metal heat pipes (HP).

  10. Reactor/Brayton power systems for nuclear electric spacecraft

    International Nuclear Information System (INIS)

    Studies are currently underway to assess the technological feasibility of a nuclear-reactor-powered spacecraft propelled by electric thrusters. The purpose of this study was to provide comparative information on a closed cycle gas turbine power conversion system

  11. Plutonium Discharge Rates and Spent Nuclear Fuel Inventory Estimates for Nuclear Reactors Worldwide

    Energy Technology Data Exchange (ETDEWEB)

    Brian K. Castle; Shauna A. Hoiland; Richard A. Rankin; James W. Sterbentz

    2012-09-01

    This report presents a preliminary survey and analysis of the five primary types of commercial nuclear power reactors currently in use around the world. Plutonium mass discharge rates from the reactors’ spent fuel at reload are estimated based on a simple methodology that is able to use limited reactor burnup and operational characteristics collected from a variety of public domain sources. Selected commercial reactor operating and nuclear core characteristics are also given for each reactor type. In addition to the worldwide commercial reactors survey, a materials test reactor survey was conducted to identify reactors of this type with a significant core power rating. Over 100 material or research reactors with a core power rating >1 MW fall into this category. Fuel characteristics and spent fuel inventories for these material test reactors are also provided herein.

  12. Monstrosities - an outcome of Chernobyl?

    International Nuclear Information System (INIS)

    In the western parts of Turkey, which have been particularly hard hidden by the radioactive fallout from the Chernobyl reactor accident, an extremely high number of malformations in newborns have been recorded. There is reason to attribute this to the high radioactivity level measured in this region after the accident. But most radiation experts refuse to accept any connection between the miscarriages or malformation and the reactor accident. (orig./HP)

  13. Neutron noise analysis techniques in nuclear power reactors

    International Nuclear Information System (INIS)

    The main techniques used in neutron noise analysis of BWR and PWR nuclear reactors are reviewed. Several applications such as control of vibrations in both reactor types, determination of two phase flow parameters in BWR and stability control in BWR are discussed with some detail. The paper contains many experimental results obtained by the main author of this paper. (author)

  14. Nuclear reactors built, being built, or planned, 1994

    International Nuclear Information System (INIS)

    This document contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1994. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually from Washington headquarters and field offices of DOE; from the US Nuclear Regulatory Commission (NRC); from the US reactor manufacturers who are the principal nuclear contractors for foreign reactor locations; from US and foreign embassies; and from foreign governmental nuclear departments. The book consists of three divisions, as follows: a commercial reactor locator map and tables of the characteristic and statistical data that follow; a table of abbreviations; tables of data for reactors operating, being built, or planned; and tables of data for reactors that have been shut down permanently or dismantled. The reactors are subdivided into the following parts: Civilian, Production, Military, Export, and Critical Assembly. Export reactor refers to a reactor for which the principal nuclear contractor is a US company -- working either independently or in cooperation with a foreign company (Part 4). Critical assembly refers to an assembly of fuel and moderator that requires an external source of neutrons to initiate and maintain fission. A critical assembly is used for experimental measurements (Part 5)

  15. Nuclear reactors built, being built, or planned, 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    This document contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1994. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually from Washington headquarters and field offices of DOE; from the US Nuclear Regulatory Commission (NRC); from the US reactor manufacturers who are the principal nuclear contractors for foreign reactor locations; from US and foreign embassies; and from foreign governmental nuclear departments. The book consists of three divisions, as follows: a commercial reactor locator map and tables of the characteristic and statistical data that follow; a table of abbreviations; tables of data for reactors operating, being built, or planned; and tables of data for reactors that have been shut down permanently or dismantled. The reactors are subdivided into the following parts: Civilian, Production, Military, Export, and Critical Assembly. Export reactor refers to a reactor for which the principal nuclear contractor is a US company -- working either independently or in cooperation with a foreign company (Part 4). Critical assembly refers to an assembly of fuel and moderator that requires an external source of neutrons to initiate and maintain fission. A critical assembly is used for experimental measurements (Part 5).

  16. Nuclear reactors built, being built, or planned: 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    This report contains unclassified information about facilities built, being built, or planned in the US for domestic use or export as of December 31, 1995. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually from Washington headquarters and field offices of DOE; from the US Nuclear Regulatory Commission (NRC); from the US reactor manufacturers who are the principal nuclear contractors for foreign reactor locations; from US and foreign embassies; and from foreign governmental nuclear departments. The book consists of three divisions, as follows: (1) a commercial reactor locator map and tables of the characteristic and statistical data that follow; a table of abbreviations; (2) tables of data for reactors operating, being built, or planned; and (3) tables of data for reactors that have been shut down permanently or dismantled. The reactors are subdivided into the following parts: Civilian, Production, Military, Export, and Critical Assembly. Export reactor refers to a reactor for which the principal nuclear contractor is a US company--working either independently or in cooperation with a foreign company (Part 4). Critical assembly refers to an assembly of fuel and moderator that requires an external source of neutrons to initiate and maintain fission. A critical assembly is used for experimental measurements (Part 5).

  17. Nuclear reactors built, being built, or planned: 1995

    International Nuclear Information System (INIS)

    This report contains unclassified information about facilities built, being built, or planned in the US for domestic use or export as of December 31, 1995. The Office of Scientific and Technical Information, US Department of Energy, gathers this information annually from Washington headquarters and field offices of DOE; from the US Nuclear Regulatory Commission (NRC); from the US reactor manufacturers who are the principal nuclear contractors for foreign reactor locations; from US and foreign embassies; and from foreign governmental nuclear departments. The book consists of three divisions, as follows: (1) a commercial reactor locator map and tables of the characteristic and statistical data that follow; a table of abbreviations; (2) tables of data for reactors operating, being built, or planned; and (3) tables of data for reactors that have been shut down permanently or dismantled. The reactors are subdivided into the following parts: Civilian, Production, Military, Export, and Critical Assembly. Export reactor refers to a reactor for which the principal nuclear contractor is a US company--working either independently or in cooperation with a foreign company (Part 4). Critical assembly refers to an assembly of fuel and moderator that requires an external source of neutrons to initiate and maintain fission. A critical assembly is used for experimental measurements (Part 5)

  18. Small size modular fast reactors in large scale nuclear power

    International Nuclear Information System (INIS)

    The report presents an innovative nuclear power technology (NPT) based on usage of modular type fast reactors (FR) (SVBR-75/100) with heavy liquid metal coolant (HLMC) i. e. eutectic lead-bismuth alloy mastered for Russian nuclear submarines' (NS) reactors. Use of this NPT makes it possible to eliminate a conflict between safety and economic requirements peculiar to the traditional reactors. Physical features of FRs, an integral design of the reactor and its small power (100 MWe), as well as natural properties of lead-bismuth coolant assured realization of the inherent safety properties. This made it possible to eliminate a lot of safety systems necessary for the reactor installations (RI) of operating NPPs and to design the modular NPP which technical and economical parameters are competitive not only with those of the NPP based on light water reactors (LWR) but with those of the steam-gas electric power plant. Multipurpose usage of transportable reactor modules SVBR-75/100 of entirely factory manufacture assures their production in large quantities that reduces their fabrication costs. The proposed NPT provides economically expedient change over to the closed nuclear fuel cycle (NFC). When the uranium-plutonium fuel is used, the breeding ratio is over one. Use of proposed NPT makes it possible to considerably increase the investment attractiveness of nuclear power (NP) with fast neutron reactors even today at low costs of natural uranium. (authors)

  19. Nuclear Power Reactors in the World. 2016 Ed

    International Nuclear Information System (INIS)

    Nuclear Power Reactors in the World is an annual publication that presents the most recent data pertaining to reactor units in IAEA Member States. This thirty-sixth edition of Reference Data Series No. 2 provides a detailed comparison of various statistics up to and including 31 December 2015. The tables and figures contain the following information: — General statistics on nuclear reactors in IAEA Member States; — Technical data on specific reactors that are either planned, under construction or operational, or that have been shut down or decommissioned; — Performance data on reactors operating in IAEA Member States, as reported to the IAEA. The data compiled in this publication is a product of the IAEA’s Power Reactor Information System (PRIS). The PRIS database is a comprehensive source of data on all nuclear power reactors in the world. It includes specification and performance history data on operational reactors as well as on reactors under construction or in the decommissioning process. Data is collected by the IAEA via designated national correspondents in Member States

  20. An overview of future sustainable nuclear power reactors

    Directory of Open Access Journals (Sweden)

