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Sample records for h-451 nuclear grade

  1. Properties of unirradiated fuel element graphites H-451 and SO818. [Bulk density, tensile properties, thermal expansion, thermal conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Engle, G.B.; Johnson, W.R.

    1976-10-08

    Nuclear graphites H-451, lot 440 (Great Lakes Carbon Corporation (GLCC)), and SO818 (Airco Speer Division, Air Reduction Corporation (AS)) are described, and physical, mechanical, and chemical property data are presented for the graphites in the unirradiated state. A summary of the mean values of the property data and of data on TS-1240 and H-451, lot 426, is tabulated. A direct comparison of H-451, lot 426, chosen for Fort St. Vrain (FSV) fuel reload production, TS-1240, and SO818 may be made from the table. (auth)

  2. Diffusion of uranium in H-451 graphite at 900 to 14000C

    International Nuclear Information System (INIS)

    Tallent, O.K.; Wichner, R.P.; Towns, R.L.

    1983-03-01

    In this study, the diffusion of uranium (as a stand-in for plutonium) was investigated under conditions approximating those of the primary coolant loop in a High Temperature Gas-Cooled Reactor (HTGR). Profiles were obtained for uranium penetration in H-451 graphite (from the Great Lakes Carbon Company) at temperatures ranging from 900 to 1400 0 C. Diffusion coefficients are established for UO 2 and UC 2

  3. Preserving Nuclear Grade Knowledge

    Energy Technology Data Exchange (ETDEWEB)

    Lange, Bob

    2008-02-05

    When people think of the government they think of the President, or Congress, or the Internal Revenue Service (IRS), but there are thousands of people in government-related jobs doing things most don’t really notice everyday. You can find them everywhere, from the space science folks at NASA, to the Federal Bureau of Investigations (FBI) watching out for the bad guys. There are Rangers, and Social Workers, Nurses and Agricultural Managers. They are people working to keep the many facets of the USA rolling. One very diverse bunch is The Department of Energy (DOE) , a group who is expanding the ways we make and save energy to power our cars, homes, and businesses. Tucked away under the DOE is the National Nuclear Security Administration, the NNSA is an agency that maintains the safety, security, and reliability of the U.S. nuclear weapons stockpile. It works to reduce global danger from weapons of mass destruction. It provides the U.S. Navy with safe nuclear propulsion, and it responds to nuclear and radiological emergencies in the United States and abroad, and it supports efforts in science and technology*. (* DOE/NNSA/KCP website info)

  4. Obtention of nuclear grade graphite

    International Nuclear Information System (INIS)

    Ferreira, M.L.

    1984-01-01

    The impurity level of natural graphite found in some of the most important mines of the State of Minas Gerais - Brasil is determined. It is also concerned with the development and use of natural graphite in nuclear reactors. Standard methods for chemical and instrumentsal analysis such as Spectrografic Determination by Emission, Spectrografic Determination by X-Rays, Spectrografic Determination by Atomic Asorption, Photometric Determination, and also chemical and physical methods for separation of impurities as well standard method for Estimating the Thermal Neutron Absorption Cross Section of graphite were employed. Some aditionals methods of purification to the ordinary treatment such as the use of metanol and halogens are also described. (Author) [pt

  5. Production of nuclear grade zirconium: A review

    Energy Technology Data Exchange (ETDEWEB)

    Xu, L., E-mail: L.Xu-2@tudelft.nl [School of Materials Science and Metallurgy, Northeastern University, Shenyang 110004 (China); Department of Materials Science and Engineering, Delft University of Technology, Delft 2628 CD (Netherlands); Xiao, Y. [Department of Metallurgical Engineering, Anhui University of Technology, Ma' anshan 243002 (China); Zr-Hf-Ti Metallurgie B.V., Den Haag 2582 SB (Netherlands); Sandwijk, A. van [Zr-Hf-Ti Metallurgie B.V., Den Haag 2582 SB (Netherlands); Xu, Q. [School of Materials Science and Metallurgy, Northeastern University, Shenyang 110004 (China); Yang, Y. [Department of Materials Science and Engineering, Delft University of Technology, Delft 2628 CD (Netherlands)

    2015-11-15

    Zirconium is an ideal material for nuclear reactors due to its low absorption cross-section for thermal neutrons, whereas the typically contained hafnium with strong neutron-absorption is very harmful for zirconium as a fuel cladding material. This paper provides an overview of the processes for nuclear grade zirconium production with emphasis on the methods of Zr–Hf separation. The separation processes are roughly classified into hydro- and pyrometallurgical routes. The known pyrometallurgical Zr–Hf separation methods are discussed based on the following reaction features: redox characteristics, volatility, electrochemical properties and molten salt–metal equilibrium. In the present paper, the available Zr–Hf separation technologies are compared. The advantages and disadvantages as well as future directions of research and development for nuclear grade zirconium production are discussed.

  6. EDF specifications on nuclear grade resins

    International Nuclear Information System (INIS)

    Mascarenhas, Darren; Gressier, Frederic; Taunier, Stephane; Le-Calvar, Marc; Ranchoux, Gilles; Marteau, Herve; Labed, Veronique

    2012-09-01

    Ion exchange resins are widely used across EDF, especially within the nuclear division for the purification of water. Important applications include primary circuit, secondary circuit and effluent treatment, which require high quality nuclear grade resins to retain the dissolved species, some of which may be radioactive. There is a need for more and more efficient purification in order to decrease worker dose during maintenance but also to decrease volumes of radioactive resin waste. Resin performance is subject to several forms of degradation, including physical, chemical, thermal and radioactive, therefore appropriate resin properties have to be selected to reduce such effects. Work has been done with research institutes, manufacturers and on EDF sites to select these properties, create specifications and to continuously improve on these specifications. An interesting example of research regarding resin performance is the resin degradation under irradiation. Resins used in the CVCS circuit of EDF nuclear power plants are subject to irradiation over their lifetime. A study was carried out on the effects of total integrated doses of 0.1, 1 and 10 MGy on typically used EDF mixed bed resins in a 'mini-CVCS' apparatus to simultaneously test actual primary circuit fluid. The tests confirmed that the resins still perform efficiently after a typical CVCS radiation dose. Certain resins also need additional specifications in order to maintain the integrity of the particular circuits they are used in. Recently, EDF has updated its requirements on these high purity nuclear grade resins, produced generic doctrines for all products and materials used on site which include resins of all grades, and as a result have also updated a guide on recommended resin usage for the French fleet of reactors. An overview of the evolutions will be presented. (authors)

  7. The Fracture Toughness of Nuclear Graphites Grades

    Energy Technology Data Exchange (ETDEWEB)

    Burchell, Timothy D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Erdman, III, Donald L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lowden, Rick R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hunter, James A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hannel, Cara C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-04-01

    New measurements of graphite mode I critical stress intensity factor, KIc (commonly referred to as the fracture toughness) and the mode II critical shear stress intensity, KIIc, are reported and compared with prior data for KIc and KIIc. The new data are for graphite grades PCEA, IG-110 and 2114. Variations of KIc and acoustic emission (AE) data with graphite texture are reported and discussed. The Codes and Standards applications of fracture toughness, KIc, data are also discussed. A specified minimum value for nuclear graphite KIc is recommended.

  8. Cost effective nuclear commercial grade dedication

    International Nuclear Information System (INIS)

    Maletz, J.J.; Marston, M.J.

    1991-01-01

    This paper describes a new computerized database method to create/edit/view specification technical data sheets (mini-specifications) for procurement of spare parts for nuclear facility maintenance and to develop information that could support possible future facility life extension efforts. This method may reduce cost when compared with current manual methods. The use of standardized technical data sheets (mini-specifications) for items of the same category improves efficiency. This method can be used for a variety of tasks, including: Nuclear safety-related procurement; Non-safety related procurement; Commercial grade item procurement/dedication; Evaluation of replacement items. This program will assist the nuclear facility in upgrading its procurement activities consistent with the recent NUMARC Procurement Initiative. Proper utilization of the program will assist the user in assuring that the procured items are correct for the applications, provide data to assist in detecting fraudulent materials, minimize human error in withdrawing database information, improve data retrievability, improve traceability, and reduce long-term procurement costs

  9. [Reproducibility of Fuhrman nuclear grade: advantages of a two-grade system].

    Science.gov (United States)

    Letourneux, Hervé; Lindner, Véronique; Lang, Hervé; Massfelder, Thierry; Meyer, Nicolas; Saussine, Christian; Jacqmin, Didier

    2006-06-01

    The Fuhrman nuclear grade is the reference histoprognostic grading system routinely used all over the world for renal cell carcinoma. Studies measuring the inter-observer and intra-observer concordance of Fuhrman grade show poor results in terms of reproducibility and repeatability. These variations are due to a certain degree of subjectivity of the pathologist in application of the definition of tumour grade, particularly nuclear grade. Elements able to account for this subjectivity in renal cell carcinoma are identified from a review of the literature. To improve the reliability of nuclear grade, the territory occupied by the highest grade must be specified and the grades should probably be combined. At the present time, regrouping of grade 1 and 2 tumours as low grade and grade 3 and 4 tumours as high grade would achieve better reproducibility, while preserving the prognostic: value for overall survival. The development of new treatment modalities and their use in adjuvant situations will imply the use of reliable histoprognostic factors to specify, indications.

  10. Quality assurance grading of conventional equipment at nuclear power station

    International Nuclear Information System (INIS)

    Li Ping; Li Shichang

    2006-01-01

    Equipment QA grading with the systematic and standardized approach will benefit the concerned organizations by effective allocating of limited resources to guarantee the quality of essential equipment. This paper presents a new quality assurance grading system for the convention systems/equipment of nuclear power station, which is operative and at the same time could help the owner to allot resource reasonably through the analysis of the purpose of grading and the experience and lessons of LINGAO Phase I project. (authors)

  11. Ignition properties of nuclear grade activated carbons

    International Nuclear Information System (INIS)

    Freeman, W.P.; Hunt, J.R.; Kovach, J.L.

    1983-01-01

    The ignition property of new activated carbons used in air cleaning systems of nuclear facilities has been evaluated in the past, however very little information has been generated on the behavior of aged, weathered carbons which have been exposed to normal nuclear facility environment. Additionally the standard procedure for evaluation of ignition temperature of carbon is performed under very different conditions than those used in the design of nuclear air cleaning systems. Data were generated evaluating the ageing of activated carbons and comparing their CH 3 131 I removal histories to their ignition temperatures. A series of tests were performed on samples from one nuclear power reactor versus use time, a second series evaluated samples from several plants showing the variability of atmospheric effects. The ignition temperatures were evaluated simulating the conditions existing in nuclear air cleaning systems, such as velocity, bed depth, etc., to eliminate potential confusion resulting from artifically set current standard conditions

  12. 77 FR 51581 - Request for a License To Export Nuclear Grade Graphite

    Science.gov (United States)

    2012-08-24

    ... NUCLEAR REGULATORY COMMISSION Request for a License To Export Nuclear Grade Graphite Pursuant to... 27, 2012, graphite for of nuclear grade graphite to the XMAT424, 11006032. nuclear end use. graphite. Shanghai Institute of Applied Physics in China to test various types of nuclear grade graphite material in...

  13. Standard specification for nuclear-grade beryllium oxide powder

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    This specification defines the physical and chemical requirements of nuclear-grade beryllium oxide (BeO) powder to be used in fabricating nuclear components. This specification does not include requirements for health and safety. It recognizes the material as a Class B poison and suggests that producers and users become thoroughly familiar with and comply to applicable federal, state and local regulations and handling guidelines. Special tests and procedures are given

  14. Development of nuclear grade stainless steels at KCSSL

    International Nuclear Information System (INIS)

    Balachandran, G.; Dhere, M.; Mahadik, A.; Hinge, N.M.; Balasubramanian, V.

    2011-01-01

    Kalyani Carpenter Special Steels Ltd is an alloy steel plant, where a variety of alloy steel grades are produced for automotive, defence, nuclear and aerospace applications. The plant has developed expertise in processing of several alloy steel grades of superior quality that meets stringent specifications. Primary steel is processed through a combination of electric arc furnace, ladle furnace and vacuum degassing where stringent control over dephosphorisation, desulphurization, deoxidation is effected to get a refined high quality steel. The molten steel is cast through continuous casting of slabs or ingot casting. In grades specific to nuclear application, the primary cast products are further subjected to electroslag remelting to achieve further freedom from inclusions and to achieve a favourable solidification grain structure, which ultimately improve the hot workability of the alloy steel. Appropriate choice of slag and operating parameters are needed for realising the required ingot quality. The present study would examine the processing and quality aspects of some important grades of steels used in nuclear industry namely ferritic 9Cr-1Mo steel, martensitic stainless steels 403, 410, precipitation hardenable 17-4 PH stainless steel and austenitic 321, 316LN stainless steel, which were made and supplied for applications to Indian nuclear industry. The expertise developed in processing the steels in terms of melting, heat treatment and their relationship to structural features and mechanical properties would be highlighted. (author)

  15. Nondestructive evaluation of nuclear-grade graphite

    Science.gov (United States)

    Kunerth, D. C.; McJunkin, T. R.

    2012-05-01

    The material of choice for the core of the high-temperature gas-cooled reactors being developed by the U.S. Department of Energy's Next Generation Nuclear Plant Program is graphite. Graphite is a composite material whose properties are highly dependent on the base material and manufacturing methods. In addition to the material variations intrinsic to the manufacturing process, graphite will also undergo changes in material properties resulting from radiation damage and possible oxidation within the reactor. Idaho National Laboratory is presently evaluating the viability of conventional nondestructive evaluation techniques to characterize the material variations inherent to manufacturing and in-service degradation. Approaches of interest include x-ray radiography, eddy currents, and ultrasonics.

  16. Nuclear grade and necrosis predict prognosis in malignant epithelioid pleural mesothelioma: a multi-institutional study.

    Science.gov (United States)

    Rosen, Lauren E; Karrison, Theodore; Ananthanarayanan, Vijayalakshmi; Gallan, Alexander J; Adusumilli, Prasad S; Alchami, Fouad S; Attanoos, Richard; Brcic, Luka; Butnor, Kelly J; Galateau-Sallé, Françoise; Hiroshima, Kenzo; Kadota, Kyuichi; Klampatsa, Astero; Stang, Nolween Le; Lindenmann, Joerg; Litzky, Leslie A; Marchevsky, Alberto; Medeiros, Filomena; Montero, M Angeles; Moore, David A; Nabeshima, Kazuki; Pavlisko, Elizabeth N; Roggli, Victor L; Sauter, Jennifer L; Sharma, Anupama; Sheaff, Michael; Travis, William D; Vigneswaran, Wickii T; Vrugt, Bart; Walts, Ann E; Tjota, Melissa Y; Krausz, Thomas; Husain, Aliya N

    2018-04-01

    A recently described nuclear grading system predicted survival in patients with epithelioid malignant pleural mesothelioma. The current study was undertaken to validate the grading system and to identify additional prognostic factors. We analyzed cases of epithelioid malignant pleural mesothelioma from 17 institutions across the globe from 1998 to 2014. Nuclear grade was computed combining nuclear atypia and mitotic count into a grade of I-III using the published system. Nuclear grade was assessed by one pathologist for three institutions, the remaining were scored independently. The presence or absence of necrosis and predominant growth pattern were also evaluated. Two additional scoring systems were evaluated, one combining nuclear grade and necrosis and the other mitotic count and necrosis. Median overall survival was the primary endpoint. A total of 776 cases were identified including 301 (39%) nuclear grade I tumors, 354 (45%) grade II tumors and 121 (16%) grade III tumors. The overall survival was 16 months, and correlated independently with age (P=0.006), sex (0.015), necrosis (0.030), mitotic count (0.001), nuclear atypia (0.009), nuclear grade (<0.0001), and mitosis and necrosis score (<0.0001). The addition of necrosis to nuclear grade further stratified overall survival, allowing classification of epithelioid malignant pleural mesothelioma into four distinct prognostic groups: nuclear grade I tumors without necrosis (29 months), nuclear grade I tumors with necrosis and grade II tumors without necrosis (16 months), nuclear grade II tumors with necrosis (10 months) and nuclear grade III tumors (8 months). The mitosis-necrosis score stratified patients by survival, but not as well as the combination of necrosis and nuclear grade. This study confirms that nuclear grade predicts survival in epithelioid malignant pleural mesothelioma, identifies necrosis as factor that further stratifies overall survival, and validates the grading system across multiple

  17. Determination of chlorine in nuclear-grade uranium compounds

    International Nuclear Information System (INIS)

    Yang Chunqing; Liu Fuyun; Huang Dianfan

    1988-01-01

    The determination of chlorine in nuclear-grade uranium compounds is discribed. Chlorine is separated from uranium oxide pyrohydrolytically with stream of wet oxygen in a furnace at 800 ∼ 900 deg C. Chlorine is volatilized as hydrochloric acid, absorbed in a dilute alkaline solution and measured with chlorine-selective electrode. This method covers the concentration range of 10 ∼ 500 pm chlorine in uranium oxide. Precision of at least ± 10% and recovery of 85 ∼ 108% have been reported

  18. Comparison of Oxidation Characteristics of Selected Nuclear Graphite Grades

    International Nuclear Information System (INIS)

    Chi, Se Hwan; Kim, Gen Chan

    2010-02-01

    The oxidation behavior of some selected nuclear graphite grades (i.e., IG-110, IG-430, NBG-18, NBG-25) were compared in view of their filler coke type and the physical property of the grades. Oxidation rates were determined at six temperatures between 600 ∼ 960 .deg. C in air by using a three-zone vertical tube furnace at a 10 L/min air flow rate. The specimens were a cylinder with a 25.4 mm diameter and a 25.4 mm length. Results showed that, even though the four examined nuclear graphite grades showed a highly temperature-sensitive oxidation behavior through out the test temperature range of 600 ∼ 950 .deg. C, the differences between the grades were not significant. The oxidation rates determined for a 5∼10 % weight loss at the six temperatures were nearly the same except for 702 and 808 .deg. C, where the pitch coke graphites showed an apparent decrease in their oxidation rate, more so than the petroleum coke graphites. These effects of the coke type reduced or nearly disappeared with an increasing temperature. The average activation energy determined for 608 ∼ 808 .deg. C was 161.5 ± 7.3 kJ/mol, showing that the dominant oxidation reaction occurred by a chemical control

  19. Application of the graded management approach to Battelle's nuclear project

    International Nuclear Information System (INIS)

    Voth, C.B.

    1996-01-01

    Battelle's graded management approach provides an effective and efficient method to perform the Battelle Columbus Laboratories Decommissioning Project (BCLDP). The project is managed by Battelle under their US Nuclear Regulatory Commission (NRC) license but is partially funded by the US Department of Energy (DOE) on a cost-shared basis. Battelle's graded management approach adheres to the regulations and orders governing the BCLDP by the interaction of various plans, procedures, permits, and work instructions. By independent assessment, quality control, and worker training, Battelle has been able to establish a cost-effective approach to performing work and, at the same time, have a controlled checks and balance system to assure the proper safety considerations and project particulars are taken into account

  20. Specification for nuclear-grade beryllium oxide powder

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This specification defines the physical and chemical requirements of nuclear-grade beryllium oxide (BeO) powder to be used in fabricating nuclear components. 1.2 This specification does not include requirements for health and safety. , , It recognizes the material as a Class B poison and suggests that producers and users become thoroughly familiar with and comply to applicable federal, state, and local regulations and handling guidelines. 1.3 Special tests and procedures are given in Annex A1 and Annex A2. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

  1. Development of fracture toughness test method for nuclear grade graphite

    Energy Technology Data Exchange (ETDEWEB)

    Chang, C. H.; Lee, J. S.; Cho, H. C.; Kim, D. J.; Lee, D. J. [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2006-02-15

    Because of its high strength and stability at very high temperature, as well as very low thermal neutron absorption cross-section, graphite has been widely used as a structural material in Gas Cooled Reactors (GCR). Recently, many countries are developing the Very High Temperature gas cooled Reactor (VHTR) because of the potentials of hydrogen production, as well as its safety and viable economics. In VHTR, helium gas serves as the primary coolant. Graphite will be used as a reflector, moderator and core structural materials. The life time of graphite is determined from dimensional changes due to neutron irradiation, which closely relates to the changes of crystal structure. The changes of both lattice parameter and crystallite size can be easily measured by X-ray diffraction method. However, due to high cost and long time of neutron irradiation test, ion irradiation test is being performed instead in KAERI. Therefore, it is essential to develop the technique for measurement of ion irradiation damage of nuclear graphite. Fracture toughness of nuclear grade graphite is one of the key properties in the design and development of VHTR. It is important not only to evaluate the various properties of candidate graphite but also to assess the integrity of nuclear grade graphite during operation. Although fracture toughness tests on graphite have been performed in many laboratories, there have been wide variations in values of the calculated fracture toughness, due to the differences in the geometry of specimens and test conditions. Hence, standard test method for nuclear graphite is required to obtain the reliable fracture toughness values. Crack growth behavior of nuclear grade graphite shows rising R-curve which means the increase in crack growth resistance as the crack length increases. Crack bridging and microcracking have been proposed to be the dominant mechanisms of rising R-curve behavior. In this paper, the technique to measure the changes of crystallite size and

  2. Pre-grade academic project: Technicature in nuclear applications

    International Nuclear Information System (INIS)

    Daoud, Adrian; Garcia Blesa, Hernan M.; Lerner, Ana M.; Notari, Carla

    2009-01-01

    The increasing use of radiation and radioactive materials in the world today has created a demand of Specialized Nuclear Technicians. Both at the international level and locally in Argentina, such demand is expected to continue being significant for several years, and at present it already exceeds the offer of qualified personnel, which constitutes an interesting stimulus for graduates. For this reason, the Dan Beninson Nuclear Technology Institute has decided to accept the challenge of educating specialized technicians, and has thus designed a new pre-grade career: the Technicature in Nuclear Applications. The basis of this proposal is to design a three year high level specific training program in order to produce highly qualified technicians with a title issued by our Institute, offer the students a unique education with interesting working opportunities and required in all those areas that in one way or other are related to radiation and radioactive materials. No equivalent academic offer is in place today at university level. Due to the renaissance of nuclear activity and the subsequent increasing use of radioisotopes and radiation in technological applications as well as in energy generation, medical applications, agriculture, pharmacology, among others, it has become mandatory to train specialized human resources in this field. Having these goals in mind, our Institute has created this career, with the purpose of satisfying such request which will benefit the whole society. (author)

  3. Nuclear fuel technology - Determination of uranium in uranyl nitrate solutions of nuclear grade quality - Gravimetric method

    International Nuclear Information System (INIS)

    2003-01-01

    This International Standard specifies a precise and accurate gravimetric method for determining the mass fraction of uranium in uranyl nitrate solutions of nuclear grade quality containing more than 100 g/kg of uranium. Non-volatile impurities influence the accuracy of the method

  4. A microstructurally based fracture model for nuclear graphite

    International Nuclear Information System (INIS)

    Burchell, T.D.

    1991-01-01

    This paper reports the physical basis of, and assumptions behind, a fracture model for nuclear graphites. Microstructurally related inputs, such as filler particle size, filler particle fracture toughness (K Ic ), density, pore size distribution, number of pores and specimen geometry (size and volume), are utilized in the model. The model has been applied to two graphites, Great Lakes Carbon Corporation grade H-451 and Toyo Tanso grade IG-110. For each graphite, the predicted tensile failure probabilities are compared with experimental data generated using ASTM Standard C-749 tensile test specimens. The predicted failure probabilities are in close agreement with the experimental data, particularly in the case of the H-451. The model is also shown to qualitatively predict the influence on the failure probabilities of changes in filler particle size, density, pore size, pore size distribution, number of pores and specimen geometry (stressed volume). The good performance is attributed to the sound physical basis of the model, which recognizes the dominant role of porosity in controlling crack initiation and propagation during graphite fracture. 8 refs., 12 figs., 1 tab

  5. Relationships of nuclear, architectural and International Federation of Gynecology and Obstetrics grading systems in endometrial cancer.

    Science.gov (United States)

    Toptaş, Tayfun; Peştereli, Elif; Bozkurt, Selen; Erdoğan, Gülgün; Şimşek, Tayup

    2018-03-01

    To examine correlations among nuclear, architectural, and International Federation of Gynecology and Obstetrics (FIGO) grading systems, and their relationships with lymph node (LN) involvement in endometrioid endometrial cancer. Histopathology slides of 135 consecutive patients were reviewed with respect to tumor grade and LN metastasis. Notable nuclear atypia was defined as grade 3 nuclei. FIGO grade was established by raising the architectural grade (AG) by one grade when the tumor was composed of cells with nuclear grade (NG) 3. Correlations between the grading systems were analyzed using Spearman's rank correlation coefficients, and relationships of grading systems with LN involvement were assessed using logistic regression analysis. Correlation analysis revealed a significant and strongly positive relationship between FIGO and architectural grading systems (r=0.885, p=0.001); however, correlations of nuclear grading with the architectural (r=0.535, p=0.165) and FIGO grading systems (r=0.589, p=0.082) were moderate and statistically non-significant. Twenty-five (18.5%) patients had LN metastasis. LN involvement rates differed significantly between tumors with AG 1 and those with AG 2, and tumors with FIGO grade 1 and those with FIGO grade 2. In contrast, although the difference in LN involvement rates failed to reach statistical significance between tumors with NG 1 and those with NG 2, it was significant between NG 2 and NG 3 (p=0.042). Although all three grading systems were associated with LN involvement in univariate analyses, an independent relationship could not be established after adjustment for other confounders in multivariate analysis. Nuclear grading is significantly correlated with neither architectural nor FIGO grading systems. The differences in LN involvement rates in the nuclear grading system reach significance only in the setting of tumor cells with NG 3; however, none of the grading systems was an independent predictor of LN involvement.

  6. Determination of soluble carbon in nuclear grade boron carbide

    International Nuclear Information System (INIS)

    Vega Bustillos, J.O.; Gomes, R.; Camaro, J.; Zorzetto, F.; Domingues, P.; Riella, H.

    1990-05-01

    The present work describes two different techniques (manometric and wet chemical) for the soluble carbon determination in nuclear grade boron carbide. The techniques are based on the reaction of the boron carbide with a sulfocromic mixture, generating CO 2 . The techniques differ on the mode they do the measurement of CO 2 produced. By wet chemical technique the CO 2 is absorved in a barium hydroxide solution and is determinated by titration. In the manometric technique the CO 2 gas is measured using a McLeod gauge. The gas produced by the latter technique is analysed by mass spectrometry. The details of the analytical technique and the data obtained are discussed. (author) [pt

  7. Secondary resources processing in production of nuclear grade yellow cake

    International Nuclear Information System (INIS)

    Sivasubramanian, S.

    2009-01-01

    Full text: Recovering uranium in a cost competitive manner from sources other than the uranium ore is considered necessary from the point of view of meeting the strategic as well as the nuclear power programme need of the country. Globally, uranium is produced from ores which have more than 10 times uranium content compared to those available in India. Secondary sources of uranium are mostly defined by recycled uranium, from spent fuel of nuclear reactors, re-enriched depleted uranium tails, ex-military weapons grade uranium and stock piles for civilian use. Uranium production from secondary sources in India is largely dependent on processing of monazite, and to a smaller extent it is recovered from waste metallurgical slags generated by BARC and other private industries engaged in extracting niobium tantalum from the ores. The paper gives over view of the commercially successful processes of producing uranium from monazite and other secondary sources along with the details of setting up demonstration units for recovering uranium from wet phosphoric acid. The research and development work carried out to improve the cost economics of uranium production from monazite is also discussed as the total reported quantity of uranium associated with the monazite resources of the country is estimated at 30,000 tons of uranium metal (at the end of X Plan) compared to 75,000 ton of uranium in its primary ores

  8. Bombs grade 'spent' nuclear material removed from Uzbekistan

    International Nuclear Information System (INIS)

    2006-01-01

    now helping to convert the reactor to run on fuel that can not be used to make a nuclear weapon. The Agency is also developing lessons learned from this shipment to provide a basis for guidelines for future spent fuel shipments. 'It is no small undertaking to safely and securely repatriate the spent fuel. It invokes many technical, economic and legal issues which must be addressed before the shipment is successfully executed,' Mr. Adelfang said. This latest shipment follows the successful repatriation of nearly 11 kilograms of fresh highly enriched uranium from the Uzbek reactor in 2004. Over the past three years the IAEA has supported similar operations in other countries including Libya, Romania, Serbia and Montenegro, Bulgaria, Uzbekistan, Latvia and the Czech Republic to transfer HEU reactor fuel back to its country of origin. More than 100 research reactors around the world still run on weapons-grade HEU. The Agency is working with its Member States to convert their research reactors from HEU to using proliferation-resistant lower enriched fuel. International and national efforts have resulted in the full conversion of 33 research reactors. In conjunction with the US-initiated GTRI and other programmes, the IAEA is working to reduce and eventually eliminate international commerce in HEU for use in research reactors or critical assemblies. As part of its efforts, the IAEA also assists Member States to upgrade physical security and improve overall safety of their research reactors. A particular focus is on ageing or shut down reactors and their spent fuel storage facilities. (IAEA)

  9. Investigation of chloride-release of nuclear grade resin in PWR primary system coolant

    International Nuclear Information System (INIS)

    Cao Xiaoning; Li Yunde; Li Jinghong; Lin Fangliang

    1997-01-01

    A new preparation technique is developed for making the low-chloride nuclear-grade resin by commercial resin. The chloride remained in nuclear grade resin may release to PWR primary coolant. The amount of released chloride is depended on the concentration of boron, lithium, other anion impurities, and remained chloride concentration in resin

  10. Application of graded QA in the nuclear industry

    International Nuclear Information System (INIS)

    Churchill, G.F.

    1987-01-01

    All current schemes for grading of quality assurance are developments or variations on three themes; defining and grouping the planning and systematic actions which constitute the quality assurance approach, defining and classifying the safety, economic and other factors which influence the extent of quality assurance necessary, and using classification or grading schedules to relate grades of quality assurance to classes of factors. The codes and standards which define the actions needed for good management are listed and discussed. A typical equipment classification schedule or a light water reactor is shown. Contract interface documentation and surveillance requirements are discussed. (UK)

  11. Ductal carcinoma in situ of the breast (DCIS with heterogeneity of nuclear grade: prognostic effects of quantitative nuclear assessment

    Directory of Open Access Journals (Sweden)

    Fu Yuejiao

    2007-09-01

    Full Text Available Abstract Background Previously, 50% of patients with breast ductal carcinoma in situ (DCIS had more than one nuclear grade, and neither worst nor predominant nuclear grade was significantly associated with development of invasive carcinoma. Here, we used image analysis in addition to histologic evaluation to determine if quantification of nuclear features could provide additional prognostic information and hence impact prognostic assessments. Methods Nuclear image features were extracted from about 200 nuclei of each of 80 patients with DCIS who underwent lumpectomy alone, and received no adjuvant systemic therapy. Nuclear images were obtained from 20 representative nuclei per duct, from each of a group of 5 ducts, in two separate fields, for 10 ducts. Reproducibility of image analysis features was determined, as was the ability of features to discriminate between nuclear grades. Patient information was available about clinical factors (age and method of DCIS detection, pathologic factors (DCIS size, nuclear grade, margin size, and amount of parenchymal involvement, and 39 image features (morphology, densitometry, and texture. The prognostic effects of these factors and features on the development of invasive breast cancer were examined with Cox step-wise multivariate regression. Results Duplicate measurements were similar for 89.7% to 97.4% of assessed image features. For the pooled assessment with ~200 nuclei per patient, a discriminant function with one densitometric and two texture features was significantly (p Conclusion Image analysis provided reproducible assessments of nuclear features which quantitated differences in nuclear grading for patients. Quantitative nuclear image features indicated prognostically significant differences in DCIS, and may contribute additional information to prognostic assessments of which patients are likely to develop invasive disease.

  12. Commercial grade item (CGI) dedication of generators for nuclear safety related applications

    International Nuclear Information System (INIS)

    Das, R.K.; Hajos, L.G.

    1993-01-01

    The number of nuclear safety related equipment suppliers and the availability of spare and replacement parts designed specifically for nuclear safety related application are shrinking rapidly. These have made it necessary for utilities to apply commercial grade spare and replacement parts in nuclear safety related applications after implementing proper acceptance and dedication process to verify that such items conform with the requirements of their use in nuclear safety related application. The general guidelines for the commercial grade item (CGI) acceptance and dedication are provided in US Nuclear Regulatory Commission (NRC) Generic Letters and Electric Power Research Institute (EPRI) Report NP-5652, Guideline for the Utilization of Commercial Grade Items in Nuclear Safety Related Applications. This paper presents an application of these generic guidelines for procurement, acceptance, and dedication of a commercial grade generator for use as a standby generator at Salem Generating Station Units 1 and 2. The paper identifies the critical characteristics of the generator which once verified, will provide reasonable assurance that the generator will perform its intended safety function. The paper also delineates the method of verification of the critical characteristics through tests and provide acceptance criteria for the test results. The methodology presented in this paper may be used as specific guidelines for reliable and cost effective procurement and dedication of commercial grade generators for use as standby generators at nuclear power plants

  13. Ductal carcinoma in situ of the breast (DCIS) with heterogeneity of nuclear grade: prognostic effects of quantitative nuclear assessment

    International Nuclear Information System (INIS)

    Chapman, Judith-Anne W; Miller, Naomi A; Lickley, H Lavina A; Qian, Jin; Christens-Barry, William A; Fu, Yuejiao; Yuan, Yan; Axelrod, David E

    2007-01-01

    Previously, 50% of patients with breast ductal carcinoma in situ (DCIS) had more than one nuclear grade, and neither worst nor predominant nuclear grade was significantly associated with development of invasive carcinoma. Here, we used image analysis in addition to histologic evaluation to determine if quantification of nuclear features could provide additional prognostic information and hence impact prognostic assessments. Nuclear image features were extracted from about 200 nuclei of each of 80 patients with DCIS who underwent lumpectomy alone, and received no adjuvant systemic therapy. Nuclear images were obtained from 20 representative nuclei per duct, from each of a group of 5 ducts, in two separate fields, for 10 ducts. Reproducibility of image analysis features was determined, as was the ability of features to discriminate between nuclear grades. Patient information was available about clinical factors (age and method of DCIS detection), pathologic factors (DCIS size, nuclear grade, margin size, and amount of parenchymal involvement), and 39 image features (morphology, densitometry, and texture). The prognostic effects of these factors and features on the development of invasive breast cancer were examined with Cox step-wise multivariate regression. Duplicate measurements were similar for 89.7% to 97.4% of assessed image features. For the pooled assessment with ~200 nuclei per patient, a discriminant function with one densitometric and two texture features was significantly (p < 0.001) associated with nuclear grading, and provided 78.8% correct jackknifed classification of a patient's nuclear grade. In multivariate assessments, image analysis nuclear features had significant prognostic associations (p ≤ 0.05) with the development of invasive breast cancer. Texture (difference entropy, p < 0.001; contrast, p < 0.001; peak transition probability, p = 0.01), densitometry (range density, p = 0.004), and measured margin (p = 0.05) were associated with

  14. Large palpable ductal carcinoma in situ is Her-2 positive with high nuclear grade.

    Science.gov (United States)

    Monabati, Ahmad; Sokouti, Ali-Reza; Noori, Sadat Noori; Safaei, Akbar; Talei, Abd-Rasul; Omidvari, Shapoor; Azarpira, Negar

    2015-01-01

    Ductal carcinoma in situ (DCIS) of the breast is a heterogeneous group with variable clinical presentation. The exact molecular mechanism is not known why some ductal carcinomas may reach to such a large size but still remains in situ. Although, molecular classification of DCIS lesions and nuclear grading are important for identification of more aggressive lesions but it is not sufficient. Our aim was to examine the expression pattern of immunohistochemical (IHC) markers of ER, PR, HER-2 in palpable DCIS lesions and compare with clinicopathological findings. Our center is referral hospital from South of Iran. Samples were obtained from fifty four patients with a diagnosis of palpable DCIS. Equivocal (2+) case in HER-2 IHC testing was more characterized by chromogenic in situ hybridization. The positive frequency of HER2, ER, and PR was 92%, 48%, and 37% respectively. Palpable DCIS lesions were significantly more HER-2 positive (92%). The DCIS cases were more likely to be of high nuclear grade (grade III) and Her-2 positive cases were more likely to be of high nuclear grade than intermediate grade. All ER negative tumors had high nuclear grade. The Her-2 positivity is suggested as the most important factor responsible for marked in situ proliferation and production of palpable mass.

  15. Nuclear grade cable thermal life model by time temperature superposition algorithm based on Matlab GUI

    International Nuclear Information System (INIS)

    Lu Yanyun; Gu Shenjie; Lou Tianyang

    2014-01-01

    Background: As nuclear grade cable must endure harsh environment within design life, it is critical to predict cable thermal life accurately owing to thermal aging, which is one of dominant factors of aging mechanism. Purpose: Using time temperature superposition (TTS) method, the aim is to construct nuclear grade cable thermal life model, predict cable residual life and develop life model interactive interface under Matlab GUI. Methods: According to TTS, nuclear grade cable thermal life model can be constructed by shifting data groups at various temperatures to preset reference temperature with translation factor which is determined by non linear programming optimization. Interactive interface of cable thermal life model developed under Matlab GUI consists of superposition mode and standard mode which include features such as optimization of translation factor, calculation of activation energy, construction of thermal aging curve and analysis of aging mechanism., Results: With calculation result comparison between superposition and standard method, the result with TTS has better accuracy than that with standard method. Furthermore, confidence level of nuclear grade cable thermal life with TTS is higher than that with standard method. Conclusion: The results show that TTS methodology is applicable to thermal life prediction of nuclear grade cable. Interactive Interface under Matlab GUI achieves anticipated functionalities. (authors)

  16. Preparation of nuclear grade strongly basic anion exchange resin in hydroxide from

    International Nuclear Information System (INIS)

    Ke Weiqing

    1989-01-01

    The two-step transformation method was used to prepare 90 kg nuclear grade strongly basic anion exchange resins by using the industrial grade baking soda and caustic soda manufacutred by mercury-cathode electrolysis. The chloride and biscarbonate fraction on resin is 0.8% and 1.25% respectively, when the baking soda and caustic soda consumption is 8.6 and 13.7 times the total exchange capacity of the strongly basic resin

  17. Comparative analysis among X-ray mammographic findings, nuclear and histologic grading, and TNM staging of breast carcinoma

    International Nuclear Information System (INIS)

    Park, Jin Sook; Sung, Ki Joon; Cho, Mee Yon; Hong, In Soo; Kim, Myung Soon; Oh, Ki Keun

    1996-01-01

    The purpose of this study was to evaluate the prognosis of breast carcinoma by comparison with X-ray mammographic findings, nuclear and histologic grade, and TNM staging. We retrospectively reviewed 114 cases (113 patients) of breast carcinoma, analysing X-ray mammographic findings of all cases with regard to mass, calcification, and spiculation. In 80 cases of scirrhous invasive ductal breast carcinoma. Black's nuclear and Bloom-Richardson's histologic grade were also evaluated. Mammographic findings and nuclear and histologic grade were compared with TNM staging which might suggest the prognosis of breast carcinoma. X-ray mammographic findings (mass, calcification and spiculation) did not significantly correlate with T staging, but the clinical staging of the spiculation was advanced. These X-ray findings did not significantly correlate with the nuclear grading and the histologic grading. Nuclear grade did not correlate with T and M staging, but correlated significantly with N staging and clinical stage(p < 0.05). Histologic grade did not significantly correlate with TNM staging. The clinical staging of spiculation was advanced and nuclear grade correlated significantly with N stage and clinical staging. X-ray mammographic findings did not directly correlate with nuclear and histologic grading, but combined studies of the evaluation of mammographic findings and nuclear and histologic grade were useful for prognosing breast carcinoma

  18. Leveraging comprehensive baseline datasets to quantify property variability in nuclear-grade graphites

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, Mark C., E-mail: mark.carroll@inl.gov [Idaho National Laboratory, PO Box 1625, Idaho Falls, ID 83415-2213 (United States); Windes, William E.; Rohrbaugh, David T. [Idaho National Laboratory, PO Box 1625, Idaho Falls, ID 83415-2213 (United States); Strizak, Joseph P.; Burchell, Timothy D. [Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6088 (United States)

    2016-10-15

    Highlights: • An effort is underway to fully quantify the properties of nuclear-grade graphites. • Physical and mechanical properties of graphite are best characterized by distributions. • The Weibull distribution is most representative of graphite based on goodness-of-fit. • Fine-grained isomolded grades exhibit higher Weibull modulus values, indicative of more homogeneous properties. - Abstract: The full characterization of the physical and mechanical properties of candidate nuclear-grade graphites is highly dependent upon an understanding of the distribution of values that are inherent to graphite. Not only do the material properties of graphites vary considerably between grades owing to the raw materials sources, filler particle type and size, methods of compaction, and production process parameters, but variability is observed between billets of the same grade from a single batch and even across spatial positions within a single billet. Properly enveloping the expected properties of interest requires both a substantial amount of data to statistically capture this variability and a representative distribution capable of accurately describing the range of values. A two-parameter Weibull distribution is confirmed to be representative of the distribution of physical (density, modulus) and mechanical (compressive, flexure, and tensile strength) values in five different nuclear-grades of graphite. The fine-grained isomolded grades tend toward higher Weibull modulus and characteristic strength values, while the extruded grade being examined exhibits relatively large distributions in property values. With the number of candidate graphite specimens that can undergo full irradiation exposure and subsequent testing having limited feasibility with regard to economics and timely evaluations, a proper capture of the raw material variability in an unirradiated state can provide crucial supplementary resolution to the limited amount of available data on irradiated

  19. Standard Specification for Nuclear Grade Zirconium Oxide Pellets

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This specification applies to pellets of stabilized zirconium oxide used in nuclear reactors. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

  20. Chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade uranyl nitrate solutions

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    The standard covers analytical procedures to determine compliance of nuclear-grade uranyl nitrate solution to specifications. The following methods are described in detail: uranium by ferrous sulfate reduction-potassium dichromate titrimetry and by ignition gravimetry; specific gravity by pycnometry; free acid by oxalate complexation; thorium by the Arsenazo(III) (photometric) method; chromium by the diphenylcarbazide (photometric) method; molybdenum by the thiocyanate (photometric) method; halogens separation by steam distillation; fluorine by specific ion electrode; halogen distillate analysis: chloride, bromide and iodide by amperometric microtitrimetry; bromine by the fluorescein (photometric) method; sulfate sulfur by (photometric) turbidimetry; phosphorus by the molybdenum blue (photometric) method; silicon by the molybdenum blue (photometric) method; carbon by persulfate oxidation-acid titrimetry; nonvolatile impurities by spectrography; volatile impurities by rotating-disk spark spectrography; boron by emission spectrography; impurity elements by spark source mass spectrography; isotopic composition by multiple filament surface-ionization mass spectrometry; uranium-232 by alpha spectrometry; total alpha activity by direct alpha counting; fission product activity by beta and gamma counting; entrained organic matter by infrared spectrophotometry

  1. Standard specification for nuclear-grade zirconium oxide powder

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This specification defines the physical and chemical requirements for zirconium oxide powder intended for fabrication into shapes, either entirely or partially of zirconia, for use in a nuclear reactor core. 1.2 The material described herein shall be particulate in nature. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

  2. Role of nuclear grade graphite in controlling oxidation in modular HTGRs

    Energy Technology Data Exchange (ETDEWEB)

    Windes, Willaim [Idaho National Lab. (INL), Idaho Falls, ID (United States); Strydom, G. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Kane, J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Smith, R. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-11-01

    The passively safe High Temperature Gas-cooled Reactor (HTGR) design is one of the primary concepts considered for Generation IV and Small Modular Reactor (SMR) programs. The helium cooled, nuclear grade graphite moderated core achieves extremely high operating temperatures allowing either industrial process heat or electricity generation at high efficiencies. In addition to their neutron moderating properties, nuclear grade graphite core components provide excellent high temperature stability, thermal conductivity, and chemical compatibility with the high temperature nuclear fuel form. Graphite has been continuously used in nuclear reactors since the 1940’s and has performed remarkably well over a wide range of core environments and operating conditions. Graphite moderated, gas-cooled reactor designs have been safely used for research and power production purposes in multiple countries since the inception of nuclear energy development. However, graphite is a carbonaceous material, and this has generated a persistent concern that the graphite components could actually burn during either normal or accident conditions [ , ]. The common assumption is that graphite, since it is ostensibly similar to charcoal and coal, will burn in a similar manner. While charcoal and coal may have the appearance of graphite, the internal microstructure and impurities within these carbonaceous materials are very different. Volatile species and trapped moisture provide a source of oxygen within coal and charcoal allowing them to burn. The fabrication process used to produce nuclear grade graphite eliminates these oxidation enhancing impurities, creating a dense, highly ordered form of carbon possessing high thermal diffusivity and strongly (covalently) bonded atoms.

  3. Quantitative determination of impurities in nuclear grade aluminum by Flame-Atomic Absorption Spectrometry

    International Nuclear Information System (INIS)

    Jat, J.R.; Nayak, A.K.; Balaji Rao, Y.; Ravindra, H.R.

    2013-01-01

    The paper deals with quantitative determination of impurity elements in nuclear grade aluminum, used as fin tubes in research reactors, by Flame-Atomic Absorption Spectrometry (F-AAS). The results have been compared with those obtained by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) method. Experimental conditions used in both the methods are given in the paper. (author)

  4. Development of Necessary Technology for localizing of Nuclear Safety Grade I and C System

    International Nuclear Information System (INIS)

    Kwon, Kee Choon; Jang, Tong Il; Kim, Jung Tack

    2010-08-01

    Through KNICS and Nu-Tech 2012, a MMIS(Man-Machine Interface System) package for nuclear plants was localized and is expected to be applied to SUN 1,2 plants. This study is aimed to support the application of the MMIS package including the following technologies that meet strengthened regulation requirements and enhanced utility's performance requirements to nuclear plants. - Dedication to safety-grade computers and real time operating systems - The broadband communication network for safety information - Application of the automatic test for safety systems - Application of programmable logic controllers to nuclear plants - Development strategy for an integrated SW development tool for control device

  5. Heat treatments in a conventional steel to reproduce the microstructure of a nuclear grade steel

    International Nuclear Information System (INIS)

    Rosalio G, M.

    2014-01-01

    The ferritic steels used in the manufacture of pressurized vessels of Boiling Water Reactors (BWR) suffer degradation in their mechanical properties due to damage caused by the neutron fluxes of high energy bigger to a Mega electron volt (E> 1 MeV) generated in the reactor core. The materials with which the pressurized vessels of nuclear reactors cooled by light water are built correspond to low alloy ferritic steels. The effect of neutron irradiation on these steels is manifested as an increase in hardness, mechanical strength, with the consequent decrease in ductility, fracture toughness and an increase in temperature of ductile-brittle transition. The life of a BWR is 40 years, its design must be considered sufficient margin of safety because pressure forces experienced during operation, maintenance and testing of postulated accident conditions. It is necessary that under these conditions the vessel to behave ductile and likely to propagate a fracture is minimized. The vessels of light water nuclear reactors have a bainite microstructure. Specifically, the reactor vessels of the nuclear power plant of Laguna Verde (Veracruz, Mexico) are made of a steel Astm A-533, Grade B Class 1. At present they are carrying out some welding tests for the construction of a model of a BWR, however, to use nuclear grade steel such as Astm A-533 to carry out some of the welding tests, is very expensive; perform these in a conventional material provides basic information. Although the microstructure present in the conventional material does not correspond exactly to the degree of nuclear material, it can take of reference. Therefore, it is proposed to conduct a pilot study to establish the thermal treatment that reproduces the microstructure of nuclear grade steel, in conventional steel. The resulting properties of the conventional steel samples will be compared to a JRQ steel, that is a steel Astm A-533, Grade B Class 1, provided by IAEA. (Author)

  6. Weapons-grade nuclear material - open questions of a safe disposal

    International Nuclear Information System (INIS)

    Closs, K.D.; Giraud, J.P.; Grill, K.D.; Hensing, I.; Hippel, F. von; Holik, J.; Pellaud, B.

    1995-01-01

    There are suitable technologies available for destruction of weapons-grade uranium and plutonium. Weapons-grade uranium, consisting to 90% of the isotope U-235, can be diluted with the uranium isotope U-238 to make it non-weapons-grade, but it will then still be a material that can be used as a fuel in civil nuclear reactors. For safe plutonium disposal, several options are under debate. There is for instance a process called ''reverse reprocessing'', with the plutonium being blended with high-level radioactive fission products and then being put into a waste form accepted for direct ultimate disposal. The other option is to convert weapons-grade plutonium into MOX nuclear fuel elements and then ''burn'' them in civil nuclear power reactors. This is an option favoured by many experts. Such fuel elements should stay for a long time in the reactor core in order to achieve high burnups, and should then be ready for ultimate disposal. This disposal pathway offers essential advantages: the plutonium is used up or depleted as a component of reactor fuel, and thus is no longer available for illegal activities, and it serves as an energy source for power generation. (orig./HP) [de

  7. Ductal carcinoma of breast: nuclear grade as a predictor of S-phase fraction.

    Science.gov (United States)

    Dabbs, D J

    1993-06-01

    Nuclear grade (NG) and S-phase fraction (SPF) are established independent prognostic variables for ductal breast carcinomas. Nuclear grade can be assigned by a pathologist in a simple fashion during histopathologic evaluation of the tumor, while SPF requires flow cytometric evaluation of tumor samples. This prospective study was undertaken to determine whether elevated SPF could be predicted from NG alone and how NG and SPF correlate with c-erbB-2 expression. Eighty-two breast carcinomas of ductal type were assigned an NG of low (grade 1 or grade 2) or high (grade 3). S-phase fraction was recorded initially from fresh-frozen tissue samples and was designated as either low SPF (below the value designated as the cutoff for elevated SPF) or high SPF (a value at or greater than the cutoff value). On fresh tissue the NG predicted the range of SPF (low or high) in 89% of cases. Four percent of the cases that did not correlate could definitely be attributed to sample error. The remaining 7% that did not correlate could have been due to sample error, specimen quality, or tumor heterogeneity, as demonstrated by reversal of SPF range as performed on paraffin blocks of tumor. Eighty-eight percent of the tumors positive for c-erbB-2 were NG 3 and 12% were NG 2. All c-erbB-2 tumors were aneuploid. This study demonstrates the importance of carefully assigning NGs on tissue and indicates the importance of reviewing flow cytometric data side by side with histopathologic parameters to detect discrepancies between these two modalities. Careful nuclear grading assignment can accurately predict the range of SPF.

  8. The application of CPLD in online nuclear detection meter of ore grade

    International Nuclear Information System (INIS)

    Yin Yiqiang; Yin Deyou; Gong Yalin; Shang Qingmin; Xiao Xiandong; Zhou Hongjun; Yu Haiming

    2010-01-01

    The pulse height analysis circuit for nuclear pulse signals is an important function cell of online nuclear detection meter, requiring high speed and credible logic circuit to eliminate the signal pileup rejection, overload detection, instrumentation measurement dead time on the adverse effects of spectrum. In order to improve the performance of nuclear detection meter, some function circuits are used, such as live time offset, overload detection and pileup rejection. The CPLD and multi single-channel spectrum measurement method used in ore grade nuclear instrumentation, eliminating the pileup, overload signal and accurately compensated the measurement of dead time, thus the circuit functions above are carried out credibly and the meter detection accuracy is improved drastically. (authors)

  9. Weldability and microstructural analysis of nuclear-grade austenitic stainless steels

    International Nuclear Information System (INIS)

    Lee, C.H.

    1988-01-01

    This study evaluated the hot-ductility response, and hot-cracking susceptibility (fusion-zone solidification cracking and HAZ liquation cracking) of modified nuclear-grade and standard austenitic stainless steels. Extensive microstructural characterization using state-of-the-art analytical electron microscopy (TEM and STEM) as well as SEM (EDAX) and OLM was performed to correlate the material behavior with metallurgical characteristics. In addition, studies of the effect of Si, N, and rare earth elements on hot-cracking susceptibility, significance of the ductility dip phenomena and backfilled solidification cracks were also performed. Furthermore, based on the metallurgical evaluation, the possible mechanisms involved in solidification cracking and HAZ liquation cracking of the modified alloys are proposed. Finally, the optimized chemical specifications and requirements for nuclear-grade stainless steels are also suggested

  10. Technical criteria for terminating or reducing domestic safeguards on low-grade special nuclear material

    International Nuclear Information System (INIS)

    Crawford, D.W.

    1996-01-01

    A graded table for terminating or reducing domestic safeguards has been developed for use by programs and facilities within the Department of Energy in decisions regarding the need for or levels of protection of low-grade nuclear materials. Contained in this table are technical criteria which can allow for complete removal of safeguards over many special nuclear material forms and concentrations of typical low-grade materials either currently located at generating or processing sites and materials which may arise from processing operations related to stabilization and disposition activities. In addition, these criteria include higher concentration levels which may warrant maintaining some level of (albeit reduced) security on low-grade materials while allowing reductions in materials control and accountability requirements. These reductions can range from complete removal of these materials from materials control and accountability requirements such as measurements, physical inventories and recordkeeping, to deferring these measurements and physical inventories until a time that either the material is removed from the site or resubmitted for processing. It is important to note that other conditions contained in current Departmental safeguards and security policy be met prior to safeguards termination or reduction

  11. Fusion reactor cost reductions by employing non-nuclear grade components

    International Nuclear Information System (INIS)

    Bourque, R.F.; Maya, I.; Schultz, K.R.; Sonn, D.L.; Wise, R.K.

