Nuclear weapons and nuclear energy - A study in global governance

International Nuclear Information System (INIS)

Imai, R.

1999-01-01

The projects of the two superpowers concerning the nuclear armament and intercontinental ballistic missiles, the policy of the two governments in monopoly of these armaments and prohibiting other countries from owning them, treaties signed by the governments, and the role of the United Nations and the International Atomic Energy Agency were presented

Superpower Crises in a Less Confrontational World: Results of an Experimental Simulation

Science.gov (United States)

1990-04-01

interteam communications via RAND’s electronic mail system for gaming purposes. 2 The "pilot runs" were designated Games Three and Four, and are referred... game , the impact of a changing real-world international context-a more benign image of the adversary and a less competitive superpower relationship...information overload they faced. Several believed that these problems were game artifacts (which they attributed to our use of the electronic mail system

India's nuclear spin-off

International Nuclear Information System (INIS)

Kaul, Ravi.

1974-01-01

After examining world-wide reactions of the foreign governments and news media to the India's peaceful nuclear experiment (PNE) in the Rajasthan Desert on 18 May 1974, development of nuclear technology in India is assessed and its economic advantages are described. Implications of the Non-Proliferation Treaty are explained. Psychological impact of India's PNE on India's neighbours and superpowers and associated political problems in context of proliferation of nuclear weapons are discussed in detail. (M.G.B.)

High temperature heat exchange: nuclear process heat applications

International Nuclear Information System (INIS)

Vrable, D.L.

1980-09-01

The unique element of the HTGR system is the high-temperature operation and the need for heat exchanger equipment to transfer nuclear heat from the reactor to the process application. This paper discusses the potential applications of the HTGR in both synthetic fuel production and nuclear steel making and presents the design considerations for the high-temperature heat exchanger equipment

2 SDI, alliance coherence, and East-West nuclear stability

International Nuclear Information System (INIS)

Kolodzie, E.A.

1988-01-01

The nuclear modernization programme, offensive and defensive, now being implemented or seriously proposed by the Western nuclear states and the Soviet Union pose critical problems for the stability of the European and global nuclear balance. The Reagan administration's Strategic Defence Initiative (SDI) and the dramatic growth of British and French nuclear capabilities add new strains on the arms race now underway between the superpowers. Current and emerging instabilities must be addressed promptly along a broad political front, within and outside the framework of the Atlantic Alliance, before they further split the alliance and damage efforts---principally those being pursued at Geneva in the superpower arms control talks---to manage the nuclear balance and the conflicts that divide the two blocs in Europe and elsewhere. The first part of this paper diagnoses the disturbing elements of the evolving nuclear environment which promotes instability. The second suggests an approach -- complex bilateralism -- that might be employed to bring these destabilizing trends under control to promote the development of more coherent, cohesive, and mutually confident alliance strategic policies than exist today and to enhance East-West stability

Materials for nuclear diffusion-bonded compact heat exchangers

International Nuclear Information System (INIS)

Li, Xiuqing; Smith, Tim; Kininmont, David; Dewson, Stephen John

2009-01-01

This paper discusses the characteristics of materials used in the manufacture of diffusion bonded compact heat exchangers. Heatric have successfully developed a wide range of alloys tailored to meet process and customer requirements. This paper will focus on two materials of interest to the nuclear industry: dual certified SS316/316L stainless steel and nickel-based alloy Inconel 617. Dual certified SS316/316L is the alloy used most widely in the manufacture of Heatric's compact heat exchangers. Its excellent mechanical and corrosion resistance properties make it a good choice for use with many heat transfer media, including water, carbon dioxide, liquid sodium, and helium. As part of Heatric's continuing product development programme, work has been done to investigate strengthening mechanisms of the alloy; this paper will focus in particular on the effects of nitrogen addition. Another area of Heatric's programme is Alloy 617. This alloy has recently been developed for diffusion bonded compact heat exchanger for high temperature nuclear applications, such as the intermediate heat exchanger (IHX) for the very high temperature nuclear reactors for production of electricity, hydrogen and process heat. This paper will focus on the effects of diffusion bonding process and cooling rate on the properties of alloy 617. This paper also compares the properties and discusses the applications of these two alloys to compact heat exchangers for various nuclear processes. (author)

China’s Foreign Policy Toward North Korea: The Nuclear Issue

Science.gov (United States)

2012-12-01

black or white, what matters is it catches mice ,” represented China’s strategy. Among Western countries, China understood that rapprochement with...nonproliferation issue. Until 1970, China considered that superpowers used nuclear nonproliferation as a way to monopolize nuclear weapons. Thus, in

Charge-exchange giant resonances as probes of nuclear structure

International Nuclear Information System (INIS)

Blomgren, J.

2001-09-01

Giant resonances populated in charge-exchange reactions can reveal detailed information about nuclear structure properties, in spite of their apparent featurelessness. The (p,n) and (n,p) reactions - as well as their analog reactions - proceed via the same nuclear matrix element as beta decay. Thereby, they are useful for probing electroweak properties in nuclei, especially for those not accessible to beta decay. The nuclear physics aspects of double beta decay might be investigated in double charge-exchange reactions. detailed nuclear structure information, such as the presence of ground-state correlations, can be revealed via identification of 'first-forbidden' transitions. In addition, astrophysics aspects and halo properties of nuclei have been investigated in charge exchange. Finally, these experiments have questioned our knowledge of the absolute strength of the strong interaction

The nuclear spread: a Third World view

International Nuclear Information System (INIS)

Kapur, A.

1980-01-01

The view of the Third World of nuclear power and international relations is contrasted with that of the superpowers. Aspects considered include the Non-Proliferation Treaty, factors for and against proliferation, regional and international environments, vertical versus horizontal proliferation. (U.K.)

A nuclear-weapon-free Middle East

International Nuclear Information System (INIS)

Jortner, Joshua

1986-01-01

The paper examines the issue of nuclear-weapon States involvement in regional conflicts, and whether such a conflict in the Middle East could trigger a nuclear war between the Super-Powers. Comments on the Middle Eastern situation are given, along with a discussion of the Non-Proliferation Treaty (NPT) and the Middle East, Israel and the NPT, and the nuclear potential in Arab countries. The proposal, by Israel, of a nuclear weapon-free zone in the Middle East is outlined. (UK)

Reducing nuclear danger through intergovernmental technical exchanges on nuclear materials safety management

International Nuclear Information System (INIS)

Jardine, L.J.; Peddicord, K.L.; Witmer, F.E.; Krumpe, P.F.; Lazarev, L.; Moshkov, M.