    Andreas Poullikkas

    2013-01-01

    Full Text Available In this paper an overview of the current and future nuclear power reactor technologies is carried out. In particular, the nuclear technology is described and the classification of the current and future nuclear reactors according to their generation is provided. The analysis has shown that generation II reactors currently in operation all around the world lack significantly in safety precautions and are prone to loss of coolant accident (LOCA. In contrast, generation III reactors, which are an evolution of generation II reactors, incorporate passive or inherent safety features that require no active controls or operational intervention to avoid accidents in the event of malfunction, and may rely on gravity, natural convection or resistance to high temperatures. Today, partly due to the high capital cost of large power reactors generating electricity and partly due to the consideration of public perception, there is a shift towards the development of smaller units. These may be built independently or as modules in a larger complex, with capacity added incrementally as required. Small reactors most importantly benefit from reduced capital costs, simpler units and the ability to produce power away from main grid systems. These factors combined with the ability of a nuclear power plant to use process heat for co-generation, make the small reactors an attractive option. Generally, modern small reactors for power generation are expected to have greater simplicity of design, economy of mass production and reduced installation costs. Many are also designed for a high level of passive or inherent safety in the event of malfunction. Generation III+ designs are generally extensions of the generation III concept, which include advanced passive safety features. These designs can maintain the safe state without the use of any active control components. Generation IV reactors, which are future designs that are currently under research and development, will

  1. Byelorussia's Chernobyl legacy

    International Nuclear Information System (INIS)

    Following the Chernobyl nuclear accident on 26 April 1986 radioactive fall-out was widely distributed over the eastern territories of the Soviet Union and over Europe. While the effects in Europe have been well documented and have received widespread media attention, less is known about the effects within the Soviet Union. The general picture that has been painted is that while the accident was serious, it wasn't that bad and the resulting contamination is something that can be lived with. In reality many people are living in contaminated zones which would be regarded as completely unacceptable in the United Kingdom. However, the USSR Ministry of Public Health has argued that relocation is not necessary. The Ministry and other agencies including the Red Cross do not recognize the contamination as serious and feel the main side effect of Chernobyl is psychological. In Byelorussia however, 100,000 people are still living in areas of major contamination. (author)

  2. Chernobyl: The aftermath

    International Nuclear Information System (INIS)

    The nuclear accident in Chernobyl prompted vehement and sometimes controversial public and political reaction in the Federal Republic of Germany, as it did elsewhere. What remained after the initial concern subsided? We at the IIUG feel obligated to make a contribution to the preservation and the improvement of our environmental quality, both in basic and specialized research aimed at environmental problems. It is time to take stock of the findings of our own work; we must access the feedback to and implementation of this research; the candidness and integrity of the scientific-economic-political community; superfluous knowledge or information gaps; structural obstacles and possible alternatives. This paper presents, in condensed form, the results of the 'post-Chernobyl' discussions at the IIUG, based on our work in various projects. (orig.)

  3. Comparative Analysis of Remediation Strategies and Experience After the Fukushima Daiichi and Chernobyl Nuclear Accidents. Annex IV of Technical Volume 5

    International Nuclear Information System (INIS)

    Significant environmental contamination by radioactive materials has occurred in some parts of the world due to industrial and military activities, such as nuclear weapon testing, uranium mining and nuclear and radiological accidents. The most well-known sites where large scale remediation has been implemented include: the nuclear test sites in the Bikini and Enewetak Atolls (USA) and Maralinga (Australia); areas contaminated by nuclear accidents at Kyshtym, Chernobyl (former Soviet Union) and Fukushima (Japan); Goiânia (Brazil), following the loss of a radioactive source; and Palomares (Spain), after the B-52 bomber accident. These sites differed in terms of contamination levels, the main dose forming radionuclides and environmental characteristics. Consequently, different remediation criteria and strategies were used to protect the affected population and remediate the environment

  4. LONG-TERM DYNAMICS OF RADIONUCLIDE VERTICAL MIGRATION IN SOILS OF THE CHERNOBYL NUCLEAR POWER PLANT EXCLUSION ZONE

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E

    2009-11-19

    The radioactive fallout from the Chernobyl Nuclear Power Plant (ChNPP) accident consisted of fuel and condensation components. An important radioecological task associated with the late phase of the accident is to evaluate the dynamics of radionuclide mobility in soils. Identification of the variability (or invariability) in the radionuclide transfer parameters makes it possible to (1) accurately predict migration patterns and biological availability of radionuclides and (2) evaluate long-term exposure trends for the population who may reoccupy the remediated abandoned areas. In 1986-1987, a number of experimental plots were established within various tracts of the fallout plume to assist with the determination of the long-term dynamics of radionuclide vertical migration in the soils. The transfer parameters for {sup 137}Cs, {sup 90}Sr, and {sup 239,240}Pu in the soil profile, as well as their ecological half-time of the radionuclide residence (T{sub 1/2}{sup ecol}) values in the upper 5-cm thick soil layers of different grasslands were estimated at various times since the accident. Migration characteristics in the grassland soils tend to decrease as follows: {sup 90}Sr > {sup 137}Cs {ge} {sup 239,240}Pu. It was found that the {sup 137}Cs absolute T{sub 1/2}{sup ecol} values are 3-7 times higher than its radioactive decay half-life value. Therefore, changes in the exposure dose resulting from the soil deposited {sup 137}Cs now depend only on its radioactive decay. The {sup 90}Sr T{sub 1/2}{sup ecol} values for the 21st year after the fallout tend to decrease, indicating an intensification of its migration capabilities. This trend appears consistent with a pool of mobile {sup 90}Sr forms that grows over time due to destruction of the fuel particles.

  5. Internuclear chromosome bridges in thyrocytes of papillary thyroid cancer in patients, subjected to radioactive iodine isotopes during first months after the accident at the Chernobyl nuclear power plant

    Directory of Open Access Journals (Sweden)

    Kravtsov V.Iu.

    2015-12-01

    Full Text Available Background. Fallout from Chernobyl accident was primarily to iodine radioisotopes, with Iodine-131 (I-131 being the most predominant. Radioiodines accumulated following the accident could induce pathologic changes in thyrocytes. Internuclear chromatine bridges and ‘‘tailed’’nuclei - broken bridge fragments - are considered like cytopathological effects of radiation exposure as these abnormalities are formed from dicentric chromosomes, which are established markers of radiation exposure. Objective. To test the possibility that internuclear bridges and tailed nuclei are cytological markers of radiation exposure of the thyroid. Methods. We investigated thyrocyte nuclear abnormalities in cytological samples from fine-needle aspiration biopsy in papillary thyroid cancer patients exposed to radioiodine after Chernobyl accident (35 subjects from Gomel region, Belarus and in papillary thyroid cancer of unexposed patients (25 subjects from Leningrad region, Russia. Nuclear abnormalities included internuclear bridges and ‘‘tailed’’ nuclei were examined. Results. Cells in papillary thyroid cancer of irradiated patients are characterized by the high frequency of appearance of hole nucleoplasmic bridges as well as broken bridges in comparison with the control group. The average frequency of thyrocytes with bridges in irradiated patients was almost 4 times higher than that in the unexposed group (4,69±0,69‰ vs. 1,10±0,23 ‰, p<0.001. The same contrast was observed in parameter “frequency of thyrocytes with “tailed” nuclei” (12,40±1,82 ‰ vs 3,68±0,39 ‰, (p<0.001. Conclusion. Thyrocytes with internuclear bridges may be considered as markers of radiation effects on the thyroid gland. Citation: Kravtsov VIu, Ibragimova NV, Nikonovich SN, Nadyrov EA, Rozhko AV. [Internuclear chromosome bridges in thyrocytes of papillary thyroid cancer in patients, subjected to radioactive iodine isotopes during first months after the accident at

  6. Advances in zirconium technology for nuclear reactor application

    International Nuclear Information System (INIS)

    Zirconium alloys are extensively used as a material for cladding nuclear fuels and for making core structurals of water-cooled nuclear power reactors all over the world for generation of nearly 16 percent of the worlds electricity. Only four countries in the world, namely France, USA, Russia and India, have large zirconium industry and capability to manufacture reactor grade zirconium sponge, a number of zirconium alloys and a wide variety of structural components for water cooled nuclear reactor. The present paper summarises the status of zirconium technology and highlights the achievement of Nuclear Fuel Complex during the last ten years in developing a wide variety of zirconium alloys and components for water-cooled nuclear power programme

  7. Control of WWER-440 nuclear reactor

    International Nuclear Information System (INIS)

    The V-1 reactor control systems are described. The data acquisition and processing system fulfils four main functions, ie., reactor start-up and power increase to 10% of the rated power, automatic power control within 3% and 110% of the rated power, reactivity compensation, and reactor protection. The automatic control system ensures constant steam pressure maintained with an accuracy of +-0.05 MPa. Reactivity compensation and spatial power distribution is mainly safeguarded by boric acid control. The V-1 reactor protection system has four levels of accident protection depending on the gravity of the failure. The philosophy of automation of the V-1 reactor control and protection system is based on autonomous automatic controlers and on the direct control of the individual sets and technological equipment. In conclusion, development trends are briefly outlined of control and protection systems of light water reactor power plants. (Z.M.)