    1987-09-01

    The Cascade inertial confinement fusion reactor fits the requirements of low radioactive inventories and inherent safety and is therefore a candidate for non-nuclear construction throughout. This reactor consists of a rotating blanket of ceramic granules that absorb the energy from D-T target explosions occurring along the rotational axis. Laser energy is beamed in axially from both ends. Two cost estimates were made for an 815 MWe Cascade power plant. One was based on an ''all conventional'' plant, which is constructed and costed using well-established, conventional fossil power plant methods. The second was a ''nuclear plus conventional'' design, constructed and costed using a combination of fossil and fission reactor plant methods and standards that would be typical of advanced fission reactors. The total capital requirements for the ''all conventional'' construction plant were estimated in 1985 dollars at $1490 M, including indirect costs. Similarly, the ''nuclear plus conventional'' construction plant was estimated at $1940 M. The savings of $450 M (23%) represents strictly the difference between Cascade ICF power plants designed and constructed to nuclear safety-related requirements versus all non-nuclear. This example clearly shows that, if fusion plants can take advantage of low activation materials and inherent safety features to eliminate the need for nuclear-related expenses, then such plants may have economic advantages over nuclear-grade systems. 13 refs., 1 fig., 5 tabs

  12. Standard test methods for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade uranyl nitrate solutions

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1999-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade uranyl nitrate solution to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Determination of Uranium 7 Specific Gravity by Pycnometry 15-20 Free Acid by Oxalate Complexation 21-27 Determination of Thorium 28 Determination of Chromium 29 Determination of Molybdenum 30 Halogens Separation by Steam Distillation 31-35 Fluoride by Specific Ion Electrode 36-42 Halogen Distillate Analysis: Chloride, Bromide, and Iodide by Amperometric Microtitrimetry 43 Determination of Chloride and Bromide 44 Determination of Sulfur by X-Ray Fluorescence 45 Sulfate Sulfur by (Photometric) Turbidimetry 46 Phosphorus by the Molybdenum Blue (Photometric) Method 54-61 Silicon by the Molybdenum Blue (Photometric) Method 62-69 Carbon by Persulfate Oxidation-Acid Titrimetry 70 Conversion to U3O8 71-74 Boron by ...

  13. Standard test methods for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade plutonium nitrate solutions

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade plutonium nitrate solutions to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Plutonium by Controlled-Potential Coulometry Plutonium by Amperometric Titration with Iron(II) Plutonium by Diode Array Spectrophotometry Free Acid by Titration in an Oxalate Solution 8 to 15 Free Acid by Iodate Precipitation-Potentiometric Titration Test Method 16 to 22 Uranium by Arsenazo I Spectrophotometric Test Method 23 to 33 Thorium by Thorin Spectrophotometric Test Method 34 to 42 Iron by 1,10-Phenanthroline Spectrophotometric Test Method 43 to 50 Impurities by ICP-AES Chloride by Thiocyanate Spectrophotometric Test Method 51 to 58 Fluoride by Distillation-Spectrophotometric Test Method 59 to 66 Sulfate by Barium Sulfate Turbidimetric Test Method 67 to 74 Isotopic Composition by Mass Spectrom...

  14. The 'overlooked trio' of hypothetical terrorist nuclear weapons - reactor grade plutonium, neptunium-237 and tritium

    International Nuclear Information System (INIS)

    Sholly, S.

    2002-01-01

    Full text: Considerations revolving around physical protection of nuclear material are quite commonly and naturally focused on protecting weapons-grade plutonium (WGPu) and highly enriched uranium (HEU) from theft and diversion. These two materials are the center of attention because of their well-known (and demonstrated) potential for use in first-generation nuclear explosive devices of which potential terrorists are widely thought to be capable. They are also the center of attention because of retirements of these materials from military use as the Russian Federation and the United States reduce the number of nuclear weapons in their arsenals. Three other materials - an 'overlooked trio' - must also be borne in mind within this context: (1) reactor-grade plutonium (RGPu); (2) neptunium-237 (Np-237); and (3) tritium (H-3). Although there are still some authorities who either contend that RGPu cannot be used in a nuclear explosive or that there are (for a terrorist) insurmountable difficulties in doing so, the knowledgeable scientific and technical community, recognizes the potential utility of RGPu for hypothetical terrorist nuclear devices. A much smaller community of experts recognizes the usefulness of Np-237 for nuclear devices, but Np-237 is as straight-forwardly and easily usable as HEU and similarly abundant (but not often in separated form). Tritium can be used (with a modest increase in design sophistication) in a conventional first-generation nuclear device with any of the weapons-usable materials (WGPu, HEU, RGPu or Np-237) to increase the yield and/or increase the reliability of a non-fizzle yield. Given the presence of RGPu and Np-237 in abundant quantities in spent commercial reactor fuel, widely available knowledge of how to separate these materials, and a world-wide total of more than 400 nuclear power plants, spent reactor fuel also requires stringent controls. This is especially true of old spent fuel which has far less radiation dose

  15. The Application of materials attractiveness in a graded approach to nuclear materials security

    International Nuclear Information System (INIS)

    Ebbinghaus, B.; Bathke, C.; Dalton, D.; Murphy, J.

    2013-01-01

    The threat from terrorist groups has recently received greater attention. In this paper, material quantity and material attractiveness are addressed through the lens of a minimum security strategy needed to prevent the construction of a nuclear explosive device (NED) by an adversary. Nuclear materials are placed into specific security categories (3 or 4 categories) , which define a number of security requirements to protect the material. Materials attractiveness can be divided into four attractiveness levels, High, Medium, Low, and Very Low that correspond to the utility of the material to the adversary and to a minimum security strategy that is necessary to adequately protect the nuclear material. We propose a graded approach to materials attractiveness that recognizes for instance substantial differences in attractiveness between pure reactor-grade Pu oxide (High attractiveness) and fresh MOX fuel (Low attractiveness). In either case, an adversary's acquisition of a Category I quantity of plutonium would be a major incident, but the acquisition of Pu oxide by the adversary would be substantially worse than the acquisition of fresh MOX fuel because of the substantial differences in the time and complexity required of the adversary to process the material and fashion it into a NED

  16. The Application of materials attractiveness in a graded approach to nuclear materials security

    Energy Technology Data Exchange (ETDEWEB)

    Ebbinghaus, B. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States); Bathke, C. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Dalton, D.; Murphy, J. [National Nuclear Security Administration, US Department of Energy, 1000 Independent Ave., S. W. Washington, DC 20585 (United States)

    2013-07-01

    The threat from terrorist groups has recently received greater attention. In this paper, material quantity and material attractiveness are addressed through the lens of a minimum security strategy needed to prevent the construction of a nuclear explosive device (NED) by an adversary. Nuclear materials are placed into specific security categories (3 or 4 categories) , which define a number of security requirements to protect the material. Materials attractiveness can be divided into four attractiveness levels, High, Medium, Low, and Very Low that correspond to the utility of the material to the adversary and to a minimum security strategy that is necessary to adequately protect the nuclear material. We propose a graded approach to materials attractiveness that recognizes for instance substantial differences in attractiveness between pure reactor-grade Pu oxide (High attractiveness) and fresh MOX fuel (Low attractiveness). In either case, an adversary's acquisition of a Category I quantity of plutonium would be a major incident, but the acquisition of Pu oxide by the adversary would be substantially worse than the acquisition of fresh MOX fuel because of the substantial differences in the time and complexity required of the adversary to process the material and fashion it into a NED.

  17. Biaxial testing for nuclear grade graphite by ball on three balls assessment

    International Nuclear Information System (INIS)

    Mohd Reusmaazran Yusof; Yusof Abdullah

    2012-01-01

    Nuclear grade (high-purity) graphite for fuel element and moderator material in Advanced Gas Cooling Reactors (AGR) displays large scatter in strength and a non-linear stress-strain response from the damage accumulation. These responses can be characterized as quasi-brittle behaviour. Current assessments of fracture in core graphite components are based on the linear elastic approximation and thus represent a major assumption. The quasi-brittle behaviour gives challenge to assess the real nuclear graphite component. The selected test method would help to bridge the gap between microscale to macro-scale in real reactor component. The small scale tests presented here can contribute some statistical data to manifests the failure in real component. The evaluation and choice of different solution design of biaxial test will be discussed in this paper. The ball on-three ball test method was used for assessment test follows by numerous of analytical method. The results shown that biaxial strength of the EY9 grade graphite depends on the method used for evaluation. Some of the analytical methods use to calculate biaxial strength were found not to be valid and therefore should not be used to assess the mechanical properties of nuclear graphite. (author)

  18. Determination of uranium in uranyl nitrate solutions of nuclear grade quality - Gravimetric method

    International Nuclear Information System (INIS)

    1990-01-01

    This international Standard specifies a precise and accurate gravimetric method for determining the uranium content in uranyl nitrate product solutions of nuclear grade quality at concentrations above 100 g/l of uranium. Non-volatile impurities influence the accuracy of the method. Uranyl nitrate is converted into uranium octoxide (U 3 O 8 ) by ignition in air to constant mass at 900 deg. C ± 10 deg. C. Calculation of the uranium content in the sample using a gravimetric conversion factor which depends on the isotopic composition of the uranium. The isotopic composition is determined by mass spectrometry

  19. Determination of chlorine in nuclear-grade uranium compounds by ion-selective electrode

    International Nuclear Information System (INIS)

    Yang Chunqing; Liu Fuyun; Huang Dianfan.

    1989-01-01

    The determination of microamount chlorine in nuclear-grade uranium compounds is described. Chlorine is separated from uranium oxide pyrohydrolytically with stream of wet oxygen in a furnace at 800-900 deg C. Chlorine is volatilized as hydrochloric acid, which then is absorbed in a dilute alkaline solution and measured with chlorine selective electrode. This method covers the concentration range of 10-500 ppm chlorine in uranium oxide. The relative standard diviation is better than 10% and recovery of 85-108% has been reported

  20. Adenocarcinoma predominant pattern subtyping and nuclear grading in cytology: Is there a role in prognostication of advanced pulmonary adenocarcinomas?

    Science.gov (United States)

    Nambirajan, A; Kaur, H; Jangra, K; Kaur, K; Madan, K; Mathur, S R; Iyer, V K; Jain, D

    2018-04-01

    Primary lung adenocarcinomas (ADs) show varied architectural patterns, and pattern-based subtyping of ADs is currently recommended due to prognostic implications. Predicting AD patterns on cytology is challenging; however, cytological nuclear features appear to correlate with histological grade and survival in early stage lung ADs. The feasibility and value of AD pattern prediction and nuclear grading on cytology in advanced lung ADs is not known. We aimed to predict patterns and analyse nuclear features on cytology and evaluate their role in prognostication. One-hundred patients of Stage III/IV lung AD with available matched cytology and histology samples were included. Cyto-patterns based on cell arrangement patterns (flat sheets vs three-dimensional clusters vs papillae) and cyto-nuclear score based on nuclear features (size, shape, contour), nucleoli (macronucleoli vs prominent vs inconspicuous), and nuclear chromatin were determined, and correlated with predominant histological-pattern observed on the matched small biopsy and outcome. Higher cyto-nuclear scores were observed with high-grade histo-patterns (solid, micropapillary and cribriform), while the predicted cyto-patterns did not correspond to the predominant pattern on histology in 77% cases. Highest cyto-histo agreement was observed for solid pattern (72%). High grade histo-patterns and cyto-nuclear scores > 3 showed a trend towards inferior survival (not significant). Nuclear grade scoring on cytology is simple to perform, and is predictive of high grade patterns. Its inclusion in routine reporting of cytology samples of lung ADs may be valuable. © 2018 John Wiley & Sons Ltd.

  1. Rapid screening of nuclear grade zirconium silicate without separation of hafnium from the bulk matrix

    International Nuclear Information System (INIS)

    Venkatesh, Manisha; Sharma, P.K.; Avhad, D.K.; Basu, H.; Singhal, R.K.; Reddy, A.V.R.

    2014-01-01

    Zirconium silicate, also zirconium orthosilicate, (ZrSiO 4 ) is a chemical compound, and occurs in nature as zircon, a silicate mineral. The concentration of Hafnium in nuclear grade Zirconium must be less than 0.2% w/w of Zr. In view of this it must be accurately chemically characterized before issuing a certification for export under non nuclear category. As the chemistry of Zr and Hf is similar, it is difficult to separate Hf by direct wet chemical method. During this work, concentration of Hf in zirconium silicate was measured by Field Portable X-ray Fluorescence (FPXRF) and results obtained were validated by using detailed chemical method. FPXRF spectrometry has become a common analytical technique for on-site screening and fast turnaround analysis of contaminant elements in environmental samples

  2. Qualifying commercial grade instruments for use in nuclear power generating stations

    International Nuclear Information System (INIS)

    Lamothe, R.J.; Scally, C.R.

    1983-01-01

    Nuclear environmental qualification of instrumentation has been successfully accomplished by many commercial grade equipment manufacturers. This paper was prepared as a guide to those manufacturers who want some insight into a qualification program. The areas addressed are the regulations and documents, the qualification program, and a case history of a chart recorder qualifications. The principal standards relating to a nuclear qualification program are IEEE Std. 323-1974 IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations, IEEE Std. 344-1975 IEEE Recommended Practices for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations and 10CFR50.49. Previously NUREG 0588 Interim Staff Position on Environmental Qualification of Safety-Related Equipment. These define the intent and purpose of the qualification. The qualification program itself consists of several distinct parts which require explanation, including the determination of qualified life, choice of test samples, selection of appropriate acceptance criteria, aging program, radiation testing, seismic testing, abnormal environment tests and others. The case history illustrates the qualification program and the thought processes involved

  3. Nuclear Kaiso expression is associated with high grade and triple-negative invasive breast cancer.

    Directory of Open Access Journals (Sweden)

    Jeroen F Vermeulen

    Full Text Available Kaiso is a BTB/POZ transcription factor that is ubiquitously expressed in multiple cell types and functions as a transcriptional repressor and activator. Little is known about Kaiso expression and localization in breast cancer. Here, we have related pathological features and molecular subtypes to Kaiso expression in 477 cases of human invasive breast cancer. Nuclear Kaiso was predominantly found in invasive ductal carcinoma (IDC (p = 0.007, while cytoplasmic Kaiso expression was linked to invasive lobular carcinoma (ILC (p = 0.006. Although cytoplasmic Kaiso did not correlate to clinicopathological features, we found a significant correlation between nuclear Kaiso, high histological grade (p = 0.023, ERα negativity (p = 0.001, and the HER2-driven and basal/triple-negative breast cancers (p = 0.018. Interestingly, nuclear Kaiso was also abundant in BRCA1-associated breast cancer (p<0.001 and invasive breast cancer overexpressing EGFR (p = 0.019. We observed a correlation between nuclear Kaiso and membrane-localized E-cadherin and p120-catenin (p120 (p<0.01. In contrast, cytoplasmic p120 strongly correlated with loss of E-cadherin and low nuclear Kaiso (p = 0.005. We could confirm these findings in human ILC cells and cell lines derived from conditional mouse models of ILC. Moreover, we present functional data that substantiate a mechanism whereby E-cadherin controls p120-mediated relief of Kaiso-dependent gene repression. In conclusion, our data indicate that nuclear Kaiso is common in clinically aggressive ductal breast cancer, while cytoplasmic Kaiso and a p120-mediated relief of Kaiso-dependent transcriptional repression characterize ILC.

  4. Study on the dynamic recrystallization model and mechanism of nuclear grade 316LN austenitic stainless steel

    International Nuclear Information System (INIS)

    Wang, Shenglong; Zhang, Mingxian; Wu, Huanchun; Yang, Bin

    2016-01-01

    In this study, the dynamic recrystallization behaviors of a nuclear grade 316LN austenitic stainless steel were researched through hot compression experiment performed on a Gleeble-1500 simulator at temperatures of 900–1250 °C and strain rates of 0.01–1 s −1 . By multiple linear regressions of the flow stress-strain data, the dynamic recrystallization mathematical models of this steel as functions of strain rate, strain and temperature were developed. Then these models were verified in a real experiment. Furthermore, the dynamic recrystallization mechanism of the steel was determined. The results indicated that the subgrains in this steel are formed through dislocations polygonization and then grow up through subgrain boundaries migration towards high density dislocation areas and subgrain coalescence mechanism. Dynamic recrystallization nucleation performs in grain boundary bulging mechanism and subgrain growth mechanism. The nuclei grow up through high angle grain boundaries migration. - Highlights: •Establish the DRX mathematical models of nuclear grade 316LN stainless steel •Determine the DRX mechanism of this steel •Subgrains are formed through dislocations polygonization. •Subgrains grow up through subgrain boundaries migration and coalescence mechanism. •DRX nucleation performs in grain boundary bulging mechanism and subgrain growth mechanism.

  5. Role of Nuclear Morphometry in Breast Cancer and its Correlation with Cytomorphological Grading of Breast Cancer: A Study of 64 Cases.

    Science.gov (United States)

    Kashyap, Anamika; Jain, Manjula; Shukla, Shailaja; Andley, Manoj

    2018-01-01

    Fine needle aspiration cytology (FNAC) is a simple, rapid, inexpensive, and reliable method of diagnosis of breast mass. Cytoprognostic grading in breast cancers is important to identify high-grade tumors. Computer-assisted image morphometric analysis has been developed to quantitate as well as standardize various grading systems. To apply nuclear morphometry on cytological aspirates of breast cancer and evaluate its correlation with cytomorphological grading with derivation of suitable cutoff values between various grades. Descriptive cross-sectional hospital-based study. This study included 64 breast cancer cases (29 of grade 1, 22 of grade 2, and 13 of grade 3). Image analysis was performed on Papanicolaou stained FNAC slides by NIS -Elements Advanced Research software (Ver 4.00). Nuclear morphometric parameters analyzed included 5 nuclear size, 2 shape, 4 texture, and 2 density parameters. Nuclear size parameters showed an increase in values with increasing cytological grades of carcinoma. Nuclear shape parameters were not found to be significantly different between the three grades. Among nuclear texture parameters, sum intensity, and sum brightness were found to be different between the three grades. Nuclear morphometry can be applied to augment the cytology grading of breast cancer and thus help in classifying patients into low and high-risk groups.

  6. Nuclear grade and DNA ploidy in stage IV breast cancer with only visceral metastases at initial diagnosis.

    Science.gov (United States)

    De Lena, M; Barletta, A; Marzullo, F; Rabinovich, M; Leone, B; Vallejo, C; Machiavelli, M; Romero, A; Perez, J; Lacava, J; Cuevas, M A; Rodriguez, R; Schittulli, F; Paradisco, A

    1996-01-01

    The presence of early metastases to distant sites in breast cancer patients is an infrequent event whose mechanisms are still not clear. The aim of this study was to evaluate the biologic and clinical role of DNA ploidy and cell nuclear grade of primary tumors in the metastatic process of a series of stage IV previously untreated breast cancer patients with only visceral metastases. DNA flow cytometry analysis on paraffin-embedded material and cell nuclear grading of primary tumors was performed on a series of 50 breast cancer patients with only visceral metastases at the time of initial diagnosis. Aneuploidy was found in 28/46 (61%) of evaluable cases and was independent of site of involvement, clinical response, time of progression and overall survival of patients. Of the 46 cases evaluable for nuclear grade, 5 (11%), 16 (35%) and 25 (54%) were classified as G1 (well-differentiated) G2 and G3, respectively. Nuclear grade also was unrelated to response to therapy and overall survival, whereas time to progression was significantly longer in G1-2 than G3 tumors with the logrank test (P < 0.03) and multivariate analysis. Our results seem to stress the difficulty to individualize different prognostic subsets from a series of breast cancer patients with only visceral metastases at initial diagnosis according to DNA flow cytometry and nuclear grade.

  7. Kinetics of Chronic Oxidation of NBG-17 Nuclear Graphite by Water Vapor

    Energy Technology Data Exchange (ETDEWEB)

    Contescu, Cristian I [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burchell, Timothy D [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mee, Robert [Univ. of Tennessee, Knoxville, TN (United States)

    2015-05-01

    This report presents the results of kinetic measurements during accelerated oxidation tests of NBG-17 nuclear graphite by low concentration of water vapor and hydrogen in ultra-high purity helium. The objective is to determine the parameters in the Langmuir-Hinshelwood (L-H) equation describing the oxidation kinetics of nuclear graphite in the helium coolant of high temperature gas-cooled reactors (HTGR). Although the helium coolant chemistry is strictly controlled during normal operating conditions, trace amounts of moisture (predictably < 0.2 ppm) cannot be avoided. Prolonged exposure of graphite components to water vapor at high temperature will cause very slow (chronic) oxidation over the lifetime of graphite components. This behavior must be understood and predicted for the design and safe operation of gas-cooled nuclear reactors. The results reported here show that, in general, oxidation by water of graphite NBG-17 obeys the L-H mechanism, previously documented for other graphite grades. However, the characteristic kinetic parameters that best describe oxidation rates measured for graphite NBG-17 are different than those reported previously for grades H-451 (General Atomics, 1978) and PCEA (ORNL, 2013). In some specific conditions, certain deviations from the generally accepted L-H model were observed for graphite NBG-17. This graphite is manufactured in Germany by SGL Carbon Group and is a possible candidate for the fuel elements and reflector blocks of HTGR.

  8. Some aspects of a technology of processing weapons grade plutonium to nuclear fuel

    International Nuclear Information System (INIS)

    Bibilashvili, Y.; Glagovsky, E.M.; Zakharkin, B.S.; Orlov, V.K.; Reshetnikov, F.G.; Rogozkin, B.G.; Soloni-N, M.I.

    2000-01-01

    The concept by Russia to use fissile weapons-grade materials, which are being recovered from nuclear pits in the process of disarmament, is based on an assessment of weapons-grade plutonium as an important energy source intended for use in nuclear power plants. However, in the path of involving plutonium excessive from the purposes of national safety into industrial power engineering there are a lot of problems, from which effectiveness and terms of its disposition are being dependent upon. Those problems have political, economical, financial and environmental character. This report outlines several technology problems of processing weapons-grade metallic plutonium into MOX-fuel for reactors based on thermal and fast neutrons, in particular, the issue of conversion of the metal into dioxide from the viewpoint of fabrication of pelletized MOX-fuel. The processing of metallic weapons-grade plutonium into nuclear fuel is a rather complicated and multi-stage process, every stage of which is its own production. Some of the stages are absent in production of MOX-fuel, for instance the stage of the conversion, i.e. transferring of metallic plutonium into dioxide of the ceramic quality. At this stage of plutonium utilization some tasks must be resolved as follows: I. As a result of the conversion, a material purified from ballast and radiogenic admixtures has to be obtained. This one will be applied to fabricate pelletized MOX-fuel going from morphological, physico-mechanical and technological properties. II. It is well known that metallic gallium, which is used as an alloying addition in weapons-grade plutonium, actively reacts with multiple metals. Therefore, an important issue is to study the effect of gallium on the technology of MOX-fuel production, quality of the pellets, as well as the interaction of gallium oxide with zirconium and steel shells of fuel elements depending upon the content of gallium in the fuel. The rate of the interaction of gallium oxide

  9. Verification Results of Safety-grade Optical Modem for Core Protection Calculator (CPC) in Korea Standard Nuclear Power Plant (KSNP)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jangyeol; Son, Kwangseop; Lee, Youngjun; Cheon, Sewoo; Cha, Kyoungho; Lee, Jangsoo; Kwon, Keechoon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    We confirmed that the coverage criteria for a safety-grade optical modem of a Core Protection Calculator is satisfactory using a traceability analysis matrix between high-level requirements and lower-level system test case data set. This paper describes the test environment, test components and items, a traceability analysis, and system tests as a result of system verification and validation based on Software Requirement Specifications (SRS) for a safety-grade optical modem of a Core Protection Calculator (CPC) in a Korea Standard Nuclear Power Plant (KSNP), and Software Design Specifications (SDS) for a safety-grade optical modem of a CPC in a KSNP. All tests were performed according to the test plan and test procedures. Functional testing, performance testing, event testing, and scenario based testing for a safety-grade optical modem of a Core Protection Calculator in a Korea Standard Nuclear Power Plant as a thirty-party verifier were successfully performed.

  10. Commercial grade item (CGI) dedication of MDR relays for nuclear safety related applications

    Science.gov (United States)

    Das, Ranjit K.; Julka, Anil; Modi, Govind

    1994-08-01

    MDR relays manufactured by Potter & Brumfield (P&B) have been used in various safety related applications in commercial nuclear power plants. These include emergency safety features (ESF) actuation systems, emergency core cooling systems (ECCS) actuation, and reactor protection systems. The MDR relays manufactured prior to May 1990 showed signs of generic failure due to corrosion and outgassing of coil varnish. P&B has made design changes to correct these problems in relays manufactured after May 1990. However, P&B does not manufacture the relays under any 10CFR50 Appendix B quality assurance (QA) program. They manufacture the relays under their commercial QA program and supply these as commercial grade items. This necessitates CGI Dedication of these relays for use in nuclear-safety-related applications. This paper presents a CGI dedication program that has been used to dedicate the MDR relays manufactured after been used to dedicate the MDR relays manufactured after May 1990. The program is in compliance with current Nuclear Regulatory Commission (NRC) and Electric Power Research Institute (EPRI) guidelines and applicable industry standards; it specifies the critical characteristics of the relays, provides the tests and analysis required to verify the critical characteristics, the acceptance criteria for the test results, performs source verification to quality P&B for its control of the critical characteristics, and provides documentation. The program provides reasonable assurance that the new MDR relays will perform their intended safety functions.

  11. Introduction of the commercial grade dedication into Nuclear Power Plant Krsko (NEK) procurement process

    International Nuclear Information System (INIS)

    Heruc, Z.; Gajsak, Z.; Nikpalj, R.

    1996-01-01

    NEK management has undertaken a set of actions to improve the ability to provide equipment, spare parts and material needed to support operation and maintenance of the Krsko plant. These actions are necessary due primarily to the fact that NEK is more and more confronted (increasing trend) with the issue that suppliers of safety-related equipment and spare parts have decided not to pursue the nuclear portion of their business, incl. specific QA systems and qualifications. The purchase orders imposing these requirements are no longer accepted. In order to continue to obtain the necessary materials at the required quality level, a 'Commercial Grade Item' (CGI) procurement and dedication program has been developed based on similar practices in USA. (author)

  12. Introduction of the commercial grade dedication into Nuclear Power Plant Krsko (NEK) procurement process

    International Nuclear Information System (INIS)

    Heruc, Z.; Gajsak, Z.; Nikpalj, R.

    1996-01-01

    NEK management has undertaken a set of actions to improve the ability to provide equipment, spare parts and material needed to support operation and maintenance of the Krsko plant. These actions are necessary due primarily to the fact that NEK is more and more confronted (increasing trend) with the issue that suppliers of safety-related equipment and spare parts have decided not to pursue the nuclear portion of their business, incl. specific QA systems and qualifications. The purchase orders imposing these requirements are no longer accepted. In order to continue to obtain the necessary materials at the required quality level, a 'Commercial Grade Item' (CGI) procurement and dedication program has been developed based on similar practices in the USA. (author)

  13. Analysis of nuclear grade uranium oxides by atomic absorption spectrometry with electrothermal atomization

    International Nuclear Information System (INIS)

    Batistoni, D.A.; Erlijman, L.H.; Pazos, A.L.

    1986-01-01

    The application of atomic absorption spectrometry for the determination of five trace impurities in nuclear grade uranium oxides is described. The elements were separated from the uranium matrix by extraction chromatography and determined in 5.5 M nitric acid by electrothermal atomization using pyrolytic graphite coated tubes. Two elements, cadmium and chromium, with different volatility characteristics were employed to investigate the operating conditions. Drying and ashing conditions were studied for both elements. Ramp and constant potential (step) heating modes have also been studied and compared. Good reproducibility and a longer life of graphite tubes were obtained with ramp atomization. Detection limits (in micrograms per gram of uranium) were: Cd 0.01; Cr 0.1; Cu 0.4; Mn 0.04 and Ni 0.2. (author) [es

  14. A discussion of possible mechanisms affecting fission product transport in irradiated and unirradiated nuclear grade graphite

    International Nuclear Information System (INIS)

    Firth, M.J.

    1977-09-01

    137 Cs, 85 Sr, and sup(110m)Ag adsorption experiments were conducted on three graphite powders with differing amounts of specific basal and edge surface areas. No direct proportionality was found between the specific amounts of the isotopes adsorbed and either of the surface characteristics. There appears to be some correlation with the specific basal surface area despite the fact that each isotope behaves differently. Factors that might influence the adsorption behaviour of Cs and Ag during reactor irradiation and heat treatment of nuclear grade graphites are discussed. These include the form of Cs with the graphite surface. A model based on Cs adsorption at vacancy clusters is used to analyse adsorption experiments. A possible explanation for the behaviour of Ag through the migration of graphite impurities from the bulk of the graphite to the pore surface is also discussed. (author)

  15. An investigation on high temperature fatigue properties of tempered nuclear-grade deposited weld metals

    Science.gov (United States)

    Cao, X. Y.; Zhu, P.; Yong, Q.; Liu, T. G.; Lu, Y. H.; Zhao, J. C.; Jiang, Y.; Shoji, T.

    2018-02-01

    Effect of tempering on low cycle fatigue (LCF) behaviors of nuclear-grade deposited weld metal was investigated, and The LCF tests were performed at 350 °C with strain amplitudes ranging from 0.2% to 0.6%. The results showed that at a low strain amplitude, deposited weld metal tempered for 1 h had a high fatigue resistance due to high yield strength, while at a high strain amplitude, the one tempered for 24 h had a superior fatigue resistance due to high ductility. Deposited weld metal tempered for 1 h exhibited cyclic hardening at the tested strain amplitudes. Deposited weld metal tempered for 24 h exhibited cyclic hardening at a low strain amplitude but cyclic softening at a high strain amplitude. Existence and decomposition of martensite-austenite (M-A) islands as well as dislocations activities contributed to fatigue property discrepancy among the two tempered deposited weld metal.

  16. Determination of trace metals in nuclear-grade uranium dioxide by X-ray fluorescence spectrometry

    International Nuclear Information System (INIS)

    Salvador, V.L.R.; Imakuma, K.

    1988-04-01

    A method is described for the simultaneous determination of low concentrations of Ca, Cr, Cu, Fe, Mn and Ni in nuclear-grade uranium dioxide by X-ray fluorescence spectrometry, without the use of chemical treatment. The lower limits of detection range from 2 μg g -1 for nickel and manganese to 5 μg g -1 for copper. Samples are prepared in the form of double-layer pellets with boric acid as a binding agent. Standards are prepared in a U 3 O 8 matrix, which is more chemically stable than UO 2 and has similar matrix behaviour. The correlation coefficients for calibration curves are better than 0.999. Erros range from 2.4 % for chromium to 6.8 % for nickel. (author) [pt

  17. Standard test methods for chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade boron carbide

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2004-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade boron carbide powder and pellets to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Total Carbon by Combustion and Gravimetry 7-17 Total Boron by Titrimetry 18-28 Isotopic Composition by Mass Spectrometry 29-38 Chloride and Fluoride Separation by Pyrohydrolysis 39-45 Chloride by Constant-Current Coulometry 46-54 Fluoride by Ion-Selective Electrode 55-63 Water by Constant-Voltage Coulometry 64-72 Impurities by Spectrochemical Analysis 73-81 Soluble Boron by Titrimetry 82-95 Soluble Carbon by a Manometric Measurement 96-105 Metallic Impurities by a Direct Reader Spectrometric Method 106-114

  18. Wear Behavior of Selected Nuclear Grade Graphites at Room Temperature in Ambient Air Environment

    International Nuclear Information System (INIS)

    Kim, Eung-Seon; Park, Kwang-Seok; Kim, Yong-Wan

    2008-01-01

    In a very high temperature reactor (VHTR), graphite will be used not only for as a moderator and reflector but also as a major structural component due to its excellent neutronic, thermal and mechanical properties. In the VHTR, wear of graphite components is inevitable due to a neutron irradiation-induced dimensional change, thermal gradient, relative motions of graphite components and a shock load such as an earthquake. Large wear particles accumulated at the bottom of a reactor can influence the cooling of the lower part and small wear particles accumulated on the primary circuit and heat exchanger tube can make it difficult to inspect the equipment, and also decrease the heat exchange rate. In the present work, preliminary wear tests were performed at room temperature in ambient air environment to understand the basic wear characteristics of selected nuclear grade graphites for the VHTR

  19. A model for predicting the lifetimes of Grade-2 titanium nuclear waste containers

    Energy Technology Data Exchange (ETDEWEB)

    Shoesmith, D W; Ikeda, B M; Bailey, M G; Quinn, M J; LeNeveu, D M [Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Labs.

    1995-08-01

    The development of a model to predict the lifetimes of Grade-2 titanium containers for nuclear fuel waste is described. This model assumes that the corrosion processes most likely to lead to container failure are crevice corrosion, hydrogen-induced cracking and general corrosion. Because of the expected evolution of waste vault conditions from initially warm (<{approx} 100 deg C) and oxidizing to eventually cool (<30 deg C) and non-oxiding, the period for which crevice corrosion can propagate will be limited by repassivation, and long container lifetimes will be achieved since the rate of general corrosion is extremely low. However, in the model presented, not only is it assumed that crevices will initiate rapidly on all containers, but also that the propagation of these crevices will continue indefinitely since conditions will remain sufficiently oxiding for repassivation to be avoided. The mathematical development of the model is described in detail. A simple ramped distribution is used to describe the failures due to the presence of initial defects. For crevice corrosion the propagation rates are assumed to be normally distributed and to be determined predominantly by temperature. The temperature dependence of the crevice propagation rate is determined from the calculated cooling profiles for the containers and an experimentally determined Arrhenius relationship for crevice propagation rates. The cooling profiles are approximated by double or single step functions, depending on the location of the container within the vault. The experimental data upon which this model is based is extensively reviewed. This review includes descriptions of the available data to describe and quantify the processes of general corrosion, crevice corrosion and hydrogen-induced cracking. For crevice corrosion and hydrogen-induced cracking the results of studies on both Grades-2 and -12 are presented. Also, the effects of impurities in the Grade-2 material are discussed.

  20. A model for predicting the lifetimes of Grade-2 titanium nuclear waste containers

    International Nuclear Information System (INIS)

    Shoesmith, D.W.; Ikeda, B.M.; Bailey, M.G.; Quinn, M.J.; LeNeveu, D.M.

    1995-08-01

    The development of a model to predict the lifetimes of Grade-2 titanium containers for nuclear fuel waste is described. This model assumes that the corrosion processes most likely to lead to container failure are crevice corrosion, hydrogen-induced cracking and general corrosion. Because of the expected evolution of waste vault conditions from initially warm (<∼ 100 deg C) and oxidizing to eventually cool (<30 deg C) and non-oxiding, the period for which crevice corrosion can propagate will be limited by repassivation, and long container lifetimes will be achieved since the rate of general corrosion is extremely low. However, in the model presented, not only is it assumed that crevices will initiate rapidly on all containers, but also that the propagation of these crevices will continue indefinitely since conditions will remain sufficiently oxiding for repassivation to be avoided. The mathematical development of the model is described in detail. A simple ramped distribution is used to describe the failures due to the presence of initial defects. For crevice corrosion the propagation rates are assumed to be normally distributed and to be determined predominantly by temperature. The temperature dependence of the crevice propagation rate is determined from the calculated cooling profiles for the containers and an experimentally determined Arrhenius relationship for crevice propagation rates. The cooling profiles are approximated by double or single step functions, depending on the location of the container within the vault. The experimental data upon which this model is based is extensively reviewed. This review includes descriptions of the available data to describe and quantify the processes of general corrosion, crevice corrosion and hydrogen-induced cracking. For crevice corrosion and hydrogen-induced cracking the results of studies on both Grades-2 and -12 are presented. Also, the effects of impurities in the Grade-2 material are discussed. Special attention is

  1. Establishment of quality system program for the manufacture of nuclear grade steels

    International Nuclear Information System (INIS)

    Saito, Toru

    1978-01-01

    Recently, the pressure vessels employed in the fields of nuclear power generation, petroleum refining, and chemical industry tend to be large size and high performance, therefore thick steel plates and forgings of high quality are demanded, and the establishment and maintenance of strict quality assurance system for material production are required. In Mizushima Works, Kawasaki Steel Corp., the installations for large forgings and thick plates were constructed from 1969 to 1976, and the researches on the development of production techniques were forwarded in parallel. A Quality System Certificate (Material) has been granted to Mizushima Works on March 11, 1977, by the American Society of Mechanical Engineers for the manufacture of steel plates and forgings of nuclear grade. The quality system manual as the basis of quality assurance activities, the organization for quality assurance, its responsibility and authority, the discrimination of materials, the control of manufacturing processes, the qualification of workers in charge of nondestructive test, welding, heat treatment and others, the management of tests and inspections, the management of products with faults and repairing measures, and internal supervisory system are explained. The wide use of computers is novel in the field of quality system program. (Kako, I.)

  2. Nuclear heat-load limits for above-grade storage of solid transuranium wastes

    International Nuclear Information System (INIS)

    Clontz, B.G.

    1978-06-01

    Nuclear safety and heat load limits were established for above-grade storage of transuranium (TRU) wastes. Nuclear safety limits were obtained from a study by J.L. Forstner and are summarized. Heat load limits are based on temperature calculations for TRU waste drums stored in concrete containers (hats), and results are summarized. Waste already in storage is within these limits. The limiting factors for individual drum heat load limits were (1) avoidance of temperatures in excess of 190 0 F (decomposition temperature of anion resin) when anion resin is present in a concrete hat, and (2) avoidance of temperatures in excess of 450 0 F (ignition temperature of paper) at any point inside a waste drum. The limiting factor for concrete had heat load limits was avoidance of temperatures in excess of 265 0 F (melt point of high density polyethylene) at the drum liners. A temperature profile for drums and hats filled to recommended limits is shown. Equations and assumptions used were conservative

  3. Standard test methods for chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade uranium dioxide powders and pellets

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1999-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade uranium dioxide powders and pellets to determine compliance with specifications. 1.2 This test method covers the determination of uranium and the oxygen to uranium atomic ratio in nuclear-grade uranium dioxide powder and pellets. 1.4 This test method covers the determination of chlorine and fluorine in nuclear-grade uranium dioxide. With a 1 to 10-g sample, concentrations of 5 to 200 g/g of chlorine and 1 to 200 μg/g of fluorine are determined without interference. 1.5 This test method covers the determination of moisture in uranium dioxide samples. Detection limits are as low as 10 μg. 1.6 This test method covers the determination of nitride nitrogen in uranium dioxide in the range from 10 to 250 μg. 1.7 This test method covers the spectrographic analysis of nuclear-grade UO2 for the 26 elements in the ranges indicated in Table 2. 1.8 For simultaneous determination of trace ele...

  4. Stereological estimation of nuclear volume in benign and malignant melanocytic lesions of the skin. Inter- and intraobserver variability of malignancy grading

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Ottosen, P D

    1991-01-01

    The volume-weighted, mean nuclear volume (nuclear vv) may be estimated without any assumptions regarding nuclear shape using modern stereological techniques. As a part of an investigation concerning the prospects of nuclear vv for classification and malignancy grading of cutaneous melanocytic tum...

  5. Performance evaluation of nuclear grade filters for the Trupact-I pressure equalization system

    International Nuclear Information System (INIS)

    Sandoval, R.P.; Joseph, B.J.

    1987-01-01

    The performance of high-efficiency-particulate-air and ultra-low- penetration-air filters subjected to extreme environments of temperature, shock, pressure, and particulate loading was evaluated in a test program at the Sandia National Laboratories. The test program was initiated to evaluate the feasibility of using commercially available nuclear-grade filters in the filtered pressure equalization system of a contact-handled transuranic waste transport system, called TRUPACT-I. The filtered pressure equalization system of TRUPACT-I assures containment of the activity within the limits permitted by federal regulations and simultaneously equalizes the pressure between the cavity of the packaging and the environment, and minimizes the buildup of radiolytically generated gases. The filters were exposed to temperatures, pressures and stresses that exceed expected environments in normal and accident conditions of transport. The performance of the test filters was determined by measuring and quantifying filter efficiency and the Darcy constant. In addition, the integrity of the filter housing was evaluated using non-destructive helium leak testing. The details of the test program and results obtained from the tests are presented in this paper

  6. The tensile deformation behavior of nuclear-grade isotropic graphite posterior to hydrostatic loading

    International Nuclear Information System (INIS)

    Yoda, S.; Eto, M.

    1983-01-01

    The effects of prehydrostatic loading on microstructural changes and tensile deformation behavior of nuclear-grade isotropic graphite have been examined. Scanning electron micrographs show that formation of microcracks associated with delamination between basal planes occurs under hydrostatic loading. Hydrostatic loading on specimens results in the decrease in tensile strength and increase in residual strain generated by the applied tensile stress at various levels, indicating that the graphite material is weakened by hydrostatic loading. A relationship between residual strain and applied tensile stress for graphite hydrostatically-loaded at several pressure levels can be approximately expressed as element of= (AP + B) sigmasup(n) over a wide range hydrostatic pressure, where element of, P and sigma denote residual strain, hydrostatic pressure and applied tensile stress, respectively; A, B and n are constant. The effects of prehydrostatic loading on the tensile stress-strain behavior of the graphite were examined in more detail. The ratio of stress after hydrostatic loading to that before hydrostatic loading on the stress-strain relationship remains almost unchanged irrespective of strain. (orig.)

  7. Availability analysis of safety grade multiple redundant controller used in advanced nuclear safety systems

    International Nuclear Information System (INIS)

    Son, Kwang Seop; Kim, Dong Hoon; Park, Gee Yong; Kang, Hyun Gook

    2018-01-01

    Highlights: •The multiple redundant controller, SPLC is configured as the combination of DMR and TMR architecture. •We construct the Markov model of SPLC using the concept of the system unavailability rate. •To satisfy the availability requirement of safety grade controller, the fault coverage factor (FCF) should be ≥0.8 and the MTTR of each module should be ≤100 h when FCF is 0.9. •The availability of SPLC is better than that of PLC having iTMR architecture however it is poorer than iTMR considering the off-line test and inspection on the assumption that MTTR of each module is ≤200 h. -- Abstract: We analyze the availability of the Safety Programmable Logic Controller (SPLC) having multiple redundant architectures. In the SPLC, input/output and processor module are configured as triple modular redundancy (TMR), and backplane bus, power and communication modules are configured as dual modular redundancy (DMR). The voting logics for redundant architectures are based on the forwarding error detection. It means that the receivers perform the voting logics based on the status information of transmitters. To analyze the availability of SPLC, we construct the Markov model and simplify the model adopting the system unavailability rate. The results show that the fault coverage factor should be ≥0.8 and Mean Time To Repair (MTTR) should be ≤100 h in order to satisfy the requirement that the availability of the safety grade PLC should be ≥0.995. Also we evaluate the availability of SPLC comparing to other PLCs such as simplex, processor DMR (pDMR) and independent TMR (iTMR) PLCs used in the existing nuclear safety systems. The availability of SPLC is higher than those of the simplex, pDMR but is lower than that of iTMR for one month which is the periodic off-line test and inspection. That’s why the number of redundant modules used in PLC is more dominant to increasing the availability than the number of fault masking methods such as voting logics used

  8. Acoustic emission during tensile deformation and fracture of nuclear grade AISI type 304 stainless steel specimens with notches

    International Nuclear Information System (INIS)

    Mukhopadhyay, C.K.; Jayakumar, T.; Baldev Raj

    1996-01-01

    Acoustic emission generated during tensile deformation and fracture of nuclear grade AISI type 304 stainless steel specimens with notches has been studied. The extent of acoustic activity generated depends on notch tip severity, notch tip blunting and tearing of the notches. The equation N=AK m applied to the acoustic emission data of the notched specimens has shown good correlation. Acoustic emission technique can be used to estimate the size of an unknown notch. (author)

  9. Investigating the effects of stress on the pore structures of nuclear grade graphites

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Joshua E.L., E-mail: joshua.taylor@postgrad.manchester.ac.uk; Hall, Graham N., E-mail: graham.n.hall@manchester.ac.uk; Mummery, Paul M., E-mail: paul.m.mummery@manchester.ac.uk

    2016-03-15

    Graphite is used as a moderating material and as a structural component in a number of current generation nuclear reactors. During reactor operation stresses develop in the graphite components, causing them to deform. It is important to understand how the microstructure of graphite affects the material's response to these stresses. A series of experiments were performed to investigate how the pore structures of Pile Grade A and Gilsocarbon graphites respond to loading stresses. A compression rig was used to simulate the build-up of operational stresses in graphite components, and a confocal laser microscope was used to study variation of a number of important pore properties. Values of elastic modulus and Poisson's ratio were calculated and compared to existing literature to confirm the validity of the experimental techniques. Mean pore areas were observed to decrease linearly with increasing applied load, mean pore eccentricity increased linearly, and a small amount of clockwise pore rotation was observed. The response to build-up of stresses was dependent on the orientation of the pores and basal planes and the shapes of the pores with respect to the loading axis. It was proposed that pore closure and pore reorientation were competing processes. Pore separation was quantified using ‘nearest neighbour’ and Voronoi techniques, and non-pore regions were found to shrink linearly with increasing applied load. - Highlights: • Effects of stress on pore structures of Gilsocarbon and PGA graphites were studied. • Application of a compressive load was used to generate stresses in graphite. • Inverse linear relationship between stress and pore area was observed. • Mean pore eccentricity increased, clockwise pore rotation observed. • Separation of pores quantified using Voronoi and ‘nearest-neighbour’ methods.

  10. Grading nuclear, cortical and posterior subcapsular cataracts using an objective scatter index measured with a double-pass system.

    Science.gov (United States)

    Vilaseca, Meritxell; Romero, Maria José; Arjona, Montserrat; Luque, Sergio Oscar; Ondategui, Juan Carlos; Salvador, Antoni; Güell, José L; Artal, Pablo; Pujol, Jaume

    2012-09-01

    To evaluate objectively intraocular scattering in eyes with nuclear, cortical and posterior subcapsular cataracts by means of an objective scatter index (OSI) obtained from double-pass images. To compare the results with those obtained using clinical conventional procedures. In this prospective, observational, cross-sectional, non-consecutive case series study, 188 eyes with cataracts of 136 patients were analysed (123 eyes had nuclear, 41 eyes had cortical and 24 eyes had posterior subcapsular cataracts). The control group consisted of 117 eyes of 68 healthy patients. Patient examination included subjective refraction, best spectacle-corrected visual acuity (BSCVA), cataract grade using the lens opacities classification system III (LOCS III) and OSI. We found a decrease in the BSCVA and an increase in the OSI with increasing cataract grade. Statistically significant differences were observed when the OSI of eyes without cataracts and those with different LOCS III were compared. The comparison between the OSI and LOCS III reported good percentages of agreement regarding the number of eyes classified in equivalent levels: 72.4% (nuclear cataracts), 86.6% (cortical cataracts) and 84.3% (posterior subcapsular cataracts). A non-linear regression model was applied between OSI and BSCVA, which resulted in the following multiple correlation coefficients: r=0.878 (nuclear), r=0.843 (cortical) and r=0.844 (posterior subcapsular). The results of the study showed that OSI is a useful parameter for evaluating large amounts of intraocular scattering that can be used, in combination with other conventional procedures, as a valuable tool in clinical practice to grade cataracts objectively.

  11. Radiotracers in performance evaluation of nuclear grade resins Amberlite IRN-78 and Purolite NRW-8000

    International Nuclear Information System (INIS)

    Singare, P.U.

    2014-01-01

    The present paper deals with evaluation of organic base nuclear grade anion exchange resins Amberlite IRN-78 and Purolite NRW-8000 by application of radioactive tracer isotopes 131 I and 82 Br. The evaluation was made on the basis of their performance in iodide and bromide ion-isotopic exchange reactions carried out under different experimental conditions like temperature and ionic concentration. It was observed that during iodide ion-isotopic exchange reaction at a constant temperature of 30.0 C, as the concentration of labeled iodide ion solution increases from 0.001 mol/L to 0.004 mol/L, the percentage of iodide ions exchanged increases from 70.10 % to 77.10 % for Amberlite IRN-78, which was higher than an increase of 63.90 % to 71.00 % as obtained for Purolite NRW-8000 resins. Also at a constant temperature of 30.0 C, using 1.000 g of ion exchange resins and 0.001 mol/L labeled iodide ion solution, the values of specific reaction rate (min -1 ), amount of iodide ion exchanged (mmol), initial rate of iodide ion exchange (mmol/min) and log K d were calculated to be 0.280, 0.175, 0.049 and 11.4 respectively for Amberlite IRN-78 resin, which was higher than the values of 0.258, 0.160, 0.041 and 10.6 respectively as that obtained by using Purolite NRW-8000 resins. The identical trend was observed for the two resins during bromide ion-isotopic exchange reaction. The results of present investigation also indicate that during the two ion-isotopic exchange reactions, for both the resins, there exists a strong positive linear correlation between amount of ions exchanged and concentration of ionic solution; and strong negative correlation between amount of ions exchanged and temperature of exchanging medium. The overall results indicate that under identical experimental conditions, Amberlite IRN-78 resins show superior performance over Purolite NRW-8000 resins. (orig.)

  12. Oxidation of PCEA nuclear graphite by low water concentrations in helium

    Energy Technology Data Exchange (ETDEWEB)

    Contescu, Cristian I., E-mail: ContescuCI@ornl.gov [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6087 (United States); Mee, Robert W. [Department of Business Analytics and Statistics, University of Tennessee, Knoxville, TN 37996-0525 (United States); Wang, Peng [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6087 (United States); Romanova, Anna V.; Burchell, Timothy D. [Department of Business Analytics and Statistics, University of Tennessee, Knoxville, TN 37996-0525 (United States)

    2014-10-15

    Accelerated oxidation tests were performed to determine kinetic parameters of the chronic oxidation reaction (i.e. slow, continuous, and persistent) of PCEA graphite in contact with helium coolant containing low moisture concentrations in high temperature gas-cooled reactors. To the authors’ knowledge such a study has not been done since the detailed analysis of reaction of H-451 graphite with steam (Velasquez, Hightower, Burnette, 1978). Since that H-451 graphite is now unavailable, it is urgently needed to characterize chronic oxidation behavior of new graphite grades that are being considered for use in gas-cooled reactors. The Langmuir–Hinshelwood mechanism of carbon oxidation by water results in a non-linear reaction rate expression, with at least six different parameters. They were determined in accelerated oxidation experiments that covered a large range of temperatures (800–1100 °C), and partial pressures of water (15–850 Pa) and hydrogen (30–150 Pa) and used graphite specimens thin enough (4 mm) in order to avoid diffusion effects. Data analysis employed a statistical method based on multiple likelihood estimation of parameters and simultaneous fitting of non-linear equations. The results show significant material-specific differences between graphite grades PCEA and H-451 which were attributed to microstructural dissimilarity between the two materials. It is concluded that kinetic data cannot be transferred from one graphite grade to another.

  13. Laboratory studies on the dissolution and solvent extraction of yellow cake to produce nuclear grade ammonium diuranate

    International Nuclear Information System (INIS)

    Bernido, C.C.; Pabelonia, C.A.; Balagtas, G.C.; Ubanan, E.

    1984-10-01

    Yellow cake or uranium concentrate, the semi-refined product from the processing of uranium-bearing ores in uranium mills has to undergo further processing and purification to nuclear grade specifications prior to conversion to uranium dioxide, the chemical form in which uranium is found in the fuel elements of many nuclear power reactor types, including the Philippines' PNPP-1. This paper presents the results of the studies conducted to obtain the optimum operating conditions for the first two steps in the processing of yellow cake to achieve nuclear grade purity, namely, (a) the dissolution of yellow cake in nitric acid, and (b) the separation of uranium from other impurities by solvent extraction using 20% Tri-butyl-Phosphate (TBP) in kerosene as the organic phase. The parameters studied for the dissolution step are acid molarity, temperature, and time; the optimum conditions obtained were: 4M HNO 3 , 100degC, and one hour, respectively. For the solvent extraction step, the following parameters were studied: aqueous to organic ratio, mixing time, and number of extraction stages; the optimum results obtained were O:A=4:1, three minutes mixing time, and three extraction stages, respectively. (author)

  14. Comparison of the oxidation rate and degree of graphitization of selected IG and NBG nuclear graphite grades

    Science.gov (United States)

    Chi, Se-Hwan; Kim, Gen-Chan

    2008-10-01

    The oxidation rate and degree of graphitization (DOG) were determined for some selected nuclear graphite grades (i.e., IG-110, IG-430, NBG-18, NBG-25) and compared in view of their filler coke type (i.e., pitch or petroleum coke) and the physical property of the grades. Oxidation rates were determined at six temperatures between 600 and 960 °C in air by using a three-zone vertical tube furnace at a 10 l/min air flow rate. The specimens were a cylinder with a 25.4 mm diameter and a 25.4 mm length. The DOG was determined based on the lattice parameter c determined from an X-ray diffraction (XRD). Results showed that, even though the four examined nuclear graphite grades showed a highly temperature-sensitive oxidation behavior through out the test temperature range of 600-950 °C, the differences between the grades were not significant. The oxidation rates determined for a 5-10% weight loss at the six temperatures were nearly the same except for 702 and 808 °C, where the pitch coke graphites showed an apparent decrease in their oxidation rate, more so than the petroleum coke graphites. These effects of the coke type reduced or nearly disappeared with an increasing temperature. The average activation energy determined for 608-808 °C was 161.5 ± 7.3 kJ/mol, showing that the dominant oxidation reaction occurred by a chemical control. A relationship between the oxidation rate and DOG was not observed.