1997-01-01

The United States and Russia are dismantling nuclear weapons and generating hundreds of tons of excess plutonium and high enriched uranium fissile nuclear materials that require disposition. The U.S. Department of Energy and Russian Minatom organizations.are planning and implementing safe, secure storage and disposition operations for these materials in numerous facilities. This provides a new opportunity for technical exchanges between Russian and Western scientists that can establish an improved and sustained common safety culture for handling these materials. An initiative that develops and uses personal relationships and joint projects among Russian and Western participants involved in fissile nuclear materials safety management contributes to improving nuclear materials nonproliferation and to making a safer world. Technical exchanges and workshops are being used to systematically identify opportunities in the nuclear fissile materials facilities to improve and ensure the safety of workers, the public, and the environment

Superpower nuclear minimalism in the post-Cold War era?. Revised

Energy Technology Data Exchange (ETDEWEB)

Graben, E.K.

1992-07-01

With the end of the Cold War and the breakup of the Soviet Union, the strategic environment has fundamentally changed, so it would seem logical to reexamine strategy as well. There are two main schools of nuclear strategic thought: a maximalist school, which emphasizes counterforce superiority and nuclear war-fighting capability, and a MAD-plus school, which emphasizes survivability of an assured destruction capability along with the ability to deliver small, limited nuclear attacks in the event that conflict occurs. The MAD-plus strategy is the more logical of the two strategies, because the maximalist strategy is based on an attempt to conventionalize nuclear weapons which is unrealistic.

The American Nuclear Society's international student exchange program

International Nuclear Information System (INIS)

Bornstein, I.

1988-01-01

The American Nuclear Society's (ANS's) International Student Exchange Program sponsors bilateral exchanges of students form graduate schools in American universities with students from graduate schools in France, the Federal Republic of Germany (FRG), and Japan. The program, now in its 12th year, was initiated in response to an inquiry to Argonne National Laboratory (ANL) from the director of the Centre d'Etudes Nucleaires de Saclay proposing to send French nuclear engineering students to the United States for summer jobs. The laboratory was asked to accept two students to work on some nuclear technology activity and ANS was invited to send American students to France on an exchange basis. To date, 200 students have taken part in the program. It has been a maturing and enriching experience for them, and many strong and enduring friendships have been fostered among the participants, many of whom will become future leaders in their countries

Fuel exchanging machine for a nuclear ship

International Nuclear Information System (INIS)

Hayashi, Tetsuji.

1984-01-01

Purpose: To prevent atmospheric contaminations upon fuel exchange thereby keep the environmental circumstance clean in the periphery of the nuclear ship. Constitution: A nuclear reactor container is disposed to the inside of a containing vessel in the ship body and a shutter is mounted to the upper opening of the ship body. Further, a landing container having a bottom opening equipped with shutter for alingning the upper opening equipped with shuuter of the ship is elevatably suspended to the trolley of a crane by way of a wire rope and a winch, and a fuel exchange cask is elevatably disposed to the inside of the landing container. Further, airs in the inside of the container is adapted to be discharged externally through a filter by means of a blower and the inside is kept at a negative pressure. Thus, since the containing vessel is covered with the landing container upon fuel exchanging operation, atmospheric contamination can be prevented sufficiently. (Sekiya, K.)

Primer on nuclear exchange models

Energy Technology Data Exchange (ETDEWEB)

Hafemeister, David [Physics Department, Cal Poly University, San Luis Obispo, California (United States)

2014-05-09

Basic physics is applied to nuclear force exchange models between two nations. Ultimately, this scenario approach can be used to try and answer the age old question of 'how much is enough?' This work is based on Chapter 2 of Physics of Societal Issues: Calculations on National Security, Environment and Energy (Springer, 2007 and 2014)

The de-escalation of nuclear crises

International Nuclear Information System (INIS)

Nation, J.E.

1992-01-01

Whether and by what means nations can successfully de-escalate nuclear crises - and avoid the disastrous effects of nuclear war - will remain two of the most critical challenges facing humankind. Whatever the future of superpower relations, the United States, the Soviet Union, and other nations will undoubtedly continue to possess and to threaten the use of nuclear weapons. Moreover, the number of nations with nuclear weapons seems likely to increase. This examines how nations in crises might successfully move back from the brink of nuclear war - and how confidence-building measures might help and hinder the de-escalatory process

Progress in scale-up of second-generation high-temperature superconductors at SuperPower Inc

International Nuclear Information System (INIS)

Xie, Y.-Y.; Knoll, A.; Chen, Y.; Li, Y.; Xiong, X.; Qiao, Y.; Hou, P.; Reeves, J.; Salagaj, T.; Lenseth, K.; Civale, L.; Maiorov, B.; Iwasa, Y.; Solovyov, V.; Suenaga, M.; Cheggour, N.; Clickner, C.; Ekin, J.W.; Weber, C.; Selvamanickam, V.

2005-01-01

SuperPower is focused on scaling up second-generation (2-G) high-temperature superconductor (HTS) technology to pilot-scale manufacturing. The emphasis of this program is to develop R and D solutions for scale-up issues in pilot-scale operations to lay the foundation for a framework for large-scale manufacturing. Throughput continues to be increased in all process steps including substrate polishing, buffer and HTS deposition. 2-G HTS conductors have been produced in lengths up to 100 m. Process optimization with valuable information provided by several unique process control and quality-control tools has yielded performances of 6000-7000 A m (77 K, 0 T) in 50-100 m lengths using two HTS fabrication processes: metal organic chemical vapor deposition (MOCVD) and pulsed laser deposition (PLD). Major progress has been made towards the development of practical conductor configurations. Modifications to the HTS fabrication process have resulted in enhanced performance in magnetic fields. Industrial slitting and electroplating processes have been successfully adopted to fabricate tapes in width of 4 mm and with copper stabilizer for cable and coil applications. SuperPower's conductor configuration has yielded excellent mechanical properties and overcurrent carrying capability. Over 60 m of such practical conductors with critical current over 100 A/cm-width have been delivered to Sumitomo Electric Industries, Ltd. for prototype cable construction

Effects on the atmosphere of a major nuclear exchange

International Nuclear Information System (INIS)

1985-01-01

The Committee on the Atmospheric Effects of Nuclear Explosions addressed the following charge: (1) determine the manner in which the atmosphere of the earth would be modified by a major exchange of nuclear weapons and, insofar as the current state of knowledge and understanding permits, give a quantitative description of the more important of the changes; and (2) recommend research and exploratory work appropriate to a better understanding of the question. Recent calculations by different investigators suggest that the climatic effects from a major nuclear exchange could be large in scale. Although there are enormous uncertainties involved in the calculations, the committee believes that long-term climatic effects with severe implications for the biosphere could occur, and these effects should be included in any analysis of the consequences of nuclear war. The estimates are necessarily rough and can only be used as a general indication of the seriousness of what might occur

EXFOR Systems Manual Nuclear reaction Data Exchange Format

International Nuclear Information System (INIS)

McLane, V.

