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Sample records for 141ce 144ce dlya

  1. A new 144Ce/144Pr radioisotope generator system

    A miniaturized generator system was developed containing manganese dioxide-coated alumina on which 144Ce is deposited and from which 144Pr is eluted with an aqueous solution of 1% KIO3 in 1 N nitric acid. More than 60% of the 144Pr was recovered with a 99.9% radionuclide purity even after 2000 ml eluant and 1000 1 or air had been passed through the column. (author)

  2. Chromatographic isolation of 144Ce and 144Pr from the wastes of irradiated uranium treatment

    A two-step chromatographic technique was elaborated to isolate 144Ce, 144Pr from a solution of uranium fission products in 6M HNO3. The oxidation to Ce(III) by bromate and selective adsorption of 144Ce(IV) on anion exchange column were used to concentrate and purify 144Ce. Some impurities of uranium, 95Zr, 95Nb, 106Ru remain in 144Ce solution after the first step of its isolation. The final purification is achieved by passing the 6M HNO3 solution of 144Ce(IV) through the HDEHP-coated teflon column. The decontamination factors of 144Ce from main fission products are given. 7.2 mCi of (144Ce+144Pr) are recovered from each gram of irradiated uranium trioxide with the yield greater than 99%. An improvement of known generator was carried out to elute a purer 144Pr from maternal 144Ce(IV) adsorbed on the anion exchange column. (author)

  3. Toxicity of 144Ce inhaled in a relatively insoluble form by immature beagle dogs. VI

    Immature Beagle dogs (approximately equal to 3 months of age at exposure) have been exposed by inhalation to a relatively insoluble form of 144Ce (in fused aluminosilicate particles) to compare the resulting patterns of metabolism, dosimetry and biological effects with those seen in dogs exposed at 12 and 14 months of age and at 8 to 10.5 years of age. Five blocks of longevity animals, each consisting of 10 exposed dogs and one control, are currently on experiment. The initial lung burdens of the 144Ce-exposed dogs range from 0.004 to 140 μCi 144Ce/kg body weight. Three dogs with initial lung burdens of 73 to 120 μCi 144Ce/kg body weight died at 66 to 121 days after exposure with pulmonary injury and congestive heart failure. One dog with an initial lung burden of 140 μCi 144Ce/kg body weight died at 91 days after exposure with severe radiation pneumonitis and minimal pulmonary fibrosis and another dog whose initial lung burden was 70 μCi 144Ce/kg body weight died at 511 days after exposure with pulmonary injury that was mainly fibrotic in nature. Two dogs with initial lung burdens of 52 and 64 μCi 144Ce/kg body weight had primary pulmonary hemangiosarcomas and died at 618 and 689 days, respectively, with cumulative average absorbed beta doses to lung of 23,000 and 29,000 rads. One dog with an initial lung burden of 28 μCi 144Ce/kg body weight was euthanized at 1227 days after exposure with a hemangiosarcoma of the mediastinum, and another dog with an initial lung burden of 12 μCi 144Ce/kg body weight died at 1520 days after exposure from epilepsy. Serial observations are continuing on the surviving 40 exposed and five control dogs

  4. Toxicity of 144Ce inhaled in a relatively insoluble form by immature Beagle dogs. XVII

    Immature Beagle dogs (3-mo old) received a single, brief inhalation exposure to 144Ce in fused aluminosilicate particles as part of a series of studies designed to study the effects of age on dose response relationships for inhaled radionuclides. Forty-nine dogs inhaled graded levels of 144Ce that resulted in initial lung burdens ranging from 0.004-140 μCi/kg 0.15-5200 kBq/kg) body weight. Five control dogs inhaled nonradioactive fused aluminosilicate particles. Forty-one of the 144Ce-exposed dogs have died: 11 with lung tumors 4 with tumors of the tracheobronchial lymph nodes, with a nasal cavity tumor, and 9 with non neoplastic diseases of the respiratory tract. Observations are continuing on the 8 144Ce-exposed dogs that are surviving at this time. (author)

  5. Toxicity of inhaled 144CeCl3 in beagle dogs. VIII

    Studies on the metabolism, dosimetry, and effects of inhaled 144CeCl3 in the Beagle dog are continuing to provide information that will aid in assessing the biological consequences of inhaling 144Ce such as might be released in certain nuclear accidents. Studies on the tissue distribution of inhaled 144CeCl3 have shown that the 144Ce deposited in lung is translocated at a moderately rapid rate to liver and skeleton and that significant radiation doses are accumulated by all three organs. Fifty-five dogs that inhaled 144CeCl3 and 15 control dogs were placed in a longevity study and are being observed for their lifespan. The 144Ce dogs had long-term retained burdens with values ranging from 20 to 2900 μCi. Thirty-one of the dogs exposed to 144CeCl3 have died; 8 at 21 to 44 days after inhalation with signs attributed to severe bone marrow damage and associated pancytopenia; 2 at 138 and 144 days with radiation pneumonitis; 3 at 309 to 874 days with hepatic necrosis; 1 at 510 days with marrow aplasia; 1 at 375 days with pulmonary fibrosis; and 16 at 799 to 3081 days, most with neoplasms or myeloproliferative disorders. In this last group, 1 dog had an osteosarcoma, 3 had squamous cell carcinomas of the maxilla, 2 of the latter also having primary pulmonary neoplasms, 5 had hemangiosarcomas of the liver, 1 had a hemangiosarcoma of the nasal cavity, 2 had myelogenous leukemia, 1 had myelofibrosis with myeloid metaplasia, 1 had spinal cord ependymomas, and 2 did not have neoplasms. One of these had severe myelomalacia and the other diffuse hepatic lipidosis with severe degeneration. Two controls died; 1 with a thyroid carcinoma and 1 with aspiration pneumonia. Serial observations are continuing on the 24 surviving 144CeCl3 dogs and 13 control dogs. (U.S.)

  6. Toxicity of inhaled 144CeCl3 in beagle dogs. XI

    Studies on the metabolism, dosimetry and effects of inhaled 144CeCl3 in Beagle dogs are being conducted to assess the biological consequences of inhaling 144Ce such as might be released in certain nuclear accidents. Studies on the organ distribution of inhaled 144CeCl3 have shown that the 144Ce deposited in the lung is translocated at a moderately rapid rate to liver and skeleton and that significant radiation doses are accumulated by all three organs. Fifty-five dogs that inhaled 144CeCl3 and 15 control dogs are being observed for their life span. The 144Ce dogs have long-term retained burdens with values ranging from 20 to 2900 μCi. Forty-five of the dogs exposed to 144CeCl3 have died; eight from 21 to 44 days after inhalation with severe bone marrow damage and associated pancytopenia; two at 138 and 144 days with radiation pneumonitis; three from 309 to 874 days with hepatic necrosis; one at 510 days with marrow aplasia; one at 375 days with pulmonary fibrosis; and 30 from 799 to 4085 days, most with neoplasms or myeloproliferative disorders. In this last group, one dog had an osteosarcoma, five had squamous cell carcinomas of the nasal cavity (two also having primary pulmonary neoplasms), six had hemangiosarcomas of the liver, one had a hemangiosarcoma of the nasal cavity, two had myelogenous leukemia, one had myelofibrosis with myeloid metaplasia, one had spinal cord ependymomas, one had a malignant melanoma (also an ependymoma) and two had mammary adenocarcinomas. Three dogs had primary pulmonary neoplasms including two with bronchogenic adenocarcinomas and one with an adenoma. Seven did not have malignant neoplasms. Two of these had severe myelomalacia, one had pulmonary edema, three had congestive heart failure and one had diffuse hepatic lipidosis with severe hepatic degeneration

  7. Toxicity of 144Ce inhaled in a relatively insoluble form by aged Beagle dogs. XII

    The toxicity of relatively insoluble 144Ce inhaled by 8- to 10.5-year-old Beagle dogs is being investigated to determine possible age-related differences in long-term biological responses. Forty-two dogs were exposed to aerosols of 144Ce in fused aluminosilicate particles to yield initial lung burdens of 2.2 to 75 μCi 144Ce/kg body weight, and 12 control dogs were exposed to non-radioactive fused aluminosilicate particles. All 144Ce-exposed and control dogs have died or were euthanized between 197 and 2726 days after the inhalation exposure. Prominent findings in the 144Ce-exposed dogs were radiation pneumonitis in 19 of the 23 dogs that died during the first 943 days after exposure, and neoplastic disease in 13 of the 20 dogs that died beyond 904 days after exposure. Pulmonary tumors were found in five of these dogs. In contrast to the study with young adult dogs, in which pulmonary hemangiosarcomas were one of the prominent findings, all of these tumors were carcinomas

  8. Toxicity of 144Ce inhaled in a relatively insoluble form by immature Beagle dogs. XII

    Immature Beagle dogs (3 months old) were exposed once by inhalation to an aerosol of 144Ce incorporated in fused aluminosilicate particles. The influence of this age on the dose-response relationships is being compared to that of 13-mo-old and 8 to 10.5-yr-old dogs. This study involves 49 dogs that received graded initial lung burdens from 0.004 to 140 μCi 144Ce/kg body weight and five control dogs. To date, 19 of the 144Ce-exposed dogs and one of the controls have died. Dogs with the highest initial lung burdens of 144Ce died during the first 4 months with radiation pneumonitis, pulmonary fibrosis, and congestive heart failure. Pulmonary hemangiosarcoma was the primary finding in dogs that died at 1.5 to 2 years after exposure. Deaths beyond that time have been due primarily to extrapulmonary hemangiosarcomas. Observations are continued on the surviving 30 144Ce-exposed and four control dogs at 7.0 to 11.2 years after exposure

  9. Toxicity of inhaled 144Ce in fused aluminosilicate particles in aged beagle dogs. V

    The toxicity of 144Ce in fused aluminosilicate particles inhaled by 8- to 10.5-yr-old dogs is being investigated to provide information on age-related differences in the response of older members of the human population to accidental inhalation of radioactive aerosols. These data on aged dogs will be compared to the results of similar studies of dogs exposed at approximately 3 mo or 12 to 14 mo of age. Six blocks of five female dogs each have been divided into four exposure levels with mean initial lung burdens of 7.2, 14, 28 and 57 μCi 144Ce/kg body weight. Six blocks of four male dogs have been divided into three exposure levels with mean initial lung burdens of 7.2, 14 and 28 μCi 144Ce/kg body weight. Controls in each block were exposed to fused aluminosilicate particles containing stable cerium. Fifteen dogs with initial lung burdens ranging from 20 to 75 μCi 144Ce/kg body weight and cumulative doses to lung of from 22,000 to 74,000 rads have died or were euthanized 197 to 1207 days after exposure with clinicopathologic findings of radiation pneumonitis and pulmonary fibrosis.Pulmonary retention of the inhaled 144Ce was similar to that observed previously in dogs exposed at 18 to 22 mo of age in a radiation dose pattern study. Serial observations are continuing on the 19 surviving 144Ce-exposed and eight control dogs

  10. Toxicity of 144Ce fused clay particles inhaled by aged dogs. III

    The toxicity of 144Ce fused clay particles inhaled by 8- to 10.5-year-old dogs is being investigated to provide information on age-related differences in the response of older members of the human population to accidental inhalation of radioactive aerosols. These data on aged dogs will be compared to the results of similar studies using dogs exposed at approximately 3 months or 12 to 14 months of age. To date, 7 blocks of 5 dogs each, divided into 4 exposure levels with mean initial lung burdens of 7.5, 14, 24, and 57 μCi/kg body weight and control dogs exposed to non-labeled fused clay particles have been entered into a longevity study. Twelve dogs with initial lung burdens ranging from 20 to 75 μCi 144Ce/kg body weight and cumulative doses to lung of from 22,000 to 74,000 rads have died at 197 to 943 days post-inhalation with clinico-pathologic findings of radiation pneumonitis and pulmonary fibrosis. Two of these also had congestive heart failure. In addition, 4 dogs with ILBs of 8 to 14 μCi 144Ce/kg body weight have died of mammary neoplasms or congestive heart failure but without radiation pneumonitis. One dog with an ILB of 9 μCi 144Ce/kg body weight died with a chronic interstitial foreign body pneumonia. Two control dogs have died, one with a mammary carcinoma and one with pyometra. Pulmonary retention of the inhaled 144Ce was similar to that observed previously in dogs exposed at 18 to 22 months of age in a radiation dose pattern study. Serial observations are continuing on the 11 surviving 144Ce-exposed dogs and 5 controls. (U.S.)

  11. Toxicity of 144Ce inhaled in a relatively insoluble form by immature Beagle dogs. VIII

    The influence of age at exposure on the resulting patterns of deposition, retention, dosimetry and biological effects from a single inhalation exposure to a relatively insoluble form of a beta-emitting radionuclide with a relatively long physical half-life is being investigated. Immature Beagle dogs (3 months of age) have been exposed once, by inhalation, to an aerosol of 144Ce incorporated in fused aluminosilicate particles. Eighteen of these dogs were serially sacrificed to study the patterns of deposition, retention and dosimetry and the remaining 49 dogs received graded initial lung burdens that ranged from 0.004 to 140 μCi 144Ce/kg body weight and are being observed over their life span for study of the resulting long-term biological effects. Five control dogs are also included in this study. To date, 13 of the 144Ce-exposed dogs in the longevity study and none of the controls have died. Dogs with the highest initial lung burdens of 144Ce died first (during the first 4 months) with radiation pneumonitis, pulmonary fibrosis and congestive heart failure. Pulmonary hemangiosarcoma was the primary finding in dogs that died at 1.5 to 2 years after exposure. Deaths beyond that time have primarily involved extrapulmonary hemangiosarcomas. One dog, 627B, with an initial lung burden of 24 μCi 144Ce/kg body weight died during the past year at 2341 days after exposure with a widely disseminated hemangiosarcoma showing heavy involvement of the liver and skin. Observations are continuing on the surviving 36 144Ce-exposed and five control dogs

  12. Toxicity of 144Ce inhaled in a relatively insoluble form by aged beagle dogs. VI

    The toxicity of 144Ce inhaled in fused aluminosilicate particles by 8 to 10.5-year-old dogs is being investigated to provide information on age-related differences in the response of older members of the human population to accidental inhalation of radioactive aerosols. These data on aged dogs will be compared to the results of similar studies of dogs exposed at approximately 3 months or 12 to 14 months of age. Six blocks of five female dogs each have been divided into four exposure levels with mean initial lung burdens of 7.2, 14, 28 and 57 μCi 144Ce/kg body weight. Six blocks of four male dogs each have been divided into three exposure levels with mean initial lung burdens of 7.2, 14 and 28 μCi 144Ce/kg body weight. Controls in each block were exposed to fused aluminosilicate particles containing stable cerium. Eighteen dogs with initial lung burdens ranging from 14 to 75 μCi 144Ce/kg body weight and cumulative doses to lung of from 22,000 to 74,000 rads have died or were euthanized 197 to 1207 days after exposure with clinicopathologic findings of radiation pneumonitis and pulmonary fibrosis

  13. Effect of 144Ce inhaled in fused clay particles on the tracheobronchial lymph nodes

    Tracheobronchial lymph node changes and lymphopenia are sequelae to inhalation of relatively insoluble radioactive aerosols by Beagle dogs. To assess the development of these lesions, tracheobronchial lymph nodes from dogs that inhaled 144Ce in fused clay particles were examined at intervals from 2 to 730 days after exposure. Initial lung burdens in the dogs studied ranged from 33 to 63 μCi/kg body weight. The concentration of radioisotope in the tracheobronchial lymph nodes increased during the first year after exposure and exceeded that in the lung about 100 days after exposure. Autoradiographs of the lymph nodes showed that 144Ce particles were present in macrophages in the paracortical zone two days after exposure and that concentrations continued to increase in the paracortical zone and medullary cords. Histologic changes in the nodes included atrophy of the germinal centers and lymphocytic follicles, loss of lymphocytes and accumulation of macrophages in the paracortical zone, accumulation of pigment and isotope-laden macrophages in the medullary cords, occasional infiltrates of neutrophils in the medullary cords and, at later time periods, focal fibrosis of the medullary cords. Tracheobronchial lymph node weights of the dogs exposed to 144Ce in fused clay were not decreased until 512 days after exposure. These findings indicate that tracheobronchial lymph nodes accumulate relatively high burdens of 144Ce after inhalation of 144Ce in a relatively insoluble form and that the pathologic changes resulting from these burdens are basically atrophic in nature. Primary neoplasms in lymph nodes have not been observed in dogs with initial lung burdens from 0.0024 to over 30 μCi/kg body weight followed for up to 2000 days post-exposure. At the higher levels, however, a high incidence of primary pulmonary neoplasia has been observed. (U.S.)

  14. Toxicity of 144Ce inhaled in a relatively insoluble form by immature Beagle dogs. VII

    Immature Beagle dogs (approx. = 3 months of age at exposure) have been exposed by inhalation to a relatively insoluble form of 144Ce (in fused aluminosilicate particles) to compare the resulting patterns of metabolism, dosimetry and biological effects with those seen in dogs exposed at 12 and 14 months of age and at 8 to 10.5 years of age. Five blocks of longevity animals, each consisting of 10 exposed dogs and one control, are currently being studied. The initial lung burdens of the 144Ce-exposed dogs range from 0.004 to 140 μCi 144Ce/kg body weight. Three dogs with initial lung burdens of 73 to 120 μCi 144Ce/kg body weight died at 66 to 121 days after exposure with pulmonary injury and congestive heart failure. One dog with an initial lung burden of 140 μCi 144Ce/kg body weight died at 91 days after exposure with severe radiation pneumonitis and minimal pulmonary fibrosis and another dog whose initial lung burden was 70 μCi 144Ce/kg body weight died at 511 days after exposure with pulmonary injury that was mainly fibrotic in nature. Four dogs with initial lung burdens of 52 to 79 μCi/kg body weight had primary pulmonary hemangiosarcomas and died between 618 and 738 days, with cumulative average absorbed beta doses to lung of 23,000 to 31,000 rads. Two of these dogs, 1027S and 1024D, died within the past year. One dog with an initial lung burden of 28 μCi/kg body weight was euthanized at 1227 days after exposure with an hemangiosarcoma of the mediastinum. Within the past year, Dog 627S, with an initial lung burden of 48 μCi/kg body weight, died 1732 days after exposure with hemangiosarcoma primary in the liver or spleen. A dog with an initial lung burden of 12 μCi/kg body weight died from epilepsy at 1520 days after exposure. Serial observations are continuing on the surviving 37 exposed and five control dogs

  15. Toxicity of inhaled 144Ce fused clay particles in beagle dogs. VII

    The metabolism, dosimetry, and effects of inhaled 144Ce in fused clay particles are being investigated in the Beagle dog to aid in assessing the biological consequences of release of 144Ce in a relatively insoluble form such as might occur in certain types of nuclear accidents. The toxicity of inhaled 144Ce fused clay is also of general interest since it is representative of intermediate-lived beta-emitting radionuclides. Two major studies with young adult dogs (12 to 14 months of age at exposure) are involved: (1) a metabolism and dosimetry study in which 24 dogs were serially sacrificed over an extended period of time, and (2) a longevity study with 2 series of dogs; Series I with 15 dogs exposed to aerosols of 144Ce in fused clay particles to yield initial lung burdens of 11 to 210 μCi/kg body weight and 3 control dogs exposed to nonradioactive fused clay particles and Series II with 96 dogs exposed to aerosols of 144Ce in fused clay particles to yield initial lung burdens of 0.0024 to 66 μCi/kg body weight and 12 control dogs exposed to nonradioactive fused clay particles. Twenty-eight dogs died or were euthanized at 143 to 2396 days after inhalation of 144Ce. The prominent findings were radiation pneumonitis in 17 dogs that died or were euthanized at early time periods and neoplastic disease in 10 of the 11 dogs that died or were euthanized at 750 days or later; 5 with hemangiosarcoma of the lung, 1 with both a hemangiosarcoma and a fibrosarcoma of the lung, 1 with both a bronchiolo-alveolar carcinoma and a hemangiosarcoma of lung, 1 with a hemangiosarcoma of lung, bronchiolo-alveolar carcinoma, and a bronchiogenic adenocarcinoma, and 1 each with a hemangiosarcoma of the mediastinum and of the spleen. The cumulative radiation dose to the lung at time of death has ranged from 22,000 to 140,000 rads. Serial observations are continuing on the 83 survivors and 15 controls. (U.S.)

  16. Extraction of carrier-free 144Ce with acetylacetone and 8-hydroxyquinoline

    The extraction of carrier-free 144Ce with 3.25 to 0.65 M solutions of acetylacetone in carbon tetrachloride and with 1.0 to 0.01 M solutions of 8-hydroxyquinoline in chloroform at a constant as well as variable pH was investigated. On the basis of the analysis of distribution curves it may be presumed that in both extraction systems the oxidation of cerium(III) to cerium(IV) microamounts takes place. The distribution curves of extraction and reextraction in the systems with 8-hydroxyquinoline show a considerable complexity. In the extraction system with acetylacetone constants were found which satisfactorily express the distribution of 144Ce in this system. (author)

  17. Biological effects of repeated exposure of beagle dogs to relatively insoluble aerosols of 144Ce. IV

    This experiment is being conducted to study the behavior and long-term biological effects in Beagle dogs of 144Ce inhaled in fused aluminosilicate particles in repeated inhalation exposures for comparison with similar data from dogs that were exposed only once to a similar aerosol. Four groups of nine dogs each were exposed once every eight weeks for two years (13 exposures) to achieve specified exposure goals. The 144Ce-exposed dogs received increasing or relatively constant beta radiation dose rates in contrast to the steadily decreasing dose rate seen after a single inhalation exposure. Exposures in the first and second groups were planned to yield a cumulative absorbed dose to lung of approximately equal to 35,000 rads and those in the third group approximately equal to 17,000 rads within two years after the first exposure. Singly exposed dogs that had died with pulmonary tumors when this experiment was initiated had cumulative doses to death of 29,000 to 61,000 rads. All 13 exposures have been completed. One dog in the 4.5-μCi 144Ce/kg body weight group died at 771 days after first exposure with emaciation, adrenal cortical degeneration and bone marrow aplasia. One control dog died accidentally during anesthesia. During the past year, two additional dogs have died. One dog in the repeated 2.5-μCi 144Ce/kg body weight group died at 1256 days after the first exposure with radiation pneumonitis and pulmonary fibrosis and a control dog died at 1052 days with autoimmune hemolytic anemia. The remaining 32 dogs appear to be in good physical condition except for a persistent lymphopenia at approximately equal to 4 years after the first exposure. They are being maintained for life span observations

  18. The uptake of 90Sr, 137Cs and 144Ce by leaves of spring wheat and rape

    The distribution and accumulation of 90Sr, 137Cs, 144Ce through the leaf surface into the plant have been studied. The results show that the uptake rate of 137Cs by crop plant is about 53%, while the uptake rate for 90Sr and 144Ce is about 0.4%. However 90Sr is absorbed in significant amount from soil whereas 137Cs is absorbed in negligible amount

  19. Influence of chelation therapy (DTPA) on 141Ce retention in rats

    We investigated the influence of oral and parenteral administration of chelation therapy on the retention of 141Ce in young rats. Opposite to results obtained in adult rats present results show high efficacy of oral chelation therapy in reducing radiocerium retention in the whole body and organs of suckling rats. (author) 3 refs

  20. Liver tumors in Beagle dogs exposed by inhalation to 144CeCl3

    Primary malignant hepatic neoplasms developed in 9 of 55 Beagle dogs (16 percent) exposed to 144CeCl3 in CsCl aerosol (seven primary hepatic hemangiosarcomas, one hepatocellular carcinoma and one intrahepatic bile duct carcinoma). Cerium-144 was rapidly translocated from the lung to the liver and skeleton; the liver received the highest cumulative beta dose. The latent periods of hepatic hemangiosarcomas appeared to be dose-related; death from hepatic hemangiosarcoma occurred earlier in dogs which received higher beta doses

  1. Development of a phantom and assessment of (141)Ce as a surrogate radionuclide for flood field uniformity testing of gamma cameras.

    Saxena, Sanjay Kumar; Kumar, Yogendra; Malpani, Basant; Rakshit, Sutapa; Dash, Ashutosh

    2016-06-01

    This paper describes an indigenous method for development and deployment of rechargeable liquid filled phantom with newly proposed radionuclide (141)Ce for determination of extrinsic uniformity of gamma cameras. Details about design of phantom, neutron irradiation of cerium targets, chemical processing of (141)Ce, charging of phantom with (141)Ce solution and their performance evaluation are presented. Suitability of (141)Ce in quality assurance of gamma cameras used in in-vivo diagnostic imaging procedures has been amply demonstrated. PMID:27031297

  2. K-shell ionization in the beta decay of 141Ce

    The total K-shell ionization probability accompanying the β- decay of 141Ce to the 0.145-MeV level in 141Pr was determined to be (1.79 +- 0.11) x 10-4 from Pr Kα x rays in coincidence with the 0.145-MeV gamma ray. This result is in very good agreement with the theoretical calculations of Law and Suzuki

  3. Biological effects of repeated inhalation exposure of Beagle dogs to relatively insoluble aerosols of 144Ce. V

    The behavior and long-term biological effects in Beagle dogs of 144Ce inhaled in fused aluminosilicate particles in repeated inhalation exposures are being studied for comparison with data from dogs that were exposed only once to a similar aerosol. Four groups of nine dogs each were exposed once every 8 weeks for 2 years (13 exposures) to achieve specified exposure goals. These goals were: to increase the lung burden by 2.5 μCi 144Ce/kg body weight with each exposure in the first group; to reestablish lung burdens of 9 or 4.5 μCi 144Ce/kg body weight in the second and third groups, respectively; and to expose controls (fourth group) to fused aluminosilicate particles containing stable cerium. With these exposure sequences, the 144Ce-exposed dogs received increasing or relatively constant beta radiation dose rates in contrast to the steadily decreasing dose rate seen after a single inhalation exposure. Exposures in the first and second groups were planned to yield a cumulative absorbed dose to lung of approx. = 35,000 rads and those in the third group approx. = 17,000 rads within two years after the first exposure. All 13 exposures have been completed. During the past year, one dog in the 9.0 μCi 144Ce/kg body weight group died at 1558 days after the first exposure with autoimmune hemolytic anemia. The remaining 24 144Ce-exposed and seven control dogs generally appear to be in good physical condition with exception of a persistent lymphopenia at approx. = 5 years after the first exposure. They are continuing to be maintained for life span observations

  4. Effects of inhaled 144Ce on cardiopulmonary function and histopathology of the dog

    Twelve dogs inhaled single doses of relatively insoluble particles containing 144Ce and six dogs inhaled particles containing stable cerium as controls. Pulmonary function, clinical, and radiographic evaluations were performed serially. The dogs developed progressive radiation pneumonitis and pulmonary fibrosis similar to that previously reported for whole-lung irradiation from internal or external sources. Focal histologic changes in bronchioles and alveoli were detected functionally during treadmill and tube-breathing stresses at a time when the dogs' clinical and radiographic appearances were normal. Moderate functional impairment was associated with more severe inflammatory and proliferative changes in airways and alveoli. Severe impairment resulted from progressive fibrosis and scarring. These were several strong correlations between functional indices and histological scores. There was a nonlinear relationship between cumulative radiation dose and effects, and once the functional alterations became clinically evident, the disease progressed with little further increase in dose

  5. Biological effects of repeated inhalation exposure of beagle dogs to aerosols of 144Ce in fused clay particles I

    This experiment was initiated to study the biological behavior and long-term effects of repeated inhalation exposures to 144Ce in fused clay particles compared with those seen in Beagle dogs that received a single exposure as young adults. The 36 dogs, divided into four equal groups, are exposed every 8 weeks to achieve the following: to maintain lung burdens of 9 and 4.5 μCi 144Ce/kg body weight in the first and second groups, respectively; to increase the lung burden by 2.5 μCi 144Ce/kg body weight in the third group with each exposure and to expose controls (fourth group) to fused clay containing stable cerium. With these exposure sequences, the 144Ce-exposed dogs will receive increasing or maintained β dose rates in contrast to the steadily decreasing dose rate seen after a single inhalation exposure. Exposures to the first and third groups will produce a cumulative absorbed dose to lung of approximately equal to 35,000 rads and those to the second group will yield approximately equal to 17,000 rads within 2 yr after the first exposure. Single exposure dogs that had died with pulmonary neoplasia when this experiment was initiated had cumulative doses to death of 29,000 to 61,000 rads. Six of the planned 13 exposures have been completed to date. All exposed dogs are surviving and will be maintained for lifespan observation. (U.S.)

  6. Effect on canine lymphocyte function of 144Ce inhaled in fused clay particles

    Beagle dogs exposed by inhalation to 144Ce in fused clay particles develop a persistent lymphopenia and the remaining peripheral lymphocytes in these dogs show a depressed in vitro response to plant mitogens. These studies were designed to evaluate the cellular basis for this defect. The survival and growth of lymphocytes from irradiated and control dogs were evaluated through 96 hours of culture. Many irradiated lymphocytes that were viable in vivo died within 24 hours in vitro. The remaining lymphocytes appeared to grow normally indicating that the early in vitro death was responsible for at least a portion of the difference between irradiated and control lymphocyte cultures. A second experiment was designed to determine if any humoral factors in plasma of irradiated dogs were responsible for the poor response of the lymphocytes. Lymphocytes from irradiated and control dogs were grown with plasma from both types of animals. Heterologous plasma had no apparent effect on lymphocyte growth, indicating that humoral factors were not involved. (U.S.)