  8. Programming for a nuclear reactor instrument simulator

    International Nuclear Information System (INIS)

    A new computerized control system for a transient test reactor incorporates a simulator for pre-operational testing of control programs. The part of the simulator pertinent to the discussion here consists of two microprocessors. An 8086/8087 reactor simulator calculates simulated reactor power by solving the reactor kinetics equations. An 8086 instrument simulator takes the most recent power value developed by the reactor simulator and simulates the appropriate reading on each of the eleven reactor instruments. Since the system is required to run on a one millisecond cycle, careful programming was required to take care of all eleven instruments in that short time. This note describes the special programming techniques used to attain the needed performance

  9. RA nuclear reactor - revitalisation, renewal and applications

    International Nuclear Information System (INIS)

    This book is meant to give professional support in solving the problem of RA reactor, its revitalisation and renewal, as a special help for decision makers. Facts in favor of restarting RA reactor are prevailing. This report is made of six parts. First part includes an overview of basic properties of research reactors in the world and a discussion concerning their future development. RA reactor parameters are analyzed both with low enriched and highly enriched fuel and it has been concluded that the aim of RA reactor renewal should be to obtaining as high as possible thermal neutron flux density. The second part deals with possible applications of RA reactor in fundamental and applied research programs, commercial applications and its role in education and training programs. The third part discusses application of RA reactor as a source of thermal neutrons for fundamental and applied sciences, especially in the condensed matter physics and development of new materials. The role of RA reactor in development of radiation protection systems is emphasised in part four. Some possible commercial applications of Ra reactor are described in part five: isotope production, and their different applications. Part six deals with education and training of staff, with special accent on scientific international cooperation. Basic conclusions of this material meant for decision makers are: restarting RA reactor is the most reasonable and activities related to its revitalisation and renewal should be continued; this program should include solving the problems of education and training of the staff for reactor operation, improvement and different applications; renewal program should include renewal of the experimental devices as a condition of reactor efficient application immediately after its startup

  10. Vertical distribution and estimated doses from artificial radionuclides in soil samples around the Chernobyl nuclear power plant and the Semipalatinsk nuclear testing site.

    Directory of Open Access Journals (Sweden)

    Yasuyuki Taira

    Full Text Available For the current on-site evaluation of the environmental contamination and contributory external exposure after the accident at the Chernobyl Nuclear Power Plant (CNPP and the nuclear tests at the Semipalatinsk Nuclear Testing Site (SNTS, the concentrations of artificial radionuclides in soil samples from each area were analyzed by gamma spectrometry. Four artificial radionuclides ((241Am, (134Cs, (137Cs, and (60Co were detected in surface soil around CNPP, whereas seven artificial radionuclides ((241Am, (57Co, (137Cs, (95Zr, (95Nb, (58Co, and (60Co were detected in surface soil around SNTS. Effective doses around CNPP were over the public dose limit of 1 mSv/y (International Commission on Radiological Protection, 1991. These levels in a contaminated area 12 km from Unit 4 were high, whereas levels in a decontaminated area 12 km from Unit 4 and another contaminated area 15 km from Unit 4 were comparatively low. On the other hand, the effective doses around SNTS were below the public dose limit. These findings suggest that the environmental contamination and effective doses on the ground definitely decrease with decontamination such as removing surface soil, although the effective doses of the sampling points around CNPP in the present study were all over the public dose limit. Thus, the remediation of soil as a countermeasure could be an extremely effective method not only for areas around CNPP and SNTS but also for areas around the Fukushima Dai-ichi Nuclear Power Plant (FNPP, and external exposure levels will be certainly reduced. Long-term follow-up of environmental monitoring around CNPP, SNTS, and FNPP, as well as evaluation of the health effects in the population residing around these areas, could contribute to radiation safety and reduce unnecessary exposure to the public.

  11. Economic viability of innovative nuclear reactor and fuel cycle technologies

    International Nuclear Information System (INIS)

    Full text: Nuclear power has established its position as one of the most stable electricity supply sources in many countries in the world, supplying about 17% of total electricity generated. However, in order to keep that position, there are two important challenges that nuclear energy will face in the coming decades. They are: competition, and social/political acceptance (including non-proliferation and terrorism). There is an increasing concern that existing nuclear technologies may not be able to overcome such tough challenges. It is expected that innovative technologies can be a part of the solutions to overcome such challenges. This paper focuses on economic viability of innovative nuclear reactor and its associated fuel cycle technologies. First, it is important to consider the long term energy paths and potential role of nuclear power under different scenarios. We applied global energy optimization model based on IPCC scenarios. Then, we look at Japan, where electricity market is being liberalized, in order to explore how liberalization will have influence economic viability of nuclear power. The following are our basic conclusions: CO2 constraints as well as power generation cost competitiveness could affect future growth of nuclear power quite significantly. Current trend suggests that nuclear power would not grow much without CO2 constraints, or even face minus growth if its power generation cost became higher. On the other hand, cost reduction with CO2 constraints could accelerate future expansion of nuclear power quite significantly; In addition to life-long average generation cost, other investment criteria (such as asset productivity) may become critically important under the liberalized market. Under the liberalized electricity market, short term investment criteria could become more important than 30 year life time average cost. This suggests that small initial investment is more acceptable than large capital investment. Advanced nuclear reactor

  12. The human consequences of the Chernobyl nuclear accident. A strategy for recovery. A report commissioned by UNDP and UNICEF with the support of UN-OCHA and WHO. Final - 25.01.02

    International Nuclear Information System (INIS)

    This Report contains the findings of a study conducted into the human consequences of the Chernobyl nuclear accident fifteen years after the explosion. The Mission explored the health, socio-economic and environmental effects of the accident and the events that followed. The Report contains an analysis of the current situation and the prospects for the future, focusing on aspects that are significant for the well-being of the people and communities directly affected. The affected population - those exposed to radioactive fallout, remaining in the affected areas, or forced to relocate - continue to face disproportionate suffering in terms of health, social conditions, and economic opportunity. Hundreds of thousands of people have been evacuated from the most severely affected areas. Many have found it difficult to adapt and continue to face serious psychological, economic and social problems. The process of evacuation has now virtually ceased and only a small number of people continue to live in the most polluted areas. However, some tens of thousands remain in areas polluted to a level of between 15 and 40 curies per square kilometre. The accident has also had a continuing impact on the opportunities and well-being of a much wider circle of the inhabitants of Belarus, Ukraine and Russia, through the negative image that it has created for large areas of these countries. It has imposed a heavy burden on the national budgets through the cost of clean-up, compensation and recovery. Ukraine, in addition, has had to carry much of the cost of closing and making safe the Chernobyl complex as well as the opportunity cost of the lost electrical output from the reactors concerned. These commitments have diverted resources away from other priorities, such as health, education and investment, at a time of profound economic crisis

  13. Dynamic stability of a fluidized-bed nuclear reactor

    International Nuclear Information System (INIS)

    Recent advances in the study of a fluidized-bed nuclear reactor's stability, due to short and long time transients, are discussed. The point-kinetic model, which considers flux variation in the axial direction, is applied to study short time transients, and the theory of bifurcation is used for long time transients. Numerical results are presented for both transients. The preliminary results indicate that this concept of a nuclear reactor has a behavior similar to that of a conventional reactor regarding its dynamic stability

  14. Classroom simulators. User friendly education with nuclear reactor simulators

    International Nuclear Information System (INIS)

    Through its programmes the IAEA is sponsoring the development of nuclear reactor simulators that operate on personal computers and simulate response of a number of reactor types to operating and accident conditions. The simulators provide training tools for university professors and engineers involved in teaching topics in nuclear energy and are also supplied directly to students, junior engineers, and senior engineers and scientists interested in understanding the topics. This article describes the simulation programmes sponsored by the IAEA. Four different programmes are available covering different types of reactors: PWRs, BWRs, HWRs

  15. Environmental monitoring data around the Chernobyl nuclear power plant used in the cooperative research project between JAERI and CHESCIR (Ukraine). Cooperative research

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Takashi; Matsunaga, Takeshi; Amano, Hikaru [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Tkachenko, Yuri; Kovalyov, Alexandr; Sukhoruchkin, Andrei; Derevets, Varely [The State Enterprise for Region Monitoring of Environment and Dosimetric Control (Ukraine)

    2003-01-01

    This report is a compilation of the shared data derived from the environmental monitoring by RADEK (The state Enterprise for Region Monitoring of Environment and Dosimetric Control of Ukraine) and the record of environmental characteristics derived from field observations during a research project (1992-1999) between JAERI (Japan Atomic Energy Research Institute) and CHESCIR (Chernobyl Science and Technology Centre for International Research). The compiled data in this report are especially related to one particular research subject (Subject-3) of the project on the migration of radionuclides released into the terrestrial and aquatic environments after a nuclear accident. The present report shows the basis of published works concerning Subject-3. (author)

  16. Long-term therapy for polymorphic mental disorders in liquidators of the consequences of the accident at the Chernobyl nuclear power plant

    Directory of Open Access Journals (Sweden)

    V. N. Krasnov

    2012-01-01

    Full Text Available The paper gives the results of a long-term comparative therapeutic study of a large cohort of more than 500 liquidators of the consequences of the accident at the Chernobyl nuclear power plant in 1986. The patients were followed up (and periodically treated at hospital 5 years or more, usually 10—15 years. The study confirmed mainly the cerebrovascular nature of disorders following the pattern seen in moderate psychoorganic syndrome. Therapy with cerebroprotective agents having vascular vegetotropic properties could yield certain therapeutic results and, to some extent, preserve social functioning capacity in these patients.