2000-01-01

EXFOR is an exchange format designed to allow transmission of nuclear reaction data between the members of the Nuclear Data Centers Network. This document has been written for use by the members of the Network and includes matters of procedure and protocol, as well as detailed rules for the compilation of data. Users may prefer to consult EXFOR Basics' for a brief description of the format

Ion exchange technology in the nuclear fuel cycle

International Nuclear Information System (INIS)

1986-02-01

The application of ion exchange has been expanded to various parts of the nuclear fuel cycle. Major applications are in uranium production facilities, nuclear power plants, spent fuel reprocessing and waste treatment. Furthermore, application to isotope separation has been under development. The appendix contains a compilation of resin data. A separate abstract was prepared for each of the 6 chapters in this technical document

EXFOR SYSTEMS MANUAL NUCLEAR REACTION DATA EXCHANGE FORMAT.

Energy Technology Data Exchange (ETDEWEB)

MCLANE,V.; NUCLEAR DATA CENTER NETWORK

2000-05-19

EXFOR is an exchange format designed to allow transmission of nuclear reaction data between the members of the Nuclear Data Centers Network. This document has been written for use by the members of the Network and includes matters of procedure and protocol, as well as detailed rules for the compilation of data. Users may prefer to consult EXFOR Basics' for a brief description of the format.

Sigma exchange in the nuclear force and effective field theory

International Nuclear Information System (INIS)

Donoghue, John F.

2006-01-01

In the phenomenological description of the nuclear interaction an important role is traditionally played by the exchange of a scalar I=0 meson, the sigma, of mass 500-600 MeV, which however is not seen clearly in the particle spectrum and which has a very ambiguous status in QCD. I show that a remarkably simple and reasonably controlled combination of ingredients can reproduce the features of this part of the nuclear force. The use of chiral perturbation theory calculations for two pion exchange supplemented by the Omnes function for pion rescattering suffices to reproduce the magnitude and shape of the exchange of a supposed σ particle. I also attempt to relate this description to the contact interaction that enters more modern descriptions of the internucleon interaction

Pion-nucleus double charge exchange and the nuclear shell model

International Nuclear Information System (INIS)

Auerbach, N.; Gibbs, W.R.; Ginocchio, J.N.; Kaufmann, W.B.

1988-01-01

The pion-nucleus double charge exchange reaction is studied with special emphasis on nuclear structure. The reaction mechanism and nuclear structure aspects of the process are separated using both the plane-wave and distorted-wave impulse approximations. Predictions are made employing both the seniority model and a full shell model (with a single active orbit). Transitions to the double analog state and to the ground state of the residual nucleus are computed. The seniority model yields particularly simple relations among double charge exchange cross sections for nuclei within the same shell. Limitations of the seniority model and of the plane-wave impulse approximation are discussed as well as extensions to the generalized seniority scheme. Applications of the foregoing ideas to single charge exchange are also presented

Development of inorganic ion exchangers for nuclear waste remediation. 1997 annual progress report

International Nuclear Information System (INIS)

Clearfield, A.; Collins, J.L.; Egan, B.Z.

1997-01-01

'In this research program, Oak Ridge National Laboratory (ORNL) is collaborating with Texas A and M University in the development of highly selective inorganic ion exchangers for the removal of cesium and strontium from nuclear tank-waste and from groundwater. Inorganic ion exchangers are developed and characterized at Texas A and M University; ORNL is involved in preparing the powders in engineered forms and testing the performance of the sorbents in actual nuclear waste solutions. The Texas A and M studies are divided into two main categories: (1) exchangers for tank wastes and (2) exchangers for groundwater remediation. These are subdivided into exchangers for use in acid and alkaline solutions for tank wastes and those that can be recycled for use in groundwater remediation. The exchangers will also be considered for in situ immobilization of radionuclides. The approach will involve a combination of exchanger synthesis, structural characterization, and ion exchange behavior. ORNL has developed a technique for preparing inorganic ion exchangers in the form of spherules by a gel-sphere internal gelation process. This technology, which was developed and used for making nuclear fuels, has the potential of greatly enhancing the usability of many other special inorganic materials because of the improved flow dynamics of the spherules. Also, pure inorganic spherules can be made without the use of binders. ORNL also has access to actual nuclear waste in the form of waste tank supernatant solutions for testing the capabilities of the sorbents for removing the cesium and strontium radionuclides from actual waste solutions. The ORNL collaboration will involve the preparation of the powdered ion exchangers, developed and synthesized at Texas A and M, in the form of spherules, and evaluating the performance of the exchangers in real nuclear waste solutions. Selected sorbents will be provided by Texas A and M for potential incorporation into microspheres, and the performance

Heat exchanger. [Nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Molina, C; Brisseaux, A

1976-01-19

This invention concerns a heat exchanger between a fluid flowing through a tube and a gas. Such an exchanger can be used, inter alia, for removing calories that cannot be used for generating electricity in a thermal or nuclear power station. This exchanger can withstand any pressure surges in the system and even the use of a high vapour pressure coolant such as ammonia, since the fluid flows in a round tube with low pressure drops (both with respect to the fluid to be cooled and the cooling air). It is rigid enough to stand up to being moved and handled as well as to gusts of wind. It is formed of units that can be handled without difficulty and that are easily dismantable and interchangeable, even in service, and it is easily maintained. The exchange area is high for a minimum frontal area and this enables the size of the supporting frame to be reduced and makes it easy to hide it behind a screen of trees should this prove necessary. Finally, it is composed of a small number of standard units thus reducing the industrial production cost. These units are rectangular plates, each one being a flat tubular coil fitted between two flat parallel sheet metal plates having on their outer sides flat top raised bosses. These units are assembled together by the tops of the bosses so as to form an exchanger bank, each bank comprising two collectors to which the bank coils are tightly connected.