  7. Effect of fasting on the transit time of 144Ce in the mouse gut

    Our work with G.I. absorption of actinide elements indicates greater absorption by fasted animals than by animals on regular diets (Weiss and Walburg, undated). Residence time of a metallic compound in the gut may be an important factor influencing G.I. absorption. Cerium-144 (III) chloride was administered by gavage to fasted mice and to mice on regular feed. The G.I. tract was excised, cut into sections, and the activity of each section determined as a function of time after dosing. Our results indicate rapid transit of 144CeCl3 along the empty mouse gut. One hour after dosing, about half the Ce is in the cecal contents; about 40% remains in stomach contents. Twelve hours after dosing, only about 2% remains in the cecum; by 16 hours, almost the entire dose has been cleared from the intestine. Transit times in mice with stomach and intestines containing food were 12 hours longer than in fasted mice. These results lead to the conclusion that factors other than G.I. residence time determine G.I. absorption of actinides in mice

  8. Kinetic study of the deposition of 144Ce, 143Pr and 147Nd on a platinum anode

    Investigation of the electrodeposition of radioactive rare earth metal isotopes confirm that, depending on the conditions of electrolysis, they can be deposited on the platinum either cathodically or anodically. The anodic deposition of these isotopes can take place with electrochemical oxidation or electrosorption without electron-transfer, depending on the lanthanide(III-IV) oxidation potentials. The present paper reports the results of the investigation connected with the anodic deposition of 144Ce, 143Pr and 147Nd. (author)

  9. Biological effects of repeated inhalation exposure of Beagle dogs to relatively insoluble aerosols of 144Ce. VI

    Beagle dogs were exposed repeatedly to a relatively insoluble form of 144Ce (in fused aluminosilicate particles) to study the deposition, retention and long-term biological effects for comparison with data from dogs that were exposed only once to a similar aerosol. Four groups of nine dogs each were exposed once every 8 weeks for 2 years (13 exposures) to achieve specified exposure goals. These goals were: to increase the lung burden by 2.5 μCi 144Ce/kg body weight with each exposure; to reestablish lung burdens of 9 or 4.5 μCi 144Ce/kg body weight and to expose controls to fused aluminosilicate particles containing nonradioactive cerium. With these exposure sequences, the 144Ce-exposed dogs received increasing or relatively constant beta radiation dose rates in contrast to the steadily decreasing dose rate seen after a single inhalation exposure. Following completion of the exposure series, the dogs are being observed for the development of long-term biological effects. To date, 11 dogs have died or were euthanized, nine exposed dogs and two controls. Although pulmonary hemangiosarcomas were a prominent finding in dogs exposed once to the same aerosol at a level that led to cumulative doses to lung similar to these repeatedly exposed dogs, only one has been observed in the repeatedly exposed dogs. Other effects of note to date include three pulmonary carcinomas, two hemangiosarcomas of the tracheobronchial lymph nodes and one splenic hemangiosarcoma. Observations are continuing on the surviving 18 exposed and seven control dogs

  10. Use of 141Ce as a particulate digesta flow tracer in ruminants. II. Behavior of the tracer at the duodenum and in the feces

    A ration of 600 g chopped hay and 150 g ground sorghum is given twice daily to sheep fitted with a rumen cannula and a duodenal reentrant cannula. 141Ce flow rate at the duodenum and in the feces is compared to flow rate of stained hay particles after ingestion of a single labelled meal. After an adaptation period during which both daily meals are labelled, variations in 141Ce concentration are then measured in the duodenal and fecal dry matter. The tracer is used to estimate dry mater digestibility indirectly. Duodenal data show that the mean retention time of 141Ce in the rumen is about 15% less than that of stained particles. The meal after the radioactive one momentarily depresses 141Ce excretion rate while it accelerates that of the stained particles. Mean retention time in the whole gastro-intestinal tract of a meal of 600 g chopped hay 150 g ground sorghum is 40.4+-3.8 h or 32.4+-3.7 h, depending on whether stained particles or 141Ce is used. All the 141Ce ingested is recovered in the feces. Mean recovery of 141Ce in the feces excreted during 200 hours after dosage is 100.2+-5.0%. After a period of adaptation where all meals are radioactive, feces of 2 sheep are sampled either by total collection or directly in the rectum. Dry matter digestibility does not differ whether calculated from total collection or by the indirect method using 141Ce

  11. Decontamination of 60Co and 144Ce. low-activity liquid wastes with the Fe3+ /OH- /Ca2+ /PO-4-3- system

    The influence of reaction time, concentrations of Fe3+ and PO-4-3+, temperature and agitation velocity in the efficiency of decontamination of 60Co and 144Ce low-activity liquid wastes using the Fe3+ /OH-/Ca2+ /PO-4-3+ precipitator system was stud ied in this paper. The mathematical models of this process were obtained for 60Co and 144Ce. The best conditions for the decontamination we re calculated using the optimization program

  12. Biological alterations resulting from chronic lung irradiation. I. The pulmonary lipid composition, physiology, and pathology after inhalation by beagle dogs of 144Ce-labeled fused clay aerosols

    Three groups of four beagle dogs inhaled a 144Ce-labeled fused clay aerosol; two additional dogs per group, exposed to a stable cerium-labeled fused clay aerosol, were used as controls. At monthly intervals, one diaphragmatic lobe of each of two dogs exposed to 144Ce and one control animal from each group was lavaged with isotonic saline. The recovered lavage solutions were centrifuged to isolate lung cells (mostly macrophages) and surfactant for lipid analyses. The groups were sacrificed at 2, 4, and 6 mo after exposure, when the lungs of the dogs exposed to 144Ce had average cumulative radiation doses of 23, 36, and 59 krad, respectively. Chronic irradiation of the lung resulted in a progressive radiation pneumonitis which was assessed clinically and pathologically at various intervals. At sacrifice, the lungs were analyzed for 144Ce and the right apical and diaphragmatic lobes were minced and lyophilized and the lipids were extracted. Total lipids from all lung samples were determined gravimetrically and individual compounds were identified, isolated, and quantitated. The quantities of lipid in lung tissue, in pulmonary cells, and in surfactant increased as a function of time and radiation dose. Neutral lipids (sterol esters and triglycerides) accounted for most of the increase. (U.S.)

  13. Suppression of the pulmonary clearance of Staphylococcus aureus in mice that had inhaled either 144CeO2 or 239PuO2

    The rate of pulmonary clearance of inhaled Staphylococcus aureus in mice was determined at intervals after inhalation exposure to either 144CeO2 or 239PuO2. In mice with mean initial lung burdens between 0.6 and 4.7 μCi 144Ce the pulmonary clearance of S. aureus was suppressed up to 12 weeks after inhalation of 144CeO2. In mice with mean initial lung burdens between 1.3 and 29.0 μCi 239Pu the pulmonary clearance of S. aureus was suppressed up to 26 weeks after inhalation of 239PuO2. The suppressed pulmonary clearance of S. aureus appeared to correlate with the radiation dose rate to the lungs at the time of exposure to bacteria but not with the cumulative radiation dose to the lungs. The changes in bacterial clearance did not appear to be correlated with changes in body weight, hematological parameters, or radiation-induced histopathological changes. Altered bacterial clearance may be related to radiation damage to pulmonary macrophages. It was concluded that irradiation of the lung from radionuclides inhaled in relatively insoluble forms may result in increased bacterial invasion of the lungs

  14. Use of 141Ce as a particulate digesta flow tracer in ruminants. I. Determination of uptake on feed and behavior in rumen digesta in vivo

    The suitability of 141Ce as a particulate digesta flow tracer is studied in sheep. The amount and the factors of cerium uptake on feed particles by incubating alfalfa hay and sorghum seeds in water containing 141Ce in solution are determined. After soaking one hour, 80% radioactivity is retained on the hay 17% on the sorghum. Incubation time is the main factor determining uptake rate. This uptake is solid on the hay and more fragile on the sorghum. The evolution of 141Ce distribution among the different physical constituents of rumen digesta is studied on two sheep given a single radioactive meal (10μCi). These sheep are fitted with a rumen cannula and fed twice daily with hay (80%) and sorghum (20%). There is little 141Ce in solution in the supernatant liquid after centrifugation of digesta. At the end of the 'labelled' meal, specific radioactivity (RAS) of liquid-phase digesta, separated by filtering on two layers of gauze, is equal to or higher than the RAS of the solid phase. It increases up to the next unlabelled meal and then decreases. Microorganisms may cause this transfer of liquid-phase radioactivity to the large particles. Specific radioactivity of the microorganisms remains very high after the 'labelled' meal as compared to that of different granulometric fractions of solid digesta

  15. An experimental study of the time dependence of uptake from soil of 137Cs, 106Ru, 144Ce and 99Tc into green vegetables, wheat and potatoes

    In this study the experimental data were analysed using the CEGB's dynamic foodchain model, and were used to validate the relevant part of the model structure, to produce model-specific input data and to identify possible future improvements to the model structure. The root uptake of the specified radionuclides was studied and the concentration levels measured. The data were analysed using a simplified version of the general model. The compartment system incorporated within the model was shown to be capable of reproducing the data for 137Cs, 106Ru and 144Ce to an extent sufficient to justify its use in ingestion radiological dose assessments, but to be less successful in fitting the 99Tc data. The analysis resulted in the production of a well validated set of model-specific input data relevant to UK conditions and agricultural practice differing significantly from values obtained from global literature surveys. Possible future improvements to the model structure were also identified, aimed at providing improved estimates of crop contamination levels for timescales in excess of those considered in this study. (U.K.)

  16. CeLAND: search for a 4th light neutrino state with a 3 PBq 144Ce-144Pr electron antineutrino generator in KamLAND

    Gando, A; Hayashida, S; Ikeda, H; Inoue, K; Ishidoshiro, K; Ishikawa, H; Koga, M; Matsuda, R; Matsuda, S; Mitsui, T; Motoki, D; Nakamura, K; Oki, Y; Otani, M; Shimizu, I; Shirai, J; Suekane, F; Suzuki, A; Takemoto, Y; Tamae, K; Ueshima, K; Watanabe, H; Xu, B D; Yamada, S; Yamauchi, Y; Yoshida, H; Cribier, M; Durero, M; Fischer, V; Gaffiot, J; Jonqueres, N; Kouchner, A; Lasserre, T; Leterme, D; Letourneau, A; Lhuillier, D; Mention, G; Rampal, G; Scola, L; Veyssiere, Ch; Vivier, M; Yala, P; Berger, B E; Kozlov, A; Banks, T; Dwyer, D; Fujikawa, B K; Han, K; Kolomensky, Yu G; Mei, Y; O'Donnell, T; Decowski, P; Markoff, D M; Yoshida, S; Kornoukhov, V N; Gelis, T V M; Tikhomirov, G V; Learned, J G; Maricic, J; Matsuno, S; Milincic, R; Karwowski, H J; Efremenko, Y; Detwiler, A; Enomoto, S

    2013-01-01

    The reactor neutrino and gallium anomalies can be tested with a 3-4 PBq (75-100 kCi scale) 144Ce-144Pr antineutrino beta-source deployed at the center or next to a large low-background liquid scintillator detector. The antineutrino generator will be produced by the Russian reprocessing plant PA Mayak as early as 2014, transported to Japan, and deployed in the Kamioka Liquid Scintillator Anti-Neutrino Detector (KamLAND) as early as 2015. KamLAND's 13 m diameter target volume provides a suitable environment to measure the energy and position dependence of the detected neutrino flux. A characteristic oscillation pattern would be visible for a baseline of about 10 m or less, providing a very clean signal of neutrino disappearance into a yet-unknown, sterile neutrino state. This will provide a comprehensive test of the electron dissaperance neutrino anomalies and could lead to the discovery of a 4th neutrino state for Delta_m^2 > 0.1 eV^2 and sin^2(2theta) > 0.05.

  17. A Brief Review of Past INL Work Assessing Radionuclide Content in TMI-2 Melted Fuel Debris: The Use of 144Ce as a Surrogate for Pu Accountancy

    D. L. Chichester; S. J. Thompson

    2013-09-01

    This report serves as a literature review of prior work performed at Idaho National Laboratory, and its predecessor organizations Idaho National Engineering Laboratory (INEL) and Idaho National Engineering and Environmental Laboratory (INEEL), studying radionuclide partitioning within the melted fuel debris of the reactor of the Three Mile Island 2 (TMI-2) nuclear power plant. The purpose of this review is to document prior published work that provides supporting evidence of the utility of using 144Ce as a surrogate for plutonium within melted fuel debris. When the TMI-2 accident occurred no quantitative nondestructive analysis (NDA) techniques existed that could assay plutonium in the unconventional wastes from the reactor. However, unpublished work performed at INL by D. W. Akers in the late 1980s through the 1990s demonstrated that passive gamma-ray spectrometry of 144Ce could potentially be used to develop a semi-quantitative correlation for estimating plutonium content in these materials. The fate and transport of radioisotopes in fuel from different regions of the core, including uranium, fission products, and actinides, appear to be well characterized based on the maximum temperature reached by fuel in different parts of the core and the melting point, boiling point, and volatility of those radioisotopes. Also, the chemical interactions between fuel, fuel cladding, control elements, and core structural components appears to have played a large role in determining when and how fuel relocation occurred in the core; perhaps the most important of these reaction appears to be related to the formation of mixed-material alloys, eutectics, in the fuel cladding. Because of its high melting point, low volatility, and similar chemical behavior to plutonium, the element cerium appears to have behaved similarly to plutonium during the evolution of the TMI-2 accident. Anecdotal evidence extrapolated from open-source literature strengthens this logical feasibility for

  18. The study of the effect of gamma radiation on the ionic and collodial solutions of 144Ce/III/ at trace concentration by the method of self-diffusion and centrifugation

    Gamma irradiation of a solution of trace concentration of 144Ce/III/ at pH 3.0 causes an increase in the self-diffusion coefficient of 144Ce/III/ and small decrease in its centrifugable fraction. The significant increase in the self-diffusion coefficient is observed after irradiation at pH 9.0 and 11.0 and on the centrifugation of these solutions an increased susceptibility of particles containing 144Ce/III/ to the coagulation accurs. The measurements were performed by a method of the open end capillary immersed into the excess of inactive solution and the self-diffusion coefficient calculated as described earlier. The solutions were irradiated either directly in the capillaries for the self-diffusion measurment fixed in the glass tubes or in borosilicate Sial glass sample tubes with subsequent pipetting into the capillaries. The dose rate of 60Co γ-radiation was about 0.4 Mrad. hour-1, the time of irradiation was 1.5 to 15 hours. The period between the end of the irradiation and the beginning of the self-diffusion measurement amounted to about 15 to 30 min. (F.G.)

  19. Radiochemical methods used by the IAEA's laboratories at Siebersdorf for the determination of 90Sr, 144Ce and Pu radionuclides in environmental samples collected for the International Chernobyl Project

    During the IAEA's International Chernobyl Project to assess the radiological consequences of the nuclear reactor accident, the Agency's Laboratories at Seibersdorf participated in the collection and analyses of environmental samples from the Soviet Union. Under Task 2 of this effort, the determination of the activity concentrations of 90Sr and the alpha-emitting Pu radionuclides was important for the corroboration of the official USSR environmental contamination maps. The present paper describes in detail the sampling methods and radiochemical procedures used for the 90Sr, 144Ce, 238Pu and 239,240Pu analyses in these samples with emphasis on the grass and soil treatments. (Author)

  20. Appendix to Health and Safety Laboratory environmental quarterly, March 1, 1976--June 1, 1976. [Tabulated data on content of lead in surface air and /sup 7/Be, /sup 95/Zr, /sup 137/Cs, /sup 144/Ce, and /sup 90/Sr in surface air, milk, drinking water, and foods sampled in USA

    Hardy, E.P. Jr.

    1976-07-01

    Tabulated data are presented on: the monthly deposition of /sup 89/Sr and /sup 90/Sr at some 100 world land sites; the content of lead and /sup 7/Be, /sup 95/Zr, /sup 137/Cs, and /sup 144/Ce in samples of surface air from various world sites; and the content of /sup 90/Sr in samples of milk, drinking water, and animal and human diets collected at various locations throughout the USA. (CH)

  1. Yield-Energy Dependence for 147Nd and 144Ce Under Strong Neutron Field

    QIAN; Jing; LIU; Ting-jin; SUN; Zheng-jun; SHU; Neng-chuan

    2012-01-01

    <正>The data of the fission product yield play an important role in the nuclear science technology and nuclear engineering because they are the key data in the calculation of the decay heat, shield design, nuclear verification, radiochemistry reprocessing and nuclear safety, etc. Especially, it is the essential data in fission power estimation for a fission device. It is well known that there exists a consecutive neutron spectrum with the energy from 1 keV to 15 MeV for a fission-fusion device. So in order to estimate the

  2. Oral Zn-DTPA therapy for reducing 141Ce retention in suckling rats

    In neonatal rats DTPA reduced the intestinal retention of cerium ingested as an additive in its chloride form to milk. It also reduced retention of absorbed cerium. A similar decrease of cerium retention in gut and whole body was obtained after simultaneous or 24 hours' delayed DTPA administration. (author)

  3. Quantitative analysis of fission products by γ spectrography

    The activity of the fission products present in treated solutions of irradiated fuels is given as a function of the time of cooling and of the irradiation time. The variation of the ratio (144Ce + 144Pr activity)/ 137Cs activity) as a function of these same parameters is also given. From these results a method is deduced giving the 'age' of the solution analyzed. By γ-scintillation spectrography it was possible to estimate the following elements individually: 141Ce, 144Ce + 144Pr, 103Ru, 106Ru + 106Rh, 137Cs, 95Zr + 95Nb. Yield curves are given for the case of a single emitter. Of the various existing methods, that of the least squares was used for the quantitative analysis of the afore-mentioned fission products. The accuracy attained varies from 3 to 10%. (author)

  4. Gazifikatsiya biomassy i ee perspektivy dlya proizvodstva elektricheskoi energii

    Vosecký, Martin; Skoblia, Sergej; Koutský, B.; Malecha, J.; Punčochář, Miroslav

    Minsk: BGTI, 2005, s. 72-78. ISBN 985-434-554-8. [Mezhudnarodnaya nauchno-tekhnichaskaya konferentsiya "Resursno- i enepgosberegayuschie tekhnologii i oborudovanie, ekologicheski bezopasnye tekhnologii". Minsk (BY), 16.11.2005-18.11.2005] R&D Projects: GA ČR(CZ) GA104/04/0829 Institutional research plan: CEZ:AV0Z40720504 Keywords : biomass * gasification * electricity production Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  5. Evolution of gamma artificial radioactivity in coastal sediments of the English Channel during the years 1976, 1977 and 1978

    During 1976-1977, a state of equilibrium was found to prevail for 106Ru and 144Ce, especially in the North-West Cotentin and the Norman-Breton gulf, where reconcentration of both radionuclides was observed with preferential enrichment of the latter over the former. Levels of 125Sb and 137Cs were found to be low but were difficult to interpret, because of the particular physico-chemical behavior of 125Sb and the long half-life of 137Cs. The results obtained for 103Ru, 141Ce, 95Zr may be explained entirely by the contribution of atmospheric fallout. 144Ce and 106Ru levels in the Norman-Breton gulf may be for the most part ascribed to La Hague disposals, radionuclide dispersal from the emissary being characterized by an eastward transfer of the soluble fraction and a westward transfer of the particulate fraction, with transit times which may last up to 2 years. The boundary between the areas submitted respectively to the twofold impact of fallout and industrial waste, and to fallout alone would appear to lie between the mouth of the Trieux river and Morlaix Bay. From a graphic representation of the relationship between radionuclides, empiric distribution laws for 106Ru and 137Cs were established from 144Ce level parameters characteristic of the areas considered (years 1976-1977)

  6. Behaviour of the radionuclides 125J, 85Sr, 134Cs and 144Ce in three typical sands of Northern Germany under conditions of water-unsaturated flow

    The investigations described in this study help to explain the migration of radionuclides, being in the seepage water, in the upper soil layers. We investigated the behaviour of the radionuclides of the elements J, Sr, Cs and Ce in three types of loose rocks taken from the C-horizon of characteristic soils existing in the surroundings of Gorleben (Lower Saxony). These loose rocks are medium- and fine-grained sands. In the laboratory we performed Batch and column experiments under the conditions of water-unsaturated flow. For these investigations we used an experimental rainwater, which we had prepared on the basis of the analytic mean values obtained for the rainwater of the Gorleben surroundings. (orig./RW)

  7. Assessment of selected fission products in the Savannah River Site environment

    Most of the radioactivity produced by the operation of a nuclear reactor results from the fission process, during which the nucleus of a fissionable atom (such as 235U) splits into two or more nuclei, which typically are radioactive. The Radionuclide Assessment Program (RAP) has reported on fission products cesium, strontium, iodine, and technetium. Many other radionuclides are produced by the fission process. Releases of several additional fission products that result in dose to the offsite population are discussed in this publication. They are 95Zr, 95Nb, 103Ru, 106Ru, 141Ce, and 144Ce. This document will discuss the production, release, migration, and dose to humans for each of these selected fission products

  8. Specific processes in solvent extractiotn of radionuclide complexes

    The doctoral thesis discusses the consequences of the radioactive beta transformation in systems liquid-liquid and liquid-ion exchanger, and the effect of the chemical composition of liquid-liquid systems on the distribution of radionuclide traces. A model is derived of radiolysis in two-phase liquid-liquid systems used in nuclear chemical technology. The obtained results are used to suggest the processing of radioactive wastes using the Purex process. For solvent extraction the following radionuclides were used: 59Fe, 95Zr-95Nb, 99Mo, sup(99m)Tc, 99Tc, 103Pd, 137Cs, 141Ce, 144Ce-144Pr, 234Th, and 233Pa. Extraction was carried out at laboratory temperature. 60Co was used as the radiation source. Mainly scintillation spectrometry equipment was used for radiometric analysis. (E.S.)

  9. High-temperature materials for MHD installations. Vysokotemperaturnye materialy dlya MGD-ustanovok

    Rekov, A.I.; Romanov, A.I. (eds.)

    1977-01-01

    The collection of articles was compiled on the basis of papers presented at the All-Union Conference on materials for MHD Installations in 1972. The collection also contains several articles which give results of studies made in 1973--1974. The articles are concerned with the development and investigation of high-temperature non-metallic materials (ceramic oxides, cermets, fire-resistant concrete, etc.) for various thermal units of a MHD installation (channel, combustion chamber, paragenerator, and others). Particular attention was given to the problem of electron and electric-insulation materials of the MHD-generator's channel. An examination is made of the physico-chemical aspects of producing materials and data are presented on studies of their composition and structure, and descriptions are given of the methods and research results from studies on thermo-mechanical strength, thermal and erosion resistance, electroconductivity, thermoemission, thermal conductivity, chemical resistance, and other properties of materials. The behavior of those materials was also tested in various MHD machines (U-02, U-25, and others). The collection is intended for specialists in the area of making and investigating materials for operating at high temperatures and in aggressive media.

  10. Isledovanie nanochastits, prednaznachenykh dlya adresnoy dostavki lekarstv metodami malouglovogo sinkhrotronogo isledovania i raseyaniya neutronov. Vnutrenaya struktura i funktsional'nost'

    Filippov, Sergey K.; Chytil, Petr; Konarev, P.; Papadakis, K. M.; Radulesku, A.; Pleštil, Josef; Štěpánek, Petr; Etrych, Tomáš; Ulbrich, Karel; Svergun, D.

    Gatchina : National Research Centre "Kurchatov Institute", Petersburg Nuclear Physics Institute B. P. Konstantinov, 2014. s. 72. [Meetings and Youth Conference on Neutron Scattering and Synchrotron Radiation in Condesed Matter (NSSR-CM-2014). 27.10.2014-31.10.2014, St. Petersburg] R&D Projects: GA ČR GAP108/12/0640 Institutional support: RVO:61389013 Keywords : nanoparticles * SAXS * SANS Subject RIV: CD - Macromolecular Chemistry

  11. Reconstruction of the composition of the Chernobyl radionuclide fallout and external radiation absorbed doses to the population in areas of Russia

    The results of reconstruction of the radionuclide composition of the Chernobyl fallout in the territories of Russia is presented. Reconstruction has been carried out by means of statistical analysis of the gamma spectrometry data on 2867 soil samples collected in the territories of Ukraine, Byelarus and Russia from 1986 to 1988. To verify the data, aggregated estimates of the fuel composition of the 4th block at the moment of the accident (available from the literature) have been used, as well as the estimates of activity released to the atmosphere. As a result, correlation and regression dependences have been obtained between the activities of the radionuclides most contributing to the dose (137Cs, 134Cs, 131I, 140Ba, 140La, 95Zr, 95Nb, 103Ru, 106Ru, 141Ce, 144Ce, 125Sb). Statistically significant regression relations between different pairs of radionuclides (including analysis of the 'noise' contribution to the data) depending on the distance between the point of sample collection and the power station are presented for the 'north-east track' - the northern part of the 30 km zone and southern part of the Gomel 'district (Byelarus) and the Briansk, Kaluga, Tula and Orel districts (Russia). A methodology is also described for reconstructing space-time characteristics of the contamination of the territories by major dose-forming radionuclides released from the Chernobyl NPP 4th unit. (Author)

  12. Radioactivity in surface air and precipitation in Japan after the Chernobyl accident

    Radioactive plumes from the Chernobyl reactor accident first passed over Japan on 3 May 1986. Measurements of 103Ru, 131I and 137Cs in rainfall and airborne dust collected at Chiba near Tokyo show that, in fact, at least two or more kinds of plume arrived during May. Their altitudes were calculated to be about 1500 m in early May and 6300 m in late May. Radionuclides detected in 33 precipitation samples collected by the network of radiation monitoring stations from 1 to 22 May were 7Be, 89Sr, 90Sr, 95Zr, 95Nb, 103Ru, 106Ru, sup(110m)Ag, 125Sb, sup(129m)Te, 131I, 132Te, 132I, 134Cs, 136Cs, 137Cs, 140Ba, 140La, 141Ce and 144Ce. The radiation was characterized by higher levels of the volatile nuclides, such as 103Ru, 132Te, 131I and 137Cs, than fallout levels in nuclear weapons testing, and by activity ratios of 0.48 and 14 for, respectively, 134Cs/137Cs and 89Sr/90Sr, as on 26 April. the fallout activity was higher in Northwestern Japan, the average depositions of 90Sr and 137Cs in Japan from 1 May (or 30 April) to 22 May being 1.4 Bq m-2 and 95 Bq m-2, inventories which are 14 and 550 times higher than the pre-Chernobyl values. (author)

  13. Biological effects of radiation: The induction of malignant transformation and programmed cell death

    In the Chernobyl explosions and fire, powderized nuclear fuel was released from the reactor core, causing an unexpected fallout. X-ray analysis and scanning electron microscopy showed that the isolated single particles were essentially pure uranium. These uranium aerosols contained all of the nonvolatile fission products, including the b-emitters, 95Zr, 103Ru, 106Ru, 141Ce, and 144Ce. The hot particles are extremely effective in inducing malignant transformation in mouse fibroblast cells in vitro. The major factor responsible for this effect is focus promotion caused by a wound-mediated permanent increase in cell proliferation (mitogenesis associated with mutagenesis). Transformed foci were analysed for the activation of c-abl, c-erb-A, c-erb-B, c-fms, c-fos, c-myb, c-myc, c-Ha-ras, c-Ki-ras, c-sis, and c-raf oncogenes at the transcriptional level. The pattern of oncogene activation was found to vary from focus to focus. Long interspersed repeated DNA (L1 or LINE makes up a class of mobile genetic elements which can amplify in the cell genome by retroposition. This element is spontaneously transcriptionally activated at a critical population density and later amplified in rat chloroleukaemia cells. UV light and ionizing radiation induce this activation prematurely, and the activation is followed by programmed cell death (apoptosis) in a sequence of events identical to that seen in LIRn activation occurring spontaneously

  14. Standard test method for gamma energy emission from fission products in uranium hexafluoride and uranyl nitrate solution

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 This test method covers the measurement of gamma energy emitted from fission products in uranium hexafluoride (UF6) and uranyl nitrate solution. It is intended to provide a method for demonstrating compliance with UF6 specifications C 787 and C 996 and uranyl nitrate specification C 788. 1.2 The lower limit of detection is 5000 MeV Bq/kg (MeV/kg per second) of uranium and is the square root of the sum of the squares of the individual reporting limits of the nuclides to be measured. The limit of detection was determined on a pure, aged natural uranium (ANU) solution. The value is dependent upon detector efficiency and background. 1.3 The nuclides to be measured are106Ru/ 106Rh, 103Ru,137Cs, 144Ce, 144Pr, 141Ce, 95Zr, 95Nb, and 125Sb. Other gamma energy-emitting fission nuclides present in the spectrum at detectable levels should be identified and quantified as required by the data quality objectives. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its us...

  15. Monte Carlo modeling of beta-radiometer device used to measure milk contaminated as a result of the Chernobyl accident

    This paper presents results of Monte Carlo modeling of the beta-radiometer device with Geiger-Mueller detector used in Belarus and Russia to measure the radioactive contamination of milk after the Chernobyl accident. This type of detector, which is not energy selective, measured the total beta-activity of the radionuclide mix. A mathematical model of the beta-radiometer device, namely DP-100, was developed, and the calibration factors for the different radionuclides that might contribute to the milk contamination were calculated. The estimated calibration factors for 131I, 137Cs, 134Cs, 90Sr, 144Ce, and 106Ru reasonably agree with calibration factors determined experimentally. The calculated calibration factors for 132Te, 132I, 133I, 136Cs, 89Sr, 103Ru, 140Ba, 140La, and 141Ce had not been previously determined experimentally. The obtained results allow to derive the activity of specific radionuclides, in particular 131I, from the results of the total beta-activity measurements in milk. Results of this study are important for the purposes of retrospective dosimetry that uses measurements of radioactivity in environmental samples performed with beta-radiometer devices.

  16. Problems in stabilizing the quality of brown coal fuel for powerful state regional electric power plants. Zadachi stabilizatsii kachestva burougol'nogo topliva dlya moshchykh GRES

    Varshavskiy, A.M.

    1984-01-01

    The change in the structure of the fuel balance of thermal electric power plants over the last decades is examined. The growing role of brown coals for coal dust combustion at the present time is shown. Data are cited which characterize the Kansko Achinskiy fuel and energy complex, the deposit of brown coal and the specifications on the quality of the coal. Characteristic to this are thick, complexly structured coal strata of high strength with substantial fluctuations in ash content, moisture level and heat creating capability. The powerful energy producing units of thermal electric power plants require a quite uniform fuel quality. The existing GOST 11717-78 insufficiently regulates the specifications for the quality of fuel for state regional electric power plants (GRES) which come from the different open pits of the Kansko Achinskiy basin. It is proposed that the coal be averaged and ground within the concentrating plant by means of cutting excavators and that corrections to the GOST be introduced.

  17. An investigation of the effectiveness of blending (averaging) brown coal for state regional electric power plants (GRES). Issledovaniye effektivnosti usredneniya burykh ugley dlya GRES

    Varshavskiy, A.M.

    1985-01-01

    The variability of the ash content of coal effects the specific expenditure of fuel by a state regional electric power plant for producing electric power. The studies were conducted at the Aleksandriyskiy thermal power plant (TeTs) number three and at the Zaporozhye, Yermakovskiy and Nazarovskiy state regional thermal power plants. It is established that a reduction in the mean square deviation of the hourly volumes of coal from 3 to 0.5 leads to a savings of 3.2 to 3.8 percent of coal and 2.4 to 2.9 percent brown coal. Regression equations are acquired. Correlation factors are calculated which do not exceed 0.7 percent of the reliable association between indicators.