  17. The ecology of the Chernobyl catastrophe. Scientific outlines of an international programme of collaborative research

    International Nuclear Information System (INIS)

    The Chernobyl disaster was the largest civil nuclear catastrophe of all time. When reactor number 4 of the Chernobyl nuclear power plant exploded on 26 April 1986, it permanently changed the lives of more than 4 million people living in Belarus, Ukraine and Russia, shaking the fabric of an area almost the size of England, and triggering a whole swathe of environmental, economic, social, medical and political repercussions. At first the Soviet Union tackled the aftermath alone but, by 1990, with the process of change associated with perestroika, the three affected states of Belarus, Ukraine and the Federation of Russia appealed to the international community for solidarity and help. In co-operation with other agencies of the United Nations system, the UNESCO Chernobyl Programme was launched , with the formal signing of an agreement in January 1991 between the three republics and UNESCO. Since then, some twenty projects have been carried out in UNESCO's various fields of competence - education, science, culture and communication. The volume reviews eight years of study on the impact of Chernobyl on natural ecosystems, agro-ecosystems, human ecology, biological diversity, and genetic and socio-economic systems. It comprises eight chapters. The first three chapters discuss the effects of the high levels of radionuclides released from the Chernobyl reactor on the environment, on natural ecosystems and on agro-ecosystems. The fourth chapter, on human ecology, covers both the human effects at the time of the disaster and those still continuing today. Chapters five and six describe the impact of radionuclide release on biological diversity and genetic systems respectively. The socioeconomic effects of the catastrophe are discussed in chapter seven. Each of these seven chapters ends with scientific hypotheses and research recommendations, with a final chapter providing a detailed description of the setting up and aims of the multinational and multidimensional Chernobyl

  18. Chernobyl - a Canadian technical perspective

    International Nuclear Information System (INIS)

    In this report we present the design review done to date in Canada by AECL. From the Canadian point of view it covers: 1) relevant information on the Chernobyl design and the accident, both as presented by the Soviets at the Post-Accident Review Meeting (PARM) held in Vienna from August 25-29, 1986, and as deduced from publicly available Soviet documentation; and 2) details of AECL's technical review of the CANDU PHWR (Pressurized Heavy Water Reactor) against the background of the Chernobyl accident, and implications of the Chernobyl accident. Reviews of operational aspects are underway by the Canadian electrical utilities and a review by the Canadian regulatory agency (the Atomic Energy Control Board) is near completion

  19. On the possible physical mechanism of Chernobyl catastrophe and the unsoundness of official conclusion

    CERN Document Server

    Rukhadze, A A; Filippov, D V

    2003-01-01

    The official conclusion about the origin and mechanism of the Chernobyl catastrophe is shown to essentially contradict experimental facts available from the accident. In the frame of existing physical models of nuclear fission reactor, it is shown analytically that under conditions of the accident the period of runaway of reactor at the fourth power generating unit of the Chernobyl Nuclear Power Plant (CNPP) should be either 10 times slower or 100 times faster than that observed. A self-consistent hypothesis is suggested for the probable birth of magnetic charges, during the turbine generator test under it's own momentum test, at the fourth power generating unit of CNPP, and for the impact of these charges on the reactivity coefficient.

  20. An introduction to the engineering of fast nuclear reactors

    CERN Document Server

    Judd, Anthony M

    2014-01-01

    An invaluable resource for both graduate-level engineering students and practising nuclear engineers who want to expand their knowledge of fast nuclear reactors, the reactors of the future! This book is a concise yet comprehensive introduction to all aspects of fast reactor engineering. It covers topics including neutron physics; neutron flux spectra; flux distribution; Doppler and coolant temperature coefficients; the performance of ceramic and metal fuels under irradiation, structural changes, and fission-product migration; the effects of irradiation and corrosion on structural materials, irradiation swelling; heat transfer in the reactor core and its effect on core design; coolants including sodium and lead-bismuth alloy; coolant circuits; pumps; heat exchangers and steam generators; and plant control. The book includes new discussions on lead-alloy and gas coolants, metal fuel, the use of reactors to consume radioactive waste, and accelerator-driven subcritical systems.

  1. Organization of fire protection services and fire fighting tactics in nuclear power plants taking into account conclusions from the Chernobyl accident

    International Nuclear Information System (INIS)

    The paper deals with the problems of organizing fire services to protect nuclear power plants, and gives an overview of their structure and the basic tasks they perform. Operational documentation on the extinguishing of fires and the elimination of the consequences of accidents is examined, as are the principles governing co-operation between plant operating personnel and other services drawn on for such work (dosimetric, health, etc.). The problems of training firemen to combat fires under conditions specific to nuclear power plants are reviewed, as are those relating to the organization and carrying out of joint fire fighting training work with plant service personnel, and to the psychological aspects of firemen's training. The paper discusses the most characteristic types of fire, where they occur and how they develop, together with fire fighting conditions under high levels of radiation. In the light of the experience gained while extinguishing the fire and eliminating the consequences of the accident at the Chernobyl nuclear power plant, a description is given of the special technical equipment and resources used for the personal monitoring of firemen and for their protection against the effects of radioactive substances. The fire extinguishing techniques and methods used at the Chernobyl plant are described, as well as the measures which have been implemented in fire service as a result of the experience accumulated during this accident. (author). 5 figs, 1 tab

  2. Nuclear data and reactor physics activities in Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Liem, P.H. [National Atomic Energy Agency, Tangerang (Indonesia). Center for Multipurpose Reactor

    1998-03-01

    The nuclear data and reactor physics activities in Indonesia, especially, in the National Atomic Energy Agency are presented. In the nuclear data field, the Agency is now taking the position of a user of the main nuclear data libraries such as JENDL and ENDF/B. These nuclear data libraries become the main sources for producing problem dependent cross section sets that are needed by cell calculation codes or transport codes for design, analysis and safety evaluation of research reactors. In the reactor physics field, besides utilising the existing core analysis codes obtained from bilateral and international co-operation, the Agency is putting much effort to self-develop Batan`s codes for reactor physics calculations, in particular, for research reactor and high temperature reactor design, analysis and fuel management. Under the collaboration with JAERI, Monte Carlo criticality calculations on the first criticality of RSG GAS (MPR-30) first core were done using JAERI continuous energy, vectorized Monte Carlo code, MVP, with JENDL-3.1 and JENDL-3.2 nuclear data libraries. The results were then compared with the experiment data collected during the commissioning phase. Monte Carlo calculations with both JENDL-3.1 and -3.2 libraries produced k{sub eff} values with excellent agreement with experiment data, however, systematically, JENDL-3.2 library showed slightly higher k{sub eff} values than JENDL-3.1 library. (author)

  3. Pellet bed reactor concepts for nuclear propulsion applications

    Energy Technology Data Exchange (ETDEWEB)

    El-Genk, M.S.; Morley, N.J.; Pelaccio, D.G.; Juhasz, A. [Univ of New Mexico, Albuquerque, NM (United States)

    1994-11-01

    Pellet bed reactor (PeBR) concepts have been developed for nuclear thermal and nuclear electric propulsion, and bimodal applications. This annular core, fast spectrum reactor offers many desirable design and safety features. These features include high-power density, small reactor size, full retention of fission products, passive decay heat removal, redundancy in reactor control, negative temperature reactivity feedback, ground testing of the fully assembled reactor using electric heating and nonnuclear fuel elements, and the option of fueling on the launch pad or fueling and refueling in orbit. In addition to these features, the concepts for nuclear electric propulsion and for bimodal power and thermal propulsion have no single point failure. The average power density in the reactor for nuclear thermal propulsion ranges from 2.2 to 3.3 MW/I and for a 15-MWe nuclear electric propulsion system the total power system specific mass is about 3.3 kg/kWe. The bimodal-PeBR system concepts offer specific impulse in excess of 650 s, tens of Newtons of thrust, and total system specific power ranging from 11 to 21.9 We/kg at the 10- and 40-kWe levels, respectively. 35 refs.

  4. Fast reactors: the future of nuclear energy

    International Nuclear Information System (INIS)

    The main problems to be solved for FBR type reactors become viable economically, presenting the research programs of Europe, United States of America, Japan and Brazil are described. The cooperations between interested countries for improving FBR type reactors, and the financial and human resources necessaries for the development of programs, are evaluated. The fuel cycle is also analysed. (M.C.K.)