Pion double charge exchange and nuclear structure

International Nuclear Information System (INIS)

Ginocchio, J.N.

1987-01-01

Pion double charge exchange to both the double-analog state and the ground state is studied for medium weight nuclei. The relative cross section of these two transitions and the importance of nuclear structure as a function of pion kinetic energy is examined. 16 figs., 5 tabs

EXFOR systems manual: Nuclear reaction data exchange format

International Nuclear Information System (INIS)

McLane, V.

1996-07-01

This document describes EXFOR, the exchange format designed to allow transmission of nuclear reaction data between the members of the Nuclear Data Centers Network. In addition to storing the data and its bibliographic information, experimental information, including source of uncertainties, is also compiled. The status and history of the data set is also included, e.g., the source of the data, any updates which have been made, and correlations to other data sets. The exchange format, as outlined, is designed to allow a large variety of numerical data tables with explanatory and bibliographic information to be transmitted in an easily machine-readable format (for checking and indicating possible errors) and a format that can be read by personnel (for passing judgment on and correcting any errors indicated by the machine)

Bibliographical survey of heat exchangers for nuclear power plants and problems of HTGR

International Nuclear Information System (INIS)

Yamao, Hiroyuki; Okamoto, Yoshizo; Sanokawa, Konomo

1977-04-01

The problems in development of heat exchangers for nuclear reactors have been examined in literature survey through Annual Index Subjects of NSA (Nuclear Science Abstracts) for the past ten years. R and D on heat exchangers for LMFBR, HTGR, LWR and HWR are on the increase. In the case of HTGRs, R and D on heat resisting materials including the corrosion and on hydrogen permeation of heat exchanger walls in high temperature pressure helium environment are important. Future R and D subjects for HTGR heat exchangers in showing the high temperature endurance are presented. (auth.)

Nuclear arms cleanup

International Nuclear Information System (INIS)

Cooper, M.H.

1994-01-01

The Soviet Union's demise five years ago brought an end to the Cold War, the 45-year arms race between the Soviet superpower and the United States. The euphoria that greeted the end of this bloodless conflict has dampened somewhat, however, as U.S. officials and their counterparts in the former Soviet republics come to grips with its legacy: thousands of highly toxic and politically destabilizing nuclear weapons. With no more perceived need for much of their vast arsenals, the governments have agreed to dismantle large numbers of nuclear warheads. But the agencies involved in this task face a daunting technical and political problem: what to do with the thousands of tons of plutonium and uranium that are the main ingredients of nuclear weapons

Modeling Choices in Nuclear Warfighting: Two Classroom Simulations on Escalation and Retaliation

Science.gov (United States)

Schofield, Julian

2013-01-01

Two classroom simulations--"Superpower Confrontation" and "Multipolar Asian Simulation"--are used to teach and test various aspects of the Borden versus Brodie debate on the Schelling versus Lanchester approach to nuclear conflict modeling and resolution. The author applies a Schelling test to segregate high from low empathic…

The Superpowers: Nuclear Weapons and National Security. National Issues Forums.

Science.gov (United States)

Mitchell, Greg; Melville, Keith

Designed to stimulate thinking about United States-Soviet relationships in terms of nuclear weapons and national security, this document presents ideas and issues that represent differing viewpoints and positions. Chapter 1, "Rethinking the U.S.-Soviet Relationship," considers attempts to achieve true national security, and chapter 2,…

Selective separation of radionuclides from nuclear waste solutions with inorganic ion exchangers

International Nuclear Information System (INIS)

Lehto, J.; Harjula, R.

1999-01-01

Nuclear industry produces and stores large volumes of radioactive waste solutions. Removal of radionuclides from the solutions is an important and challenging task for two main reasons: reductions in the volumes of solidified waste, which have to be disposed of, and reductions in the radioactive discharges into the environment. Since the radioactive elements in most waste solutions are in trace concentrations and the waste solutions contain large excesses of inactive metal ions, highly selective separation methods are needed for the removal of radionuclides. A number of inorganic ion exchange materials are very selective to key radionuclides and they can play an important role in solving these problems. The spectrum of nuclear waste solutions is rather wide considering their radionuclide contents, concentrations of interfering salts and acidity/alkalinity. Therefore, several inorganic ions exchangers are needed for the removal of most harmful radionuclides from a variety of solutions. This paper discusses the use and requirements of inorganic ion exchange materials in nuclear waste management. Special attention is paid to the novel ion exchange materials developed in the Laboratory of Radiochemistry, University of Helsinki. (orig.)

Numerical simulation of flow field in shellside of heat exchanger in nuclear power plant

International Nuclear Information System (INIS)

Wang Xinliang; Qiu Jinrong; Gong Zili

2010-01-01

Heat exchanger is the important equipment of nuclear power plant. Numerical simulation can give the detail information inside the heat exchange, and has been an effective research method. The geometric structure of shell-and-tube heat exchanger is very complex and it is difficult to simulate the whole flow field presently. According to the structure characteristics of the heat exchanger, a periodic whole-section calculation model was presented. The numerical simulation of flow field in shellside of heat exchange of a nuclear power plant was done by using this model. The results of simulation show that heat transfer in the periodic section of the heat exchange is uniform, the heat transfer is enhanced by using baffles in heat exchange, and frictional resistance is primary from the effect of segmental baffles. (authors)

Atmospheric effects and societal consequences of regional scale nuclear conflicts and acts of individual nuclear terrorism

Science.gov (United States)

Toon, O. B.; Turco, R. P.; Robock, A.; Bardeen, C.; Oman, L.; Stenchikov, G. L.