  15. Comparison of the oxidation rate and degree of graphitization of selected IG and NBG nuclear graphite grades

    International Nuclear Information System (INIS)

    Chi, Se-Hwan; Kim, Gen-Chan

    2008-01-01

    The oxidation rate and degree of graphitization (DOG) were determined for some selected nuclear graphite grades (i.e., IG-110, IG-430, NBG-18, NBG-25) and compared in view of their filler coke type (i.e., pitch or petroleum coke) and the physical property of the grades. Oxidation rates were determined at six temperatures between 600 and 960 deg. C in air by using a three-zone vertical tube furnace at a 10 l/min air flow rate. The specimens were a cylinder with a 25.4 mm diameter and a 25.4 mm length. The DOG was determined based on the lattice parameter c determined from an X-ray diffraction (XRD). Results showed that, even though the four examined nuclear graphite grades showed a highly temperature-sensitive oxidation behavior through out the test temperature range of 600-950 deg. C, the differences between the grades were not significant. The oxidation rates determined for a 5-10% weight loss at the six temperatures were nearly the same except for 702 and 808 deg. C, where the pitch coke graphites showed an apparent decrease in their oxidation rate, more so than the petroleum coke graphites. These effects of the coke type reduced or nearly disappeared with an increasing temperature. The average activation energy determined for 608-808 deg. C was 161.5 ± 7.3 kJ/mol, showing that the dominant oxidation reaction occurred by a chemical control. A relationship between the oxidation rate and DOG was not observed

  16. Grading of Requirements for Radioactive Waste Activities in Nuclear Research Reactors: Radioisotope Production Facilities

    International Nuclear Information System (INIS)

    Tawfik, Y.E.

    2017-01-01

    A graded approach is applicable in all stages of the life time of a research reactor. During the life time of a research reactor, any grading performed should not, in any manner, affect safety functions and operational limits and conditions are preserved, so that there are no undue radiological hazards to workers, public or environment. The grading of activities should be based on safety analyses, and regulatory requirements. Other elements to be considered in grading are the complexity and the maturity of the technology, operating experience associated with the activities and the stage in the life time of the facility. In order to ensure that proper and a de quate provision is made for the safety implications associated with the management and disposal of radioactive waste, the waste is characterized and classified. The general scheme for classifying radioactive waste as presented in the current study is based on considerations of long term safety, and thus, by implication, disposal of the waste. This classification provides a starting point for the grading of activities associated with the packaging and disposal of radioactive waste

  17. Standard test methods for chemical and mass spectrometric analysis of nuclear-grade gadolinium oxide (Gd2O3) powder

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2006-01-01

    1.1 These test methods cover procedures for the chemical and mass spectrometric analysis of nuclear-grade gadolinium oxide powders to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Carbon by Direct CombustionThermal Conductivity C1408 Test Method for Carbon (Total) in Uranium Oxide Powders and Pellets By Direct Combustion-Infrared Detection Method Total Chlorine and Fluorine by Pyrohydrolysis Ion Selective Electrode C1502 Test Method for Determination of Total Chlorine and Fluorine in Uranium Dioxide and Gadolinium Oxide Loss of Weight on Ignition 7-13 Sulfur by CombustionIodometric Titration Impurity Elements by a Spark-Source Mass Spectrographic C761 Test Methods for Chemical, Mass Spectrometric, Spectrochemical,Nuclear, and Radiochemical Analysis of Uranium Hexafluoride C1287 Test Method for Determination of Impurities In Uranium Dioxide By Inductively Coupled Plasma Mass Spectrometry Gadolinium Content in Gadolinium Oxid...

  18. Determination of the impurities Al, Mn, Fe, Ni, Cu and Zn in nuclear grade uranium by ICP-OES

    Energy Technology Data Exchange (ETDEWEB)

    Kakazu, Mauricio H.; Cotrim, Marycel E.B.; Silva, Douglas B. da; Pires, Maria Aparecida F., E-mail: mhkakazu@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Uranium compounds are specially produced for use in nuclear reactors and must meet strict physical and chemicals specifications. The current study discusses the separation of Al, Mn, Fe, Ni, Cu and Zn from uranium compounds and their quantitative determination using inductively coupled plasma optical emission spectrometry. To avoid interference effect caused by uranium in the spectroscopic emission lines of elements of interest, the chromatographic behavior of TBP impregnated macroporous Amberlite XAD-4 column was investigated. The break through curves of uranium obtained showed maximum retention of up to 11 grams of uranium and the elution curves for the elements showed reproducible recovery rate of 90% on 50 mL elution. Synthetic samples of nuclear grade uranium prepared with the addition of 250 {mu}g/g of U of the above individual elements were used to verify the performance of the method. The method showed a recovery rate of 80 to 90% for the elements under study. (author)

  19. Determination of the impurities Al, Mn, Fe, Ni, Cu and Zn in nuclear grade uranium by ICP-OES

    International Nuclear Information System (INIS)

    Kakazu, Mauricio H.; Cotrim, Marycel E.B.; Silva, Douglas B. da; Pires, Maria Aparecida F.

    2011-01-01

    Uranium compounds are specially produced for use in nuclear reactors and must meet strict physical and chemicals specifications. The current study discusses the separation of Al, Mn, Fe, Ni, Cu and Zn from uranium compounds and their quantitative determination using inductively coupled plasma optical emission spectrometry. To avoid interference effect caused by uranium in the spectroscopic emission lines of elements of interest, the chromatographic behavior of TBP impregnated macroporous Amberlite XAD-4 column was investigated. The break through curves of uranium obtained showed maximum retention of up to 11 grams of uranium and the elution curves for the elements showed reproducible recovery rate of 90% on 50 mL elution. Synthetic samples of nuclear grade uranium prepared with the addition of 250 μg/g of U of the above individual elements were used to verify the performance of the method. The method showed a recovery rate of 80 to 90% for the elements under study. (author)

  20. Nondestructive Evaluation of Functionally Graded Subsurface Damage on Cylinders in Nuclear Installations Based on Circumferential SH Waves

    Directory of Open Access Journals (Sweden)

    Zhen Qu

    2016-01-01

    Full Text Available Subsurface damage could affect the service life of structures. In nuclear engineering, nondestructive evaluation and detection of the evaluation of the subsurface damage region are of great importance to ensure the safety of nuclear installations. In this paper, we propose the use of circumferential horizontal shear (SH waves to detect mechanical properties of subsurface regions of damage on cylindrical structures. The regions of surface damage are considered to be functionally graded material (FGM and the cylinder is considered to be a layered structure. The Bessel functions and the power series technique are employed to solve the governing equations. By analyzing the SH waves in the 12Cr-ODS ferritic steel cylinder, which is frequently applied in the nuclear installations, we discuss the relationship between the phase velocities of SH waves in the cylinder with subsurface layers of damage and the mechanical properties of the subsurface damaged regions. The results show that the subsurface damage could lead to decrease of the SH waves’ phase velocity. The gradient parameters, which represent the degree of subsurface damage, can be evaluated by the variation of the SH waves’ phase velocity. Research results of this study can provide theoretical guidance in nondestructive evaluation for use in the analysis of the reliability and durability of nuclear installations.

  1. Guideline on evaluation and acceptance of commercial grade digital equipment for nuclear safety applications

    International Nuclear Information System (INIS)

    1996-10-01

    Nuclear power plants are increasingly upgrading their instrumentation and control (I ampersand C) systems with commercial digital equipment, which allows them to continue meeting safety and reliability requirements while controlling operating costs. However, the use of commercial software-based devices for safety related applications has raised new issues that impact design, procurement, and licensing activities. This guideline describes a consistent, comprehensive approach for the evaluation and acceptance of commercial digital equipment for nuclear safety systems

  2. A Review Corrosion of TI Grade 7 and Other TI Alloys in Nuclear Waste Repository Environments

    Energy Technology Data Exchange (ETDEWEB)

    F. Hua; K. Mon; P. Pasupathi; G. Gordon

    2004-05-11

    Titanium alloy degradation modes are reviewed in relation to their performance in repository environments. General corrosion, localized corrosion, stress corrosion cracking, hydrogen induced cracking, microbially influenced corrosion, and radiation-assisted corrosion of Ti alloys are considered. With respect to the Ti Grade 7 drip shields selected for emplacement in the repository at Yucca Mountain, general corrosion, hydrogen induced cracking, and radiation-assisted corrosion will not lead to failure within the 10,000 year regulatory period; stress corrosion cracking (in the absence of disruptive events) is of no consequence to barrier performance; and localized corrosion and microbially influenced corrosion are not expected to occur. To facilitate the discussion, Ti Grades 2, 5, 7, 9, 11, 12, 16, 17, 18, and 24 are included in this review.

  3. A Review Corrosion of TI Grade 7 and Other TI Alloys in Nuclear Waste Repository Environments

    International Nuclear Information System (INIS)

    Hua, F.; Mon, K.; Pasupathi, P.; Gordon, G.

    2004-01-01

    Titanium alloy degradation modes are reviewed in relation to their performance in repository environments. General corrosion, localized corrosion, stress corrosion cracking, hydrogen induced cracking, microbially influenced corrosion, and radiation-assisted corrosion of Ti alloys are considered. With respect to the Ti Grade 7 drip shields selected for emplacement in the repository at Yucca Mountain, general corrosion, hydrogen induced cracking, and radiation-assisted corrosion will not lead to failure within the 10,000 year regulatory period; stress corrosion cracking (in the absence of disruptive events) is of no consequence to barrier performance; and localized corrosion and microbially influenced corrosion are not expected to occur. To facilitate the discussion, Ti Grades 2, 5, 7, 9, 11, 12, 16, 17, 18, and 24 are included in this review

  4. Quantitative Analysis of Lens Nuclear Density Using Optical Coherence Tomography (OCT with a Liquid Optics Interface: Correlation between OCT Images and LOCS III Grading

    Directory of Open Access Journals (Sweden)

    You Na Kim

    2016-01-01

    Full Text Available Purpose. To quantify whole lens and nuclear lens densities using anterior-segment optical coherence tomography (OCT with a liquid optics interface and evaluate their correlation with Lens Opacities Classification System III (LOCS III lens grading and corrected distance visual acuity (BCVA. Methods. OCT images of the whole lens and lens nucleus of eyes with age-related nuclear cataract were analyzed using ImageJ software. The lens grade and nuclear density were represented in pixel intensity units (PIU and correlations between PIU, BCVA, and LOCS III were assessed. Results. Forty-seven eyes were analyzed. The mean whole lens and lens nuclear densities were 26.99 ± 5.23 and 19.43 ± 6.15 PIU, respectively. A positive linear correlation was observed between lens opacities (R2 = 0.187, p<0.01 and nuclear density (R2 = 0.316, p<0.01 obtained from OCT images and LOCS III. Preoperative BCVA and LOCS III were also positively correlated (R2 = 0.454, p<0.01. Conclusions. Whole lens and lens nuclear densities obtained from OCT correlated with LOCS III. Nuclear density showed a higher positive correlation with LOCS III than whole lens density. OCT with a liquid optics interface is a potential quantitative method for lens grading and can aid in monitoring and managing age-related cataracts.

  5. Manufacturing of welded polyblock turbine rotors for pressurized water reactor nuclear plants; Optimization of the steel grade; Effect of impurities

    International Nuclear Information System (INIS)

    Pisseloup, J.; Poitrault, I.S.; De Badereau, A.; Bocquet, P.G.

    1986-01-01

    Le Creusot Heavy Forge has been manufacturing low-pressure (LP) disks and shaft ends for 1300-MW nuclear power plants. These forgings, in weldable 1.8Cr-1Ni-0.8Mo steel, are welded by Alsthom Atlantique. With the aim of improved quality, homogeneity of mechanical properties, hardenability, and weldability, this metallurgical research has been carried out: 1. Optimization of the steel grade (the effect of silicon, manganese, and molybdenum). 2. The influence of tempering and stress relief treatment parameters. 3. The effect of impurities. These studies have led the Steel Melting Shop of Creusot-Loire Factory to invest in a high-performance process of steelmaking: the heating ladle refining process. This new process has had spectacular results that have been confirmed by investigations on cut-up industrial forgings

  6. Standard test methods for chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade plutonium dioxide powders and pellets

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade plutonium dioxide powders and pellets to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Plutonium Sample Handling 8 to 10 Plutonium by Controlled-Potential Coulometry Plutonium by Ceric Sulfate Titration Plutonium by Amperometric Titration with Iron(II) Plutonium by Diode Array Spectrophotometry Nitrogen by Distillation Spectrophotometry Using Nessler Reagent 11 to 18 Carbon (Total) by Direct Combustion–Thermal Conductivity 19 to 30 Total Chlorine and Fluorine by Pyrohydrolysis 31 to 38 Sulfur by Distillation Spectrophotometry 39 to 47 Plutonium Isotopic Analysis by Mass Spectrometry Rare Earth Elements by Spectroscopy 48 to 55 Trace Elements by Carrier–Distillation Spectroscopy 56 to 63 Impurities by ICP-AES Impurity Elements by Spark-Source Mass Spectrography 64 to 70 Moisture by the Coulomet...

  7. Eddy current testing on structures of nuclear-grade IG-110 graphite for acceptance test in HTTR

    International Nuclear Information System (INIS)

    Ishihara, Masahiro; Saikusa, Akio; Iyoku, Tatsuo

    1993-09-01

    Core and core support graphite structures in the HTTR are mainly made of IG-110 graphite which is fine-grained isotropic and nuclear-grade. Nondestructive inspection with eddy current testing is planned to be applied to these graphite structures. Eddy current testing is widely applied to metallic structures and its testing method has been already established. On the other hand, the characteristics of graphite are quite different in micro-structure from these of metals. Therefore, the eddy current testing method provided for metallic structures can not be applied directly to graphite structures. Thus the eddy current testing method and condition were established for the graphite structures made of IG-110 graphite. (author)

  8. A microstructural comparison of two nuclear-grade martensitic steels using small-angle neutron scattering

    Science.gov (United States)

    Coppola, R.; Fiori, F.; Little, E. A.; Magnani, M.

    1997-06-01

    Results are presented of a small-angle neutron scattering (SANS) study on two 10-13% Cr martensitic stainless steels of interest for nuclear applications, viz. DIN 1.4914 (MANET specification, for fusion reactors) and AISI 410. The investigation has focussed principally on microstructural effects associated with the differences in chromium content between the two alloys. The size distribution functions determined from nuclear and magnetic SANS components for the two steels given identical heat treatments are in accord with an interpretation based on the presence of ˜ 1 nm size CCr aggregates in the microstructure. Much larger (˜ 10 nm) scattering inhomogeneities with different magnetic contrast are also present and tentatively identified as carbides.

  9. Investigations into the fatigue behaviour of nuclear grades of austenitic stainless steel

    International Nuclear Information System (INIS)

    Mann, J.

    2015-01-01

    Full text of publication follows. Fatigue is an important problem within the nuclear industry due to the complex combination of thermal and mechanical loading that components experience during the operation of a nuclear reactor. Austenitic stainless steels are widely used within nuclear reactors for a number of applications including piping systems and pressure vessels. A number of studies have shown that austenitic stainless steel components operating within a light water reactor (LWR) environment may experience a significant reduction in fatigue life under certain circumstances, however the precise mechanisms responsible for the reduction are still not fully understood. The effects of environment are included in some fatigue assessment methods, however these are generally considered to be over-conservative and predicted fatigue lifetimes are not reflected well by service experience. This project aims to enhance the understanding of fatigue in both air and LWR environments through the synergistic use of a wide range of different microscopy techniques. It is expected that a better understanding of each of the different stages of fatigue will lead to more accurate fatigue predictions that ultimately result in better and safer lifetime predictions. This paper focuses on introducing the background behind the project, highlighting the current methods for assessing fatigue lifetimes and the motivations for the current research. The results of various initial microscopic investigations are presented, with a focus on a number of novel applications using laser scanning confocal microscopy to perform large scale analyses of fatigue fracture surfaces and test specimen gauge length surfaces. The use of surface replicas in conjunction with laser scanning confocal microscopy is discussed along with its potential applications for the assessment of fatigue damage in in-service components. Initial finite element modelling of crack growth within fatigue test specimens is discussed

  10. Standard specification for nuclear-grade silver-indium-cadmium alloy

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2003-01-01

    1.1 This specification covers silver-indium-cadmium alloy for use as a control material in light-water nuclear reactors. 1.2 The scope of this specification excludes the use of this material in applications where material strength of this alloy is a prime requisite. Also, this material must be protected from the primary water by a corrosion and wear resistant cladding. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

  11. Chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade mixed oxides [(U,Pu)O2

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    Mixed oxide, a mixture of uranium and plutonium oxides, is used as a nuclear-reactor fuel in the form of pellets. The plutonium content may be up to 10 wt %, and the diluent uranium may be of any U-235 enrichment. In order to be suitable for use as a nuclear fuel, the material must meet certain criteria for combined uranium and plutonium content, effective fissile content, and impurity content. Analytical procedures used to determine if mixed oxides comply with specifications are: uranium by controlled-potential coulometry; plutonium by controlled-potential coulometry; plutonium by amperometric titration with iron (II); nitrogen by distillation spectrophotometry using Nessler reagent; carbon (total) by direct combustion-thermal-conductivity; total chlorine and fluorine by pyrohydrolysis; sulfur by distillation-spectrophotometry; moisture by the coulometric, electrolytic moisture analyzer; isotopic composition by mass spectrometry; rare earths by copper spark spectroscopy; trace impurities by carrier distillation spectroscopy; impurities by spark-source mass spectrography; total gas in reactor-grade mixed dioxide pellets; tungsten by dithiol-spectrophotometry; rare earth elements by spectroscopy; plutonium-238 isotopic abundance by alpha spectrometry; uranium and plutonium isotopic analysis by mass spectrometry; oxygen-to-metal atom ratio by gravimetry

  12. Standard test methods for chemical and spectrochemical analysis of nuclear-Grade silver-indium-cadmium alloys

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1990-01-01

    1.1 These test methods cover procedures for the chemical and spectrochemical analysis of nuclear grade silver-indium-cadmium (Ag-In-Cd) alloys to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Silver, Indium, and Cadmium by a Titration Method 7-15 Trace Impurities by Carrier-Distillation Spectro- chemical Method 16-22 1.3 The values stated in SI units are to be regarded as the standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard and precautionary statements, see Section 5 and Practices E50. 7.1 This test method is applicable to the determination of silver, indium, and cadmium in alloys of approximately 80 % silver, 15 % indium, and 5 % cadmium used in nuclear reactor control r...

  13. Reliability Analysis of Safety Grade PLC(POSAFE-Q) for Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kim, J. Y.; Lyou, J.; Lee, D. Y.; Choi, J. G.; Park, W. M.

    2006-01-01

    The Part Count Method of the military standard MILHDK- 217F has been used for the reliability prediction of the nuclear field. This handbook determines the Programmable Logic Controller (PLC) failure rate by summing the failure rates of the individual component included in the PLC. Normally it is easily predictable that the components added for the fault detection improve the reliability of the PLC. But the application of this handbook is estimated with poor reliability because of the increased component number for the fault detection. To compensate this discrepancy, the quantitative reliability analysis method is suggested using the functional separation model in this paper. And it is applied to the Reactor Protection System (RPS) being developed in Korea to identify any design weak points from a safety point of view

  14. Standard specification for uranium oxides with a 235U content of less than 5 % for dissolution prior to conversion to nuclear-grade uranium dioxide

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 This specification covers uranium oxides, including processed byproducts or scrap material (powder, pellets, or pieces), that are intended for dissolution into uranyl nitrate solution meeting the requirements of Specification C788 prior to conversion into nuclear grade UO2 powder with a 235U content of less than 5 %. This specification defines the impurity and uranium isotope limits for such urania powders that are to be dissolved prior to processing to nuclear grade UO2 as defined in Specification C753. 1.2 This specification provides the nuclear industry with a general standard for such uranium oxide powders. It recognizes the diversity of conversion processes and the processes to which such powders are subsequently to be subjected (for instance, by solvent extraction). It is therefore anticipated that it may be necessary to include supplementary specification limits by agreement between the buyer and seller. 1.3 The scope of this specification does not comprehensively cover all provisions for prevent...

  15. Final report on characterization of time dependent deformations in concrete grades used in nuclear power plants

    International Nuclear Information System (INIS)

    Ramaswamy, Ananth; Chandra Kishen, J.M.

    2009-09-01

    Time dependent deformations in concrete, both creep and shrinkage, play a critical role in prestressed concrete structures, such as bridge girders, nuclear containment vessels, etc. These strains result in losses, through release of prestress, and thereby influence the safety of these structures. The present study comprises of an experimental and analytical program to assess the levels of creep and shrinkage in normal and heavy density concrete. The experimental program includes tests on creep using standard cylinder specimen, while shrinkage studies have been conducted using prism specimen, both under controlled environmental conditions. The experimental results suggest that creep and shrinkage strains are higher in heavy density concrete than in normal concrete. This may be attributed to the relatively smaller pore structure of heavy density concrete that results in larger availability of free water and a relatively slower hydration process in comparison to normal concrete. While there is some scatter in the results, creep strains decrease with age of loading and both creep and shrinkage strains are smaller when the relative humidity is higher. Statistical model reported in the literature for normal concrete is able to predict the test results for both normal and heavy density concrete quite well. Long term predictions of creep and shrinkage using this model, accounting for uncertainties, is also projected and shown to predict some long term measured results not used in the model calibration. The long term predictions are sensitive to the initial data used in model calibration. (author)

  16. Regeneration of the iodine isotope-exchange efficiency for nuclear-grade activated carbons

    International Nuclear Information System (INIS)

    Deitz, V.R.

    1985-01-01

    The removal of radioactive iodine from air flows passing through impregnated activated carbons depends on a minimum of three distinguishable reactions: (1) adsorption on the carbon networks of the activated carbons, (2) iodine isotope exchange with impregnated iodine-127, and (3) chemical combination with impregnated tertiary amines when present. When a carbon is new, all three mechanisms are at peak performance and it is not possible to distinguish among the three reactions by a single measurement; the retention of methyl iodide-127 is usually equal to the retention of methyl iodide-131. After the carbon is placed in service, the three mechanisms of iodine removal are degraded by the contaminants of the air at different rates; the adsorption process degrades faster than the other two. This behavior will be shown by comparisons of methyl iodide-127 and methyl iodide-131 penetration tests. It was found possible to regenerate the iodine isotope-exchange efficiency by reaction with airborne chemical reducing agents with little or no improvement in methyl iodine-127 retention. Examples will be given of the chemical regeneration of carbons after exhaustion with known contaminants as well as for many carbons removed from nuclear power operations. The depth profile of methyl iodide-131 penetration was determined in 2-inch deep layers before and after chemical treatments

  17. Near term feasibility of nuclear reactor for sea-water desalting: coupling of standard condensing nuclear power stations to low grade heat multieffect distillation plants

    International Nuclear Information System (INIS)

    Adar, J.; Manor, S.; Schaal, M.

    1977-01-01

    Commercial nuclear power reactors exist only in standard sizes and designs. No large nuclear back-pressure turbines are available today. Therefore, near term large scale nuclear desalination plants must be tailored to the NSSS sizes and available turbines and not the contrary. Standard condensing nuclear turbines could operate continuously with a back-presure of up to 5-7'' Hg (depending on the supplier). It means that they can exhaust huge amounts of steam at 56 0 C - 64 0 C with a loss of electricity production of 6% - 10% when compared to 2 1/2'' Hg normal condensing pressure. The horizontal aluminium tube multi-effect distillation process developed by ''Israel Desalination Engineering'' Ltd. is very suitable for the use of such low-grade heat: 4 to 9 effects can operate within these temperature ranges. A special flash-chamber constitutes a positive barrier against any possible contamination being carried over by the steam exhausted from the turbine to the desalination plant. Flow sheets, heat and mass balances have been prepared for two standard sizes of NSSS and turbines (1882sup(Mwth) and 2785sup(Mwth)), two ''back-pressures'' (5 1/2'' and 7'' Hg), and corresponding desalination plants. Only standard equipment is being used in the steam and electricity producing plant. The desalination plant consists of 6 to 12 parallel double lines, each of them similar to a large prototype now being designed and which is going to be coupled to an old fossil power station. Water production varies between 50 and 123 sup(us MGD) and water cost between 23 and 36 sup(cents)/M 3 . Total energy requirements of the desalination plant represent only 19 to 50% of the total water cost as against 75% for a single purpose plant. Costs are based on actual bids for the power plant and actual estimates for the desalination prototype. The operation is designed to be flexible so that the power plant can be operated either in conjunction with the desalination plant, or as a single purpose

  18. Numerical simulation on flow field of nuclear safety grade 2 single-seat pneumatic diaphragm control valve

    International Nuclear Information System (INIS)

    Zhong Yun; Zhang Jige; Wang Dezhong; Shi Jianzhong

    2010-01-01

    The Computational Fluid Dynamics (CFD) method is employed to simulate numerically the steady flow and transient flow under variable openings of the nuclear safety grade 2 single-seat pneumatic diaphragm control valve, which is a sleeve valve. The steady simulations under rated condition tells that there is a large amount of vortex in the valve seat necking and around the valve cone, which leads to a much greater flow impact on the head of the valve cone and uneven pressure distribution on spool face. More consideration should be taken on the characteristics of the valve cone accordingly, when designing a valve of this kind. Then the transient flow under 100% and 40% openings is simulated numerically on the basis of steady simulations. The pulsation of the pressure magnitude at the points with large vorticity, in the valve seat necking and around the valve cone, is monitored. The main pulsation frequencies differ from the low natural frequencies of the model, which means that it is safe from leading to structural resonance. (authors)

  19. Crevice corrosion and hydrogen embrittlement of grades-2 and -12 titanium under Canadian nuclear waste vault conditions

    International Nuclear Information System (INIS)

    Ikeda, B.M.; Bailey, M.G.; Clarke, C.F.; Shoesmith, D.W.

    1990-01-01

    Results on the corrosion of titanium grades 2 and 12 under the saline conditions anticipated in Canadian nuclear waste vaults are presented. The experimental approach included short-term electrochemical experiments to determine corrosion mechanisms, the susceptibility of titanium to crevice corrosion under a variety of conditions, and the extent of hydrogen uptake under controlled conditions; medium-term corrosion tests lasting a few weeks to a few months; and long-term immersion tests to provide rates for uniform corrosion, crevice corrosion, and hydrogen pickup. Results indicated that propagation, not initiation, is important in establishing susceptibility to crevice corrosion. Increasing the iron content of Ti-2 to 0.13 weight percent prevents crevice corrosion by causing repassivation. Crevice corrosion initiates on Ti-12, but repassivation is rapid. The supply of oxidant is essential to maintain crevice propagation. Hydrogen embrittlement is unlikely unless oxide film breakdown occurs. Film breakdown occurs under crevice conditions, and hydrogen pickup is to be expected. Film breakdown could occur if the strain or creep rate is fast enough to compete with repassivation reactions, a highly unlikely situation

  20. Standard test method for determination of impurities in nuclear grade uranium compounds by inductively coupled plasma mass spectrometry

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This test method covers the determination of 67 elements in uranium dioxide samples and nuclear grade uranium compounds and solutions without matrix separation by inductively coupled plasma mass spectrometry (ICP-MS). The elements are listed in Table 1. These elements can also be determined in uranyl nitrate hexahydrate (UNH), uranium hexafluoride (UF6), triuranium octoxide (U3O8) and uranium trioxide (UO3) if these compounds are treated and converted to the same uranium concentration solution. 1.2 The elements boron, sodium, silicon, phosphorus, potassium, calcium and iron can be determined using different techniques. The analyst's instrumentation will determine which procedure is chosen for the analysis. 1.3 The test method for technetium-99 is given in Annex A1. 1.4 The values stated in SI units are to be regarded as standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish ...

  1. Near-term feasibility of nuclear reactors for seawater desalting. Coupling of standard condensing nuclear power stations to low-grade heat multieffect distillation plants

    International Nuclear Information System (INIS)

    Adar, J.; Manor, S.; Schaal, M.

    1977-01-01

    The paper describes the horizontal aluminium tube, multieffect distillation process developed by Israel Desalination Engineering Ltd., which is very suitable for the use of low-grade heat from standard condensing nuclear turbines operating at increased back-pressure. A special flash-chamber constitutes a positive barrier against any possible contamination being carried over by the steam exhausted from the turbine to the desalination plant. Flow sheets, heat and mass balances have been prepared for two standard sizes of NSSS and turbines, two back-pressures, and corresponding desalination plants. Only standard equipment is being used in the steam and electricity-producing plant. The desalination plant consists of 6 to 12 parallel double lines, each of them similar to a large prototype now being designed and which will be coupled to an old fossil-fuel power station. Total energy requirements of the desalination plant represent only 19 to 50% of the total water cost as against 75% for a single-purpose plant. Costs are based on actual bids for the power plant and actual estimates for the desalination prototype. The operation is designed to be flexible so that the power plant can be operated either in conjunction with the desalination plant, or as a single-purpose plant. (author)

  2. Development of a graded approach to natural phenomena hazard design and evaluation of radioactive waste and spent fuel stored at nuclear power plants

    International Nuclear Information System (INIS)

    Stevenson, J.D.

    2001-01-01

    Nuclear safety related structures, systems and components, SSC, at large commercial nuclear power plants other than those applicable to reactor safety have in general not received the attention and detailed loading and behavior criteria use for reactor design safety. Such systems include spent fuel storage and radioactive waste storage and processing. In this paper is a suggested grading of design bases for natural hazards to be applied to such facilities commensurate with their radioactive risk. They are applicable to the full range of safety related SSC which are determined by the inventory of radioactive isotopes and the unmitigated doses at appropriate plant and site boundaries. (author)

  3. Review of experience gained in fabricating nuclear grade uranium and thorium compounds and their analytical quality control at the Instituto de Energia Atomica, Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Abrao, A.; Franca Junior, J.M.; Ikuta, A.

    1977-01-01

    The main activities developed at 'Instituto de Energia Atomica' Sao Paulo, Brazil, on the recovery of uranium from ores, the purification of uranium and thorium raw concentrates and their transformation in nuclear grade compounds, are reviewed. The design and assemble of pilot facilities for ammonium diuranate (ADV) uranium tetrafluoride, uranium trioxide, uranium oxide microspheres, uranyl nitrate denitration, uranim hexafluoride and thorium compounds are discussed. The establishment of analytical procedures are emphasized [pt

  4. Radiotracer application for characterization of nuclear grade anion exchange resins Tulsion A-23 and Dowex SBR LC

    International Nuclear Information System (INIS)

    Singare, P.U.

    2015-01-01

    Radio isotopic tracer technique as one of the versatile nondestructive technique is employed to evaluate the performance of nuclear grade anion exchange resins Tulsion A-23 and Dowex SBR LC. The evaluation was made on the basis of ion-isotopic exchange reaction kinetics by using 131 I and 82 Br radioactive tracer isotopes. It was observed that for both the resins, the values of specific reaction rate (min -1 ), amount of ion exchanged (mmol) and initial rate of ion exchange (mmol/min) were calculated to be lower for bromide ion-isotopic exchange reaction than that for iodide ion-isotopic exchange reaction. It was observed that for iodide ion-isotopic exchange reaction under identical experimental conditions of 30.0 C, 1.000 g of ion exchange resins and 0.001 mol/L labeled iodide ion solution, the values of specific reaction rate (min -1 ), amount of iodide ion exchanged (mmol), initial rate of iodide ion exchange (mmol/min) and log K d were calculated as 0.377, 0.212, 0.080 and 15.5 respectively for Dowex SBR LC resin, which was higher than 0.215, 0.144, 0.031 and 14.1 respectively as that obtained for Tulsion A23 resins. Also at a constant temperature of 30.0 C, as the concentration of labeled iodide ion solution increases from 0.001 mol/L to 0.004 mol/L, the percentage of iodide ions exchanged increases from 84.75 % to 90.20 % for Dowex SBR LC resins which was higher than increases from 57.66 % to 62.38 % obtained for Tulsion A23 resins. The identical trend was observed for the two resins during bromide ion-isotopic exchange reaction. The overall results indicate superior performance of Dowex SBR LC over Tulsion A23 resins under identical experimental conditions.

  5. Cytological study of DNA content and nuclear morphometric analysis for aid in the diagnosis of high-grade dysplasia within oral leukoplakia.

    Science.gov (United States)

    Yang, Xi; Xiao, Xuan; Wu, Wenyan; Shen, Xuemin; Zhou, Zengtong; Liu, Wei; Shi, Linjun

    2017-09-01

    To quantitatively examine the DNA content and nuclear morphometric status of oral leukoplakia (OL) and investigate its association with the degree of dysplasia in a cytologic study. Oral cytobrush biopsy was carried out to obtain exfoliative epithelial cells from lesions before scalpel biopsy at the same location in a blinded series of 70 patients with OL. Analysis of nuclear morphometry and DNA content status using image cytometry was performed with oral smears stained with the Feulgen-thionin method. Nuclear morphometric analysis revealed significant differences in DNA content amount, DNA index, nuclear area, nuclear radius, nuclear intensity, sphericity, entropy, and fractal dimension (all P content analysis identified 34 patients with OL (48.6%) with DNA content abnormality. Nonhomogeneous lesion (P = .018) and high-grade dysplasia (P = .008) were significantly associated with abnormal DNA content. Importantly, the positive correlation between the degree of oral dysplasia and DNA content status was significant (P = .004, correlation coefficient = 0.342). Cytology analysis of DNA content and nuclear morphometric status using image cytometry may support their use as a screening and monitoring tool for OL progression. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Study of the behavior to corrosion of samples of nuclear grade aluminium sheathed in nickel-phosphorous alloys obtained autocatalytically

    International Nuclear Information System (INIS)

    Castro, Maria Eugenia; Barbero, Jose Alfredo; Bubach, Ernesto

    2006-01-01

    One of the ways to protect an industrially important metallic material against corrosion is by covering the piece with an approximately 1 μm layer of a material whose resistance to corrosion is greater than the element being protected. The mechanism by which the anticorrosive protection is obtained is with the formation of a pore free physical barrier without defects that impedes the arrival of the agents responsible for the electrochemical attack. Other sacrifice anodes such as aluminum or zinc have protective forms based on their dissolution as a consequence of their less electrochemically noble behavior to preserve the material. This work studies the resistance to the corrosion of metallic coatings on nuclear grade aluminum substrates. The focus is on coating nickel-phosphorous (ni-P) alloys obtained autocatalytically from aluminum 6061. A comparative study is carried out of a series of electroless nickel coatings containing different amounts of the latter element, but without surpassing the threshold of 12%. The work includes the study of another nickel coating, Vitrovac 0080 (without phosphorous content) in order to compare structures and anticorrosive properties. These materials are also compared with the Al6061 substrate without any kind of coating. The study is carried out with surface characterization of each one of the samples with or without coating using a series of complementary techniques, such as chemical and electrochemical techniques (linear-sweep voltammetry, cyclic voltammetry, determination of the polarization resistance) and physical techniques (SEM microscopy, determination of micro-hardness). The correlation of variables is carried out later as a function of the phosphorous content of the test samples. The structures obtained from the coatings are amorphous. They have no pores or faults and have high hardness values. The electrochemical study proves that the anticorrosive protection capacity of the Ni-P alloy increases along with the

  7. Standard test methods for chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade mixed oxides ((U, Pu)O2)

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade mixed oxides, (U, Pu)O2, powders and pellets to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Uranium in the Presence of Pu by Potentiometric Titration Plutonium by Controlled-Potential Coulometry Plutonium by Amperometric Titration with Iron (II) Nitrogen by Distillation Spectrophotometry Using Nessler Reagent 7 to 14 Carbon (Total) by Direct Combustion-Thermal Conductivity 15 to 26 Total Chlorine and Fluorine by Pyrohydrolysis 27 to 34 Sulfur by Distillation-Spectrophotometry 35 to 43 Moisture by the Coulometric, Electrolytic Moisture Analyzer 44 to 51 Isotopic Composition by Mass Spectrometry Rare Earths by Copper Spark Spectroscopy 52 to 59 Trace Impurities by Carrier Distillation Spectroscopy 60 to 69 Impurities by Spark-Source Mass Spectrography 70 to 76 Total Gas in Reactor-Grade Mixed Dioxide P...

  8. Measurements of Chlorine by XPS and SIMS in Nuclear-Grade Graphite. Effect of Treatment by UV, Heat and Moisture

    International Nuclear Information System (INIS)

    Grossiord, C.; Amalric, J.; Rahmani, L.

    2016-01-01

    Pieces of historical nuclear-grade graphite from the same block were submitted to a treatment involving soft or hard UV and heating in moist air. XPS investigations before treatment have shown that – at the geometric surface at least – chlorine binds more commonly by covalent (30 to 100% depending on spots) than ionic bonds. After treatment, bond types are more balanced, though hardly more uniform. Shifts of the ionic peak indicating an oxidised bond were not found. Surface chlorine was measured up to 0.04% atomic. Treatment by hard UV and heating in moist air for 1 ½ hours up to 122°C led to a decrease of surface chlorine by a factor of 2 as measured by ToF and XPS, helped by an etching technique that ensured the accurate positioning of the spots under analysis. Treatment for 8 hours up to 151°C resulted in a decrease of the ToF Cl/ 13 C signal for surface chlorine from 0.73 to 0.20 and of the atomic fraction from 0.02% to 0% as measured by XPS. SIMS investigations reveal that in the first 6 μm from the geometric surface, chlorine, hydrogen and oxygen have a decreasing profile suggestive of diffusion from the surface. In the vicinity to the surface the amounts of all three elements are much greater than in the bulk, possibly due to the availability of dangling bonds. It is speculated that when these are not saturated, back diffusion from the bulk under treatment may increase the quantity of surface chlorine. Treatment in moist air by hard UV for to 1 ½ hours has no marked effect on chlorine in the bulk, although it alters the quantities of hydrogen and oxygen. Treatment for 8 hours decreases chlorine by a factor of about 5 throughout the analysed depth of 6 μm and possibly farther to 15 μm, suggesting its diffusivity to be at least an order greater than 3.10 -16m 2 /s and possibly than 2.10 -15 m²/s, although a range of values is expected owing to the diverse tortuosity and constrictivity of pores. Ratios of hydrogen to oxygen and of chlorine to

  9. Study of the experimental parameters for the determination of Ca, Cr, Cu, Fe, Mn and Ni on nuclear grade UO2 by X-ray fluorescence technique

    International Nuclear Information System (INIS)

    Salvador, V.L.R.

    1982-01-01

    An analytical method for the simultaneous determinations of low concentrations of Ca, Cr, Cu, Fe, Mn and Ni on the nuclear grade UO 2 by X-ray fluorescence technique, without the use of chemical treatment, is described. The optimization of the experimental conditions was established on the X-ray fluorescence spectrometer and a low limit of detection (4 - 7 μg/gU) was achieved which satisfies the requirement in the nuclear fuel specification. The samples were prepared in the form of double layer pressed pellets using boric acid as a binding agent. The characteristic first order K sub(α) line intensity of each minor component was measured and the values of its concentrations were deduced using respective standard calibrations curves. The precision, accuracy and acceptability of the method were determined for all elements. The values of the precision are in the range of 2 - 10% and the accuracy are lower than 7%. (Author) [pt

  10. Standard test method for the determination of uranium by ignition and the oxygen to uranium (O/U) atomic ratio of nuclear grade uranium dioxide powders and pellets

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2000-01-01

    1.1 This test method covers the determination of uranium and the oxygen to uranium atomic ratio in nuclear grade uranium dioxide powder and pellets. 1.2 This test method does not include provisions for preventing criticality accidents or requirements for health and safety. Observance of this test method does not relieve the user of the obligation to be aware of and conform to all international, national, or federal, state and local regulations pertaining to possessing, shipping, processing, or using source or special nuclear material. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 1.4 This test method also is applicable to UO3 and U3O8 powder.

  11. Development of graded Ni-YSZ composite coating on Alloy 690 by Pulsed Laser Deposition technique to reduce hazardous metallic nuclear waste inventory.

    Science.gov (United States)

    Sengupta, Pranesh; Rogalla, Detlef; Becker, Hans Werner; Dey, Gautam Kumar; Chakraborty, Sumit

    2011-08-15

    Alloy 690 based 'nuclear waste vitrification furnace' components degrade prematurely due to molten glass-alloy interactions at high temperatures and thereby increase the volume of metallic nuclear waste. In order to reduce the waste inventory, compositionally graded Ni-YSZ (Y(2)O(3) stabilized ZrO(2)) composite coating has been developed on Alloy 690 using Pulsed Laser Deposition technique. Five different thin-films starting with Ni80YSZ20 (Ni 80 wt%+YSZ 20 wt%), through Ni60YSZ40 (Ni 60 wt%+YSZ 40 wt%), Ni40YSZ60 (Ni 40 wt%+YSZ 60 wt%), Ni20YSZ80 (Ni 20 wt%+YSZ 80 wt%) and Ni0YSZ100 (Ni 0 wt%+YSZ 100 wt%), were deposited successively on Alloy 690 coupons. Detailed analyses of the thin-films identify them as homogeneous, uniform, pore free and crystalline in nature. A comparative study of coated and uncoated Alloy 690 coupons, exposed to sodium borosilicate melt at 1000°C for 1-6h suggests that the graded composite coating could substantially reduced the chemical interactions between Alloy 690 and borosilicate melt. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Review of experience gained in fabricating nuclear grade uranium and thorium compounds and their analytical quality control at the Instituto de Energia Atomica, Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Abrao, A.; Franca, J.M. Jr.; Ikuta, A.; Pueschel, C.R.; Federgruen, L.; Lordello, A.R.; Tomida, E.K.; Moraes, S.; Brito, J. de; Gomes, R.P.; Araujo, J.A.; Floh, B.; Matsuda, H.T.

    1977-01-01

    This paper summarizes the main activities dealing with the fabrication of nuclear grade uranium and thorium compounds at the Instituto de Energia Atomica, Sao Paulo. Identification of problems and their resolutions, the experience gained in plant operation, the performance characteristics of an ion-exchange facility and a solvent extraction unit (a demonstration plant based on pulsed columns for purification of uranium and production of ammonium diuranate) are described. A moving-bed facility for UF 4 preparation and its operation is discussed. A pilot plant for uranium and thorium oxide microsphere preparation based on internal gelation for HTGR fuel type is also described. A solvent extraction pilot plant for thorium purification based on a compound extraction-scrubbing column and a mixer-settler battery and the involved technology for thorium purification are commented. The main products, namely ammonium diuranate, uranyl amonium tricarbonate, uranium trioxide, uranium tetrafluoride, thorium nitrate and thorium oxalate and their quality are commented. The development of necessary analytical procedures for the quality control of the mentioned nuclear grade products is summarized. A great majority of such procedures was particularly suitable for analyzing traces impurities. Designed for installation are the units for denitration of uranyl nitrate solutions and pilot plants for elemental fluorine and UF 6 . The installation of a laboratory-scale plant designed for reprocessing irradiated uranium and an experimental unit for the recovery of protactinium from irradiated thorium is in progress

  13. Development of Real Time Operating System for Safety Grade PLC (POSAFE-Q) for Nuclear Power Plants

    International Nuclear Information System (INIS)

    Son, Han Seong; Hwang, Sung Jae; Lee, Young Joon; Kim, Chang Hwoi; Lee, Dong Young

    2006-01-01

    POSAFE-Q is a newly developed programmable logic controller (PLC) in order to apply to digital safety system of nuclear power plants (NPP) according to Nuclear Power Plant safety requirements. POSAFE-Q hardware and software development process, including design, review, verification and validation, and configuration control and quality assurance, satisfies the requirements imposed by 10CFR50, Appendix B. This article introduces a real time operating system pCOS, which is the core of POSAFE-Q. Section 2 describes the structure of pCOS. Section 3 describes a few important features of pCOS, which are necessary to the application for the digital safety system of NPP

  14. Solubilization of industrial grade plant protein by enzymatic hydrolysis monitored by vibrational and nuclear magnetic resonance spectroscopy

    DEFF Research Database (Denmark)

    Bevilacqua, Marta; Pratico, Giulia; Plesner, Johanne

    2017-01-01

    Protein hydrolysates are of great interest in the food industry due to their nutritional and functional properties, but their use often implies solubilization in water and therefore hamper the use of plant proteins with inherent low water solubility. Protein solubility in water can be modified...... (1H NMR and IR) coupled with chemometrics analysis in monitoring the hydrolysis of five different industrial grade plant proteins by the enzyme Alcalase. Logarithmic modeling of the PCA (Principal Component Analysis) scores confirmed that they can represent a measurement of the solubilized protein...

  15. Separation of Cu, In, Fe and Sn from nuclear grade thorium by tri-n-octyl amine-5 M HCI and their determination by atomic absorption spectrophotometry

    International Nuclear Information System (INIS)

    Moraes, S. de; Cipriani, M.; Abrao, A.

    1976-01-01

    The results of solvent extraction separation of a group of metal traces in high pure thorium with the aid of tri-n-octyl amine-benzene from ThCL 4 HCI are summarized. ThCl 4 HCI-KI solutions Cu,In,Fe and Sn are extracted together and determined by atomic absoprtion spectrophotometry, burning directly the organic phase. The behavior of Cu,In,Fe and Sn toward direct burn of the organic phase using hydrogen-air mixture was studied, and an absorption enhancement was observed. The procedure is being used ot perform the quality control of nuclear grade thorium and its compounds. The calibration curves have provided precisions in the range 1 to 10% in analysis of thorium

  16. Separation of Cu, In, Fe and Sn from nuclear grade thorium by tri-n-octyl amine--5 M HCI and their determination by atomic absorption spectrophotometry

    Energy Technology Data Exchange (ETDEWEB)

    de Moraes, S; Cipriani, M; Abrao, A

    1976-03-01

    The results of solvent extraction separation of a group of metal traces in high pure thorium with the aid of tri-n-octyl amine-benzene from ThCl/sub 4/HCl are summarized. ThCl/sub 4/HCl-KI solutions of Cu, In, Fe and Sn are extracted together and determined by atomic absoprtion spectrophotometry and burning directly the organic phase. The behavior of Cu, In, Fe and Sn toward direct burn of the organic phase using hydrogen-air mixture was studied, and an absorption enhancement was observed. The procedure is being used to perform the quality control of nuclear grade thorium and its compounds. The calibration curves have provided precisions in the range 1 to 10% in analysis of thorium.

  17. Development of Real Time Operating System for Safety Grade PLC (POSAFE-Q) for Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Son, Han Seong [ENESYS, Taejon (Korea, Republic of); Hwang, Sung Jae [POSCON, Seoul (Korea, Republic of); Lee, Young Joon; Kim, Chang Hwoi; Lee, Dong Young [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2006-07-01

    POSAFE-Q is a newly developed programmable logic controller (PLC) in order to apply to digital safety system of nuclear power plants (NPP) according to Nuclear Power Plant safety requirements. POSAFE-Q hardware and software development process, including design, review, verification and validation, and configuration control and quality assurance, satisfies the requirements imposed by 10CFR50, Appendix B. This article introduces a real time operating system pCOS, which is the core of POSAFE-Q. Section 2 describes the structure of pCOS. Section 3 describes a few important features of pCOS, which are necessary to the application for the digital safety system of NPP.0.

  18. Evaluation of the effect of media velocity on filter efficiency and most penetrating particle size of nuclear grade high-efficiency particulate air filters.

    Science.gov (United States)

    Alderman, Steven L; Parsons, Michael S; Hogancamp, Kristina U; Waggoner, Charles A

    2008-11-01

    High-efficiency particulate air (HEPA) filters are widely used to control particulate matter emissions from processes that involve management or treatment of radioactive materials. Section FC of the American Society of Mechanical Engineers AG-1 Code on Nuclear Air and Gas Treatment currently restricts media velocity to a maximum of 2.5 cm/sec in any application where this standard is invoked. There is some desire to eliminate or increase this media velocity limit. A concern is that increasing media velocity will result in higher emissions of ultrafine particles; thus, it is unlikely that higher media velocities will be allowed without data to demonstrate the effect of media velocity on removal of ultrafine particles. In this study, the performance of nuclear grade HEPA filters, with respect to filter efficiency and most penetrating particle size, was evaluated as a function of media velocity. Deep-pleat nuclear grade HEPA filters (31 cm x 31 cm x 29 cm) were evaluated at media velocities ranging from 2.0 to 4.5 cm/sec using a potassium chloride aerosol challenge having a particle size distribution centered near the HEPA filter most penetrating particle size. Filters were challenged under two distinct mass loading rate regimes through the use of or exclusion of a 3 microm aerodynamic diameter cut point cyclone. Filter efficiency and most penetrating particle size measurements were made throughout the duration of filter testing. Filter efficiency measured at the onset of aerosol challenge was noted to decrease with increasing media velocity, with values ranging from 99.999 to 99.977%. The filter most penetrating particle size recorded at the onset of testing was noted to decrease slightly as media velocity was increased and was typically in the range of 110-130 nm. Although additional testing is needed, these findings indicate that filters operating at media velocities up to 4.5 cm/sec will meet or exceed current filter efficiency requirements. Additionally

  19. Effects of the Air Flow Rate on The Oxidation of NBG-18 and 25 Nuclear Graphite Grades

    International Nuclear Information System (INIS)

    Chi, Se-Hwan; Kim, Gen-Chan; Jang, Joon-Hee

    2007-01-01

    For a VHTR, graphite oxidation is regarded as a critical phenomenon for degrading the integrity of graphite components under normal or abnormal conditions. The oxidation of a graphite core component can occur by air which may permeate into the primary coolant operation and/or by impurities contained in the He coolant, or by air ingress during a severe accident. It is well known that the oxidation properties of a graphite are highly dependent on the source of raw materials, impurities, microstructures (crystallites, pore structure), and on the processing and environmental parameters, such as the forming methods, the coolant type, moisture and impurity content, temperature, flow rate and the oxygen potential of the coolants. A lot of work has been performed on the oxidation of graphite since the 1960s, and, for example, in the case of the temperature, a widely accepted oxidation model on the effects of a temperature has already been developed. However, in the case of the flow rate, even for its expected effects in a VHTR, for example, as to the expected changes in the bypass flow (10-20 %) during an operation, no systematic works have been performed. In this respect, as a preliminary study, the effects of an air flow rate on the oxidation of NBG-18 and 25 nuclear graphite were investigated

  20. Testing of nuclear grade lubricants and their effects on A540 B24 and A193 B7 bolting materials

    International Nuclear Information System (INIS)

    Czajkowski, C.J.

    1985-01-01

    An investigation was performed on eleven commonly used lubricants by the nuclear power industry. The investigation included EDS analysis of the lubricants, notched-tensile constant extension rate testing of bolting materials with the lubricants, frictional testing of the lubricants and weight loss testing of a bonded solid film lubricant. The report generally concludes that there is a significant amount of variance in the mechanical properties of common bolting materials; that MoS 2 can hydrolyze to form H 2 S at 100 0 C and cause stress corrosion cracking (SCC) of bolting materials, and that the use of copper-containing lubricants can be potentially detrimental to high strength steels in an aqueous environment. Additionally, the testing of various lubricants disclosed that some lubricants contain potentially detrimental elements (e.g. S, Sb) which can promote SCC of the common bolting materials. One of the most significant findings of this report is the observation that both A193 B7 and A540 B24 bolting materials are susceptible to transgranular stress corrosion cracking in demineralized H 2 O at 280 0 C in notched tensile tests

  1. Examination of Experimental Data for Irradiation - Creep in Nuclear Graphite

    Science.gov (United States)

    Mobasheran, Amir Sassan

    The objective of this dissertation was to establish credibility and confidence levels of the observed behavior of nuclear graphite in neutron irradiation environment. Available experimental data associated with the OC-series irradiation -induced creep experiments performed at the Oak Ridge National Laboratory (ORNL) were examined. Pre- and postirradiation measurement data were studied considering "linear" and "nonlinear" creep models. The nonlinear creep model considers the creep coefficient to vary with neutron fluence due to the densification of graphite with neutron irradiation. Within the range of neutron fluence involved (up to 0.53 times 10^{26} neutrons/m ^2, E > 50 KeV), both models were capable of explaining about 96% and 80% of the variation of the irradiation-induced creep strain with neutron fluence at temperatures of 600^circC and 900^circC, respectively. Temperature and reactor power data were analyzed to determine the best estimates for the actual irradiation temperatures. It was determined according to thermocouple readouts that the best estimate values for the irradiation temperatures were well within +/-10 ^circC of the design temperatures of 600^circC and 900 ^circC. The dependence of the secondary creep coefficients (for both linear and nonlinear models) on irradiation temperature was determined assuming that the variation of creep coefficient with temperature, in the temperature range studied, is reasonably linear. It was concluded that the variability in estimate of the creep coefficients is definitely not the results of temperature fluctuations in the experiment. The coefficients for the constitutive equation describing the overall growth of grade H-451 graphite were also studied. It was revealed that the modulus of elasticity and the shear modulus are not affected by creep and that the electrical resistivity is slightly (less than 5%) changed by creep. However, the coefficient of thermal expansion does change with creep. The consistency of

  2. The grading management of the quality assurance

    International Nuclear Information System (INIS)

    Ma Xiaozheng; Han Shufang; Yu Bei; Tian Xuehang

    2009-01-01

    This paper introduces the quality assurance grading management of the items, services and technology process on nuclear power plants (nuclear island, conventional island, BOP), such as the requirements and aim in the related code, guide, technical document, the requirements for the related units, the grading principle and grading, the considering method for the differences of QA requirements of the each QA grand, as well as the status and propositions in the QA grading management in China. (authors)

  3. Application of the Commercial Grade Item (CGI) Dedication Process for Procurement of Nuclear Safety Related Items at Nuclear Power Plant Krsko (NEK)

    International Nuclear Information System (INIS)

    Heruc, Z.; Pozar, J.