  5. Linear regression and sensitivity analysis in nuclear reactor design

    International Nuclear Information System (INIS)

    Highlights: • Presented a benchmark for the applicability of linear regression to complex systems. • Applied linear regression to a nuclear reactor power system. • Performed neutronics, thermal–hydraulics, and energy conversion using Brayton’s cycle for the design of a GCFBR. • Performed detailed sensitivity analysis to a set of parameters in a nuclear reactor power system. • Modeled and developed reactor design using MCNP, regression using R, and thermal–hydraulics in Java. - Abstract: The paper presents a general strategy applicable for sensitivity analysis (SA), and uncertainity quantification analysis (UA) of parameters related to a nuclear reactor design. This work also validates the use of linear regression (LR) for predictive analysis in a nuclear reactor design. The analysis helps to determine the parameters on which a LR model can be fit for predictive analysis. For those parameters, a regression surface is created based on trial data and predictions are made using this surface. A general strategy of SA to determine and identify the influential parameters those affect the operation of the reactor is mentioned. Identification of design parameters and validation of linearity assumption for the application of LR of reactor design based on a set of tests is performed. The testing methods used to determine the behavior of the parameters can be used as a general strategy for UA, and SA of nuclear reactor models, and thermal hydraulics calculations. A design of a gas cooled fast breeder reactor (GCFBR), with thermal–hydraulics, and energy transfer has been used for the demonstration of this method. MCNP6 is used to simulate the GCFBR design, and perform the necessary criticality calculations. Java is used to build and run input samples, and to extract data from the output files of MCNP6, and R is used to perform regression analysis and other multivariate variance, and analysis of the collinearity of data

  6. Development of nuclear reactor and nonreactor regulation in Indonesia

    International Nuclear Information System (INIS)

    This paper describes the government regulation draft of Nuclear Reactor Licensing in Indonesia for governing the conduct of activities relating to the licensing of rector nuclear. The draft has been discussing between regulatory body and relevant departmental. The draft immediately will finish and will be enacted. (author)

  7. Economics and utilization of thorium in nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    1978-05-01

    Information on thorium utilization in power reactors is presented concerning the potential demand for nuclear power, the potential supply for nuclear power, economic performance of thorium under different recycle policies, ease of commercialization of the economically preferred cases, policy options to overcome institutional barriers, and policy options to overcome technological and regulatory barriers.

  8. Monitoring Akkuyu Nuclear Reactor Using Anti-Neutrino Flux Measurement

    CERN Document Server

    Ozturk, Sertac; Ozcan, V Erkcan; Unel, Gokhan

    2016-01-01

    We present a simulation based study for monitoring Akkuyu Nuclear Power Plant's activity using anti-neutrino flux originating from the reactor core. A water Cherenkov detector has been designed and optimization studies have been performed using Geant4 simulation toolkit. A first study for the design of a monitoring detector facility for Akkuyu Nuclear Power Plant has been discussed in this paper.

  9. 77 FR 3009 - Knowledge and Abilities Catalog for Nuclear Power Plant Operators: Advanced Boiling Water Reactors

    Science.gov (United States)

    2012-01-20

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION Knowledge and Abilities Catalog for Nuclear Power Plant Operators: Advanced Boiling Water Reactors..., ``Knowledge and Abilities Catalog for Nuclear Power Plant Operators: Advanced Boiling Water Reactors.''...

  10. 76 FR 14437 - Economic Simplified Boiling Water Reactor Standard Design: GE Hitachi Nuclear Energy; Issuance of...

    Science.gov (United States)

    2011-03-16

    ... From the Federal Register Online via the Government Publishing Office ] NUCLEAR REGULATORY COMMISSION Economic Simplified Boiling Water Reactor Standard Design: GE Hitachi Nuclear Energy; Issuance of... GE Hitachi Nuclear Energy (GEH) for the economic simplified boiling water reactor (ESBWR)...

  11. New reactor technology: safety improvements in nuclear power systems.

    Science.gov (United States)

    Corradini, M L

    2007-11-01

    Almost 450 nuclear power plants are currently operating throughout the world and supplying about 17% of the world's electricity. These plants perform safely, reliably, and have no free-release of byproducts to the environment. Given the current rate of growth in electricity demand and the ever growing concerns for the environment, nuclear power can only satisfy the need for electricity and other energy-intensive products if it can demonstrate (1) enhanced safety and system reliability, (2) minimal environmental impact via sustainable system designs, and (3) competitive economics. The U.S. Department of Energy with the international community has begun research on the next generation of nuclear energy systems that can be made available to the market by 2030 or earlier, and that can offer significant advances toward these challenging goals; in particular, six candidate reactor system designs have been identified. These future nuclear power systems will require advances in materials, reactor physics, as well as thermal-hydraulics to realize their full potential. However, all of these designs must demonstrate enhanced safety above and beyond current light water reactor systems if the next generation of nuclear power plants is to grow in number far beyond the current population. This paper reviews the advanced Generation-IV reactor systems and the key safety phenomena that must be considered to guarantee that enhanced safety can be assured in future nuclear reactor systems.

  12. New reactor technology: safety improvements in nuclear power systems.

    Science.gov (United States)

    Corradini, M L

    2007-11-01

    Almost 450 nuclear power plants are currently operating throughout the world and supplying about 17% of the world's electricity. These plants perform safely, reliably, and have no free-release of byproducts to the environment. Given the current rate of growth in electricity demand and the ever growing concerns for the environment, nuclear power can only satisfy the need for electricity and other energy-intensive products if it can demonstrate (1) enhanced safety and system reliability, (2) minimal environmental impact via sustainable system designs, and (3) competitive economics. The U.S. Department of Energy with the international community has begun research on the next generation of nuclear energy systems that can be made available to the market by 2030 or earlier, and that can offer significant advances toward these challenging goals; in particular, six candidate reactor system designs have been identified. These future nuclear power systems will require advances in materials, reactor physics, as well as thermal-hydraulics to realize their full potential. However, all of these designs must demonstrate enhanced safety above and beyond current light water reactor systems if the next generation of nuclear power plants is to grow in number far beyond the current population. This paper reviews the advanced Generation-IV reactor systems and the key safety phenomena that must be considered to guarantee that enhanced safety can be assured in future nuclear reactor systems. PMID:18049233

  13. Reconstruction of the Chernobyl emergency and accident management

    International Nuclear Information System (INIS)

    Full text of publication follows: on April 26, 1986 the most serious civil technological accident in the history of mankind occurred of the Chernobyl Nuclear Power Plant (ChNPP) in the former Soviet Union. As a direct result of the accident, the reactor was severely destroyed and large quantities of radionuclides were released. Some 800000 persons, also called 'liquidators' - including plant operators, fire-fighters, scientists, technicians, construction workers, emergency managers, volunteers, as well as medical and military personnel - were part of emergency measurements and accident management efforts. Activities included measures to prevent the escalation of the accident, mitigation actions, help for victims as well as activities in order to provide a basic infrastructure for this unprecedented and overwhelming task. The overall goal of the 'Project Chernobyl' of the Institute of Risk Research of the University of Vienna was to preserve for mankind the experience and knowledge of the experts among the 'liquidators' before it is lost forever. One method used to reconstruct the emergency measures of Chernobyl was the direct cooperation with liquidators. Simple questionnaires were distributed among liquidators and a database of leading accident managers, engineers, medical experts etc. was established. During an initial struggle with a number of difficulties, the response was sparse. However, after an official permit had been issued, the questionnaires delivered a wealth of data. Furthermore a documentary archive was established, which provided additional information. The multidimensional problem in connection with the severe accident of Chernobyl, the clarification of the causes of the accident, as well as failures and successes and lessons to be learned from the Chernobyl emergency measures and accident management are discussed. (authors)

  14. Regional distribution of Chernobyl-derived plutonium deposition in Finland

    International Nuclear Information System (INIS)

    The Chernobyl nuclear power plant accident in April 1986 caused a widely spread plume of radionuclides containing, amongst other materials, plutonium isotopes. The regional deposition of these nuclides in Finland has been assessed, based on samples of lichen, peat, precipitation, surface soil and grass. Unlike the deposition of transuranium elements from the weapons tests in the 1950's and the 1960's, the deposition in Finland from the Chernobyl accident was very unevenly distributed. Even then, the Chernobyl-derived deposition of 239,240Pu in the most contaminated regions of Finland was only around 10% of the global fallout from weapons tests. The total amount of 239,240Pu deposited in Finland was 1 x 1011 Bq (∼25 g), i.e., approximately half of a percent of the activity deposited in the 1950's and the 1960's. In addition to the alpha-emitting Pu isotopes, the Chernobyl plume also contained a significant amount of the beta-emitting 241Pu, which is the precursor of the long-lived alpha-emitter 241Am. The highest plutonium deposition values were found in a relatively narrow swath from the southwestern coast of Finland northeastwards across the country. This is related to the calculated route of the air parcel trajectory associated with the initial explosion of the Chernobyl reactor. The high deposition values found in the northeastern part of the plume route over Finland can be attributed to the simultaneous occurrence of precipitation. The relatively high plutonium deposition in the southwestern part of Finland occurred, however, without concurrent precipitation. This indicates that the plutonium was at least partly associated with relatively large particles having a substantial deposition velocity due to gravitational setting. (author)

  15. Predicting material release during a nuclear reactor accident

    OpenAIRE

    KONINGS Rudy; Wiss, Thierry; BENES ONDREJ

    2014-01-01

    The accident in the Fukushima Daiichi nuclear power plant that happened four years ago this month, has once more drawn the attention of a broad public to the environmental impact of the release of fission products from nuclear power reactors in the event of an accident in which the reactor core is damaged. So far three such accidents have occurred in the history of civil nuclear power production. In this commentary we will review the state-of-the-art of the knowlegde of the physical and chemi...