  18. Radionuclide accumulation by aquatic biota exposed to contaminated water in artificial ecosystems before and after its passage through the ground

    This study was designed to investigate the comparative accumulation of radionuclides from contaminated water in artificial ecosystems before and after the water's passage through the ground. Fish, clams, algae, and an emergent vascular plant were experimentally exposed to mixtures of radionuclides in three aqueous streams. Two streams consisted of industrial water discharged directly into a leaching trench, and the same water after it had migrated through the ground for a distance of 260 meters. The third stream was river water, which served as a background or control. Biota exposed to river water in the control stream had very low concentrations of 60Co, less than 3 pCi per gram dry weight (pCi/g DW). Other radionuclides were essentially unmeasurable. Biota exposed to trench water accumulated very high relative concentrations of 60Co. Biota exposed to trench water also had measurable concentrations of 155Eu, 144Ce, 141Ce, 125Sb, 124Sb, 103Ru, 106Ru, 137Cs, 95Zr, 95Nb, 58Co, 54Mn, 59Fe, 65Zn, 90Sr, /sup 239,240/Pu, and 238Pu. Biota exposed to ground water had concentrations of 60Co that ranged between 50 and 1200 pCi/g DW. Fish flesh had the lowest concentration of 60Co and algae the highest. Strontium-90 was measured in the tissues of aquatic biota at concentrations ranging between 360 pCi/g DW in clam flesh to 3400 pCi/g DW in leaves and stems of Veronica. Leaves and fruits of tomato plants rooted in the ground water accumulated 90Sr at concentrations of 160 pCi in fruits and 4200 pCi in leaves. Data indicate that 60Co and 90Sr migrated through the ground along with ground-water flow and were available to all classes of aquatic biota and tomato plants rooted in the water via root uptake, sorption, and food chain transfers. 8 refs., 4 figs., 6 tabs

  19. Particle size distribution of radioactive aerosols after the Fukushima and the Chernobyl accidents

    Following the Fukushima accident, a series of aerosol samples were taken between 24th March and 13th April 2011 by cascade impactors in the Czech Republic to obtain the size distribution of 131I, 134Cs, 137Cs, and 7Be aerosols. All distributions could be considered monomodal. The arithmetic means of the activity median aerodynamic diameters (AMADs) for artificial radionuclides and for 7Be were 0.43 and 0.41 μm with GDSs 3.6 and 3.0, respectively. The time course of the AMADs of 134Cs, 137Cs and 7Be in the sampled period showed a slight decrease at a significance level of 0.05, whereas the AMAD pertaining to 131I increased at a significance level of 0.1. Results obtained after the Fukushima accident were compared with results obtained after the Chernobyl accident. The radionuclides released during the Chernobyl accident for which we determined the AMAD fell into two categories: refractory radionuclides (140Ba, 140La 141Ce, 144Ce, 95Zr and 95Nb) and volatile radionuclides (134Cs, 137Cs, 103Ru, 106Ru, 131I, and 132Te). The AMAD of the refractory radionuclides was approximately 3 times higher than the AMAD of the volatile radionuclides; nevertheless, the size distributions for volatile radionuclides having a mean AMAD value of 0.51 μm were very close to the distributions after the Fukushima accident. -- Highlights: • AMADs after the Fukushima and Chernobyl accidents in the Czech Rep. were determined. • The mean value of AMADs of the monitored nuclides from the NPP Fukushima was 0.43 μm. • Nuclides from the NPP Chernobyl fell into two categories – refractory and volatile. • The mean value of AMADs of volatile nuclides from the NPP Chernobyl was 0.51 μm. • AMADs of volatile nucl. from the NPP Chernobyl were 3× smaller than of the refractory radionuclides

  20. Environmental and health consequences in Japan due to the accident at Chernobyl nuclear reactor plant

    A comprehensive review was made on the results of national monitoring program for environmental radioactivity in Japan resulting from the accident at the Chernobyl nuclear power plant in USSR. Period of monitoring efforts covered by the present review is from 30th of April 1986 to 31st of May 1987. A radioactive cloud released from the Chernobyl nuclear reactor initially arrived in Japan on 30th of April 1986 as indicated by the elevated level of 131I, 137Cs and 134Cs activity in the total deposition on 30th of April and also by the increased 137Cs body burden noted on 1st of May. Almost all the radioactive nuclides detected in the European countries were also identified in Japan. For example, the observed nuclides were: 95Zr, 95Nb, 99mTc, 103Ru, 106Ru, 110mAg, 111Ag, 125Sb, 127Sb, 129mTe, 131I, 132Te, 132I, 133I, 134Cs, 136Cs, 137Cs, 140Ba, 140La, 141Ce and 144Ce. Among the above radionuclides, the country average concentration was determined for 131I, 137Cs and 134Cs in various environmental materials such as air, fresh water, soil, milk, leafy and root vegetables, cereals, marine products and other foodstuffs. In contrast to the sharp decline of 131I which was negligible after a few months, 137Cs showed a tendency to maintain its activity in foodstuffs at an appreciable level one year later. Collective effective dose equivalent and dose equivalent to thyroid in Japanese population due to 137Cs, 134Cs and 131I were estimated to be around 590 man Sv and 4760 man Sv, respectively. Corresponding values for the per caput dose equivalent are 5 μSv for whole body and 40 μSv for thyroid, respectively. (author)

  1. Pollution of atmospheric air with toxic and radioactive particulate matter investigated by means of nuclear techniques

    The application of spectrometric methods of nuclear techniques to the investigations of atmospheric air pollution by toxic and radioactive elements and results of these investigations conducted in the highly industrialized and urbanized regions of Poland have been presented. The method of precipitation of the samples, the measurements and analysis of radiation spectra of alpha and gamma radiation emitted by isotopes present in the samples have been described. The concentrations of toxic metal dust in the air have been evaluated by neutron activation and X-ray fluorescence analysis. Appropriate methods of measurement, calibration of instrument and the discussion of results have been presented. The work presents the results of investigations performed in Siersza within the years 1973-1974 and in Warsaw in the period of 1975-1977, which have permitted to estimate the mean monthly values of concentration in the atmospheric air of the following radioisotopes: 7Be, 54Mn, 95Zr, 103Ru, 106Ru, 125Sb, 131I, 137Cs, 140Ba, 141Ce, 144Ce, 226Ra, Th-nat, U-nat and the following stable elements: Sc, Cr, Fe, Co, Zn, As, Se, Sb, W, Pb. The analysis of changes in concentration of each particular artificial radioisotope in the air for the region of Poland in connection with Chinese nuclear explosions have been given. On the basis of the performed environmental investigations the method of analysis of relations between the concentrations of particular elements present in the dust has been discussed. The applications of this method have been presented. The hazard to the population and the environment caused by the radioactive and toxic dust present in the atmospheric air has been estimated. (author)

  2. Forage: A sensitive indicator for airborne radioactivity

    As a part of the radiological environmental monitoring program at the Joseph M. Parley Nuclear Plant to meet the requirements of NRC Regulations 10 CRF 50, Appendix I, routine sampling of forage was implemented. Indicator plots of forage (grass) were established at the plant site boundary in the two Meteorological sectors having the highest X/Q values for ground-level dispersion of airborne radioactivity. Likewise, a control plot was established in a sector having a significantly lower X/Q value at a distance of 18 miles. Procedures for maintenance of the grass plots, sampling of forage, and sample preparation for measurement of gamma radioactivity with a Ge (Li) detector were developed during the reported three year measurement period. Three atmospheric nuclear tests by the Peoples Republic of China in 1976 and 1977 has proven forage sampling to be convenient, sensitive, and in the judgement of the authors gives results which are superior to most other media sampled for airborne radioactivity. Typical measured levels of radioactivity from 150 to greater than 10,000 pCi/kg (dry weight) were obtained for the principal fission products in the Chinese bomb fallout, which included 95Zr-95Nb, 103Ru, 131I, 140Ba-140La, 141Ce, and 144Ce. On a unit weight basis the level of radioactivity measured was consistently higher for forage than for green leafy vegetables. This was attributed to the higher surface area for the forage. For comparison, plots of airborne concentrations for gross beta and particulate gamma emitters are shown during the time periods that include the Chinese nuclear tests. (author)

  3. On Jackson's theorem for the modulus of smoothness determined by a nonsymmetric generalised shift operator

    Potapov, Mikhail K.; Berisha, Faton M.

    2012-01-01

    In this paper a class of asymmetrical operators of generalised translation is introduced, for each of them generalised moduli of smoothness are introduced, and Jackson's and its converse theorems are proved for those moduli. ----- V eto\\v{i} rabote rassmatrivaetsya klass sesimmetrichnykh operatorov obobshchenogo sdviga, dlya kazhdogo iz nikh vvoditsya obobshchennye moduli gladkosti i dlya nikh dokazybaetsya teorma Dzheksona i teorema, obratnaya e\\v{i}.

  4. Revascularization of calvarial, mandibular, tibial, and iliac bone grafts in rats

    Pinholt, E M; Solheim, E; Talsnes, O;

    1994-01-01

    area of harvest of bone graft is important regarding early revascularization, but the results do not support the theory that different embryological mode of development is the cause since mandibula (high 141Ce index) and calvaria (low 141Ce index) are of membranous origin and iliac bone (high 141Ce...... index) and tibia (low 141Ce index) are of endochondral origin. The difference in revascularization between the different grafts may be explained by differences in quantity of cancellous bone since cancellous bone is revascularized faster than cortical bone....

  5. Radionuclides contamination of fungi after accident on the Chernobyl NPP

    Zarubina, Nataliia E.; Zarubin, Oleg L. [Institute for Nuclear Research of National Academy of Sciense, 03680, pr-t Nauki, 47, Kiev (Ukraine)

    2014-07-01

    Accumulation of radionuclides by the higher fungi (macromycetes) after the accident on the Chernobyl atomic power plant in 1986 has been studied. Researches were spent in territory of the Chernobyl alienation zone and the Kiev region. Our research has shown that macromycetes accumulate almost all types of radionuclides originating from the accident ({sup 131}I, {sup 140}Ba /{sup 140}La, {sup 103}Ru, {sup 106}Ru, {sup 141}Ce, {sup 144}Ce, {sup 95}Nb, {sup 95}Zr, {sup 137}Cs and {sup 134}Cs). They accumulate the long-living {sup 90}Sr in much smaller (to 3 - 4 orders) quantities than {sup 137}Cs. We have established existence of two stages in accumulation of {sup 137}Cs by higher fungi after the accident on the Chernobyl NPP: the first stage resides in the growth of the concentration, the second - in gradual decrease of levels of specific activity of this radionuclide. Despite reduction of {sup 137}Cs specific activity level, the content of this radionuclide at testing areas of the 5-km zone around the Chernobyl NPP reaches 1,100,000 Bq/kg of fresh weight in 2013. We investigated dynamics of accumulation of Cs-137 in higher fungi of different ecological groups. One of the major factors that influence levels of accumulation of {sup 137}Cs by fungi is their nutritional type (ecological group). Fungi that belong to ecological groups of saprotrophes and xylotrophes accumulate this radionuclide in much smaller quantities than symbio-trophic fungi. As a result of the conducted research it has been established that symbio-trophic fungi store more {sup 137}Cs than any other biological objects in forest ecosystems. Among the symbio-trophic fungi species, species showing the highest level of {sup 137}Cs contamination vary in different periods of time after the deposition. It is connected with variability of quantities of these radio nuclides accessible for absorption at the depth of localization of the main part of mycelium of each species in a soil profile. Soil contamination

  6. Radionuclides contamination of fungi after accident on the Chernobyl NPP

    Accumulation of radionuclides by the higher fungi (macromycetes) after the accident on the Chernobyl atomic power plant in 1986 has been studied. Researches were spent in territory of the Chernobyl alienation zone and the Kiev region. Our research has shown that macromycetes accumulate almost all types of radionuclides originating from the accident (131I, 140Ba /140La, 103Ru, 106Ru, 141Ce, 144Ce, 95Nb, 95Zr, 137Cs and 134Cs). They accumulate the long-living 90Sr in much smaller (to 3 - 4 orders) quantities than 137Cs. We have established existence of two stages in accumulation of 137Cs by higher fungi after the accident on the Chernobyl NPP: the first stage resides in the growth of the concentration, the second - in gradual decrease of levels of specific activity of this radionuclide. Despite reduction of 137Cs specific activity level, the content of this radionuclide at testing areas of the 5-km zone around the Chernobyl NPP reaches 1,100,000 Bq/kg of fresh weight in 2013. We investigated dynamics of accumulation of Cs-137 in higher fungi of different ecological groups. One of the major factors that influence levels of accumulation of 137Cs by fungi is their nutritional type (ecological group). Fungi that belong to ecological groups of saprotrophes and xylotrophes accumulate this radionuclide in much smaller quantities than symbio-trophic fungi. As a result of the conducted research it has been established that symbio-trophic fungi store more 137Cs than any other biological objects in forest ecosystems. Among the symbio-trophic fungi species, species showing the highest level of 137Cs contamination vary in different periods of time after the deposition. It is connected with variability of quantities of these radio nuclides accessible for absorption at the depth of localization of the main part of mycelium of each species in a soil profile. Soil contamination by 137Cs is one of the principal abiotic influences on the accumulation of this radionuclide by fungi

  7. [Comparative analysis of the radionuclide composition in fallout after the Chernobyl and the Fukushima accidents].

    Kotenko, K V; Shinkarev, S M; Abramov, Iu V; Granovskaia, E O; Iatsenko, V N; Gavrilin, Iu I; Margulis, U Ia; Garetskaia, O S; Imanaka, T; Khoshi, M

    2012-01-01

    The nuclear accident occurred at Fukushima Dai-ichi Nuclear Power Plant (NPP) (March 11, 2011) similarly to the accident at the Chernobyl NPP (April 26, 1986) is related to the level 7 of the INES. It is of interest to make an analysis of the radionuclide composition of the fallout following the both accidents. The results of the spectrometric measurements were used in that comparative analysis. Two areas following the Chernobyl accident were considered: (1) the near zone of the fallout - the Belarusian part of the central spot extended up to 60 km around the Chernobyl NPS and (2) the far zone of the fallout--the "Gomel-Mogilev" spot centered 200 km to the north-northeast of the damaged reactor. In the case of Fukushima accident the near zone up to about 60 km considered. The comparative analysis has been done with respect to refractory radionuclides (95Zr, 95Nb, 141Ce, 144Ce), as well as to the intermediate and volatile radionuclides 103Ru, 106Ru, 131I, 134Cs, 137Cs, 140La, 140Ba and the results of such a comparison have been discussed. With respect to exposure to the public the most important radionuclides are 131I and 137Cs. For the both accidents the ratios of 131I/137Cs in the considered soil samples are in the similar ranges: (3-50) for the Chernobyl samples and (5-70) for the Fukushima samples. Similarly to the Chernobyl accident a clear tendency that the ratio of 131I/137Cs in the fallout decreases with the increase of the ground deposition density of 137Cs within the trace related to a radioactive cloud has been identified for the Fukushima accident. It looks like this is a universal tendency for the ratio of 131I/137Cs versus the 137Cs ground deposition density in the fallout along the trace of a radioactive cloud as a result of a heavy accident at the NPP with radionuclides releases into the environment. This tendency is important for an objective reconstruction of 131I fallout based on the results of 137Cs measurements of soil samples carried out at

  8. The results of using space photographic information to study the geological structure of the Pechora coal basin. Rezultaty primeneniya kosmicheskoy foroinformatsii dlya izucheniya geologicheskogo stroyeniya Pechorskogo ugol'nogo basseyna

    Zhuravlev, A.V.

    1983-01-01

    The possibilities of space structural analysis as applied to the Pechora basin are examined. A number of first order structures are identified directly on the space photographs (the Korotaikhinsk depression, the Chernysheva uplift and the Paykhoyskiy anticlinorium and so on). Ring shaped morphostructures are confined to the uplifts of the basement rock and the cap, to periclinal parts of the depressions and the points of crossing and confluence of linear positive structures. The results are cited of a comparison of the rose diagrams of the lineaments and the fracture faults in the basin as a whole and in its individual structures. Charts of the density of the nodes of intersection, the thickness and density of the lineaments and the tectonic field intensity are built for the northern part of the Chernyshev chain and the Losyu Rogovskiy depression, based on an analysis of which the zones of high concentration of lineaments are identified. A conclusion is drawn about their affinity to positive structures of different regions.

  9. Influence of variations in dose and dose rates on biological effects of inhaled beta-emitting radionuclides

    The biological effects of inhaled β-emitting radionuclides, 90Y, 91Y, 144Ce and 90Sr, are being investigated in beagle dogs that received single acute exposures at 12 to 14 months of age. The aerosols studied have included 91YC13,144CeC13, 90SrC12, and 90Y, 91Y, 144Ce or 90Sr in aluminosilicate particles. Thus, 91YCl3, 144CeCl3 and the aluminosilicate containing radionuclide particles all resulted in significant exposures to lung; 91YC13, 144CeC13 an 90SrC12 resulted in significant exposures to bone; 91YC13 and 144 CeC13 resulted in significant exposures to liver. The higher initial doserate exposures have been more effective than low dose-rate exposures on a per-rad basis in producing early effects. To date (144CeO2, it was observed that, on a μCi initial lung burden per kilogram body weight basis, mice did not develop pulmonary tumours whereas beagle dogs did. To fid out the reason for this observation mice have been repeatedly exposed by inhalation to 144CeO2 to maintain lung burdens of 144Ce that resulted in radiation dose rates similar to that observed in beagle dogs. Several of the repeatedly exposed mice developed malignant pulmonary tumours. Thus, with similar dose rates and cumulative doses to the lung, mice and dogs responded in a similar manner to chronic β radiation

  10. Nasal carcinomas in beagle dogs after inhalatioon of relatively soluble forms of beta-emitting radionuclides

    Beagle dogs were exposed by inhalation to relatively soluble forms of three beta-emitting radionuclides and are being held for life span observation to evaluate hazards associated with nuclear power production. Dogs were exposed to graded activity levels of 91YCl3, 144CeCl3 or 90SrCl2. With 91YCl3 and 144CeCl3, significant radiation dose was delivered to liver, respiratory tract, and skeleton. With 90SrCl2, the dose was essentially to skeleton. Nasal cavity squamous cell carcinomas have been the most frequent neoplasms in the 91Y and one of the most frequent in the 144Ce study while relatively few have been seen after 90Sr exposure. Also one nasal cavity hemangiosarcoma was seen in the 144Ce study. The 90Sr-exposed dogs have survived longer after exposure and have higher skeletal radiation doses than do the dogs exposed to 91Y or 144Ce. The greater incidence of nasal carcinomas can be explained by the finding of high concentrations of the lanthanides, 91Y and 144Ce, associated with the nasal turbinate epithelium

  11. Il personaggio scontornato in Škola dlja Durakov. Dal romanzo di Saša Sokolov agli adattamenti teatrali

    Irina Marchesini

    2012-01-01

    Sokolov’s Shkola dlya Durakov (A School for Fools, 1976) is an extremely complex novel, which “depicts [the] world”, as D. Barton Johnson (1986:640)[1] poignantly observes, “through the eyes, and pure, if eccentric, language, of a schizophrenic youth”. How is it possible to translate such linguistic features and the effects they create into another medium? This question lies at the core of my proposal, which aims to approach the problem of intermedial transla...

  12. On a connection between a generalised modulus of smoothness of order~$r$ and the best approximation by algebraic polynomials

    Potapov, Mikhail K.; Berisha, Faton M.

    2012-01-01

    In this paper an asymmetrical operator of generalised translation is introduced, the generalised modulus of smoothness is defined by its means and the direct and inverse theorems in approximation theory are proved for that modulus. ----- V danno\\v{i} rabote vvoditsya nesimmetrichny\\v{i} operator obobshchennogo sdviga, s ego pomoshchyu opredelyaetsya obobshchenny\\v{i} modul' gladkosti i dlya nego dokazyvaetsya pryamaya i obratnaya teoremy teorii priblizheni\\v{i}.

  13. Validity of chalk and bentonite application in soil and water on reducing the absorption of ratio-strontium and radio-cerium by crop

    Effects of the chalk and bentonite application in soil and surface water respectively on reducing the absorption of 89Sr and 141Ce by crop (especially in the edible part of crop) were studied by using isotope tracer techniques. The results showed that the specific activity of 89Sr in the ryegrass and Chinese cabbage could be decreased significantly by chalk application in the soil. The reduced ratio of 89Sr absorption of Chinese cabbage and ryegrass reached 77.7% and 35.2% respectively with the chalk application of 20 g/kg soil. The specific activity of 89Sr in ryegrass and Chinese cabbage followed obvious negative linear correlation with the quantity of application chalk in the soil. The specific activity of 141Ce in surface water, chaff and brown rice decreased by application bentonite in the surface water, which led to the lower accumulation of 141Ce in paddy. However, the absorption and accumulation of 141Ce in root and straw could not be changed. The specific activity of 141Ce in soil followed a negative exponential relation with depth of soil profile

  14. Genetic effects induced by radionuclides in the populations of the chlorella and antimutagenic influence of the vitamins C and B12

    Genetic influence of 90Sr, 137Cs and 144Ce on the chlorella populations has been studied, as well as antimutagenic effect of C and B12 vitamins on the influenced by 90Sr and 144Ce chlorella populations. The radionuclides 90Sr, 137Cs and 144Ce have been determined to increase the number of lethal and mutant cells in the chlorella populations. It has been shown that according to the influence of the number of lethally injured cells the radionuclides under study (within the concentration range 3.7X104 - 3.7X106 Bk/l) may be presented by the sequence 144Ce>137Cs≥90Sr, while according to the influence of the number of mutant cells - by the reverse sequence 90Sr>137Cs≥144Ce. Such different effect of the radionuclides on the chlorella populations may, possibly, be explained by different physical-chemical state of these radionuclides in water medium, their different uptake mechanism in plant cells, and different localization in them. A conclusion is drawn that C and B12 vitamins reduce radiosensitivity of water organisms, especially their lethality. B12 vitamin is stornger a mutagen than vitamin C

  15. Elimination of cerium-144 - physical and biological characteristics

    The decontamination efficiency of the preparation pentacyn (CaNa3-DTPA) with regard to radiocerium was evaluated. Investigated were not only physical parameters (radionuclide kinetics, absorbed doses decrease), but also morphological and biochemical indexes. Four groups of male Wistar rats were treated accordingly with 144Ce; 144Ce + pentacyn; external irrradiation + 144Ce; external irradiation + 144Ce + pentacyn. External gamma irradiation was performed with a dose of 260 cGy, 144Ce (1480 kBq/animal) was introduced intratarcheally 1 h after external irradiation. Pentacyn was administred according to the following scheme, ensuring maximal efficiency and minimal toxicity: intratracheally administration 30 min after radionuclide intake by 0.2 ml and subsequent intraperitoneally applications on days 1, 3, 5, 7, 10 and 17 by 0.5 ml. Determined were the following parameters characterizing the development of fibrous process: the quantity of oxyproline in collagen, the quantity of hexosamine in lung tissues, the changes in dry mass and heart camera index. It was concluded that biological criteria are important component of the decontamination efficiency evaluation

  16. Physiological and genetic effects induced in the chlorella culture by radionuclides

    Radionulcides 90Sr. 137Cs and 144Ce suppress chlorella populations in 37-10-6-37X10-4 Bk/e copcentration range; they increase the amount of lethally damaged and mutant cells at that. Investigated radionuclides can be presented in the form of 144Ce > 137Cs > 90Sr series with respect to their effect on the intensity of chlorella population photosynthesis and amount of lethally damaged cells. as well as accumulation levels, and in the form of 90Sr 137Ce > 144Ce series with negative sequence with respect to the effect on cell density, especially on the amount of mutant cells. The inverse relationship betWeen the change of photosynthesis intensity and the amount of lethally damaged cells, as well as betWeen the change of cell density and the maount of mutant cells was observed during radionuclide effect on chlorella populations

  17. Combinative effect of medium physical and chemical factors on the penetration and localization of some radionuclides in water plant cells

    As a result of the experiments, carried out with the charophytes algae Nitellopsis obtusa, gathered from lake Drukshyaj (the North-East part of the Lithuanian SSR) in 1985, it has been determined that the 90Sr, 144Ce and 137Cs radionuclides accumulation by water plant cell constituents (wall, protoplasm, vacuole) is substantially influenced by the water temperature, the chemical substances, which change the water structure, as well as the combinative effect of these factors. An identical character of the changes of the accumulation factors of 90Sr and 137Cs, which are found in the water solutions in an ionic form, and slightly different character in the case of 144Ce, which exists by 85% in the form of colloid particles, have been noted. In the case of 144Ce the influence of the physical as well as chamical factors on the cell walls is felt stronger than on the inner cell membranes

  18. Assessment of a cerium---praseodymium-144 inhalation case

    A case involving an acute exposure to a 144Ce-144Pr contaminated atmosphere is presented with a discussion of the treatment and evaluation of data collected out to 800 days post intake. Treatment included irrigation of the upper nasal passages with normal saline, nebulization with normal saline mist and DTPA therapy. Assessment of the deposition and the resulting dose commitment was based on in vivo measurements and excretion data. The initial pulmonary burden, which cleared with three distinct half times, was estimated at 2.1 μCi of 144Ce

  19. Assessment of a cerium-praseodymium-144 inhalation case

    A case involving an acute exposure to a 144Ce-144Pr-contaminated atmosphere is presented with a discussion of the treatment and evaluation of data collected up to 800 days post-intake. Treatment included irrigation of the upper nasal passages with normal saline, nebulization with normal saline mist, and intravenous DTPA therapy. Assessment of the deposition and the resulting dose commitment was based on in vivo measurements and excretion data. The initial pulmonary burden, which cleared with three distinct half-times, was estimated at 2.1 μCi of 144Ce. (author)

  20. Separation of radioactive substances by anodic electrolysis

    In experiments on the electrodeposition of radioisotopes on a platinum anode it was observed that the isotopes could be classified into: (1) those whose cations are deposited as oxides; and (2) those whose cations are only adsorbed on the anode. Under given conditions this difference can be used to separate ions of the two groups. In the present paper, experimental details are given of the separation of 144Ce from 140La. The separation of 144Ce from uranium fission products in the presence of uranyl ion is also discussed. (U.K.)

  1. Toxicity studies of inhaled beta-emitting radionuclides: status report

    The influence of total dose and dose rate on the effects of inhaled beta-emitting radionuclides is being studied in laboratory animals. The radionuclides are inhaled either in a relatively soluble form (90SrCl2, 144CeCl3, 91YCl3 or 137CsCl) or in a relatively insoluble form in fused aluminosilicate particles. The organs affected depend on the solubility and chemical characteristics of the radio isotopes. Studies with young adult dogs are complemented with comparable studies in other species (mice, rats and Syrian hamsters), with animals of different ages and with animals repeatedly exposed to 144Ce

  2. Toxicity studies of inhaled beta-emitting radionuclides - status report

    The influence of total dose and dose rate pattern on the effects of inhaled β-emitting radionuclides is being studied in laboratory animals. The inhaled radionuclides were either in a relatively soluble form (90SrCl2, 144CeCl3, 91YCl3, or 137CsCl), or in a relatively insoluble form in fused aluminosilicate particles. The organs affected depend on the solubility and chemical characteristics of the radionuclides. Studies with young adult dogs are complemented by comparable studies in other species (mice, rats, and Syrian hamsters), with animals of different ages and animals repeatedly exposed to 144Ce. 12 references, 2 figures, 2 tables

  3. The relationship between revascularisation and osteogenesis in fresh or demineralised bone grafts

    Solheim, E; Pinholt, E M; Talsnes, O;

    2001-01-01

    Bone formation generally depends on adequate blood flow. Failure of bone grafts has been attributed to delayed revascularisation of the graft. We compared the relationship between revascularisation and osteogenesis, evaluated as entrapment of (141)Ce-labelled microspheres and uptake of (85)Sr, re...

  4. Revascularisation of fresh compared with demineralised bone grafts in rats

    Solheim, E; Pinholt, E M; Talsnes, O;

    2001-01-01

    Revascularisation of bone grafts is influenced by both the anatomical origin and the pre-implantation processing of the graft. We investigated the revascularisation by entrapment of 141Ce (cerium)-labelled microspheres in large, fresh and demineralised syngeneic grafts of predominantly cancellous...

  5. Separation of cerium from high level waste solution of Purex origin

    A simple solvent extraction procedure for the separation of 144Ce from Purex high level waste (HLW) is described. 2-ethylhexyl 2-ethylhexyl phosphonic acid (KSM-17) has been used as extractant. About 10 mCi of cerium was separated from HLW using this technique. This method is amenable for automation and scale up. (author)

  6. Comparison of the effects of inhaled alpha- and beta-emitting radionuclides on pulmonary function in the dog

    Alterations of pulmonary function in representative groups of dogs developing nonneoplastic lung disease, after single inhalation exposures to cerium-144 or plutonium-238 in relatively insoluble particulate forms, were compared. The inhaled particles had similar aerodynamic diameters and effective half-lives of retention in the lung. The mean initial lung burdens of the 144Ce- and 238Pu-exposed groups were 51 and 0.65 μCi/kg of body weight, respectively. Because of the respective ranges of the beta emissions from 144Ce and the alpha emissions from 238Pu, the lungs of the 144Ce-exposed dogs were relatively uniformly irradiated, whereas only approximately 6% of the lung tissue of rates to the 238Pu-exposed dogs was irradiated. The calculated average dose rates to the irradiated tissue were similar for both radionuclides. Pulmonary function was measured serially without sedation. Both groups developed progressive, restrictive lung disease, which ended in death from pulmonary failure. Dogs that inhaled 144Ce had an early reduction of CO diffusing capacity followed by a progressive mechanical and gas-exchange impairment similar to that reported for dogs and men exposed to external irradiation. Dogs that inhaled 238Pu had increased respiratory frequencies which often persisted for months before mechanical and gas-exchange abnormalities became evident

  7. Radiation-induced liver lesions in beagle dogs

    The risk for liver disease from internally deposited beta-emitting radionuclides is unknown because there are no human populations exposed to hepatotropic beta-emitting radionuclides available for study. In this report, we discuss the hepatic lesion in dogs exposed to a beta-emitting radionuclide, 144CeCl3, and held for their life spans

  8. Effect of tropicamide on ocular blood flow in the rabbit

    Intracardiac injection of 15 microspheres labeled with 85Sr (strontium) and 141Ce (cerium) were used to determine ocular blood flow in seven rabbits before and 25 min after bilateral application of tropicamide to the cornea. By using two different isotopes distinguishable under gammaspectrometry, each animal served as its own control. After administration of two drops of 1% tropicamide, no significant difference in blood flow between treated and untreated eyes was observed

  9. Decontamination of a radioactive process waste water by adsorbing colloid flotation

    As a part of a research programme on the treatment of a radioactive process waste water by foam separation techniques, adsorbing colloid flotation was tested to remove 144Ce, 60Co, 65Zn and 89Sr from the waste water. Potassium oleate was used as the collector, and Fe(III) hydroxide, Al(III) hydroxide or Co(II) hydroxide as the coprecipitant. Under the optimal conditions; removals exceeding 99% could be achieved for 65Zn with any of the tested coprecipitants, for 144Ce with Fe(III) and Co(II) hydroxides and for 60Co with only Co(II) hydroxide. For 89Sr removals > 90% could be achieved with only Fe(III) hydroxide. The adsorbing colloid flotation process was compared with both chemical precipitation and ion exchange, and advantages of adsorbing colloid flotation were enumerated. (author)

  10. Decontamination of radioactive process waste water by adsorbing colloid flotation

    Adsorbing colloid flotation was tested to remove 144Ce, 60Co, 65Zn, and 89Sr from radioactive process waste water. Potassium oleate was used as the collector, and Fe(III) hydroxide, Al(III) hydroxide or Co(II) hydroxide as the coprecipitant. Under optimal conditions, removals exceeding 99% could be achieved for 65Zn with any of the tested coprecipitants, for 144Ce with Fe(III) and Co(II) hydroxides and for 60Co with only Co(II) hydroxide. For 89Sr removals of 90% could be achieved only with Fe(III) hydroxide. The adsorbing colloid flotation process was compared with both chemical precipitation and ion exchange. Advantages of adsorbing colloid flotation are discussed. (author)

  11. Separation of plutonium from uranium and fission products in the zirconium pyrophospate column

    Distribution coefficients were of the following ions were determined in the system zirconium pyrophosphate - aqueous solution HNO3 : Pu3+, Pu4+, PuO22+, UO22+, 234Th2+, 95Zr, 95Nb, 106Ru, 144Ce3+, 90Sr2+, 137Cs+, 59Fe3+ and 59Fe2+. According to the distribution coefficients it can be concluded that the separation of some cations is possible. This was proved by using separation columns. The following successful separations were completed: 90Sr2+ from 90I3+, 90Sr2+ from 90I3+ and 1'37Cs+, UO2+ from 234Th4+, Pu4+ from UO22+, 95Zr, 95Nb, 106Ru, 144Ce3+, 90Sr2+, 137Cs+. Decontamination factors of plutonium from the mentioned cations were determined. It was found that the sorption of Cs+ and Sr2+ is based on ion exchange

  12. Accumulation and excretion of radionuclides by alga Chara tomentosa

    It has been found in the course of the study of accumulation and excretion of radionuclides by alga chara tomentosa that 55Fe, 60Co, 91Y are accumulated by living and dead components of alga chara tomentosa to a far greater extent and are stronger retained than 90Sr, 137Cs, 144Ce. The main part of the absorbed quantities of all investigated nuclides (80-92%) is fixed on the surface of the plant in the ''cortex'' layer

  13. Radio-isotope converter

    Due to the surface power density required for thermoelectric and thermionic converters, available radioactive sources are surveyed and listed. Curves of specific minimum diameter versus thermal flux density are given. 210Po and 242Cm appear to be suitable for direct thermionic when alpha emitters such as 238Pu and 244Cm are still suitable for thermoelectric conversion. This mode will also work with beta emitters 170Tm, 90Sr, 144Ce and 137Cs. Some thermoelectric radioisotope heated converters are suggested. (authors)

  14. Electrochemical investigation of rare earth amalgams

    Using the method of filtration of heterogeneous samarium amalgams, containing radioactive isotopes sup(144)Ce and sup(152)Eu, it has been shown that cerium is inserted into the solid phase of samarium amalgam, whereas europium does not cocrystallize with samarium. The solubility of praseodymium, neodymium, and gadolinium in mercury has been determined on the basis of the curves current VS time of decomposition of heterogeneous amalgams of these metals

  15. High voltage deposition of daughter 144Pr on platinum electrode from chlorbenzene solution of cerium 8-hydroxyquinolinate

    The deposition of 144Pr, carrier-free, on platinum electrode, formed by beta-decay of 144Ce which was in the form of cerium tetrakis (8-hydroxyquinolinate) chelate in chlorobenzene, was studied in dependence on time and intensity of the electric field. The amount of 144Pr deposited on the cathode after 20 min at the intensity of electric field 8 kV cm-1 was 14% of its total equilibrium amount in the solution. The proportion of 144Pr formed in the solution as ions was found by extrapolating the experimental relationships to be 23%. This value was similar to that of the break-up of molecular forms under the formation of simple 144Pr ions expected on the basis of the decay scheme of 144Ce and the mechanism of the energy transfer inside the atoms and molecular systems. On the basis of the mobility of cations found (9.6x10-5 cm2kV-1s-1) it was assumed that deposited ions were probably monotypes. The amount of 144Pr deposited on the anode was about 1% and that of 144Ce on both the cathode and the anode (caused by adsorption) was 0.5 to 1%. (author)

  16. Comparison of the effects of inhaled alpha- and beta-emitting radionuclides on pulmonary function of the dog

    Pulmonary function changes of representative dogs after inhalation of a relatively insoluble form of 144Ce in fused aluminosilicate particles and 238PuO2 were compared. Both radionuclide forms had approximately the same effective half-life, but the 238PuO2 irradiated 11 percent of the lung while the 144Ce irradiated 100 percent. Both groups developed restrictive lung disease progressing to pulmonary failure but the sequence of functional changes differed. The first change in dogs that inhaled 144Ce was a reduced CO diffusing capacity followed later by changes in breathing pattern, lung compliance and alveolar-capillary O2 exchange. The first change in dogs that inhaled 238PuO2 was an increase in respiratory frequency which persisted for several months before nearly simultaneous changes in diffusing capacity, compliance and gas mixing. An impairment in alveolar-capillary O2 exchange occurred later in dogs that inhaled 238PuO2. Functional alterations of both groups in pulmonary failure were similar. The differences in the pattern of functional changes were thought to be related to differences in dose pattern, but the exact relationships are unknown

  17. Pulmonary carcinogenesis and chronic beta irradiation of lung

    Light water nuclear power reactor fuel cycles at various stages contain substantial quantities of β-emitting radionuclides. Thus, in the event of an accident, there is potential for inhalation exposure of man to various types and forms of β-emitting radionuclides. In order to study the biological effects of such potential exposures, a series of life span studies have been initiated in which beagle dogs have been exposed to inhalation to achieve graded lung burdens of a relatively insoluble fused clay form of β-emitting radionuclides. The specific radionuclides, 90Y, 91Y, 144Ce, or 90Sr, were selected on the basis of physical half-life to produce a variety of radiation-dose patterns to the lung. Early effects have been the development of radiation pneumonitis and progressive pulmonary fibrosis. In general, dogs which receive high- and rapidly-declining dose-rate exposure from 90Y or 91Y die earlier and at lower cumulative doses than dogs exposed to 144Ce or 90Sr. By contrast, the incidence of later-occurring malignant lung tumors and the degree of inflammatory response is greater in dogs which received protracted low dose-rate exposure associated with 144Ce and 90Sr. Of particular note is the nature of the lung tumors thus far observed

  18. Study of the radfioisotopic composition of rain in 2.05 1986 in Bucharest-Magurele area

    The paper presents the activities of radionuclides in the rain that fell in Bucharest-Magurele area on May 2nd, 1986. The artificial radionuclides measured were: Sr-89, Sr-90, Ru-103, Ru-106, Sb-125, I-131, (I+Te)-132, Cs-134, Cs-137, (Ba+La)-140, Ce-141, Ce-144, originating in the nuclear accident at Chernobyl. The activities of I-131 and Cs-137 were 28700 Bq/m2 and 3610 Bq/m2 respectively. (authors)

  19. Measurement of leaching from simulated nuclear-waste glass using radiotracers

    The use of radiotracer spiking as a method of measuring the leaching from simulated nuclear-waste glass is shown to give results comparable with other analytical detection methods. The leaching behavior of 85Sr, 106Ru, 133Ba, 137Cs, 141Ce, 152Eu, and other isotopes is measured for several defense waste glasses. These tests show that radiotracer spiking is a sensitive, multielement technique that can provide leaching data, for actual waste elements, that are difficult to obtain by other methods. Additionally, a detailed procedure is described that allows spiked glass to be prepared with a suitable distribution of radionuclides

  20. Nuclear Decay Data for the International Reactor Dosimetry Library for Fission and Fusion (IRDFF): Updated Evaluations of the Half-Lives and Gamma Ray Intensities

    Chechev, Valery P.; Kuzmenko, Nikolay K.