2007-04-01

We assess the potential damage and smoke production associated with the detonation of small nuclear weapons in modern megacities. While the number of nuclear warheads in the world has fallen by about a factor of three since its peak in 1986, the number of nuclear weapons states is increasing and the potential exists for numerous regional nuclear arms races. Eight countries are known to have nuclear weapons, 2 are constructing them, and an additional 32 nations already have the fissile material needed to build substantial arsenals of low-yield (Hiroshima-sized) explosives. Population and economic activity worldwide are congregated to an increasing extent in megacities, which might be targeted in a nuclear conflict. We find that low yield weapons, which new nuclear powers are likely to construct, can produce 100 times as many fatalities and 100 times as much smoke from fires per kt yield as previously estimated in analyses for full scale nuclear wars using high-yield weapons, if the small weapons are targeted at city centers. A single "small" nuclear detonation in an urban center could lead to more fatalities, in some cases by orders of magnitude, than have occurred in the major historical conflicts of many countries. We analyze the likely outcome of a regional nuclear exchange involving 100 15-kt explosions (less than 0.1% of the explosive yield of the current global nuclear arsenal). We find that such an exchange could produce direct fatalities comparable to all of those worldwide in World War II, or to those once estimated for a "counterforce" nuclear war between the superpowers. Megacities exposed to atmospheric fallout of long-lived radionuclides would likely be abandoned indefinitely, with severe national and international implications. Our analysis shows that smoke from urban firestorms in a regional war would rise into the upper troposphere due to pyro-convection. Robock et al. (2007) show that the smoke would subsequently rise deep into the stratosphere due

Tropospheric response to a nuclear exchange

International Nuclear Information System (INIS)

Penner, J.E.

1983-10-01

The immediate effects of a full-scale nuclear war would be large and severe. The survivors of such a war would have to endure possible changes in the chemical structure of the atmosphere. These changes may come about as a result of changes caused by the nuclear explosions themselves (direct effects) or as a result of changes caused by fires that may start after the explosions (indirect effects). This paper focuses on the expected global-scale changes in the chemical structure of the atmosphere from both direct and indirect effects after a full-scale nuclear exchange. The immediate effects of a nuclear explosion include the creation of a hot mass of air or fireball which rises in the atmosphere to a level that depends on the yield of the explosion. Because the fireball is hot, it is able to dissociate atmospheric nitrogen, N 2 . As the fireball cools, nitrogen atoms recombine with oxygen to form nitrogen oxides, NO and NO 2 . In addition, dust and recondensed gases are swept up through the stem of the fireball and deposited at the same level to which the fireball rises. This paper focuses on the response of atmospheric ozone to a nuclear war

Prolegomena to a theory of nuclear information exchange

International Nuclear Information System (INIS)

Van Nuffelen, Dominique

1997-01-01

From the researcher's point of view, the communications with the agricultural populations in case of radiological emergency can not be anything else but the application of a theory of nuclear information exchange among social groups. Consequently, it is essentially necessary to work out such a theory, the prolegomena of which are exposed in this paper. It describes an experiment conducted at 'Service de protection contre les radiations ionisantes' - Belgium (SPRI), and proposes an investigation within the scientific knowledge in this matter. The available empirical and theoretical data allow formulating pragmatic recommendations, among which the principal one is the necessity of creating in normal radiological situation of a number of scenarios of messages adapted to the agricultural populations. The author points out that in order to be perfectly adapted these scenarios must been negotiated between the emitter and receiver. If this condition is satisfied the information in case of nuclear emergency will really be an exchange of knowledge between experts and the agricultural population i.e. a 'communication'

Next Generation Nuclear Plant Intermediate Heat Exchanger Acquisition Strategy

Energy Technology Data Exchange (ETDEWEB)

Mizia, Ronald Eugene [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2008-04-01

DOE has selected the High Temperature Gas-cooled Reactor (HTGR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production. It will have an outlet gas temperature in the range of 900°C to 950°C and a plant design service life of 60 years. The reactor design will be a graphite moderated, helium cooled, prismatic or pebble-bed reactor, and use low-enriched uranium, TRISO-coated fuel. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Materials Research and Development (R&D) Program is responsible for performing R&D on likely NGNP materials in support of the NGNP design, licensing, and construction activities. Selection of the technology and design configuration for the NGNP must consider both the cost and risk profiles to ensure that the demonstration plant establishes a sound foundation for future commercial deployments. The NGNP challenge is to achieve a significant advancement in nuclear technology while at the same time setting the stage for an economically viable deployment of the new technology in the commercial sector soon after 2020. The purpose of this report is to address the acquisition strategy for the NGNP Intermediate Heat Exchanger (IHX).This component will be operated in flowing, impure helium on the primary and secondary side at temperatures up to 950°C. There are major high temperature design, materials availability, and fabrication issues that need to be addressed. The prospective materials are Alloys 617, 230, 800H and X, with Alloy 617 being the leading candidate for the use at 950°C. The material delivery schedule for these materials does not pose a problem for a 2018 start up as the vendors can quote reasonable delivery times at the moment. The product forms and amount needed must be finalized as soon as possible. An

Nuclear structure and the single charge exchange

International Nuclear Information System (INIS)

Oset, E.; Strottman, D.

1979-01-01

The influence of nuclear structure on meson-induced single-charge-exchange reactions on light nuclei is discussed within the context of the Glauber approximation. Selection rules which are expected to be approximately obeyed in elastic and inelastic pion and kaon scattering are proposed. Theoretical predictions are presented for (π + ,π 0 ) and (K + ,K 0 ) reactions on 13 C. 14 figures

Strategic nuclear policy and ballistic missile defense

International Nuclear Information System (INIS)

1981-01-01

The article explains the problems of the antirockets (ABM) as they were part of the presentation Salt I 1972. It is a translation from the English of a publication of the Foreign Affairs Research Institute in London. A topical analysis of the strategic nuclear policy of the two superpowers and their attitudes in the question of ballistic missile defense are given by means of two monographies. (orig./HSCH) [de

Operation control device for a nuclear reactor fuel exchanger

International Nuclear Information System (INIS)

Aida, Takashi.

1984-01-01

Purpose: To provide a operation control device for a nuclear reactor fuel exchanger with reduced size and weight capable of optionally meeting the complicated and versatile mode of the operation scope. Constitution: The operation range of a fuel exchanger is finely divided so as to attain the state capable of discriminating between operation-allowable range and operation-inhibitive range, which are stored in a memory circuit. Upon operating the fuel exchanger, the position is detected and a divided range data corresponding to the present position is taken out from the memory circuit so as to determine whether the fuel exchanger is to be run or stopped. Use of reduced size and compact IC circuits (calculation circuit, memory circuit, data latch circuit) and input/output interface circuits or the likes contributes to the size reduction of the exchanger control system to enlarge the floor maintenance space. (Moriyama, K.)

Quark exchange and nuclear dynamics

International Nuclear Information System (INIS)

Moniz, E.J.