    1998-01-01

    CGI procurement is a process whereby parts are brought without imposing Appendix B Quality Assurance requirements on the supplier, and than dedicated for use in safety-related applications. The dedication process involves 1) based upon required safety function, an engineering evaluation to identify critical characteristic of the item and specification of acceptance criteria; and 2) quality control activities to ensure the item(s) supplied meets the acceptance criteria specified. CGI Dedication supports the supply of certified components/parts for the plant operation in an environment where the number of nuclear qualified suppliers diminishes. It requires a more active role of the plant personnel, therefore presenting an additional burden on human resources, but at the same time increases the technical KNOW-HOW and improves the confidence of test and inspection data presented in the certificates. Very often it is also cost beneficial. This paper is a continuation to last year presentation of the introduction of this method into NEK's procurement process and presents the current approach and some practical examples. (author)

  4. A Study of the Oxidation Behaviour of Pile Grade A (PGA) Nuclear Graphite Using Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM) and X-Ray Tomography (XRT).

    Science.gov (United States)

    Payne, Liam; Heard, Peter J; Scott, Thomas B

    2015-01-01

    Pile grade A (PGA) graphite was used as a material for moderating and reflecting neutrons in the UK's first generation Magnox nuclear power reactors. As all but one of these reactors are now shut down there is a need to understand the residual state of the material prior to decommissioning of the cores, in particular the location and concentration of key radio-contaminants such as 14C. The oxidation behaviour of unirradiated PGA graphite was studied, in the temperature range 600-1050°C, in air and nitrogen using thermogravimetric analysis, scanning electron microscopy and X-ray tomography to investigate the possibility of using thermal degradation techniques to examine 14C distribution within irradiated material. The thermal decomposition of PGA graphite was observed to follow the three oxidation regimes historically identified by previous workers with limited, uniform oxidation at temperatures below 600°C and substantial, external oxidation at higher temperatures. This work demonstrates that the different oxidation regimes of PGA graphite could be developed into a methodology to characterise the distribution and concentration of 14C in irradiated graphite by thermal treatment.

  5. Standard test methods for chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade aluminum oxide and aluminum oxide-boron carbide composite pellets

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1994-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade aluminum oxide and aluminum oxide-boron carbide composite pellets to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Boron by Titrimetry 7 to 13 Separation of Boron for Mass Spectrometry 14 to 19 Isotopic Composition by Mass Spectrometry 20 to 23 Separation of Halides by Pyrohydrolysis 24 to 27 Fluoride by Ion-Selective Electrode 28 to 30 Chloride, Bromide, and Iodide by Amperometric Microtitrimetry 31 to 33 Trace Elements by Emission Spectroscopy 34 to 46 1.3 The values stated in SI units are to be regarded as the standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. (F...

  6. Standard test method for analysis of isotopic composition of uranium in nuclear-grade fuel material by quadrupole inductively coupled plasma-mass spectrometry

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2000-01-01

    1.1 This test method is applicable to the determination of the isotopic composition of uranium (U) in nuclear-grade fuel material. The following isotopic weight percentages are determined using a quadrupole inductively coupled plasma-mass spectrometer (Q-ICP-MS): 233U, 234U, 235U, 236U, and 238U. The analysis can be performed on various material matrices after acid dissolution and sample dilution into water or dilute nitric (HNO3) acid. These materials include: fuel product, uranium oxide, uranium oxide alloys, uranyl nitrate (UNH) crystals, and solutions. The sample preparation discussed in this test method focuses on fuel product material but may be used for uranium oxide or a uranium oxide alloy. Other preparation techniques may be used and some references are given. Purification of the uranium by anion-exchange extraction is not required for this test method, as it is required by other test methods such as radiochemistry and thermal ionization mass spectroscopy (TIMS). This test method is also described i...

  7. Temporal follow-up of plasma parameter in an nuclear grade aluminum laser induced plasma at different laser energies by laser induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Karki, Vijay; Singh, Manjeet; Sarkar, Arnab

    2015-07-01

    We report spectroscopic studies of laser induced plasma (LIP) produced by ns – 532 nm - Nd:YAG laser light pulses for different laser energies (35, 45 and 60 mJ) on an nuclear grade aluminum sample in air at atmospheric pressure. The temporal history of the plasma is obtained by recording the emission features at predetermined delays and at a fixed gate width (2.5 ì s). The temporal profiles of excitation temperature (T e ), ionization temperature (T ion ) and electron number density (N e ) were determined from Boltzmann plot, Saha-Boltzmann equation and Stark broadening method, respectively. T e , T ion and N e , shows a power law decay pattern with increasing acquisition time delay. T e has a positive correlation with laser energy, but the T ion and N e differ negligibly from one laser energy to another. Again the rate of decay of T e increases with increasing laser energy but that of T ion is much slower and independent of laser energy. The follow up of the local thermodynamic equilibrium (LTE) conditions were evaluated using both McWhirter criterion and T e /T ion ratio for different delays and different energies to determine the temporal range in which LTE is satisfied. Both the methods concluded very similar results except for very high energy and small delay conditions, where T e /T ion ratio deviates from unity indicating non-LTE condition. The relative transition probabilities of Al transition (3sp4s: 4 P 2/5 →3sp 2 : 4P 3/2,5/2 ) and (4s: 2 S 1/2 → 3p: 2 P 1/2,3/2 ) were estimated and are in excellent agreement with the Kurucz database. These investigations provide an insight to optimize various parameters during LIBS analysis of aluminum based matrices. (author)

  8. Nuclear

    International Nuclear Information System (INIS)

    2014-01-01

    This document proposes a presentation and discussion of the main notions, issues, principles, or characteristics related to nuclear energy: radioactivity (presence in the environment, explanation, measurement, periods and activities, low doses, applications), fuel cycle (front end, mining and ore concentration, refining and conversion, fuel fabrication, in the reactor, back end with reprocessing and recycling, transport), the future of the thorium-based fuel cycle (motivations, benefits and drawbacks), nuclear reactors (principles of fission reactors, reactor types, PWR reactors, BWR, heavy-water reactor, high temperature reactor of HTR, future reactors), nuclear wastes (classification, packaging and storage, legal aspects, vitrification, choice of a deep storage option, quantities and costs, foreign practices), radioactive releases of nuclear installations (main released radio-elements, radioactive releases by nuclear reactors and by La Hague plant, gaseous and liquid effluents, impact of releases, regulation), the OSPAR Convention, management and safety of nuclear activities (from control to quality insurance, to quality management and to sustainable development), national safety bodies (mission, means, organisation and activities of ASN, IRSN, HCTISN), international bodies, nuclear and medicine (applications of radioactivity, medical imagery, radiotherapy, doses in nuclear medicine, implementation, the accident in Epinal), nuclear and R and D (past R and D programmes and expenses, main actors in France and present funding, main R and D axis, international cooperation)

  9. Objective malignancy grading of squamous cell carcinoma of the lung. Stereologic estimates of mean nuclear size are of prognostic value, independent of clinical stage of disease

    DEFF Research Database (Denmark)

    Ladekarl, M; Bæk-Hansen, T; Henrik-Nielsen, R

    1995-01-01

    a projection microscope and a simple test system in fields of vision systematically selected from the whole tumor area of one routine section, five quantitative histopathologic variables were estimated: the mean nuclear volume, the mean nuclear profile area, the density of nuclear profiles, the volume fraction...... of nuclei to tissue, and the number of mitotic profiles per 10(3) nuclear profiles. For each patient, information was recorded regarding sex, age at diagnosis, and clinical stage of disease.RESULTS: Single-factor analyses showed that a favorable prognosis was associated with early clinical stages (Stages I...... and II) and young age (P stage, age, and mean nuclear...

  10. Objective malignancy grading of squamous cell carcinoma of the lung. Stereologic estimates of mean nuclear size are of prognostic value, independent of clinical stage of disease

    DEFF Research Database (Denmark)

    Ladekarl, M; Bæk-Hansen, T; Henrik-Nielsen, R

    1995-01-01

    a projection microscope and a simple test system in fields of vision systematically selected from the whole tumor area of one routine section, five quantitative histopathologic variables were estimated: the mean nuclear volume, the mean nuclear profile area, the density of nuclear profiles, the volume fraction...... of nuclei to tissue, and the number of mitotic profiles per 10(3) nuclear profiles. For each patient, information was recorded regarding sex, age at diagnosis, and clinical stage of disease. RESULTS: Single-factor analyses showed that a favorable prognosis was associated with early clinical stages (Stages I...... and II) and young age (P stage, age, and mean nuclear...

  11. Nuclear

    International Nuclear Information System (INIS)

    Anon.

    2000-01-01

    The first text deals with a new circular concerning the collect of the medicine radioactive wastes, containing radium. This campaign wants to incite people to let go their radioactive wastes (needles, tubes) in order to suppress any danger. The second text presents a decree of the 31 december 1999, relative to the limitations of noise and external risks resulting from the nuclear facilities exploitation: noise, atmospheric pollution, water pollution, wastes management and fire prevention. (A.L.B.)

  12. Nuclear

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    Short communication. Full text included in abstract. The general manager of the Cigar Lake uranium mine in northern Saskatchewan, George Peebles, says high radiation levels in the mine will prevent miners from working in direct contact with the underground ore. The exceptionally high grade of uranium will force Cigar Lake Mining Corp. to adopt unconventional mining methods in which the equipment is controlled from remote locations. Mr. Peebles said that the uranium deposits at Cigar Lake are 100 times richer than the deposits at older uranium mines in Ontario, where workers can spend a full shift in direct contact with the uranium. Because the deposits are so rich, workers cannot be exposed to the gamma radiation and radon gas for more the a few hours at a time. The mining corporation will probably use the 'raise-boring' method, in which a drill is located in a tunnel above the ore zone. A vertical hole is then drilled through the ore. Under this method, several metres of rock will separate the drill operator from the uranium. The method is commonly used in hard-rock mining, but it has never been required in uranium mining. In addition, the corporation will have to use extensive ventilation to get rid of the radon gas in the mine. Moreover, because of ground stability problems at Cigar Lake, the corporation will find it difficult to use conventional drilling and blasting techniques. Special ground-support measures will be needed. Finally, the corporation will have to take precautions to deal with groundwater in the area. If the flow is not restricted, the mine would receive 2,000 cubic metres of water an hour, Mr. Peebles said. The Cigar Lake mine is the largest high-grade uranium deposit in the world. It contains an estimated 150,000 metric tons of uranium, mostly in ore with an average grade of 12% uranium. The uranium deposits are so rich that the mine can produce 5.5 million kilograms of uranium annually from slightly more than 90 tons of ore excavated each day

  13. Fatigue crack growth characteristics of a533 brade b glass i plate in an environment of high-temperature primary grade nuclear reactor water

    International Nuclear Information System (INIS)

    Mager, T.R.; Moon, D.M.; Landes, J.D.

    1976-01-01

    To characterize the effect of environment on crack growth rate properties of reactor pressure vessel materials, a program was initiated as part of the Heavy Section Steel Technology Program (HSST) to evaluate the effect of Pressurized Water Reactor (PWR) and Boiling Water Reactor (BWR) primary grade coolant environments. The experiments included such variables as frequency, temperature and R ratio. This paper describes the investigation and presents the results of a fracture mechanics evaluation of the fatigue crack growth rate tests of A533 Grade B Class 1 steel plate material in an environment of primary reactor grade water at 550 0 F (288 0 C). A compliance crack growth monitoring technique was utilized to measure the crack growth. The compliance crack length monitor uses a linear variable differential transformer (LVDT) to measure the specimen front face displacement which is converted to crack length by the appropriate compliance calibration curve. The crack growth rate tests were conducted on constant load universal fatigue machines, under sinusoidal tension to tension loading conditions. Tests showed an increase in growth rates at a frequency of 1 cpm over previous results obtained at frequencies of 60 cpm and higher. This increase, the general character of the crack growth rate versus the $DELTA$K curve, and the results from fractographic studies, all indicated that stress corrosion cracking might have occurred for this material and environment. However, a specimen loaded statically in a PWR environment showed no static load crack growth. 13 refs

  14. Quality assurance grading criteria for plant systems and components: Results from a pilot plant project at Grand Gulf Nuclear Station. Final report

    International Nuclear Information System (INIS)

    Parkinson, W.J.

    1995-12-01

    As part of the original design of a nuclear power plant, the NSSS vendor, architect/engineer and utility identified structures, systems and components (SSCs) as safety related and assigned them to a Q-list. A Q-list is usually very large, e.g. 75,000 components, which creates large ongoing annual operating costs for the utility. Operating experience and the greater knowledge of plant systems safety accumulated during the past 20 years have suggested that many components are not truly important to safety and do not warrant the Q-classification and the associated costs. The completion of Probabilistic Safety Analyses (PSAs) for many nuclear power plants has contributed to this greater knowledge. This report describes a practical application of PSA technology to modify the existing QA program at the Grand Gulf Nuclear Station. Section 1 introduces the term, QA Safety Significant (QASS), and relates it to the existing term, ''safety related''. Section 2 describes six deterministic criteria as a basis for classifying systems as QASS or non-QASS. An expert panel reviewed 421 systems at Grand Gulf Nuclear Station and identified 42 of them as QASS. All components in non-QASS systems are classified as non-QASS. For QASS systems, Section 3 describes five deterministic criteria for classifying components as QASS or non-QASS. By using these two sets of criteria, the expert panel found that the number of components requiring full QA compliance could be reduced by 24%. These results are summarized in Section 4

  15. Self-diffusion nuclear magnetic resonance, microstructure transitions, and solubilization capacity of phytosterols and cholesterol in Winsor IV food-grade microemulsions

    DEFF Research Database (Denmark)

    Spernath, Aviram; Yaghmur, Anan; Aserin, Abraham

    2003-01-01

    Microemulsions are of growing interest to the food industry as vehicles for delivering and enhancing solubilization of natural food supplements with nutritional and health benefits. The incorporation of molecular phytosterols, cholesterol-lowering agents, in food products is of great interest...... to the food industry. In this work is demonstrated the use of water dilutable food-grade microemulsions consisting of ethoxylated sorbitan ester (Tween 60), water, R-(+)-limonene, ethanol, and propylene glycol as vehicles for enhancing the phytosterols solubilization. Phytosterols were solubilized up to 12...... times more than the dissolution capacity of the oil [R-(+)-limonene] for the same compounds. The solubilization capacity of phytosterols and cholesterol along a dilution line in a pseudo-ternary phase diagram [on this dilution line the weight ratio of R-(+)-limonene/ethanol/Tween 60 is constant at 1...

  16. Teachers' Grading Decision Making

    Science.gov (United States)

    Isnawati, Ida; Saukah, Ali

    2017-01-01

    This study investigated teachers' grading decision making, focusing on their beliefs underlying their grading decision making, their grading practices and assessment types, and factors they considered in grading decision making. Two teachers from two junior high schools applying different curriculum policies in grade reporting in Indonesian…

  17. Study and full-scale test of a high-velocity grade-crossing simulated accident of a locomotive and a nuclear-spent-fuel shipping cask

    International Nuclear Information System (INIS)

    Huerta, M.; Yoshimura, H.R.

    1983-02-01

    This report described structural analyses of a high-speed impact between a locomotive and a tractor-trailer system carrying a nuclear-spent-fuel shipping cask. The analyses included both mathematical and physical scale-modeling of the system. The report then describes the full-scale test conducted as part of the program. The system response is described in detail, and a comparison is made between the analyses and the actual hardware response as observed in the full-scale test. 34 figures

  18. Student Attitudes Toward Grades and Grading Practices.

    Science.gov (United States)

    Stallings, William M.; Leslie, Elwood K.

    The result of a study designed to assess student attitudes toward grading practices are discussed. Questionnaire responses of 3439 students in three institutions were tabulated. Responses were generally negative toward conventional grading systems. (MS)

  19. Grading of quality assurance requirements

    International Nuclear Information System (INIS)

    1991-01-01

    The present Manual provides guidance and illustrative examples for applying a method by which graded quality assurance requirements may be determined and adapted to the items and services of a nuclear power plant in conformance with the requirements of the IAEA Nuclear Safety Standards (NUSS) Code and Safety Guides on quality assurance. The Manual replaces the previous publication IAEA-TECDOC-303 on the same subject. Various methods of grading quality assurance are available in a number of Member States. During the development of the present Manual it was not considered practical to attempt to resolve the differences between those methods and it was preferred to identify and benefit from the good practices available in all the methods. The method presented in this Manual deals with the aspects of management, documentation, control, verification and administration which affect quality. 1 fig., 4 tabs

  20. Issues in the use of Weapons-Grade MOX Fuel in VVER-1000 Nuclear Reactors: Comparison of UO2 and MOX Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Carbajo, J.J.

    2005-05-27

    The purpose of this report is to quantify the differences between mixed oxide (MOX) and low-enriched uranium (LEU) fuels and to assess in reasonable detail the potential impacts of MOX fuel use in VVER-1000 nuclear power plants in Russia. This report is a generic tool to assist in the identification of plant modifications that may be required to accommodate receiving, storing, handling, irradiating, and disposing of MOX fuel in VVER-1000 reactors. The report is based on information from work performed by Russian and U.S. institutions. The report quantifies each issue, and the differences between LEU and MOX fuels are described as accurately as possible, given the current sources of data.

  1. Characterization of nuclear graphite elastic properties using laser ultrasonic methods

    Science.gov (United States)

    Zeng, Fan W.; Han, Karen; Olasov, Lauren R.; Gallego, Nidia C.; Contescu, Cristian I.; Spicer, James B.

    2015-05-01

    Laser ultrasonic methods have been used to characterize the elastic behaviors of commercially-available and legacy nuclear graphites. Since ultrasonic techniques are sensitive to various aspects of graphite microstructure including preferred grain orientation, microcrack orientation and porosity, laser ultrasonics is a candidate technique for monitoring graphite degradation and structural integrity in environments expected in high-temperature, gas-cooled nuclear reactors. Aspects of materials texture can be assessed by studying ultrasonic wavespeeds as a function of propagation direction and polarization. Shear wave birefringence measurements, in particular, can be used to evaluate elastic anisotropy. In this work, laser ultrasonic measurements of graphite moduli have been made to provide insight into the relationship between the microstructures and the macroscopic stiffnesses of these materials. In particular, laser ultrasonic measurements have been made using laser line sources to produce shear waves with specific polarizations. By varying the line orientation relative to the sample, shear wave birefringence measurements have been recorded. Results from shear wave birefringence measurements show that an isostatically molded graphite, such as PCIB, behaves isotropically, while an extruded graphite, such as H-451, displays significant ultrasonic texture. Graphites have complicated microstructures that depend on the manufacturing processes used, and ultrasonic texture in these materials could originate from grain orientation and preferred microcrack alignment. Effects on material isotropy due to service related microstructural changes are possible and the ultimate aim of this work is to determine the degree to which these changes can be assessed nondestructively using laser ultrasonics measurements.

  2. Anaplasia and grading in medulloblastomas.

    Science.gov (United States)

    Eberhart, Charles G; Burger, Peter C

    2003-07-01

    The variable clinical outcomes of medulloblastoma patients have prompted a search for markers with which to tailor therapies to individuals. In this review, we discuss clinical, histological and molecular features that can be used in such treatment customization, focusing on how histopathological grading can impact both patient care and research on the molecular basis of CNS embryonal tumors. Medulloblastomas span a histological spectrum ending in overtly malignant large cell/anaplastic lesions characterized by increased nuclear size, marked cytological anaplasia, and increased mitotic and apoptotic rates. These "high-grade" lesions make up approximately one quarter of medulloblastomas, and recur and metastasize more frequently than tumors lacking anaplasia. We believe anaplastic change represents a type of malignant progression common to many medulloblastoma subtypes and to other CNS embryonal lesions as well. Correlation of these histological changes with the accumulation of genetic events suggests a model for the histological and molecular progression of medulloblastoma.

  3. On arbitrarily graded rings

    Indian Academy of Sciences (India)

    58

    paper is devoted to the study of arbitrary rings graded through arbitrary sets. .... which recover certain multiplicative relations among the homogeneous components ... instance the case in which the grading set A is an Abelian group, where the ...

  4. Graded manifolds and supermanifolds

    International Nuclear Information System (INIS)

    Batchelor, M.

    1984-01-01

    In this paper, a review is presented on graded manifolds and supermanifolds. Many theorems, propositions, corrollaries, etc. are given with proofs or sketch proofs. Graded manifolds, supereuclidian space, Lie supergroups, etc. are dealt with

  5. GRADE Equity Guidelines 3

    DEFF Research Database (Denmark)

    Welch, Vivian A; Akl, Elie A; Pottie, Kevin

    2017-01-01

    OBJECTIVE: The aim of this paper is to describe a conceptual framework for how to consider health equity in the GRADE (Grading Recommendations Assessment and Development Evidence) guideline development process. STUDY DESIGN AND SETTING: Consensus-based guidance developed by the GRADE working grou...

  6. Low temperature nuclear heat

    Energy Technology Data Exchange (ETDEWEB)

    Kotakorpi, J.; Tarjanne, R. [comps.

    1977-08-01

    The meeting was concerned with the use of low grade nuclear heat for district heating, desalination, process heat, and agriculture and aquaculture. The sessions covered applications and demand, heat sources, and economics.

  7. Burning weapons-grade plutonium in reactors

    International Nuclear Information System (INIS)

    Newman, D.F.

    1993-06-01

    As a result of massive reductions in deployed nuclear warheads, and their subsequent dismantlement, large quantities of surplus weapons- grade plutonium will be stored until its ultimate disposition is achieved in both the US and Russia. Ultimate disposition has the following minimum requirements: (1) preclude return of plutonium to the US and Russian stockpiles, (2) prevent environmental damage by precluding release of plutonium contamination, and (3) prevent proliferation by precluding plutonium diversion to sub-national groups or nonweapons states. The most efficient and effective way to dispose of surplus weapons-grade plutonium is to fabricate it into fuel and use it for generation of electrical energy in commercial nuclear power plants. Weapons-grade plutonium can be used as fuel in existing commercial nuclear power plants, such as those in the US and Russia. This recovers energy and economic value from weapons-grade plutonium, which otherwise represents a large cost liability to maintain in safeguarded and secure storage. The plutonium remaining in spent MOX fuel is reactor-grade, essentially the same as that being discharged in spent UO 2 fuels. MOX fuels are well developed and are currently used in a number of LWRs in Europe. Plutonium-bearing fuels without uranium (non-fertile fuels) would require some development. However, such non-fertile fuels are attractive from a nonproliferation perspective because they avoid the insitu production of additional plutonium and enhance the annihilation of the plutonium inventory on a once-through fuel cycle

  8. High grade magnesium from waste bittern

    International Nuclear Information System (INIS)

    El-Yamani, I.S.; Farah, M.Y.; Isaac, S.L.

    1979-01-01

    The production of high grade magnesia for nuclear purposes from sea water by use of both aqueous and gaseous ammonia has been described. The effect of precipitating conditions on the settling rate and magnesium recovery, was thoroughly examined. Ammonia gas approach was recommended and justified

  9. Graded gauge theory

    International Nuclear Information System (INIS)

    Kerner, R.

    1983-01-01

    The mathematical background for a graded extension of gauge theories is investigated. After discussing the general properties of graded Lie algebras and what may serve as a model for a graded Lie group, the graded fiber bundle is constructed. Its basis manifold is supposed to be the so-called superspace, i.e. the product of the Minkowskian space-time with the Grassmann algebra spanned by the anticommuting Lorentz spinors; the vertical subspaces tangent to the fibers are isomorphic with the graded extension of the SU(N) Lie algebra. The connection and curvature are defined then on this bundle; the two different gradings are either independent of each other, or may be unified in one common grading, which is equivalent to the choice of the spin-statistics dependence. The Yang-Mills lagrangian is investigated in the simplified case. The conformal symmetry breaking is discussed, as well as some other physical consequences of the model. (orig.)

  10. Nuclear energy and nuclear weapons proliferation

    International Nuclear Information System (INIS)

    1989-01-01

    A summary of the report dispatched in the middle of 1978 by the Atlantic Council of United States, organized by North American citizens, is presented. The report considers the relation between the production of nucleoelectric energy and the capacity of proliferation of nuclear weapons. The factors which affect the grade of proliferation risk represented by the use of nuclear energy in the world comparing this risk with the proliferation risks independently of nuclear energy, are examined. (M.C.K.) [pt

  11. Reliability Analysis for Safety Grade PLC(POSAFE-Q)

    International Nuclear Information System (INIS)

    Choi, Kyung Chul; Song, Seung Whan; Park, Gang Min; Hwang, Sung Jae

    2012-01-01

    Safety Grade PLC(Programmable Logic Controller), POSAFE-Q, was developed recently in accordance with nuclear regulatory and requirements. In this paper, describe reliability analysis for digital safety grade PLC (especially POSAFE-Q). Reliability analysis scope is Prediction, Calculation of MTBF (Mean Time Between Failure), FMEA (Failure Mode Effect Analysis), PFD (Probability of Failure on Demand). (author)

  12. Typing and grading of cytological category C5 breast lesions

    International Nuclear Information System (INIS)

    Zafar, N.; Jamal, S.; Mamoon, N.; Luqman, M.; Anwar, M.

    2005-01-01

    Objective: To determine the tumour type, cytological grade and nuclear grade on fine-needle aspiration smears in cytological category C5 breast lesions and compare them with histopathological findings. Subjects and Methods: Out of all patients referred to AFIP, Rawalpindi for fine-needle aspiration of breast masses, those adjudged C5 (malignant) were chosen for this study. History, clinical details and mammographic findings were noted. Aspirated smears were examined and an attempt was made to ascertain tumour type, cytological grade and nuclear grade. On excision of these lesions, the cytological findings were compared with those on paraffin-embedded histological sections. Results: A total of 71 patients were included in this study. Of these, 64 (90.14%) were cytologically diagnosed as ductal carcinoma, 4 (5.63%) lobular carcinoma, 2 (2.82%) mucinous carcinoma and 1 (1.41%) as medullary carcinoma. Seventy (98.60%) tumours were correctly typed on aspiration smears. Sixty-eight (95.77%) cases were cytologically graded with accuracy. Nuclear grading was even better on cytology and, excluding one malignant lymphoma, all 70 (100%) smears were assessed correctly. Conclusion: Overall efficiency of the tumour typing, cytological grading and nuclear grading on aspirated material turned out to be quite accurate. In expert hands, cytological examination can be of great help in pre-operative planning and in cases where tumour morphology in paraffin-embedded material has been distorted by neo-adjuvant therapy prior to excision. (author)

  13. Nuclear facilities

    International Nuclear Information System (INIS)

    Anon.

    2002-01-01

    During September and October 2001, 15 events were recorded on the first grade and 1 on the second grade of the INES scale. The second grade event is in fact a re-classification of an incident that occurred on the second april 2001 at Dampierre power plant. This event happened during core refueling, a shift in the operation sequence led to the wrong positioning of 113 assemblies. A preliminary study of this event shows that this wrong positioning could have led, in other circumstances, to the ignition of nuclear reactions. Even in that case, the analysis made by EDF shows that the consequences on the staff would have been limited. Nevertheless a further study has shown that the existing measuring instruments could not have detected the power increase announcing the beginning of the chain reaction. The investigation has shown that there were deficiencies in the control of the successive operations involved in refueling. EDF has proposed a series of corrective measures to be implemented in all nuclear power plants. The other 15 events are described in the article. During this period 121 inspections have been made in nuclear facilities. (A.C.)

  14. Graded tensor calculus

    International Nuclear Information System (INIS)

    Scheunert, M.

    1982-10-01

    We develop a graded tensor calculus corresponding to arbitrary Abelian groups of degrees and arbitrary commutation factors. The standard basic constructions and definitions like tensor products, spaces of multilinear mappings, contractions, symmetrization, symmetric algebra, as well as the transpose, adjoint, and trace of a linear mapping, are generalized to the graded case and a multitude of canonical isomorphisms is presented. Moreover, the graded versions of the classical Lie algebras are introduced and some of their basic properties are described. (orig.)

  15. Use of commercial grade item dedication to reduce procurement costs

    International Nuclear Information System (INIS)

    Rosch, F.

    1995-01-01

    In the mid-1980s, the Nuclear Regulatory Industry (NRC) began inspecting utility practices of procuring and dedicating commercial grade items intended for plant safety-related applications. As a result of the industry efforts to address NRC concerns, nuclear utilities have enhanced existing programs and procedures for dedication of commercial grade items. Though these programs were originally enhanced to meet NRC concerns, utilities have discovered that the dedication of commercial grade items can also reduce overall procurement costs. This paper will discuss the enhancement of utility dedication programs and demonstrates how utilities have utilized them to reduce procurement costs

  16. Classroom: Efficient Grading

    Science.gov (United States)

    Shaw, David D.; Pease, Leonard F., III.

    2014-01-01

    Grading can be accelerated to make time for more effective instruction. This article presents specific time management strategies selected to decrease administrative time required of faculty and teaching assistants, including a multiple answer multiple choice interface for exams, a three-tier grading system for open ended problem solving, and a…

  17. Grain Grading and Handling.

    Science.gov (United States)

    Rendleman, Matt; Legacy, James

    This publication provides an introduction to grain grading and handling for adult students in vocational and technical education programs. Organized in five chapters, the booklet provides a brief overview of the jobs performed at a grain elevator and of the techniques used to grade grain. The first chapter introduces the grain industry and…

  18. Vascular grading of angiogenesis

    DEFF Research Database (Denmark)

    Hansen, S; Grabau, D A; Sørensen, Flemming Brandt

    2000-01-01

    The study aimed to evaluate the prognostic value of angiogenesis by vascular grading of primary breast tumours, and to evaluate the prognostic impact of adding the vascular grade to the Nottingham Prognostic Index (NPI). The investigation included 836 patients. The median follow-up time was 11...... years and 4 months. The microvessels were immunohistochemically stained by antibodies against CD34. Angiogenesis was graded semiquantitatively by subjective scoring into three groups according to the expected number of microvessels in the most vascular tumour area. The vascular grading between observers...... for 24% of the patients, who had a shift in prognostic group, as compared to NPI, and implied a better prognostic dissemination. We concluded that the angiogenesis determined by vascular grading has independent prognostic value of clinical relevance for patients with breast cancer....

  19. Vascular grading of angiogenesis

    DEFF Research Database (Denmark)

    Hansen, S; Grabau, D A; Sørensen, Flemming Brandt

    2000-01-01

    The study aimed to evaluate the prognostic value of angiogenesis by vascular grading of primary breast tumours, and to evaluate the prognostic impact of adding the vascular grade to the Nottingham Prognostic Index (NPI). The investigation included 836 patients. The median follow-up time was 11...... years and 4 months. The microvessels were immunohistochemically stained by antibodies against CD34. Angiogenesis was graded semiquantitatively by subjective scoring into three groups according to the expected number of microvessels in the most vascular tumour area. The vascular grading between observers...... impact for 24% of the patients, who had a shift in prognostic group, as compared to NPI, and implied a better prognostic dissemination. We concluded that the angiogenesis determined by vascular grading has independent prognostic value of clinical relevance for patients with breast cancer....

  20. Illicit Nuclear Trafficking Scams

    International Nuclear Information System (INIS)

    Moore, G.M.

    2010-01-01

    Nuclear Trafficking Scams are situations where the scam artist(s) offer something (material or information) that is not what he/she/they represent it to be. Example of a scam is when attempt is made to sell fake nuclear material. The offered material may not be nuclear material or may be of a lower grade. The offered material may not actually exist . Radioactive material may be offered as nuclear material. A small sample of actual nuclear material may be offered, but the bulk material may be something else.

  1. Synergy in the areas of NPP nuclear safety and nuclear security

    International Nuclear Information System (INIS)

    Dybach, A.M.; Kuzmyak, I.Ya.; Kukhotskij, A.V.

    2013-01-01

    The paper considers the question of synergy between nuclear safety and nuclear security. Special attention is paid to identifying interface of the two areas of safety and definition of common principles for nuclear security and nuclear safety measures. The principles of defense in depth, safety culture and graded approach are analyzed in detail.Specific features characteristic of nuclear safety and security are outlined

  2. Histopathologic grading of anaplasia in retinoblastoma.

    Science.gov (United States)

    Mendoza, Pia R; Specht, Charles S; Hubbard, G Baker; Wells, Jill R; Lynn, Michael J; Zhang, Qing; Kong, Jun; Grossniklaus, Hans E

    2015-04-01

    To determine whether the degree of tumor anaplasia has prognostic value by evaluating its correlation with high-risk histopathologic features and clinical outcomes in a series of retinoblastoma patients. Retrospective clinicopathologic study. The clinical and pathologic findings in 266 patients who underwent primary enucleation for retinoblastoma were reviewed. The histologic degree of anaplasia was graded as retinocytoma, mild, moderate, or severe as defined by increasing cellular pleomorphism, number of mitoses, nuclear size, and nuclear hyperchromatism. Nuclear morphometric characteristics were measured. The clinical and pathologic data of 125 patients were compared using Kaplan-Meier estimates of survival. Fisher exact test and multivariate regression were used to analyze the association between anaplasia grade and high-risk histologic features. Increasing grade of anaplasia was associated with decreased overall survival (P = .003) and increased risk of metastasis (P = .0007). Histopathologic features that were associated with anaplasia included optic nerve invasion (P anaplasia grading as predictors of distant metastasis and death showed that high-risk histopathology was statistically significant as an independent predictor (P = .01 for metastasis, P = .03 for death) but anaplasia was not (P = .63 for metastasis, P = .30 for death). In the absence of high-risk features, however, severe anaplasia identified an additional risk for metastasis (P = .0004) and death (P = .01). Grading of anaplasia may be a useful adjunct to standard histopathologic criteria in identifying retinoblastoma patients who do not have high-risk histologic features but still have an increased risk of metastasis and may need adjuvant therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. CRA Grade Inflation

    OpenAIRE

    Kenneth H. Thomas

    2000-01-01

    Community Reinvestment Act of 1977 (CRA) ratings and performance evaluations are the only bank and thrift exam findings disclosed by financial institution regulators. Inflation of CRA ratings has been alleged by community activists for two decades, but there has been no quantification or empirical investigation of grade inflation. Using a unique grade inflation methodology on actual ratings and evaluation data for 1,407 small banks and thrifts under the revised CRA regulations, this paper con...

  4. Functionally graded materials

    CERN Document Server

    Mahamood, Rasheedat Modupe

    2017-01-01

    This book presents the concept of functionally graded materials as well as their use and different fabrication processes. The authors describe the use of additive manufacturing technology for the production of very complex parts directly from the three dimension computer aided design of the part by adding material layer after layer. A case study is also presented in the book on the experimental analysis of functionally graded material using laser metal deposition process.

  5. Final report on graphite irradiation test OG-2

    International Nuclear Information System (INIS)

    Price, R.J.; Beavan, L.A.

    1975-01-01

    Results are presented of dimensional, thermal expansivity, thermal conductivity, Young's modulus, and tensile strength measurements on specimens of nuclear graphites irradiated in capsule OG-2. About half the irradiation space was allocated to H-451 near-isotropic petroleum-coke-based graphite or its subsized prototype grade H-429. Most of these specimens had been previously irradiated. Virgin specimens of another near-isotropic graphite, grade TS-1240, were irradiated. Some previously irradiated specimens of needle-coke-based H-327 graphite and pitch-coke-based P 3 JHAN were also included

  6. Correlation of DNA content and nucleomorphometric features with World Health Organization grading of meningiomas.

    Science.gov (United States)

    Grunewald, J P; Röhl, F W; Kirches, E; Dietzmann, K

    1998-02-01

    Many studies dealing with extracranial cancer showed a strong correlation of DNA ploidy to a poor clinical outcome, recurrence, or malignancy. In brain tumors, analysis of DNA content did not always provided significant diagnostic information. In this study, DNA density and karyometric parameters of 50 meningiomas (26 Grade I, 10 Grade II, 14 Grade III) were quantitatively evaluated by digital cell image analyses of Feulgen-stained nuclei. In particular, the densitometric parameter SEXT, which describes nuclear DNA content, as well as the morphometric values LENG (a computer-assisted measurement of nuclear circumference), AREA (a computer-assisted measurement of nuclear area), FCON (a parameter that describes nuclear roundness), and CONC (a describing nuclear contour), evaluated with the software IMAGE C, were correlated to World Health Organization (WHO) grading using univariate and multivariate methods. AREA and LENG values showed significant differences between tumors of Grades I and III. FCON values were unable to distinguish WHO Grade III from Grade I/II but were useful in clearly separating Grade II from Grade I tumors. CONC values detected differences between WHO Grades II and I/III tumors but not between the latter. SEXT values clearly distinguished Grade III from Grade I/II tumors. The 1c, 2c, 2.5c, and 5c exceeding rates showed no predictive values. Only the 6c exceeding rate showed a significant difference between Grades I and III. These results outline the characteristic features of the atypical (Grade II) meningiomas, which make them a recognizable tumor entity distinct from benign and anaplastic meningiomas. The combination of DNA densitometric and morphometric findings seems to be a powerful addition to the histopathologic classification of meningiomas, as suggested by the WHO.

  7. Contractions from grading

    Science.gov (United States)

    Krishnan, Chethan; Raju, Avinash

    2018-04-01

    We note that large classes of contractions of algebras that arise in physics can be understood purely algebraically via identifying appropriate Zm-gradings (and their generalizations) on the parent algebra. This includes various types of flat space/Carroll limits of finite and infinite dimensional (A)dS algebras, as well as Galilean and Galilean conformal algebras. Our observations can be regarded as providing a natural context for the Grassmann approach of Krishnan et al. [J. High Energy Phys. 2014(3), 36]. We also introduce a related notion, which we call partial grading, that arises naturally in this context.

  8. Homemade nuclear bomb syndrome

    International Nuclear Information System (INIS)

    Nelson, W.E.

    1977-01-01

    This work discusses the hindrances that a malefactor would have to overcome in his attempts to acquire the necessary materials for the construction of a nuclear device. The methods of nuclear materials control that were used in the past, are presently employed, and are envisioned for the future are discussed. Use denial methods are examined and are shown to complement the nuclear materials control programs. International nuclear materials controls are also discussed. The characteristics of reactor grade materials are presented. The problems associated with attempting to work with reactor grade plutonium; radiation hazard, metallurgical problems, self heating, predetonation, etc., are discussed. Also presented is a method for approximating the energy release from a nuclear device. A risk versus benefit study is presented. The societal risk method of examining the nuclear materials control programs is discussed and shown to be a valuable tool for pointing out possible weaknesses in the nuclear materials control programs. A comparison of plutonium and more conventional hazardous substances is presented in order to show that the desirability of plutonium as a terrorist weapon has been greatly overrated. Also discussed is the recent policy statement by President Carter that the United States will forego the utilization of plutonium in order to halt the proliferation of nuclear weapons. The problems that will arise from this policy are noted. It is concluded that while the present programs aimed at strengthening the nuclear materials controls should continue to be pursued, the public has been misled as to the ease of acquiring the requisite materials and the construction of a nuclear device. It is also clearly understood that while reactor grade materials do not lend themselves to ready assembly of a nuclear device, they must still be effectively safeguarded

  9. Does nuclear power lead to nuclear weapons

    International Nuclear Information System (INIS)

    Prawitz, J.

    1977-01-01

    It is pointed out that 'reactor grade' plutonium usually contains about 30 % Pu240 and is unsuitable for weapons. While it is possible to obtain an explosion, it is more difficult to initiate one and its effect, which will be considerably less than with bomb grade plutonium, is difficult to predict. The critical mass will be larger and more cooling required. The proliferation problem is then discussed and the four aspects, vertical, horizontal, sub-national and revolutionary, mentioned. In connection with nuclear power it is the second and third aspects which are of interest. In discussing the possibility of terrorist groups obtaining plutonium, a study by the Swedish Defence Research Institute is quoted as estimating that 10-20 qualified specialists and several years secret preparation would be necessary to make a nuclear weapon. Other authors, e.g. Ted Taylor, have maintained that it would be much easier, but examples of 'student designs' are primitive and unlikely to detonate. Even so, it is emphasised that safeguards and physical security are necessary. Horizontal proliferation is a more real problem and the NPT and IAEA safeguards are discussed in this connection. In conclusion the question of whether the proliferation of nuclear weapons via nuclear power can be prevented cannot be answered with a clear yes or no. Certain states may use nuclear weapon potential as a bargaining factor. However the decision to acquire nuclear weapons is political and while a nuclear power industry would be of help, it would not be decisively so. (JIW)

  10. Endangered Animals. Second Grade.

    Science.gov (United States)

    Popp, Marcia

    This second grade teaching unit centers on endangered animal species around the world. Questions addressed are: What is an endangered species? Why do animals become extinct? How do I feel about the problem? and What can I do? Students study the definition of endangered species and investigate whether it is a natural process. They explore topics…

  11. Calculating Student Grades.

    Science.gov (United States)

    Allswang, John M.

    1986-01-01

    This article provides two short microcomputer gradebook programs. The programs, written in BASIC for the IBM-PC and Apple II, provide statistical information about class performance and calculate grades either on a normal distribution or based on teacher-defined break points. (JDH)

  12. Grades as Information

    Science.gov (United States)

    Grant, Darren

    2007-01-01

    We determine how much observed student performance in microeconomics principles can be attributed, inferentially, to three kinds of student academic "productivity," the instructor, demographics, and unmeasurables. The empirical approach utilizes an ordered probit model that relates student performance in micro to grades in prior…

  13. First Grade Baseline Evaluation

    Science.gov (United States)

    Center for Innovation in Assessment (NJ1), 2013

    2013-01-01

    The First Grade Baseline Evaluation is an optional tool that can be used at the beginning of the school year to help teachers get to know the reading and language skills of each student. The evaluation is composed of seven screenings. Teachers may use the entire evaluation or choose to use those individual screenings that they find most beneficial…

  14. The Fifth Grade Classroom.

    Science.gov (United States)

    Hartman, Michael; And Others

    An interdisciplinary design project report investigates the relationship of the fifth grade educational facility to the student and teacher needs in light of human and environmental factors. The classroom, activity and teaching spaces are analyzed with regard to the educational curriculum. Specifications and design criteria concerning equipment…

  15. Cutting Class Harms Grades

    Science.gov (United States)

    Taylor, Lewis A., III

    2012-01-01

    An accessible business school population of undergraduate students was investigated in three independent, but related studies to determine effects on grades due to cutting class and failing to take advantage of optional reviews and study quizzes. It was hypothesized that cutting classes harms exam scores, attending preexam reviews helps exam…

  16. Grading standards, prepared by the Configuration Management Office

    International Nuclear Information System (INIS)

    Cort, G.; Donahue, S.; Frank, J.; Perkins, B.; Wrye, J.

    1994-01-01

    This report describes the grading methodology used by the organization to determine the required levels of configuration management for all controlled elements that are part of the nuclear facility and its operation. The goal is to have a flexible grading system that accurately reflects the overall operational environment. The grading methodology should identify which items, processes, and information should be incorporated into facility baselines as controlled elements; and specify the level of formality that should be applied to activities that employ or impact these controlled elements. Evaluation categories include the following: radiological damage to workers; toxicological damage to workers; industrial safety; environmental damage; property damage; facility availability; cost effect; reputation; and commitments

  17. Strategies for denaturing the weapons-grade plutonium stockpile

    International Nuclear Information System (INIS)

    Buckner, M.R.; Parks, P.B.

    1992-10-01

    In the next few years, approximately 50 metric tons of weapons-grade plutonium and 150 metric tons of highly-enriched uranium (HEU) may be removed from nuclear weapons in the US and declared excess. These materials represent a significant energy resource that could substantially contribute to our national energy requirements. HEU can be used as fuel in naval reactors, or diluted with depleted uranium for use as fuel in commercial reactors. This paper proposes to use the weapons-grade plutonium as fuel in light water reactors. The first such reactor would demonstrate the dual objectives of producing electrical power and denaturing the plutonium to prevent use in nuclear weapons

  18. Nuclear law - Nuclear safety

    International Nuclear Information System (INIS)

    Pontier, Jean-Marie; Roux, Emmanuel; Leger, Marc; Deguergue, Maryse; Vallar, Christian; Pissaloux, Jean-Luc; Bernie-Boissard, Catherine; Thireau, Veronique; Takahashi, Nobuyuki; Spencer, Mary; Zhang, Li; Park, Kyun Sung; Artus, J.C.

    2012-01-01

    This book contains the contributions presented during a one-day seminar. The authors propose a framework for a legal approach to nuclear safety, a discussion of the 2009/71/EURATOM directive which establishes a European framework for nuclear safety in nuclear installations, a comment on nuclear safety and environmental governance, a discussion of the relationship between citizenship and nuclear, some thoughts about the Nuclear Safety Authority, an overview of the situation regarding the safety in nuclear waste burying, a comment on the Nome law with respect to electricity price and nuclear safety, a comment on the legal consequences of the Fukushima accident on nuclear safety in the Japanese law, a presentation of the USA nuclear regulation, an overview of nuclear safety in China, and a discussion of nuclear safety in the medical sector

  19. Homemade nuclear bomb syndrome

    International Nuclear Information System (INIS)

    Meyer, W.; Loyalka, S.K.; Nelson, W.E.; Williams, R.W.

    1977-01-01

    With the publication of Nuclear Theft: Risks and Safeguards by Willrich and Taylor, significant attention has been focused by the media and the public on the possibility of fissile materials being stolen by a terrorist organization and diverted to the actual building, or the threat of building, of a nuclear explosive device. The implication has been created that one or several relatively inexperienced individuals could obtain the materials necessary and fabricate a low-yield nuclear explosive. This article examines these contentions in some detail. The safeguards and use-denial methods presently used in the nuclear fuel cycle are considered and the difficulties they present in obtaining significant amounts of strategic nuclear materials are examined. The characteristics of reactor-grade plutonium are discussed, and the difficulties associated with the assembly of an efficient nuclear explosive device are outlined

  20. A low-grade extraskeletal osteosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Kyoji; Ito, Hiroki; Miyakoshi, Naohisa; Itoi, Eiji [Department of Orthopedic Surgery, Akita University School of Medicine, 1-1-1 Hondo, Akita 010-8543 (Japan); Sageshima, Masato [Department of Clinical Pathology, Akita University Hospital, 1-1-1 Hondo, Akita 010-8543 (Japan); Nishida, Jun [Department of Orthopedic Surgery, Iwate Medical School, 19-1 Uchimaru, Morioka 020-8505 (Japan)

    2003-03-01

    The case of a 35-year-old woman with low-grade extraskeletal osteosarcoma of the left leg is presented. Radiographs showed peripheral ossification of the lesion, suggesting myositis ossificans. Most of the tumor was composed of cartilage, and the cellularity and cell atypia of the proliferating chondrocytes were mild to moderate. In the periphery, bone formation with a relatively clear margin and proliferation of spindle cells with minimal nuclear atypia were observed. The average percentage of cells positive for MIB-1 was 9.0%. A diagnosis of low-grade extraskeletal osteosarcoma was made on the basis of these histologic findings. The clinical course 47 months after a wide excision was uneventful. (orig.)

  1. Inflated Grades, Enrollments & Budgets

    Directory of Open Access Journals (Sweden)

    J. E. Stone

    1995-06-01

    Full Text Available Reports of the past 13 years that call attention to deficient academic standards in American higher education are enumerated. Particular attention is given the Wingspread Group's recent An American Imperative: Higher Expectations for Higher Education. Low academic standards, grade inflation, and budgetary incentives for increased enrollment are analyzed and a call is made for research at the state level. Reported trends in achievement and GPAs are extrapolated to Tennessee and combined with local data to support the inference that 15% of the state's present day college graduates would not have earned a diploma by mid 1960s standards. A conspicuous lack of interest by public oversight bodies is noted despite a growing public awareness of low academic expectations and lenient grading and an implicit budgetary impact of over $100 million. Various academic policies and the dynamics of bureaucratic control are discussed in relationship to the maintenance of academic standards. The disincentives for challenging course requirements and responsible grading are examined, and the growing movement to address academic quality issues through better training and supervision of faculty are critiqued. Recommendations that would encourage renewed academic integrity and make learning outcomes visible to students, parents, employers, and the taxpaying public are offered and briefly discussed.

  2. TCGA_LowerGradeGliomas

    Science.gov (United States)

    TCGA researchers analyzed nearly 300 cases of diffuse low- and intermediate-grade gliomas, which together comprise lower-grade gliomas. LGGs occur mainly in adults and include astrocytomas, oligodendrogliomas and oligoastrocytomas.

  3. Let's End the Grading Game.

    Science.gov (United States)

    Edwards, Clifford H.; Edwards, Laurie

    1999-01-01

    Argues that grades have negative effects on learning and self-concept. States that while grading has a long tradition of sorting children for college entrance, there is limited evidence that grades serve a valid purpose. Argues that this practice should be abolished and an evaluation system established that provides a more valid estimate of…

  4. Four Steps in Grading Reform

    Science.gov (United States)

    Guskey, Thomas R.; Jung, Lee Ann

    2012-01-01

    The field of education is moving rapidly toward a standards-based approach to grading. School leaders have become increasingly aware of the tremendous variation that exists in grading practices, even among teachers of the same courses in the same department in the same school. Consequently, students' grades often have little relation to their…

  5. Discussion of QA grading for AP1000 NP plant

    International Nuclear Information System (INIS)

    Luo Shuiyun; Zhang Qingchuan

    2012-01-01

    The grading method of quality assurance for the following AP1000 project is presented based on the Westinghouse classification principle, referring to the classification method of the AP1000 self-reliance supporting project and considering the factors of classification, which can meet the requirements of domestic nuclear safety regulation and standard of the QA classification. (authors)

  6. TSUNAMI analysis of the applicability of proposed experiments to reactor-grade and weapons-grade mixed-oxide systems

    International Nuclear Information System (INIS)

    Rearden, Bradley T.; Hopper, Calvin M.; Elam, Karla R.

    2005-01-01

    The applicability of proposed critical experiments for the criticality code validation of a series of prototypic reactor-grade and weapons-grade mixed-oxide systems has been assessed with the TSUNAMI methodology from SCALE 5. The application systems were proposed by the Nuclear Energy Agency (NEA) Organization for Economic Cooperation and Development (OECD) Working Party on Nuclear Criticality Safety MOX Experimental Needs Working Group. Forty-eight application systems were conceived to envelope the range of conditions in processing and fabrication of reactor-grade and weapons-grade MOX fuel. The applicability of 303 existing critical benchmarks to each of the 48 applications was assessed, and validation coverage was found to be lacking for certain applications. Two series of proposed critical experiments were also considered in this analysis. The TSUNAMI analysis has revealed that both series of proposed experiments are applicable to numerous configurations of the reactor-grade and weapons-grade systems. A detailed assessment of which experiments were revealed by TSUNAMI to be most applicable to specific prototypic fuel processing systems has been performed. (author)

  7. The American nuclear Society's educational outreach programme

    International Nuclear Information System (INIS)

    Zacha, N.J.

    1994-01-01

    The American Nuclear Society has an extensive program of public educational outreach in the area of nuclear science and technology. A teacher workshop program provides up to five days of hands-on experiments, lectures, field trips, and lesson plan development for grades 6-12 educators. Curriculum materials have been developed for students in grades kindergarten through grade 12. A textbook review effort provides reviews of existing textbooks as well as draft manuscripts and textbook proposals, to ensure that the information covered on nuclear science and technology is accurate and scientifically sound

  8. Uranium production from low grade Swedish shale

    International Nuclear Information System (INIS)

    Carlsson, O.