  16. Spent nuclear fuel discharges from US reactors 1992

    Energy Technology Data Exchange (ETDEWEB)

    1994-05-05

    This report provides current statistical data on every fuel assembly irradiated in commercial nuclear reactors operating in the United States. It also provides data on the current inventories and storage capacities of those reactors to a wide audience, including Congress, Federal and State agencies, the nuclear and electric industries and the general public. It uses data from the mandatory, ``Nuclear Fuel Data`` survey, Form RW-859 for 1992 and historical data collected by the Energy Information Administration (EIA) on previous Form RW-859 surveys. The report was prepared by the EIA under a Memorandum of Understanding with the Office of Civilian Radioactive Waste Management.

  17. The new competition in the world market for nuclear reactors

    International Nuclear Information System (INIS)

    The current revival in the world market for nuclear reactors, notwithstanding Fukushima, completes the re-composition of the world's nuclear industry that started in the early 1990's and which has displaced nuclear power's centre of gravity towards Asia. In this new context, the capability to provide full-fledged financing for the buyers and to set up consortia that may include the operator have become major advantages at this stage, relegating to a lower order the ability to supply reactors with a high level of safety. (author)

  18. Nuclear data for radiation damage estimates for reactor structural materials

    International Nuclear Information System (INIS)

    The IAEA Consultants' Meeting on Nuclear Data for Radiation Damage Estimates for Reactor Structural Materials was convened by the IAEA Nuclear Data Section in Santa Fe, New Mexico, USA from 20-22 May 1985. The meeting was attended by 17 participants from 10 countries and 2 international organizations. The main objectives of the meeting were to review the status of displacement cross sections and the requirements for nuclear data needed for radiation damage estimates in reactor structural materials, and to develop recommendations for future activities in this field. This publication contains the text of all the papers prepared especially for this meeting including the conclusions and recommendations worked out during the meeting

  19. The EPR nuclear reactor: a dangerous and useless project

    International Nuclear Information System (INIS)

    After a presentation of the EPR (European Pressurized Reactor) concept and a discussion of the associated risks for the French nuclear industry, the contributions analyse the role the EPRs would have within the next 30 years, discuss the lifetimes of nuclear plants and new reactor types, discuss the impact of nuclear policies on the greenhouse effect by 2050 at the national and world scale, discuss the EPR economic aspect (the KWh cost), and discuss the social implications of a choice between the EPR and renewable energies

  20. OECD Nuclear Energy Agency Activities Related to Fast Reactor Development

    International Nuclear Information System (INIS)

    The OECD Nuclear Energy Agency (NEA), whose role is to assist its member countries to develop, through international cooperation, the scientific and technological bases required for the safe, environmentally friendly and economical use of nuclear energy, conducts work related to fast reactor systems in two areas of activity: one focused on scientific research and technology development needs and one dedicated to strategic and policy issues. Recent, scientifically oriented, fast reactor related activities coordinated by the NEA comprise: -A coordinated effort to evaluate basic nuclear data needed for the development of fast reactor systems; -A recently initiated review of Integral Experiments for Minor Actinide Management; -An ongoing study on Homogeneous versus Heterogeneous Recycle of Transuranic Isotopes in Fast Reactors; -A comparative analysis of the safety characteristics of sodium cooled fast reactors; -A series of workshops on Advanced Reactors with Innovative Fuels; -A series of information exchange meetings on actinide and fission product partitioning and transmutation. The NEA has also conducted two reviews on issues related to the transition from thermal to fast neutron nuclear systems. One study was devoted to technical issues, including benchmark studies on: (i) the performance of scenario analysis codes, (ii) a regional (European) scenario and (iii) a global transition scenario. The other study emphasized issues of interest to policymakers, such as key parameters affecting the cost-benefit analysis of transitioning, including the size and age of the nuclear reactor fleet, the expected future reliance on nuclear energy, access to uranium resources, domestic nuclear infrastructure and technology development, and radioactive waste management policy in place. The NEA is also an active player in many other international activities related to fast neutron systems, such as the Generation IV International Forum, where the NEA acts as technical secretariat for

  1. Technology, Safety and Costs of Decommissioning Nuclear Reactors At Multiple-Reactor Stations

    Energy Technology Data Exchange (ETDEWEB)

    Wittenbrock, N. G.

    1982-01-01

    Safety and cost information is developed for the conceptual decommissioning of large (1175-MWe) pressurized water reactors (PWRs) and large (1155-MWe) boiling water reactors {BWRs) at multiple-reactor stations. Three decommissioning alternatives are studied: DECON (immediate decontamination), SAFSTOR (safe storage followed by deferred decontamination), and ENTOMB (entombment). Safety and costs of decommissioning are estimated by determining the impact of probable features of multiple-reactor-station operation that are considered to be unavailable at a single-reactor station, and applying these estimated impacts to the decommissioning costs and radiation doses estimated in previous PWR and BWR decommissioning studies. The multiple-reactor-station features analyzed are: the use of interim onsite nuclear waste storage with later removal to an offsite nuclear waste disposal facility, the use of permanent onsite nuclear waste disposal, the dedication of the site to nuclear power generation, and the provision of centralized services. Five scenarios for decommissioning reactors at a multiple-reactor station are investigated. The number of reactors on a site is assumed to be either four or ten; nuclear waste disposal is varied between immediate offsite disposal, interim onsite storage, and immediate onsite disposal. It is assumed that the decommissioned reactors are not replaced in one scenario but are replaced in the other scenarios. Centralized service facilities are provided in two scenarios but are not provided in the other three. Decommissioning of a PWR or a BWR at a multiple-reactor station probably will be less costly and result in lower radiation doses than decommissioning an identical reactor at a single-reactor station. Regardless of whether the light water reactor being decommissioned is at a single- or multiple-reactor station: • the estimated occupational radiation dose for decommissioning an LWR is lowest for SAFSTOR and highest for DECON • the estimated

  2. Nuclear disposal with the example of a research reactor

    International Nuclear Information System (INIS)

    Organising a workshop on the subject of 'Nuclear disposal with the example of a research reactor' is a courageous undertaking in a time of intense political discussion on the authorisation for the research reactor at the Berlin Hahn-Meitner Institute, but on the other hand, it contributes to making the discussion more objective, based on scientific expertise. The contributions to the discussion regard the problem of nuclear disposal as differentiated from the legal, political and scientific points of way. It is proved that the disposal from research reactors must be part of an overall disposal concept in the Federal German Republic, but simultaneously has specific features which should be distinguished from more general nuclear energy electricity generation and nuclear disposal. (BBR)

  3. Spent nuclear fuel discharges from US reactors 1993

    Energy Technology Data Exchange (ETDEWEB)

    1995-02-01

    The Energy Information Administration (EIA) of the U.S. Department of Energy (DOE) administers the Nuclear Fuel Data Survey, Form RW-859. This form is used to collect data on fuel assemblies irradiated at commercial nuclear reactors operating in the United States, and the current inventories and storage capacities of those reactors. These data are important to the design and operation of the equipment and facilities that DOE will use for the future acceptance, transportation, and disposal of spent fuels. The data collected and presented identifies trends in burnup, enrichment, and spent nuclear fuel discharged form commercial light-water reactor as of December 31, 1993. The document covers not only spent nuclear fuel discharges; but also site capacities and inventories; canisters and nonfuel components; and assembly type characteristics.

  4. SNIF: A Futuristic Neutrino Probe for Undeclared Nuclear Fission Reactors

    CERN Document Server

    Lasserre, Thierry; Mention, Guillaume; Reboulleau, Romain; Cribier, Michel; Letourneau, Alain; Lhuillier, David

    2010-01-01

    Today reactor neutrino experiments are at the cutting edge of fundamental research in particle physics. Understanding the neutrino is far from complete, but thanks to the impressive progress in this field over the last 15 years, a few research groups are seriously considering that neutrinos could be useful for society. The International Atomic Energy Agency (IAEA) works with its Member States to promote safe, secure and peaceful nuclear technologies. In a context of international tension and nuclear renaissance, neutrino detectors could help IAEA to enforce the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). In this article we discuss a futuristic neutrino application to detect and localize an undeclared nuclear reactor from across borders. The SNIF (Secret Neutrino Interactions Finder) concept proposes to use a few hundred thousand tons neutrino detectors to unveil clandestine fission reactors. Beyond previous studies we provide estimates of all known background sources as a function of the detecto...

  5. Results of a monitoring programme in the environs of Berkeley aimed at collecting Chernobyl data for foodchain model validation

    International Nuclear Information System (INIS)

    The results of a fallout measurement programme which was carried out in the environs of Berkeley Nuclear Laboratory in the United Kingdom following the Chernobyl reactor accident in April 1986 are presented in this report. The programme was aimed at establishing a time-dependent data base of concentrations of Chernobyl fallout radionuclides in selected agricultural products. Results were obtained for milk, grass, silage, soil and wheat over an eighteen month period from May 1986. It is intended to use the data to validate the CEGB's dynamic foodchain model, which is incorporated in the FOODWEB module of the NECTAR environmental code. (author)

  6. Congenital malformations and infant mortality from the Chernobyl reactor accident; Angeborene Fehlbildungen und Saeuglingssterblichkeit nach dem Reaktorunfall in Tschernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Schoetzau, A.; Santen, F. van; Irl, C.; Grosche, B.