1985-01-01

This paper gives a qualitative understanding of hadronic phenomena in terms of quark degrees of freedom. The basic model which incorporates saturating confining interactions and the study of hadron-hadron scattering has been carried through in collaboration with F. Lenz, J.T. Londergan, R. Rosenfelder, M. Stingl and K. Yazaki. It is shown that minimal confining dynamics together with exchange symmetry indeed leads to a remarkable range of phenomena at both the nuclear and particle energy scales. Most observables are well described by an effective hadron theory, the quark momentum distribution being the major exception. These features emerge even in the simplest model, namely, U(1) color and hadrons composed of two quarks (anti qq or qq). The author concentrates here on this model. In the concluding section, he remarks on the SU(N) results, particularly on the extent to which the color-hidden dynamics are constrained by examining the systematics of nuclear and hadronic phenomena. (Auth.)

Nuclear charge-exchange excitations in a self-consistent covariant approach

International Nuclear Information System (INIS)

Liang, Haozhao

2010-01-01

Nowadays, charge-exchange excitations in nuclei become one of the central topics in nuclear physics and astrophysics. Basically, a systematic pattern of the energy and collectivity of these excitations could provide direct information on the spin and isospin properties of the in-medium nuclear interaction, and the equation of state of asymmetric nuclear matter. Furthermore, a basic and critical quantity in nuclear structure, neutron skin thickness, can be determined indirectly by the sum rule of spin-dipole resonances (SDR) or the excitation energy spacing between the isobaric analog states (IAS) and Gamow-Teller resonances (GTR). More generally, charge-exchange excitations allow one to attack other kinds of problems outside the realm of nuclear structure, like the description of neutron star and supernova evolutions, the β-decay of nuclei which lie on the r-process path of stellar nucleosynthesis, and the neutrino-nucleus cross sections. They also play an essential role in extracting the value of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element V ud via the nuclear 0 + → 0 + superallowed Fermi β decays. For all these reasons, it is important to develop the microscopic theories of charge-exchange excitations and it is the main motivation of the present work. In this work, a fully self-consistent charge-exchange relativistic random phase approximation (RPA) based on the relativistic Hartree-Fock (RHF) approach is established. Its self-consistency is verified by the so-called IAS check. This approach is then applied to investigate the nuclear spin-isospin resonances, isospin symmetry-breaking corrections for the superallowed β decays, and the charged-current neutrino-nucleus cross sections. For two important spin-isospin resonances, GTR and SDR, it is shown that a very satisfactory agreement with the experimental data can be obtained without any readjustment of the energy functional. Furthermore, the isoscalar mesons are found to play an essential role in spin

Evolution of Soviet Theater Nuclear Forces

International Nuclear Information System (INIS)

Atkeson, E.B.

1994-01-01

Soviet theater nuclear forces were a major pillar of Soviet superpower strength, rising sharply under Krushchev in the latter 1950s to their zenith under Brezhnev twenty years later. Most recently they have begun their decline under Gorbachev, and while not yet facing extinction, may be headed for a much reduced role under the new thinking in the USSR. This paper deals with the Soviet TNF in six periods of their life: The Post-war Stalin Period (1945-1953), the Post-Stalin Period (1953-1955), The Transition Period (1955-1959), The Period of Nuclear Revolution (1960-1964), The Period of Modern TNF Planning (1965-1980), and The Period of Non-nuclear Planning (1980-1987)

Ion exchange and adsorption in nuclear chemical engineering

International Nuclear Information System (INIS)

Schultz, W.W.; Wheelwright, E.J.; Godbee, H.; Mallory, C.W.; Burney, G.A.; Wallace, R.M.

1983-01-01

The nuclear industry involves a number of operations. Uranium ore must first be mined and the uranium recovered from the ore, purified, and concentrated. After the uranium has been enriched and fabricated into fuel elements, it is placed in nuclear reactors where it produces energy, fission products, and transmutation products. Finally, if the fuel cycle is completed, the uranium and useful transmutation products are recovered and separated from each other as well as from the fission products. The uranium may be recycled or used elsewhere, while most of the fission products become waste. Ion exchange finds use in nearly every part of the nuclear fuel cycle; these uses are the subject of this paper

Information Exchange of the Atomic Energy Society of Japan with Nuclear Societies Worldwide

International Nuclear Information System (INIS)

Masao Hori; Yasushi Tomita

2000-01-01

This paper describes committees of the Atomic Energy Society of Japan (AESJ) related to information exchange, AESJ publications, AESJ Internet applications, and means for future information exchange between nuclear societies

Boson-exchange nucleon-nucleon potential and nuclear structure

International Nuclear Information System (INIS)

Grange, Pierre.

1976-01-01

A fully momentum-dependent one-boson-exchange potential is derived which takes into account the mesons, π, eta, sigma, rho, ω and phi. Scattering bound states and nuclear matter properties are studied in momentum space. The use of such potential is shown to be as easy as the use of more simple phenomenological interactions. In nuclear matter the formalism of Bethe-Goldstone is chosen to compute the binding energy versus density in the approximation of two-body and three-body correlations. The three-body correlated wave function obtained is then used [fr

Nuclear disarmament: France as a model; Desarmement nucleaire: prendre la France pour modele

Energy Technology Data Exchange (ETDEWEB)

Wodka-Gallien, Philippe [Institut francais d' analyse strategique, 12-14 rue du general Niox, 75016 Paris (France)

2012-02-15

The path taken by the French nuclear weapon programme shows unceasing pragmatism combined with a will to maintain the deterrence capability of the arsenal and the position it accords the country in the world's strategic structure. The abolition recommended by the US President would leave military matters open to conventional superpowers

The Indian nuclear test in a global perspective

International Nuclear Information System (INIS)

Subrahmanyam, K.

1974-01-01

A peaceful nuclear explosion test was carried out by India on 18 May, 1974 at Pokharan in the Rajasthan Desert. The test was carried out as a part of India's steady programme to develop nuclear energy for peaceful purposes and there was no diversion of resources from development as is charged by some nations. The test has broken the monopoly of the nuclear superpowers to conduct nuclear tests for which they are entiltled by the Non-proliferation Treaty (NPT) and at the same time, sharply focussed the attention on the discriminatory character of the NPT which does not allow non-nuclear states to carry out nuclear tests even for peaceful purposes. It is argued that India's going nuclear may prove, in the long run, beneficial to the cause of disarmament. (M.G.B.)

UFOs and nukes. Extraordinary encounters at nuclear weapons sites

International Nuclear Information System (INIS)

Hastings, Robert L.