    1977-01-01

    In view of the present nuclear programmes a steep increase in uranium demand is foreseen which will pose serious problems for the uranium industry. The annual additions to uranium ore reserves must almost triple within the next 15 years in order to support the required production rates. Although there are good prospects for the discovery of further conventional deposits of uranium there is a growing interest in low grade uranium deposits. Large quantities of uranium exist in black shales, phosphates, granites, sea water and other unconventional sources. There are however factors which limit the utilization of these low grade materials. These factors include the extraction costs, the environmental constrains on mining and milling of huge amounts of ore, the development of technologies for the beneficiation of uranium and, in the case of very low grade materials, the energy balance. The availability of by-product uranium is limited by the production rate of the main product. The limitations differ very much according to types of ores, mining and milling methods and the surroundings. As an illustration a description is given of the Swedish Ranstad uranium shale project, its potential, constraints and technical solutions

  9. Functionally Graded Materials Database

    Science.gov (United States)

    Kisara, Katsuto; Konno, Tomomi; Niino, Masayuki

    2008-02-01

    Functionally Graded Materials Database (hereinafter referred to as FGMs Database) was open to the society via Internet in October 2002, and since then it has been managed by the Japan Aerospace Exploration Agency (JAXA). As of October 2006, the database includes 1,703 research information entries with 2,429 researchers data, 509 institution data and so on. Reading materials such as "Applicability of FGMs Technology to Space Plane" and "FGMs Application to Space Solar Power System (SSPS)" were prepared in FY 2004 and 2005, respectively. The English version of "FGMs Application to Space Solar Power System (SSPS)" is now under preparation. This present paper explains the FGMs Database, describing the research information data, the sitemap and how to use it. From the access analysis, user access results and users' interests are discussed.

  10. The Implications of Grade Inflation

    DEFF Research Database (Denmark)

    Smith, David E.; Fleisher, Steven

    2011-01-01

    The authors review current and past practices of the grade inflation controversy and present ways to return to each institution’s established grading guidelines. Students are graded based on knowledge gathered. Certain faculty members use thorough evaluative methods, such as written and oral pres...... have been profiled in the news. The model is provided to ensure that degree candidates are academic experts in their field, having earned the credential through rigorous study....

  11. Nuclear Medicine

    Science.gov (United States)

    ... Parents/Teachers Resource Links for Students Glossary Nuclear Medicine What is nuclear medicine? What are radioactive tracers? ... funded researchers advancing nuclear medicine? What is nuclear medicine? Nuclear medicine is a medical specialty that uses ...

  12. Nuclear safety. Seguranca nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Aveline, A [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Inst. de Fisica

    1981-01-01

    What is nuclear safety Is there any technical way to reduce risks Is it possible to put them at reasonable levels Are there competitiveness and economic reliability to employ the nuclear energy by means of safety technics Looking for answers to these questions the author describes the sources of potential risks to nuclear reactors and tries to apply the answers to the Brazilian Nuclear Programme. (author).

  13. Transport of nuclear materials

    International Nuclear Information System (INIS)

    Anon.

    2002-01-01

    During november and december 2001, 2 events concerning nuclear transport were reported and classified on the first grade (grade 1) of the INES scale. The first event concerns a hole in a transport cask of contaminated tools. The hole seems to have been made by the fork of a handling equipment. The second event concerns the loss of a parcel containing a technetium generator, this generator represented an activity of about 141 G Becquerel of 99 Mo the day it left the premises of CIS-bio in Saclay. (A.C.)

  14. Invisible nuclear; converting nuclear

    International Nuclear Information System (INIS)

    Park, Jongmoon

    1993-03-01

    This book consists of 14 chapters which are CNN era and big science, from East and West to North and South, illusory nuclear strategy, UN and nuclear arms reduction, management of armaments, advent of petroleum period, the track of nuclear power generation, view of energy, internationalization of environment, the war over water in the Middle East, influence of radiation and an isotope technology transfer and transfer armament into civilian industry, the end of nuclear period and the nuclear Nonproliferation, national scientific and technological power and political organ and executive organ.

  15. Practicing Good Habits, Grade 4.

    Science.gov (United States)

    Van Cong Lau; And Others

    This illustrated textbook was designed for teaching civics and values to fourth grade students in Vietnam. It is divided into six chapters: (1) At School (recapitulation of the grade three program, friendship, respect for the teacher, team work, discipline, honor); (2) In the Street: Traffic Regulations; (3) At Home (the extended family spirit,…

  16. Graded geometry and Poisson reduction

    OpenAIRE

    Cattaneo, A S; Zambon, M

    2009-01-01

    The main result of [2] extends the Marsden-Ratiu reduction theorem [4] in Poisson geometry, and is proven by means of graded geometry. In this note we provide the background material about graded geometry necessary for the proof in [2]. Further, we provide an alternative algebraic proof for the main result. ©2009 American Institute of Physics

  17. Compositionally Graded Multilayer Ceramic Capacitors.

    Science.gov (United States)

    Song, Hyun-Cheol; Zhou, Jie E; Maurya, Deepam; Yan, Yongke; Wang, Yu U; Priya, Shashank

    2017-09-27

    Multilayer ceramic capacitors (MLCC) are widely used in consumer electronics. Here, we provide a transformative method for achieving high dielectric response and tunability over a wide temperature range through design of compositionally graded multilayer (CGML) architecture. Compositionally graded MLCCs were found to exhibit enhanced dielectric tunability (70%) along with small dielectric losses (filters and power converters.

  18. Analysis of india and Pakistan's nuclear capacity

    International Nuclear Information System (INIS)

    Li Zhimin

    1999-07-01

    The development and capacity of both India and Pakistan's nuclear weapons are described in production of weapon-grade materials, nuclear testing, weaponization engineering and delivery systems. India is capable of designing and manufacturing both small yield tactic nuclear weapons and big yield strategic ones and also possesses the technique to design and manufacture H-bombs. Weapon-grade plutonium constitutes the primary fission material for India's nuclear weapon and it has plutonium enough to make 70 to 100 nuclear weapons. India can also produce some tritium. India has already possessed delivery systems but it has not yet mounted nuclear warheads on its ballistic missiles even though its missiles, which India has already owned or is under development, have the ability to carry nuclear warheads. Pakistan also has the ability to make both tactic nuclear weapons and strategic ones. With its weapon-grade uranium, 20 to 30 nuclear weapons can be made. Besides the uranium production facility. Pakistan also has the facility to produce tritium. It is supposed that Pakistan has the ability to carry nuclear weapons with airplane, but it has a long way to go if it wants to mount nuclear weapon, especially bit yield ones, on its own missile. As a whole, India's nuclear force is stronger than Pakistan's, and its development far more advanced than Pakistan's

  19. The long-term nuclear explosives predicament

    International Nuclear Information System (INIS)

    Swahn, J.

    1992-01-01

    A scenario is described, where the production of new military fissile materials is halted and where civil nuclear power is phased out in a 'no-new orders' case. It is found that approximately 1100 tonnes of weapons-grade uranium, 233 tonnes of weapons-grade plutonium and 3795 tonnes of reactor-grade plutonium have to be finally disposed of as nuclear waste. This material could be used for the construction of over 1 million nuclear explosives. Reactor-grade plutonium is found to be easier to extract from spent nuclear fuel with time and some physical characteristics important for the construction of nuclear explosives are improved. Alternative methods for disposal of the fissile material that will avoid the long-term nuclear explosives predicament are examined. Among these methods are dilution, denaturing or transmutation of the fissile material and options for practicably irrecoverable disposal in deep boreholes, on the sea-bed, and in space. It is found that the deep boreholes method for disposal should be the primary alternative to be examined further. This method can be combined with an effort to 'forget' where the material was put. Included in the thesis is also an evaluation of the possibilities of controlling the limited civil nuclear activities in a post-nuclear world. Some surveillance technologies for a post-nuclear world are described, including satellite surveillance. In a review part of the thesis, methods for the production of fissile material for nuclear explosives are described, the technological basis for the construction of nuclear weapons is examined, including use of reactor-grade plutonium for such purposes; also plans for the disposal of spent fuel from civil nuclear power reactors and for the handling of the fissile material from dismantled warheads is described. The Swedish plan for the handling and disposal of spent nuclear fuel is described in detail. (490 refs., 66 figs., 27 tabs.)

  20. Nuclear power. [Contains glossary

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, W.C.

    1983-01-01

    Lay language brings an understanding of nuclear technology and nuclear politics to the non-specialist reader. The author notes that there has been little change in the technology during the four decades of the nuclear age, but mankind has still to learn how to live with it. Part One explains how reactors work, identifies different reactor types, and describes the fuel cycle. Part two follows research developments during the pre-Manhatten Project days, the war effort, and the decision to pursue commercial nuclear power. He traces the development of policies to secure fission materials and international efforts to prevent the proliferation of weapons grade material and the safe handling of radioactive wastes on a global as well as national scale. There are four appendices, including an annotated reference to other publications. 9 figures.

  1. Nuclear power generation and nuclear fuel

    International Nuclear Information System (INIS)

    Okajima, Yasujiro

    1985-01-01

    As of June 30, 1984, in 25 countries, 311 nuclear power plants of about 209 million kW were in operation. In Japan, 27 plants of about 19 million kW were in operation, and Japan ranks fourth in the world. The present state of nuclear power generation and nuclear fuel cycle is explained. The total uranium resources in the free world which can be mined at the cost below $130/kgU are about 3.67 million t, and it was estimated that the demand up to about 2015 would be able to be met. But it is considered also that the demand and supply of uranium in the world may become tight at the end of 1980s. The supply of uranium to Japan is ensured up to about 1995, and the yearly supply of 3000 st U 3 O 8 is expected in the latter half of 1990s. The refining, conversion and enrichment of uranium are described. In Japan, a pilot enrichment plant consisting of 7000 centrifuges has the capacity of about 50 t SWU/year. UO 2 fuel assemblies for LWRs, the working of Zircaloy, the fabrication of fuel assemblies, the quality assurance of nuclear fuel, the behavior of UO 2 fuel, the grading-up of LWRs and nuclear fuel, and the nuclear fuel business in Japan are reported. The reprocessing of spent fuel and plutonium fuel are described. (Kako, I.)

  2. Nuclear industry - challenges in chemical engineering

    International Nuclear Information System (INIS)

    Sen, S.; Sunder Rajan, N.S.; Balu, K.; Garg, R.K.; Murthy, L.G.K.; Ramani, M.P.S.; Rao, M.K.; Sadhukhan, H.K.; Venkat Raj, V.

    1978-01-01

    As chemical engineering processes and operations are closely involved in many areas of nuclear industry, the chemical engineer has a vital role to play in its growth and development. An account of the major achievements of the Indian chemical engineers in this field is given with view of impressing upon the faculty members of the Indian universities the need for taking appropriate steps to prepare chemical engineers suitable for nuclear industry. Some of the major achievements of the Indian chemical engineers in this field are : (1) separation of useful minerals from beach sand, (2) preparation of thorium nitrate of nuclear purity from monazite, (3) processing of zircon sand to obtain nuclear grade zirconium and its separation from hafnium to obtain zirconium metal sponge, (4) recovery of uranium from copper tailings, (5) economic recovery of nuclear grade uranium from low grade uranium ores found in India, (6) fuel reprocessing, (7) chemical processing of both low and high level radioactive wastes. (M.G.B.)

  3. Effect of Quantitative Nuclear Image Features on Recurrence of Ductal Carcinoma In Situ (DCIS of the Breast

    Directory of Open Access Journals (Sweden)

    Judith-Anne W. Chapman

    2008-01-01

    Full Text Available Background: Nuclear grade has been associated with breast DCIS recurrence and progression to invasive carcinoma; however, our previous study of a cohort of patients with breast DCIS did not find such an association with outcome. Fifty percent of patients had heterogeneous DCIS with more than one nuclear grade. The aim of the current study was to investigate the effect of quantitative nuclear features assessed with digital image analysis on ipsilateral DCIS recurrence.Methods: Hematoxylin and eosin stained slides for a cohort of 80 patients with primary breast DCIS were reviewed and two fields with representative grade (or grades were identified by a Pathologist and simultaneously used for acquisition of digital images for each field. Van Nuys worst nuclear grade was assigned, as was predominant grade, and heterogeneous grading when present. Patients were grouped by heterogeneity of their nuclear grade: Group A: nuclear grade 1 only, nuclear grades 1 and 2, or nuclear grade 2 only (32 patients, Group B: nuclear grades 1, 2 and 3, or nuclear grades 2 and 3 (31 patients, Group 3: nuclear grade 3 only (17 patients. Nuclear fi ne structure was assessed by software which captured thirty-nine nuclear feature values describing nuclear morphometry, densitometry, and texture. Step-wise forward Cox regressions were performed with previous clinical and pathologic factors, and the new image analysis features.Results: Duplicate measurements were similar for 89.7% to 97.4% of assessed image features. The rate of correct classification of nuclear grading with digital image analysis features was similar in the two fields, and pooled assessment across both fields. In the pooled assessment, a discriminant function with one nuclear morphometric and one texture feature was significantly (p = 0.001 associated with nuclear grading, and provided correct jackknifed classification of a patient’s nuclear grade for Group A (78.1%, Group B (48.4%, and Group C (70.6%. The

  4. Effect of Grade Retention in First Grade on Psychosocial Outcomes

    OpenAIRE

    Wu, Wei; West, Stephen G.; Hughes, Jan N.

    2010-01-01

    In a 4-year longitudinal study, the authors investigated effects of retention in first grade on children’s externalizing and internalizing behaviors; social acceptance; and behavioral, cognitive, and affective engagement. From a large multiethnic sample (n = 784) of children below the median on literacy at school entrance, 124 retained children were matched with 251 promoted children on the basis of propensity scores (probability of being retained in first grade estimated from 72 baseline var...

  5. [Nuclear theory

    International Nuclear Information System (INIS)

    Haxton, W.

    1990-01-01

    This report discusses research in nuclear physics. Topics covered in this paper are: symmetry principles; nuclear astrophysics; nuclear structure; quark-gluon plasma; quantum chromodynamics; symmetry breaking; nuclear deformation; and cold fusion

  6. Actinide recovery from waste and low-grade sources

    International Nuclear Information System (INIS)

    Navratil, J.D.; Schulz, W.W.

    1982-01-01

    Actinide and nuclear fuel cycle operations generate a variety of process waste streams. New methods are needed to remove and recover actinides. More interest is also being expressed in recovering uranium from oceans, phosphoric acid, and other low grade sources. To meet the need for an up-to-date status report in the area of actinide recovery from waste and low grade sources, these papers were brought together. The papers provide an authoritative, in-depth coverage of an important area of nuclear and industrial and engineering chemistry which cover the following topics: uranium recovery from oceans and phosphoric acid; recovery of actinides from solids and liquid wastes; plutonium scrap recovery technology; and other new developments in actinide recovery processes

  7. Nuclear topics

    International Nuclear Information System (INIS)

    Lukner, C.

    1982-07-01

    The pamphlet touches on all aspects of nuclear energy, from the world energy demands and consumption, the energy program of the Federal Government, nuclear power plants in the world, nuclear fusion, nuclear liability up to the nuclear fuel cycle and the shutdown of nuclear power plants. (HSCH) [de

  8. Gender discrimination in exam grading?

    DEFF Research Database (Denmark)

    Rangvid, Beatrice Schindler

    2018-01-01

    Girls, on average, obtain higher test scores in school than boys, and recent research suggests that part of this difference may be due to discrimination against boys in grading. This bias is consequential if admission to subsequent education programs is based on exam scores. This study assesses t...... tendencies are in accordance with statistical discrimination as a mechanism for grading bias in essay writing and with gender-stereotyped beliefs of math being a male domain....... are scored twice (blind and non-blind). Both strategies use difference-in-differences methods. Although imprecisely estimated, the point estimates indicate a blind grading advantage for boys in essay writing of approximately 5-8% SD, corresponding to 9-15% of the gender gap in essay exam grades. The effect...

  9. Progressive problems higher grade physics

    CERN Document Server

    Kennedy, William

    2001-01-01

    This book fully covers all three Units studied in Scotland's Higher Grade Physics course, providing a systematic array of problems (from the simplest to the most difficult) to lead variously abled pupils to examination success.

  10. Grade 6 Science Curriculum Specifications.

    Science.gov (United States)

    Alberta Dept. of Education, Edmonton. Curriculum Branch.

    This material describes curriculum specifications for grade 6 science in Alberta. Emphases recommended are: (1) process skills (50%); (2) psychomotor skills (10%); (3) attitudes (10%); and (4) subject matter (30%). Priorities within each category are identified. (YP)

  11. Improving GRADE evidence tables part 2

    DEFF Research Database (Denmark)

    Langendam, Miranda; Carrasco-Labra, Alonso; Santesso, Nancy

    2016-01-01

    OBJECTIVES: The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) working group has developed GRADE evidence profiles (EP) and summary of findings (SoF) tables to present evidence summaries in systematic reviews, clinical guidelines, and health technology assessments. Exp...

  12. Nuclear power and nuclear weapons

    International Nuclear Information System (INIS)

    Vaughen, V.C.A.

    1983-01-01

    The proliferation of nuclear weapons and the expanded use of nuclear energy for the production of electricity and other peaceful uses are compared. The difference in technologies associated with nuclear weapons and nuclear power plants are described

  13. Type 1 IGF Receptor Localization in Paediatric Gliomas: Significant Association with WHO Grading and Clinical Outcome.

    Science.gov (United States)

    Clément, Florencia; Martin, Ayelen; Venara, Marcela; de Luján Calcagno, Maria; Mathó, Cecilia; Maglio, Silvana; Lombardi, Mercedes García; Bergadá, Ignacio; Pennisi, Patricia A

    2018-06-01

    Nuclear localization of insulin-like growth factor receptor type 1 (IGF-1R) has been described as adverse prognostic factor in some cancers. We studied the expression and localization of IGF-1R in paediatric patients with gliomas, as well as its association with World Health Organization (WHO) grading and survival. We conducted a single cohort, prospective study of paediatric patients with gliomas. Samples were taken at the time of the initial surgery; IGF-1R expression and localization were characterized by immunohistochemistry (IHC), subcellular fractionation and western blotting. Tumours (47/53) showed positive staining for IGF-1R by IHC. IGF-1R nuclear labelling was observed in 10/47 cases. IGF-1R staining was mostly non-nuclear in low-grade tumours, while IGF-1R nuclear labelling was predominant in high-grade gliomas (p = 0.0001). Survival was significantly longer in patients with gliomas having non-nuclear IGF-1R localization than in patients with nuclear IGF-1R tumours (p = 0.016). In gliomas, IGF-1R nuclear localization was significantly associated with both high-grade tumours and increased risk of death. Based on a prospective design, we provide evidence of a potential usefulness of intracellular localization of IGF-1R as prognostic factor in paediatric patients with gliomas.

  14. Commercial Grade Item (CGI) dedication - on complex electronic equipment

    International Nuclear Information System (INIS)

    Sohn, Kwang Young; Kim, Joong Han; Koo, In Soo; Lee, Sang Yong

    2008-01-01

    In future more complicated IT-based hardware and software is supposed to used in the safety-grade systems in nuclear power plants. Also there are the efforts to establish the criteria for CGI dedications in NRC and CEC dedication in other standard organizations. The highly complicated components, i.e. CEC should be dedication plans. Thus work to be done in later is to prepare the strategies, plans, guide and procedures that is more specific for CEC dedication

  15. Cracks in functionally graded materials

    International Nuclear Information System (INIS)

    Bahr, H.-A.; Balke, H.; Fett, T.; Hofinger, I.; Kirchhoff, G.; Munz, D.; Neubrand, A.; Semenov, A.S.; Weiss, H.-J.; Yang, Y.Y.

    2003-01-01

    The weight function method is described to analyze the crack growth behavior in functionally graded materials and in particular materials with a rising crack growth resistance curve. Further, failure of graded thermal barrier coatings (TBCs) under cyclic surface heating by laser irradiation is modeled on the basis of fracture mechanics. The damage of both graded and non-graded TBCs is found to develop in several distinct stages: vertical cracking→delamination→blistering→spalling. This sequence can be understood as an effect of progressive shrinkage due to sintering and high-temperature creep during thermal cycling, which increases the energy-release rate for vertical cracks which subsequently turn into delamination cracks. The results of finite element modeling, taking into account the TBC damage mechanisms, are compatible with experimental data. An increase of interface fracture toughness due to grading and a decrease due to ageing have been measured in a four-point bending test modified by a stiffening layer. Correlation with the damage observed in cyclic heating is discussed. It is explained in which way grading is able to reduce the damage

  16. Graded/Gradient Porous Biomaterials

    Directory of Open Access Journals (Sweden)

    Xigeng Miao

    2009-12-01

    Full Text Available Biomaterials include bioceramics, biometals, biopolymers and biocomposites and they play important roles in the replacement and regeneration of human tissues. However, dense bioceramics and dense biometals pose the problem of stress shielding due to their high Young’s moduli compared to those of bones. On the other hand, porous biomaterials exhibit the potential of bone ingrowth, which will depend on porous parameters such as pore size, pore interconnectivity, and porosity. Unfortunately, a highly porous biomaterial results in poor mechanical properties. To optimise the mechanical and the biological properties, porous biomaterials with graded/gradient porosity, pores size, and/or composition have been developed. Graded/gradient porous biomaterials have many advantages over graded/gradient dense biomaterials and uniform or homogenous porous biomaterials. The internal pore surfaces of graded/gradient porous biomaterials can be modified with organic, inorganic, or biological coatings and the internal pores themselves can also be filled with biocompatible and biodegradable materials or living cells. However, graded/gradient porous biomaterials are generally more difficult to fabricate than uniform or homogenous porous biomaterials. With the development of cost-effective processing techniques, graded/gradient porous biomaterials can find wide applications in bone defect filling, implant fixation, bone replacement, drug delivery, and tissue engineering.

  17. The Utility of Phosphohistone H3 in Breast Cancer Grading.

    Science.gov (United States)

    Cui, Xiaoyan; Harada, Shuko; Shen, Dejun; Siegal, Gene P; Wei, Shi

    2015-01-01

    The commonly used Nottingham Grading System in breast cancer takes into consideration the presence of tubular formation, nuclear pleomorphism, and the mitotic index (MI), among which the latter has been shown to be the most powerful prognostic factor. In practice, histologic grading is highly subjective, with only moderate interobserver reproducibility. Phosphorylation of histone H3 has been demonstrated to be a specific event in the mitotic phase, and is negligible during interphase. In this study, we evaluated the efficacy of Phosphohistone H3 (PHH3) in the breast cancer grading of 97 consecutive biopsy specimens. PHH3 antibodies clearly revealed discrete, strong nuclear immunoreactivity in mitotically active cells even under low magnification. The PHH3 MI showed a significant correlation with that derived by hematoxylin and eosin (H&E) staining as well as the Ki-67 proliferation index. Further, the pairwise κ-value of the MI was significantly increased, and the pairwise agreement was also markedly improved by PHH3 immunostaining, although a significant proportion of breast cancer cases were upgraded by use of the PHH3 MI. Our data showed that PHH3 provided a more sensitive and accurate MI with less interobserver variability when compared with conventional H&E staining, thus emphasizing its potentially increased value in practice. Reconsideration of breast cancer grading with integration of PHH3 should be considered if it continues to demonstrate superiorly to traditional H&E staining.

  18. Hardwood log grades and lumber grade yields for factory lumber logs

    Science.gov (United States)

    Leland F. Hanks; Glenn L. Gammon; Robert L. Brisbin; Everette D. Rast

    1980-01-01

    The USDA Forest Service Standard Grades for Hardwood Factory Lumber Logs are described, and lumber grade yields for 16 species and 2 species groups are presented by log grade and log diameter. The grades enable foresters, log buyers, and log sellers to select and grade those log suitable for conversion into standard factory grade lumber. By using the apropriate lumber...

  19. 7 CFR 810.2204 - Grades and grade requirements for wheat.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Grades and grade requirements for wheat. 810.2204... OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Wheat Principles Governing the Application of Standards § 810.2204 Grades and grade requirements for wheat. (a) Grades and grade requirements...

  20. Material development for India's nuclear power programme

    Indian Academy of Sciences (India)

    rials with emphasis on development of fabrication routes of zirconium alloys for .... nuclear power programme, which envisages design and construction of thermal breeder ... Production of Hf-free nuclear grade zirconium ..... Later on for pressure tubes specified limit for hydrogen content in the as manufactured condition.

  1. Nuclear rights - nuclear wrongs

    Energy Technology Data Exchange (ETDEWEB)

    Paul, E.F.; Miller, F.D.; Paul, J.; Ahrens, J.

    1986-01-01

    This book contains 11 selections. The titles are: Three Ways to Kill Innocent Bystanders: Some Conundrums Concerning the Morality of War; The International Defense of Liberty; Two Concepts of Deterrence; Nuclear Deterrence and Arms Control; Ethical Issues for the 1980s; The Moral Status of Nuclear Deterrent Threats; Optimal Deterrence; Morality and Paradoxical Deterrence; Immoral Risks: A Deontological Critique of Nuclear Deterrence; No War Without Dictatorship, No Peace Without Democracy: Foreign Policy as Domestic Politics; Marxism-Leninism and its Strategic Implications for the United States; Tocqueveille War.

  2. Nuclear moments

    CERN Document Server

    Kopferman, H; Massey, H S W

    1958-01-01

    Nuclear Moments focuses on the processes, methodologies, reactions, and transformations of molecules and atoms, including magnetic resonance and nuclear moments. The book first offers information on nuclear moments in free atoms and molecules, including theoretical foundations of hyperfine structure, isotope shift, spectra of diatomic molecules, and vector model of molecules. The manuscript then takes a look at nuclear moments in liquids and crystals. Discussions focus on nuclear paramagnetic and magnetic resonance and nuclear quadrupole resonance. The text discusses nuclear moments and nucl

  3. Boosting nuclear fuels

    International Nuclear Information System (INIS)

    Demarthon, F.; Donnars, O.; Dupuy-Maury, F.

    2002-01-01

    This dossier gives a broad overview of the present day status of the nuclear fuel cycle in France: 1 - the revival of nuclear power as a solution to the global warming and to the increase of worldwide energy needs; 2 - the security of uranium supplies thanks to the reuse of weapon grade highly enriched uranium; 3 - the fabrication of nuclear fuels from the mining extraction to the enrichment processes, the fabrication of fuel pellets and the assembly of fuel rods; 4 - the new composition of present day fuels (UO x and chromium-doped pellets); 5 - the consumption of plutonium stocks and the Corail and Apa fuel assemblies for the reduction of plutonium stocks and the preservation of uranium resources. (J.S.)

  4. Strand V: Education for Survival. First Aid and Survival Education. Health Curriculum Materials Grades 10-12.

    Science.gov (United States)

    New York State Education Dept., Albany. Bureau of Secondary Curriculum Development.

    GRADES OR AGES: Grades 10-12. SUBJECT MATTER: First aid and survival education. ORGANIZATION AND PHYSICAL APPEARANCE: The guide is divided into six sections: transportation of the injured, automobile accidents, conditions resulting from nuclear explosion, chemical warfare, natural catastrophes, and psychological first aid. The publication format…

  5. Using NJOY99 and MCNP4B2 to Estimate the Radiation Damage Displacements per Atom per Second in Steel Within the Boiling Water Reactor Core Shroud and Vessel Wall from Reactor-Grade Mixed-Oxide/Uranium Oxide Fuel for the Nuclear Power Plant at Laguna Verde, Veracruz, Mexico

    International Nuclear Information System (INIS)

    Vickers, Lisa

    2003-01-01

    The government of Mexico has expressed interest in utilizing the Laguna Verde boiling water reactor (BWR) nuclear power plant for the disposition of reprocessed spent uranium oxide (UOX) fuel in the form of reactor-grade mixed-oxide (MOX) fuel. MOX fuel would replace spent UOX fuel as a fraction in the core from 18 to 30% depending on the fuel loading cycle. MOX fuel is expected to increase the neutron fluence, flux, fuel centerline temperature, reactor core pressure, and yield higher energy neutrons.There is concern that a core with a fraction of MOX fuel (i.e., increased 239 Pu wt%) would increase the radiation damage displacements per atom per second (dpa-s -1 ) in steel within the core shroud and vessel wall as compared to only conventional, enriched UOX fuel in the core. The evaluation of radiation damage within the core shroud and vessel wall is a concern because of the potentially adverse affect to personnel and public safety, environment, and operating life of the reactor.The primary uniqueness of this paper is the computation of radiation damage (dpa-s -1 ) using NJOY99-processed cross sections for steel within the core shroud and vessel wall. Specifically, the unique radiation damage results are several orders of magnitude greater than results of previous works. In addition, the conclusion of this paper was that the addition of the maximum fraction of one-third MOX fuel to the LV1 BWR core did significantly increase the radiation damage in steel within the core shroud and vessel wall such that without mitigation of radiation damage by periodic thermal annealing or reduction in operating parameters such as neutron fluence, core temperature, and pressure, it posed a potentially adverse affect to the personnel and public safety, environment, and operating life of the reactor

  6. Energy Balance of Nuclear Power Generation. Life Cycle Analyses of Nuclear Power

    International Nuclear Information System (INIS)

    Wallner, A.; Wenisch, A.; Baumann, M.; Renner, S.

    2011-01-01

    The accident at the Japanese nuclear power plant Fukushima in March 2011 triggered a debate about phasing out nuclear energy and the safety of nuclear power plants. Several states are preparing to end nuclear power generation. At the same time the operational life time of many nuclear power plants is reaching its end. Governments and utilities now need to take a decision to replace old nuclear power plants or to use other energy sources. In particular the requirement of reducing greenhouse gas emissions (GHG) is used as an argument for a higher share of nuclear energy. To assess the contribution of nuclear power to climate protection, the complete life cycle needs to be taken into account. Some process steps are connected to high CO2 emissions due to the energy used. While the processes before and after conventional fossil-fuel power stations can contribute up to 25% of direct GHG emission, it is up to 90 % for nuclear power (Weisser 2007). This report aims to produce information about the energy balance of nuclear energy production during its life cycle. The following key issues were examined: How will the forecasted decreasing uranium ore grades influence energy intensity and greenhouse emissions and from which ore grade on will no energy be gained anymore? In which range can nuclear energy deliver excess energy and how high are greenhouse gas emissions? Which factors including ore grade have the strongest impact on excess energy? (author)

  7. Conversion of non-nuclear grade feedstock to UF4

    International Nuclear Information System (INIS)

    Ponelis, A.A.; Slabber, M.N.; Zimmer, C.H.E.

    1987-01-01

    The South African Conversion route is based on the direct feed of ammonium di-uranate produced by any one of a number of different mines. The physical and chemical characteristics of the feedstock can thus vary considerably and influence the conversion rate as well as the final UF 6 product purity. The UF 4 conversion reactor is a Moving Bed Reactor (MBR) with countercurrent flow of the reacting gas phases. Initial problems to continuously operate the MBR were mostly concerned with the physical nature of the UO 3 feed particles. Different approaches to eventually obtain a successful MBR are discussed. Besides obtaining UO 3 feed particles with certain physical attributes, the chemical impurities also have an effect on the operability of the MBR. The influence of the feedstock variables on the reduction and hydrofluorination rates after calcining has largely been determined from laboratory and pilot studies. The effect of chemical impurities such as sodium and potassium on the sinterability of the reacting particles and therefore the optimum temperature range in the MBR is also discussed. Confirmation of the effect of sodium and potassium impurities on the conversion rate has been obtained from large scale reactor operation. (author)

  8. Management of super-grade plutonium in spent nuclear fuel

    International Nuclear Information System (INIS)

    McFarlane, H. F.; Benedict, R. W.

    2000-01-01

    This paper examines the security and safeguards implications of potential management options for DOE's sodium-bonded blanket fuel from the EBR-II and the Fermi-1 fast reactors. The EBR-II fuel appears to be unsuitable for the packaging alternative because of DOE's current safeguards requirements for plutonium. Emerging DOE requirements, National Academy of Sciences recommendations, draft waste acceptance requirements for Yucca Mountain and IAEA requirements for similar fuel also emphasize the importance of safeguards in spent fuel management. Electrometallurgical treatment would be acceptable for both fuel types. Meeting the known requirements for safeguards and security could potentially add more than $200M in cost to the packaging option for the EBR-II fuel

  9. Spectrographic determination of lithium in nuclear grade calcium

    International Nuclear Information System (INIS)

    Artaud, J.; Cittanova, J.

    1957-01-01

    A method is described for the spectrographic determination of lithium in calcium. The samples are converted directly to CaCO 3 . A method of fractional distillation in the arc, using KCl as carrier, makes it possible to detect and measure the Li content to 0,1 ppm. (author) [fr

  10. Below Grade Assessment of Spent Nuclear Fuel Cask Transport Route

    International Nuclear Information System (INIS)

    CHENAULT, D.M.

    1999-01-01

    The report provides an assessment of the route for the SNF Fuel transport system from the K Basins to the CVDF and to the CSB. Results include the identification of any underground structures or utilities traveled over by the transport, the overburden depths for all locations identified, evaluation of the loading conditions, and determination of the effects of the loads on the structures and utilities

  11. Standard specification for nuclear-grade aluminum oxide pellets

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This specification applies to pellets of aluminum oxide that may be ultimately used in a reactor core, for example, as filler or spacers within fuel, burnable poison, or control rods. In order to distinguish between the subject pellets and “burnable poison” pellets, it is established that the subject pellets are not intended to be used as neutron-absorbing material. 1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

  12. Functionally Graded Mo sintered steels

    Directory of Open Access Journals (Sweden)

    Manuel Cisneros-Belmonte

    2016-12-01

    Full Text Available Functionally graded materials (FGM, the multi-materials, strive to satisfy the numerous requirements demanded of parts in a given combination of compositions and microstructures. The required material compatibility lead the manufacturing process and the achieving of an interface, not always diffuse. Powder metallurgy is one of the techniques used in manufacturing functionally graded materials, in particular the compaction matrix of the possible techniques for forming these materials. In this paper, a process of forming a functionally graded steel based on the use of a high molybdenum steel with cooper and other steel with copper, without molybdenum, is proposed with the aim of concentrating this element to the surface of the workpiece, increasing the mechanical strength. The study is completed with the evaluation of physical properties (density and porosity distribution, mechanical properties (hardness, tensile strength and elongation and microstructural analysis by optical and scanning electron microscopy.

  13. 7 CFR 51.304 - Combination grades.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... Standards for Grades of Apples Grades § 51.304 Combination grades. (a) Combinations of the above grades may...

  14. On-Demand Grades: The Effect of Online Grade Book Access on Student Mastery and Performance Goal Orientations, Grade Orientation, Academic Self Efficacy, and Grades

    Science.gov (United States)

    Seldow, Adam Lowell

    2010-01-01

    With the widespread growth of broadband Internet access, teachers, and in many cases, schools and school districts are transitioning from traditional paper-based grade books to student accessible online (Web-based) grade books. Online grade books offer students 24/7, on demand access to grades and various other student data, and have the potential…

  15. Defence in depth by 'Leittechnique' systems with graded intelligence

    International Nuclear Information System (INIS)

    Aleite, W.

    1983-01-01

    In the past, only two types of nuclear power plant instrumentation and control systems were in use in the Federal Republic of Germany (FRG): safety systems and operational systems. Present nuclear power plant 'Leittechnique' systems in the FRG have been expanded from this 'black-and-white' status to multiple-grade systems with respect to safety, qualification requirements and intelligence. The extensive experience of the past has encouraged the rule-making committees - representing all parties working in the nuclear field - to differentiate between the protection limitations and condition limitations of the reactor protection system on one hand and the information systems (including the accident monitoring and alarm system) of different safety importance on the other, assuming additional extensive application of non-safety-grade operational Leittechnique systems. These definitions of categories are in accordance with international practice and enable designers to apply 'echelons of defence', composed of equipment of all categories, in accordance with 'defence-in-depth' concepts. They also simplify the introduction of computerized equipment, especially in the lower safety categories. Status, background and reasons of the introduction, as well as typical defence-in-depth modes, of the first running Leittechnique system of this kind (in the Grafenrheinfeld nuclear power plant) and especially their different tasks in disturbance handling are described. The international situation and future developments are briefly characterized. (author)

  16. Functionally Graded Material: An overview

    CSIR Research Space (South Africa)

    Mahamood, RM

    2012-07-01

    Full Text Available -3146. [50] X. Jin, L. Wu, L. Guo, H. Yu, and Y. Sun, ?Experimental investigation of the mixed-mode crack propagation in ZrO2/NiCr functionally graded materials,? Engineering Fracture Mechanics, vol. 76(12), (2009), pp. 1800-1810. [51] Z. Cheng, D. Gao... by stable crack growth,? Engineering Fracture Mechanics, vol.72(15), (2005), pp. 2359-2372. [47] Z.-H. Jin, and R.H. Dodds Jr, ?Crack growth resistance behavior of a functionally graded material: computational studies,? Engineering Fracture Mechanics...

  17. On the union of graded prime ideals

    Directory of Open Access Journals (Sweden)

    Uregen Rabia Nagehan

    2016-01-01

    Full Text Available In this paper we investigate graded compactly packed rings, which is defined as; if any graded ideal I of R is contained in the union of a family of graded prime ideals of R, then I is actually contained in one of the graded prime ideals of the family. We give some characterizations of graded compactly packed rings. Further, we examine this property on h – Spec(R. We also define a generalization of graded compactly packed rings, the graded coprimely packed rings. We show that R is a graded compactly packed ring if and only if R is a graded coprimely packed ring whenever R be a graded integral domain and h – dim R = 1.

  18. Computer Security at Nuclear Facilities

    International Nuclear Information System (INIS)

    Cavina, A.

    2013-01-01

    This series of slides presents the IAEA policy concerning the development of recommendations and guidelines for computer security at nuclear facilities. A document of the Nuclear Security Series dedicated to this issue is on the final stage prior to publication. This document is the the first existing IAEA document specifically addressing computer security. This document was necessary for 3 mains reasons: first not all national infrastructures have recognized and standardized computer security, secondly existing international guidance is not industry specific and fails to capture some of the key issues, and thirdly the presence of more or less connected digital systems is increasing in the design of nuclear power plants. The security of computer system must be based on a graded approach: the assignment of computer system to different levels and zones should be based on their relevance to safety and security and the risk assessment process should be allowed to feed back into and influence the graded approach

  19. From Russian weapons grade plutonium to MOX fuel

    International Nuclear Information System (INIS)

    Braehler, G.; Kudriavtsev, E.G.; Seyve, C.

    1997-01-01

    The April 1996, G7 Moscow Summit on nuclear matters provided a political framework for one of the most current significant challenges: ensuring a consistent answer to the weapons grade fissile material disposition issue resulting from the disarmament effort engaged by both the USA and Russia. International technical assessments have showed that the transformation of Weapons grade Plutonium in MOX fuel is a very efficient, safe, non proliferant and economically effective solution. In this regard, COGEMA and SIEMENS, have set up a consistent technical program properly addressing incineration of weapons grade plutonium in MOX fuels. The leading point of this program would be the construction of a Weapons grade Plutonium dedicated MOX fabrication plant in Russia. Such a plant would be based on the COGEMA-SIEMENS industrial capabilities and experience. This facility would be operated by MINATOM which is the partner for COGEMA-SIEMENS. MINATOM is in charge of coordination of the activity of the Russian research and construction institutes. The project take in account international standards for non-proliferation, safety and waste management. France and Germany officials reasserted this position during their last bilateral summits held in Fribourg in February and in Dijon in June 1996. MINATOM and the whole Russian nuclear community have already expressed their interest to cooperate with COGEMA-SIEMENS in the MOX field. This follows governmental-level agreements signed in 1992 by French, German and Russian officials. For years, Russia has been dealing with research and development on MOX fabrication and utilization. So, the COGEMA-SIEMENS MOX proposal gives a realistic answer to the management of weapons grade plutonium with regard to the technical, industrial, cost and schedule factors. (author)

  20. Graded approach for establishment of QA requirements for Type B packaging of radioactive material

    International Nuclear Information System (INIS)

    Fabian, R.R.; Woodruff, K.C.

    1988-01-01

    A study that was conducted by the Nuclear Regulatory Commission for the U.S. Congress to assess the effectiveness of quality assurance (QA) activities has demonstrated a need to modify and improve the application of QA requirements for the nuclear industry. As a result, the packaging community, along with the nuclear industry as a whole, has taken action to increase the efficacy of the QA function. The results of the study indicate that a graded approach for establishing QA requirements is the preferred method. The essence of the graded approach is the establishment of applicable QA requirements to an extent consistent with the importance to safety of an item, component, system, or activity. This paper describes the process that is used to develop the graded approach for QA requirements pertaining to Type B packaging

  1. Experimental and numerical investigation of water flow through spacer grids of nuclear fuel elements using the Open FOAM code; Investigação numérica e experimental do escoamento de água através de grades espaçadoras de elementos combustíveis nucleares utilizando o código OpenFOAM

    Energy Technology Data Exchange (ETDEWEB)

    Vidal, Guilherme A.M.; Vieira, Tiago A.S.; Castro, Higor F.P., E-mail: gvidal.ufmg@gmail.com, E-mail: tiago.vieira.eng@gmail.com, E-mail: higorfabiano@hotmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Mecânica; Santos, André A.C. dos; Silva, Vitor V. A.; Barros Filho, José A., E-mail: aacs@cdtn.br, E-mail: vitors@cdtn.br, E-mail: jabf@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    With the advancement and development of computational tools, the studies of thermofluidodynamic behavior in nuclear fuel elements have been developed in recent years. Of the devices present in these elements, the spacing grids received more attention. They have kept the fuel rods equally spaced and have fins that aim to improve the heat transfer process between the water and the fuel element. Therefore, the grids present an important structural and thermal function. This work was carried out with the purpose of verifying and validating simulations of spacer grids using OpenFOAM (2017) software of Computational Fluid Dynamics (CFD). The simulations were validated using results obtained through the commercial CFD program, Ansys CFX, and experiments available in the literature and obtained in test sections assembled on the Water-Air Circuit (CCA) of the CDTN thermo-hydraulic laboratory.

  2. Nuclear power

    International Nuclear Information System (INIS)

    Abd Khalik Wood

    2005-01-01

    This chapter discussed the following topics related to the nuclear power: nuclear reactions, nuclear reactors and its components - reactor fuel, fuel assembly, moderator, control system, coolants. The topics titled nuclear fuel cycle following subtopics are covered: , mining and milling, tailings, enrichment, fuel fabrication, reactor operations, radioactive waste and fuel reprocessing. Special topic on types of nuclear reactor highlighted the reactors for research, training, production, material testing and quite detail on reactors for electricity generation. Other related topics are also discussed: sustainability of nuclear power, renewable nuclear fuel, human capital, environmental friendly, emission free, impacts on global warming and air pollution, conservation and preservation, and future prospect of nuclear power

  3. 7 CFR 810.404 - Grades and grade requirements for corn.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Grades and grade requirements for corn. 810.404... OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Corn Principles Governing the Application of Standards § 810.404 Grades and grade requirements for corn. Grade Minimum test weight per...

  4. 7 CFR 810.1804 - Grades and grade requirements for sunflower seed.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Grades and grade requirements for sunflower seed. 810... AGRICULTURE OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Sunflower Seed Principles Governing the Application of Standards § 810.1804 Grades and grade requirements for sunflower seed. Grade...

  5. Attendance Policies and Student Grades

    Science.gov (United States)

    Risen, D. Michael

    2007-01-01

    The details described in this case study examine the issues related to attendance policies and how such policies might be legally used to affect student grades. Concepts discussed should cause graduate students in educational administration to reflect on the issues presented from various points of view when the students complete an analysis of the…

  6. Grading Rubrics: Hoopla or Help?

    Science.gov (United States)

    Howell, Rebecca J.

    2014-01-01

    The purpose of the study was to offer some quantitative, multivariate evidence concerning the impact of grading rubric use on academic outcome among American higher education students. Using a pre-post, quasi-experimental research design, cross-sectional data were derived from undergraduates enrolled in an elective during spring and fall 2009 at…

  7. Transportation: Grade 8. Cluster IV.

    Science.gov (United States)

    Calhoun, Olivia H.

    A curriculum guide for grade 8, the document is devoted to the occupational cluster "Transportation." It is divided into five units: surface transportation, interstate transportation, air transportation, water transportation, and subterranean transportation (the Metro). Each unit is introduced by a statement of the topic, the unit's…

  8. Safeguards on nuclear waste

    International Nuclear Information System (INIS)

    Crawford, D.W.

    1995-01-01

    Safeguards and security policies within the Department of Energy (DOE) have been implemented in a graded fashion for the protection, control and accountability of nuclear materials. This graded philosophy has meant that safeguards on low-equity nuclear materials, typically considered of low diversion attractiveness such as waste, has been relegated to minimal controls. This philosophy has been and remains today an acceptable approach for the planning and implementation of safeguards on this material. Nuclear waste protection policy and guidance have been issued due to a lack of clear policy and guidance on the identification and implementation of safeguards controls on waste. However, there are issues related to safe-guarding waste that need to be clarified. These issues primarily stem from increased budgetary and resource pressures to remove materials from safeguards. Finally, there may be an unclear understanding, as to the scope and content of vulnerability assessments required prior to terminating safeguards on waste and other discardable materials and where the authority should lie within the Department for making decisions regarding safeguards termination. This paper examines these issues and the technical basis for Departmental policy for terminating safeguards on waste

  9. Smartphone-based grading of apple quality

    Science.gov (United States)

    Li, Xianglin; Li, Ting

    2018-02-01

    Apple quality grading is a critical issue in apple industry which is one economical pillar of many countries. Artificial grading is inefficient and of poor accuracy. Here we proposed to develop a portable, convenient, real-time, and low cost method aimed at grading apple. Color images of the apples were collected with a smartphone and the grade of sampled apple was assessed by a customized smartphone app, which offered the functions translating RGB color values of the apple to color grade and translating the edge of apple image to weight grade. The algorithms are based on modeling with a large number of apple image at different grades. The apple grade data evaluated by the smartphone are in accordance with the actual data. This study demonstrated the potential of smart phone in apple quality grading/online monitoring at gathering and transportation stage for apple industry.

  10. Procurement Engineering Process for Commercial Grade Item Dedication

    International Nuclear Information System (INIS)

    Park, Jong-Hyuck; Park, Jong-Eun; Kwak, Tack-Hun; Yoo, Keun-Bae; Lee, Sang-Guk; Hong, Sung-Yull

    2006-01-01

    Procurement Engineering Process for commercial grade item dedication plays an increasingly important role in operation management of Korea Nuclear Power Plants. The purpose of the Procurement Engineering Process is the provision and assurance of a high quality and quantity of spare, replacement, retrofit and new parts and equipment while maximizing plant availability, minimizing downtime due to parts unavailability and providing reasonable overall program and inventory cost. In this paper, we will review the overview requirements, responsibilities and the process for demonstrating with reasonable assurance that a procured item for potential nuclear safety related services or other essential plant service is adequate with reasonable assurance for its application. This paper does not cover the details of technical evaluation, selecting critical characteristics, selecting acceptance methods, performing failure modes and effects analysis, performing source surveillance, performing quality surveys, performing special tests and inspections, and the other aspects of effective Procurement Engineering and Commercial Grade Item Dedication. The main contribution of this paper is to provide the provision of an overview of Procurement Engineering Process for commercial grade item

  11. Science communication from women in nuclear fuel development

    International Nuclear Information System (INIS)

    Roy, S.B.

    2013-01-01

    In India, nuclear fuel is required for operating both nuclear research reactors and power reactors. Indian women are extensively involved in nuclear fuel research and production activities. However, the nature and extent of their involvement differs based only on the job required and not on any gender basis. Excluding a few specific safety and security issues, therefore, science and technology communication really does not change according to the gender of the scientist or technologist. Presently in India, nuclear grade uranium metal is required for fuelling research reactors and nuclear grade uranium oxide is being utilized as fuel for power reactors. Hydrometallurgical operations using specific solvents are being used for achieving 'nuclear grade' in both sectors. For production of uranium oxide, purified uranium compounds need to get calcined and reduced for obtaining uranium dioxide of various qualities

  12. Detecting nuclear warheads

    International Nuclear Information System (INIS)

    Fetter, S.; Frolov, V.A.; Prilutsky, O.F.; Rodionov, S.N.; Sagdeev, R.Z.; Miller, M.

    1992-01-01

    To the best of our knowledge, all nuclear weapons contain at least several kilograms of fissile material - material that can sustain a chain reaction. Such material provides the energy for fission explosives such as those that destroyed Hiroshima and Nagasaki; it is also used in the fission trigger modern thermonuclear weapons. The two fissile materials used in US and Soviet warheads are weapon grade uranium (WgU) and weapon-grade plutonium (WgPu). Fissile materials are radioactive; they are very dense and absorb certain radiations very well; and they can be fissioned. This paper reports on the two basic ways to detect fissile material: passive detection of the radiation emitted by its radioactive decay, or active detection involving either radiographing (x-raying) an object with neutrons or high-energy photons and detecting particles emitted by the resulting induced fissions. Passive detection is the preferred technique for verification purposes because of its simplicity and safety

  13. Nuclear technology and mineral recovery

    International Nuclear Information System (INIS)

    Stewart, Richard M.; Niermeyer, Karl E.

    1970-01-01

    The particular aspect of nuclear technology most applicable to the mineral field, as has been pointed out by various authors, is nuclear blasting. The prime target for this nuclear blasting has usually been a large disseminated deposit of copper mineralization which, because of large dimensions, employs the nuclear devices most effectively. From the work of the AEC we know that the larger nuclear devices fragment rock for a lower energy cost per unit of ground broken than do smaller nuclear devices or chemical explosives. A mineralized deposit near the surface is usually not amenable to nuclear fragmentation, nor are the more deeply buried thin deposits. Also, one would not anticipate fragmenting a zone of excessively erratic mineralization with nuclear devices. Many of our mineralized areas would be eliminated using the above criteria, so at this point you are well aware that my self-imposed limitation is to nuclear blasting and large disseminated copper deposits. As with most other industries, copper mining faces rising costs and greater demands for its products. One of the rising cost features peculiar to extractive industries is the reliance placed on production from lower grade deposits as the higher grade deposits are depleted. As the grade or metal content of an orebody decreases more material must be handled to produce a given amount of metal. The increased volume of ore which must be handled as the grade declines requires expansion of facilities and higher capital expenditures. Expansion of facilities for mining, milling, and concentrating of the ore increases the per unit capital cost of the end product--copper. Increased copper consumption will aggravate this situation with demand for more metal, much of which will have to be obtained from lower grade deposits. As the higher grade deposits are depleted, future production will come from those deposits which cannot be exploited economically today. Most familiar of the proposed new methods for copper mining

  14. Nuclear technology and mineral recovery

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Richard M; Niermeyer, Karl E [Anaconda Company, Salt Lake City, UT (United States)

    1970-05-15

    The particular aspect of nuclear technology most applicable to the mineral field, as has been pointed out by various authors, is nuclear blasting. The prime target for this nuclear blasting has usually been a large disseminated deposit of copper mineralization which, because of large dimensions, employs the nuclear devices most effectively. From the work of the AEC we know that the larger nuclear devices fragment rock for a lower energy cost per unit of ground broken than do smaller nuclear devices or chemical explosives. A mineralized deposit near the surface is usually not amenable to nuclear fragmentation, nor are the more deeply buried thin deposits. Also, one would not anticipate fragmenting a zone of excessively erratic mineralization with nuclear devices. Many of our mineralized areas would be eliminated using the above criteria, so at this point you are well aware that my self-imposed limitation is to nuclear blasting and large disseminated copper deposits. As with most other industries, copper mining faces rising costs and greater demands for its products. One of the rising cost features peculiar to extractive industries is the reliance placed on production from lower grade deposits as the higher grade deposits are depleted. As the grade or metal content of an orebody decreases more material must be handled to produce a given amount of metal. The increased volume of ore which must be handled as the grade declines requires expansion of facilities and higher capital expenditures. Expansion of facilities for mining, milling, and concentrating of the ore increases the per unit capital cost of the end product--copper. Increased copper consumption will aggravate this situation with demand for more metal, much of which will have to be obtained from lower grade deposits. As the higher grade deposits are depleted, future production will come from those deposits which cannot be exploited economically today. Most familiar of the proposed new methods for copper mining

  15. Multiphoton imaging of low grade, high grade intraepithelial neoplasia and intramucosal invasive cancer of esophagus

    Science.gov (United States)

    Xu, Jian; Jiang, Liwei; Kang, Deyong; Wu, Xuejing; Xu, Meifang; Zhuo, Shuangmu; Zhu, Xiaoqin; Lin, Jiangbo; Chen, Jianxin

    2017-04-01

    Esophageal squamous cell carcinoma (ESCC) is devastating because of its aggressive lymphatic spread and clinical course. It is believed to occur through low-grade intraepithelial neoplasia (LGIN), high-grade intraepithelial neoplasia (HGIN), and intramucosal invasive cancer (IMC) before transforming to submucosal cancer. In particular, these early lesions (LGIN, HGIN and IMC), which involve no lymph node nor distant metastasis, can be cured by endoscopic treatment. Therefore, early identification of these lesions is important so as to offer a curative endoscopic resection, thus slowing down the development of ESCC. In this work, spectral information and morphological features of the normal esophageal mucosa are first studied. Then, the morphological changes of LGIN, HGIN and IMC are described. Lastly, quantitative parameters are also extracted by calculating the nuclear-to-cytoplasmic ratio of epithelial cells and the pixel density of collagen in the lamina propria. These results show that multiphoton microscopy (MPM) has the ability to identify normal esophageal mucosa, LGIN, HGIN and IMC. With the development of multiphoton endoscope systems for in vivo imaging, combined with a laser ablation system, MPM has the potential to provide immediate pathologic diagnosis and curative treatment of ESCC before the transformation to submucosal cancer in the future.