    2016-02-01

    Updated evaluations of the half-lives and prominent gamma ray intensities have been presented for 20 radionuclides - dosimetry reaction residuals. The new values of these decay characteristics recommended for the IRDFF library were obtained using the approaches and methodology adopted by the working group of the Decay Data Evaluation Project (DDEP) cooperation. The experimental data published up to 2014 were taken into account in updated evaluations. The list of radionuclides includes 3H, 18F, 22Na, 24Na, 46Sc, 51Cr, 54Mn, 59Fe, 57Co, 60Co, 57Ni, 64Cu, 88Y, 132Te, 131I, 140Ba, 140La, 141Ce, 182Ta, 198Au.

  1. Deposition and retention of radioactive aerosols on desert vegetation

    Deposition velocities and retention times were obtained for submicron aerosols of 134Cs and 141Ce on a shrub species (Artemisia tridentata) and a grass (Elymus elimoides) in a natural desert environment. Submicron aerosols of these two nuclides were artificially generated and released over a sagebrush community in southeast Idaho during each of three seasons: spring, summer and winter, to determine the effects of weathering and plant development on aerosol deposition and retention. Information on friction velocities, roughness lengths, and particle size was also obtained

  2. Reconstruction of dose on the basis of forest litter activity measurements (case studies)

    In a large scale investigation of Polish forest litter contamination performed in recent years we observed the variety of Chernobyl fallout in Poland. Besides large differences in the radiocaesium contamination levels, we found a non-uniform isotopic composition of the fallout; in the north-eastern part of the country we found enhanced (relative to caesium) amounts of non-volatile radioisotopes. We were still able to detect 144Ce, 154Eu and 155Eu as well as plutonium isotopes of Chernobyl origin. 7 refs

  3. Radionuclide volatilization during plasmachemical reprocessing of radioactive wastes

    Volatilization of 137Cs, 60Co, 90Sr, 144Ce and α-active radionuclides under high temperature utilization of solid and liquid low- and intermediate level radioactive wastes is studied. Low temperature plasma of arc plasmatroned was used as a heat carrier in the laboratory conditions and on experimental installation with shaft furnace and direct flow plasma-chemical reactor. The lowest radionuclides lost (1-2%) was observed from the shaft furnace due to the presence of radionuclides sorbiting layer of wastes

  4. The dispersion of pollutants in the Romanian rivers Olt, Somes and Danube

    The paper describes the results obtained in three tracer experiments carried out into the Romanian rivers Olt and Somes as well as into the Romanian part of the Danube by using the radioactive tracer 82Br. The possibility of a radioactive discharge to occur from the Cernavoda Nuclear Power Plant bring to focus also knowing of the distribution of fission products between water and solid suspended material. Consequently there were also studied and presented the distribution coefficients of the radionuclides 131I, 99Mo, 144Ce, 137Cs, and 95Zr for clay, loess and the particular alluvium collected from the Danube bed. (author)

  5. Influence of complex formation on extraction of some fission products by sorption on inorganic sorbents

    Sorption of fission products of radionuclides 137Cs, 89,90Sr, 90,91Y, 86Rb, 133Ba, 95Zr+95Nb, 95Nb, 103,106Ru, 141,144Ce, 115mCd, 113Sn, 125Sb by hydroxides Fe(III), Mn(IV) on the background of 1 mol/l of NaNO3 at the pretense of ions SO42-, C2O42- at a wide ph range (1+14) is studied in present work. Optimal conditions of extraction of each radionuclide by sorption on inorganic sorbents are defined.

  6. Life-span health effects of relatively soluble forms of internally deposited beta-emitting radionuclides

    As part of a large research effort to study the lifetime health risks of inhaled radionuclides, Beagle dogs inhaled 90SrCl2 or 144CeCl3 or were injected intravenously with 137CsCl. Because these three compounds were soluble in body fluids, the resulting widely differing patterns of radionuclide distribution and dose reflected tissue affinities of the elements involved. Long-term health effects, predominantly cancers, were seen in the organs receiving the highest doses. Investigations are continuing on the extent to which other less irradiated organs may have also been affected

  7. Appendix to Health and Safety Laboratory environmental quarterly report. [Fallout radionuclides deposited and in surface air at various world sites; /sup 137/Cs and /sup 90/Sr in milk and drinking water in New York City; and stable Pb in surface air

    Hardy, E.P. Jr.

    1977-07-01

    Tabulated data are presented on the deposition of fallout /sup 89/Sr and /sup 90/Sr at various world land sites through 1976; the ..gamma.. spectra and content of /sup 7/Be, /sup 95/Zr, /sup 137/Cs, /sup 144/Ce, /sup 90/Sr, /sup 210/Pb, /sup 238/Pu, /sup 239/Pu, and stable Pb in samples of surface air collected during 1966 at various world sites; and the content of fallout /sup 137/Cs and /sup 90/Sr in samples of drinking water and milk collected in New York City through 1976. (CH)

  8. Chelating agents in pharmacology, toxicology and therapeutics

    The proceedings contain 71 abstracts of papers. Fourteen abstracts were inputted in INIS. The topics covered include: the effects of chelating agents on the retention of 63Ni, 109Cd, 203Hg, 144Ce, 95Nb and the excretion of 210Po, 63Ni, 48V, 239Pu, 241Am, 54Mn; the applications of tracer techniques for studies of the efficacy of chelation therapy in patients with heart and brain disorders; and the treatment of metal poisoning with chelating agents. (J.P.)

  9. Behaviour of solid fission products in the HTGR coated fuel particles

    Results of profile measurements for volume concentrations of 134,137Cs, 144Ce, 155Eu, 106Ru and fissionable material in the HTGR coated fuel particles which have been subjected to standard tests in the temperature range of 1273-2133 K and at burnup up to 17% fima are presented. Values of the effective coefficients of cesium diffusion in kern and protective coating of fuel particles which were subjected to standard in-pile tests in spherical fuel elements at the temperature of 1273 K and the burnup up to 15% fima as well as the value of relative release of solid fission products from the samples studied are given

  10. 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

    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

  11. Silviculture-ecological consequences of forest pollution due to radioactive effluents

    Radioactive contamination effect on the forest areas of Pripyat' Polessie is considered. Radiation processes in damaged pinetree plantations are characterized. Radionuclide migration dependent on soil types and tree stocks is analyzed. The data analysis has shown the evidence of 144Ce, 1'37Cs, 134Cs, 106Ru in 3 years after radioactive contamination in the controlled area. By the end of the third year a significant radionuclide migration had occurred between the forest floor and lower aquifers. refs. 2; figs. 2; tabs. 8

  12. Migration studies of radionuclides at the WIPP site

    A study was made of the effects on radionuclide migration from the solid TRU waste of inorganic and organic ligands in brine media. Typical organic waste meterials were exposed to synthetic brine at 700 for up to 1 year. Pure brine and brine/organic waste extracts were used to determine actinide and lathanide (153Gd, 144Ce, 152Eu, 243Am) distribution coefficients K/sub d/ between geological media and the brine. Results show that brine containing extract from plywood, etc. reduces considerably the K/sub d/

  13. Proposed Search for a Fourth Neutrino with a PBq Antineutrino Source

    Several observed anomalies in neutrino oscillation data can be explained by a hypothetical fourth neutrino separated from the three standard neutrinos by a squared mass difference of a few eV2. We show that this hypothesis can be tested with a PBq (ten kilocurie scale) 144Ce or 106Ru antineutrino beta source deployed at the center of a large low background liquid scintillator detector. In particular, the compact size of such a source could yield an energy-dependent oscillating pattern in event spatial distribution that would unambiguously determine neutrino mass differences and mixing angles.

  14. 1. Quarterly progress report 1984

    This report of the SCPRI exposes an interpretation of the principal results concerning the surveillance of radioactivity in the environment: atmospheric dusts, rainwater, surface water, underground water, sewage water, drinking water, food chain, sea water around nuclear plant sites and other sites. The activities of various radioisotopes are presented in tables (7Be, 54Mn, 58Co, 60Co, 90Sr, 95Nb, 106Ru, 110Ag, 125Sb, 131I, 134Cs, 137Cs, 144Ce, 226Ra, U, K, T and Rn). This report exposes also the state of surveillance and assistance operations on work sites and, the state of incidents along the three months; a bibliographic selection is also presented

  15. Hair as an indicator of the body burden of metals in relation to age

    Many factors influencing metal deposition in hair are still unknown. Animal experiments were performed to obtain data on the mechanism of transfer of elements into hair and to estimate whether hair retention is influenced by age, sex and chelating agent treatment. Experiments were performed on albino rats (Wistar strain) of different age and sex. Whole body hair (skin included) and organ retention of various elements was determined at different periods of time after intraperitoneal administration of the radioactive isotopes 115mCd, 203Hg, 54Mn, 59Fe, 65Zn, 141Ce, 137Cs, 203Pb and 85Sr. In some experiments DTPA was used for reducing body retention of 155mCd and 141Ce and DMPS for reducing 203Hg retention. Results show that hair and organ retention of elements in rats varies with age, sex and chelation treatment and such changes are specific for each element and can not be generalized. Age as a factor influencing hair retention of metals is likely to be more important for some elements than for others. In kinetic studies we found that due to differences in element distribution and kinetics, the relationship between hair and organ retention at various time intervals varies both with age and the element concerned. Sex influences not only hair but also metal retention and distribution in other organs. (author). 4 refs

  16. Passage of chromium-mordanted and rare earth-labeled fiber: time of dosing kinetics

    Coastal bermudagrass hay was labeled with Cr by the Cr-mordant procedure and with 177Lu applied to the same fiber. Neutral detergent fiber prepared from the same Coastal bermudagrass hay was labeled with Yb, 169Yb, Tb and 160Tb by soaking overnight following by thorough washing and drying. Wood chips were similarly labeled with Sm or La, and Solka Floc was labeled with 147Nd and 141Ce. The carriers, labels and times of administration to cattle were: bermudagrass fiber with both Cr and 177Lu, bermudagrass fiber with 169Yb and Solka Floc labeled with 147Nd at 0 h; bermudagrass fiber with Yb, Solka Floc with 141Ce and wood chips with Sm at 24 h; wood chips with La at 48 h; and bermudagrass fiber labeled with 160Tb at the beginning and labeled with Tb at the end of a meal. Fecal collection followed and passage characteristics were determined with a two-compartment, age-dependent model. Markers labeling the different fiber sources had different (P less than .01) passage rates (Solka Floc greater than Coastal bermudagrass greater than wood chips), but there was no difference within fiber source for rare earth passage. There also was no difference between the passage characteristics of Cr-mordant and 177Lu. However, passage rate of particles administered at the beginning of the meal (160Tb) was 42% higher than for particles at the end of the meal (Tb)

  17. Natural sorbents as barriers against migration of radionuclides from radioactive waste repositories

    The sorption properties of Bulgarian inorganic sorbents - clinoptilolite, vermiculite, bentonite, glauconite, celadonite and loess, which can be used as buffer, backfill and sealing materials in radwaste repository are studied. Experimental data about sorption and desorption capacities, radiation and thermal stability of sorbents from different Bulgarian deposits are reported and compared. Clinoptilolite from Beli Plast and its sodium variety from Kostino and Moryantsi is recommended as a barrier against radionuclide migration from radwaste repository due to their high sorption capacity of 137Ce, 90Sr and 60Co. The high selectivity of vermiculite for polyvalent ions (144Ce, 59Fe and 90Sr) gives grounds to include the sorption on vermiculite as a second step in the ion exchange technology for low level laundry waste decontamination. Bentonite is studied as a proposed buffer, backfill and sealing material. Its selectivity for cesium is lower compared to those of clinoptilolite. Thus a tailored-made mixture of bentonite and clinoptilolite will act as a barrier against radionuclides in different oxidation state. Glauconite can be successfully used as a barrier against migration of 144Ce, 90Sr, 54Mn and 65Zn. Loess is also included in the study, as the Kozloduy NPP is sited on loess formation and it is a natural potential site for low and intermediate level waste burial. It is concludes that zeolites and clays of Bulgarian deposits can be used effectively against radionuclide migration from radioactive waste repositories. 59 refs., 5 tabs. (author)

  18. Study of shortening of lifetime and of the occurrence of cancers in situ induced by cerium-144 hydroxide administered locally in various organs

    The authors compare the local action of 144Ce administered to rats in three different ways. Inhalation was chosen with a view to comparing the action of the β-emitter 144Ce with that of α-emitters such as plutonium and americium. Intramuscular injection was used to study the risk incurred through wounds contaminated by fission products, the purpose being to devise a model for the experimental study of osteosarcoma therapy. Oro-facial injection was selected in order to determine the carcinogenic effects of local irradiation in the sinuses and maxillaries. Here, too, it seemed useful to have a reproducible model of facial tumours that could be used for physiopathological and therapeutic studies. Cerium administered in hydroxide form and precipitating on the spot upon contact with living tissue gives local irradiation much greater than the dose delivered to other organs by the very slight fraction that diffuses. For these three modes of application the activities deposited in situ were varied, and for two of the three cases (intramuscular and intrafacial injection) the age of the animals at the moment of contamination was varied, too. The experiments brought out two principal effects: the appearance of local tumours, often cancerous, and a shortening of the animals' lifetime, the degree of the effect in both cases being linked to the dose. The experiments described here suggest that lifetime shortening and the presence of cancers in rats are separate phenomena, apparently independent of each other

  19. Gastrointestinal transit in the pig: measurement using radioactive lanthanides and comparison with sheep

    A technique to characterize the transit time of digesta through the gastrointestinal tract of the sheep has been described by Francois and Compere (1971). In the present paper, the authors present an adaptation of the method to the pig. On the first day of the experiment, each animal was given a diet uniformly labelled with 144Ce as an unabsorbable marker. The feces were collected at 1 or 2-hour intervals at progressively extended periods for the remainder of the collection period. The fecal concentration of the marker rose rapidly to a maximum, then decreased following a simple exponential law. Data were also expressed as a cumulative excretion curve of 144Ce. The mean retention time in the pig digestive tract could be calculated by concentration curves using either the m(t) parameter of Debouche (1974) or the t parameter proposed by Levenspiel (1974) to describe the flow of a fluid in an open vessel. The values obtained were identical to those found by Castle and Castle (1957) for the R parameter. These data are compared to those given by the same technique with the sheep

  20. Deadspace breathing as a screening test for early lung damage

    Breathing through added external deadspace (V/sub Dext/) was found to increase the tidal volume of normal dogs in order to achieve alveolar ventilation adequate for gas exchange. Addition of V/sub Dext/ did not alter alveolar-arterial gas gradients or cardiovascular function. Respiratory patterns during V/sub Dext/ breathing were compared with variables measured during treadmill exercise to investigate deadspace breathing as an indicator of early lung dysfunction caused by radiation pneumonitis in dogs. Dogs were evaluated clinically, radiographically and by pulmonary function tests at rest before and after inhaling 144Ce in fused aluminosilicate particles. By 4 mo after inhalation of 32 to 50 μCi/kg 144Ce, there were increases in respiratory frequency and minute volume during V/sub Dext/ breathing and in minute volume and the ventilatory equivalent for O2 while running. No other significant functional, radiographic or clinical changes were noted. The dogs were sacrificed and scattered foci of inflammation were found in their lungs. Deadspace testing detected early, subclinical lung alterations with a sensitivity and at a time identical to treadmill testing and did not require whole-body exercise or training

  1. Educational laboratory experiments on chemistry in a nuclear engineering school

    An educational laboratory experiment on radiochemistry was investigated by students in the general course of the Nuclear Engineering School of Japan Atomic Energy Research Institute. Most of them are not chemical engineers, but electrical and mechanical engineers. Therefore, the educational experiment was designed for them by introducing a ''word experiment'' in the initial stage and by reducing the chemical procedure as far as possible. It began with calculations on a simple solvent extraction process-the ''word experiment''--followed by the chemical separation of 144Pr from 144Ce with tri-n-butyl phosphate in a nitric acid system and then measurement of the radioactive decay and growth of the separated 144Pr and 144Ce, respectively. The chemical procedure was explained by the phenomenon but not by the mechanism of chelation. Most students thought the experiment was an exercise in solvent extraction or radiochemical separation rather than a radioactive equilibrium experiment. However, a pure chemist considered it as a sort of physical experiment, where the chemical procedure was used only for preparation of measuring samples. Another experiment, where 137Cs was measured after isolation with ammonium phosphomolybdate, was also investigated. The experiment eliminated the need for students who were not chemists to know how to use radioactive tracers. These students appreciated the realization that they could understand the radioactivity in the environmental samples in a chemical frame of reference even though they were not chemists

  2. Evaluation of fission product yields from fission spectrum n+239Pu using a meta analysis of benchmark data

    Chadwick, Mark B.

    2009-10-01

    Los Alamos conducted a dual fission-chamber experiment in the 1970s in the Bigten critical assembly to determine fission product data in a fast (fission neutron spectrum) environment, and this defined the Laboratory's fission basis today. We describe how the data from this experiment are consistent with other benchmark fission product yield measurements for 95,97Zr, 140Ba, 143,144Ce, 137Cs from the NIST-led ILRR fission chamber experiments, and from Maeck's mass-spectrometry data. We perform a new evaluation of the fission product yields that is planned for ENDF/B-VII.1. Because the measurement database for some of the FPs is small—especially for 147Nd and 99Mo—we use a meta-analysis that incorporates insights from other accurately-measured benchmark FP data. The %-relative changes compared to ENDF/B-VI are small for some FPs (less than 1% for 95Zr, 140Ba, 144Ce), but are larger for 99Mo (3%) and 147Nd (5%). We suggest an incident neutron energy dependence to the 147Nd fission product yield that accounts for observed differences in the FPY at a few-hundred keV average energy in fast reactors versus measurements made at higher average energies.

  3. Distribution of fission products in graphite sleeves and blocks of the ninth and tenth OGL-1 fuel assemblies

    Distribution of fission products in graphite sleeves and blocks of the ninth and tenth OGL-1 fuel assemblies was measured by gamma spectrometry with lathe sectioning. The assemblies were loaded with HTGR fuel compacts, which had been produced by a scaled-up facility for the High Temperature Engineering Test Reactor (HTTR) being developed by JAERI; and they were irradiated in an in-pile gas loop, OGL-1. Fission products detected in the sleeves were 137Cs, 134Cs, 155Eu, 154Eu, 144Ce, 125Sb and 110mAg. The last nuclide, however, may have been produced by activation of a stable isotope, 109Ag, contained as impurity. Effective retention capability of the sleeve was observed for 155Eu, 154Eu, 144Ce and 125Sb; while, not for 137Cs and 134Cs. Concentration of 137Cs in the graphite blocks was markedly higher at the downstream side than at the upstream side of the coolant. This was ascribed to migration of the nuclide with the coolant flow and its subsequent sorption on the surface of the block. (author)

  4. Il personaggio scontornato in Škola dlja Durakov. Dal romanzo di Saša Sokolov agli adattamenti teatrali

    Irina Marchesini

    2012-12-01

    Full Text Available Sokolov’s Shkola dlya Durakov (A School for Fools, 1976 is an extremely complex novel, which “depicts [the] world”, as D. Barton Johnson (1986:640[1] poignantly observes, “through the eyes, and pure, if eccentric, language, of a schizophrenic youth”. How is it possible to translate such linguistic features and the effects they create into another medium? This question lies at the core of my proposal, which aims to approach the problem of intermedial translation from prose to theatre through the presentation of an individual case-study. In fact, A School for Fools has been staged by the director Andrey Moguchy (Formalny Theatre, Saint Petersburg, Russia. With the intention of reproducing Sokolov’s aesthetic construction of illusion, Moguchy introduces a new genre in the theatrical context, the so-called “vizualnaya associaciya” (“visual association”. As the director explained in a recent interview, this original genre recalls the Impressionists’ position in observing and representing nature, in order to obtain the same effect generated by the reading of the novel. To comprehend this process better, special attention is devoted to the construction of unusual, hybrid characters, highlighting their constitutive features both in the novel and in the theatrical adaptation. Moreover, this research seeks to enrich discussion of the work of Sokolov and Moguchy. [1] Johnson, D. Barton (1986 “Sasha Sokolov's Twilight Cosmos: Themes and Motifs”, in: Slavic Review, 45, 4 (Winter 1986, pp. 639-649.

  5. Application of the brittle fracture technique (BFT) to homogenise biological samples and some observations regarding the distribution behaviour of the trace elements at different concentration levels in a biological matrix

    NAA was used to analyse K, P, Cl, Na, Fe, Zn, Rb, Mn, Se, Co, and Ag in bovine liver, before and after homogenization, using brittle fracture technique (BFT). The liver specimen analysed in this experiment did not present any extreme variation problem with respect to the trace element distribution profile in the liver matrix. Elaborate sample-handling and the possible influence of the interfering components such as resudial blood, blood vessels and fat on the concentration profile of the above mentioned elements are discussed. In another experiments using 60Co, 134Cs, 141Ce and 198Au radiotracers, the physical distribution of the added tracers following the process of biological matrix disintegration, for homogenization purposes was studied at 1 mg to 10 pg concentration levels. The results indicate that BFT is an efficient, clean and practical tool that meets the homogenization problems because of its suitability to practically all types of biomedical samples. (T.G.)

  6. Particle size distribution of aerosols during sand-blasting of steam turbines

    Studies were performed to determine the activity median aerodynamic diameter and the solubility classification of radioactive airborne particulates produced during sand blasting of steam turbines at Chin Shan Nuclear Power Station in Taiwan. Cascade impactors were used to collect air samples in the sand blasting house for analyses of particle size and elemental composition. Radionuclides identified in the samples included 60Co, 137Cs, 131I, 140Ba, 140La and 141Ce. These were found to have an activity median aerodynamic diameter of 3 μm to 4 μm, except for volatile 131I, which had a somewhat smaller diameter of 2.8 μm. The major elements composing the aerosols were Si, Fe, Ca, K, Al, and Cr. (author)

  7. 1975 progress report: Idaho National Engineering Laboratory site radioecology--ecology programs

    Results are reported from measurements of the content of various radionuclides in the tissues of wild animals on or near the Idaho National Engineering Laboratory sampled during 1975. Tissue samples from antelope, waterfowl, rodents, rabbits, and doves were analyzed for 13 radionuclides, including 134Cs, 137Cs, 95Zr, 95Nb, 103Ru, 238Pu, 239Pu, 90Sr, 131I, and 60Co which were responsible for the largest amounts of radioactivity. Measurements were also made of the content of 238Pu, 239Pu, and 241Am in soil samples and the radioactivity in tumbling weeds at the radioactive waste management site. Data are included from studies on the ecology of the pygmy rabbit, Salvilagus idahoensis, amphibians, reptiles, birds of prey, rodents, and coyotes, and vegetation in relation to land use at the site. Seasonal variations in the deposition and retention of 141Ce and 134Cs on sagebrush and bottlebrush grass were compared

  8. Germanium junction detectors. Theoretical and practical factors governing their use in radiation spectrometry

    Semi-conductor detectors have recently greatly increased the possibilities available to nuclear spectroscopists for the study of α, β and γ radiations. Their use in radio-chemistry has encouraged us to study their principle, their mechanism and also the conditions under which they can be used. The first part, which is theoretical, consists of a summary of what should be known concerning the best use of junction detectors, in particular Ge (Li) detectors. The second part, which is experimental, summarizes the laboratory work carried out over a period of one year on Ge (Li) detectors. Stress is laid on the possibilities presented by the use of these detectors as photo-electric spectrometers, and also on the precautions required. Amongst the numerous results presented, the resolution of 2.52 keV obtained for the γ radiation of 145.5 keV for 141Ce may be particularly noted. (authors)

  9. Studies on inorganic exchangers - manganese dioxide

    As a part of investigation of separation processes for long lived fission products from fuel reprocessing solution, manganese dioxide has been studied as an ion exchanger for cerium using 137Cs, 106Ru, 141Ce, sup(85,89)Sr, 95Zr and 95Nb as tracers. For different concentrations of HNO3, distribution ratios and breakthrough capacities were determined. Cerium was eluted by manganese sulphate and nitric acid. Results show that : (1) at all acidities cerium is adsorbed with almost no uptake of other rare earths, sodium, uranium and plutonium, (2) Ce (IV) gives better adsorption than Ce(III), (3) a combination of manganese sulphate (1 mg/ml) and 3M nitric acid elutes 99% cerium in 5-6 column volumes and (4) as for effect of absorption-elution cycles on MnO2 column, initially there is a decrease in capacity of cerium uptake but thereafter the capacity remains constant. (M.G.B.)

  10. Counting efficiency for radionuclides decaying by beta and gamma-ray emission

    In this paper, counting efficiency vs figure of merit for beta and gamma-ray emitters has been computed. It is assumed that the decay scheme has only a gamma level and the beta-ray emission may be coincident with the gamma-rays or the internal-conversion electrons. The radionuclides tabulated are: 20O, 20F, 28Al, 35P,41Ar, 42K, 47Se, 62Fe, 66Cu, 81Ge, 86Rb, 104Rh, 108Ru, 112Pd, 121Sn(m), 122In, 129I, 141Ce, 142Pr, 151Sm, 170Tm, 171Tm, 194Os, 203Hg, 205Hg, 210Pb, 225Ra, 244Am(m). It has been assumed that the liquid is a toluene based scintillator solution in standard glass vials containing 10 cm3. (Author)

  11. Development of a cosmic veto gamma-spectrometer

    Cosmic radiation contributes significantly towards the background radiation measured by a gamma-spectrometer. A novel cosmic veto gamma-spectrometer has been developed that provides a mean background reduction of 54.5%. The system consists of plastic scintillation plates operated in time-stamp mode to detect coincident muon interactions within an HPGe gamma-spectrometer. The instrument is easily configurable and provides improved sensitivity for radionuclides indicative of nuclear weapons tests and reactor incidents, including 140Ba, 95Zr, 99Mo, 141Ce, 147Nd, 131I, 134Cs and 137Cs. This has been demonstrated for Comprehensive Nuclear-Test-Ban Treaty applications to obtain the required 140Ba MDA of 24 mBq within 2 days counting. Analysis of an air filter sample collected during the Fukushima incident indicates improved sensitivity compared to conventional gamma-spectrometers. (author)

  12. (d,p) reactions on 124Sn, 130Te, 138Ba, 140Ce, 142Nd, and 208Pb below and near the Coulomb barrier

    The reactions 124Sn(d,p)125Sn, 130Te(d,p)131Te, 138Ba(d,p)139Ba, 140Ce(d,p)141Ce, 142Nd(d,p)143Nd, and 208Pb(d,p)209Pb have been investigated by measuring the differential cross sections of the (d,p) reactions and of the elastic scattering of deuterons at various incident energies below and near the Coulomb barrier. Using scattering potentials which describe the elastic scattering of the particles in the entrance and exit channels, reduced normalizations of 40 final states have been determined which are nearly independent of the uncertainties due to the ambiguities of optical potentials. The experimental errors are 8% on the average. In the energy region studied the expected constancy of derived spectroscopic factors is demonstrated

  13. Solvent extraction using tetracycline as complexing agent Pt. 14

    The behaviour of tetracycline as an extracting agent for Sr, I, Ba, Mo, Tc, Zr, Nb, Cs, Ru, Te and U was studied and the influence of the acidity of the aqueous phase upon extraction of the elements mentioned was examined. Experiments were made to determine whether the species extracted into the organic phase is the complex formed between tetracycline and the elements considered and to determine the time of shaking necessary so that the equilibrium between the phases is attained. As a practical application, the possibility of using the tetracycline-benzyl alcohol system for separating the fission products sup(137)Cs, sup(140)La, sup(141)Ce, sup(103)Ru, sup(95)Nb from each other and from uranium is presented. The same study was made for sup(131)I, sup(99m)Tc, sup(99)Mo, sup(132)Te, sup(239)Np and uranium and the steps necassary for the separation of these elements are proposed. (author)

  14. Nuclear Decay Data for the International Reactor Dosimetry Library for Fission and Fusion (IRDFF: Updated Evaluations of the Half-Lives and Gamma Ray Intensities

    Chechev Valery P.