2015-01-01

Everyone knows about the reported recovery of a crashed alien spaceship near Roswell, New Mexico in July 1947. However, most people are unaware that, at the time of the incident, Roswell Army Airfield was home to the world's only atomic bomber squadron, the 509th Bomb Group. Was this merely a coincidence? During the Cold War, the United States and the Soviet Union built thousands of the far more destructive hydrogen bombs, some of them a thousand times as destructive as the first atomic bombs dropped on Japan. If the nuclear standoff between the superpowers had erupted into World War III, human civilization - and perhaps the very survival of our species - would have been at risk. Did this ominous state of affairs come to the attention of outside observers? Was there a connection between the atomic bomber squadron based at Roswell and the reported crash of a UFO nearby? Did those who pilot the UFOs monitor the superpowers' nuclear arms race during the dangerous Cold War era? Do they scrutinize American and Russian weapons sites even now? UFOs and Nukes provides the startling and sometimes shocking answers to these questions. Veteran researcher Robert Hastings has investigated nuclear weapons-related UFO incidents for more than three decades and has interviewed more than 120 ex-US Air Force personnel, from former Airmen to retired Colonels, who witnessed extraordinary UFO encounters at nuclear weapons sites. Their amazing stories are presented here.

Preliminary study on high temperature heat exchanger for nuclear steel making

Energy Technology Data Exchange (ETDEWEB)

Nakada, T; Ohtomo, A; Yamada, R; Suzuki, K; Narita, Y [Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan)

1975-05-01

Both in the high temperature heat exchanger and in the steam reformer, there remain several technical problems to be solved before nuclear steel making is actualized. The loop for use with basic studies of those problems was planned by the Iron and Steel Institute of Japan (ISIJ), and its actual design, construction and co-ordination of tests were undertaken by IHI on behalf of ISIJ. The primary coolant used in the loop was helium having a pressure of approx. 12 kg/cm/sup 2/g and a temperature of approx. 1100/sup 0/C at the inlet of the high temperature heat exchanger, i.e., the test section. Steam, hydrogen, and carbon monoxide were used as secondary coolants. Of the technical problems regarding the high temperature heat exchanger for nuclear steel making, which were selected and studied using the loop, the following items are discussed: (1) heat exchange performance using helium and steam; (2) hydrogen permeation of heat resisting alloys; (3) creep and carburization of heat resisting alloys; amd (4) hydrogen absorption performance of the titanium sponge.

EXFOR basics. A short guide to the nuclear reaction data exchange format

International Nuclear Information System (INIS)

McLane, Victoria

2000-01-01

EXFOR is the agreed exchange format for the transmission of experimental nuclear reaction data between national and international nuclear data centers for the benefit of nuclear data users in all countries. This report is intended as a guide to data users. For a complete guide to the EXFOR system see: EXFOR Systems Manual, IAEA-NDS-207 (BNL-NCS-63330-00/04-Rev.) (author)

EXFOR systems manual: Nuclear reaction data exchange format. Revision 97/1

International Nuclear Information System (INIS)

McLane, V.

1997-07-01

This document describes EXFOR, the exchange format designed to allow transmission of nuclear reaction data between the members of the Nuclear Data Center Network. In addition to storing the data and its' bibliographic information, experimental information, including source of uncertainties, is also compiled. The status and history of the data set is also included, e.g., the source of the data, any updates which have been made, and correlations to other data sets. EXFOR is designed for flexibility rather than optimization of data processing in order to meet the diverse needs of the nuclear reaction data centers. The exchange format should not be confused with a center-to-user format. Although users may obtain data from the centers in the EXFOR format, other center-to-user formats have been developed to meet the needs of the users within each center's own sphere of responsibility. The exchange format, as outlined, is designed to allow a large variety of numerical data tables with explanatory and bibliographic information to be transmitted in an easily machine-readable format (for checking and indicating possible errors) and a format that can be read by personnel (for passing judgment on and correcting any errors indicated by the machine)

A nuclear free southeast Asia - the China factor

International Nuclear Information System (INIS)

Malik, J.M.

1989-01-01

It is estimated that the principal nuclear threat to Southeast Asia comes from nuclear weapons stored by the two superpowers in their respective bases and their targeting of each other's bases. Calls for the creation of a nuclear weapons free zone in Southeast Asia (SEANFZ) poses a number of problems to China because of the perceived negative impact of such zones on Chinese security interests, force deployment and strategic doctrine. Hence, it is argued that China is unlikely to support a nuclear free zone treaty which only embraces the Asean states because it would lead to unilateral disarmament on the part of pro-western countries while leaving Indochinese states and the Soviet Union. However, if the proposed SEANFZ treaty resembles the South Pacific Nuclear Free Zone treaty, which allow the transit of nuclear-armed vessels, China could be expected to support it. ills

New sorbents and ion exchangers for nuclear waste solution remediation

International Nuclear Information System (INIS)

Clearfield, A.; Peng, G.Z.; Cahill, R.A.; Bellinghausen, P.; Aly, H.I.; Scott, K.; Wang, J.D.

1993-01-01

There is now a concerted effort underway to clean up the accumulated nuclear wastes as the major sites around the country. Because of the complexity of the mixtures in the holding tanks highly specific exchangers are required to fulfill a multitude of desired tasks. These include removal of Cs + , Sr 2+ , Tc, Actinides and possible recovery of rare and precious metals. No one exchanger or sequestrant can accomplish these tasks and a variety of exchangers in a multistep process will be required. The behavior of a number of inorganic ion exchangers in a multistep process will be required. The behavior of a number of inorganic ion exchangers and new organo-inorganic exchangers towards Cs + , Sr 2+ and rare-earth ions in acid and basic media will be described. Preliminary data on the effect of high levels of sodium nitrate on the uptake of these ions will also be presented, as well as the changes observed in selectivity in simulated waste solutions. A possible separation scheme based on these data will be described

Study on a program for support of women nuclear experts exchange and mutual utilization between WANO Korea and WANO Global

International Nuclear Information System (INIS)

Lee, Haecho; No, Inyoung; Min, Byungju

2010-12-01

- Nuclear energy, unlike other international human and material essential to mutual understanding, exchange of information and technology-intensive industries as required by an active technical cooperation and information exchange between countries is very important - WiN-Global Women's Domestic Nuclear specialists and professionals between countries belonging to the network for women through nuclear technology and nuclear power expansion opportunities to exchange information to secure a variety of communication

Some fabrication problems in nuclear power plants heat exchanges, its detectability and implications

International Nuclear Information System (INIS)

Condessa, N.C.; Oliveira, R.