  16. Nuclear science

    International Nuclear Information System (INIS)

    1989-01-01

    This fact sheet answers specific questions about the Department of Energy's possible acquisition and conversion of a partially completed commercial nuclear power plant to a nuclear materials production facility. The nuclear power plant is the Washington Nuclear Plant number sign 1 owned by the Washington Public Power Supply System and is located on DOE's Hanford Reservation near Richland, Washington

  17. Nuclear science

    International Nuclear Information System (INIS)

    1989-04-01

    This report answers questions about the Department of Energy's possible acquisition and conversion of a partially completed commercial nuclear power plant to a nuclear materials production facility. The nuclear power plant is the Washington Nuclear Plant No.1 owned by the Washington Public Power Supply System and is located on DOE's Hanford Reservation near Richland, Washington

  18. Nuclear medicine

    International Nuclear Information System (INIS)

    Lentle, B.C.

    1986-01-01

    Several growth areas for nuclear medicine were defined. Among them were: cardiac nuclear medicine, neuro-psychiatric nuclear medicine, and cancer diagnosis through direct tumor imaging. A powerful new tool, Positron Emission Tomography (PET) was lauded as the impetus for new developments in nuclear medicine. The political environment (funding, degree of autonomy) was discussed, as were the economic and scientific environments

  19. Nuclear option

    Energy Technology Data Exchange (ETDEWEB)

    Kemm, K R

    1978-05-01

    The global outlook is that nuclear reactors are here to stay and South Africa has already entered the nuclear power stakes. This article discusses the rocketing oil prices, and the alternatives that can be used in power generation, the good safety record of the nuclear industry and the effect that South Africa's first nuclear power station should have on the environment.

  20. Nuclear resisters

    International Nuclear Information System (INIS)

    1981-01-01

    The booklet contains six papers by different authors, under the headings: dangers along the nuclear fuel cycle; the nuclear profiteers; the nuclear state is a police state; a non-disposable future (renewable energy sources, energy conservation); nuclear weapons - out of control; man made madness. (U.K.)

  1. A study on the establishment of safety assessment guidelines of commercial grade item dedication in digitalized safety systems

    International Nuclear Information System (INIS)

    Hwang, H. S.; Kim, B. R.; Oh, S. H.

    1999-01-01

    Because of obsolescing the components used in safety related systems of nuclear power plants, decreasing the number of suppliers qualified for the nuclear QA program and increasing maintenance costs of them, utilities have been considering to use commercial grade digital computers as an alternative for resolving such issues. However, commercial digital computers use the embedded pre-existing software, including operating system software, which are not developed by using nuclear grade QA program. Thus, it is necessary for utilities to establish processes for dedicating digital commercial grade items. A regulatory body also needs guidance to evaluate the digital commercial products properly. This paper surveyed the regulations and their regulatory guides, which establish the requirements for commercial grade items dedication, industry standards and guidances applicable to safety related systems. This paper provides some guidelines to be applied in evaluating the safety of digital upgrades and new digital plant protection systems in Korea

  2. Nuclear links

    International Nuclear Information System (INIS)

    1981-01-01

    The subject is dealt with in sections: introduction; energy and the third world; world energy consumption 1978; oil -the energy dilemma; nuclear chains - introduction; uranium; Namibia; enrichment and reprocessing; countries with enrichment and reprocessing facilities; waste; conclusion; why take the nuclear option; third world countries with nuclear reactors; the arms connection; government spending and human resources 1977 (by countries); nuclear power - the final solution; the fascists; world bank; campaigns; community action in Plogoff; Australian labour movement; NUM against nuclear power; Scottish campaign; students against nuclear energy; anti-nuclear campaign; partizans; 3W1 disarmament and development; campaign ATOM; CANUC; 3W1; SANE. (U.K.)

  3. Approaches for Securing the Nuclear Fuel Cycle

    International Nuclear Information System (INIS)

    Kim, Jae San; Kim, Min Su; Jo, Seong Youn

    2007-01-01

    The greatest challenge to international nuclear nonproliferation regime is posed by nuclear energy's dual nature for both peaceful and military purposes. Uranium enrichment and spent nuclear fuel (SNF) reprocessing (sensitive nuclear technologies) are critical from the non-proliferation viewpoint because they may be used to produce weapons-grade nuclear materials. Therefore, since 1970s the world community started to develop further measures to curb the spread of sensitive nuclear technologies. The establishment of a Nuclear Suppliers Group (NSG) in 1975 was one such measure. The NSG united countries which voluntarily agreed to coordinate their legislation regarding export of nuclear materials, equipment and technologies to countries not possessing nuclear weapons. Alongside measures to limit the spread of sensitive nuclear technologies, multilateral approaches to the nuclear fuel cycle (NFC) started to be discussed. It's becoming increasingly important to link the objective need for an expanded use of nuclear energy with strengthening nuclear non-proliferation by preventing the spread of sensitive nuclear technologies and securing access for interested countries to NFC products and services

  4. Gradings on simple Lie algebras

    CERN Document Server

    Elduque, Alberto

    2013-01-01

    Gradings are ubiquitous in the theory of Lie algebras, from the root space decomposition of a complex semisimple Lie algebra relative to a Cartan subalgebra to the beautiful Dempwolff decomposition of E_8 as a direct sum of thirty-one Cartan subalgebras. This monograph is a self-contained exposition of the classification of gradings by arbitrary groups on classical simple Lie algebras over algebraically closed fields of characteristic not equal to 2 as well as on some nonclassical simple Lie algebras in positive characteristic. Other important algebras also enter the stage: matrix algebras, the octonions, and the Albert algebra. Most of the presented results are recent and have not yet appeared in book form. This work can be used as a textbook for graduate students or as a reference for researchers in Lie theory and neighboring areas.

  5. Nuclear weapons complex

    International Nuclear Information System (INIS)

    Rezendes, V.S.

    1992-04-01

    In addition to long-standing safety and environmental problems plaguing the nuclear weapons complex, this paper reports that the Department of Energy (DOE) faces a major new challenge-how to reconfigure the weapons complex to meet the nation's defense needs in the 21st century. Key decisions still need to be made about the size of the complex; where, if necessary, to relocate various operations; what technologies to use for new tritium production; and what to do with excess weapons-grade material. The choices confronting DOE and Congress are difficult given the conflicting demands for limited resources

  6. Desalination and nuclear energy

    International Nuclear Information System (INIS)

    Romeijn, A.A.

    1992-01-01

    The techniques for fresh water production from seawater have matured and capacities have increased considerably over the past decades. It is feasible to combine seawater desalination with the generation of electricity since power stations can provide energy and low grade heat during off peak periods for the purpose of fresh water production. A dual purpose installation, combining a seawater desalination facility with a light water reactor power generation station promises interesting possibilities. The case in South Africa, where nuclear power stations are most economically sited far from the inland coal fields, is discussed. 1 ill

  7. Code Analyses Supporting PIE of Weapons-Grade MOX Fuel

    International Nuclear Information System (INIS)

    Ott, Larry J.; Bevard, Bruce Balkcom; Spellman, Donald J.; McCoy, Kevin

    2010-01-01

    The U.S. Department of energy has decided to dispose of a portion of the nation's surplus weapons-grade plutonium by reconstituting it into mixed oxide (MOX) fuel and irradiating the fuel in commercial power reactors. Four lead test assemblies (LTAs) were manufactured with weapons-grade mixed oxide (WG-MOX) fuel and irradiated in the Catawba Nuclear Station Unit 1, to a maximum fuel rod burnup of ∼47.3 GWd/MTHM. As part of the fuel qualification process, five rods with varying burnups and initial plutonium contents were selected from one assembly and shipped to the Oak Ridge National Laboratory (ORNL) for hot cell examination. ORNL has provided analytical support for the post-irradiation examination (PIE) of these rods via extensive fuel performance modeling which has aided in instrument settings and PIE data interpretation. The results of these fuel performance simulations are compared in this paper with available PIE data.

  8. Grade Expectations: Rationality and Overconfidence

    Science.gov (United States)

    Magnus, Jan R.; Peresetsky, Anatoly A.

    2018-01-01

    Confidence and overconfidence are essential aspects of human nature, but measuring (over)confidence is not easy. Our approach is to consider students' forecasts of their exam grades. Part of a student's grade expectation is based on the student's previous academic achievements; what remains can be interpreted as (over)confidence. Our results are based on a sample of about 500 second-year undergraduate students enrolled in a statistics course in Moscow. The course contains three exams and each student produces a forecast for each of the three exams. Our models allow us to estimate overconfidence quantitatively. Using these models we find that students' expectations are not rational and that most students are overconfident, in agreement with the general literature. Less obvious is that overconfidence helps: given the same academic achievement students with larger confidence obtain higher exam grades. Female students are less overconfident than male students, their forecasts are more rational, and they are also faster learners in the sense that they adjust their expectations more rapidly. PMID:29375449

  9. Grade Expectations: Rationality and Overconfidence

    Directory of Open Access Journals (Sweden)

    Jan R. Magnus

    2018-01-01

    Full Text Available Confidence and overconfidence are essential aspects of human nature, but measuring (overconfidence is not easy. Our approach is to consider students' forecasts of their exam grades. Part of a student's grade expectation is based on the student's previous academic achievements; what remains can be interpreted as (overconfidence. Our results are based on a sample of about 500 second-year undergraduate students enrolled in a statistics course in Moscow. The course contains three exams and each student produces a forecast for each of the three exams. Our models allow us to estimate overconfidence quantitatively. Using these models we find that students' expectations are not rational and that most students are overconfident, in agreement with the general literature. Less obvious is that overconfidence helps: given the same academic achievement students with larger confidence obtain higher exam grades. Female students are less overconfident than male students, their forecasts are more rational, and they are also faster learners in the sense that they adjust their expectations more rapidly.

  10. Measure of uncertainty in regional grade variability

    NARCIS (Netherlands)

    Tutmez, B.; Kaymak, U.; Melin, P.; Castillo, O.; Gomez Ramirez, E.; Kacprzyk, J.; Pedrycz, W.

    2007-01-01

    Because the geological events are neither homogeneous nor isotropic, the geological investigations are characterized by particularly high uncertainties. This paper presents a hybrid methodology for measuring of uncertainty in regional grade variability. In order to evaluate the fuzziness in grade

  11. Constitutive modeling and finite element procedure development for stress analysis of prismatic high temperature gas cooled reactor graphite core components

    International Nuclear Information System (INIS)

    Mohanty, Subhasish; Majumdar, Saurindranath; Srinivasan, Makuteswara

    2013-01-01

    Highlights: • Finite element procedure developed for stress analysis of HTGR graphite component. • Realistic fluence profile and reflector brick shape considered for the simulation. • Also realistic H-451 grade material properties considered for simulation. • Typical outer reflector of a GT-MHR type reactor considered for numerical study. • Based on the simulation results replacement of graphite bricks can be scheduled. -- Abstract: High temperature gas cooled reactors, such as prismatic and pebble bed reactors, are increasingly becoming popular because of their inherent safety, high temperature process heat output, and high efficiency in nuclear power generation. In prismatic reactors, hexagonal graphite bricks are used as reflectors and fuel bricks. In the reactor environment, graphite bricks experience high temperature and neutron dose. This leads to dimensional changes (swelling and or shrinkage) of these bricks. Irradiation dimensional changes may affect the structural integrity of the individual bricks as well as of the overall core. The present paper presents a generic procedure for stress analysis of prismatic core graphite components using graphite reflector as an example. The procedure is demonstrated through commercially available ABAQUS finite element software using the option of user material subroutine (UMAT). This paper considers General Atomics Gas Turbine-Modular Helium Reactor (GT-MHR) as a bench mark design to perform the time integrated stress analysis of a typical reflector brick considering realistic geometry, flux distribution and realistic irradiation material properties of transversely isotropic H-451 grade graphite

  12. Constitutive modeling and finite element procedure development for stress analysis of prismatic high temperature gas cooled reactor graphite core components

    Energy Technology Data Exchange (ETDEWEB)

    Mohanty, Subhasish, E-mail: smohanty@anl.gov [Argonne National Laboratory, South Cass Avenue, Argonne, IL 60439 (United States); Majumdar, Saurindranath [Argonne National Laboratory, South Cass Avenue, Argonne, IL 60439 (United States); Srinivasan, Makuteswara [U.S. Nuclear Regulatory Commission, Washington, DC 20555 (United States)

    2013-07-15

    Highlights: • Finite element procedure developed for stress analysis of HTGR graphite component. • Realistic fluence profile and reflector brick shape considered for the simulation. • Also realistic H-451 grade material properties considered for simulation. • Typical outer reflector of a GT-MHR type reactor considered for numerical study. • Based on the simulation results replacement of graphite bricks can be scheduled. -- Abstract: High temperature gas cooled reactors, such as prismatic and pebble bed reactors, are increasingly becoming popular because of their inherent safety, high temperature process heat output, and high efficiency in nuclear power generation. In prismatic reactors, hexagonal graphite bricks are used as reflectors and fuel bricks. In the reactor environment, graphite bricks experience high temperature and neutron dose. This leads to dimensional changes (swelling and or shrinkage) of these bricks. Irradiation dimensional changes may affect the structural integrity of the individual bricks as well as of the overall core. The present paper presents a generic procedure for stress analysis of prismatic core graphite components using graphite reflector as an example. The procedure is demonstrated through commercially available ABAQUS finite element software using the option of user material subroutine (UMAT). This paper considers General Atomics Gas Turbine-Modular Helium Reactor (GT-MHR) as a bench mark design to perform the time integrated stress analysis of a typical reflector brick considering realistic geometry, flux distribution and realistic irradiation material properties of transversely isotropic H-451 grade graphite.

  13. Disposal of Surplus Weapons Grade Plutonium

    International Nuclear Information System (INIS)

    Alsaed, H.; Gottlieb, P.

    2000-01-01

    The Office of Fissile Materials Disposition is responsible for disposing of inventories of surplus US weapons-usable plutonium and highly enriched uranium as well as providing, technical support for, and ultimate implementation of, efforts to obtain reciprocal disposition of surplus Russian plutonium. On January 4, 2000, the Department of Energy issued a Record of Decision to dispose of up to 50 metric tons of surplus weapons-grade plutonium using two methods. Up to 17 metric tons of surplus plutonium will be immobilized in a ceramic form, placed in cans and embedded in large canisters containing high-level vitrified waste for ultimate disposal in a geologic repository. Approximately 33 metric tons of surplus plutonium will be used to fabricate MOX fuel (mixed oxide fuel, having less than 5% plutonium-239 as the primary fissile material in a uranium-235 carrier matrix). The MOX fuel will be used to produce electricity in existing domestic commercial nuclear reactors. This paper reports the major waste-package-related, long-term disposal impacts of the two waste forms that would be used to accomplish this mission. Particular emphasis is placed on the possibility of criticality. These results are taken from a summary report published earlier this year

  14. Management of Spent Nuclear Fuel from Nuclear Power Plant Reactor

    International Nuclear Information System (INIS)

    Wati, Nurokhim

    2008-01-01

    Management of spent nuclear fuel from Nuclear Power Plant (NPP) reactor had been studied to anticipate program of NPP operation in Indonesia. In this paper the quantity of generated spent nuclear fuel (SNF) is predicted based on the national electrical demand, power grade and type of reactor. Data was estimated using Pressurized Water Reactor (PWR) NPP type 1.000 MWe and the SNF management overview base on the experiences of some countries that have NPP. There are four strategy nuclear fuel cycle which can be developed i.e: direct disposal, reprocessing, DUPlC (Direct Use of Spent PWR Fuel In Candu) and wait and see. There are four alternative for SNF management i.e : storage at the reactor building (AR), away from reactor (AFR) using wet centralized storage, dry centralized storage AFR and prepare for reprocessing facility. For the Indonesian case, centralized facility of the wet type is recommended for PWR or BWR spent fuel. (author)

  15. Safety Review related to Commercial Grade Digital Equipment in Safety System

    International Nuclear Information System (INIS)

    Yu, Yeongjin; Park, Hyunshin; Yu, Yeongjin; Lee, Jaeheung

    2013-01-01

    The upgrades or replacement of I and C systems on safety system typically involve digital equipment developed in accordance with non-nuclear standards. However, the use of commercial grade digital equipment could include the vulnerability for software common-mode failure, electromagnetic interference and unanticipated problems. Although guidelines and standards for dedication methods of commercial grade digital equipment are provided, there are some difficulties to apply the methods to commercial grade digital equipment for safety system. This paper focuses on regulatory guidelines and relevant documents for commercial grade digital equipment and presents safety review experiences related to commercial grade digital equipment in safety system. This paper focuses on KINS regulatory guides and relevant documents for dedication of commercial grade digital equipment and presents safety review experiences related to commercial grade digital equipment in safety system. Dedication including critical characteristics is required to use the commercial grade digital equipment on safety system in accordance with KEPIC ENB 6370 and EPRI TR-106439. The dedication process should be controlled in a configuration management process. Appropriate methods, criteria and evaluation result should be provided to verify acceptability of the commercial digital equipment used for safety function

  16. The pathologist's mean grade is constant and individualizes the prognostic value of bladder cancer grading.

    Science.gov (United States)

    van Rhijn, Bas W G; van Leenders, Geert J L H; Ooms, Bert C M; Kirkels, Wim J; Zlotta, Alexandre R; Boevé, Egbert R; Jöbsis, Adriaan C; van der Kwast, Theo H

    2010-06-01

    A new grading system for bladder cancer (BCa) was adopted in 2004 to reduce observer variability and provide better prognostic information. We compared the World Health Organization (WHO) 1973 and 2004 systems for observer variability and prognosis. Slides of 173 primary non-muscle-invasive BCa were reviewed two times by four pathologists. Intra- and interobserver variability were assessed using κ statistics. We determined the mean grade (eg, G1/low malignant potential is 1 grade point, G2/low grade is 2 grade points) of the pathologists per grading cycle. Kaplan-Meier analyses were applied for prediction of recurrence and progression. For WHO 2004 and 1973 grading, the agreement between the pathologists was 39-74% (κ: 0.14-0.58) and 39-64% (κ: 0.15-0.41), respectively. The intraobserver agreement varied from 71% to 88% (κ: 0.55-0.81). The mean grade of a pathologist was constant (difference below 0.1 grade point) irrespective of the grading system. Conversely, mean-grade differences among the pathologists were high, up to 0.7 grade point. The mean grades for the WHO 2004 system were 0.3-0.5 grade point higher than those of WHO 1973. Mean grade distinguished low and high graders among the pathologists and was strongly linked with risk of progression in each grade category. The variation in mean grade among individual pathologists exceeded the grade shift caused by WHO 2004 grading. Knowledge of the pathologist's mean grade allows a better assessment of the prognostic value of grading. Mean grade has the potential to become a tool for quality assurance in pathology. Copyright © 2009 European Association of Urology. Published by Elsevier B.V. All rights reserved.

  17. Examining Text Complexity in the Early Grades

    Science.gov (United States)

    Fitzgerald, Jill; Elmore, Jeff; Hiebert, Elfrieda H.; Koons, Heather H.; Bowen, Kimberly; Sanford-Moore, Eleanor E.; Stenner, A. Jackson

    2016-01-01

    The Common Core raises the stature of texts to new heights, creating a hubbub. The fuss is especially messy at the early grades, where children are expected to read more complex texts than in the past. But early-grades teachers have been given little actionable guidance about text complexity. The authors recently examined early-grades texts to…

  18. Registration Patterns Under Two Different Grading Systems.

    Science.gov (United States)

    Remley, Audrey W.

    In the early 1960's, Westminster College adopted a new grading system, with the traditional grade levels of A, B, C, D, and F converted to DN (Distinction), HP (High Pass), P (Pass), and NC (No Credit). NC replaced both D and F of the old system, and grade point averages were abolished, in an effort to encourage students to register in more…

  19. Forecasting and recruitment in graded manpower systems

    NARCIS (Netherlands)

    van Nunen, J.A.E.E.; Wessels, J.

    1977-01-01

    In this paper a generalized Markov model is introduced to describe the dynamic behaviour of an individual employee in a graded Manpower system. Characteristics like the employee's grade, his educational level, his age and the time spent in his actual grade, can be incorporated in the Markov model.

  20. Demystify Learning Expectations to Address Grade Inflation

    Science.gov (United States)

    Hodges, Linda C.

    2014-01-01

    This article describes the subject of "grade inflation," a reference to educators giving higher grades to student work than their expectations for student achievement warrant. Of the many reasons why this practice happens, Hodges specifically discusses inflating grades as "a natural consequence" when the faculty really…

  1. Grade Inflation: An Issue for Higher Education?

    Science.gov (United States)

    Caruth, Donald L.; Caruth, Gail D.

    2013-01-01

    Grade inflation impacts university credibility, student courses of study, choices of institution, and other areas. There has been an upward shift in grades without a corresponding upward shift in knowledge gained. Some of the most frequently mentioned causes of grade inflation are: (1) student evaluations of professors; (2) student teacher…

  2. Does Education Corrupt? Theories of Grade Inflation

    Science.gov (United States)

    Oleinik, Anton

    2009-01-01

    Several theories of grade inflation are discussed in this review article. It is argued that grade inflation results from the substitution of criteria specific to the search for truth by criteria of quality control generated outside of academia. Particular mechanisms of the grade inflation that occurs when a university is transformed into a…

  3. Sustainability of Water Cooled Reactors - Energy Balance for Low Grade Uranium Resources

    International Nuclear Information System (INIS)

    Strupczewski, A.

    2011-01-01

    The opponents of nuclear power claim that as uranium resources get exhausted the energy needed to mine low grade uranium ore will be larger than the energy that can be obtained from fission in a nuclear power plant. This would result in loss of sustainability of nuclear power, with the negative energy balance expected within the next 40-60 years. Since the opponents state clearly that the ore containing less than 0.013% U 3 O 8 cannot yield positive energy balance, the study of the Institute of Atomic Energy in Poland referenced three mines of decreasing ore grade: Ranger 0.234% U 3 O 8 , Rossing 0.028% U 3 O 8 and Trekkopje 0.00126% U 3 O 8 , that is with ore grade below the postulated cut off value. The study considered total energy needs for uranium mining, including not only electricity needed for mining and milling, for water treatment and delivery, but also fuel for transportation and ore crushing, explosives for rock blasting, chemicals for uranium leaching and the energy needed for mine reclamation after completed exploitation. It has been shown that the energy estimates of nuclear opponents are wrong for Ranger mine and go off much further for the mines with lower uranium ore grades. The reasons for erroneous reasoning of nuclear opponents have been found. Their errors arise from treating the uranium ore deposits as if their layout and properties were the same as those of uranium ore mined in the US in the 70-ies. This results in an oversimplified formula, which yields large errors when the thickness of the overlayer is less than it was in the US. In addition the energy needs claimed for mine reclamation are much too high. The study showed that the energy needed for very low grade uranium ore mining and milling increases but the overall energy balance of the nuclear fuel cycle remains strongly positive. (author)

  4. Zirconium sponge and other forms of virgin metal for nuclear applications - approved standard 1973

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    This specification covers virgin zirconium metal commonly designated as sponge because of its porous, sponge-like texture, but it may also take other forms such as chunklets. One grade is described which is designated as reactor grade R-1, suitable for use in nuclear applications. The most important characteristic of the reactor grade is its low nuclear cross section as achieved by removal of hafnium and careful quality control in manufacturing procedures to prevent contamination with other high cross section materials

  5. Nuclear Power

    International Nuclear Information System (INIS)

    Douglas-Hamilton, J.; Home Robertson, J.; Beith, A.J.

    1987-01-01

    In this debate the Government's policy on nuclear power is discussed. Government policy is that nuclear power is the safest and cleanest way of generating electricity and is cheap. Other political parties who do not endorse a nuclear energy policy are considered not to be acting in the people's best interests. The debate ranged over the risks from nuclear power, the UK safety record, safety regulations, and the environmental effects of nuclear power. The Torness nuclear power plant was mentioned specifically. The energy policy of the opposition parties is strongly criticised. The debate lasted just over an hour and is reported verbatim. (UK)

  6. International agreements on nuclear weapons

    International Nuclear Information System (INIS)

    Dombey, N.

    1982-01-01

    The satellite detection of a nuclear explosion in the South Atlantic and Israel's destruction of a research reactor in Iraq make it essential to strengthen existing monitoring and enforcement programs to prevent proliferation. While there was no reliable evidence that either South Africa or Iraq was violating non-proliferation agreements, worst case scenarios can demonstrate to unfriendly countries that South Africa had diverted fuel to test a nuclear weapon and that Iraq is intending to produce weapons-grade plutonium 239. The situation can be improved by formulating better terms and conditions for internationalizing access to materials. Nuclear suppliers need to agree on terms that will assure their customers that contracts for civil programs will be honored. The International Atomic Energy Agency (IAEA), which includes both nuclear suppliers and customers, could achieve stronger agreements that take into account recent technological advances that will expand enrichment and reprocessing activities. 23 references, 1 figure

  7. The Relationship of Grade Span in 9th Grade to Math Achievement in High School

    Science.gov (United States)

    West, John; Miller, Mary Lou; Myers, Jim; Norton, Timothy

    2015-01-01

    Purpose, Scope, and Method of Study: The purpose of this study was to determine if a correlation exists between grade span for ninth grade and gains in math achievement test scores in 10th grade and 12th grade. A quantitative, longitudinal, correlational research design was employed to investigate the research questions. The population was high…

  8. High grade glioma: Imaging combined with pathological grade defines management and predicts prognosis

    International Nuclear Information System (INIS)

    Burnet, Neil G.; Lynch, Andrew G.; Jefferies, Sarah J.; Price, Stephen J.; Jones, Phil H.; Antoun, Nagui M.; Xuereb, John H.; Pohl, Ute

    2007-01-01

    Introduction: There is ambiguity in pathological grading of high grade gliomas within the WHO 2000 classification, especially those with predominant oligodendroglial differentiation. Patients and methods: All adult high grade gliomas treated radically, 1996-2005, were assessed. Cases in which pathology was grade III but radiology suggested glioblastoma (GBM) were classified as 'grade III/IV'; their pathology was reviewed. Results: Data from 245 patients (52 grade III, 18 grade III/IV, 175 GBM) were analysed using a Cox Proportional Hazards model. On pathology review, features suggestive of more aggressive behaviour were found in all 18 grade III/IV tumours. Oligodendroglial components with both necrosis and microvascular proliferation were present in 7. MIB-1 counts for the last 8 were all above 14%, mean 27%. Median survivals were: grade III 34 months, grade III/IV 10 months, GBM 11 months. Survival was not significantly different between grade III/IV and GBM. Patients with grade III/IV tumours had significantly worse outcome than grade III, with a hazard of death 3.7 times higher. Conclusions: The results highlight the current inconsistency in pathological grading of high grade tumours, especially those with oligodendroglial elements. Patients with histological grade III tumours but radiological appearances suggestive of GBM should be managed as glioblastoma

  9. Association of Grade Configuration with School Climate for 7th and 8th Grade Students

    Science.gov (United States)

    Malone, Marisa; Cornell, Dewey; Shukla, Kathan

    2017-01-01

    Educational authorities have questioned whether middle schools provide the best school climate for 7th and 8th grade students, and proposed that other grade configurations such as K-8th grade schools may provide a better learning environment. The purpose of this study was to compare 7th and 8th grade students' perceptions of 4 key features of…

  10. Comparing Dropout Predictors for Two State-Level Panels Using Grade 6 and Grade 8 Data

    Science.gov (United States)

    Franklin, Bobby J.; Trouard, Stephen B.

    2016-01-01

    The purpose of this study was to examine the effectiveness of dropout predictors across time. Two state-level high school graduation panels were selected to begin with the seventh and ninth grades but end at the same time. The first panel (seventh grade) contained 29,554 students and used sixth grade predictors. The second panel (ninth grade)…

  11. Grade Inflation Marches On: Grade Increases from the 1990s to 2000s

    Science.gov (United States)

    Kostal, Jack W.; Kuncel, Nathan R.; Sackett, Paul R.

    2016-01-01

    Grade inflation threatens the integrity of college grades as indicators of academic achievement. In this study, we contribute to the literature on grade inflation by providing the first estimate of the size of grade increases at the student level between the mid-1990s and mid-2000s. By controlling for student characteristics and course-taking…

  12. The effect of various grading scales on student grade point averages.

    Science.gov (United States)

    Barnes, Kelli D; Buring, Shauna M

    2012-04-10

    To investigate changes in and the impact of grading scales from 2005 to 2010 and explore pharmacy faculty and student perceptions of whole-letter and plus/minus grading scales on cumulative grade point averages (GPAs) in required courses. Grading scales used in 2010 at the University of Cincinnati College of Pharmacy were retrospectively identified and compared to those used in 2005. Mean GPA was calculated using a whole-letter grading scale and a plus/minus grading scale to determine the impact of scales on GPA. Faculty members and students were surveyed regarding their perceptions of plus/minus grading. Nine unique grading scales were used throughout the curriculum, including plus/minus (64%) and whole-letter (21%) grading scales. From 2005 to 2010 there was transition from use of predominantly whole-letter scales to plus/minus grading scales. The type of grading scale used did not affect the mean cumulative GPA. Students preferred use of a plus-only grading scale while faculty members preferred use of a plus/minus grading scale. The transition from whole-letter grading to plus/minus grading in courses from 2005 to 2010 reflects pharmacy faculty members' perception that plus/minus grading allows for better differentiation between students' performances.

  13. JPRS Report, Nuclear Developments

    National Research Council Canada - National Science Library

    1991-01-01

    Partial Contents: Medium Range Missiles, Rocket Engine, Nuclear Submarine, Nuclear Reactor, Nuclear Inspection, Nuclear Weapons, Transfer Technology, Scud, Safety, Nuclear Power, Chernobyl Trial, ,CHemical Weapons...

  14. Nuclear forensics

    International Nuclear Information System (INIS)

    Venugopal, V.

    2010-01-01

    Nuclear forensics is the analysis of nuclear materials recovered from either the capture of unused materials, or from the radioactive debris following a nuclear explosion and can contribute significantly to the identification of the sources of the materials and the industrial processes used to obtain them. In the case of an explosion, nuclear forensics can also reconstruct key features of the nuclear device. Nuclear forensic analysis works best in conjunction with other law enforcement, radiological protection dosimetry, traditional forensics, and intelligence work to provide the basis for attributing the materials and/or nuclear device to its originators. Nuclear forensics is a piece of the overall attribution process, not a stand-alone activity

  15. Nuclear power

    International Nuclear Information System (INIS)

    1987-01-01

    ''Nuclear Power'' describes how a reactor works and examines the different designs including Magnox, AGR, RBMK and PWR. It charts the growth of nuclear generation in the world and its contributions to world energy resources. (author)

  16. Nuclear Scans

    Science.gov (United States)

    Nuclear scans use radioactive substances to see structures and functions inside your body. They use a special ... images. Most scans take 20 to 45 minutes. Nuclear scans can help doctors diagnose many conditions, including ...

  17. Findings of the inspection grading system on industrial radiography

    International Nuclear Information System (INIS)

    Gloria Doloressa

    2011-01-01

    The use of industrial radiography techniques evolve rapidly and widely. Various jobs in industry require the examination of welding techniques / connecting pipes and metal construction. The use of industrial radiography is one type of utilization of nuclear energy must get control so that its use does not cause harmful impacts to worker safety, community, and environment. Regulations is done through inspections, in order to supervise the observance of the terms in the licensing and legislation in the field of nuclear safety. The main purpose of inspection is to ensure the utilization of radiation sources of radiation have been used with. Findings of the inspection is a decline in the performance of licensees in meeting safety requirements. The Grading System to the findings of the inspection needs to be done to improve the effectiveness and efficiency of inspection, and it is expected that the company can improve the management of radiation safety. (author)

  18. Nuclear energy

    International Nuclear Information System (INIS)

    Kuhn, W.

    1986-01-01

    This loose-leaf collection is made up of five didactically prepared units covering the following subjects: basic knowledge on nuclear energy, nuclear energy in relation to energy economy, site issues, environmental compatibility of nuclear energy, and nuclear energy in the focus of political and social action. To this was added a comprehensive collection of material: specific scientific background material, a multitude of tables, diagrams, charts etc. for copying, as well as 44 transparent charts, mostly in four colours. (orig./HP) [de

  19. Nuclear structure

    International Nuclear Information System (INIS)

    Eastham, D.A.; Joy, T.

    1986-01-01

    The paper on 'nuclear structure' is the Appendix to the Daresbury (United Kingdom) Annual Report 1985/86, and contains the research work carried out at the Nuclear Structure Facility, Daresbury, within that period. During the year a total of 74 experiments were scheduled covering the main areas of activity including: nuclear collective motion, nuclei far from stability, and nuclear collisions. The Appendix contains brief reports on these experiments and associated theory. (U.K.)

  20. Nuclear terrorism

    International Nuclear Information System (INIS)

    2002-01-01

    Recent reports of alleged terrorist plans to build a 'dirty bomb' have heightened longstanding concerns about nuclear terrorism. This briefing outlines possible forms of attack, such as: detonation of a nuclear weapon; attacks involving radioactive materials; attacks on nuclear facilities. Legislation addressing these risks and the UK's strategy for coping with them are also considered

  1. Nuclear power

    International Nuclear Information System (INIS)

    d'Easum, Lille.

    1976-03-01

    An environmentalist's criticism of nuclear energy is given, on a layman's level. Such subjects as conflict of interest in controlling bodies, low-level radiation, reactor safety, liability insurance, thermal pollution, economics, heavy water production, export of nuclear technology, and the history of the anti-nuclear movement are discussed in a sensationalistic tone. (E.C.B.)

  2. Nuclear alerts

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    Anti-nuclear demonstrations against the deployment of new US missiles were held in Nato Europe. As no agreement has yet been reached at the US-Soviet Intermediate Nuclear Forces talks in Geneva, the deployment of nuclear missiles in Europe has started

  3. Nuclear questions

    International Nuclear Information System (INIS)

    Berg, Eugene

    2012-01-01

    Civilian and military nuclear questions fill a multitude of publications these days, especially after the Japanese tsunami and the Fukushima disaster. The author analyses some of them and highlights the links between civil and military nuclear industries, the realities of the nuclear cycle and related industrial questions before concluding on the controversial issue of weapons and their proliferation potential

  4. Nuclear decommissioning

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    The paper on nuclear decommissioning was presented by Dr H. Lawton to a meeting of the British Nuclear Energy Society and Institution of Nuclear Engineers, 1986. The decommissioning work currently being undertaken on the Windscale advanced gas cooled reactor (WAGR) is briefly described, along with projects in other countries, development work associated with the WAGR operation and costs. (U.K.)

  5. Nuclear electronics

    International Nuclear Information System (INIS)

    Friese, T.

    1981-09-01

    A short survey is given on nuclear radiation detectors and nuclear electronics. It is written for newcomers and those, who are not very familiar with this technique. Some additional information is given on typical failures in nuclear measurement systems. (orig.) [de

  6. Initial Comparison of Baseline Physical and Mechanical Properties for the VHTR Candidate Graphite Grades

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, Mark C. [Idaho National Lab. (INL), Idaho Falls, ID (United States). VHTR Program

    2014-09-01

    High-purity graphite is the core structural material of choice in the Very High Temperature Reactor (VHTR) design, a graphite-moderated, helium-cooled configuration capable of producing thermal energy for power generation as well as process heat for industrial applications that require temperatures higher than the outlet temperatures of present nuclear reactors. The Baseline Graphite Characterization Program is establishing accurate as-manufactured mechanical and physical property distributions in nuclear-grade graphites by providing comprehensive data that captures the level of variation in measured values. In addition to providing a thorough comparison between these values in different graphite grades, the program is also carefully tracking individual specimen source, position, and orientation information in order to provide comparisons both in specific properties and in the associated variability between different lots, different billets, and different positions from within a single billet. This report is a preliminary comparison between each of the grades of graphite that are considered “candidate” grades from four major international graphite producers. These particular grades (NBG-18, NBG-17, PCEA, IG-110, and 2114) are the major focus of the evaluations presently underway on irradiated graphite properties through the series of Advanced Graphite Creep (AGC) experiments. NBG-18, a medium-grain pitch coke graphite from SGL from which billets are formed via vibration molding, was the favored structural material in the pebble-bed configuration. NBG-17 graphite from SGL is essentially NBG-18 with the grain size reduced by a factor of two. PCEA, petroleum coke graphite from GrafTech with a similar grain size to NBG-17, is formed via an extrusion process and was initially considered the favored grade for the prismatic layout. IG-110 and 2114, from Toyo Tanso and Mersen (formerly Carbone Lorraine), respectively, are fine-grain grades produced via an isomolding

  7. Independent V and V for Safety Grade I and C System

    International Nuclear Information System (INIS)

    Lee, Jang Soo; Kwon, Kee Choon; Lee, Dong Young

    2010-08-01

    Through KNICS and Nu-Tech 2012, a MMIS(Man-Machine Interface System) package for nuclear plants was localized and is expected to be applied to SUN 1,2 plants. This study is aimed to support the application of the MMIS package including the following technologies that meet strengthened regulation requirements and enhanced utility's performance requirements to nuclear plants. - Dedication to real time operating system for safety-grade computers - V and V of the broadband communication network for safety information - Independent V and V for application of programmable logic controllers to nuclear plants - Development strategy for an integrated SW development tool for control devices

  8. Independent V and V for Safety Grade I and C System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jang Soo; Kwon, Kee Choon; Lee, Dong Young [KAERI, Daejeon (Korea, Republic of)

    2010-08-15

    Through KNICS and Nu-Tech 2012, a MMIS(Man-Machine Interface System) package for nuclear plants was localized and is expected to be applied to SUN 1,2 plants. This study is aimed to support the application of the MMIS package including the following technologies that meet strengthened regulation requirements and enhanced utility's performance requirements to nuclear plants. - Dedication to real time operating system for safety-grade computers - V and V of the broadband communication network for safety information - Independent V and V for application of programmable logic controllers to nuclear plants - Development strategy for an integrated SW development tool for control devices

  9. Co-operation Equipment Qualification for Safety grade I and C Equipment between Russia and Korea

    International Nuclear Information System (INIS)

    Ham, J. K.; Lee, D. H.; Park, J. W.; Jeong, M. H.; Choi, Y. H.; Suh, J. J.; Jang, T. H.

    2007-06-01

    Equipment Qualification technology for I and C system on nuclear grade have been approved with accurate and safe for verifying and validation. It contributes to acknowledge of reliability and to review of user approval. Also it did not completely satisfied the requirement of Russia, it can be satisfied by bit of modification on design. It is expected to support the export of safety PLC to nuclear power plant. Proven EQ technology is required on the further markets of nuclear. Therefore, comparison test with foreign country is necessary to support the mutual accreditation of EQ for export of domestic products

  10. Co-operation Equipment Qualification for Safety grade I and C Equipment between Russia and Korea

    Energy Technology Data Exchange (ETDEWEB)

    Ham, J. K.; Lee, D. H.; Park, J. W.; Jeong, M. H.; Choi, Y. H.; Suh, J. J.; Jang, T. H. [Korea Testing Laboratory, Seoul (Korea, Republic of)

    2007-06-15

    Equipment Qualification technology for I and C system on nuclear grade have been approved with accurate and safe for verifying and validation. It contributes to acknowledge of reliability and to review of user approval. Also it did not completely satisfied the requirement of Russia, it can be satisfied by bit of modification on design. It is expected to support the export of safety PLC to nuclear power plant. Proven EQ technology is required on the further markets of nuclear. Therefore, comparison test with foreign country is necessary to support the mutual accreditation of EQ for export of domestic products.

  11. Development of Necessary Technology for Safety Grade I and C System

    International Nuclear Information System (INIS)

    Lee, Dong Young; Jang, Tong Il; Kim, Jung Tack

    2010-08-01

    Through KNICS and Nu-Tech 2012, a MMIS(Man-Machine Interface System) package for nuclear plants was localized and is expected to be applied to SUN 1,2 plants. This study is aimed to support the application of the MMIS package including the following technologies that meet strengthened regulation requirements and enhanced utility's performance requirements to nuclear plants. - Dedication to safety-grade computers - The broadband communication network for safety information - Application of the automatic test for safety systems - Application of programmable logic controllers to nuclear plant

  12. Fundamentals of a graded approach to safety-related equipment setpoints

    International Nuclear Information System (INIS)

    Woodruff, B.A.; Cash, J.S. Jr.; Bockhorst, R.M.

    1993-01-01

    The concept of using a graded approach to reconstitute instrument setpoints associated with safety-related equipment was first presented to the industry by the U.S. Nuclear Regulatory Commission during the 1992 ISA/POWID Symposium in Kansas City, Missouri. The graded approach establishes that the manner in which a utility analyzes and documents setpoints is related to each setpoint's relative importance to safety. This allows a utility to develop separate requirements for setpoints of varying levels of safety significance. A graded approach to setpoints is a viable strategy that minimizes extraneous effort expended in resolving difficult issues that arise when formal setpoint methodology is applied blindly to all setpoints. Close examination of setpoint methodology reveals that the application of a graded approach is fundamentally dependent on the analytical basis of each individual setpoint

  13. Technical Meeting on Grading of the Application of Management System Requirements. Presentations

    International Nuclear Information System (INIS)

    2012-01-01

    The objectives of this Technical Meeting are threefold: - to share international experiences and lessons learned, as well as exchange views on best practices and strategies to overcome the difficulties encountered; - to review and discuss the draft technical report on 'Grading the Application of Management System Requirements, to allow the participants to contribute to the improvement of the document and to enrich it with practical examples; and - to strengthen the international networking of specialists in the field. The topics covered during the meeting will include: - Examples and case studies presented by participants from countries with nuclear facilities (mainly focused on NPPs, and, where appropriate, from research reactors, fuel cycle and waste management facilities) on grading the application of management system requirements and lessons learned. - Reviewing and improving the final draft of a technical report on 'Grading the Application of Management System Requirements', which will supersede the previous guidance: Grading of Quality Assurance Requirement: A Manual (Technical Reports Series No. 328)

  14. Nuclear energy

    International Nuclear Information System (INIS)

    2007-01-01

    This digest document was written by members of the union of associations of ex-members and retired people of the Areva group (UARGA). It gives a comprehensive overview of the nuclear industry world, starting from radioactivity and its applications, and going on with the fuel cycle (front-end, back-end, fuel reprocessing, transports), the nuclear reactors (PWR, BWR, Candu, HTR, generation 4 systems), the effluents from nuclear facilities, the nuclear wastes (processing, disposal), and the management and safety of nuclear activities. (J.S.)

  15. Nuclear orientation and nuclear structure

    International Nuclear Information System (INIS)

    Krane, K.S.

    1988-01-01

    The present generation of on-line nuclear orientation facilities promises to revolutionize the gathering of nuclear structure information, especially for the hitherto poorly known and understood nuclei far from stability. Following a brief review of the technological developments that have facilitated these experiments, the nuclear spectroscopic information that can be obtained is summarized. Applications to understanding nuclear structure are reviewed, and challenges for future studies are discussed. (orig.)

  16. Nuclear power

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    The committee concludes that the nature of the proliferation problem is such that even stopping nuclear power completely could not stop proliferation completely. Countries can acquire nuclear weapons by means independent of commercial nuclear power. It is reasonable to suppose if a country is strongly motivated to acquire nuclear weapons, it will have them by 2010, or soon thereafter, no matter how nuclear power is managed in the meantime. Unilateral and international diplomatic measures to reduce the motivations that lead to proliferation should be high on the foreign policy agenda of the United States. A mimimum antiproliferation prescription for the management of nuclear power is to try to raise the political barriers against proliferation through misuse of nuclear power by strengthening the Non-Proliferation Treaty, and to seek to raise the technological barriers by placing fuel-cycle operations involving weapons-usable material under international control. Any such measures should be considered tactics to slow the spread of nuclear weapons and thus earn time for the exercise of statesmanship. The committee concludes the following about technical factors that should be considered in formulating nuclear policy: (1) rate of growth of electricity use is a primary factor; (2) growth of conventional nuclear power will be limited by producibility of domestic uranium sources; (3) greater contribution of nuclear power beyond 400 GWe past the year 2000 can only be supported by advanced reactor systems; and (4) several different breeder reactors could serve in principle as candidates for an indefinitely sustainable source of energy

  17. Nuclear physics

    International Nuclear Information System (INIS)

    Kamal, Anwar

    2014-01-01

    Explains the concepts in detail and in depth. Provides step-by-step derivations. Contains numerous tables and diagrams. Supports learning and teaching with numerous worked examples, questions and problems with answers. Sketches also the historical development of the subject. This textbook explains the experimental basics, effects and theory of nuclear physics. It supports learning and teaching with numerous worked examples, questions and problems with answers. Numerous tables and diagrams help to better understand the explanations. A better feeling to the subject of the book is given with sketches about the historical development of nuclear physics. The main topics of this book include the phenomena associated with passage of charged particles and radiation through matter which are related to nuclear resonance fluorescence and the Moessbauer effect., Gamov's theory of alpha decay, Fermi theory of beta decay, electron capture and gamma decay. The discussion of general properties of nuclei covers nuclear sizes and nuclear force, nuclear spin, magnetic dipole moment and electric quadrupole moment. Nuclear instability against various modes of decay and Yukawa theory are explained. Nuclear models such as Fermi Gas Model, Shell Model, Liquid Drop Model, Collective Model and Optical Model are outlined to explain various experimental facts related to nuclear structure. Heavy ion reactions, including nuclear fusion, are explained. Nuclear fission and fusion power production is treated elaborately.

  18. Nuclear chemistry

    International Nuclear Information System (INIS)

    Vertes, A.; Kiss, I.

    1987-01-01

    This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors

  19. Nuclear chemistry

    International Nuclear Information System (INIS)

    Vertes, A.; Kiss, I.

    1987-01-01

    This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors. (Auth.)

  20. Nuclear forensics

    International Nuclear Information System (INIS)

    Karadeniz, O.; Guenalp, G.

    2010-01-01

    This review discusses the methodology of nuclear forensics and illicit trafficking of nuclear materials. Nuclear forensics is relatively new scientific branch whose aim it is to read out material inherent from nuclear material. Nuclear forensics investigations have to be considered as part of a comprehensive set of measures for detection,interception, categorization and characterization of illicitly trafficking nuclear material. Prevention, detection and response are the main elements in combating illicit trafficking. Forensics is a key element in the response process. Forensic science is defined as the application of a broad spectrum of sciences to answer questions of interest to the legal system. Besides, in this study we will explain age determination of nuclear materials.

  1. Nuclear fuels

    International Nuclear Information System (INIS)

    Gangwani, Saloni; Chakrabortty, Sumita

    2011-01-01

    Nuclear fuel is a material that can be consumed to derive nuclear energy, by analogy to chemical fuel that is burned for energy. Nuclear fuels are the most dense sources of energy available. Nuclear fuel in a nuclear fuel cycle can refer to the fuel itself, or to physical objects (for example bundles composed of fuel rods) composed of the fuel material, mixed with structural, neutron moderating, or neutron reflecting materials. Long-lived radioactive waste from the back end of the fuel cycle is especially relevant when designing a complete waste management plan for SNF. When looking at long-term radioactive decay, the actinides in the SNF have a significant influence due to their characteristically long half-lives. Depending on what a nuclear reactor is fueled with, the actinide composition in the SNF will be different. The following paper will also include the uses. advancements, advantages, disadvantages, various processes and behavior of nuclear fuels

  2. Nuclear networking.

    Science.gov (United States)

    Xie, Wei; Burke, Brian

    2017-07-04

    Nuclear lamins are intermediate filament proteins that represent important structural components of metazoan nuclear envelopes (NEs). By combining proteomics and superresolution microscopy, we recently reported that both A- and B-type nuclear lamins form spatially distinct filament networks at the nuclear periphery of mouse fibroblasts. In particular, A-type lamins exhibit differential association with nuclear pore complexes (NPCs). Our studies reveal that the nuclear lamina network in mammalian somatic cells is less ordered and more complex than that of amphibian oocytes, the only other system in which the lamina has been visualized at high resolution. In addition, the NPC component Tpr likely links NPCs to the A-type lamin network, an association that appears to be regulated by C-terminal modification of various A-type lamin isoforms. Many questions remain, however, concerning the structure and assembly of lamin filaments, as well as with their mode of association with other nuclear components such as peripheral chromatin.

  3. World warms to nuclear power

    International Nuclear Information System (INIS)

    Mortimer, N.

    1989-01-01

    The greenhouse effect and global warming is a major environmental issue. The nuclear industry has taken this opportunity to promote itself as providing clean energy without implication in either the greenhouse effect or acid rain. However, it is acknowledged that nuclear power does have its own environment concerns. Two questions are posed -does nuclear power contribute to carbon dioxide emissions and can nuclear power provide a realistic long-term solution to global warming? Although nuclear power stations do not emit carbon dioxide, emissions occur during the manufacture of reactor components, the operation of the nuclear fuel cycle and especially, during the mining and processing of the uranium ore. It is estimated that the supply of high grade ores will last only 23 years, beyond that the carbon dioxide emitted during the processing is estimated to be as great as the carbon dioxide emitted from an coal-fired reactor. Fast breeder reactors are dismissed as unable to provide an answer, so it is concluded that nuclear technology has only a very limited role to play in countering global warming.(UK)

  4. Low grade uranium ores as potential sources of raw material

    International Nuclear Information System (INIS)

    Venzlaff, H.

    1976-01-01

    Reports on the uranium requirement and the uranium reserves show that, even if the demand were to be stretched out slightly, the rate of new discoveries of uranium would have to be doubled or even tripled within a few years in order to ensure supply. Despite some spectacular discoveries of large scale deposits in Australia it must be said that only very few truly new uranium provinces have been discovered over the past twenty years. In this situation more attention is now being devoted to low grade uranium depositis, to findings whose concentration does not exceed 1,000 ppm. These deposits contain quantities of uranium many times larger than the deposits that can now be mined at prices up to 30/lb of U 3 O 8 . Even now low grade uranium ore is being mined as a byproduct, with the actual valuable mineral producing most of the income from mining activities. However, if one strikes a balance in this situation, one finds that only part of the requirement can be met in this way. Hence, all possibilities must be exhausted to mine uranium as a byproduct, new techniques of uranium production from low grade ores must be developed, and also conventional prospection must be intensified, if the continuity of supply of the nuclear power stations in the eighties and nineties is to be guaranteed. (orig.) [de

  5. Is the Sky Falling? Grade Inflation and the Signaling Power of Grades.

    Science.gov (United States)

    Pattison, Evangeleen; Grodsky, Eric; Muller, Chandra

    2013-06-01

    Grades are the fundamental currency of our educational system; they signal academic achievement and non-cognitive skills to parents, employers, postsecondary gatekeepers, and students themselves. Grade inflation compromises the signaling value of grades, undermining their capacity to achieve the functions for which they are intended. We challenge the 'increases in grade point average' definition of grade inflation and argue that grade inflation must be understood in terms of the signaling power of grades. Analyzing data from four nationally representative samples, we find that in the decades following 1972: (a) grades have risen at high schools and dropped at four-year colleges, in general, and selective four-year institutions, in particular; and (b) the signaling power of grades has attenuated little, if at all.

  6. Production of Food Grade Yeasts

    Directory of Open Access Journals (Sweden)

    Argyro Bekatorou

    2006-01-01

    Full Text Available Yeasts have been known to humans for thousands of years as they have been used in traditional fermentation processes like wine, beer and bread making. Today, yeasts are also used as alternative sources of high nutritional value proteins, enzymes and vitamins, and have numerous applications in the health food industry as food additives, conditioners and flavouring agents, for the production of microbiology media and extracts, as well as livestock feeds. Modern scientific advances allow the isolation, construction and industrial production of new yeast strains to satisfy the specific demands of the food industry. Types of commercial food grade yeasts, industrial production processes and raw materials are highlighted. Aspects of yeast metabolism, with respect to carbohydrate utilization, nutritional aspects and recent research advances are also discussed.

  7. Nuclear blackmail and nuclear balance

    International Nuclear Information System (INIS)

    Betts, R.K.

    1987-01-01

    This book raises pointed questions about nuclear saber rattling. More than a dozen cases since the bombing of Hiroshima and Magasaki in which some sort of nuclear threat was used as a sparring technique in tense confrontations are cited. Each incident is described and analyzed. Two theories offered to explain America's use of nuclear threats, the balance of interest theory and the balance of power theory, are contrasted throughout the book. This book helps to fill the gap in the understanding of nuclear weapons and their uses, while pointing out that nuclear bravado could lead to an unintended unleashing of these weapons

  8. Processing of low-grade uranium ores

    International Nuclear Information System (INIS)

    Michel, P.

    1975-01-01

    Four types of low grade ores are studied. Low grade ores which must be extracted because they are enclosed in a normal grade deposit. Heap leaching is the processing method which is largely used. It allows to obtain solutions or preconcentrates which may be delivered at the nearest plant. Normal grade ores contained in a low amplitude deposit which can be processed using leaching as far as the operation does not need any large expensive equipment. Medium grade ores in medium amplitude deposits to which a simplified conventional process can be applied using fast heap leaching. Low grade ores in large deposits. The processing possibilities leading to use in place leaching are explained. The operating conditions of the method are studied (leaching agent, preparation of the ore deposit to obtain a good tightness with regard to the hydrological system and to have a good contact between ore and reagent) [fr

  9. Processing of low grade uranium ores

    International Nuclear Information System (INIS)

    Michel, P.