    2016-01-01

    Full Text Available Updated evaluations of the half-lives and prominent gamma ray intensities have been presented for 20 radionuclides – dosimetry reaction residuals. The new values of these decay characteristics recommended for the IRDFF library were obtained using the approaches and methodology adopted by the working group of the Decay Data Evaluation Project (DDEP cooperation. The experimental data published up to 2014 were taken into account in updated evaluations. The list of radionuclides includes 3H, 18F, 22Na, 24Na, 46Sc, 51Cr, 54Mn, 59Fe, 57Co, 60Co, 57Ni, 64Cu, 88Y, 132Te, 131I, 140Ba, 140La, 141Ce, 182Ta, 198Au.

  15. Studies on inner bremsstrahlung from a few β-emitting isotopes

    Past experimental studies on the inner bremsstrahlung (IB) emission from the forbidden β transitions have shown marked deviations from the theoretical calculations of Lewis and Ford, Ford and Martin, Chang and Falkoff, Madansky and Gebhardt. In this paper we have re-analysed the data of IB emissions from four β-emitting isotopes, namely 89Sr, 141Ce, 111Ag and 99Tc, whose transitions are classified as forbidden. The raw experimental data already available in the literature are critically examined in the light of relevant statistics in order to arrive at meaningful conclusions. The unfolding of the IB spectra was done following the step-by-step procedure of Liden and Starfelt. The results obtained were different from those reported in the literature. (author)

  16. Seasonal variations in deposition and retention of cerium-141 and cesium-134 in cool desert vegetation

    Deposition velocities and retention half-times were measured for 141Ce and 134Cs aerosols on big sagebrush (Artemisia tridentata) and squirreltail bottlebrush (Elymus elymoides). These aerosols were released over a native community in southeast Idaho during each of three seasons -spring, summer, and winter -to study the effects of plant development and growth on deposition velocity and retention. Air concentrations during the release and vegetation concentration after the release were measured to determine deposition velocity. Friction velocity, roughness length, and particle size were measured to determine retention half-time. There was no significant difference between nuclides for deposition velocity and retention half-time. Species differences were significant (P -1 in spring, summer and winter, respectively. Big sagebrush values were 1.6, 1.6, and 1.0 mm s-1. Retention data indicated a rapid initial loss (half-times of 1-2 d) followed by a slower loss (half-times of several weeks). (Author)

  17. Electrodeposition of actinide traces from aqueous alkaline solutions and tributyl phosphate

    The electrodeposition of uranium and trace quantities of 239Pu, 234Th, 144Ce on a stainless steel disk was investigated from 0.5-2.0M NaOH and the two-phase system, extract of actinides in TBP-aqueous solution of NaOH. The electrodeposition yield of the above elements reaches 98-100% in 40 min of electrolysis with current density 0.4-0.5 A/cm2. The presence of 0.5M Na2CO3, 2.0M NaNO3, 2.0M NaNO2, 0.2M NaF in alkaline solutions does not decrease the electrodeposition yield. The electrodeposited films meet all the requirements of α-spectrometry. The uranium oxidation states (V) and (IV) were determined in the electrodeposited films. (author) 9 refs.; 3 figs.; 1 tab

  18. Methodology for the evaluation of decontaminant drugs at in vitro systems

    An experimental system was developed in order to facilitate hte study of the action of decontaminant drugs in hepatic tissue. Three stages are distinguished: 1) The isolation and the hepatocytes culture in the presence of a chelant agent. 2) The obtainment of the soluble cytoplasmic fraction and its chromatographyc analysis. 3) The comparison of the behaviour of the chelant agent in in vivo and in vitro of the mentioned fraction. 144CeCl was employed as a radionuclide and DTPA CaNa3 as a decontaminant agent. The preliminary results of the mechanism of action of the decontaminant obtained by chromatography shows a different distribution of the radionuclide between compounds of high and low molecular weight, in the hepatocytes incubated in the presence of the chelant concerning the controls. (M.E.L.)

  19. Development of a technology and a pilot plant for treatment of small volumes of liquid radioactive waste

    The development of technology for treatment of liquid radioactive waste is described. Waste arisings are estimated. Liquid wastes of concern are mainly low active wastes according to the Bulgarian legislation. The activity is determined by the presence of 134Cs, 137Cs, 60Co, 90Sr, 144Ce, 65Zc, 54Mn, 110mAg. Different precipitation processes are compared. The mixed iron hydroxide - calcium phosphate precipitation is determined as suitable for decontamination of the liquid radioactive waste. Effective decontamination is achieved when precipitation is followed by ion exchange. Additional increase of the decontamination is possible when sorbents are added during the precipitation step. The sorption and desorption of radionuclides on zeolites are studied. Cement solidification and thermal treatment of zeolites are studied for immobilization of radioactive material from precipitation and ion exchange. Both methods produce stable waste forms suitable for containment of the radionuclides. (author). 17 refs, 3 figs, 12 tabs

  20. Measurements of fission product concentrations in surface air at Bombay, India, during the period 1975-1981

    Measurements on airborne fallout radioactivity for the period 1975 up to the middle of 1981 are given. Normally, these measurements are confined to Bombay, but after nuclear tests, some of the other stations where these measurements were carried out in previous years are operated for some time to study the levels of fresh activity. The levels of the long-lived fission products 144Ce, 106Ru and 137Cs, and the short-lived fission products 95Zr and 140Ba, were measured, whenever they could be detected following nuclear tests, and tabulated. The data indicate that the activity varies by large factors from tests of similar yield, depending on the meteorological and other conditions. It was determined that the travel time for the Chinese test debris from Lop Nor, China to the West-coast of India is 14 to 16 days

  1. Preparative electrophoresis of industrial fission product solutions

    The aim of this work is to contribute to the development of the continuous electrophoresis technique while studying its application in the preparative electrophoresis of industrial fission product solutions. The apparatus described is original. It was built for the purposes of the investigation and proved very reliable in operation. The experimental conditions necessary to maintain and supervise the apparatus in a state of equilibrium are examined in detail; their stability is an important factor, indispensable to the correct performance of an experiment. By subjecting an industrial solution of fission products to preparative electrophoresis it is possible, according to the experimental conditions, to prepare carrier-free radioelements of radiochemical purity (from 5 to 7 radioelements): 137Cs, 90Sr, 141+144Ce, 91Y, 95Nb, 95Zr, 103+106Ru. (author)

  2. Game as a bioindicator of the radiocontamination

    Natural and artificially produced radionuclides were determined in meat and bones of deer, boar and wild hare on hunting areas in Vojvodina (Serbia). Seven natural radionuclides and three fission products (235U, 238U, 232Th, 7Be, 144Ce, 40K, 106Ru, 134Cs, 137Cs, 90Sr) were identified in the investigated game samples. The highest contents of the radionuclides were found in bones and meat of boars and the lowes in the bones of fallow-deer. The predominant radionuclides were 40K and 90Sr, for all of the investigated animals and their contents depended strongly upon the game species, organ type and the age of the animal. The examined breeding sites did not appear to have any effect on the radionuclide contents in game, which indicates that the radionuclides were uniformly distributed over the habitat. (author) 5 refs.; 3 tabs

  3. Calculated activities of some isotopes in the RA reactor highly enriched fuel significant for possible environmental contamination - Operational report

    This report contains calculation basis and obtained results of activities for three groups of isotopes in the RA reactor 80% enriched fuel element. The following isotopes are included: 1) 85mKr, 87Kr, 88Kr, 131J, 132J, 133J, 134J, 135J, 133Xe, 138Xe i 138Cs, 2) 89Sr, 90Sr, 91Sr, 92Sr, 95Zr, 97Zr, 103Ru, 105Ru, 106Ru, 129mTe, 134Cs, 137Cs, 140Ba, 144Ce, kao i 3) 238Pu, 239Pu i 240Pu. It was estimated that the fuel is exposed to mean neutron flux. The periodicity of reactor operation is taken into account. Calculation results are given dependent on the time of exposure. These results are to be used as source data for Ra reactor safety analyses

  4. Transuranic elements and strontium-90 in samples from forests in Poland

    Enhanced levels of non-volatile nuclides;141,144Ce, 95Zr, 95Nb, 103,106Ru, 238,239,240,241Pu, 241Am, 242,243,244Cm and 154,155Eu were observed in the samples from north-western Poland. This was considered to be a result of finding in sample ''hot particle''. Investigations conducted in the Institute of Nuclear Physics allowed us to conclude that on this area a non typical isotopic composition of Chernobyl fallout was very common. The enhanced activities (up to 100% above the global fallout value) of 90Sr, 238,239,240Pu and 241Am were observed. The presence of 243,244Cm and 154,155Eu was confirmed. It seems that the quasi-continuous fallout of huge numbers of small 'hot particles' occurred there from the high altitude radioactive cloud, which moved toward Scandinavia on 26-th of April, 1986. (author)

  5. Sorption of radionuclides from Pb-Bi melt. Report 1

    Results of laboratory investigations of sorption and interfacial distribution of 54Mn, 59Fe, 60Co, 106Ru, 125Sb, 137Cs, 144Ce, 154,155Eu and 235,238U radionuclides in the system Pb-Bi melt - steel surface are analyzed. It is shown that 106Ru and 125Sb are concentrated in Pb-Bi melt and other radionuclides with higher oxygen affinity are sorbed on oxide deposits on structural materials. Temperature dependences of sorption efficiency of radionuclides are studied. It is shown that there is sharp increase of this value for all radionuclides near the temperature range 350-400 deg C. Recommendations are given on the use of 106Ru and 125Sb as a reference for fuel element rupture detection system with radiometric monitoring of coolant melt samples and 137Cs, 134Cs, 134mCs with radiometric monitoring of sorbing samples

  6. Improved estimate of the cross section for inverse beta decay

    Ankowski, Artur M

    2016-01-01

    The hypothesis of the conserved vector current, relating the vector weak and isovector electromagnetic currents, plays a fundamental role in quantitative description of neutrino interactions. Despite being experimentally confirmed with great precision, it is not fully implemented in existing calculations of the cross section for inverse beta decay, the dominant mechanism of antineutrino scattering at energies below a few tens of MeV. In this article, I estimate the corresponding cross section and its uncertainty, ensuring conservation of the vector current. While converging to previous calculations at energies of several MeV, the obtained result is appreciably lower and predicts more directional positron production near the reaction threshold. These findings suggest that in the current estimate of the flux of geologically produced antineutrinos the 232Th and 238U components may be underestimated by 6.1 and 3.7%, respectively. The proposed search for light sterile neutrinos using a 144Ce--144Pr source is predi...

  7. Radiation-induced mesotheliomas in rats

    Mesotheliomas have been reported in rats that inhaled plutonium, but these tumors have not been extensively studied. To investigate a possible role for inhaled radionuclides in the induction of mesotheliomas, four life-span studies conducted at the Inhalation Toxicology Research Institute are reviewed. A total of 3076 F344 rats were exposed by inhalation to aerosols of 239PuO2, mixed uranium-plutonium oxide, or 144CeO2. Results showed that a low incidence of pleural mesotheliomas was induced by either alpha- or beta-emitting radionuclides deposited and retained in the lung. Chronic alpha irradiation was more effective per unit dose in producing mesotheliomas than chronic beta irradiation of the lung by a factor of 15. 7 refs., 1 tab., 7 figs

  8. Study on measurement of trace radioactivity, (2)

    The method was worked out so as to measure 59Fe, 60Co, 65Zn, 95Zr, and 144Ce successively from the same sample by ion-exchange separation. This method was also applicable to the measurement of 90Sr and 137Cs. It was confirmed that 131I in milk could be measured satisfactorily by the method of US Atomic Energy Commission, when raw milk before processing was preserved in good condition. 3H in natural water can be measured with a gas magnifying counter without isotope concentration when water is transformed into hydrogen gas. It was found that an external heater type reactor is desirable to transform 3H in water into methane gas so far as the repair is concerned. The present reactor needs some improvement, however, to get better yield as the best synthesizing yield for methane gas obtained so far was only 48.8%. (Kobatake, H.)

  9. Training of skin decontamination and its results

    In the nuclear power and radioisotope handling facilities, one of the most important problems is a radioactive contamination on skin. Hand skin contamination occurs very often in the operation area and such surface contamination must be removed as soon as possible to prevent an internal contamination. From 1967 to 1975, training courses for skin decontamination had been held with total 536 of trainee based on the radiation protection manual at the Oarai Research Establishment of JAERI. In the training courses, fresh pig skin samples used instead of human skin were contaminated with 137Cs, 131I, 85Sr, 60Co, 144Ce, 88Y, 239Pu, fission products and activated metal corrosion particles, respectively. These samples were washed practically by each trainee with the skin decontamination method recommended in the manual. Results obtained in the training showed that such training itself is a significant work and this skin decontamination method is an excellent first aid. (auth.)

  10. The Chernobyl fallout in Greece and its effects on the dating of archaeological materials

    The effects of the fallout from the nuclear reactor accident at Chernobyl have been monitored at various sites in Greece. Here we present the first estimates of gamma dose rates, an essential parameter in the dating of archaeological materials by thermoluminescence (TL) and ESR methods. The dose rates are derived from the long-lived radionuclides of 137Cs, 134Cs, 106Ru and 144Ce (with t1/2 ≥ 1 yr). The present dose rates vary between 30 and 60 mrad/yr, but maximum values of around 811 mrad/yr have also been recorded, for ground-surface exposures. These dose rate values must be regarded as very significant to TL and ESR dating of samples from now on and a correction factor should be applied. (orig.)

  11. The risk of liver tumors in dogs and man from radioactive aerosols

    Life-span studies in progress using beagle dogs that inhaled relatively soluble or relatively insoluble forms of radionuclides will provide information from which we may project the risk to humans for liver cancer from inhaled radioactive material. Twenty-two liver tumors have been observed in dogs exposed to beta-emitting radionuclides, mainly 144Ce, and one liver tumor in a dog exposed to 238Pu. Two liver cancers were also observed in control dogs. The risk of liver cancer in dogs that inhaled beta-emitting radionuclides was calculated to be 90 liver cancers per million rads. The risk of liver cancers in dogs in our studies and in studies at the University of Utah, when compared to the incidence of liver tumors in humans exposed to Thorotrast, suggest that the risk of liver cancer from an inhaled beta-emitting radionuclide in people is about 30 liver cancers per million person-rads. 19 refs., 3 tabs

  12. Critical pathway studies for selected radionuclides. Part of a coordinated programme on environmental monitoring for radiological protection in Asia and the Far East

    The programme carried out critical pathway studies for selected radionuclides (60Co, 63Ni, 59Fe, 54Mn, sup(110m)Ag, 106Ru and 144Ce) and assessed population exposure in the vicinity of Tarapur Atomic Power Station. The following topics are covered under the programme. (i) Demographic study of dietary habits and consumption data for Tarapur population. (ii) Concentration and accumulation of radionuclides in food products. (iii) Determination of radionuclides in sea water, silt, marine algae and marine organisms at Tarapur Atomic Power Station (TAPS) Site. (iv) Behaviour of radionuclides released to marine environment. (v) Evaluation of critical exposure pathway. (vi) Population exposure in the vicinity of Tarapur Atomic Power Station

  13. Measurement of leached hulls

    Leached hulls are the short lengths of fuel rod cladding and fuel element hardware which constitute a major waste product of a reprocessing plant employing a chop-and-leach head-end process. The small, undissolved fuel residue (0.1 to 1.0% of original fuel content) which is discarded with this waste must be measured for safeguards, material accountability, and process control reasons. This report gives a critical analysis of hull measurement techniques involving the analysis of fission product gamma rays, spontaneous fission neutrons from curium, and delayed neutron activation. Major emphasis is given to the measurement of 2186-keV gamma rays from 144Ce--144Pr. A detailed description of typical leached hull characteristics is presented at the beginning of the report. An extensive review of experience gained from existing hull measurement systems in the United Kingdom, France, Japan, Germany, Italy, and the United States is presented

  14. Batch extraction studies for the recovery of 233U from thoria irradiated in PHWR

    Batch equilibrium studies were carried out to optimise the extraction parameters for the recovery of 233U from thoria irradiated in PHWR. The thorium concentration and the acidity of the feed was adjusted to ca. 100 g/l and 4 M nitric acid respectively. The concentration of uranium was in the range of 1.4 g/L and it contained long lived fission product like 144Ce-144Pr, 134Cs, 137Cs, 106Ru-106Rh, 105Eu, 154Eu, 90Sr-90Y and 125Sb. 3% TBP in dodecane was used as the solvent. Four stages of batch extraction was followed by a single scrub stage of 4 M nitric acid. The scrubbed organic was stripped with 0.01 M HNO3 thrice. The stripped product was concentrated by evaporation and passed through a cation exchanger to remove the residual thorium. The results of the studies are discussed in detail. (author)

  15. Application of the radiochemical - and the direct gamma ray spectrometry method to the burnup determination of irradiated uranium oxide

    The burn up of natural U3O8 that occurs by the action of thermal neutrons was determined, using the radioisotopes 144Ce, 137Cs, 103Ru, 106Ru and 95Zr as monitors. The determination of the burn up was made using both destructive and non-destructive methods. In the non-destructive method, the technique of direct gamma-ray spectrometry was used and the radioisotopes mentioned were simultaneously counted in a Ge-Li detector. In the radiochemical method the same radioisotopes were isolated one from the other and from all other fission products before counting. The solvent extraction technique was used for the radiochemical separation of uranium, cerium, cesium and ruthenium. To separate zirconium and niobium, adsorption in silica-gel was used. The extraction agent employed to isolate cesium was dipycrilamine and for the separation of the other radioisotopes Di-(2-Ethyl Hexyl) Phosphoric acid (HDEHP) was used. (Author)

  16. Fixation of {gamma}-radionuclides by the PVA-PMAA system

    Won, Hui Jun; Ahn, Byung Gil; Jung, Chong Hun; Kim, Gye Nam; Oh, Won Zin [KAERI, Taejon (Korea, Republic of)

    2000-06-01

    A series of laboratory experiments was conducted to investigate the fixation characteristics of poly(vinylalcohol)-poly(methacrylic)(PVA-PMAA) mixed solution on the soluble {gamma}-radionuclides. Using the potentiometric titration technique, it was found out that the PVA and PMAA in a solution form inter macromolecular complex. The mobilized portion of each radionuclide by water from sand surface treated with a fixative was measured by {gamma}-ray spectroscopy. The mobilized portion of minor radionuclides such as {sup 241}Am, {sup 154}Eu, {sup 155}Eu and {sup 144}Ce were higher than those of {sup 134}Cs and {sup 137}Cs. The capability of PVA-PMAA system was better among the candidate solutions for the fixation of total {gamma}-radioactivity. {sup 134,137}Cs which is composed of more than 85 percent of total {gamma}-radioactivity could be fixed effectively by the PVA-PMAA solution. (author)

  17. Fixation of γ-radionuclides by the PVA-PMAA system

    A series of laboratory experiments was conducted to investigate the fixation characteristics of poly(vinylalcohol)-poly(methacrylic)(PVA-PMAA) mixed solution on the soluble γ-radionuclides. Using the potentiometric titration technique, it was found out that the PVA and PMAA in a solution form inter macromolecular complex. The mobilized portion of each radionuclide by water from sand surface treated with a fixative was measured by γ-ray spectroscopy. The mobilized portion of minor radionuclides such as 241Am, 154Eu, 155Eu and 144Ce were higher than those of 134Cs and 137Cs. The capability of PVA-PMAA system was better among the candidate solutions for the fixation of total γ-radioactivity. 134,137Cs which is composed of more than 85 percent of total γ-radioactivity could be fixed effectively by the PVA-PMAA solution. (author)

  18. Measurement by γ spectrometry of specific activities of radioisotopes present in vegetal ashes. Study of variations of the ambient radioactivity level in the Grenoble transverse valley from March 1966 to August 1968

    The first part of this report addresses the dosimetry of γ emitting radio-elements which are present in vegetal samples. The dose measurements were performed by spectrometry and results were processed by using a least square method. The second part reports works performed in the Grenoble transverse valley by using the same techniques. Radioactivity fluctuations of various radio-elements (40K, 54Mn, 95Zr + 95Nb, 103Ru + 106Rh, 137Cs, 137Ba, 140Ba + 140La, 144Ce + 144Pr) in various vegetal species, in water and in sediments have been monitored in seven points of the Isere river banks, upstream and downstream the city of Grenoble, from March 1966 to August 1968. Fluctuations observed for each radio-element are explained by comparison with physiologic, hydrologic and atmospheric climate conditions. The principles of a systematic control of a site for the detection of possible radioactive pollutions are then defined

  19. Radiation accidents on human in the nuclear installations and their medical emergency procedures, (1)

    Present nuclear installations are one of the safest installations among industrial facilities, being equipped with various safety instruments. Since X-ray was discovered in 1895, however, many radiation injuries of various degrees and kinds occurred. Among dangerous nuclides often observed as radioactivity pollutions in nuclear installations, the exposure to β-ray such as 90Sr, 106Ru, 95Zr, 131I, 144Ce, etc, is considered to be serious problems. When they affect wounds or are inhaled into lungs, only symptomatic treatment is practicable at present, and usually nothing can be depended upon, but spontaneous eliminating ability. As the mass inhalation of α nuclides, especially transuranium nuclides, is quite dangerous, the treatment by lung-irrigation now under development is most effective as the emergency treatment. When trans-uranium nuclides were accidentally observed from wounds, they should be eliminated by the injection of chelating agent. (Kobatake, H.)

  20. Influence of the complexones on the ionic transfer through cell membranes and the level of radionuclides-metals accumulation in water plants

    The influence of the complexones diethylenetriaminepentaacetic acid (DTPA), ethylenediaminetetraacetic acid (EDTA) and hydroxyethylidenediphosphonic acid (HEDP) with relatively low concentrations (from 0.1 to 50 mg/l) on ionic permeability of cell membranes of Nitellopsis obtusa algae, as well as on the accumulation levels of the radionuclides 144Ce, 106Ru, 90Sr and 137Cs in different species of water plants has been studied. It has been shown that complexones under study (with the concentrations up to 50 mg/l) may reduce accumulation levels of three- and four-valent metals and their radionuclides in water plants. For the plants in natural as well as in artificial nutrient medium, however, the complexones increase the availability of metals, forming with the readibly soluble, mobile complex compounds

  1. Radionuclides in plankton from the South Pacific Basin

    We have initiated an investigation of the utility of marine plankton as bioconcentrating samplers of low-level marine radioactivity in the southern hemisphere. A literature review has shown that both freshwater and marine plankton have trace element and radionuclide concentration factors (relative to water) of up to 104. We participated in Operations Deepfreeze 1981 and 1982, collecting a total of 48 plankton samples from the USCGC Glacier on its Antarctic cruises. Battelle Pacific Northwest Laboratories sampled air, water, rain, and fallout. We were able to measure concentrations in plankton of the naturally-occurring radionuclides 7Be, 40K, and the U and Th series, and we believe that we have detected low levels of 144Ce and 95Nb in seven samples ranging as far south as 680. Biological identification of the plankton suggests a possible correlation between radionuclide concentration and the protozoa content of the samples. 7 references, 5 figures

  2. Fission product release from ZrC-coated fuel particles during postirradiation heating at 1600 C

    Release behavior of fission products from ZrC-coated UO2 particles was studied by a postirradiation heating test at 1600 C (1873 K) for 4500 h and subsequent postheating examinations. The fission gas release monitoring and the postheating examinations revealed that no pressure vessel failure occurred in the test. Ceramographic observations showed no palladium attack and thermal degradation of ZrC. Fission products of 137Cs, 134Cs, 106Ru, 144Ce, 154Eu and 155Eu were released from the coated particles through the coating layers during the postirradiation heating. Diffusion coefficients of 137Cs and 106Ru in the ZrC coating layer were evaluated from the release curves based on a diffusion model. 137Cs retentiveness of the ZrC coating layer was much better than that of the SiC coating layer. ((orig.))

  3. 4. Quaterly progress report 1983

    This report of the SCPRI exposes an interpretation of the principal results concerning the surveillance of radioactivity in the environment: atmospheric dusts, rainwater, surface water, underground water, sevrage water, drinking water, food chain, sea water around nuclear plant sites and other sites. The activities of various radioisotopes are presented in tables (7Be, 58Co, 60Co, 75Se, 103Ru, sup(110m)Ag, 124Sb, 125Sb, 134Cs, 137Cs, 144Ce, 90Sr, 95Nb, 106Ru, 226Ra, 54Mn, U, K and T). This report exposes also the state of surveillance and assistance operations on work sites and, the state of incidents along the three months; a bibliographic selection is also presented

  4. Identification of levels in neutron-rich 145Ce and 147Ce nuclei

    High-spin structures in the neutron-rich nuclei 145Ce and 147Ce produced in the spontaneous fission of 252Cf have been investigated by prompt γ-ray spectroscopy. A collective band structure in 145Ce is identified. Several sidebands along with the new high-spin states in 147Ce are also identified. Particle-plus-rotor model calculations indicate that the yrast bands in 145Ce and 147Ce most probably originate from coupling of the νi13/2 orbital to the ground states of 144Ce and 146Ce. The ground state configurations of 145,147Ce are (νh9/2+νf7/2) and νh9/2, respectively. (c) 1999 The American Physical Society

  5. A study of radionuclide transfer between invertebrates and their marine sedimentary environment

    Exchanges between sediment and marine organisms were studied in some benthic marine invertebrates, especially Arenicola marina L. (an Annelid). Experiments were carried out on the transfer of 60Co, 137Cs and accessorily 59Fe and 144Ce. Water was the chief vector for benthic marine invertebrates. These invertebrates seemed to act mainly in sedimentary areas on the redistribution of adsorbed radionuclides within the sediment. Radioactive contamination of the invertebrates was affected by various physiological or ecological factors. Benthic marine invertebrates were then studied as links in food chains. The transfer of 60Co was studied in three food chains or fractions of food chains. The procedure allowed interesting observations from the health protection point of view and more fundamental investigations on cobalt metabolism (regulation, excretion) in a mollusc, a crustacea and a teleost

  6. Recent Borexino results and prospects for the near future

    D'Angelo, D; Benziger, J; Bick, D; Bonfini, G; Avanzini, M Buizza; Caccianiga, B; Cadonati, L; Calaprice, F; Cavalcante, P; Chavarria, A; Chepurnov, A; Davini, S; Derbin, A; Empl, A; Etenko, A; von Feilitzsch, F; Fomenko, K; Franco, D; Galbiati, C; Gazzana, S; Ghiano, C; Giammarchi, M; Goeger-Neff, M; Goretti, A; Grandi, L; Hagner, C; Hungerford, E; Ianni, Aldo; Ianni, Andrea; Kobychev, V; Korablev, D; Korga, G; Kryn, D; Laubenstein, M; Lehnert, B; Lewke, T; Litvinovich, E; Lombardi, F; Lombardi, P; Ludhova, L; Lukyanchenko, G; Machulin, I; Manecki, S; Maneschg, W; Manuzio, G; Meindl, Q; Meroni, E; Miramonti, L; Misiaszek, M; Mosteiro, P; Muratova, V; Oberauer, L; Obolensky, M; Ortica, F; Otis, K; Pallavicini, M; Papp, L; Perasso, L; Perasso, S; Pocar, A; Ranucci, G; Razeto, A; Re, A; Romani, A; Rossi, N; Saldanha, R; Salvo, C; Schoenert, S; Simgen, H; Skorokhvatov, M; Smirnov, O; Sotnikov, A; Sukhotin, S; Suvorov, Y; Tartaglia, R; Testera, G; Vignaud, D; Vogelaar, R B; Winter, J; Wojcik, M; Wright, A; Wurm, M; Xu, J; Zaimidoroga, O; Zavatarelli, S; Zuber, K; Zuzel, G

    2014-01-01

    The Borexino experiment, located in the Gran Sasso National Laboratory, is an organic liquid scintillator detector conceived for the real time spectroscopy of low energy solar neutrinos. The data taking campaign phase I (2007 - 2010) has allowed the first independent measurements of 7Be, 8B and pep fluxes as well as the first measurement of anti-neutrinos from the earth. After a purification of the scintillator, Borexino is now in phase II since 2011. We review here the recent results achieved during 2013, concerning the seasonal modulation in the 7Be signal, the study of cosmogenic backgrounds and the updated measurement of geo-neutrinos. We also review the upcoming measurements from phase II data (pp, pep, CNO) and the project SOX devoted to the study of sterile neutrinos via the use of a 51Cr neutrino source and a 144Ce-144Pr antineutrino source placed in close proximity of the active material.

  7. Search for Sterile Neutrinos with a Radioactive Source at Daya Bay

    Dwyer, D A; Littlejohn, B R; Vogel, P

    2011-01-01

    The far site detector complex of the Daya Bay reactor experiment is proposed as a location to search for sterile neutrinos with > eV mass. Antineutrinos from a 500 kCi 144Ce-144Pr beta-decay source (DeltaQ=2.996 MeV) would be detected by four identical 20-ton antineutrino targets. The site layout allows flexible source placement; several specific source locations are discussed. In one year, the 3+1 sterile neutrino hypothesis can be tested at essentially the full suggested range of the parameters Delta m^2_{new} and sin^22theta_{new} (90% C.L.). The backgrounds from six nuclear reactors at >1.6 km distance are shown to be manageable. Advantages of performing the experiment at the Daya Bay far site are described.

  8. Lifetime tumor risk coefficients for beagle dogs that inhaled cerium-144 chloride

    Boecker, B.B.; Hahn, F.F.; Griffith, W.C. [and others

    1995-12-01

    Reported here is one of the life-span radionuclide toxicology studies being conducted at ITRI in Beagle dogs. These studies are examining the life-span health risks of inhaled {Beta}-, {gamma}- and {alpha}-emitting radionuclides to expand available knowledge on these risks especially for the many cases for which human data are not available. The outcomes of these studies are providing important information on dosimetry and dose-response relationships for these inhaled radionuclides and the relative importance of a broad range of dose- and effect-modifying factors. A number of these studies are currently coming to completion. Much of the ITRI effort is being directed to final reviews of the dosimetric, clinical, and pathologic results and writing summary manuscripts. Radiation doses and effects in tissues adjacent to bone, specifically those of epithelial or marrow origin, should be considered when determining risks from internally deposited, bone-seeking radionuclides such as {sup 144}Ce.

  9. Toxicity of inhaled beta-emitting radionuclides: an experimental approach

    An experimental approach to evaluation of the toxicity of inhaled beta-emitting radionuclides in laboratory animals is described. These radionuclides are being studied in both relatively soluble (90SrCl2, 144CeCl3, 91YCl3 or 137CsCl) and relatively insoluble aerosol forms (90Y, 91Y, 144Ce or 90Sr in fused aluminosilicate particles). Initial lung or whole-body radionuclide burdens were selected to result in early deaths due to severe lesions at the highest exposure levels, and more subtle changes, such as neoplasia, at the lower levels. The organs affected vary depending on the solubility and chemical characteristics of the isotope. For radionuclides inhaled in relatively soluble forms, long-term effects have been seen in the liver, skeleton, respiratory tract and other tissues. In contrast, long-term effects seen in the dogs exposed to relatively insoluble forms have been mainly associated with the lung and contiguous tissues. In all experiments, emphasis is placed on an evaluation of the influence of radiation dose rate and total dose on the resulting dose-response relationship. Over the mid-range of exposure levels, it will be possible to compare the radiation dose and biological response relationships for the several radioactive aerosols with their different radiation dose patterns. These studies with young adult dogs are complemented with comparable studies in other species (mice, rats and Syrian hamsters) and with animals of different ages (immature, aged). This basic approach, with emphasis on factors that alter the resulting radiation dose pattern, offers the maximum likelihood of meeting the continuing, and not always predictable, needs for information on the toxicity of inhaled beta-emitting radionuclides that may be encountered in nuclear industry operations

  10. Toxicity of inhaled beta-emitting radionuclides: an experimental approach

    An experimental approach to evaluation of the toxicity of inhaled beta-emitting radionuclides in experimental animals is described. Graded levels of these radionuclides are being studied in both relatively soluble (90SrCl2, 144CeCl3, 91YCl3, 137CsCl) and relatively insoluble forms (90Y, 91Y, 144Ce and 90Sr in fused clay particles). Initial lung or whole-body activity burdens were selected to result in early deaths due to severe lesions at the highest levels, deaths at later times with moderate to marked pathologic changes and more subtle changes such as neoplasia at the lower levels. The organs affected vary depending on the solubility and chemical characteristics of the isotope. For radionuclides inhaled in relatively soluble forms, long-term effects have been seen in the liver, skeleton, and other tissues in addition to some pulmonary effects. In contrast, long-term effects seen in the dogs exposed to relatively insoluble forms have been mainly associated with the lung and contiguous tissues. In the latter experiments, emphasis is placed on an evaluation of the influence of radiation dose rate and total dose on the resulting dose-response relationship. Over the mid-range of the relationship between radiation dose and biological response, it will be possible to compare the relationships for the several radioactive aerosols with their different radiation dose patterns. These studies with young adult dogs are complemented with comparable studies in other species (mice, Syrian hamsters) and with animals of different ages (immature, aged). This basic approach, with emphasis on factors that alter the resulting radiation dose pattern, offers the maximum likelihood of meeting the continuing, and not always predictable, needs for information on the toxicity of inhaled beta-emitting radionuclides that may be encountered in nuclear industry operations. (U.S.)