    1994-12-01

    The health impact of radiological contamination in Bavaria from the Chernobyl accident was evaluated. According to caesium 137 levels in soil samples, Bavaria was subdivided in a higher contaminated region (Southern Bavaria) and a lower contaminated region (Northern Bavaria). Indicators for health effects were congenital malformations, perinatal mortality, and infant mortality. Definition of the study periods accounted for the temporal relationship between conception as well as organogenesis and the time of highest exposure to radioactivity during the first weeks of May 1986. Statistical analysis was based on a combined spatial and temporal comparison. The results of the study do not show a significant increase in any of the outcome variables. Consequently, this study provides no evidence that radiation from Chernobyl caused a rise in the birth prevalence of congenital malformations or perinatal and infant mortality in the Bavarian population. (orig.) [Deutsch] Der vorliegende Bericht beschaeftigt sich mit den Folgen der Strahlenexposition in Bayern nach dem Reaktorunfall in Tschernobyl. Es wurde der Frage nachgegangen, ob eine Zunahme negativer gesundheitlicher Wirkungen in hoeher exponierten Bevoelkerungsgruppen im Vergleich zu niedriger exponierten feststellbar war. Der Expositionsstatus wurde nach der Bodenkontamination des Wohnortes bestimmt. Entsprechend der unterschiedlichen Hoehe des Radiocaesium-Gehaltes in Bodenproben wurde die Bevoelkerung der drei suedlichen bayerischen Regierungsbezirke `Oberbayern`, `Niederbayern` und `Schwaben` (Suedbayern) als hoeher und die Bevoelkerung der vier noerdlichen Regierungsbezirke `Oberpfalz`, `Oberfanken`, `Mittelfranken` und `Unterfranken` (Nordbayern) als niedriger exponiert definiert. Als Indikatoren fuer gesundheitliche Wirkungen wurden Veraenderungen der Geburtspraevalenz von Kindern mit ausgewaehlten angeborenen Fehlbildungen sowie Veraenderungen in den Raten der perinatalen Mortalitaet und der Gesamtsterblichkeit

  7. Research nuclear reactor RA - Annual Report 1994

    International Nuclear Information System (INIS)

    Activities related to revitalisation of the RA reactor stared in 1986, were continued in 1991. A number of interventions on the reactor components were finished that are supposed to enable continuous and reliable operation. The last, and at the same time largest action, related to exchange of complete reactor instrumentation is underway, but it is behind the schedule in 1991 because the delivery of components from USSR is late. Production of this instruments is financed by the IAEA according to the contract signed in December 1988 with Russian Atomenergoexport. According to this contract, it has been planned that the RA reactor instrumentation should be delivered to the Vinca Institute by the end of 1990. Only 56% of the instrumentation was delivered until September 1991. Since then any delivery of components to Yugoslavia was stopped because of the temporary embargo imposed by the IAEA. In 1991 most of the existing RA reactor instrumentation was dismantled, only the part needed for basic measurements when reactor is not operated, was maintained. Activities related to improvement of Russian project were continued in 1994. Control and maintenance of the reactor components was done regularly and efficiently. Extensive repair of the secondary coolant loop is almost finished and will be completed in the first part of 1995 according to existing legal procedures and IAEA recommendations. Fuel inspection by the IAEA safeguards inspectors was done on a monthly basis. There have been on the average 47 employees at the RA reactor which is considered sufficient for maintenance and repair conditions. Research reactor RA Annual report for year 1991 is divided into two main parts to cover: (1) operation and maintenance and (2) activities related to radiation protection

  8. Designing a mini subcritical nuclear reactor; Diseno de un mini reactor nuclear subcritico

    Energy Technology Data Exchange (ETDEWEB)

    Escobedo G, C. R.; Vega C, H. R.; Davila H, V. M., E-mail: rafelaescobedo@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Jardin Juarez 147, Col. Centro, 98000 Zacatecas, Zac. (Mexico)

    2015-10-15

    In this work the design of a mini subcritical nuclear reactor formed by means of light water moderator, uranium as fuel, and isotopic neutron source of {sup 239}PuBe was carried out. The design was done by Monte Carlo methods with the code MCNP5 in which uranium was modeled in an array of concentric holes cylinders of 8.5, 14.5, 20.5, 26.5, 32.5 cm of internal radius and 3 cm of thickness, 36 cm of height. Different models were made from a single fuel cylinder (natural uranium) to five. The neutron source of {sup 239}PuBe was situated in the center of the mini reactor; in each arrangement was used water as moderator. Cross sections libraries Endf/Vi were used and the number of stories was large enough to ensure less uncertainty than 3%. For each case the effective multiplication factor k{sub e}-f{sub f}, the amplification factor and the power was calculated. Outside the mini reactor the ambient dose equivalent H (10) was calculated for different cases. The value of k{sub eff}, the amplification factor and power are directly related to the number of cylinders of uranium as fuel. Although the average energy of the neutrons {sup 239}PuBe is between 4.5 and 5 MeV in the case of the mini reactor for a cylinder, in the neutron spectrum the presence of thermal neutrons does not exist, so that produced fissions are generated with fast neutrons, and in designs of two and three rings the neutron spectra shows the presence of thermal neutrons, however the fissions are being generated with fast neutrons. Finally in the four and five cases the amount of moderator is enough to thermalized the neutrons and thereby produce the fission. The maximum value for k{sub eff} was 0.82; this value is very close to the assembly of Universidad Autonoma de Zacatecas generating a k{sub eff} of 0.86. According to the safety and radiation protection standards for the design of mini reactor of one, two and three cylinders they comply with the established safety, while designs of four and five

  9. Startup control of the TOPAZ-II space nuclear reactor

    OpenAIRE

    Astrin, Cal D.

    1996-01-01

    Approved for public release; distribution isunlimited. The Russian designed and manufactured TOPAZ-II Thermionic Nuclear Space Reactor has been supplied to the Ballistic Missile Defense Organization for study as part of the TOPAZ International Program. A Preliminary Nuclear Safety Assessment investigated the readiness to use the TOPAZ-II in support of a Nuclear Electric Propulsion Space Test Mission (NEPSTP). Among the anticipated system modifications required for launching the TOPAZ-II sy...

  10. Multiscale Methods for Nuclear Reactor Analysis

    Science.gov (United States)

    Collins, Benjamin S.

    The ability to accurately predict local pin powers in nuclear reactors is necessary to understand the mechanisms that cause fuel pin failure during steady state and transient operation. In the research presented here, methods are developed to improve the local solution using high order methods with boundary conditions from a low order global solution. Several different core configurations were tested to determine the improvement in the local pin powers compared to the standard techniques, that use diffusion theory and pin power reconstruction (PPR). Two different multiscale methods were developed and analyzed; the post-refinement multiscale method and the embedded multiscale method. The post-refinement multiscale methods use the global solution to determine boundary conditions for the local solution. The local solution is solved using either a fixed boundary source or an albedo boundary condition; this solution is "post-refinement" and thus has no impact on the global solution. The embedded multiscale method allows the local solver to change the global solution to provide an improved global and local solution. The post-refinement multiscale method is assessed using three core designs. When the local solution has more energy groups, the fixed source method has some difficulties near the interface: however the albedo method works well for all cases. In order to remedy the issue with boundary condition errors for the fixed source method, a buffer region is used to act as a filter, which decreases the sensitivity of the solution to the boundary condition. Both the albedo and fixed source methods benefit from the use of a buffer region. Unlike the post-refinement method, the embedded multiscale method alters the global solution. The ability to change the global solution allows for refinement in areas where the errors in the few group nodal diffusion are typically large. The embedded method is shown to improve the global solution when it is applied to a MOX/LEU assembly

  11. Mesh generation technology for nuclear reactor simulation; barriers and opportunities

    International Nuclear Information System (INIS)

    Mesh generation in support of nuclear reactor simulation has much in common with the requirements of other application areas, such as computational fluid dynamics (CFD). Indeed, fluid dynamics analysis of the coolant behavior inside the reactor core is an internal flow problem that requires the resolution of spatial and temporal variations in the flow caused by complex component configurations, fluids/structure interaction, turbulence, and thermal heating of the coolant. Typical concerns of meshing complex geometries; the use of hexahedral vs. tetrahedral elements, element geometric quality, mesh smoothness, use of anisotropic elements in the thermal boundary layer, etc., are all considerations important to the reactor meshing problem. Reactor meshing begins to become more specialized as the need to employ reactor simulation as a predictive design and safety analysis capability grows in importance. First, a predictive capability will require more precise physical models to be included, and these models will need to be supported by a computational science framework that will allow them to be accurately approximated both spatially and temporally during the reactor core analysis. Both the multiphysical nature of the composite reactor model and details of the physics algorithms themselves will place new requirements on the meshing process needed to support multidimensional reactor simulation. This article discusses the current state of meshing technology applied to reactor simulation and examines a set of issues that are important in the generation of high-quality reactor meshes today and in the future

  12. Computer utilization for improvement of safety of nuclear reactors

    International Nuclear Information System (INIS)

    The development of instruction system for reducing the burden of operators and improving the reliability of nuclear power stations, the development of core operation and management system for BWRs and the method of adapting the analysis model for core characteristics to core conditions, the development of reactor management system for monitoring and forecasting core conditions in detail, the multi-function simulation system for nuclear power plants for analyzing plant characteristics and verifying the effectiveness of new systems, the examination of FBR operation and monitoring system using generalized model reference method, the development of forecasting system for environmental radioactivity and exposure dose in emergency, the backup computer system in Musashi Institute of Technology reactor using perfectly equal multi-processor system, the present status of on-line computer system for Kyoto University reactor for the research on computer control of a nuclear reactor, on-line and off-line data collection and analysis of operation characteristics of Kinki University reactor, renewal of measurement and control system for Rikkyo reactor, and the present status of change to on-line measurement and control of University of Tokyo reactor are reported. (Kako, I.)