    1978-10-01

    Four types of low-grade ores are studied: (1) Low-grade ores that must be extracted because they are enclosed in a normal-grade deposit. Heap leaching is the processing method which is largely used. (2) Normal-grade ores contained in low-amplitude deposits. They can be processed using in-place leaching as far as the operation does not need any large and expensive equipment. (3) Medium-grade ores in medium-amplitude deposits. A simplified conventional process can be applied using fast heap leaching. (4) Low-grade ores in large deposits. The report explains processing possibilities leading in most cases to the use of in-place leaching. The operating conditions of this method are laid out, especially the selection of the leaching agents and the preparation of the ore deposit

  10. Nuclear energy and nuclear weapons

    International Nuclear Information System (INIS)

    Robertson, J.A.L.

    1983-06-01

    We all want to prevent the use of nuclear weapons. The issue before us is how best to achieve this objective; more specifically, whether the peaceful applications of nuclear energy help or hinder, and to what extent. Many of us in the nuclear industry are working on these applications from a conviction that without peaceful nuclear energy the risk of nuclear war would be appreciably greater. Others, however, hold the opposite view. In discussing the subject, a necessary step in allaying fears is understanding some facts, and indeed facing up to some unpalatable facts. When the facts are assessed, and a balance struck, the conclusion is that peaceful nuclear energy is much more part of the solution to preventing nuclear war than it is part of the problem

  11. Intralesional and metastatic heterogeneity in malignant melanomas demonstrated by stereologic estimates of nuclear volume

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Erlandsen, M

    1990-01-01

    Regional variability of nuclear 3-dimensional size can be estimated objectively using point-sampled intercepts obtained from different, defined zones within individual neoplasms. In the present study, stereologic estimates of the volume-weighted mean nuclear volume, nuclear vv, within peripheral...... melanomas showed large interindividual variation. This finding emphasizes that unbiased estimates of nuclear vv are robust to regional heterogeneity of nuclear volume and thus suitable for purposes of objective, quantitative malignancy grading of melanomas....

  12. The Harnessed Atom: Nuclear Energy & Electricity.

    Science.gov (United States)

    Department of Energy, Washington, DC. Nuclear Energy Office.

    This document is part of a nuclear energy curriculum designed for grades six through eight. The complete kit includes a written text, review exercises, activities for the students, and a teachers guide. The 19 lessons in the curriculum are divided into four units including: (1) "Energy and Electricity"; (2) "Understanding Atoms and Radiation"; (3)…

  13. Iran's nuclear program - for power generation or nuclear weapons?

    International Nuclear Information System (INIS)

    Kippe, Halvor

    2008-11-01

    This report addresses the development of a nuclear infrastructure in Iran, and assessments are made on the near-term potential this infrastructure might yield of either nuclear power or nuclear arms production. The most significant facilities are treated in a more elaborate fashion, as these are assumed to have key roles in either a true civilian programme, or in the prospect of weapons-grade fissile material production. The future potential capacity for the latter is calculated under certain presumptions, both in the case that Iran focuses its efforts on uranium-based nuclear weapons, and in the case that it should choose the plutonium path to nuclear weapons. All the conclusions and findings in this report are based on technological considerations. This means that social or political assessments have not prevailed, rather the picture of Iran's nuclear programme is drawn through descriptions and assessments of facilities and systems, and their role in the bigger context. Definite conclusions have not been made as to whether Iran's nuclear programme currently is aimed towards nuclear arms or nuclear power. The secrecy surrounding some of the most prominent nuclear sites together with more or less credible allegations of purely weapons-related activities in the past, make it hard not to conclude that Iran until the disclosures in 2002 made as great an effort as it could on its way on developing nuclear weapons covertly. The scope of today's nuclear programme seems, on the other hand, most likely to be in part to help relieve the ever-increasing need for energy, although considerable deficits to this strategy are identified, at the same time as the Iranian people are united in a giant, high-prestige project in defiance of massive international pressure. Adding to this is a much-feared ability to rapidly being able to redirect their nuclear efforts, and develop nuclear arms in perhaps as little as one year. This so-called break-out scenario, where Iran presumably

  14. MRI differentiation of low-grade from high-grade appendicular chondrosarcoma

    International Nuclear Information System (INIS)

    Douis, Hassan; Singh, Leanne; Saifuddin, Asif

    2014-01-01

    To identify magnetic resonance imaging (MRI) features which differentiate low-grade chondral lesions (atypical cartilaginous tumours/grade 1 chondrosarcoma) from high-grade chondrosarcomas (grade 2, grade 3 and dedifferentiated chondrosarcoma) of the major long bones. We identified all patients treated for central atypical cartilaginous tumours and central chondrosarcoma of major long bones (humerus, femur, tibia) over a 13-year period. The MRI studies were assessed for the following features: bone marrow oedema, soft tissue oedema, bone expansion, cortical thickening, cortical destruction, active periostitis, soft tissue mass and tumour length. The MRI-features were compared with the histopathological tumour grading using univariate, multivariate logistic regression and receiver operating characteristic curve (ROC) analyses. One hundred and seventy-nine tumours were included in this retrospective study. There were 28 atypical cartilaginous tumours, 79 grade 1 chondrosarcomas, 36 grade 2 chondrosarcomas, 13 grade 3 chondrosarcomas and 23 dedifferentiated chondrosarcomas. Multivariate analysis demonstrated that bone expansion (P = 0.001), active periostitis (P = 0.001), soft tissue mass (P < 0.001) and tumour length (P < 0.001) were statistically significant differentiating factors between low-grade and high-grade chondral lesions with an area under the ROC curve of 0.956. On MRI, bone expansion, active periostitis, soft tissue mass and tumour length can reliably differentiate high-grade chondrosarcomas from low-grade chondral lesions of the major long bones. (orig.)

  15. MRI differentiation of low-grade from high-grade appendicular chondrosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Douis, Hassan; Singh, Leanne; Saifuddin, Asif [The Royal National Orthopaedic Hospital NHS Trust, Department of Radiology, Stanmore, Middlesex (United Kingdom)

    2014-01-15

    To identify magnetic resonance imaging (MRI) features which differentiate low-grade chondral lesions (atypical cartilaginous tumours/grade 1 chondrosarcoma) from high-grade chondrosarcomas (grade 2, grade 3 and dedifferentiated chondrosarcoma) of the major long bones. We identified all patients treated for central atypical cartilaginous tumours and central chondrosarcoma of major long bones (humerus, femur, tibia) over a 13-year period. The MRI studies were assessed for the following features: bone marrow oedema, soft tissue oedema, bone expansion, cortical thickening, cortical destruction, active periostitis, soft tissue mass and tumour length. The MRI-features were compared with the histopathological tumour grading using univariate, multivariate logistic regression and receiver operating characteristic curve (ROC) analyses. One hundred and seventy-nine tumours were included in this retrospective study. There were 28 atypical cartilaginous tumours, 79 grade 1 chondrosarcomas, 36 grade 2 chondrosarcomas, 13 grade 3 chondrosarcomas and 23 dedifferentiated chondrosarcomas. Multivariate analysis demonstrated that bone expansion (P = 0.001), active periostitis (P = 0.001), soft tissue mass (P < 0.001) and tumour length (P < 0.001) were statistically significant differentiating factors between low-grade and high-grade chondral lesions with an area under the ROC curve of 0.956. On MRI, bone expansion, active periostitis, soft tissue mass and tumour length can reliably differentiate high-grade chondrosarcomas from low-grade chondral lesions of the major long bones. (orig.)

  16. Peer Victimization in Fifth Grade and Health in Tenth Grade

    Science.gov (United States)

    Elliott, Marc N.; Klein, David J.; Tortolero, Susan R.; Mrug, Sylvie; Peskin, Melissa F.; Davies, Susan L.; Schink, Elizabeth T.; Schuster, Mark A.

    2014-01-01

    BACKGROUND AND OBJECTIVES: Children who experience bullying, a type of peer victimization, show worse mental and physical health cross-sectionally. Few studies have assessed these relationships longitudinally. We examined longitudinal associations of bullying with mental and physical health from elementary to high school, comparing effects of different bullying histories. METHODS: We analyzed data from 4297 children surveyed at 3 time points (fifth, seventh, and tenth grades) in 3 cities. We used multivariable regressions to test longitudinal associations of bullying with mental and physical health by comparing youth who experienced bullying in both the past and present, experienced bullying in the present only, experienced bullying in the past only, or did not experience bullying. RESULTS: Bullying was associated with worse mental and physical health, greater depression symptoms, and lower self-worth over time. Health was significantly worse for children with both past and present bullying experiences, followed by children with present-only experiences, children with past-only experiences, and children with no experiences. For example, 44.6% of children bullied in both the past and present were at the lowest decile of psychosocial health, compared with 30.7% of those bullied in the present only (P = .005), 12.1% of those bullied in the past only (P bullied (P bullying are associated with substantially worse health. Clinicians who recognize bullying when it first starts could intervene to reverse the downward health trajectory experienced by youth who are repeated targets. PMID:24534401

  17. Nuclear materials

    International Nuclear Information System (INIS)

    1996-01-01

    In 1998, Nuclear Regulatory Authority of the Slovak Republic (NRA SR) performed 38 inspections, 25 of them were performed in co-operation with IAEA inspectors. There is no fresh nuclear fuel at Bohunice A-1 NPP at present. Fresh fuel of Bohunice V-1 and V-2 NPPs is inspected in the fresh fuel storage.There are 327 fresh fuel assemblies in Mochovce NPP fresh fuel storage. In addition to that, are also 71 small users of nuclear materials in Slovakia. In most cases they use: covers made of depleted uranium for non-destructive works, detection of level in production plants, covers for therapeutical sources at medical facilities. In. 1995, NRA SR issued 4 new licences for nuclear material withdrawal. In the next part manipulation with nuclear materials, spent fuel stores and illegal trafficking in nuclear materials are reported

  18. Nuclear Law

    International Nuclear Information System (INIS)

    Wiesbauer, Bruno

    1978-01-01

    This book is the first attempt of a comprehensive compilation of national Austrian Nuclear Law (Nuclear Liability Act; Radiation protection Act, Radiation Protection Ordinance, Security Control Act, Act on the uses of Nuclear Energy - Zwentendorf Nuclear Power Plant) and the most important international agreements to which Austria is a party. Furthermore, the book contains the most important Nuclear Liability Conventions to which Austria is not yet a party, but which are applicable in neighbouring; the Paris Convention served as a model for the national Nuclear Liability Act and may be used for its interpretation. The author has translated a number of international instruments into German, such as the Expose des Motifs of the Paris Convention. (NEA) [fr

  19. Nuclear nonproliferation

    International Nuclear Information System (INIS)

    Neubert, M.

    1992-01-01

    The following motion was put before the United Kingdom House of Commons on 3rd February 1992 and agreed; that this House, recognising the potential dangers of the rapidly changing world order, welcomes the recent proposals for substantial reductions in nuclear weaponry, the growing support for the non-proliferation treaty and progress in the implementation of the United Nations Security Council Resolutions concerning the dismantling of Iraqi nuclear, chemical and biological capabilities; urges the Government to play their full part in helping the relevant authorities in the Commonwealth of Independent States to dismantle their nuclear devices, to safeguard their nuclear components and to discourage the proliferation of nuclear expertise; and believes it is of the first importance that Britain retains an effective and credible minimum nuclear deterrent as security in a world where there remain many sources of instability. The record of arguments for and against the motion in the debate is presented. (author)

  20. Nuclear energy

    International Nuclear Information System (INIS)

    Panait, A.

    1994-01-01

    This is a general report presenting the section VII entitled Nuclear Power of the National Conference on Energy (CNE '94) held in Neptun, Romania, on 13-16 June 1994. The problems addressed were those relating to electric power produced by nuclear power plant, to heat secondary generation, to quality assurance, to safety, etc. A special attention was paid to the commissioning of the first Romanian nuclear power unit, the Cernavoda-1 reactor of CANDU type. The communications were grouped in four subsections. These were: 1. Quality assurance, nuclear safety, and environmental protection; 2. Nuclear power plant, commissioning, and operation; 3. Nuclear power plant inspection, maintenance, and repairs, heavy water technology; 4. Public opinion education. There were 22 reports, altogether

  1. Nuclear power

    International Nuclear Information System (INIS)

    King, P.

    1990-01-01

    Written from the basis of neutrality, neither for nor against nuclear power this book considers whether there are special features of nuclear power which mean that its development should be either promoted or restrained by the State. The author makes it dear that there are no easy answers to the questions raised by the intervention of nuclear power but calls for openness in the nuclear decision making process. First, the need for energy is considered; most people agree that energy is the power to progress. Then the historicalzed background to the current position of nuclear power is given. Further chapters consider the fuel cycle, environmental impacts including carbon dioxide emission and the greenhouse effect, the costs, safety and risks and waste disposal. No conclusion either for or against nuclear power is made. The various shades of opinion are outlined and the arguments presented so that readers can come to their own conclusions. (UK)

  2. Nuclear power

    International Nuclear Information System (INIS)

    Porter, Arthur.

    1980-01-01

    This chapter of the final report of the Royal Commission on Electric Power Planning in Ontario updates its interim report on nuclear power in Ontario (1978) in the light of the Three Mile Island accident and presents the commission's general conclusions and recommendations relating to nuclear power. The risks of nuclear power, reactor safety with special reference to Three Mile Island and incidents at the Bruce generating station, the environmental effects of uranium mining and milling, waste management, nuclear power economics, uranium supplies, socio-political issues, and the regulation of nuclear power are discussed. Specific recommendations are made concerning the organization and public control of Ontario Hydro, but the commission concluded that nuclear power is acceptable in Ontario as long as satisfactory progress is made in the disposal of uranium mill tailings and spent fuel wastes. (LL)

  3. Nuclear science and engineering education at a university research reactor

    International Nuclear Information System (INIS)

    Loveland, W.

    1990-01-01

    The research and teaching operations of the Nuclear Chemistry Division of the Dept. of Chemistry and the Dept. of Nuclear Engineering are housed at the Oregon State University Radiation Center. This facility which includes a 1.1 MW TRIGA reactor was used for 53 classes from a number of different academic departments last year. About one-half of these classes used the reactor and ∼25% of the reactor's 45 hour week was devoted to teaching. Descriptions will be given of reactor-oriented instructional programs in nuclear engineering, radiation health and nuclear chemistry. In nuclear chemistry, classes in (a) nuclear chemistry for nuclear engineers, (b) radiotracer methods, (c) elementary and advanced activation analysis, and (d) advanced nuclear instrumentation will be described in detail. The use of the facility to promote general nuclear literacy among college students, high school and grade school students and the general population will also be covered

  4. Nuclear astrophysics

    International Nuclear Information System (INIS)

    Haxton, W.C.

    1992-01-01

    The problem of core-collapse supernovae is used to illustrate the many connections between nuclear astrophysics and the problems nuclear physicists study in terrestrial laboratories. Efforts to better understand the collapse and mantle ejection are also motivated by a variety of interdisciplinary issues in nuclear, particle, and astrophysics, including galactic chemical evolution, neutrino masses and mixing, and stellar cooling by the emission of new particles. The current status of theory and observations is summarized

  5. Nuclear physics

    International Nuclear Information System (INIS)

    Patel, S.B.

    1991-01-01

    This book is a simple and direct introduction to the tools of modern nuclear physics, both experimental and mathematical. Emphasizes physical intuition and illuminating analogies, rather than formal mathematics. Topics covered include particle accelerators, radioactive series, types of nuclear reactions, detection of the neutrino, nuclear isomerism, binding energy of nuclei, fission chain reactions, and predictions of the shell model. Each chapter contains problems and illustrative examples. Pre-requisites are calculus and elementary vector analysis

  6. Nuclear energy

    International Nuclear Information System (INIS)

    Hesketh, Ross.

    1985-01-01

    The subject is treated under the headings: nuclear energy -what is it; fusion (principles; practice); fission (principles); reactor types and systems (fast (neutron) reactors as breeders; fast reactors; thermal reactors; graphite-moderated thermal reactors; the CANDU reactor; light water reactors - the BWR and the PWR); the nuclear fuel cycle (waste storage; fuel element manufacture; enrichment processes; uranium mining); safety and risk assessment; the nuclear power industry and the economy (regulating authorities; economics; advantages and disadvantages). (U.K.)

  7. Chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade plutonium nitrate solutions

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    These analytical procedures are designed to show whether a given material meets the purchaser's specifications as to plutonium content, effective fissile content, and impurity content. The following procedures are described in detail: plutonium by controlled-potential coulometry; plutonium by amperometric titration with iron(II); free acid by titration in an oxalate solution; free acid by iodate precipitation-potentiometric titration method; uranium by Arsenazo I spectrophotometric method; thorium by thorin spectrophotometric method; iron by 1,10-phenanthroline spectrophotometric method; chloride by thiocyanate spectrophotometric method; fluoride by distillation-spectrophotometric method; sulfate by barium sulfate turbidimetric method; isotopic composition by mass spectrometry; americium-241 by extraction and gamma counting; americium-241 by gamma counting; gamma-emitting fission products, uranium, and thorium by gamma-ray spectroscopy; rare earths by copper spark spectrochemical method; tungsten, niobium (columbium), and tantalum by spectrochemical method; simple preparation by spectrographic analysis for general impurities

  8. Software V and V methods for a safety - grade programmable logic controller

    International Nuclear Information System (INIS)

    Jang Yeol Kim; Young Jun Lee; Kyung Ho Cha; Se Woo Cheon; Jang Soo Lee; Kee Choon Kwon

    2006-01-01

    This paper addresses the Verification and Validation(V and V) process and the methodology for an embedded real time software of a safety-grade Programmable Logic Controller(PLC). This safety- grade PLC is being developed as one of the Korean Nuclear Instrumentation and Control System (KNICS) projects. KNICS projects are developing a Reactor Protection System(RPS) and an Engineered Safety Feature-Component Control System(ESF-CCS) as well as a safety-grade PLC. The safety-grade PLC will be a major component that encomposes the RPS systems and the ESF-CCS systems as nuclear instruments and control equipment. This paper describes the V and V guidelines and procedures, V and V environment, V and V process and methodology, and the V and V tools in the KNICS projects. Specifically, it describes the real-time operating system V and V experience which corresponds to the requirement analysis phase, design phase and the implementation and testing phase of the software development life cycle. Main activities of the V and V for the PLC system software are a technical evaluation, licensing suitability evaluation, inspection and traceability analysis, formal verification, software safety analysis, and a software configuration management. The proposed V and V methodology satisfies the Standard Review Plan(SRP)/Branch Technical Position(BTP)-14 criteria for the safety software in nuclear power plants. The proposed V and V methodology is going to be used to verify the upcoming software life cycle in the KNICS projects. (author)

  9. Equipment Qualification and Environment Establishment for COTS Dedication of Safety Grade PC

    International Nuclear Information System (INIS)

    Ahn, Kwang Chul; Bin, Chang Sun; Kwon, Yoon Kwang; Kang, Shin Woo; Koh, Sung Won; Shon, Eui Chan; Jang, Hyun Doo; Song, Il Sup; Lee, Hyun Noh

    2010-08-01

    Safety grade PCs are required for protection systems of SKN 3 and 4 nuclear power plant and subsequent plants. Commercial grade item (CGI) dedication should be carried out to utilize a commercial PC as a safety grade PC of nuclear power plants. This project is aimed to perform the equipment qualification of the commercial PC, and review and improve the quality system of the PC supplier. As a result of the EQ for the CGI dedication, selected military PCs have passed the environment test, the seismic test, and the EMI test required for the digital controllers of nuclear plants. In addition, a walk-through of the quality system of the PC supplier, ISO 9001, was carried out and the quality system was improved. History data for the PC was gathered. As the analysis of the history data showed that operating experience time of the PC is longer than the plant life time, the history data could be used as an evidence of acceptance. After dedicated according to the CGI dedication process, military rugged PCs could be used for safety grade PCs

  10. Nuclear Asia

    National Research Council Canada - National Science Library

    Ferguson, Joseph; Tarleton, Gael

    2004-01-01

    .... This event was an opportunity for policy makers, security analysts, nuclear scientists and engineers, regional experts, and military planners to share perspectives and identify those issues requiring...

  11. Nuclear cardiology

    International Nuclear Information System (INIS)

    Fish, M.B.

    2002-01-01

    Recent advances in nuclear medicine instrumentation and software, including myocardial perfusion imaging, offer increased accuracy in the detection, diagnosis and prognosis of coronary artery disease. (orig.)

  12. Nuclear medicine

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    The area of nuclear medicine, the development of artificially produced radioactive isotopes for medical applications, is relatively recent. Among the subjects covered in a lengthy discussion are the following: history of development; impact of nuclear medicine; understanding the most effective use of radioisotopes; most significant uses of nuclear medicine radioimmunoassays; description of equipment designed for use in the field of nuclear medicine (counters, scanning system, display systems, gamma camera); description of radioisotopes used and their purposes; quality control. Numerous historical photographs are included. 52 refs

  13. Nuclear Law

    International Nuclear Information System (INIS)

    Pascal, Maurice.

    1979-01-01

    This book on nuclear law is the first of a series of analytical studies to be published by the French Energy Commission (CEA) concerning all the various nuclear activities. It describes national and international legislation applicable in France covering the following main sectors: the licensing procedure for nuclear installations, the law of the sea and nuclear law, the legal system governing radioisotopes, the transport of radioactive materials, third party liability and insurance and radiation protection. In each chapter, the overall analysis is supplemented by the relevant regulatory texts and by organisation charts in annex. (NEA) [fr

  14. Nuclear Safety

    Energy Technology Data Exchange (ETDEWEB)

    Silver, E G [ed.

    1989-01-01

    This document is a review journal that covers significant developments in the field of nuclear safety. Its scope includes the analysis and control of hazards associated with nuclear energy, operations involving fissionable materials, and the products of nuclear fission and their effects on the environment. Primary emphasis is on safety in reactor design, construction, and operation; however, the safety aspects of the entire fuel cycle, including fuel fabrication, spent-fuel processing, nuclear waste disposal, handling of radioisotopes, and environmental effects of these operations, are also treated.

  15. Nuclear power

    International Nuclear Information System (INIS)

    Bupp, I.C.

    1991-01-01

    Is a nuclear power renaissance likely to occur in the United States? This paper investigates the many driving forces that will determine the answer to that question. This analysis reveals some frequently overlooked truths about the current state of nuclear technology: An examination of the issues also produces some noteworthy insights concerning government regulations and related technologies. Public opinion will play a major role in the unfolding story of the nuclear power renaissance. Some observers are betting that psychological, sociological, and political considerations will hod sway over public attitudes. Others wager that economic and technical concerns will prevail. The implications for the nuclear power renaissance are striking

  16. What's in a Grade? Grading Policies and Practices in Principles of Economics

    Science.gov (United States)

    Walstad, William B.; Miller, Laurie A.

    2016-01-01

    Survey results from a national sample of economics instructors describe the grading policies and practices in principles of economics courses. The survey results provide insights about absolute and relative grading systems used by instructors, the course components and their weights that determine grades, and the type of assessment items used for…

  17. Teachers grading practices : an analysis of the reliability of teacher-assigned grade point average (GPA)

    NARCIS (Netherlands)

    van der Lans, R. M.; van de Grift, W. J. C. M.; van Veen, K.

    2015-01-01

    In previous research, teachers report that they use a hodgepodge of factors when grading students. This has led researchers to suspect that teacher-assigned grades are inflated by teacher-student interactions; the hodgepodge hypothesis. Teachers also are reported to differ in grading leniency; the

  18. The Impact of Early Exposure of Eighth Grade Math Standards on End of Grade Assessments

    Science.gov (United States)

    Robertson, Tonjai E.

    2016-01-01

    The purpose of this study was to examine the Cumberland County Schools district-wide issue surrounding the disproportional performance of eighth grade Math I students' proficiency scores on standardized end-of-grade and end-of-course assessments. The study focused on the impact of the school district incorporating eighth grade math standards in…

  19. Are Flunkers Social Outcasts? A Multilevel Study of Grade Retention Effects on Same-Grade Friendships

    Science.gov (United States)

    Demanet, Jannick; Van Houtte, Mieke

    2016-01-01

    We examine the association between grade retention and the number of same-grade friendships. Moreover, we investigate the effect of a school's proportion of retained students on these friendships and the moderating effect of this school characteristic on the relationship between retention and the number of same-grade friendships. Multilevel…

  20. Nuclear stress test

    Science.gov (United States)

    ... Persantine stress test; Thallium stress test; Stress test - nuclear; Adenosine stress test; Regadenoson stress test; CAD - nuclear stress; Coronary artery disease - nuclear stress; Angina - nuclear ...

  1. Fifth Grade Elementary Students' Conceptions of Earthquakes

    Science.gov (United States)

    Savasci, Funda; Uluduz, Hatice

    2013-01-01

    This study intends to investigate the fifth grade students' conceptions of earthquakes. Twenty two grade 5 students (11-12 years old) from five different elementary schools in Istanbul voluntarily participated in the study. Data were collected from semi-structured interviews with each participant. Six interview questions were designed by…

  2. Matriculation Research Report: Incomplete Grades; Data & Analysis.

    Science.gov (United States)

    Gerda, Joe

    The policy on incomplete grades at California's College of the Canyons states that incompletes may only be given under circumstances beyond students' control and that students must make arrangements with faculty prior to the end of the semester to clear the incomplete. Failure to complete an incomplete may result in an "F" grade. While…

  3. The Leap into 4th Grade

    Science.gov (United States)

    Anderson, Mike

    2011-01-01

    Fourth grade is a pivotal year, in which students commonly face increased academic demands. According to Anderson, teachers can help students make a smooth transition to 4th grade by introducing these new challenges in ways that are in line with 4th graders' common developmental characteristics: incredible energy and emotion, industriousness and…

  4. Bruxism defined and graded: an international consensus

    NARCIS (Netherlands)

    Lobbezoo, F.; Ahlberg, J.; Glaros, A.G.; Kato, T.; Koyano, K.; Lavigne, G.J.; de Leeuw, R.; Manfredini, D.; Svensson, P.; Winocur, E.

    2013-01-01

    To date, there is no consensus about the definition and diagnostic grading of bruxism. A written consensus discussion was held among an international group of bruxism experts as to formulate a definition of bruxism and to suggest a grading system for its operationalisation. The expert group defined

  5. Perceptions of restaurateurs on quality grading

    Directory of Open Access Journals (Sweden)

    Joseph Roberson

    2014-01-01

    Full Text Available A restaurateur's strategic focus is to maximise wealth for the owner(s. To achieve wealth maximisation, a restaurateur could implement one or more of the following strategies: focus strategy, cost-leadership strategy and/or differentiation strategy. A management intervention a restaurateur could implement to achieve this is quality differentiation. Grading of an establishment will assist a restaurateur in becoming a market leader. Currently there no national restaurant grading system exists in South Africa. As support and participation of restaurateurs in any future quality grading system are essential, it is imperative to test their perceptions of the implementation of a quality grading scale. The aim of this paper is to gather the perceptions of restaurateurs of an envisaged scale that could be used to grade independent full-service restaurants. In this study the researcher tested the perceptions of restaurateurs using nine possible outcomes of implementing quality grading in the independent fullservice restaurant segment. The outcomes to be tested were presented to restaurateurs in a questionnaire uploaded on "survey monkey". This was emailed to 3 286 restaurateurs and 265 responses were received. Respondents who were positive regarding grading indicated that they were enthusiastic about the impact grading would have on international tourism, as well as the fact that it could contribute to an increase in the value of their establishments.

  6. 7 CFR 51.2556 - Grades.

    Science.gov (United States)

    2010-01-01

    ... Standards for Grades of Shelled Pistachio Nuts § 51.2556 Grades. (a) “U.S. Fancy,” “U.S. Extra No. 1,” and “U.S. No. 1” consist of pistachio kernels which meet the following requirements: (1) Well dried, or...

  7. Contraction of graded su(2) algebra

    International Nuclear Information System (INIS)

    Patra, M.K.; Tripathy, K.C.

    1989-01-01

    The Inoenu-Wigner contraction scheme is extended to Lie superalgebras. The structure and representations of extended BRS algebra are obtained from contraction of the graded su(2) algebra. From cohomological consideration, we demonstrate that the graded su(2) algebra is the only superalgebra which, on contraction, yields the full BRS algebra. (orig.)

  8. What's ahead in automated lumber grading

    Science.gov (United States)

    D. Earl Kline; Richard Conners; Philip A. Araman

    1998-01-01

    This paper discusses how present scanning technologies are being applied to automatic lumber grading. The presentation focuses on 1) what sensing and scanning devices are needed to measure information for accurate grading feature detection, 2) the hardware and software needed to efficiently process this information, and 3) specific issues related to softwood lumber...

  9. Liberal Grading Improves Evaluations But Not Performance.

    Science.gov (United States)

    Vasta, Ross; Sarmiento, Robert F.

    Two grading distributions--a liberal and a more stringent curve--were compared between two sections of an undergraduate psychology course. The two classes were team taught and treated as similarly as possible. Four unit exams and an optional final were administered, with one section consistently receiving a more lenient grade distribution. No…

  10. Examining First Grade Teachers' Handwriting Instruction

    Science.gov (United States)

    Arslan, Derya

    2012-01-01

    The purpose of this study is to examine the first grade teachers' practices of handwriting instructions in terms of teaching, evaluation and handwriting difficulties. From qualitative research patterns, phenomenology was used. The study was applied to the 54 First grade teachers who work at central Burdur and Burdur county centre primary education…

  11. Extrauterine Low-Grade Endometrial Stromal Sarcoma

    Directory of Open Access Journals (Sweden)

    Yu-Ju Chen

    2005-12-01

    Conclusions: Low-grade endometrial stromal sarcoma typically has an indolent clinical course and favorable prognosis. Surgical resection is the primary therapeutic approach, and adjuvant therapy with radiotherapy, chemotherapy, or progesterone therapy should be considered for the management of residual or recurrent low-grade endometrial stromal sarcomas.

  12. Grade Repetition in Queensland State Prep Classes

    Science.gov (United States)

    Anderson, Robyn

    2012-01-01

    The current study considers grade repetition rates in the early years of schooling in Queensland state schools with specific focus on the pre-schooling year, Prep. In particular, it provides empirical evidence of grade repetition in Queensland state schools along with groups of students who are more often repeated. At the same time, much of the…

  13. Consumer Preference for Graded Maple Syrup

    Science.gov (United States)

    Paul E. Sendak

    1978-01-01

    The three grades of maple syrup and a commercial table syrup containing artificial flavor and 3 percent pure maple syrup were evaluated by 1,018 women in four cities. The results indicate that differences in preference for flavor are related to how close the respondents are to a maple syrup-production region. Differences in preference among grades of pure maple syrup...

  14. Determinants of College Grade Point Averages

    Science.gov (United States)

    Bailey, Paul Dean

    2012-01-01

    Chapter 2: The Role of Class Difficulty in College Grade Point Averages. Grade Point Averages (GPAs) are widely used as a measure of college students' ability. Low GPAs can remove a students from eligibility for scholarships, and even continued enrollment at a university. However, GPAs are determined not only by student ability but also by the…

  15. Grading sugar pine saw logs in trees.

    Science.gov (United States)

    John W. Henley

    1972-01-01

    Small limbs and small overgrown limbs cause problems when grading saw logs in sugar pine trees. Surface characteristics and lumber recovery information for 426 logs from 64 sugar pine trees were examined. Resulting modifications in the grading specification that allow a grader to ignore small limbs and small limb indicators do not appear to decrease the performance of...

  16. Nuclear physics for nuclear fusion

    International Nuclear Information System (INIS)

    Li Xingzhong; Liu Bin; Wei Qingming; Ren Xianzhe

    2004-01-01

    The D-T fusion cross-section is calculated using quantum mechanics with the model of square nuclear potential well and Coulomb potential barrier. The agreement between ENDF data and the theoretically calculated results is well in the range of 0.2-280 keV. It shows that the application of Breit-Wigner formula is not suitable for the case of the light nuclei fusion reaction. When this model is applied to the nuclear reaction between the charged particles confined in a lattice, it explains the 'abnormal phenomena'. It implies a prospect of nuclear fusion energy without strong nuclear radiations

  17. Graded activity: legacy of the sanatorium.

    Science.gov (United States)

    Creighton, C

    1993-08-01

    Occupational therapists in all areas of practice grade therapeutic activities to help patients progress toward their goals. It is proposed in this paper that the concept of graded activity originated in German tuberculosis sanatoria in the late 1800s, when patients were required to walk on graded (sloped) land for exercise. British physician Marcus Paterson included work, as well as walking, in his graduated exercise program for tuberculosis patients and was honored for this innovation at the founding meeting of the National Society for the Promotion of Occupational Therapy (NSPOT). George Barton, Susan Tracy, and Herbert Hall were among the NSPOT members who contributed to the development of graded activity as a principle in occupational therapy intervention. The military rehabilitation programs established during World War I provided additional impetus, and by the mid-1920s, graded activity was recognized as central to the profession.

  18. Functionally Graded Adhesives for Composite Joints

    Science.gov (United States)

    Stapleton, Scott E.; Waas, Anthony M.; Arnold, Steven M.

    2012-01-01

    Adhesives with functionally graded material properties are being considered for use in adhesively bonded joints to reduce the peel stress concentrations located near adherend discontinuities. Several practical concerns impede the actual use of such adhesives. These include increased manufacturing complications, alterations to the grading due to adhesive flow during manufacturing, and whether changing the loading conditions significantly impact the effectiveness of the grading. An analytical study is conducted to address these three concerns. An enhanced joint finite element, which uses an analytical formulation to obtain exact shape functions, is used to model the joint. Furthermore, proof of concept testing is conducted to show the potential advantages of functionally graded adhesives. In this study, grading is achieved by strategically placing glass beads within the adhesive layer at different densities along the joint.

  19. Foraminal syringomyelia: suggestion for a grading system.

    Science.gov (United States)

    Versari, P P; D'Aliberti, G; Talamonti, G; Collice, M

    1993-01-01

    The standard treatment of foraminal syringomyelia includes foramen magnum decompression and duraplasty. Improvement or stabilization of the disease are achieved in most of cases. However, at least one third of patients are reported to receive little or no benefit. In this paper we retrospectively reviewed a series of 40 consecutive foramen magnum decompressions in order to identify the possible pre-operative outcome predictors. Based on clinical evolution, neurological impairment and radiological features, a scale of severity was fixed and retrospectively tested. A pre-operative score was obtained for each patient and was correlated with the surgical results. Then a four level grading system was derived. All grade I and grade II patients achieved good results (improvement or stabilization), whereas grade III patients showed intermediate behaviour and grade IV invariably worsened. On this basis, surgical results of foramen magnum decompression might be further improved provided that a careful pre-operative selection is made.

  20. Nuclear installations

    International Nuclear Information System (INIS)

    2001-01-01

    This document presents the fulfilling of the Brazilian obligations under the Convention on Nuclear Safety. The Chapter 2 of the document contains some details about the existing Brazilian nuclear installations. Also, safety improvements at Angra 1 and aspects of Angra 2 and 3 are reported

  1. Nuclear safety

    International Nuclear Information System (INIS)

    1991-02-01

    This book reviews the accomplishments, operations, and problems faced by the defense Nuclear Facilities Safety Board. Specifically, it discusses the recommendations that the Safety Board made to improve safety and health conditions at the Department of Energy's defense nuclear facilities, problems the Safety Board has encountered in hiring technical staff, and management problems that could affect the Safety Board's independence and credibility

  2. Nuclear violence

    International Nuclear Information System (INIS)

    Mullen, R.K.

    1987-01-01

    A great deal of attention has been paid in the past decade or so to the characteristics of terrorists and their apparent goals and objectives, capabilities, and evolving strategy and tactics with respect to nuclear terrorism. In contrast, little has been said about the procedural aspects of nuclear terrorism, and even less about the way in which such endeavors can fail. This latter omission is important because it bears directly on the ability to evaluate credibly the potential for nuclear terrorism. Here, the author addresses the requirements inherent in acquiring a nuclear explosive capability by three routes: separation of plutonium from irradiated light or heavy water reactor (LWR or HWR) fuel, processing, or use of separated fissile material, and theft of a nuclear weapon. In addition, he deals with other potential acts of nuclear terrorism: sabotage of power reactors, uranium enrichment facilities and spent nuclear fuel in transport, and dispersal of radioactive materials, in particular, plutonium. He specifically does not look at the design or production of a nuclear weapon. Finally, the discussion here assumes that the terrorist is subnational; that is, a nation is not involved. Also, the discussion of subnational participation does not address the possibility of collusion with insiders

  3. Nuclear installations

    International Nuclear Information System (INIS)

    1998-01-01

    This document presents the fulfilling of the Brazilian obligations under the Convention on Nuclear Safety. The Chapter 2 of the document contains some details about the existing Brazilian nuclear installations. Also, safety improvements at Angra 1 and aspects of Angra 2 and 3 are reported

  4. Nuclear power

    International Nuclear Information System (INIS)

    Abd Khalik Wood

    2003-01-01

    This chapter discuss on nuclear power and its advantages. The concept of nucleus fission, fusion, electric generation are discussed in this chapter. Nuclear power has big potential to become alternative energy to substitute current conventional energy from coal, oil and gas

  5. Nuclear energy

    International Nuclear Information System (INIS)

    1978-01-01

    This brochure is intended as a contribution to a better and more general understanding of one of the most urgent problems of present society. Emphasis is laid on three issues that are always raised in the nuclear debate: 1) Fuel cycle, 2) environmental effects of nuclear power plants, 3) waste disposal problems. (GL) [de

  6. Nuclear pollution

    International Nuclear Information System (INIS)

    Ramade, Francois

    1979-01-01

    In this chapter devoted to nuclear pollution the following topics were studied: fundamentals of radiobiology (ecological importance of the various radioisotopes, biological effects of ionizing radiations); ecological effects of radioactive fallout (contamination of atmosphere, terrestrial ecosystems, oceans). The electronuclear industry and its environmental impact. PWR type reactors, fuel reprocessing plants, contamination of trophic chains by radionuclides released in the environment from nuclear installations [fr

  7. Nuclear lifetimes

    International Nuclear Information System (INIS)

    Caraca, J.M.G.

    1976-01-01

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

  8. Nuclear facts

    International Nuclear Information System (INIS)

    1982-01-01

    The subject is discussed as follows: the case for using nuclear energy (Britain's energy needs; energy policy); safety; transport of spent fuel; radiation (natural radioactivity); environment (land use of nuclear power plants; storage and disposal of radioactive wastes). (U.K.)

  9. Nuclear measurements

    International Nuclear Information System (INIS)

    Schenkel, R.

    2005-01-01

    Nuclear measurements play a fundamental role in the development of nuclear technology and the assurance of its peaceful use. They are also required in many non-power nuclear applications such as in nuclear medicine, agriculture, environmental protection, etc. This presentation will show examples of most recent advances in measurement methodology or technology in the areas described below. The Generation IV International Forum has selected six innovative reactor systems as candidates for a next generation of sustainable, economic and safe nuclear energy systems. The choice of the best options relies heavily on the availability of accurate nuclear data that can only be obtained, in an international effort, using highly specialised facilities. Significant efforts are being directed towards the partitioning and transmutation of highly active nuclear waste. Different concepts involving fast reactors or accelerator-driven systems are being studied in view of their transmutation capabilities. State of the art equipment has been developed to assess basic properties of nuclear fuel at very high burn-up; some fine examples of this work will be shown. Physical and chemical methods play a crucial role in the detection and identification of radioisotopes used in various stages of the nuclear fuel cycle. Radiation measurement techniques are used, for example, to monitor the quantities of uranium, plutonium and other actinide elements in fuel enrichment and reprocessing facilities. Another field of application of physical and chemical methods is the characterisation of nuclear material seized from illicit trafficking. Seized material has to be analysed in order to obtain clues on its origin and intended use and to prevent diversion of nuclear material from the same source in the future. A recent highlight in basic physics relates to nuclear fission and transmutation with high intensity lasers. Ultra-fast high intensity lasers can produce high energy (tens of MeV) photons through

  10. Nuclear rockets

    International Nuclear Information System (INIS)

    Sarram, M.

    1972-01-01

    Nuclear energy has found many applications in space projects. This article deals with these applications. The first application is the use of nuclear energy for the production of electricity in space and the second main application is the use of nuclear energy for propulsion purposes in space flight. The main objective is to develop a 75000 pound thrust flight engine call NERVA by heating liquid hydrogen, in a nuclear reactor, from 420F to 4000 0 F. The paper describes in detail the salient features of the NERVA rocket as well as its comparison with the conventional chemical rockets. It is shown that a nuclear rocket using liquid hydrogen as medium is at least 85% more efficient as compared with the chemical rockets such as those used for the APOLLO moon flight

  11. Nuclear rockets

    Energy Technology Data Exchange (ETDEWEB)

    Sarram, M [Teheran Univ. (Iran). Inst. of Nuclear Science and Technology

    1972-02-01

    Nuclear energy has found many applications in space projects. This article deals with these applications. The first application is the use of nuclear energy for the production of electricity in space and the second main application is the use of nuclear energy for propulsion purposes in space flight. The main objective is to develop a 75000 pound thrust flight engine called NERVA by heating liquid hydrogen in a nuclear reactor. The paper describes in detail the salient features of the NERVA rocket as well as its comparison with the conventional chemical rockets. It is shown that a nuclear rocket using liquid hydrogen as medium is at least 85% more efficient as compared with the chemical rockets such as those used for the APOLLO moon flight.

  12. Nuclear haematology

    International Nuclear Information System (INIS)

    Masjhur, J.S.

    1992-01-01

    Nuclear techniques have been applied to study diagnose and treat various haematological disorders for more than five decades. Two scientists are regarded as pioneers in this field, i.e. John Lawrence who in 1938 used 32 P to treat chronic myeloid leukaemia and George Hevessy who used 32 P labelled erythrocytes to measure blood volume in 1939. At present, many nuclear medicine procedures are available for diagnosis and therapy of a variety of haematological disorders. Although nuclear techniques are somewhat complex, they give direct and quantitative assessment of the kinetics of blood elements as compared to other non-isotopic haematological tests. Basically, equipment required for nuclear haematology is very simple such as well scintillation counters to measure radioactivity in blood samples. More sophisticated equipment like rectilinear scanner or gamma camera is required when imaging is necessary. An overview of the basic principles and clinical applications of nuclear haematology is given

  13. Nuclear forensics

    International Nuclear Information System (INIS)

    Venugopal, V.

    2010-01-01

    Increasing threat by terrorists for a possible nuclear attack is particularly alarming in recent years. The likelihood of such an event is highly uncertain but cannot be ruled out. The consequence of such an event would be highly disastrous and the implications could be far-reaching both socially and politically. It is feared that significant amount of nuclear weapons materials may be kept under poor security. Therefore, there is a greater demand with utmost priority to curb nuclear terrorism by adapting proper security measures. One of the most important measures is to stop illicit trafficking of nuclear materials which are the source of building nuclear explosive devices. According to the IAEA illicit trafficking database (ITDB) report, a total number of 252 incidents were reported in 2006, of which 150 occurred in 2006 and the remaining 102 had taken place prior to that year, mainly in 2005

  14. Nuclear Safety

    International Nuclear Information System (INIS)

    1978-09-01

    In this short paper it has only been possible to deal in a rather general way with the standards of safety used in the UK nuclear industry. The record of the industry extending over at least twenty years is impressive and, indeed, unique. No other industry has been so painstaking in protection of its workers and in its avoidance of damage to the environment. Headings are: introduction; how a nuclear power station works; radiation and its effects (including reference to ICRP, the UK National Radiological Protection Board, and safety standards); typical radiation doses (natural radiation, therapy, nuclear power programme and other sources); safety of nuclear reactors - design; key questions (matters of concern which arise in the public mind); safety of operators; safety of people in the vicinity of a nuclear power station; safety of the general public; safety bodies. (U.K.)

  15. Nuclear proliferation

    International Nuclear Information System (INIS)

    Stencel, S.

    1978-01-01

    The terms and reactions to President Carter's nuclear policy, culminating in the 1978 Nuclear Non-Proliferation Act, are reviewed and analyzed. The new law increases restrictions on nuclear exports, encourages continued use of light water reactors in preference to plutonium-fueled reactors, and emphasizes technical solutions to proliferation problems. Critics of the law point out that it will hurt U.S. trade unfairly, that other countries do not have as many fuel options as the U.S. has, and that nuclear sales have as many political and economic as technical solutions. Compromise areas include new international safety guidelines, the possibility of an international nuclear fuel bank, and a willingness to consider each case on its merits. 21 references

  16. Nuclear privatization

    International Nuclear Information System (INIS)

    Jeffs, E.

    1995-01-01

    The United Kingdom government announced in May 1995 plans to privatize the country's two nuclear generating companies, Nuclear Electric and Scottish Nuclear. Under the plan, the two companies will become operating divisions of a unified holding company, to be called British Electric, with headquarters in Scotland. Britain's nuclear plants were left out of the initial privatization in 1989 because the government believed the financial community would be unwilling to accept the open-ended liability of decommissioning the original nine stations based on the Magnox gas-cooled reactor. Six years later, the government has found a way around this by retaining these power stations in state ownership, leaving the new nuclear company with the eight Advanced Gas-cooled Reactor (AGR) stations and the recently completed Sizewell B PWR stations. The operating Magnox stations are to be transferred to BNFL, which operates two Magnox stations of their own at Calder Hall and Chapelcross

  17. Nuclear haematology

    Energy Technology Data Exchange (ETDEWEB)

    Masjhur, J S

    1993-12-31

    Nuclear techniques have been applied to study diagnose and treat various haematological disorders for more than five decades. Two scientists are regarded as pioneers in this field, i.e. John Lawrence who in 1938 used {sup 32}P to treat chronic myeloid leukaemia and George Hevessy who used {sup 32}P labelled erythrocytes to measure blood volume in 1939. At present, many nuclear medicine procedures are available for diagnosis and therapy of a variety of haematological disorders. Although nuclear techniques are somewhat complex, they give direct and quantitative assessment of the kinetics of blood elements as compared to other non-isotopic haematological tests. Basically, equipment required for nuclear haematology is very simple such as well scintillation counters to measure radioactivity in blood samples. More sophisticated equipment like rectilinear scanner or gamma camera is required when imaging is necessary. An overview of the basic principles and clinical applications of nuclear haematology is given

  18. The threat of nuclear terrorism

    International Nuclear Information System (INIS)

    Maerli, M.

    2001-01-01

    , the essential components of any nuclear weapon. State nuclear weapons programs will usually be supported by large and costly infrastructure for enrichment and/or reprocessing of fissile weapons material. Sub-national groups, however, are more likely to rely on externally acquired weapons-usable materials. The vast production of fissile materials during the cold war has today left the world with a staggering legacy of three million kilos of weapons-usable material. More than half of the overall production of weapons-usable materials is in excess of national security needs. The huge quantities of fissile materials and the numerous reports of lax security and accountancy of nuclear materials raise concerns over the possibility of a successful diversion of significant quantities of weapons-usable materials, particularly in the former Soviet Union. Recently declassified U.S. documents reveals that a significant nuclear yield can be accomplished by utilizing reactor-grade plutonium in nuclear explosives. Claims have been made that reactor-grade plutonium is a more appealing option to terrorists. Ever increasing stockpiles of separated civilian plutonium could thus be a reason for concern, and calls have been made to protect the material as if it were nuclear weapons. The use of crude nuclear weapons provides the opportunity of fairly reliable, distinct, prestigious, novel, and highly visible acts of large-scale terrorism. Preventing any extremist group for achieving their goals of large-scale nuclear violence could only be done by preventing the access to fissile materials through state compliance to rigorous standards of MPC and A. (author)

  19. Automated tone grading of granite

    International Nuclear Information System (INIS)

    Catalina Hernández, J.C.; Fernández Ramón, G.

    2017-01-01

    The production of a natural stone processing plant is subject to the intrinsic variability of the stone blocks that constitute its raw material, which may cause problems of lack of uniformity in the visual appearance of the produced material that often triggers complaints from customers. The best way to tackle this problem is to classify the product according to its visual features, which is traditionally done by hand: an operator observes each and every piece that comes out of the production line and assigns it to the closest match among a number of predefined classes, taking into account visual features of the material such as colour, texture, grain, veins, etc. However, this manual procedure presents significant consistency problems, due to the inherent subjectivity of the classification performed by each operator, and the errors caused by their progressive fatigue. Attempts to employ automated sorting systems like the ones used in the ceramic tile industry have not been successful, as natural stone presents much higher variability than ceramic tiles. Therefore, it has been necessary to develop classification systems specifically designed for the treatment of the visual parameters that distinguish the different types of natural stone. This paper describes the details of a computer vision system developed by AITEMIN for the automatic classification of granite pieces according to their tone, which provides an integral solution to tone grading problems in the granite processing and marketing industry. The system has been designed to be easily trained by the end user, through the learning of the samples established as tone patterns by the user. [es

  20. Nuclear questions

    Energy Technology Data Exchange (ETDEWEB)

    Durrani, M. [Physics World (United Kingdom)

    2006-01-01

    The future of nuclear power has returned to centre stage. Freezing weather on both sides of the Atlantic and last month's climate-change talks in Montreal have helped to put energy and the future of nuclear power right back on the political agenda. The issue is particularly pressing for those countries where existing nuclear stations are reaching the end of their lives. In the UK, prime minister Tony Blair has commissioned a review of energy, with a view to deciding later this year whether to build new nuclear power plants. The review comes just four years after the Labour government published a White Paper on energy that said the country should keep the nuclear option open but did not follow this up with any concrete action. In Germany, new chancellor and former physicist Angela Merkel is a fan of nuclear energy and had said she would extend the lifetime of its nuclear plants beyond 2020, when they are due to close. However, that commitment has had to be abandoned, at least for the time being, following negotiations with her left-wing coalition partners. The arguments in favour of nuclear power will be familiar to all physicists - it emits almost no carbon dioxide and can play a vital role in maintaining a diverse energy supply. To over-rely on imported supplies of oil and gas can leave a nation hostage to fortune. The arguments against are equally easy to list - the public is scared of nuclear power, it generates dangerous waste with potentially huge clean-up costs, and it is not necessarily cheap. Nuclear plants could also be a target for terrorist attacks. Given political will, many of these problems can be resolved, or at least tackled. China certainly sees the benefits of nuclear power, as does Finland, which is building a new 1600 MW station - the world's most powerful - that is set to open in 2009. Physicists, of course, are essential to such developments. They play a vital role in ensuring the safety of such plants and developing new types of

  1. Statistical theory of precompound nuclear reactions

    International Nuclear Information System (INIS)

    Nishioka, H.

    1986-01-01

    The purpose of the paper is to show the application of the Grassmann-integration method (or the graded-symmetry method) to a pre-equilibrium process in nuclear reactions. The Grassmann-integration method for random systems was first introduced by Efetov and later largely extended and applied to nuclear physics by Verbaarschot, Weidenmuller and Zirnbauer (referred to as VWZ). They have applied it to the equilibrium nuclear reactions; namely; the compound-nucleus reactions. It will be shown in this paper that this method is also applicable to non-equilibrium nuclear reactions. Applying this method to precompound nuclear reactions, the authors have obtained the same expression of the cross-section as Agassi, Weidenmuller and Mantzouranis (referred to as AWM) in the weak-coupling limit. In the general case their results show an important modification to AWM

  2. Nuclear Security Recommendations on Nuclear and other Radioactive Material out of Regulatory Control: Recommendations (Spanish Edition)

    International Nuclear Information System (INIS)

    2012-01-01

    This publication presents recommendations for the nuclear security of nuclear and other radioactive material that is out of regulatory control. It is based on national experiences and practices and guidance publications in the field of security as well as the nuclear security related international instruments. The recommendations include guidance for States with regard to the nuclear security of nuclear and other radioactive material that has been reported as being out of regulatory control as well as for material that is lost, missing or stolen but has not been reported as such, or has been otherwise discovered. In addition, these recommendations adhere to the detection and assessment of alarms and alerts and to a graded response to criminal or unauthorized acts with nuclear security implications.

  3. Nuclear Security Recommendations on Nuclear and Other Radioactive Material out of Regulatory Control: Recommendations (Arabic Edition)

    International Nuclear Information System (INIS)

    2012-01-01

    This publication presents recommendations for the nuclear security of nuclear and other radioactive material that is out of regulatory control. It is based on national experiences and practices and guidance publications in the ? field of security as well as the nuclear security related international instruments. The recommendations include guidance for States with regard to the nuclear security of nuclear and other radioactive material that has been reported as being out of regulatory control as well as for material that is lost, missing or stolen but has not been reported as such, or has been otherwise discovered. In addition, these recommendations adhere to the detection and assessment of alarms and alerts and to a graded response to criminal or unauthorized acts with nuclear security implications.