  11. Studies of the coagulation flotation of bentonite and its application to the removal of Co2+ ions and fission products, Ce and Eu

    The regions of dispersion, coagulation precipitation, coagulation flotation, and redispersion were determined for aqueous bentonite-cationic surfactant and bentonite-cationic surfactant-polyacrylamide(PAA) systems. The region of coagulation flotation was markedly extended by the addition of PAA to both the lower and higher concentration regions of the cationic surfactant, hexadecyldimethylbenzylammonium chloride(HDBAC), and to the lower concentration region of bentonite. The phenomenon of coagulation flotation was investigated in detail and was applied to the removal of Co2+ ions and nuclear fission products, 144Ce and 155Eu, from an aqueous solution. The composition of the reagents for the maximum efficiency of bentonite flotation corresponded to that of the maximum efficiency of Co2+-ion flotation. The effect of the pH on the flotation efficiency was studied in particular. The maximum flotation efficiency of 96% was obtained at pH 11 for Co2+ ions, 86% at pH 9.7 for 144Ce, and 93% at pH 10.5 for 155Eu. These radioactive elements were almost completely adsorbed on the surface of bentonite particles and were floated with them in the pH region of the maximum flotation efficiency. It was confirmed that Co2+ ions could be floated also from an extremely low concentration (10-9 mol/l) of Co2+ ions with nearly the same efficiency of flotation and with the additives in the same condition. Co2+ ions could also be effectively removed by using the step-by-step flotation, showing as high a flotation efficiency as 99.8%. (auth.)

  12. Radiocaesium forms in soil - problems of experimental determination

    A method for determining Cs form in soil is proposed based on the comparison of the experimental data on desorption of Cs radionuclide from the soil contaminated as a result of the Chernobyl accident and from the soil samples on which Cs was absorbed in laboratory (Cs was introduced in ionic form in solution). The data obtained on desorption of Cs from different soils show that Cs radionuclide is present in the soil contaminated as a result of the Chernobyl accident predominantly in an ionic form (sorbed on the different soil fractions). It has also been found that the ratio of 144Ce/137Cs radionuclides is much higher in solution than in the soil. At the same time the data on sorption of Cs and Ce radionuclides on different soils from solution 0.1M HCI + 0.1M KCI + 0.1M FeCI3 show that the sorption ability of Cs is higher than the sorption ability of Ce for all the soil types investigated. Hence, it can be assumed that the mechanism of the radionuclides extraction is desorption rather than dissolution of the matrix particles, since in the letter case extraction value of the radionuclides would not be different. The fact that the ratio of 144Ce/137Cs radionuclides in solution remains higher than in soil independent on the distance from the Chernobyl NPP indicates that the form of the radionuclides does not change with the distance from the reactor. In order to determine what type of molecules Cs radionuclide can be bound to in soil the experiments on sorption of Cs on sandy soil in the presence of humic acid in solution has been carried out. The data obtained show that the presence of humic acids has none or little effect on the sorption of Cs. This indicates that interaction of Cs radionuclides with humic acid is week and these molecules can not be responsible for binding Cs in soil. (author)

  13. Concentration and depuration of some radionuclides present in a chronically exposed population of mussels (Mytilus edulis)

    Factors are described which affect the concentration (p Ci g-1 dry wt) and loss of 241 Am, 239+240Pu, 238Pu, 144Ce, 137Cs, 134Cs, 106Ru, 95Zr and 95Nb in an exposed population of mussels Mytilus edulis L. from Ravenglass on the Esk estuary, Cumbria, UK which receives radioeffluents from the British Nuclear Fuels Ltd. (BNFL) plant at Sellafield, some 10 km to the north. Tidal position and mussel body size have a negligible influence on the concentration of 241Am, 137Cs and 106Ru in the total soft tissue, but variation in soft tissue weight throughout the year has a considerable influence on the apparent concentration and depuration times of these radionuclides. Apart from the clearance (tsub(1/2) biol, 1 to 3 h) of sediment-associated activity from the digestive tract, the depuration rate profiles follow a single component clearance curve with a biological half-life in excess of 200 d for 241 Am, 239+240Pu, 238Pu and 144Ce, and of 40 d for 137Cs. The clearance of 106Ru is more complex and consists of a 3 component depuration profile with biological half-lives of 6 h, 12 d and 260 d. The depuration profiles presented in this work are for chronically ingested isotopes under natural conditions; acute exposure will most likely result in different profiles, especially those derived from laboratory spiking experiments. Isotope ratio data support the hypothesis that the main route of entry into the mussel for the majority of the radionuclides studied is from the water. (orig./WL)

  14. EML Surface Air Sampling Program, 1990--1993 data

    Larsen, R.J.; Sanderson, C.G.; Kada, J.

    1995-11-01

    Measurements of the concentrations of specific atmospheric radionuclides in air filter samples collected for the Environmental Measurements Laboratory`s Surface Air Sampling Program (SASP) during 1990--1993, with the exception of April 1993, indicate that anthropogenic radionuclides, in both hemispheres, were at or below the lower limits of detection for the sampling and analytical techniques that were used to collect and measure them. The occasional detection of {sup 137}Cs in some air filter samples may have resulted from resuspension of previously deposited debris. Following the April 6, 1993 accident and release of radionuclides into the atmosphere at a reprocessing plant in the Tomsk-7 military nuclear complex located 16 km north of the Siberian city of Tomsk, Russia, weekly air filter samples from Barrow, Alaska; Thule, Greenland and Moosonee, Canada were selected for special analyses. The naturally occurring radioisotopes that the authors measure, {sup 7}Be and {sup 210}Pb, continue to be detected in most air filter samples. Variations in the annual mean concentrations of {sup 7}Be at many of the sites appear to result primarily from changes in the atmospheric production rate of this cosmogenic radionuclide. Short-term variations in the concentrations of {sup 7}Be and {sup 210}Pb continued to be observed at many sites at which weekly air filter samples were analyzed. The monthly gross gamma-ray activity and the monthly mean surface air concentrations of {sup 7}Be, {sup 95}Zr, {sup 137}Cs, {sup 144}Ce, and {sup 210}Pb measured at sampling sites in SASP during 1990--1993 are presented. The weekly mean surface air concentrations of {sup 7}Be, {sup 95}Zr, {sup 137}Cs, {sup 144}Ce, and {sup 210}Pb for samples collected during 1990--1993 are given for 17 sites.

  15. Characterization of gaseous and particulate effluents from the nuclear vitrification project

    Samples were taken during the second high-level liquid waste vitrification campaign associated with the NWVP. Sample analysis established the following total average emission levels in the undiluted vitrification off-gas stream: 3H - 1.2 μCi/m3, 14C - 0.2 μCi/m3, 129I - 1 nCi/m3, NO/sub x/ - 0.5%, 99Tc - 1.6 pCi/m3, and γ-emitters - 105(γ/s)/m3. The aerosol size distribution is composed almost entirely of particles exhibiting smaller diameters than the minimum value for which absolute filters are rated, with an empirical geometric mean diameter of 0.13 μm and a particle mass concentration of 84.7 pg/cm3. The particulate matter was composed of 106Ru, 125Sb, /sup 125m/Te, 134Cs, 137Cs, 144Ce, 154155Eu and 241Am. The particulate emission levels in the undiluted process off-gas stream were: 106Ru - 44 nCi/m3, 125Sb - 0.52 nCi/m3, /sup 125m/Te - 1.7 nCi/m3, 134Cs - 7.8 nCi/m3, 137Cs - 52 nCi/m3, 144Ce - 0.8 μCi/m3, 154Eu - 0.3 nCi/m3, 155Eu - 0.18 nCi/m3, and 241Am - 0.19 nCi/m3. All these environmental gaseous and airborne emissions level liquid waste were well within PNL waste management guidelines

  16. Cycling of radionuclides and impact of operational releases in the near-shore ecosystem off the west coast of India

    Radioecology of the near-shore environment was investigated at Bombay and Tarapur on the west coast of India. The major radionuclides released from the processing plant at Bombay were 137Cs, 144Ce and 106Ru and were discharged through a pipeline to Bombay Harbour bay. At Tarapur the major radionuclides discharged were 131I, 134Cs, 137Cs and 60Co. After dilution with condenser-coolant sea water, releases were carried out through open channels along the shoreline to the sea. Studies on radionuclide cycling in clam-bed sediment, the indicator type benthic organism Anadara granosa, and the fish gobiid mudskipper in Bombay Harbour bay showed that the effective half-life of 137Cs is short compared with the physical half-life (30 years). This is attributable to the desorption of 137Cs from sediment and the fact that the benthic organism readily equilibrates with its environment. The dose to the benthic organism was calculated to be about 0.06 to 3μGy/h. Desorption of 144Ce and 106Ru was not observed. Investigations at Tarapur showed the effective distribution of radionuclides in sea water, sediment, seaweed and marine organisms. It was observed that the radionuclides discharged were mainly confined to a region 2 km from the outfall. The highest activity found in these matrices was only 7% of the derived maximum permissible concentration. The highest thyroid dose due to 131I by fresh seafood intake was 3% of the permissible dose and the highest whole-body dose due to other radionuclides was only 1% of the permissible dose. (author)

  17. EML Surface Air Sampling Program, 1990--1993 data

    Measurements of the concentrations of specific atmospheric radionuclides in air filter samples collected for the Environmental Measurements Laboratory's Surface Air Sampling Program (SASP) during 1990--1993, with the exception of April 1993, indicate that anthropogenic radionuclides, in both hemispheres, were at or below the lower limits of detection for the sampling and analytical techniques that were used to collect and measure them. The occasional detection of 137Cs in some air filter samples may have resulted from resuspension of previously deposited debris. Following the April 6, 1993 accident and release of radionuclides into the atmosphere at a reprocessing plant in the Tomsk-7 military nuclear complex located 16 km north of the Siberian city of Tomsk, Russia, weekly air filter samples from Barrow, Alaska; Thule, Greenland and Moosonee, Canada were selected for special analyses. The naturally occurring radioisotopes that the authors measure, 7Be and 210Pb, continue to be detected in most air filter samples. Variations in the annual mean concentrations of 7Be at many of the sites appear to result primarily from changes in the atmospheric production rate of this cosmogenic radionuclide. Short-term variations in the concentrations of 7Be and 210Pb continued to be observed at many sites at which weekly air filter samples were analyzed. The monthly gross gamma-ray activity and the monthly mean surface air concentrations of 7Be, 95Zr, 137Cs, 144Ce, and 210Pb measured at sampling sites in SASP during 1990--1993 are presented. The weekly mean surface air concentrations of 7Be, 95Zr, 137Cs, 144Ce, and 210Pb for samples collected during 1990--1993 are given for 17 sites

  18. Sediment-seawater distribution coefficient for radionuclides and estimation of radionuclide desorption ratio from soil in seawater

    Soil can migrate to the sea through river systems by weathering; radionuclides sorbed on the soil could migrate together to the sea. In the terrestrial environment, soil is in contact with freshwater; however, after it reaches the sea, large amounts of high-salinity seawater can contact with the soil. Consequently, some radionuclides as well as stable elements would be released from the soil. To estimate the potential extractability of radionuclides from soil, the solid/liquid distribution coefficient, Kd, was used in this study. Since there were no reported Kd values for sediments in Japanese estuarine areas, the published global fallout 60Co, 90Sr, 137Cs and 144Ce activity concentration data in estuarine areas in Japan were collated first. Data suitable for obtaining Kd for sediment-seawater values were identified. The geometric means of the Kd values for 60Co, 90Sr, 137Cs and 144Ce were 1200, 23, 200 and 2000, respectively. Using the Kd differences between the terrestrial and estuarine environments, the extractability of these radionuclides from soil to seawater was estimated. Stable element concentration data for Japanese soil and estuarine sediments were also used for comparisons. It was found that the extraction of Co and Ce from soil would be negligible; however, Sr and Cs would be partially removed from the soil to the seawater. For Cs, a preliminary study on 137Cs extractability from soil in seawater was carried out. The data supported a possible Cs extraction from Cs contaminated soil in estuarine systems, which might affect the biota living in the systems. (author)

  19. The accumulation of radionuclides by Dreissena polymorpha molluscs - The Accumulation of Radionuclides from Water and Food in the Dreissena polymorpha Mollusks

    Jefanova, O.; Marciulioniene, D. [Nature Research Centre, Akademijos str. 2, LT-08412 Vilnius, Lietuva (Lithuania)

    2014-07-01

    The specific activity of {sup 137}Cs, {sup 60}Co, {sup 54}Mn, {sup 90}Sr was measured in mollusks Dreissena polymorpha samples from lake Drukshiai that is the cooling pond of the Ignalina NPP. Item the accumulation of {sup 137}Cs, {sup 90}Sr, {sup 144}Ce, {sup 106}Ru in the mollusks from water and from phytoplankton which is a part of their diet was evaluated under laboratory conditions. The data of long-term (1991-2009) studies conducted at six monitoring stations of lake Drukshiai show that in 1991 {sup 137}Cs in mollusks Dreissena polymorpha was found only in that lake's area which was influenced by the effluent that got into lake from the industrial drainage channel of Ignalina NPP. In later periods of the investigation the {sup 137}Cs specific activity was detected in mollusks samples which had been collected at other monitoring stations (the aquatory of lake Drukshiai). Meanwhile {sup 60}Co and {sup 54}Mn in Dreissena polymorpha were detected only in that lake's area which was impacted by the industrial drainage channel. The data of long-term investigation show that the major amount of radionuclides has come into lake Drukshiai through the industrial drainage system of Ignalina NPP. Albeit {sup 137}Cs, {sup 90}Sr, {sup 144}Ce, {sup 106}Ru get into the mollusks through a large amount of the water rather than from the food (phytoplankton), therefore the food can also be the main source of radionuclides in the organism of these mollusks in aquatic environment when there are low levels of specific activities of these radionuclides. (authors)

  20. Studies on influence of biological factors on concentration of radionuclides

    Biological factors influencing the concentration of radionuclides were studied from the points of uptake through digestive tract, food as pathways, and metabolic activities. The uptake of radionuclides by marine fishes through digestive tract was determined by whole body counter. 137Cs, 65Zn, 131I, 54Mn, 60Co, 85Sr, and 144Ce were used as tracers and was given with solid feed. The feed given was excreated 24 to 48 hours later in small of middle sized fishes, and 20 to 48 hours later in large sized fishes. The uptake rate of 137Cs and 65Zn was high absorption of 20 to 80 per cent, that of 131I, 60Co and 54Mn was not remarkable, and that of 85Sr and 144Ce was low absorption. The biological concentration of 137Cs through pathways of food. In fishes taking up radionuclides through contaminated food, concentration factor increased in accordance with contamination level. In addition, radionuclides with small uptake but delayed excretion and those with high concentration rate could be the factors to decide the concentration factors of marine organisms. In order to study the relationship between metabolic activities and concentration, the uptake of one-year old fishes and adult fishes, and fishes fed and those non-fed were compared. One-year fishes took up large amount of 85Sr during short period, however, concentration by metabolism in adult fishes was slow. Comparing feeding group and non-feeding group, the former showed 85Sr concentration factor of 1.5 to 2 times that of the later, and the later showed 137Cs concentration factor of 2 to 4 times that of the former. However, both uptake and excretion were rapid suggesting that taking food activated the metabolism of substances. (Kanao, N.)

  1. Chromatographic purification of neutron capture molybdenum-99 from cross-contaminant radionuclides

    Technetium-99m is called the work horse, for many reasons, in nuclear medicine diagnostic purposes. It is produced as the β-decay of 99Mo radionuclide. Molybdenum-99 gel type generators are considered as a suitable alternative of the conventional chromatographic alumina columns loaded with fission molybdenum-99. 99Mo neutron-capture is cross-contaminated with radionuclides originated from activation of chemical impurities in the Mo target such 60C0, 65Zn, 95Zr, 175Hf, 181Hf, 86Rb, 134Cs, 141Ce, 152Eu, 140La,51Cr, 124Sb,46Sc, 54Mn, 59Fe and / or fast neutrons interactions with the stable isotopes of molybdenum such as 92mNb, 95Nb and 95Zr. To prevent contamination of the eluted 99mTc, successive purification methods were made. After complete dissolution of the irradiated target wrapped with thin Al foil in 5 M NaOH solution, hydrogen peroxide was added to start precipitation of Fe(OH)3. The formed Fe (III) minerals allow complete elimination of some radio contaminants from the molybdate solute such as 152Eu, 140La,141Ce, 45Mn and 92mNb in addition to partial elimination of 46Sc, 60Co and 59Fe radionuclides. The remaining supernatant was acidified by concentrated nitric acid to ph 9.5 for precipitation of Al(OH)3 with complete elimination of radio contaminants such as 95Zr 175Hf, 181Hf, 65Zn, 124Sb, 51Cr, 46Sc, 60Co and 59Fe. 134Cs and 86Rb radionuclides were not affected by precipitation of Fe(OH)3 or Al(OH)3. Chromatographic column of potassium nickel hexacyanoferrate (II) (KNHCF) has high affinity towards elimination of 134Cs and 86Rb radionuclides. Highly pure molybdate-99Mo solution was processed for preparation of zirconium molybdate gel generator with 99mTc eluate of high radionuclidic, radiochemical and chemical purity suitable for use in medical purposes.

  2. Geochemical studies of sorption and transport of radionuclides in rock media

    Four studies, which supported the goals of the WISAP Program at Battelle PNL, were undertaken by the Lawrence Livermore Laboratory during FY 1979. These were: (1) Batch K/sub d/ experiments, (2) Dynamic sorption experiments on rock cores, (3) Feasibility study for an in situ tracer test at the Climax Stock, NTS, and (4) Geochemical equilibrium code development. Only the equilibrium code development was not funded by the WISAP during FY 1979. The emphasis for the batch K/sub d/ studies was on various (15) sandstones in brine using 75Se, 85Sr, 125Sb, 137Cs, 141Ce, and 237Pu tracers. These sandstone samples were well-characterized for their physical and mineralogical nature. Complex K/sub d/ behavior was observed for the radionuclides studied but 85Sr showed K/sub d/ values near zero for all samples. Both 141Ce and 239Pu K/sub d/ values ranged from 20 to upper limits of greater than or equal to 17,000. Dynamic sorption studies were done on NTS tuff and St. Peter sandstone core using 3H, 85Sr, and /sup 95m/Tc. These radionuclides were injected as a short pulse into the rock-equilibrated water that was flowing through the core. Tracer-free water was then continually flowed through the core until elution curves for the mobile radionuclides were established. Tritium and /sup 95m/Tc both traveled through the cores at the same rate, indicating no sorption for the mobile fraction of /sup 95m/Tc (95TcO4-). Strontium-85 did not exit the tuff cores but did exit the sandstone core although the elution curves showed definite retardation relative to the movement of 3H and /sup 95m/Tc. Post-elution sectioning of the cores indicated that a fraction of the /sup 95m/Tc remained in the cores and was evenly distributed through the tuff cores. Strontium-85 showed a generally decreasing distribution from the inlet side to the outlet side of the tuff cores

  3. Health risks from radionuclides released into the Clinch River

    The purpose of this work is to estimate off-site radiation doses and health risks (with uncertainties) associated with the release of radionuclides from the X-10 site. Following an initial screening analysis, the exposure pathways of interest included fish ingestion, drinking water ingestion, the ingestion of milk and meat, and external exposure from shoreline sediment. Four representative locations along the Clinch River, from the White Oak Creek Embayment to the city of Kingston, were chosen. The demography of the lower Clinch River supplied information dealing with land use that aided in the determination of sites on which to focus efforts. The locations that proved to be the most significant included Jones Island at Clinch River Mile (CRM) 20.5, Grassy Creek and K-25 (CRM 14), Kingston Steam Plant (CRM 3.5), and the city of Kingston (CRM 0). These areas of interest have historically been and are still primarily agricultural and residential areas. Reference individuals were determined with respect to the pathways involved. The primary radionuclides of interest released from the X-10 facility into the Clinch River via White Oak Creek were identified in the initial screening analysis as 137Cs, 90Sr, 60Co, 106Ru, 144Ce, 131I, 95Zr, and 95Nb. Of these radionuclides, 137Cs, 60Co, 106Ru, 90Sr, 144Ce, 95Zr, and 95Nb were evaluated for their contribution to the external exposure pathway. This study utilized an object-oriented modeling software package that provides an alternative to the spreadsheet, providing graphical influence diagrams to show qualitative structure of models, hierarchical models to organize complicated models into manageable modules, and intelligent arrays with the power to scale up simple models to handle large problems. The doses and risks estimated in this study are not significant enough to cause a detectable increase in health effects in the population. In most cases, the organ does are well below the limits of epidemiological detection (1 to 30

  4. Characteristics of particulate radionuclides in the atmospheric surface layer of the 30-km zone of Chernobyl

    For the inhalation dose assessment, reliable estimations are necessary of the average volume concentration of particle bound radionuclides in the atmosphere specifying the nuclide composition, the activity distribution in the different particle size ranges and the solubility characteristics of the nuclides. For that purpose, the analysis of measurement series is presented of the daily average activity concentrations of 137Cs and 144Ce and their temporal and spatial variability. From 1986 till 1994, samples were taken with high-volume samplers and multicascade impactors; the number concentrations of aerosol particles and the number concentrations of 'hot' particles were determined for different conditions with an Aerosol Particle Sizer and a Rotating Arm Impactor. The data demonstrate a decrease the atmospheric concentrations of 137Cs and 144Ce with time larger than caused by radioactive decay alone. A statistical analysis showed a high level of fluctuations in the concentration of radionuclides in air with maxima exceeding the annual average by 10 to 20 times. The analysis of 88 experimental radioactivity size distributions at Zapolie and Pripyat for winddriven resuspension conditions have shown that the measured distributions are generally very wide and differ from the log-normal distribution in the most cases. At Zapolie, the mean air concentrations of 137Cs, discriminated in four size ranges, showed an increasing part of inhalable particles with time since the accident. In 1993, the inhalable fraction was about 48% of the total concentration. The size distribution of atmospheric 137Cs particulate activity during these periods of enhanced resuspension showed a similar common shape with two maxima, the first in the 2-4 μm range, and the second in the 12-20 μm range. The estimated radioactive loading of particles showed an enrichment of resuspended radionuclides compared with soil particles. The highest enrichment factor was found for large particles, the lowest

  5. Determination of uranium fission products interference factors in neutron activation analysis; Determinacao de fatores de interferencia de produtos de fissao de uranio na analise por ativacao neutronica

    Ribeiro Junior, Ibere Souza

    2014-09-01

    Neutron activation analysis is a method used in the determination of several elements in different kinds of matrices. However, when the sample contains high U levels the problem of {sup 235}U fission interference occurs. A way to solve this problem is to perform the correction using the interference factor due to U fission for the radionuclides used on elemental analysis. In this study was determined the interference factor due to U fission for the radioisotopes {sup 141}Ce, {sup 143}Ce, {sup 140}La, {sup 99}Mo, {sup 147}Nd, {sup 153}Sm and {sup 95}Zr in the research nuclear reactor IEA-R1 on IPEN-CNEN/SP. These interference factors were determined experimentally, by irradiation of synthetic standards for 8 hours in a selected position in the reactor, and theoretically, determining the epithermal to neutron fluxes ratio in the same position where synthetic standards were irradiated and using reported nuclear parameters on the literature. The obtained interference factors were compared with values reported by other works. To evaluate the reliability of these factors they were applied in the analysis of studied elements in the certified reference materials NIST 8704 Buffalo River Sediment, IRMM BCR- 667 Estuarine Sediment e IAEA-SL-1 Lake Sediment. (author)

  6. Inorganic oxides as alternative in the separation of non fissioned residual uranium

    The Al2O3, SiO2 and SnO2 as well as vegetable carbon have been studied for its possible use as sorbent in the concentration and separation of non fissioned residual uranium of some fission products such as: 141 Ce, 134 Cs, 125 Sb, 103 Ru, 95 Zr, 95 Nb of alkaline aqueous systems. The separation efficiency has been evaluated using natural uranium and radionuclides in static and dynamic processes, through liquid scintillation and gamma spectrometry. Therefore Al2O3, SiO2, SnO2 and carbon were pre-treated thermic and chemically and characterized through the technique of Nitrogen absorption analysis, X-ray diffraction and IR spectroscopy. By means of the p H determination and the aqueous system potential the present hydrolysis products were determined. The inorganic oxides show structural and surface changes due to the treatment. The adsorption process is realized by different mechanism depending of the sorbent. The results show that the retention capacity is a dependence of the oxides pre-treatment and of the hydrolysis products in the aqueous system, as well as of the experimental conditions. Not in this way for carbon in which the results show the treatment and the experimental conditions significantly have not influence in its adsorption capacity. (Author)

  7. VIP and its homologous increase vascular conductance in certain endocrine and exocrine glands

    The effects of vasoactive intestinal peptide (VIP) and related structural homologues on tissue vascular conductances were investigated in anesthetized male rats. VIP, peptide histidine isoleucine (PHI), secretin, growth hormone-releasing factor (GHRF), gastric inhibitory peptide (GIP), or saline was infused intravenously over 4 min. Tissue blood flows were measured during this time by use of 141Ce-labeled microspheres. Circulating thyrotropin (TSH), triiodothyronine (T3), and thyroxine (T4) levels were determined before and at 20 min and 2 h after treatment. Marked increases in thyroid, pancreatic, and salivary gland vascular Cs occurred during peptide infusion with the order of potency correlating with the degree of structural homology to VIP. PHI and secretin produced maximal increases in vascular Cs, which were the same as those obtained with VIP. Circulating TSH, T3, and T4 levels were not different from values in saline-infused rats after peptide treatments that caused striking increases in thyroid vascular C. These observations indicate that the vascular beds of certain endocrine and exocrine glands are responsive to the vasodilatory action of VIP and related homologues with the order of potency corresponding to the degree of structural homology to VIP. These results are also consistent with the proposal that structural homologues of VIP act at the same vascular receptor as VIP. Alternative, the involvement of different vascular receptors, acting through the same mechanism at a level beyond the receptor site, cannot be excluded

  8. Influence of gamma irradiation on conductivity of YBa2Cu3O7

    Manjunatha, H. C.

    2015-08-01

    We report a study on influence of gamma irradiation on conductivity of YBa2Cu3O7. We have measured the mass attenuation coefficient, effective atomic number, electron density and electrical conductivity for various gamma sources of energy ranging from 0.084 MeV to 1.330 MeV (170Tm, 57Co, 141Ce, 203Hg, 51Cr, 113Sn, 22Na, 137Cs, 60Co, 22Na and 60Co). The measured values agree with the theoretical values. The values of these parameters have been found to change with energy and interaction of gamma. We find evidence for a variation of the electrical conductivity of YBa2Cu3O7 with the irradiated photon energy and this variation is shown in figures up to 105 MeV. The variations of effective atomic number and electron density with energy are shown graphically for all photon interactions. Conductivity found to vary with the energy of the irradiated gamma radiation and interaction process of gamma. This kind of studies is important in the field of superconductivity.

  9. Transfer of radionuclides from maternal food to the fetus and nursing infants of minipigs

    Transfer of 110mAg, 58Co, 59Fe, 141Ce, 103Ru, 88Y, 85Sr, 51Mn, 134Cs, 152Eu, 95mTc, 75Se, 65Zn and 133Gd was investigated in utero and during lactation in minipigs given the radioactive material added to food from day 50 of pregnancy until the end of lactation. The paper presents selected results on Ag, Co, Fe, Sr, Mn, Cs, Ru and Y and Tc. Transfer was highest for Cs and, in haemopoietic tissues, for Fe. Lower transfer was found for Ag, Fe, Mn with some preference for certain tissues (Ag in brain and liver, Mn in pancreas). Sr accumulated almost exclusively in bone and Tc in thyroid with higher concentrations in fetal and infant tissues than in maternal tissues. Lanthanides, Ru and Y were all close to detection limits or below in most maternal or fetal or infant tissues and could be found in bone and, less consistently, in kidney and liver. (author)

  10. Study on the method for determination of the nuclear fuel elements burnout by the quantitative analysis of 148Nd

    The scope of present work to study the precision and accuracy of a method for separation and determination of the.stable isotope 148Nd. The extraction chromatography and ion exchange techniques were used for the separation of fission products and uranium. Kieselguhr and di(2-ethyl-hexyl)phosphoric acid were used as inert support and stationary phase, respectively, in the steps of the separation procedure where the extraction chromatography technique was applied, and anionic resin mixed with Pb02 was used for the ion exchange operation. The behaviour of each element in the separation procedure was verified by means of radioactive tracers, namely, 147Nd, 141Ce and 137Cs. Use was made of the thermal neutron activation analysis in order to determine the 148Nd percentage recovered after the separation procedure was run. On the other hand, the radioactive isotope 147Nd was used to find chemical yield achieved for the separation procedure. Student's t test applied to verify the accuracy of the method used whose acceptability was verified by using the criterion recommended by McFarren and also taking into account the suggestion proposed by Eckschlager. The precision of the method was verified by means of the standard deviation of the several determinations. (author)

  11. Effects of vasoactive intestinal peptide on vascular conductance are unaffected by anesthesia

    In rats anesthetized with ketamine and pentobarbital (KET/PB), vasoactive intestinal peptide (VIP) increases vascular conductance (VC) in the salivary gland, pancreas, and thyroid gland, whereas no changes in VC are observed in a number of other organs. Because anesthesia may alter the responsiveness of physiological systems, we compared the effects of VIP on organ VC in conscious or anesthetized rats. Chronically catheterized rats were studied in the conscious state or 30 min after induction of anesthesia with KET/PB, isoflurane, or Inactin. Blood flows were measured by the reference sample version of the radioactive microsphere (MS) technique using two MS injections (141Ce-MS/85Sr-MS). Mean arterial blood pressure was monitored and used in the calculation of VC. Organ VCs were similar under basal conditions in conscious and anesthetized rats. VIP infusion caused systemic hypotension and increased VCs in the salivary gland, pancreas, and thyroid gland, and these responses were largely unaffected by anesthesia. These results indicate that the anesthetics used do not alter basal VC or the responsiveness of the vasculature to exogenous VIP

  12. Application of inorganic exchangers in fission product separation

    Synthetic ion exchangers ammonium phosphomolybdate/phosphotungstate (APW), polyantimonic acid (PA) and manganese dioxide have been investigated for separation of cesium, strontium and cerium respectively with a view to their use in fission product separation. Their breakthrough capacities and elution characteristics were determined using 137Cs, sup(85,89)Sr and 141Ce as tracers. Results indicate that : (1) Cs adsorbed on APW is easily eluted with 3M NH4NO3 at a temperature of 500C with an overall yield of 90% in about 10 column volumes, (2) strontium adsorbed on PA is completely eluted by 1M AgNo3 + 8M HNO3 at room temperature and (3) manganese sulphate (1 mg/ml) + 3M HNO3 elutes cerium adsorbed on manganese dioxide. Column characteristics (exchange capacity and flow rate) are not affected upto 6 cycles of sorption-elution. Based on these findings, a scheme of separation of fission products from waste solution is proposed. Pu uptake on PA is found to be governed by U/Pu ratio in the solution. The ratio > 104 inhibits the uptake. Pu on PA is eluted in 10 column volumes by 0.01M ascorbic acid +2M nitric acid. The exchange PA can be used over 20 cycles of sorption-elution. (M.G.B.)