  13. Modular reactor strategy as new-generation nuclear power

    International Nuclear Information System (INIS)

    Nuclear industries of the U.S. have been plaqued by serious loss of new orders due to the disturbed construction schedule, the uncertainty of public requirement, etc. It is in the midst of this gloomy environment that the modular reactor strategy emerged out in the U.S. as a new step toward recovering self-supporting nuclear industries. Given the clear incentive to revitalize the sluggish nuclear industries, their modular reactor approach is intended to create trouble-less, low management-risk reactors. Their major goals seem to be a low management risk, suitability for export, and shortened construction schedule. Modular reactors appear to have many advantages over large reactors that can apply not only to the U.S. but to Japan as well, serving for improvement of manufactures' productivity, significant saving of engineering costs, design simplification, reduction of licensing procedures and plant site work, improvement of plant availability, high export potential, significant reduction of total learning costs, expanded selection of plant sites, market-proximate and dispersed siting, reasonable reduction of required isolation distance, and creation of competitive environs. In Japan, most of the R and D items scheduled for the next decade are geared towards large reactors. The advantages of modular reactors, however, would be far-reaching even in Japan, and it would be desirable that their design details and characteristics be evaluated immediately, based on which appropriate follow-on activities should be initiated. (Nogami, K.)

  14. Research reactor activities in support of national nuclear programmes

    International Nuclear Information System (INIS)

    This report is the result of an IAEA Technical Committee Meeting on Research Reactor Activities in Support of National Nuclear Programmes held in Budapest, Hungary during 10-13 December 1985. The countries represented were Belgium, Finland, France, Federal Republic of Germany, German Democratic Republic, India, Poland, Spain, United Kingdom, United States, Yugoslavia and Hungary. The purpose of the meeting was to present information and details of several well-utilized research reactors and to discuss their contribution to national nuclear programmes. A related Agency activity, a Seminar on Applied Research and Service Activities for Research Reactor Operations was held in Copenhagen, Denmark during 9-13 September 1985. Selected papers from this Seminar relevant to the topic of research reactor support of national nuclear programmes have been included in this report. A separate abstract was prepared for each of 19 papers presented at the Technical Committee Meeting on Research Reactor Activities in Support of National Nuclear Programmes and for each of 15 papers selected from the presentations of the Seminar on Applied Research and Service Activities for Research Reactor Operations

  15. Research nuclear reactor RA - Annual report 1992

    International Nuclear Information System (INIS)

    Research reactor RA Annual report for year 1992 is divided into two main parts to cover: (1) operation and maintenance and (2) activities related to radiation protection. First part includes 8 annexes describing reactor operation, activities of services for maintenance of reactor components and instrumentation, financial report and staffing. Second annex B is a paper by Z. Vukadin 'Recurrence formulas for evaluating expansion series of depletion functions' published in 'Kerntechnik' 56, (1991) No.6 (INIS record no. 23024136. Second part of the report is devoted to radiation protection issues and contains 4 annexes with data about radiation control of the working environment and reactor environment, description of decontamination activities, collection of radioactive wastes, and meteorology data

  16. Diastolic left ventricular function in patients with mild and moderate hypertension - liquidators of the Chernobyl Nuclear Power Station accident

    International Nuclear Information System (INIS)

    Diastolic left ventricular function was studied by doppler-echocardiography in 25 healthy persons (control group) and 50 patients with mild and moderate hypertension including 28 liquidators of the Chernobyl accident consequences. Patients with hypertension including liquidators had such manifestations of diastolic left ventricular dysfunction. These manifestations were more pronounced in liquidators who also had greater left ventricular myocardial mass

  17. Reviewing ecosystems affected by the fallout from the Chernobyl reactor accident with respect to the resulting population exposure

    International Nuclear Information System (INIS)

    The research project is intended to yield information on the current radiological situation resulting from the Chernobyl fallout. Environmental materials of particular interest are game, mushrooms, berries, and forest stands in the most heavily affected forest ecosystem of the Bavarian forest area called Bayerischer Wald. This area has been intensively monitored in the period from 1988 until 1994, so that the development up to the current radiological situation can be analysed. Activities under the research project will encompass: Measurement of the radioactive contamination of specimens of the game population in the Bodenmais forest area of 7 500 hectares. Measurement of seasonal variations of the radiocesium activity in various indicator plants of the food chain of the game population. Soil sampling and radioactivity measurement at 2 cm depth intervals. The measuring work will be carried out in two areas which have been earmarked for monitoring over the last eight years (B1 and B2). The measured results will be compared with earlier data, and long-term space and time-dependent information on the transfer of radiocesium in the forest ecosystem under review will be derived. (orig./CB)

  18. Research nuclear reactor RA - Annual Report 1991

    International Nuclear Information System (INIS)

    Activities related to revitalisation of the RA reactor stared in 1986, were continued in 1991. A number of interventions on the reactor components were finished that are supposed to enable continuous and reliable operation. The last, and at the same time largest action, related to exchange of complete reactor instrumentation is underway, but it is behind the schedule in 1991 because the delivery of components from USSR is late. Production of this instruments is financed by the IAEA according to the contract signed in December 1988 with Russian Atomenergoexport. According to this contract, it has been planned that the RA reactor instrumentation should be delivered to the Vinca Institute by the end of 1990. Only 56% of the instrumentation was delivered until September 1991. Since then any delivery of components to Yugoslavia was stopped because of the temporary embargo imposed by the IAEA. In 1991 most of the existing RA reactor instrumentation was dismantled, only the part needed for basic measurements when reactor is not operated, was maintained. Construction of some support elements is almost finished by the local staff. The Institute has undertaken this activity in order to speed up the ending of the project. If all the planned instrumentation would not arrive until the end of March 1992, it would not be possible to start the RA reactor testing operation in the first part of 1993, as previously planned. In 1991, 53 staff members took part in the activities during 1991, which is considered sufficient for maintenance and repair conditions. Research reactor RA Annual report for year 1991 is divided into two main parts to cover: (1) operation and maintenance and (2) activities related to radiation protection

  19. Survey of methods and measurements of nuclear reactor time and frequency responses

    International Nuclear Information System (INIS)

    Methods of measuring reactivity effects in nuclear reactors are described and the main control engineering analytical problems in nuclear reactors are detailed. A description of the use of reactor models and adaptive control in improving the economy of power producing nuclear reactors is included. (author)

  20. REACTOR PHYSICS MODELING OF SPENT RESEARCH REACTOR FUEL FOR TECHNICAL NUCLEAR FORENSICS

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, T.; Beals, D.; Sternat, M.

    2011-07-18

    Technical nuclear forensics (TNF) refers to the collection, analysis and evaluation of pre- and post-detonation radiological or nuclear materials, devices, and/or debris. TNF is an integral component, complementing traditional forensics and investigative work, to help enable the attribution of discovered radiological or nuclear material. Research is needed to improve the capabilities of TNF. One research area of interest is determining the isotopic signatures of research reactors. Research reactors are a potential source of both radiological and nuclear material. Research reactors are often the least safeguarded type of reactor; they vary greatly in size, fuel type, enrichment, power, and burn-up. Many research reactors are fueled with highly-enriched uranium (HEU), up to {approx}93% {sup 235}U, which could potentially be used as weapons material. All of them have significant amounts of radiological material with which a radioactive dispersal device (RDD) could be built. Therefore, the ability to attribute if material originated from or was produced in a specific research reactor is an important tool in providing for the security of the United States. Currently there are approximately 237 operating research reactors worldwide, another 12 are in temporary shutdown and 224 research reactors are reported as shut down. Little is currently known about the isotopic signatures of spent research reactor fuel. An effort is underway at Savannah River National Laboratory (SRNL) to analyze spent research reactor fuel to determine these signatures. Computer models, using reactor physics codes, are being compared to the measured analytes in the spent fuel. This allows for improving the reactor physics codes in modeling research reactors for the purpose of nuclear forensics. Currently the Oak Ridge Research reactor (ORR) is being modeled and fuel samples are being analyzed for comparison. Samples of an ORR spent fuel assembly were taken by SRNL for analytical and radiochemical