  4. Dangers associated with civil nuclear power programmes: weaponization and nuclear waste.

    Science.gov (United States)

    Boulton, Frank

    2015-07-24

    The number of nuclear power plants in the world rose exponentially to 420 by 1990 and peaked at 438 in 2002; but by 2014, as closed plants were not replaced, there were just 388. In spite of using more renewable energy, the world still relies on fossil fuels, but some countries plan to develop new nuclear programmes. Spent nuclear fuel, one of the most dangerous and toxic materials known, can be reprocessed into fresh fuel or into weapons-grade materials, and generates large amounts of highly active waste. This article reviews available literature on government and industry websites and from independent analysts on world energy production, the aspirations of the 'new nuclear build' programmes in China and the UK, and the difficulties in keeping the environment safe over an immense timescale while minimizing adverse health impacts and production of greenhouse gases, and preventing weaponization by non-nuclear-weapons states acquiring civil nuclear technology.

  5. Nuclear Security Recommendations on Nuclear and Other Radioactive Material out of Regulatory Control: Recommendations

    International Nuclear Information System (INIS)

    2011-01-01

    This publication presents recommendations for the nuclear security of nuclear and other radioactive material that is out of regulatory control. It is based on national experiences and practices and guidance publications in the field of security as well as the nuclear security related international instruments. The recommendations include guidance for States with regard to the nuclear security of nuclear and other radioactive material that has been reported as being out of regulatory control as well as for material that is lost, missing or stolen but has not been reported as such, or has been otherwise discovered. In addition, these recommendations adhere to the detection and assessment of alarms and alerts and to a graded response to criminal or unauthorized acts with nuclear security implications

  6. Nuclear Security Recommendations on Nuclear and Other Radioactive Material out of Regulatory Control: Recommendations (Russian Edition)

    International Nuclear Information System (INIS)

    2011-01-01

    This publication presents recommendations for the nuclear security of nuclear and other radioactive material that is out of regulatory control. It is based on national experiences and practices and guidance publications in the field of security as well as the nuclear security related international instruments. The recommendations include guidance for States with regard to the nuclear security of nuclear and other radioactive material that has been reported as being out of regulatory control as well as for material that is lost, missing or stolen but has not been reported as such, or has been otherwise discovered. In addition, these recommendations adhere to the detection and assessment of alarms and alerts and to a graded response to criminal or unauthorized acts with nuclear security implications.

  7. Microstructural characterization and pore structure analysis of nuclear graphite

    International Nuclear Information System (INIS)

    Kane, J.; Karthik, C.; Butt, D.P.; Windes, W.E.; Ubic, R.

    2011-01-01

    Graphite will be used as a structural and moderator material in next-generation nuclear reactors. While the overall nature of the production of nuclear graphite is well understood, the historic nuclear grades of graphite are no longer available. This paper reports the virgin microstructural characteristics of filler particles and macro-scale porosity in virgin nuclear graphite grades of interest to the Next Generation Nuclear Plant program. Optical microscopy was used to characterize filler particle size and shape as well as the arrangement of shrinkage cracks. Computer aided image analysis was applied to optical images to quantitatively determine the variation of pore structure, area, eccentricity, and orientation within and between grades. The overall porosity ranged between ∼14% and 21%. A few large pores constitute the majority of the overall porosity. The distribution of pore area in all grades was roughly logarithmic in nature. The average pore was best fit by an ellipse with aspect ratio of ∼2. An estimated 0.6-0.9% of observed porosity was attributed to shrinkage cracks in the filler particles. Finally, a preferred orientation of the porosity was observed in all grades.

  8. Nuclear energy

    International Nuclear Information System (INIS)

    Rippon, S.

    1984-01-01

    Do we need nuclear energy. Is it safe. What are the risks. Will it lead to proliferation. The questions are endless, the answers often confused. In the vigorous debates that surround the siting and operation of nuclear power plants, it is all too easy to lose sight of the central issues amid the mass of arguments and counter-arguments put forward. And there remains the doubt, who do we believe. This book presents the facts, simply, straightforwardly, and comprehensibly. It describes the different types of nuclear reactor, how they work, how energy is produced and transformed into usable power, how nuclear waste is handled, what safeguards are built in to prevent accident, contamination and misuse. More important, it does this in the context of the real world, examining the benefits as well as the dangers of a nuclear power programme, quantifying the risks, and providing an authoritative account of the nuclear industry worldwide. Technically complex and politically controversial, the contribution of nuclear energy to our future energy requirements is a crucial topic of our time. (author)

  9. GRADE INFLATION: An Issue for Higher Education?

    Directory of Open Access Journals (Sweden)

    Donald L. CARUTH,

    2013-01-01

    Full Text Available Grade inflation impacts university credibility, student courses of study, choices of institution, and other areas. There has been an upward shift in grades without a corresponding upward shift in knowledge gained. Some of the most frequently mentioned causes of grade inflation are: Ø student evaluations of professors, Ø student teacher dynamics, Ø merit-based financial aid, and Ø student expectations. Ø Among the reasons for higher student grades on the part of professors are: Ø fear of student evaluations, Ø avoidance of bad relations with students, Ø below average teaching skills,Ø lack of experience, Ø a lack of clearly stated objectives, and Ø job security. While grades are not a perfect answer to assessing student performance in a course they are still the best answer we have for evaluating students. In order to evaluate students more accurately, universities must identify the problems in grading and grading practices. Once this is accomplished new practices can be designed and policies implemented.

  10. Power calculation of grading device in desintegrator

    Science.gov (United States)

    Bogdanov, V. S.; Semikopenko, I. A.; Vavilov, D. V.

    2018-03-01

    This article describes the analytical method of measuring the secondary power consumption, necessitated by the installation of a grading device in the peripheral part of the grinding chamber in the desintegrator. There is a calculation model for defining the power input of the disintegrator increased by the extra power demand, required to rotate the grading device and to grind the material in the area between the external row of hammers and the grading device. The work has determined the inertia moments of a cylindrical section of the grading device with armour plates. The processing capacity of the grading device is adjusted to the conveying capacity of the auger feeder. The grading device enables one to increase the concentration of particles in the peripheral part of the grinding chamber and the amount of interaction between particles and armour plates as well as the number of colliding particles. The perforated sections provide the output of the ground material with the proper size granules, which together with the effects of armour plates, improves the efficiency of grinding. The power demand to rotate the grading device does not exceed the admissible value.

  11. Alternative Grading Systems. The Practitioner, Vol. III, No. 3.

    Science.gov (United States)

    De Leonibus, Nancy; Thomson, Scott

    After examining some of the pros and cons of traditional grading, the demands colleges make on grading practices, and the responses of people interested in grading, a number of examples of operating alternative systems are given. The alternatives include a dual (pass/withdraw grading in some courses, traditional grading in others) system, a…

  12. 7 CFR 51.1578 - Off-Grade potatoes.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Off-Grade potatoes. 51.1578 Section 51.1578... STANDARDS) United States Consumer Standards for Potatoes Off-Grade § 51.1578 Off-Grade potatoes. Potatoes which fail to meet the requirements of any of the foregoing grades shall be Off-Grade potatoes...

  13. Nuclear Hostages

    International Nuclear Information System (INIS)

    Cooper, C.L.

    1978-01-01

    The global spread of nuclear reactors for the production of energy seems inevitable. Nuclear power plants will be supplied--if not by the United States, then by one of several other exporters. But other aspects of this development are less certain. One is the relationship between proliferation of nuclear energy plants and that of nuclear weapons. Another is the actual constraint that such vulnerable potential targets as nuclear power plants would have on would-be aggressors. In the last analysis, this would depend on the rationality of a nation's leadership. What can be said for the concept of nuclear power plants as potential hostages is that by installing a reactor on its territory, a country increases its vulnerability to grave, possibly unacceptable damage in the event of war. As a result, that nation's leaders might be inclined to raise the threshold of their sensitivity to provocation by neighbors and to restrain their own inclinations toward aggression. Admittedly this is a frail substitute for robust international agreements, but in the present order of things it is not a trivial consideration. Many incidents once regarded by the great powers as easi belli have more recently been either resolved by diplomacy or ignored altogether. The idea must not be pressed too far. The export of a nuclear power plant to a Third World country cannot be advocated simply as a means to constrain its own military adventurism. Aside from the promise of a vast increase in energy supply for developing nations, nuclear powered generating stations could actually improve relations among countries. The risk of widespread radioactive contamination by nuclear power plants hit by even conventional bombs could introduce a positive new element into the military calculations of powers outside the NATO-Warsaw Pact arena. As they balance military and diplomatic solutions to local conflicts, moderation rather than bellicosity might become the better part of valor

  14. Nuclear medicine

    International Nuclear Information System (INIS)

    Kand, Purushottam

    2012-01-01

    Nuclear medicine is a specialized area of radiology that uses very small amounts of radioactive materials to examine organ function and structure. Nuclear medicine is older than CT, ultrasound and MRI. It was first used in patients over 60-70 years ago. Today it is an established medical specialty and offers procedures that are essential in many medical specialities like nephrology, pediatrics, cardiology, psychiatry, endocrinology and oncology. Nuclear medicine refers to medicine (a pharmaceutical) that is attached to a small quantity of radioactive material (a radioisotope). This combination is called a radiopharmaceutical. There are many radiopharmaceuticals like DTPA, DMSA, HIDA, MIBI and MDP available to study different parts of the body like kidneys, heart and bones etc. Nuclear medicine uses radiation coming from inside a patient's body where as conventional radiology exposes patients to radiation from outside the body. Thus nuclear imaging study is a physiological imaging, whereas diagnostic radiology is anatomical imaging. It combines many different disciplines like chemistry, physics mathematics, computer technology, and medicine. It helps in diagnosis and to treat abnormalities very early in the progression of a disease. The information provides a quick and accurate diagnosis of wide range of conditions and diseases in a person of any age. These tests are painless and most scans expose patients to only minimal and safe amounts of radiation. The amount of radiation received from a nuclear medicine procedure is comparable to, or often many times less than, that of a diagnostic X-ray. Nuclear medicine provides an effective means of examining whether some tissues/organs are functioning properly. Therapy using nuclear medicine in an effective, safe and relatively inexpensive way of controlling and in some cases eliminating, conditions such as overactive thyroid, thyroid cancer and arthritis. Nuclear medicine imaging is unique because it provides doctors with

  15. Nuclear inheritance

    International Nuclear Information System (INIS)

    Delpech, Therese

    1997-01-01

    Since the end of the East-West confronting, the nuclear weapon issue has been focused in an international debate with obvious repercussions in Europe, because it is the European continent which indicated first the significance of nuclear deterrence. This debate refers first upon the past, as the German unification allowed capturing numerous documents of Warsaw treaty which revealed the intentions and the plans of Soviet Union during the cold war, and secondly concerns the future, since the role of nuclear weapons must be re-thought in a new context. This is the subject of this book, which refers also to the problem of the nuclear proliferation in the world and evolution of different countries in a political and regional context. The extension of the non-proliferation treaty for an undefined duration, in May 1995, is a incontestable victory because this treaty rules the renouncement to nuclear weapons of 185 countries. However, it does not solve most sensible problems like the Iraq case, for which a specific inspection regime has been instituted, or the case of Iran, which is suspected to acquire the bomb, although no clear evidence has been provided up to now. This is also the case of Israel, India and Pakistan which allege plainly their willingness of keeping open, from security reasons, their nuclear option. The content is displayed in five chapters: 1. Introduction; 2. The role of the nuclear weapons after the cold war; 3. The nuclear proliferation at crossroads; 4. Undefined extension of the NPT, a striking but fragile victory; 5. Conclusions. An appendix containing the text of the Nuclear Weapon Non-Proliferation Treaty and a chronology are added

  16. Atypical nuclear localization of VIP receptors in glioma cell lines and patients

    Energy Technology Data Exchange (ETDEWEB)

    Barbarin, Alice; Séité, Paule [Equipe Récepteurs, Régulations et Cellules Tumorales, Université de Poitiers, PBS bât 36, 1 rue Georges Bonnet, TSA 51106, 86073 Poitiers Cedex 9 (France); Godet, Julie [Laboratoire d’anatomie et de cytologie pathologiques, CHU de Poitiers, 2 rue de la Milétrie, 86000 Poitiers (France); Bensalma, Souheyla; Muller, Jean-Marc [Equipe Récepteurs, Régulations et Cellules Tumorales, Université de Poitiers, PBS bât 36, 1 rue Georges Bonnet, TSA 51106, 86073 Poitiers Cedex 9 (France); Chadéneau, Corinne, E-mail: corinne.chadeneau@univ-poitiers.fr [Equipe Récepteurs, Régulations et Cellules Tumorales, Université de Poitiers, PBS bât 36, 1 rue Georges Bonnet, TSA 51106, 86073 Poitiers Cedex 9 (France)

    2014-11-28

    Highlights: • The VIP receptor VPAC1 contains a putative NLS signal. • VPAC1 is predominantly nuclear in GBM cell lines but not VPAC2. • Non-nuclear VPAC1/2 protein expression is correlated with glioma grade. • Nuclear VPAC1 is observed in 50% of stage IV glioma (GBM). - Abstract: An increasing number of G protein-coupled receptors, like receptors for vasoactive intestinal peptide (VIP), are found in cell nucleus. As VIP receptors are involved in the regulation of glioma cell proliferation and migration, we investigated the expression and the nuclear localization of the VIP receptors VPAC1 and VPAC2 in this cancer. First, by applying Western blot and immunofluorescence detection in three human glioblastoma (GBM) cell lines, we observed a strong nuclear staining for the VPAC1 receptor and a weak nuclear VPAC2 receptor staining. Second, immunohistochemical staining of VPAC1 and VPAC2 on tissue microarrays (TMA) showed that the two receptors were expressed in normal brain and glioma tissues. Expression in the non-nuclear compartment of the two receptors significantly increased with the grade of the tumors. Analysis of nuclear staining revealed a significant increase of VPAC1 staining with glioma grade, with up to 50% of GBM displaying strong VPAC1 nuclear staining, whereas nuclear VPAC2 staining remained marginal. The increase in VPAC receptor expression with glioma grades and the enhanced nuclear localization of the VPAC1 receptors in GBM might be of importance for glioma progression.

  17. Nuclear energy

    International Nuclear Information System (INIS)

    Hladky, S.

    1985-01-01

    This booklet appeared in a series on technical history. It tries to communicate some of the scientific, technical and social stresses, which have been connected with the application of nuclear energy since its discovery. The individual sections are concerned with the following subjects: the search for the 'smallest particles'; the atomic nucleus; nuclear fission; the 'Manhattan Project'; the time after this - from the euphoria of the 1950's via disillusionment and change of opinion to the state of nuclear energy at the start of the 1980's. The booklet contains many details and is generously illustrated. (HSCH) [de

  18. Nuclear transport

    International Nuclear Information System (INIS)

    Anon.

    2003-01-01

    During january and february 2003, a unique event concerning nuclear transport was reported and rated 1 on the INES scale. This event concerns the absence of a maintenance operation on a shipping cask. This shipping cask was used for several years for nuclear transport inside La-hague site before being re-assigned to transport on public thoroughfare. The re-assignment of the cask should have been preceded and conditioned by a maintenance operation whose purpose is to check the efficiency of its radiation shield. During this period 2 on-site inspections concerning the transport of nuclear materials were performed. (A.C.)

  19. Nuclear energy

    International Nuclear Information System (INIS)

    Luxo, Armand.

    1977-01-01

    The reasons and conditions of utilizing nuclear power in developing countries are examined jointly with the present status and future uses already evaluated by some organizations. Some consequences are deduced in the human, financial scientific and technological fields, with provisional suggestions for preparing the nuclear industry development in these countries. As a conclusion trends are given to show how the industrialized countries having gained a long scientific and technological experience in nuclear energy can afford their assistance in this field, to developing countries [fr

  20. Nuclear questions

    International Nuclear Information System (INIS)

    Hohlfeld, W.

    1977-01-01

    This brochure 'nuclear problems' deals with the attitude of the protestant church in the region around the northern Elbe towards further quantitative economic growth, esp. nuclear energy, with the following essays: preaching the Gospel in an environment in danger: the Christian occident and the problems of the third world, facing the problems of exhausted supplies, the role of the prophet, problem of environment - a problem of theology, the political dimension, against ATW, signal Brokdorf, strange effects (defense of the church from unqualified teachings by non-professionals), Christian liberty, church and nuclear energy, violence and robes. (HP) [de

  1. Rotterdam Nuclear

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    In 1965 Rotterdam Nuclear received an order for the design, supply of materials, manufacture, testing, inspection and preparation for shipment of one 450MW Boiling Water Reactor pressure vessel. This was one of the first orders for a reactor pressure vessel, ever obtained by a European Manufacturer. The Company has since supplied 19 reactor pressure vessels for nuclear power stations, having a total weight of about 10,000,000kg. The nuclear power stations in which these are installed represent an electrical output of about 15,000MW and they are located in seven different countries (USA, Spain, Switzerland, Argentina, Sweden, Germany and the Netherlands). (Auth.)

  2. Nuclear law

    International Nuclear Information System (INIS)

    Bringuier, P.

    2009-01-01

    The object of this report is to present the evolution of the nuclear law during the period from 2006 to 2008, period that was characterized in France by a real rewriting from the implementation of a control authority. The prescriptive backing of nuclear activities has been deeply changed by numerous texts. In this first part are presented: (1) the institutional aspects, (2) openness and public information, (7) radioactive wastes and (9) liability and insurance. In a next publication will be treated: (3) safety and radiation protection; (4) nuclear matter, inspection, physical protection; (5) transports; (6) trade, non-proliferation; (8) radiological accidents. (N.C.)

  3. Nuclear fuel

    International Nuclear Information System (INIS)

    D Hondt, P.

    1998-01-01

    The research and development programme on nuclear fuel at the Belgian Nuclear Research Centre SCK/CEN is described. The objective of this programme is to enhance the quantitative prediction of the operational limits of nuclear fuel and to assess the behaviour of fuel under incidental and accidental conditions. Progress is described in different domains including the modelling of fission gas release in LWR fuel, thermal conductivity, basic physical phenomena, post-irradiation examination for fuel performance assessment, and conceptual studies of incidental and accidental fuel experiments

  4. Nuclear energy

    International Nuclear Information System (INIS)

    Wethe, Per Ivar

    2009-01-01

    Today we know two forms of nuclear energy: fission and fusion. Fission is the decomposition of heavy nuclei, while fusion is the melting together of light nuclei. Both processes create a large surplus of energy. Technologically, we can currently only use fission to produce energy in today's nuclear power plants, but there is intense research worldwide in order to realize a controlled fusion process. In a practical context, today's nuclear energy is a sustained source of energy since the resource base is virtually unlimited. When fusion technology is realized, the resource supply will be a marginal problem. (AG)

  5. Nuclear electronics

    International Nuclear Information System (INIS)

    Lucero B, E.

    1989-01-01

    The rapid technical development of Colombia over the past years, resulted among others, a considerable increase in the number of measuring instrumentation and testing laboratories, scientific research and metrology centers, in industry, agriculture, public health, education on the nuclear field, etc. IAN is a well organized institution with qualified management, trained staff and reasonably equipped laboratories to carry out tasks as: Metrology, standardization, quality control and maintenance and repair of nuclear instruments. The government of Colombia has adopted a policy to establish and operate through the country maintenance and repair facilities for nuclear instrumentation. This policy is reflected in the organization of electronic laboratories in Bogota-IAN

  6. Asymmetric acoustic transmission in graded beam

    Energy Technology Data Exchange (ETDEWEB)

    Jing, Li, E-mail: lj94172350@hotmail.com [School of Mechanical Engineering and State Key laboratory for Strength and Vibration of Mechanical Structures, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China); Wu, Jiu Hui, E-mail: ejhwu@mail.xjtu.edu.cn [School of Mechanical Engineering and State Key laboratory for Strength and Vibration of Mechanical Structures, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China); Guan, Dong; Lu, Kuan [School of Mechanical Engineering and State Key laboratory for Strength and Vibration of Mechanical Structures, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China); Gao, Nansha [School of Marine Science and Technology, Northwestern Polytechnical University, Xi’an, Shaanxi 710072 (China); Songhua, Cao [School of Mechanical Engineering and State Key laboratory for Strength and Vibration of Mechanical Structures, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China)

    2016-12-01

    We demonstrate the dynamic effective material parameters and vibration performance of a graded beam. The structure of the beam was composed of several unit cells with different fill factors. The dispersion relations and energy band structures of each unit cell were calculated using the finite element method (FEM). The dynamic effective material parameters in each unit cell of the graded beam were determined by the dispersion relations and energy band structures. Longitudinal wave propagation was investigated using a numerical method and FEM. The results show that the graded beam allows asymmetric acoustic transmission over a wide range of frequencies.

  7. Graded Alternating-Time Temporal Logic

    Science.gov (United States)

    Faella, Marco; Napoli, Margherita; Parente, Mimmo

    Graded modalities enrich the universal and existential quantifiers with the capability to express the concept of at least k or all but k, for a non-negative integer k. Recently, temporal logics such as μ-calculus and Computational Tree Logic, Ctl, augmented with graded modalities have received attention from the scientific community, both from a theoretical side and from an applicative perspective. Both μ-calculus and Ctl naturally apply as specification languages for closed systems: in this paper, we add graded modalities to the Alternating-time Temporal Logic (Atl) introduced by Alur et al., to study how these modalities may affect specification languages for open systems.

  8. AGC 2 Irradiation Creep Strain Data Analysis

    International Nuclear Information System (INIS)

    Windes, William E.; Rohrbaugh, David T.; Swank, W. David

    2016-01-01

    The Advanced Reactor Technologies Graphite Research and Development Program is conducting an extensive graphite irradiation experiment to provide data for licensing of a high temperature reactor (HTR) design. In past applications, graphite has been used effectively as a structural and moderator material in both research and commercial high temperature gas cooled reactor designs. Nuclear graphite H-451, used previously in the United States for nuclear reactor graphite components, is no longer available. New nuclear graphite grades have been developed and are considered suitable candidates for new HTR reactor designs. To support the design and licensing of HTR core components within a commercial reactor, a complete properties database must be developed for these current grades of graphite. Quantitative data on in service material performance are required for the physical, mechanical, and thermal properties of each graphite grade, with a specific emphasis on data accounting for the life limiting effects of irradiation creep on key physical properties of the HTR candidate graphite grades. Further details on the research and development activities and associated rationale required to qualify nuclear grade graphite for use within the HTR are documented in the graphite technology research and development plan.

  9. AGC 2 Irradiation Creep Strain Data Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Windes, William E. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rohrbaugh, David T. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Swank, W. David [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-08-01

    The Advanced Reactor Technologies Graphite Research and Development Program is conducting an extensive graphite irradiation experiment to provide data for licensing of a high temperature reactor (HTR) design. In past applications, graphite has been used effectively as a structural and moderator material in both research and commercial high temperature gas cooled reactor designs. Nuclear graphite H-451, used previously in the United States for nuclear reactor graphite components, is no longer available. New nuclear graphite grades have been developed and are considered suitable candidates for new HTR reactor designs. To support the design and licensing of HTR core components within a commercial reactor, a complete properties database must be developed for these current grades of graphite. Quantitative data on in service material performance are required for the physical, mechanical, and thermal properties of each graphite grade, with a specific emphasis on data accounting for the life limiting effects of irradiation creep on key physical properties of the HTR candidate graphite grades. Further details on the research and development activities and associated rationale required to qualify nuclear grade graphite for use within the HTR are documented in the graphite technology research and development plan.

  10. AGC 2 Irradiated Material Properties Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Rohrbaugh, David Thomas [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-05-01

    The Advanced Reactor Technologies Graphite Research and Development Program is conducting an extensive graphite irradiation experiment to provide data for licensing of a high temperature reactor (HTR) design. In past applications, graphite has been used effectively as a structural and moderator material in both research and commercial high temperature gas cooled reactor designs. , Nuclear graphite H 451, used previously in the United States for nuclear reactor graphite components, is no longer available. New nuclear graphite grades have been developed and are considered suitable candidates for new HTR reactor designs. To support the design and licensing of HTR core components within a commercial reactor, a complete properties database must be developed for these current grades of graphite. Quantitative data on in service material performance are required for the physical, mechanical, and thermal properties of each graphite grade, with a specific emphasis on data accounting for the life limiting effects of irradiation creep on key physical properties of the HTR candidate graphite grades. Further details on the research and development activities and associated rationale required to qualify nuclear grade graphite for use within the HTR are documented in the graphite technology research and development plan.

  11. Nuclear wastes

    International Nuclear Information System (INIS)

    2002-01-01

    This scientific document presents an introduction to the nuclear wastes problems, the separation process and the transmutation, the political and technical aspects of the storage, the radioprotection standards and the biological effects. (A.L.B.)

  12. Nuclear Disarmament.

    Science.gov (United States)

    Johnson, Christopher

    1982-01-01

    Material about nuclear disarmament and the arms race should be included in secondary school curricula. Teachers can present this technical, controversial, and frightening material in a balanced and comprehensible way. Resources for instructional materials are listed. (PP)

  13. Nuclear analysis

    International Nuclear Information System (INIS)

    1988-01-01

    Basic studies in nuclear analytical techniques include the examination of underlying assumptions and the development and extention of techniques involving the use of ion beams for elemental and mass analysis. 1 ref., 1 tab

  14. Nuclear reaction

    CERN Multimedia

    Penwarden, C

    2001-01-01

    At the European Research Organization for Nuclear Research, Nobel laureates delve into the mysteries of particle physics. But when they invited artists from across the continent to visit their site in Geneva, they wanted a new kind of experiment.

  15. [Nuclear theory

    International Nuclear Information System (INIS)

    1989-06-01

    This report discusses concepts in nuclear theory such as: neutrino nucleosynthesis; double beta decay; neutrino oscillations; chiral symmetry breaking; T invariance; quark propagator; cold fusion; and other related topics

  16. Nuclear constants

    International Nuclear Information System (INIS)

    Foos, J.

    1999-01-01

    This paper is written in two tables. The first one describes the different particles (bosons and fermions). The second one gives the isotopes nuclear constants of the different elements, for Z = 1 to 56. (A.L.B.)

  17. Nuclear constants

    International Nuclear Information System (INIS)

    Foos, J.

    2000-01-01

    This paper is written in two tables. The first one describes the different particles (bosons and fermions). The second one gives the isotopes nuclear constants of the different elements, for Z = 56 to 68. (A.L.B.)

  18. Nuclear constants

    International Nuclear Information System (INIS)

    Foos, J.

    1998-01-01

    This paper is made of two tables. The first table describes the different particles (bosons and fermions) while the second one gives the nuclear constants of isotopes from the different elements with Z = 1 to 25. (J.S.)

  19. Nuclear constants

    International Nuclear Information System (INIS)

    Foos, J.

    1999-01-01

    This paper is written in two tables. The first one describes the different particles (bosons and fermions). The second one gives the isotopes nuclear constants of the different elements, for Z = 56 to 68. (A.L.B.)

  20. Nuclear transmutations

    International Nuclear Information System (INIS)

    Mikulaj, V.

    1992-01-01

    Two types of nuclear transmutations are outlined, namely the radioactive transmutations and nuclear reactions. The basic characteristics are given of radioactive transmutations (gamma transmutations and isomeric transitions, beta, alpha transmutations, spontaneous fission and spontaneous emission of nucleons), their kinetics and the influence of the physical and chemical state of the radionuclide on the transmutation rate. The basic characteristics are described of nuclear reactions (reactions of neutrons including fission, reactions induced by charged particles and photons), their kinetics, effective cross sections and their mechanism. Chemical reactions caused by nuclear transmutations are discussed (recoil energy, properties of hot atoms, Szilard-Chalmers effect). A brief information is given on the behavior of radionuclides in trace concentrations. (Z.S.) 2 tabs., 19 figs., 12 refs

  1. Nuclear waste

    International Nuclear Information System (INIS)

    1992-05-01

    The Nuclear Waste Policy Act of 1982, as amended in 1987, directed the Secretary of Energy to, among other things, investigate Yucca Mountain, Nevada, as a potential site for permanently disposing of highly radioactive wastes in an underground repository. In April 1991, the authors testified on Yucca Mountain project expenditures before your Subcommittee. Because of the significance of the authors findings regrading DOE's program management and expenditures, you asked the authors to continue reviewing program expenditures in depth. As agreed with your office, the authors reviewed the expenditures of project funds made available to the Department of Energy's (DOE) Lawrence Livermore National Laboratory, which is the lead project contractor for developing a nuclear waste package that wold be used for disposing of nuclear waste at Yucca Mountain. This report discusses the laboratory's use of nuclear waste funds to support independent research projects and to manage Yucca Mountain project activities. It also discusses the laboratory's project contracting practices

  2. Nuclear shields

    International Nuclear Information System (INIS)

    Linares, R.C.; Nienart, L.F.; Toelcke, G.A.

    1976-01-01

    A process is described for preparing melt-processable nuclear shielding compositions from chloro-fluoro substituted ethylene polymers, particularly PCTFE and E-CTFE, containing 1 to 75 percent by weight of a gadolinium compound. 13 claims, no drawings

  3. Nuclear option

    International Nuclear Information System (INIS)

    Olson, P.S.

    1983-01-01

    The energy demand complexion of this country is always changing and promises to change in the future. The nuclear industry is responding to changing energy demands through standards writing activities. Since the oil embargo of 1973, there has been a change in the mix of fuels contributing to energy growth in this country; virtually all of the energy growth has come from coal and nuclear power. The predicted expansion of coal use by 1985, over 1977 level, is 37%, while the use of oil is expected to decline by 17%. Use of nuclear power is expected to increase 62% from the 1977 level. The feasibility of using nuclear energy to meet the needs of the USA for electric power is discussed

  4. Nuclear safety

    International Nuclear Information System (INIS)

    Tarride, Bruno

    2015-10-01

    The author proposes an overview of methods and concepts used in the nuclear industry, at the design level as well as at the exploitation level, to ensure an acceptable safety level, notably in the case of nuclear reactors. He first addresses the general objectives of nuclear safety and the notion of acceptable risk: definition and organisation of nuclear safety (relationships between safety authorities and operators), notion of acceptable risk, deterministic safety approach and main safety principles (safety functions and confinement barriers, concept of defence in depth). Then, the author addresses the safety approach at the design level: studies of operational situations, studies of internal and external aggressions, safety report, design principles for important-for-safety systems (failure criterion, redundancy, failure prevention, safety classification). The next part addresses safety during exploitation and general exploitation rules: definition of the operation domain and of its limits, periodic controls and tests, management in case of incidents, accidents or aggressions

  5. Nuclear fission

    International Nuclear Information System (INIS)

    Kodama, T.

    1981-01-01

    The nuclear fission process is pedagogically reviewed from a macroscopic-microscopic point of view. The Droplet model is considered. The fission dynamics is discussed utilizing path integrals and semiclassical methods. (L.C.) [pt

  6. Nuclear physics

    International Nuclear Information System (INIS)

    Connell, K.A.; Warner, D.D.

    1990-01-01

    The first volume of the Annual Report for 1989/90 gives an overview of the Nuclear Structure Facility at Daresbury, its development and a selection of highlights of the year's programme. This volume is complementary, presenting brief specialist reports, submitted by the users, describing the progress and results of each individual proposal. The contents reflect the extremely successful year due in good measure to the performance of the tandem accelerator which provided a record number of hours with ''beam on target''. Reports are grouped in four sections: research into nuclear structure with contributions ordered in increasing Z numbers of the nuclei studied; investigations of nuclear reaction mechanisms; nuclear theory; accelerator operations and development plus experimental instrumentation and techniques. The appendix forms a concise summary of the work at the facility for the year. (author)

  7. Nuclear waste

    International Nuclear Information System (INIS)

    Pligt, J. van der

    1989-01-01

    This chapter present a brief overview of the current situation of siting radioactive wastes. This is followed by an overview of various psychological approaches attempting to analyse public reactions to nuclear facilities. It will be argued that public reactions to nuclear waste factilities must be seen in the context of more general attitudes toward nuclear energy. The latter are not only based upon perceptions of the health and environmental risks but are built on values, and sets of attributes which need not be similar to the representations o the experts and policy-makers. The issue of siting nuclear waste facilities is also embedded in a wider moral and political domain. This is illustrated by the importance of equity issues in siting radioactive wastes. In the last section, the implications of the present line of argument for risk communication and public participation in decisions about siting radioactive wastes will be briefly discussed. (author). 49 refs

  8. Economics and the question of low-grade heat

    International Nuclear Information System (INIS)

    Gorbet, F.W.

    1976-01-01

    This paper examines, from the viewpoint of an economist, the issues involved in the increased waste heat production generated by the rapid acceleration of electrical production and nuclear generation. It reviews some of the literature on low-grade heat - its economic considerations and ecological impact - and examines the applicability of the traditional type of analytical decision tool (cost/benefit analysis) to the efficient design of heat rejection systems. It is recognized that decisions should be made on the basis of social costs and benefits as well as purely monetary considerations. The validity and shortcomings of cost/benefit analysis are presented. It is concluded that, for energy policy planning and waste heat management, economic feasibility studies should lay out the options together with the costs and risks. (author)

  9. Weapons grade plutonium disposition in PWR, CANDU and FR

    International Nuclear Information System (INIS)

    Deplech, M.; Tommasi, J.; Zaetta, A.

    2000-01-01

    In the frame work of the AIDA/MOX phase I/I/ program (1994-1997) between France and Russia, the disposition of plutonium in reactors was studied. The LWR (Light Water Reactor), FR (Fast reactors), CANDU (Heavy Water Reactors), HTR (High Temperature Reactors) options for using excess dismantled weapons plutonium for peaceful commercial nuclear power generating purposes offer some advantages over the remaining options (storage). The AIDA/MOX phase 1 program covers different topics, among which are the neutronic aspects of loading reactors with weapons-grade plutonium. The conclusions are that the weapon plutonium consumption is similar in the different type of reactors. However, the use of inert matrices allows to increase the mass balance for a same denaturing level. The use of Thorium as a matrix or special isotopes to increase the proliferation resistance prove to be insufficient. (author)

  10. The export of weapons grade plutonium to the USA

    International Nuclear Information System (INIS)

    Kollerstrom, N.

    1986-01-01

    Reprocessed spent Magnox fuel from British nuclear power plants has led, it is claimed, to the production of plutonium, some of weapons grade. Some of this has been exported to the USA where, it is assumed, it is used for military purposes. The route and agreements which make this possible and the quantities involved are reported. Inspection by IAEA is insufficient to check the Central Electricity Generating Board's (CEGB) claim that no CEGB plutonium has been used for a military purpose. The CEGB case, presented at the Sizewell Inquiry is discussed. In the United States it is not clear whether plutonium from Britain, at present in a civil stockpile, will be transferred to military use or not. (U.K.)

  11. Adenoid cystic carcinoma of the breast, high grade with basal phenotype, literature review

    Directory of Open Access Journals (Sweden)

    Enaam Junainah

    Full Text Available Adenoid cystic carcinoma (ACC is a rare type of breast carcinoma resembling adenoid cystic carcinoma of other sites. this type of tumors usually characterized by the exhibiting dual cell population of luminal and basaloid with specific growth pattern Most of these sub types are triple-negative with basal-like breast features (tumors that are devoid of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 expression, and express basal cell markers, they are usually low-grade but can be high grade, clinical behavior is indolent despite the nuclear grade, lymph node involvement or distant metastases which is rarely occur. Treatment is either simple mastectomy or lumpectomy. Chemotherapy, radiation and hormonal treatment have limited used in those cases. Keywords: Adenoid cystic carcinoma, Breast, Triple-negative and basal-like phenotype

  12. Children's (Pediatric) Nuclear Medicine

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Children's (Pediatric) Nuclear Medicine Children’s (pediatric) nuclear medicine imaging uses ... limitations of Children's Nuclear Medicine? What is Children's (Pediatric) Nuclear Medicine? Nuclear medicine is a branch of ...

  13. Children's (Pediatric) Nuclear Medicine

    Medline Plus

    Full Text Available ... Professions Site Index A-Z Children's (Pediatric) Nuclear Medicine Children’s (pediatric) nuclear medicine imaging uses small amounts ... Children's Nuclear Medicine? What is Children's (Pediatric) Nuclear Medicine? Nuclear medicine is a branch of medical imaging ...

  14. General Nuclear Medicine

    Science.gov (United States)

    ... Resources Professions Site Index A-Z General Nuclear Medicine Nuclear medicine imaging uses small amounts of radioactive ... of General Nuclear Medicine? What is General Nuclear Medicine? Nuclear medicine is a branch of medical imaging ...

  15. Children's (Pediatric) Nuclear Medicine

    Science.gov (United States)

    ... Professions Site Index A-Z Children's (Pediatric) Nuclear Medicine Children’s (pediatric) nuclear medicine imaging uses small amounts ... Children's Nuclear Medicine? What is Children's (Pediatric) Nuclear Medicine? Nuclear medicine is a branch of medical imaging ...

  16. Children's (Pediatric) Nuclear Medicine

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Children's (Pediatric) Nuclear Medicine Children’s (pediatric) nuclear medicine imaging ... the limitations of Children's Nuclear Medicine? What is Children's (Pediatric) Nuclear Medicine? Nuclear medicine is a branch ...

  17. Children's (Pediatric) Nuclear Medicine

    Medline Plus

    Full Text Available ... Resources Professions Site Index A-Z Children's (Pediatric) Nuclear Medicine Children’s (pediatric) nuclear medicine imaging uses small ... of Children's Nuclear Medicine? What is Children's (Pediatric) Nuclear Medicine? Nuclear medicine is a branch of medical ...

  18. Nuclear instrumentation

    International Nuclear Information System (INIS)

    Weill, Jacky; Fabre, Rene.

    1981-01-01

    This article sums up the Research and Development effort at present being carried out in the five following fields of applications: Health physics and Radioprospection, Control of nuclear reactors, Plant control (preparation and reprocessing of the fuel, testing of nuclear substances, etc.), Research laboratory instrumentation, Detectors. It also sets the place of French industrial activities by means of an estimate of the French market, production and flow of trading with other countries [fr

  19. Nuclear hadrodynamics

    International Nuclear Information System (INIS)

    Geesaman, D.F.

    1984-01-01

    The role of hadron dynamics in the nucleus is illustrated to show the importance of nuclear medium effects in hadron interactions. The low lying hadron spectrum is considered to provide the natural collective variables for nuclear systems. Recent studies of nucleon-nucleon and delta-nucleon interactions are reviewed, with emphasis on the type of experimental phenomena which signal the importance of the many-body dynamics. 28 references

  20. Seguro Nuclear

    International Nuclear Information System (INIS)

    Oliveira, S.C.C. de.

    1978-04-01

    A description of the constitutive elements of insurance and its features in the field of law, and special legislation about the matter are given. The relationship between the liability of the nuclear power plant operator and the international conventions about civil liability on nuclear damage is discussed. Some considerations on damage reparing in the United States, Germany, France and Spain are presented. (A.L.S.L.) [pt

  1. Nuclear medicine

    International Nuclear Information System (INIS)

    Sibille, L.; Nalda, E.; Collombier, L.; Kotzki, P.O.; Boudousq, V.

    2011-01-01

    Nuclear medicine is a medical specialty using the properties of radioactivity. Radioactive markers associated with vectors are used as a tracer or radiopharmaceutical for diagnostic purposes and/or therapy. Since its birth more than half a century ago, it has become essential in the care of many patients, particularly in oncology. After some definitions, this paper presents the main nuclear techniques - imaging for diagnostic, radiopharmaceuticals as therapeutic agents, intra-operative detection, technique of radioimmunoassay - and the future of this field. (authors)

  2. Nuclear waste

    International Nuclear Information System (INIS)

    1988-01-01

    The Department of Energy has proposed a draft plan for investigating the Yucca Mountain, Nevada, site to determine if it suitable for a waste repository. This fact sheet provides information on the status of DOE's and the Nuclear Regulatory Commission's efforts to streamline what NRC expects will be the largest and most complex nuclear-licensing proceeding in history, including the development of an electronic information management system called the Licensing Support System

  3. Nuclear safety

    International Nuclear Information System (INIS)

    Arnott, D.

    1981-01-01

    Dr Arnott, scientific consultant to PANDORA, emphasises our lack of knowledge of the behaviour of highly active radioactive wastes, particularly effluents, and their characteristics. He proposes that they should be stored, preferably in a solidified state, until our knowledge allows their safe disposal. Political aspects and government policies are discussed and human fallibility is stressed. The nuclear establishment and nuclear power programme are severely criticised. (U.K.)

  4. Nuclear astrophysics

    International Nuclear Information System (INIS)

    Lehoucq, Roland; Klotz, Gregory

    2015-11-01

    Astronomy deals with the position and observation of the objects in our Universe, from planets to galaxies. It is the oldest of the sciences. Astrophysics is the study of the physical properties of these objects. It dates from the start of the 20. century. Nuclear astrophysics is the marriage of nuclear physics, a laboratory science concerned with the infinitely small, and astrophysics, the science of what is far away and infinitely large. Its aim is to explain the origin, evolution and abundance of the elements in the Universe. It was born in 1938 with the work of Hans Bethe, an American physicist who won the Nobel Prize for physics in 1967, on the nuclear reactions that can occur at the center of stars. It explains where the incredible energy of the stars and the Sun comes from and enables us to understand how they are born, live and die. The matter all around us and from which we are made, is made up of ninety-two chemical elements that can be found in every corner of the Universe. Nuclear astrophysics explains the origin of these chemical elements by nucleosynthesis, which is the synthesis of atomic nuclei in different astrophysical environments such as stars. Nuclear astrophysics provides answers to fundamental questions: - Our Sun and the stars in general shine because nuclear reactions are taking place within them. - The stars follow a sequence of nuclear reaction cycles. Nucleosynthesis in the stars enables us to explain the origin and abundance of elements essential to life, such as carbon, oxygen, nitrogen and iron. - Star explosions, in the form of supernovae, disperse the nuclei formed by nucleosynthesis into space and explain the formation of the heaviest chemical elements such as gold, platinum and lead. Nuclear astrophysics is still a growing area of science. (authors)

  5. Nuclear physics

    International Nuclear Information System (INIS)

    Spicer, B.M.

    1981-01-01

    Major centres of experimental nuclear physics are at Melbourne University, A.N.U., the A.A.E.C., James Cook University and the University of Western Australia. Groups working in theoretical nuclear physics exist at Melbourne, A.N.U., the A.A.E.C., Flinders and Adelaide Universities and the University of Western Australia. The activities of these groups are summarised

  6. Nuclear energy

    International Nuclear Information System (INIS)

    1996-01-01

    Several issues concerning nuclear energy in France during 1996 are presented: permission of a demand for installing underground laboratories in three sites (Marcoule, Bure and Chapelle-Baton); a report assessing the capacity of Superphenix plant to operate as a research tool; the project of merging between Framatome and Gec-Alsthom companies; the revision of a general report on nuclear energy in France; the issue of military plutonium management

  7. Nuclear Data

    Energy Technology Data Exchange (ETDEWEB)

    White, Morgan C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-01-23

    PowerPoint presentation targeted for educational use. Nuclear data comes from a variety of sources and in many flavors. Understanding where the data you use comes from and what flavor it is can be essential to understand and interpret your results. This talk will discuss the nuclear data pipeline with particular emphasis on providing links to additional resources that can be used to explore the issues you will encounter.

  8. Nuclear medicine

    International Nuclear Information System (INIS)

    Blanquet, Paul; Blanc, Daniel.

    1976-01-01

    The applications of radioisotopes in medical diagnostics are briefly reviewed. Each organ system is considered and the Nuclear medicine procedures pertinent to that system are discussed. This includes, the principle of the test, the detector and the radiopharmaceutical used, the procedure followed and the clinical results obtained. The various types of radiation detectors presently employed in Nuclear Medicine are surveyed, including scanners, gamma cameras, positron cameras and procedures for obtaining tomographic presentation of radionuclide distributions [fr

  9. Nuclear medicine

    International Nuclear Information System (INIS)

    Chamberlain, M.J.

    1986-01-01

    Despite an aggressive, competitive diagnostic radiology department, the University Hospital, London, Ontario has seen a decline of 11% total (in vivo and in the laboratory) in the nuclear medicine workload between 1982 and 1985. The decline of in vivo work alone was 24%. This trend has already been noted in the U.S.. Nuclear medicine is no longer 'a large volume prosperous specialty of wide diagnostic application'

  10. Nuclear cardiac

    International Nuclear Information System (INIS)

    Slutsky, R.; Ashburn, W.L.

    1982-01-01

    The relationship between nuclear medicine and cardiology has continued to produce a surfeit of interesting, illuminating, and important reports involving the analysis of cardiac function, perfusion, and metabolism. To simplify the presentation, this review is broken down into three major subheadings: analysis of myocardial perfusion; imaging of the recent myocardial infarction; and the evaluation of myocardial function. There appears to be an increasingly important relationship between cardiology, particularly cardiac physiology, and nuclear imaging techniques

  11. Nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, S M [Bhabha Atomic Research Centre, Bombay (India). Radiation Medicine Centre

    1967-01-01

    The article deals with the growth of nuclear medicine in India. Radiopharmaceuticals both in elemental form and radiolabelled compounds became commercially available in India in 1961. Objectives and educational efforts of the Radiation Medicine Centre setup in Bombay are mentioned. In vivo tests of nuclear medicine such as imaging procedures, dynamic studies, dilution studies, thyroid function studies, renal function studies, linear function studies, blood flow, and absorption studies are reported. Techniques of radioimmunoassay are also mentioned.

  12. Nuclear technology

    International Nuclear Information System (INIS)

    1983-03-01

    This report examines nuclear technology in Canada, with emphasis on Quebec, as a means of revitilizing industry. The historical, present day, and future states of Atomic Energy of Canada Limited are examined. Future research programs are discussed in greatest detail. These range from disposal of porcine wastes to new applications for electricity to nuclear medical techniques (to cite only a few examples). The executive summary is written in English. (23 fig., 16 tab.)

  13. Nuclear risk

    International Nuclear Information System (INIS)

    Mulkers, G.

    1988-01-01

    This file includes data on risks insured by the nuclear insurance pool in Belgium and on the Chernobyl accident covering injury, economic damage and compensation for the latter. Also included are the texts of the IAEA Conventions on Early Notification and on Assistance in Case of a Nuclear Accident as well as that of a Convention on long-distance transfrontier atmospheric pollution signed in Geneva [fr

  14. Nuclear accidents

    International Nuclear Information System (INIS)

    1987-01-01

    On 27 May 1986 the Norwegian government appointed an inter-ministerial committee of senior officials to prepare a report on experiences in connection with the Chernobyl accident. The present second part of the committee's report describes proposals for measures to prevent and deal with similar accidents in the future. The committee's evaluations and proposals are grouped into four main sections: Safety and risk at nuclear power plants; the Norwegian contingency organization for dealing with nuclear accidents; compensation issues; and international cooperation

  15. Nuclear education

    International Nuclear Information System (INIS)

    Kemeny, L.G.

    1987-01-01

    All scientists and technologists are agreed that the coal based fuel cycle is somewhere between 50 to 300 times more dangerous than the uranium fuel cycle. Under these circumstances it is not difficult to show that on a more quantitative basis, the nuclear industry, in all countries, has an unblemished safety record when compared with other energy sources. Various hazards and benefits of nuclear power are analyzed in this paper comparing with other energy sources. (Liu)

  16. Nuclear astrophysics

    International Nuclear Information System (INIS)

    Arnould, M.; Takahashi, K.

    1999-01-01

    Nuclear astrophysics is that branch of astrophysics which helps understanding of the Universe, or at least some of its many faces, through the knowledge of the microcosm of the atomic nucleus. It attempts to find as many nuclear physics imprints as possible in the macrocosm, and to decipher what those messages are telling us about the varied constituent objects in the Universe at present and in the past. In the last decades much advance has been made in nuclear astrophysics thanks to the sometimes spectacular progress made in the modelling of the structure and evolution of the stars, in the quality and diversity of the astronomical observations, as well as in the experimental and theoretical understanding of the atomic nucleus and of its spontaneous or induced transformations. Developments in other subfields of physics and chemistry have also contributed to that advance. Notwithstanding the accomplishment, many long-standing problems remain to be solved, and the theoretical understanding of a large variety of observational facts needs to be put on safer grounds. In addition, new questions are continuously emerging, and new facts endangering old ideas. This review shows that astrophysics has been, and still is, highly demanding to nuclear physics in both its experimental and theoretical components. On top of the fact that large varieties of nuclei have to be dealt with, these nuclei are immersed in highly unusual environments which may have a significant impact on their static properties, the diversity of their transmutation modes, and on the probabilities of these modes. In order to have a chance of solving some of the problems nuclear astrophysics is facing, the astrophysicists and nuclear physicists are obviously bound to put their competence in common, and have sometimes to benefit from the help of other fields of physics, like particle physics, plasma physics or solid-state physics. Given the highly varied and complex aspects, we pick here some specific nuclear

  17. Development of Safety Grade PLC (POSAFE-Q) and Performance Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang Hwoi; Park, Won Man; Choi, Jong Gyun; Lee, Dong Young [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); No, Young Hun; Song, Seung Hwan [POSCON, Seoul (Korea, Republic of)

    2006-07-01

    The safety grade PLC (POSAFE-Q) is being developed in the Korea Nuclear Instrumentation and Control System (KNICS) R and D project. The PLC satisfies Safety Class 1E, Quality Class 1, and Seismic Category I. The software such as the RTOS and firmware are being developed according to the safety critical software life cycle. Especially, the formal method is applied to design the SRS (Software Requirement Spec.) and the SDS (Software Design Specification.) to be error-free. The POSAFE-Q has several modules such as processor module, input and output modules, communication modules, redundant processor module, redundant power modules, etc,. To verify the function and performance, several tests such as CT, IT and ST were performed. And also, the equipment qualification test for environment, EMI and EMC, and seismic ware performed. All tests are satisfied with the requirements and specification for safety grade PLC, and the criteria for safety system in nuclear power plants.

  18. Development of Safety Grade PLC (POSAFE-Q) and Performance Test Results

    International Nuclear Information System (INIS)

    Kim, Chang Hwoi; Park, Won Man; Choi, Jong Gyun; Lee, Dong Young; No, Young Hun; Song, Seung Hwan

    2006-01-01

    The safety grade PLC (POSAFE-Q) is being developed in the Korea Nuclear Instrumentation and Control System (KNICS) R and D project. The PLC satisfies Safety Class 1E, Quality Class 1, and Seismic Category I. The software such as the RTOS and firmware are being developed according to the safety critical software life cycle. Especially, the formal method is applied to design the SRS (Software Requirement Spec.) and the SDS (Software Design Specification.) to be error-free. The POSAFE-Q has several modules such as processor module, input and output modules, communication modules, redundant processor module, redundant power modules, etc,. To verify the function and performance, several tests such as CT, IT and ST were performed. And also, the equipment qualification test for environment, EMI and EMC, and seismic ware performed. All tests are satisfied with the requirements and specification for safety grade PLC, and the criteria for safety system in nuclear power plants

  19. Nuclear safety

    International Nuclear Information System (INIS)

    2014-01-01

    The Program on Nuclear Safety comprehends Radioprotection, Radioactive Waste Management and Nuclear Material Control. These activities are developed at the Nuclear Safety Directory. The Radioactive Waste Management Department (GRR) was formally created in 1983, to promote research and development, teaching and service activities in the field of radioactive waste. Its mission is to develop and employ technologies to manage safely the radioactive wastes generated at IPEN and at its customer’s facilities all over the country, in order to protect the health and the environment of today's and future generations. The Radioprotection Service (GRP) aims primarily to establish requirements for the protection of people, as workers, contractors, students, members of the general public and the environment from harmful effects of ionizing radiation. Furthermore, it also aims to establish the primary criteria for the safety of radiation sources at IPEN and planning and preparing for response to nuclear and radiological emergencies. The procedures about the management and the control of exposures to ionizing radiation are in compliance with national standards and international recommendations. Research related to the main activities is also performed. The Nuclear Material Control has been performed by the Safeguard Service team, which manages the accountability and the control of nuclear material at IPEN facilities and provides information related to these activities to ABACC and IAEA. (author)

  20. Nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, H [Power Reactor and Nuclear Fuel Development Corp., Tokyo (Japan)

    1976-10-01

    It is expected that nuclear power generation will reach 49 million kW in 1985 and 129 million kW in 1995, and the nuclear fuel having to be supplied and processed will increase in proportion to these values. The technical problems concerning nuclear fuel are presented on the basis of the balance between the benefit for human beings and the burden on the human beings. Recently, especially the downstream of nuclear fuel attracts public attention. Enriched uranium as the raw material for light water reactor fuel is almost monopolized by the U.S., and the technical information has not been published for fear of the diversion to nuclear weapons. In this paper, the present situations of uranium enrichment, fuel fabrication, transportation, reprocessing and waste disposal and the future problems are described according to the path of nuclear fuel cycle. The demand and supply of enriched uranium in Japan will be balanced up to about 1988, but afterwards, the supply must rely upon the early establishment of the domestic technology by centrifugal separation method. No problem remains in the fabrication of light water reactor fuel, but for the fabrication of mixed oxide fuel, the mechanization of the production facility and labor saving are necessary. The solution of the capital risk for the construction of the second reprocessing plant is the main problem. Japan must develop waste disposal techniques with all-out efforts.