  13. Solvent extraction study on the separation of molybdenum-99 and uranium in sulfuric acid solution by tri-n-octylamine in kerosene

    The basic extraction study on the separation of fission product molybdenum-99 and uranium in sulfuric acid solution by tri-n-octylamine (TOA) in kerosene has been investigated. The equilibration time and the effect of temperature, concentration of extractant, uranium and sulfuric acid concentration on this extraction system were examined. The optimum conditions for the coextraction of molybdenum-99 and uranium have been obtained with the overall recovery of 90% for 99Mo and greater than 99% for uranium. Based on the complex stability difference between UO2(VI) and MoO2 (VI) with TOA, uranium in the organic phase can be back-extracted by proper chloride concentration. On the other hand, molybdenum-99 can be stripped from the organic phase by sodium carbonate or ammonium hydroxide solution. Decontamination factors of some major fission products such as 95Zr, 95Nb, 103Ru, 132Te, 141Ce and 131I in the separation process were also examined in this report. 11 references, 8 figures, 2 tables

  14. Interim environmental monitoring report for the Nevada test site, first quarter 1981

    During the first calendar quarter of 1981, no radioactivity from the nuclear tests conducted at the Nevada Test Site was measured offsite by the US Environmental Protection Agency's Environmental Monitoring Systems Laboratory. Low concentrations of 95Zr, 95Nb, 103Ru, and 141Ce attributed to the People's Republic of China nuclear test of October 15, 1980, were detected in air samples throughout the Air Surveillance Network. The maximum concentrations of these radionuclides were less than 0.1 percent of the Concentration Guides. The dosimeters of fixed station at Complex I (Coal Valley) indicated an exposure of 1.6 mR, and the dosimeters of two offsite residents, one living at Glendale, Nev., and the other near Complex I, (Coal Valley) appeared to have net exposures of 3.1 mR and 3.2 mR, respectively; however, further evaluation revealed that the net exposures were not due to an exposure from NTS operations, but may be a statistical anomaly related to an unusually low variation in the environmental background exposure rate. Further investigation is in progress

  15. Inorganic oxides as alternative in the separation of non fissioned residual uranium; Oxidos inorganicos como alternativa en la separacion del uranio residual no fisionado

    Baca G, A

    1997-07-01

    The Al{sub 2}O{sub 3}, SiO{sub 2} and SnO{sub 2} as well as vegetable carbon have been studied for its possible use as sorbent in the concentration and separation of non fissioned residual uranium of some fission products such as: {sup 141} Ce, {sup 134} Cs, {sup 125} Sb, {sup 103} Ru, {sup 95} Zr, {sup 95} Nb of alkaline aqueous systems. The separation efficiency has been evaluated using natural uranium and radionuclides in static and dynamic processes, through liquid scintillation and gamma spectrometry. Therefore Al{sub 2}O{sub 3}, SiO{sub 2}, SnO{sub 2} and carbon were pre-treated thermic and chemically and characterized through the technique of Nitrogen absorption analysis, X-ray diffraction and IR spectroscopy. By means of the p H determination and the aqueous system potential the present hydrolysis products were determined. The inorganic oxides show structural and surface changes due to the treatment. The adsorption process is realized by different mechanism depending of the sorbent. The results show that the retention capacity is a dependence of the oxides pre-treatment and of the hydrolysis products in the aqueous system, as well as of the experimental conditions. Not in this way for carbon in which the results show the treatment and the experimental conditions significantly have not influence in its adsorption capacity. (Author)

  16. Assessments of circulatory changes in the scalded skin of rats using radioactively labelled microspheres

    In this study, changes in dermal circulation occurring in scalded rats were to be obtained with the aid of 141Ce-labelled microspheres. Prior to the tests, scalds were artificially produced to meet the standards prescribed for lesions of grades I, IIb and III. The comparative group was made up of rats, the dorsal skin of which had been treated with DMSO. In all animals, parallel measurements were carried out to assess the circulation of the intact abdominal skin. The highest values were obtained in DMSO-treated animals, with those determined for rats of the grade IIb group being only marginally lower. In animals showing first-degree lesions the blood supply of the dorsal skin was poor at 5 min following traumatisation, even though values were seen to rise again after 10 min. Extremely low circulatory values were measured in rats showing third-degree scalds. The findings revealed here matched the data obtained by other methods on changes in dermal circulation caused by scalds. (orig./MG)

  17. Feasibility of the instrumental neutron activation analysis of entire archaeological pottery. Part 1: Precision of the results and radiological safety of the process

    The feasibility of the instrumental neutron activation analysis of entire pieces of archaeological pottery, using low thermal neutron fluxes, is examined. The study takes into account the chemical elements relevant for archaeological investigations, as well as the degree of accuracy required for such kind of research. It is shown that after irradiation of a typical pottery sample of about 1 kg during 45 minutes, at a thermal flux of about 109 n.cm-2.s-1, analytical signals are obtained, by gamma spectrometry, with counting statistics better than 1%, for 76As, 131Ba, 141Ce, 60Co, 134Cs, 181Hf, 140La, 24Na, 122Sb, 46Sc, 153Sm and 233Pa, whereas 51Cr, 152Eu, 42K, 86Rb, 175Yb and 65Zn can be detected with counting statistics within 1% and 2%. On the other hand, the statistics of measurement are relatively poor (orders of 3% - 10%) for 177Lu, 147Nd, 239Np, 160Tb and 181Ta. The feasibility of accomplishment reliable quantitative determinations, taking into account the complexity of the analysis of entire pieces of archaeological pottery is discussed, which involves factors such as high masses, as well as asymmetric and variable shapes. (orig.)

  18. Determination of uranium fission products interference factors in neutron activation analysis

    Neutron activation analysis is a method used in the determination of several elements in different kinds of matrices. However, when the sample contains high U levels the problem of 235U fission interference occurs. A way to solve this problem is to perform the correction using the interference factor due to U fission for the radionuclides used on elemental analysis. In this study was determined the interference factor due to U fission for the radioisotopes 141Ce, 143Ce, 140La, 99Mo, 147Nd, 153Sm and 95Zr in the research nuclear reactor IEA-R1 on IPEN-CNEN/SP. These interference factors were determined experimentally, by irradiation of synthetic standards for 8 hours in a selected position in the reactor, and theoretically, determining the epithermal to neutron fluxes ratio in the same position where synthetic standards were irradiated and using reported nuclear parameters on the literature. The obtained interference factors were compared with values reported by other works. To evaluate the reliability of these factors they were applied in the analysis of studied elements in the certified reference materials NIST 8704 Buffalo River Sediment, IRMM BCR- 667 Estuarine Sediment e IAEA-SL-1 Lake Sediment. (author)

  19. Intestinal circulation during inhalation anesthesia

    This study was designed to evaluate the influence of inhalational agents on the intestinal circulation in an isolated loop preparation. Sixty dogs were studied, using three intestinal segments from each dog. Selected intestinal segments were pumped with aortic blood at a constant pressure of 100 mmHg. A mixture of 86Rb and 9-microns spheres labeled with 141Ce was injected into the arterial cannula supplying the intestinal loop, while mesenteric venous blood was collected for activity counting. A very strong and significant correlation was found between rubidium clearance and microsphere entrapment (r = 0.97, P less than 0.0001). Nitrous oxide anesthesia was accompanied by a higher vascular resistance (VR), lower flow (F), rubidium clearance (Cl-Rb), and microspheres entrapment (Cl-Sph) than pentobarbital anesthesia, indicating that the vascular bed in the intestinal segment was constricted and flow (total and nutritive) decreased. Halothane, enflurane, and isoflurane anesthesia were accompanied by a much lower arteriovenous oxygen content difference (AVDO2) and oxygen uptake than pentobarbital or nitrous oxide. Compared with pentobarbital, enflurane anesthesia was not accompanied by marked differences in VR, F, Cl-Rb, and Cl-Sph; halothane at 2 MAC decreased VR and increased F and Cl-Rb while isoflurane increased VR and decreased F. alpha-Adrenoceptor blockade with phentolamine (1 mg . kg-1) abolished isoflurane-induced vasoconstriction, suggesting that the increase in VR was mediated via circulating catecholamines

  20. A seasonal comparison of deposition velocities and retention half-times for Cs-134 and Ce-141 on cool desert vegetation

    Due to a scarcity of reliable deposition velocity estimates for radionuclides (particularly those in the submicron range) pooled estimates have been used to predict population doses resulting from atmospheric releases of radioactive particulates. The use of these estimates has led to large uncertainties in whole body dose estimates. Deposition velocities and retention half-times were therefore determined for submicron aerosols of 141Ce (biologically inactive) and 134Cs (biologically active) on sagebrush dominated desert vegetation in SE Idaho. Approximately 250 mCi (9.3 GBq) of each radionuclide were released over stands of Artemisia tridentata (big sagebrush) and bottlebrush grass (Sitanion hystrix) during three stages of plant development - spring vegetative growth, seed development, and plant dormancy. Air filters and vegetation samples were collected immediately following each release for use in deposition velocity calculations. Vegetation sampling was continued for a period of three months to obtain retention data. Deposition velocity values were 0.20 cm/s for sagebrush and 0.025 cm/s for grass. The loss of activity on the vegetation seemed to best fit a two component exponential loss function. Short component half-times were 1 to 2 days for both species. Long component half-times were two to three weeks for the shrub species and one to two weeks for the grass species. No significant difference was observed between nuclides. (author)

  1. Selective extraction of trivalent actinides from lanthanides using dicyclohexyldithiophosphinic acid and tributylphosphate

    In a previous study we showed that the three dithiophosphinic acids: dicyclohexyldithio-phosphinic acid (HDCHDTP), diphenyldithiophosphinic acid (HDPhDTP), and bis(2,4,4-trimethylpentyl)-dithiophosphinic acid (Cyanex trademark 301) in combination with the synergist tributylphosphate (TBP) could selectively extract trivalent actinides (represented by 241Am) from lanthanides (represented by 152Eu). This study was based on the premise that actinides form more stable complexes with ligands containing soft donor atoms than lanthanides due to a slightly greater covalent bonding component for the actinide ions. However, due to the difference in the radii of Am(III) (1.07 Angstrom) and Eu(III) (0.95 Angstrom), it was necessary to extend the study to include a wider variety of lanthanides to show that the ion radius size was not an important factor in these extractions. In this study the most promising of the three dithiophosphinic acids, HDCHDTP, was used along with the synergist TBP to selectively extract 241Am-from 152Eu, 141Ce, and 88Y (acting as a pseudolanthanide). Large separation factors (up to 540 to 980 depending on the Ln) between the extraction of the actinides over the lanthanides were still observed proving that ionic radius was not the important factor in these extractions

  2. Development of a CMPO based extraction process for partitioning of minor actinides and demonstration with genuine fast reactor fuel solution (155 GWd/Te)

    Antony, M.P.; Kumaresan, R.; Suneesh, A.S. [Indira Gandhi Centre for Atomic Research, Kalpakkam (IN). Fuel Chemistry Div.] (and others)

    2011-07-01

    A method has been developed for partitioning of minor actinides from fast reactor (FR) fuel solution by a TRUEX solvent composed of 0.2 M n-octyl(phenyl)-N,N-diisobutylcarbamoyl-methylphosphine oxide (CMPO)-1.2 M tri-n-butylphosphate (TBP) in n-dodecane (n-DD), and subsequently demonstrated with genuine fast reactor dissolver solution (155 GWd/Te) using a novel 16-stage ejector mixer settler in hot cells. Cesium, plutonium and uranium present in the dissolver solution were removed, prior to minor actinide partitioning, by using ammonium molybdophosphate impregnated XAD-7 (AMP-XAD), methylated poly(4-vinylpyridine) (PVP-Me), and macroporous bifunctional phosphinic acid (MPBPA) resins respectively. Extraction of europium(III) and cerium(III) from simulated and real dissolver solution, and their stripping behavior from loaded organic phase was studied in batch method using various citric acid-nitric acid formulations. Based on these results, partitioning of minor actinides from fast reactor dissolver solution was demonstrated in hot cells. The extraction and stripping profiles of {sup 154}Eu, {sup 144}Ce, {sup 106}Ru and {sup 137}Cs, and mass balance of {sup 241}Am(III) achieved in the demonstration run have been reported in this paper. (orig.)

  3. Development of a CMPO based extraction process for partitioning of minor actinides and demonstration with genuine fast reactor fuel solution (155 GWd/Te)

    A method has been developed for partitioning of minor actinides from fast reactor (FR) fuel solution by a TRUEX solvent composed of 0.2 M n-octyl(phenyl)-N,N-diisobutylcarbamoyl-methylphosphine oxide (CMPO)-1.2 M tri-n-butylphosphate (TBP) in n-dodecane (n-DD), and subsequently demonstrated with genuine fast reactor dissolver solution (155 GWd/Te) using a novel 16-stage ejector mixer settler in hot cells. Cesium, plutonium and uranium present in the dissolver solution were removed, prior to minor actinide partitioning, by using ammonium molybdophosphate impregnated XAD-7 (AMP-XAD), methylated poly(4-vinylpyridine) (PVP-Me), and macroporous bifunctional phosphinic acid (MPBPA) resins respectively. Extraction of europium(III) and cerium(III) from simulated and real dissolver solution, and their stripping behavior from loaded organic phase was studied in batch method using various citric acid-nitric acid formulations. Based on these results, partitioning of minor actinides from fast reactor dissolver solution was demonstrated in hot cells. The extraction and stripping profiles of 154Eu, 144Ce, 106Ru and 137Cs, and mass balance of 241Am(III) achieved in the demonstration run have been reported in this paper. (orig.)

  4. Determination of plutonium americium and curium in soil samples by solvent extraction with trioctylphosphine oxide

    A method of Pu, Am and Cm determination in soil samples, which was developed for analyzing samples from territories subjected to radioactive contamination as a result of the Chernobyl accident is described. After preliminary treatment the samples were leached by solution of 7 mol/l HNO23+0.3 mol/l KBrO3 during heating. Pu was isolated by extraction with 0.05 mol TOPO from 7 mol/l HNO3. 144Ce and partially remaining in water phase isotopes of Zr, U and Th were isolated in an extraction-chromatographic column with TOPO and PbO2. Then Am and Cm were extracted by 0.2 mol/l TOPO from solution 1 mol/l HLact+0.07 mol/l DTPA+1 mol/l Al(NO3)3. Alpha-activity of both extracted products was determined in liquid scintillation counter. Chemical yield of plutonium counted to 85±10%, that of americium and curium -75±10%. 17 refs

  5. Study of the behaviour of transuranics and possible chemical homologues in Lake Michigan water and biota

    Concentration factors for Pu, Am and U in Lake Michigan biota are compared to those of a number of stable trace elements that have short residence times in Lake Michigan water. The relative order of uptake for these nuclides in Lake Michigan biota is Am>Pu much>U. Evidence is summarized which suggests that the predominant oxidation state of 239, 240Pu in Lake Michigan water is 4+. Concentrations of 239, 240Pu in net plankton, filterable particulate matter, sediment trap, and benthic floc samples indicate that sorption by biogenic detritus, and settling of this material, can account for the reduced concentration of 239, 240Pu observed in surface waters during summer stratification, but that deposition into the sediments is primarily non-biological. Concentrations of 7Be, 144Ce and 137Cs in sediment trap samples show the effect of spring convective mixing and demonstrate the resuspension of mineral-rich surficial sediments during the summer months. The effect on the concentration of dissolved plutonium in the water column, of varying degrees of resuspension of sedimentary floc, is described using a simple mass-action model. A radiochemical method for the determination of americium and uranium in Lake Michigan environmental samples is also presented. (author)

  6. Calibration of Ge(Li) semiconductor detector by method using agar volume source

    The Ge(Li) semiconductor detector was calibrated for measurements of environmental samples. The radioisotopes used for standard sources are 22Na, 51Cr, 56Co, 57Co, 133Ba, 137Cs, 144Ce and 241Am. These are mixed with hot agar aqueous solution and fixed uniformly in a cylindrical plastic case in cooling. The agar volume source is advantageous in handling over the fluid aqueous source. The prepared cylindrical standard sources are in diameters 6 and 8 cm and thicknesses 1, 5, 10, 20, 30 and 40 mm (only for 8 cm diameter). The radioactivities of prepared standard sources are between 0.03 μCi and 0.2 μCi. It takes only a week to make the calibration except data processing. The obtained full energy peak efficiency curves include 5 - 10% error due to preparation of agar source, reference radioactivity data of purchased standard solutions, reference data of branching ratio of gamma-ray and sum effect. The efficiency curves, however, are sufficient for quantitative analysis of environmental samples. (author)

  7. Varieties of fuel particles in fallout of the Chernobyl NPP exclusion zone

    Soil in the Chernobyl NPP 30-km zone is known to be contaminated by fine particles of dispersed irradiated fuel. Experimental data obtained by the authors shortly after the accident indicated a significant excess of 95Zr in the particles compared with its calculated amount. This suggested that particles of the U fuel also contain construction material from the core, activated Zr. The authors have isolated particles of radioactive material from the heavy soil fraction in order experimentally to confirm this. Their dimensions varied from 85 to 750 μm; their mass, from 10 to 700 μg. Such characteristics as the microstructure, elemental composition, and the concentration of 144Ce and other radionuclides obtained from electron microscope measurements, microprobe analysis, and γ- and α-spectrometry were used to classify the particles. It was found that two types of highly active particles are characteristic of the Chernobyl NPP exclusion zone (up to 4-5 km) and the western track of the fallout for a distance of 20 km from the destroyed fourth block. The first type are genuine particles of irradiated fuel. The second type are aggregates consisting of U and Zr oxides. The second type predominates in fallout of the exclusion zone and in the western track

  8. Animal metabolism

    Studies on placental transport included the following: clearance of tritiated water as a baseline measurement for transport of materials across perfused placentas; transport of organic and inorganic mercury across the perfused placenta of the guinea pig in late gestation; and transport of cadmium across the perfused placenta of the guinea pig in late gestation. Studies on cadmium absorption and metabolism included the following: intestinal absorption and retention of cadmium in neonatal rats; uptake and distribution of an oral dose of cadmium in postweanling male and female, iron-deficient and normal rats; postnatal viability and growth in rat pups after oral cadmium administration during gestation; and the effect of calcium and phosphorus on the absorption and toxicity of cadmium. Studies on gastrointestinal absorption and mineral metabolism included: uptake and distribution of orally administered plutonium complex compounds in male mice; gastrointestinal absorption of 144Ce in the newborn mouse, rat, and pig; and gastrointestinal absorption of 95Nb by rats of different ages. Studies on iodine metabolism included the following: influence of thyroid status and thiocyanate on iodine metabolism in the bovine; effects of simulated fallout radiation on iodine metabolism in dairy cattle; and effects of feeding iodine binding agents on iodine metabolism in the calf

  9. Waste/Rock Interactions Technology Program. Status report on LWR spent-fuel leach tests

    Spent fuels with burnups of 9000, 28,000 and 54,500 MWd/MTU have been leach tested at 250C. Three leach-test procedures (Paige, IAEA and static) were used. IAEA and static tests were conducted in five different solutions: deionized water, sodium bicarbonate, sodium chloride, calcium chloride and Waste Isolation Pilot Plant B brine solutions. Elemental leach data are reported based on the release of 90Sr+90Y, 106Ru, 137Cs, 144Ce, 154Eu, 239+240Pu, 125Sb, 244Cm, 129I, 99Tc, and total uranium. This is the first report on 129I and 99Tc from spent fuel. Termination of the Paige test showed that the plateout (radionuclide adsorption) on the test apparatus had negligible effect on the leach rate of cesium and plutonium, but a major (up to a factor of 50 times) effect on the curium leach rate. Three-hundred additional days of leach testing by the IAEA procedure, from 467 to 769 d, showed a continuation of the leaching trends observed during the first 467 d. Results from the first two static leach test series, 2 and 8 d, gave the 129I and 99Tc release numbers

  10. Communication of nuclear data progress No. 21 (1999)

    The 21th issue of Communication of Nuclear Data Progress (CNDP) is presented, in which the achievements of last half year in nuclear data field in China are carried.It includes the measurement of differential cross sections for 6Li(n,t)4He reaction at 3.67 and 4.42 MeV, 14 MeV neutron activation cross section for 93Nb (n,2n)92Nb reaction, double differential cross sections for 39K(n,α36Cl reaction at 4.41, 5.46, 6.52 MeV; theoretical calculations of n + 235U, 151,153,154,155Eu, 135-138Ba69,71Ga, 83-86Kr at En = 0.001-20 MeV; evaluations of neutron reaction cross sections for 140,141,142,144Ce, 63,65,NatCu, 115In, 105,108Pd and 103Rh, complete data for 63Cu, and photonuclear reaction for 90,91,92,94,96Zr, nuclear data sheets for A = 195 and thermal-neutron captures data evaluation for A = 1-19; construction of covariance matrix for absolute fission yield data measurement; thermal and fast reactor benchmark testing of ENDF/B-6.4. Also the activities on nuclear data in China are summarized

  11. Hazards to the eye lens and gonads from hard beta rays

    Considerable attention has been paid to the protection against x and γ radiation but comparatively less stress has been given to the possible hazard due to external radiation from high-energy beta rays. In order to evaluate the magnitude of this hazard, central-axis depth doses at different source-to-skin distances for 90Sr-90Y and 32P sources were measured. Isodose curves in a testicular phantom for a 90Sr-90Y source were measured. The data of Haybittle for 144Ce for 10 cm SSD has been included. From the measured data, the eye-lens epithelium dose may be as high as 51%, 21.5%, and 82%, respectively, for the three sources instead of 15% as has been conventionally assumed. The isodose curves obtained in the testicular phantom indicate that an appreciable amount of testicular tissue can be subjected to radiation exposures. The radiation hazards due to high-energy beta rays are not negligible and considerable care should be exercised while using these sources

  12. Extrapolation of experimental data on late effects of low-dose radionuclides in man

    The situation of living of population on radionuclide contamination areas was simulated in the experimental study using white strainless rats of different ages. The significance of age for late stochastic effects of internal radionuclide contamination with low doses of 131I, 137Cs, 144Ce and 106Ru was studied. Some common regularities and differences in late effects formation depending on age were found. Results of the study showed that the number of tumors developed increased in groups of animals exposed at the youngest age. The younger animal at the moment of internal radionuclide contamination, the higher percentage of malignant tumors appeared. It was especially so for tumors of endocrine glands (pituitary, suprarenal,- and thyroid). Differences in late effects formation related to different type of radionuclide distribution within the body were estimated. On the base of extrapolation the conclusion was made that human organism being exposed at early postnatal or pubertal period could be the most radiosensitive (1.5-2.0 or sometimes even 3-5 times higher than adults). Data confirmed the opinion that children are the most critical part of population even in case of low dose radiation exposure. (author)

  13. Assay of long-lived radionuclides in low-level wastes from power reactors

    The 10 CFR Part 61 waste classification system includes several nuclides which are difficult to assay without expensive radiochemical methods. In order for waste generators to classify wastes practically, NRC Staff has recommended the use of correlation factors to scale the difficult-to-measure nuclides with nuclides which can be measured more easily (i.e., gamma emitters such as 60Co or 137Cs). In this study, Science Applications International Corporation (SAIC) performed complete radiochemical assays for all the 10 CFR Part 61 waste classification nuclides on over 100 samples. These data, along with almost 800 other samples in the SAIC data base, were used to assess the validity of correlation factors suggested for use in nuclear power plant wastes. Specific generic correlation factors are recommended with other approaches to correlate nuclides for which generic scaling factors are not defensible. The primary nuclide correlations studied were 14C, 55Fe, 59Ni, 63Ni, and 94Nb, with 60Co; 90Sr, 99Tc, 129I, 135Cs, and /sup 239, 240/Pu with 137Cs; 238Pu, /sup 239, 240/Pu, 241Pu, 241Am, 242Cm, and /sup 243, 244/Cm with 144Ce; and 238Pu, 241Pu, 241Am, 242Cm and /sup 243, 244/Cm with /sup 239, 240/Pu

  14. Fraction of energy absorbed from β-emitting particles in the rat lung

    Forty-four male Fischer-344 rats were exposed, nose only, to a relatively insoluble aerosol of 144Ce-labeled fused aluminosilicate particles. Fractional β energy absorption was measured 7 to 9 days after exposure for 28 rats (ages 12 to 25 weeks and body weights of 183 to 337 g); lung burdens were 13 to 82 nCi. An additional group of 16 rats was exposed when 12 weeks old and maintained for 6 months prior to analysis; body weights and lung burdens 6 months after exposure ranged from 276 to 368 g and 16 to 46 nCi, respectively. Lungs were carefully removed, inflated, and frozen by immersion in liquid nitrogen. The energy spectrum from each lung was measured in a 4π β spectrometer, keeping the lung frozen throughout this procedure. Over the range of lung sizes in this study (0.88 to 1.66 g) the mean fractional energy absorption and standard deviation were 0.23 +- 0.078, respectively. Results agreed well with theory, indicating that calculated values for fractional energy absorption in the lung can be used for a range of lung sizes and β energies. Calculated values for fractional energy absorption as a function of β energy are included for several lung sizes between 0.5 and 10 g

  15. A study of the decontamination effect of commercial detergents on the skin

    Titanium dioxide paste is generally used as the radiological skin decontaminant in the radiation control area at Japan Nuclear Cycle Development Institute (JNC) Tokai works. It is a typical and proven skin decontaminant in the nuclear industry, but there is a disadvantage in that it has a short shelf life. Recently, many detergents applicable as skin decontaminants have become available in non-nuclear industries such as cosmetics and sanitation. They are easily acquired and have an advantage in that stimulus to the skin is mild, because these products have been developed for the human body. In this study, the decontamination factor of the commercial detergents for each nuclide was examined using imitation skin. Sheets of raw pig skins were contaminated with a nitric-acid solution containing 144Ce, 137Cs, 106Ru or 60Co, and then washed with various detergents such as a neutral detergent, cleansing cream and orange oil. The nuclide removal rates of some of the commercial detergents examined were nearly equal to that of titanium dioxide, thus proving that they show satisfactory decontamination performance as a skin decontaminant. (author)

  16. TMI-2 Reactor Building source term measurements: surfaces and basement water and sediment

    Presented in this report are the results of radiochemical and elemental analyses performed on samples collected from the Three Mile Island Unit 2 Reactor Building from August 1979 to December 1983. The quantities of fission products and core materials that were measured on the external surfaces in the Reactor Building or in the water and sediment in its basement are summarized. Recent analysis results for access panels removed from the air cooling assembly and for liquid and particulate samples collected from the Reactor Building sump and reactor coolant drain tank are included in the report. Measurements show that 59% of the 3H, 2.7% of the 90Sr, 15% of the 129I, 20% of the 131I, and 42% of the 137Cs originally in the core at the time of the accident could be accounted for outside the core in the Reactor Building. With the exceptions of 90Sr and 144Ce, the vast majority of each radionuclide released was found dispersed in the water and sediment in the basement

  17. Studies of environmental radioactivity in Cumbria

    Five stations collecting samples of atmospheric deposition were set up in north Cumbria along a line running inland from the coast for about 17 km. Sampling was continuous from September 1980 to September 1981. Monthly samples were analysed for 106Ru, 137Cs, 144Ce, 238Pu, sup(239,240)Pu, 241Am, 7Be and stable Na, Cl and Al. The objective of the work was to measure the deposition of radionuclides as a function of distance from the sea. By estimating the contributions to the deposition of nuclear weapon test material and of the atmospheric discharges from the British Nuclear Fuels plc works at Sellafield, the effects of the transfer to air and land of radionuclides in the sea could be established. The marine radionuclides were due to the discharges to sea from the Sellafield works. The measurements showed that the deposition was largely due to the sea-to-land transfer process. The highest depositions observed were at 20 m from high water mark, the annual values (rounded, in Bq m-2) being 106Ru, 500; 137Cs, 650; plutonium, 70; 241Am, 30. The highest concentrations in rainwater for the radionuclides studied were less than 3 per cent of the fresh water limits (drinking only) GDL values. The highest estimated accumulations in soil due to atmospheric deposition were less than 1 per cent of the limits. (author)

  18. The long-term behaviour of cemented research reactor waste under the geological disposal conditions of the Boom Clay Formation: results from leach experiments

    The Belgian Nuclear Research Centre SCK-CEN has carried out a number of studies to evaluate the long-term behaviour of cemented research reactor waste under the geological disposal conditions of the Boom Clay Formation. Static leach experiments in synthetic clay water were performed on active samples of cemented research reactor waste. The leach experiments were carried out under anaerobic conditions at two testing temperatures (23 and 85oC). Leach rates of seven radionuclides (60Co, 90Sr, 134Cs, 137Cs, 144Ce, 154Eu and 241Am) were measured. Most investigated radionuclides are well retained within the cement matrix over a 280 days testing period. Results on the source term of radionuclides were complemented with data on the leaching behaviour of cement matrix constituents as Ca, Si, Al, Na, K, Mg and SO4 as well as with data from performance assessment calculations and in situ tests. Despite limitations inherent to short-term experiments, combined results from these investigations indicate only limited interactions of disposed research reactor waste with the near field of a geological repository in clay. (author)

  19. Reconstruction of radionuclide releases from the Hanford Site, 1944-1972

    Historic releases of key radionuclides were estimated as a first step in determining the radiation doses that results from Hanford Site operations. The Hanford Site was built in southcentral Washington State during World War II to provide plutonium for the U.S. nuclear weapons program. As part of the Hanford Environmental Dose Reconstruction (HERD) Project, releases to the Columbia River of 24Na, 32P, 46Sc, 51Cr, 56Mn, 65Zn, 72Ga, 76As, 90Y, 131I, 239Np, and nonvolatile gross beta activity from operation of eight Hanford single-pass production reactors were estimated. Releases of 90Sr, 103Ru, 106Ru, 131I, 144Ce, and 239Pu to the atmosphere from operation of chemical separation facilities were also estimated. These radionuclides and the atmospheric and Columbia River pathways were selected for study because scoping studies showed them to be the largest contributors to dose from Hanford operations. The highest doses resulted from releases to the atmosphere of 131I from chemical separations plants in the pre-1950 period. Prior to 1950, the technology for limiting iodine releases had not been developed. Hence, a very detailed reconstruction of the hourly 131I release history was achieved for 1944-1949 using Monte Carlo methods. Atmospheric releases of the other radionuclides were estimated on a monthly basis for 1944-1972 using deterministic calculations. Monthly releases to the Columbia River for 1944-1971 were based on Monte Carlo methods

  20. Metaphase chromosome aberrations as markers of radiation exposure and dose

    Chromosome aberration frequency provides the most reliable biological marker of dose for detecting acute accidental radiation exposure. Significant radiation-induced changes in the frequency of chromosome aberrations can be detected at very low doses. Our paper provides information on using molecular chromosome probes ''paints'' to score chromosome damage and illustrates how technical advances make it possible to understand mechanisms involved during formation of chromosome aberrations. In animal studies chromosome aberrations provide a method to relate cellular damage to cellular dose. Using an In vivo/In vitro approach aberrations provided a biological marker of dose from radon progeny exposure which was used to convert WLM to dose in rat tracheal epithelial cells. Injection of Chinese hamsters with 144Ce which produced a low dose rate exposure of bone marrow to either low-LET radiation increased the sensitivity of the cells to subsequent external exposure to 60Co. These studies demonstrated the usefulness of chromosome damage as a biological marker of dose and cellular responsiveness

  1. Studies on treatment of radioactive animal carcass, (2)

    A method of dehydration for the waste treatment of radioactive animal carcass by microwave heating was developed. A heating apparatus was devised by annexing the microwave output controlling circuit to a 600 W commercial microwave oven, and the aqueous vapour from the animal carcass was collected by duplex cold traps. Body weight of the carcass was reduced to 20-30% by dehydration, and a three-year storage test proved that the dehydrated carcass was very hard to decompose. Time needed for dehydration was about 10 min for a 25 g mouse, and about 1 hr for 668 g dog. Violent rupture of the carcass, and/or fuming due to overheating that had often been observed during dehydration were proved to be avoidable by controlling the microwave output during the process. The ratio of radioactivity (60Co, 137Cs, 85Sr, 144Ce) that escaped from the carcass during dehydration was found to be less than 3 x 10-4 by a series of experiment. Some related radiation safety problems were discussed. (author)

  2. Tumorigenic responses from single or repeated inhalation exposures to relatively insoluble aerosols of Ce-144

    Human occupational or environmental inhalation exposures may involve repeated or chronic exposures, but most laboratory studies of inhaled radionuclides have involved single exposures. This study was designed to compare the biological effects of repeated inhalation exposures of dogs to a relatively insoluble form of 144Ce with existing data for singly-exposed dogs that had the same cumulative dose to the lungs two years after exposure. To date, the biological effects observed in these repeatedly-exposed dogs have been substantially different from those seen in singly-exposed dogs, particularly during the first 5 years after the initial exposure. Although pulmonary hemangiosarcoma was the prominent biological effect seen in singly-exposed dogs between 2 and 4 years after exposure, no lung tumors were seen during the 5 years after the first of the repeated exposures. This response plus other clinical observations are discussed in relation to the patterns of dose rate and cumulative dose for the different exposure conditions. (H.K.)

  3. Assessment of a Compton-event suppression γ-spectrometer for the detection of fission products at trace levels

    The improvement in detection limits for low and high activity samples measured with the Compton-suppression γ-spectrometer installed at the Institute for Transuranium Elements (ITU) for environmental monitoring of radioactivity, as well as nuclear safeguards, is discussed. The advantage of using two parallel acquisition lines for simultaneous measurement with and without Compton-event suppression is outlined with respect to cascade and non-cascade γ-emitters. The background reduction by Compton-event suppression made it possible to detect small peaks, which otherwise would not have been found in a conventional spectrum. In Compton-event suppression mode, the detection limit for 137Cs was improved by a factor of about 3, for 241Am we found a factor of 1.2 both in high and low active samples. The measurements of environmental reference samples showed good agreement with certified values in both acquisition modes. The application of this instrument for the determination of fission products in smear samples is described. In particular, for nuclides like 54Mn, 125Sb and 144Ce, an improvement in the detection limits by a factor of 1.6-2.4 was obtained

  4. Development of removal methods of radioactive ruthenium by using the column packed with cell materials

    Ruthenium is an element of various valencies and present in many chemical species of nitro-nitrosyl complexes in nitric acid or in solutions containing nitrates. Since radioactive ruthenium (103Ru, 106Ru) of those chamical species is contained in the wastes occurred on the fuel reprocessing by Purex method and others, it is one of the nuclides which are most difficult to be removed by the conventional methods of the radioactive waste treatments. It was found that this nuclide was effectively removed by passing the waste solution through a column packed with the mixture of powder of anode and cathode materials and depolarizers used in the electric cells. The typical mixtures were zinc-charcoal, zinc.palladium-charcoal, zinc-manganese dioxide.charcoal and zinc-carbon fluoride.charcoal. These column methods showed a surpassing removel efficiency for 106Ru complexes and fisson products. The decontamination factors of radioactive ruthenium were 104 for all kinds of ruthenium complexes and 102 for the species not easily removed by the conventional methods. It was also found that the concentrations of 239Pu, U, 144ce, 155Eu, and 125Sb in the waste could be decreased to that below the limits of detection by the cell material columns. Because 106Ru of chemical species which was difficult to be removed by conventional methods could be efficiently separated from the waste solutions, it was concluded that the columns packed with cell materials are valuable tools in the radioactive waste treatments. (author)

  5. Radionuclide migration experiments in a natural fracture in a quarried block of granite

    A radionuclide migration experiment was performed over a distance of 1 m in a natural fracture in a quarried block of granite. The fracture in the block was characterized hydraulically by measuring the pressure drop in borehole-to-borehole pump tests. The effective fracture volume in the block was ∼100 mL. A silicone coating was applied to the exterior, and the block was immersed in a tank of water to which hydrazine was added to provide a chemically reducing barrier. Migration experiments were performed at a flow rate of 2.2 mL h-1 using 85Sr, 131I,137Cs, 144Ce, 152Eu, 237Np and 238Pu. A total of 9.5 L of groundwater was pumped through the fracture, corresponding to ∼95 fracture volumes. Only 85Sr, 131I, 137Cs, 237Np and 238Pu were observed in the eluent. Scanning of the fracture surface at the end of the migration experiment showed limited mobility of α-emitting radionuclides and of the rare-earth elements, consistent with static sorption data obtained on representative fracture surface material. The mobility of 137Cs was higher than that of the rare-earth elements, but it was lower than that of 85Sr. When samples of fracture-coating material were separated into fractions with different specific gravity, there was a clear indication of radionuclide association with mineral groups. (author)

  6. Radionuclide migration experiments in a natural fracture in a quarried block of granite

    Vandergraaf, Tjalle T.; Drew, Douglas J.; Masuda, Sumio

    1996-02-01

    A radionuclide migration experiment was performed over a distance of 1 m in a natural fracture in a quarried block of granite. The fracture in the block was characterized hydraulically by measuring the pressure drop in borehole-to-borehole pump tests. The effective fracture volume in the block was ˜ 100 mL. A silicone coating was applied to the exterior, and the block was immersed in a tank of water to which hydrazine was added to provide a chemically reducing barrier. Migration experiments were performed at a flow rate of 2.2 mL h -1 using 85Sr, 131I, 137Cs, 144Ce, 152Eu, 237Np and 238Pu. A total of 9.5 L of groundwater was pumped through the fracture, corresponding to ˜95 fracture volumes. Only 85Sr, 131I, 137Cs, 237Np and 238Pu were observed in the eluent. Scanning of the fracture surface at the end of the migration experiment showed limited mobility of α-emitting radionuclides and of the rare-earth elements, consistent with static sorption data obtained on representative fracture surface material. The mobility of 137Cs was higher than that of the rare-earth elements, but it was lower than that of 85Sr. When samples of fracture-coating material were separated into fractions with different specific gravity, there was a clear indication of radionuclide association with mineral groups.

  7. Marine plankton as an indicator of low-level radionuclide contamination in the Southern Ocean

    We have initiated an investigation of the utility of marine plankton as bioconcentrating samplers of low-level marine radioactivity in the southern hemisphere. A literature review shows that both freshwater and marine plankton have trace element and radionuclide concentration factors (relative to water) of up to 104. In the years 1956-1958, considerable work was done on the accumulation and distribution of a variety of fission and activation products produced by the nuclear tests in the Marshall Islands. Since then, studies have largely been confined to a few selected radionuclides, and by far most of this work has been done in the northern hemisphere. We participated in Operation Deepfreeze 1981, collecting 32 plankton samples from the U.S. Coast Guard Cutter Glacier on its Antarctic cruise, while Battelle Pacific Northwest Laboratories concurrently sampled air, water, rain and fallout. We were able to measure concentrations of the naturally occurring radionuclides 7Be, 40K and the U and th series, and we believe that we have detected low levels of 144Ce and 95Nb in seven samples ranging as far south as 680. There is a definite association between the radionuclide content of plankton and air filters, suggesting that aerosol resuspension of marine radioactivity may be occurring. Biological identification of the plankton suggests a possible correlation between radionuclide concentration and foraminifera content of the samples. 38 references, 7 figures, 3 tables

  8. Burn-up determination of irradiated uranium oxide by means of direct gama spectrometry and by radiochemical method

    The burn-up of thermal neutrons irradiated U3O8 (natural uranium) samples has been determined by using both direct gamma spectrometry and radiochemical methods and the results obtained were compared. The fission products 144Ce, 103Ru, 106Ru, 137Cs and 95Zr were chosen as burn-up monitors. In order to isolate the radioisotopes chosen as monitors, a radiochemical separation procedure has been established, in which the solvent extraction technique was used to separate cerium, cesium and ruthenium one from the other and all of them from uranium. The separation between zirconium and niobium and of both elements from the other radioisotopes and uranium was accomplished by means of adsorption on a silica-gel column, followed by selective elution of zirconium and of niobium. When use was made of the direct gamma-ray spectrometry method, the radioactivity of each nuclide of interest was measured in presence of all others. For this purpose use was made of gamma-ray spectrometry and of a Ge-Li detector. Comparison of burn-up values obtained by both methods was made by means of Student's 't' test, and this showed that results obtained in each case are statistically equal. (Author)

  9. Probing new physics with underground accelerators and radioactive sources

    New light, weakly coupled particles can be efficiently produced at existing and future high-intensity accelerators and radioactive sources in deep underground laboratories. Once produced, these particles can scatter or decay in large neutrino detectors (e.g. Super-K and Borexino) housed in the same facilities. We discuss the production of weakly coupled scalars ϕ via nuclear de-excitation of an excited element into the ground state in two viable concrete reactions: the decay of the 0+ excited state of 16O populated via a (p,α) reaction on fluorine and from radioactive 144Ce decay where the scalar is produced in the de-excitation of 144Nd⁎, which occurs along the decay chain. Subsequent scattering on electrons, e(ϕ,γ)e, yields a mono-energetic signal that is observable in neutrino detectors. We show that this proposed experimental setup can cover new territory for masses 250 keV≤mϕ≤2me and couplings to protons and electrons, 10−11≤gegp≤10−7. This parameter space is motivated by explanations of the “proton charge radius puzzle”, thus this strategy adds a viable new physics component to the neutrino and nuclear astrophysics programs at underground facilities

  10. An interspecies comparison of the biological effects of an inhaled, relatively insoluble beta emitter

    Mice, rats, Syrian hamsters, and beagle dogs were exposed by inhalation to graded levels of 144Ce in relatively insoluble forms to demonstrate species similarities and differences regarding patterns of deposition, fate, dosimetry, and dose-response relationships. All animals were serially evaluated to determine lung burdens, held for life-span observation, necropsied at death, and examined histopathologically to characterize the lesions present and to determine the cause of death. The primary malignant lung tumors observed in rodents were predominantly squamous-cell carcinomas and adenocarcinomas, whereas those in dogs at earlier times were primarily hemangiosarcomas and those in dogs that died at later times were pulmonary carcinomas. The relationship between the incidence of lung cancer and absorbed beta dose to the lung differed among species. The results of modeling these data provide a better understanding of how the choice of species can influence the outcome of a life-span study. The data are used to estimate the risk of lung cancer in man from an inhaled beta-emitting radionuclide. 26 refs., 5 figs., 6 tabs

  11. Position of sediments in transfer of radionuclides released into coastal sea to human beings

    A great portion of radionuclides released into coastal sea is adsorbed into marine sediments and the adsorbed radionuclides causes the radioactive contamination of marine organisms and then transferred to human beings who consume them. In order to make a quantitative evaluation of this route, the transfer of 9 kinds of radionuclides from sediments to benthic organisms such as algae, bivalve and worm was observed. Then it was compared with the radioactivity in these organisms from radioactively contaminated sea water (Concentration factor). It was observed that the influence of sea water was larger than that of sediments as it was 104 times larger for 54Mn, 103 times larger for 59Fe, 60Co, 95Zr-95Nb, 106Ru-106Rh and 144Ce-144Pr, 102 times larger for 65Zn and 10-102 times larger for 115mCd and 137Cs. Consequently, sea water can be considered as the main route and sediments as the secondary in the case of quantitative comparison of the effect on the accumulation of radionuclides by marine organisms and in the transfer of radionuclides to human beings

  12. Some analytical aspects of the technologies using molten fluorides

    Analytical activities accompanying the development or a molten fluoride reactor can be divided into 3 groups: (i) Balance analyses of fissile and fertile isotopes and their isotope composition; (ii) Analytical control of the reactor process; and (iii) Special analyses and measurements for physical reactor parameters determination. The first group is formed by the precise determination of U, Pu, Th content and isotope composition. Both destructive and non-destructive methods are recommended. The suitable methods are the following: chemical methods (e.g. titrimetric methods), x-ray fluorescence and IDA with alpha- or mass-spectrometric ending. The mass-spectrometry, ICP-MS and gamma-spectrometry are preferred for the isotope analysis. The analyses important for operating reactor form the second group. There is the determination of important activation and fission products as: 233Pa, 137Cs, 90Sr, 144Ce, rare earth elements, transuranium elements, tritium etc. The methods commonly used are based on gamma-spectrometry, alpha-spectrometry, ICP-MS and LSC. In the last group the analyses used for the determination of reactor parameters or the chemical form of some elements in the melt of fluorides can be included. As an example the mass-spectrometric determination of the capture-to-fission ratio or the use of FTIR spectrometry for the determination of the chemical form of fluoride melt. The paper describes the results of measurements obtained for the systems similar to fluoride melts. The possibility of the methods application is discussed. (author)

  13. Long-lived radionuclides in low-level waste

    In July 1982, the Low-Level Waste Licensing Branch of the NRC, anticipating the impact of the proposed Part 61 to 10 CFR, funded a two-year project by SAI to study the radionuclide contents of LWR generated in low-level waste. The objectives of the study are: (1) to analyze, using verified techniques, 150 archived samples for specified beta- and x-ray-emitting nuclides that had not previously been analyzed; (2) to analyze twenty new samples obtained from operating plants for all relevant nuclides and compare them to previous data to ascertain trends; (3) to develop empirical scaling factors through the use of which concentrations of hard-to-analyze nuclides can be estimated from analyses of the gamma-ray emitting nuclides. The new samples are analyzed and the results are summarized and interpreted. Over fifty archived samples have also been analyzed. We discuss scaling factor development. Factors are presented that relate 63Ni and 59Ni to 60Co for PWRs and to 58Co for BWRs, 90Sr to 137Cs for BWRs and 241Pu, 239Pu, 241Am, and 244Cm to 144Ce for all LWRs. 8 figures, 3 tables

  14. Amchitka Radiobiological Program. Final report, July 1970-December 1979

    The Amchitka Radiobiological Program, to collect biological and environmental samples for radiological analyses, began in 1970 and continued through 1979. The principal objective was to determine the extent of radionuclide contamination from worldwide atmospheric fallout and from the detonation of three underground nuclear tests on Amchitka. Leakage of radionuclides from the underground test sites would be suspected if the amount of contamination was significantly greater than could be attributed to worldwide fallout or if an unexpected assemblage of radionuclides was detected. No radionuclides from the underground sites were detected, except for tritium from the Long Shot test (1965) which produced increased tritium concentrations in surface water and freshwater plants near the test site. This final report compiles all previous data into one report and considers the temporal trends in these data. Two naturally occurring radionuclides, 40K and 7Be, were the most abundantly occurring radionuclides in most samples; in lichen samples either 137Cs or 144Ce had the highest activity. All samples were below applicable Radiation Protection Guides and by 1979 most samples were near or below the statistical detection limits. Increased concentrations of short-lived fallout radionuclides following the Chinese atmospheric tests were found in freshwater and seawater samples and in most indicator organisms

  15. Amchitka Radiobiological Program. Final report, July 1970-December 1979

    Sibley, T.H.; Tornberg, L.D.

    1982-11-01

    The Amchitka Radiobiological Program, to collect biological and environmental samples for radiological analyses, began in 1970 and continued through 1979. The principal objective was to determine the extent of radionuclide contamination from worldwide atmospheric fallout and from the detonation of three underground nuclear tests on Amchitka. Leakage of radionuclides from the underground test sites would be suspected if the amount of contamination was significantly greater than could be attributed to worldwide fallout or if an unexpected assemblage of radionuclides was detected. No radionuclides from the underground sites were detected, except for tritium from the Long Shot test (1965) which produced increased tritium concentrations in surface water and freshwater plants near the test site. This final report compiles all previous data into one report and considers the temporal trends in these data. Two naturally occurring radionuclides, /sup 40/K and /sup 7/Be, were the most abundantly occurring radionuclides in most samples; in lichen samples either /sup 137/Cs or /sup 144/Ce had the highest activity. All samples were below applicable Radiation Protection Guides and by 1979 most samples were near or below the statistical detection limits. Increased concentrations of short-lived fallout radionuclides following the Chinese atmospheric tests were found in freshwater and seawater samples and in most indicator organisms.

  16. Three-dimensional plume dynamics in the vadose zone: PORFLO-3 modeling of a defense waste leak at Hanford

    In 1973, approximately 450 m3 of liquid containing radioactive and chemical wastes leaked from the 241-T-106 single-shell tank into the vadose zone at the US Department of Energy's Hanford Site in south-central Washington State. The extent of the 137Cs, 144Ce, and 106Ru contaminant plumes in the vadose zone was estimated in 1973 and 1978 by gamma spectrometry in monitoring wells. Using site data and the PORFLO-3 computer model, a three-dimensional, transient plume migration model was developed for 106Ru and 137Cs. The model was calibrated to the 1973 measured plumes of 106Ru and 137Cs. The calibrated model was then used to study plume migration up to 1990. The simulated 106Ru distribution for 1978 extended deeper than reported values. The simulated distribution of 137Cs for 1978 approximated the measured distribution; the 1973 and 1978 137Cs distributions are similar because of the long half-life and high sorption coefficient of 137Cs. 8 figs., 15 refs

  17. Measurement of radionuclides in bricks made from refuse ash of sewage sludge

    Since people spend about 80% of their time in buildings, in order to estimate the radiation exposure dose of nation, it is necessary to grasp indoor dose level. It has been known that as for indoor radiation exposure dose, it is different according to the types of buildings, and generally it is low in wooden houses, and high in concrete and brick buildings. This difference is due to the shielding of environmental radiation by building material and the radiation emitted from building materials themselves. In this study, the radionuclides in the bricks made of sewage slude-incinerated ash and red bricks for the reference were investigated. The radiation emitted from the bricks was measured with a thermoluminescence dosimeter (TLD). The sampling and pretreatment, the measuring method, the measurement of the radiation dose on the bricks, and the results are reported. As for the natural radionuclides in the bricks, 7Be was detected in most sludge bricks, and the concentration varied largely according to the data of sampling. It was not detected in red bricks. 40K, 214Bi and 228Ac were detected in all the sludge and red bricks. Artificial radionuclides such as 54Mn, 60Co, 106Ru, 131I, 134Cs and 144Ce were not detected in all the sludge and red bricks. The radiation dose on the sludge and red bricks was 20.5 - 21.7 mR, and constant regardless of the data of sampling. (K.I.)

  18. Application of radiochemical-and direct gamma ray spectrometry methods for the determination of the burnup of irradiated uranium oxide

    The burn-up of U3O8 (natural uranium) samples was determined by using both destructive and non-destructive methods, and comparing the results obtained. The radioisotopes 144Ce, 103Ru, 106Ru, 137Cs and 95Zr were chosen as monitors. In order to isolate the radioisotopes chosen as monitors, a separation scheme has been established in which the solvent extraction technic is used to separate cerium, cesium, and ruthenium one from the other and from uranium. The separation between zirconium and niobium and of both from the others was accomplished by means of adsorption on a silica-gel column. When the non-destructive method was used, the radioactivity of each nuclide of interest was measured in the presence of all others. For this purpose, use was made of gamma-ray spectrometry and a Ge-Li detector. The comparison of burn-up values obtained by both destructive and non-destructive methods was made by means of Student's 't' test, and it has shown that the averages of results obtained in each case are equal. (Author)

  19. The passage of lanthanides (Cd-144, Nd-147, Sm-153, Eu-155 and Tb-160) into fetus and newborn after intravenous contamination of rats and estimation of absorbed dose in whole body and gastrointestinal tract

    The purpose of the study was the determination of the passage of certain lanthanum elements (147Nd, 153Sm, 155Eu and 160Tb) from maternal blood through the placenta to the fetus in the second and third weeks of pregnancy and also estimation of absorbed dose in gastrointestinal tract in newborn rats contaminated with 147Nd, 153Sm, 155Eu and 160Tb. The study demonstrated that the lanthanum elements passed across the placental barrier. Placental retention was several times higher in late pregnancy (in the case of 160Tb it was even 16 - fold greater). In the last period of pregnancy this passage increased with increasing mass number of the elements (Nd160Tb (17%) and decreased with the drop of molecular weight of radionuclides. For all lanthanides tested, the dose of γ-radiation absorbed by newborns could be neglected since it comprised only 0.5% of β-radiation. The absorbed dose of β-radiation during the first week of life of new newborns fed by mother injected with 37 kBq of radionuclides ranged from 204 mGy for 160Tb to 0.23 mGy for 144Ce. (author). 15 refs., 5 figs., 4 tabs

  20. Chernobyl radionuclides in a Black Sea sediment trap.

    Buesseler, K O; Livingston, H D; Honjo, S; Hay, B J; Manganini, S J; Degens, E; Ittekkot, V; Izdar, E; Konuk, T

    The Chernobyl nuclear power station accident released large quantities of vaporized radionuclides, and, to a lesser extent, mechanically released small (less than 1-10 micron) aerosol particles. The total release of radioactivity is estimated to be out of the order of 1-2 x 10(18) Bq (3-5 x 10(7) Ci) not allowing for releases of the xenon and krypton gases. The 137Cs releases of 3.8 x 10(16) Bq from Chernobyl can be compared to 1.3 x 10(18) Bq 137Cs released due to atmospheric nuclear weapons testing. Chernobyl-derived radionuclides can be used as transient tracers to study physical and biogeochemical processes. Initial measurements of fallout Chernobyl radionuclides from a time-series sediment trap at 1,071 m during June-September 1986 in the southern Black Sea are presented. The specific activities of 137Cs, 144Ce and 106Ru in the trap samples (0.5-2, 4-12 and 6-13 Bq g-1) are independent of the particle flux while their relative activities reflect their rates of scavenging in the order Ce greater than Ru greater than Cs. PMID:3670387

  1. A probable radiation-induced epidermal carcinoma in a sheep

    The sheep discussed in this report was one of 12 wether lambs given daily doses of 144Ce-144Pr to investigate the effect of radionuclides on the alimentary tract. The sheep received 20 mCi daily over a 16 day period when treatment was discontinued due to the development of sever diarrhea and later anorexia. Changes in the sheep reported (alopecia, ulceration, disappearance of adnexa, and fibrous replacement of the dermal collagen) indicate a radiation dose in excess of that used in previous experiments. About 4.5 yr after dosing, a firm enlargement was noticed in the right ventrolateral coccygeal region. As the enlargement increased in size, ulceration and bacterial infection occurred. The sheep was killed 59 months after initial treatment and a necropsy performed. The findings were consistent with the diagnosis of locally invasive squamouscell carcinoma. The authors feel that the relative rarity of epidermal carcinomas in sheep, exposure of the coccygeal area to large doses of irradiation, and the carcinogenic effect of radiation indicates a probable cause-and-effect relationship of radiation and tumour development. (U.K.)

  2. Release behavior of metallic fission products from pyrocarbon-coated uranium-dioxide particles at extremely high temperatures

    Hayashi, Kimio; Fukuda, Kousaku (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment)

    1990-04-01

    Uranium-dioxide particles coated by pyrocarbon (BISO), which were irradiated at 1,300 {approx} 1,400degC to burnups of ca. 1% FIMA, were heated isochronally and isothermally at temperatures between 1,600 and 2,300degC. Release fractions of {sup 137}Cs, {sup 155}Eu and {sup 106}Ru were larger than 10{sup -2} after heating at 2,000degC for 2 h; the results were in contrast to much smaller release fractions from TRISO particles with intact silicon-carbide (SiC) coating. The release of {sup 137}Cs and {sup 144}Ce from the BISO particle was controlled by diffusion in the dense pyrocarbon layer at temperatures between 1,600 and 2,300degC, while that of {sup 155}Eu and {sup 106}Ru was controlled by diffusion in the fuel kernel above 1,800degC. These results can be used as reference data on release behavior of the fission products from TRISO particles with defective SiC layers. (author).

  3. Release behavior of metallic fission products from pyrocarbon-coated uranium-dioxide particles at extremely high temperatures

    Uranium-dioxide particles coated by pyrocarbon (BISO), which were irradiated at 1,300 ∼ 1,400degC to burnups of ca. 1% FIMA, were heated isochronally and isothermally at temperatures between 1,600 and 2,300degC. Release fractions of 137Cs, 155Eu and 106Ru were larger than 10-2 after heating at 2,000degC for 2 h; the results were in contrast to much smaller release fractions from TRISO particles with intact silicon-carbide (SiC) coating. The release of 137Cs and 144Ce from the BISO particle was controlled by diffusion in the dense pyrocarbon layer at temperatures between 1,600 and 2,300degC, while that of 155Eu and 106Ru was controlled by diffusion in the fuel kernel above 1,800degC. These results can be used as reference data on release behavior of the fission products from TRISO particles with defective SiC layers. (author)

  4. Interaction of radionuclides with geomedia associated with the Waste Isolation Pilot Plant (WIPP) site in New Mexico

    A survey of the potential of geological media from the vicinity of the Waste Isolation Pilot Plant site in Southeastern New Mexico for retardation of radionuclide migration in an aqueous carrier was conducted. The survey included the measurement of sorption coefficients (Kd) for twelve radionuclides between three natural water simulants and ten samples from various geological strata. The nuclides included 137Cs, 85Sr, 131I, 99Tc, 125Sb, 144Ce, 152Eu, 153Gd, 106Ru, 243Am, 244Cm, and 238Pu. The compositions of the simulant solutions were those expected of water in contact with potash minerals or halite deposits in the area and in a typical groundwater found in the Delaware Basin. The geological samples were obtained from potential aquifers above and below the proposed repository horizons and from bedded salt deposits in the repository horizons. In brine solutions, Tc and I were not significantly adsorbed by any of the minerals and Cs and Sr showed minimal adsorption (Kd's 103 and Ru and Sb Kd's varied in the range of 25 to > 103. In the groundwater simulant, Tc and I showed the same behavior, but the Kd's of the other nuclides were generally higher. Some initial parametric studies involving pH, trace organic constituents in the simulant solutions, and radionuclide concentrations were carried out. Significant differences in the observed Kd's can result from varying one or more of these solution parameters

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

    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

  6. Innovative separation method for advanced spent fuel reprocessing based on tertiary pyridine resin

    Radiochemical separation experiments have been performed in order to realize a novel reprocessing method based on chromatography techniques using a novel pyridine resin. The newly synthesized tertiary pyridine resin with two functions of ion exchanger and soft-donor was dedicated to the experiments, where highly irradiated mixed oxide fuel from the experimental fast reactor JOYO was used as a reference spent fuel. With a 3-step separation, pure Am and Cm were individually obtained as minor actinide products, and 106Ru group, lanthanides with 137Cs group and Pu group were fractionated, respectively. The decontamination factor of 137Cs and trivalent lanthanides (155Eu, 144Ce) against the Am product exceeded 3.9 x 104 and 1.0 x 105, respectively. The decontamination factor as the mutual separation of 243Cm was larger than 2.2 x 103 against the Am product. Moreover, the content of 137Cs, trivalent lanthanides and 243Cm in Am product did not exceed 2 ppm. The tertiary pyridine resin method is a candidate separation system for an 'advanced ORIENT process', where enhanced separation, transmutation and utilization of actinides, long-lived fission products and rare metal fission product would be oriented. (author)

  7. Chemical and physical considerations of the use of nuclear fuel spikants for deterrence

    Selle, J. E.

    1978-10-01

    One proposed method of inhibiting the diversion of nuclear fuel for clandestine purposes is to add to the fuel a highly gamma-active material of such intensity that remote handling equipment is necessary in all stages of handling and reprocessing. This is called spiking for deterrence. The present work sought to identify candidate spikants and identify potential materials problems that might occur as the result of incorporation of these spikants with the fuel. Potential spikants were identified and thermodynamic analysis was performed to determine their chemical and physical states. Phase relationships between spikants (and their decay products) and the fuel constituents were surveyed. According to criteria defined in this report, /sup 60/Co, /sup 106/Ru, and /sup 144/Ce appear to have the greatest potential as spikants. Cerium should be present as the oxide, soluble in the fuel, while cobalt and ruthenium should be present in the metallic state with very low solubility in the fuel. Experimental work on the distribution of fission products and their interactions with cladding was also surveyed to provide information on the distribution of spikants in the fuel and describe the probable effects of spikants on the fuel. Cobalt, ruthenium, and cerium should not present any problems due to reaction with stainless steel cladding.

  8. Results of gamma-scanning measurements on Windscale AGR stringer Mk4/S46 and implications for civil AGRs

    Axial rating distributions in a WAGR fuel stringer were determined retrospectively using the measured gamma count rates from five fission products after cooling times of 70 to 100 days. The results from all five isotopes were in general agreement with predictions using the Windscale code CAMPARI, but revealed mutually consistent discrepancies with prediction near the top axial reflector. The measurements were conducted to test the gamma-scanning apparatus and methods of analysis in preparation for the post irradiation examination of CAGR fuel. It was concluded from the results that accuracies of +- 2% to +- 3% (1 sigma) should be attainable in the determination of relative ratings using the measured gamma count rates from the isotopes 140Ba, 103Ru, 95Zr, 144Ce and 137Cs. The accuracies will, however, depend on the type of fuel being examined and the fission product used. In particular, care must be taken when using 137Cs since it may migrate from its point of formation, and cooling times of less than 110 days must be achieved to measure relative concentrations of the short-lived isotope 140Ba with sufficient accuracy. (author)

  9. Probing New Physics with Underground Accelerators and Radioactive Sources

    Izaguirre, Eder; Pospelov, Maxim

    2014-01-01

    New light, weakly coupled particles can be efficiently produced at existing and future high-intensity accelerators and radioactive sources in deep underground laboratories. Once produced, these particles can scatter or decay in large neutrino detectors (e.g Super-K and Borexino) housed in the same facilities. We discuss the production of weakly coupled scalars $\\phi$ via nuclear de-excitation of an excited element into the ground state in two viable concrete reactions: the decay of the $0^+$ excited state of $^{16}$O populated via a $(p,\\alpha)$ reaction on fluorine and from radioactive $^{144}$Ce decay where the scalar is produced in the de-excitation of $^{144}$Nd$^*$, which occurs along the decay chain. Subsequent scattering on electrons, $e(\\phi,\\gamma)e$, yields a mono-energetic signal that is observable in neutrino detectors. We show that this proposed experimental set-up can cover new territory for masses $250\\, {\\rm keV}\\leq m_\\phi \\leq 2 m_e$ and couplings to protons and electrons, $10^{-11} < g_e...

  10. Neutron cross sections of 28 fission product nuclides adopted in JENDL-1

    This is the final report concerning the evaluated neutron cross sections of 28 fission product nuclides adopted in the first version of Japanese Evaluated Nuclear Data Library (JENDL-1). These 28 nuclides were selected as being most important for fast reactor calculations, and are 90Sr, 93Zr, 95Mo, 97Mo, 99Tc, 101Ru, 102Ru, 103Rh, 104Ru, 105Pd, 106Ru, 107Pd, 109Ag, 129I, 131Xe, 133Cs, 135Cs, 137Cs, 143Nd, 144Ce, 144Nd, 145Nd, 147Pm, 147Sm, 149Sm, 151Sm, 153Eu and 155Eu. The status of the experimental data was reviewed over the whole energy range. The present evaluation was performed on the basis of the measured data with the aid of theoretical calculations. The optical and statical models were used for evaluation of the smooth cross sections. An improved method was developed in treating the multilevel Breit-Wigner formula for the resonance region. Various physical parameters and the level schemes, adopted in the present work are discussed by comparing with those used in the other evaluations such as ENDF/B-IV, CEA, CNEN-2 and RCN-2. Furthermore, the evaluation method and results are described in detail for each nuclide. The evaluated total, capture and inelastic scattering cross sections are compared with the other evaluated data and some recent measured data. Some problems of the present work are pointed out and ways of their improvement are suggested. (author)