1988-01-01

On the design and manufacturing follow-up of heat-exchangers of nuclear power plants some care are took into account in order to assure a high degree of confiability allowing the heat-exchanger in operation under severe and aggressive conditions be operating during the useful life of the nuclear power plant. However, despite the care, some problems can ocurr as the ones described on this job; that, if not detected in due time could bring umpleasant problems to the component or to the system in which it is working during operation. (author) [pt

Information exchange of the Atomic Energy Society of Japan with nuclear societies worldwide

International Nuclear Information System (INIS)

Hori, Masao; Tomita, Yasushi

2000-01-01

The Atomic Energy Society of Japan (AESJ) exchanges information with nuclear societies worldwide by intersocietal communication through international councils of nuclear societies and through bilateral agreements between foreign societies and by such media as international meetings, publications, and Internet applications

International exchange of radiological information in the event of a nuclear accident - future perspectives

International Nuclear Information System (INIS)

De-Cort, M.; De-Vries, G.; Breitenbach, L.; Leeb, H.; Weiss, W.

1996-01-01

Immediately after the Chernobyl accident most European countries established or enhanced their national radioactivity monitoring and information systems. The large transboundary effect of the radioactive release also triggered the need for bilateral and international agreements on the exchange of radiological information in case of a nuclear accident. Based on the experiences gained from existing bi- and multilateral data exchange the Commission of the European Communities has made provision for and is developing technical systems to exchange information of common interest. Firstly the existing national systems and systems based on bilateral agreements are summarized. The objectives and technical realizations of the EC international information exchange systems ECURIE and EURDEP, are described. The experiences gained over the past few years and the concepts for the future, in which central and eastern European countries will be included, are discussed. The benefits that would result from improving the international exchange of radiological information in the event of a future nuclear accident are further being described

Nuclear war: preliminary estimates of the climatic effects of a nuclear exchange

International Nuclear Information System (INIS)

MacCracken, M.C.

1983-10-01

The smoke rising from burning cities, industrial areas, and forests if such areas are attacked as part of a major nuclear exchange is projected to increase the hemispheric average atmospheric burden of highly absorbent carbonaceous material by 100 to 1000 times. As the smoke spreads from these fires, it would prevent sunlight from reaching the surface, leading to a sharp cooling of land areas over a several day period. Within a few weeks, the thick smoke would spread so as to largely cover the mid-latitudes of the Northern Hemisphere, cooling mid-continental smoke-covered areas by, perhaps, a few tens of degrees Celsius. Cooling of near coastal areas would be substantially less, since oceanic heat capacity would help to buffer temperature changes in such regions. The calculations on which these findings are based contain many assumptions, shortcomings and uncertainties that affect many aspects of the estimated response. It seems, nonetheless, quite possible that if a nuclear exchange involves attacks on a very large number of cities and industrial areas, thereby starting fires that generate as much smoke as is suggested by recent studies, substantial cooling could be expected that would last weeks to months over most continental regions of the Northern Hemisphere, but which may have relatively little direct effect on the Southern Hemisphere

Off-shell pairing correlations from meson-exchange theory of nuclear forces

International Nuclear Information System (INIS)

Sedrakian, Armen

2003-01-01

We develop a model of off-mass-shell pairing correlations in nuclear systems, which is based on the meson-exchange picture of nuclear interactions. The temporal retardations in the model are generated by the Fock-exchange diagrams. The kernel of the complex gap equation for baryons is related to the in-medium spectral function of mesons, which is evaluated nonperturbatively in the random phase approximation. The model is applied to the low-density neutron matter in neutron star crusts by separating the interaction into a long-range one-pion-exchange component and a short-range component parametrized in terms of Landau Fermi liquid parameters. The resulting Eliashberg-type coupled nonlinear integral equations are solved by an iterative procedure. We find that the self-energies extend to off-shell energies of the order of several tens of MeV. At low energies the damping of the neutron pair correlations due to the coupling to the pionic modes is small, but becomes increasingly important as the energy is increased. We discuss an improved quasiclassical approximation under which the numerical solutions are obtained

Nuclear disarmament - A consultants observations

International Nuclear Information System (INIS)

Stoll, W.

2003-01-01

The changed situation in the conflict between the superpowers after the end of the Cold War requires a reduction in the excessive number of weapon systems, especially of nuclear weapons of mass destruction. While the U.S. approach is relatively transparent, Russia harbors a large number of administrative and technical reservations and uncertainties. This affects the nuclear fuel cycle in particular. The contribution analyzes the general boundary conditions, taking into account experience accumulated on the spot in a number of trips to Russia in the course of the past decade. A detailed account is given of the current situation in the civilian and military nuclear sectors in Russia. The state of development and the problems of the Russian nuclear fuel cycle are addressed. Other items discussed are aspects of the future nuclear fuel supply situation and other perspectives of the use of nuclear power in Russia associated with an establishment of closed nuclear fuel cycles in the interest of the long-term continuity of power supply. (orig.) [de

Non proliferation of nuclear weapons?

International Nuclear Information System (INIS)

Le Guelte, Georges

2015-10-01

After having evoked the behaviour of nuclear countries regarding the development of nuclear weapons and uranium procurement, or nuclear programmes after the Second World War until nowadays, the author presents the non proliferation Treaty (NPT) as a construction at the service of super-powers. He comments and discusses the role of the IAEA control system and its evolutions: a control limited to declared installations, an export control with the spectre of plutonium, a control system thwarted by some technological innovations, information systems coming in, and an additional protocol related to the application of guarantees. He comments the evolution of the context from a bipolar world to a world without pole which raises the issue of how to have commitments respected: description of the role and practice of non proliferation during the Cold War, after the Cold War, and in a world without governance

Common sense and nonproliferation

International Nuclear Information System (INIS)

Kennedy, R.T.

1985-01-01

Since the dawn of the nuclear age nearly four decades ago, the United States has been firmly commited to the objective of preventing the spread of nuclear weapons. That principle is embodied in the Nonproliferation Treaty (NPT), support for which has been a basic tenet of US foreign policy and a basic security interest of the world at large ever since. The Reagan administration remains firmly committed to the goal of preventing the spread of nuclear weapons. Such proliferation could trigger new and grave dangers for America's security and well-being and indeed for that of all the world's peoples. Desperate leaders in future high-stakes conflicts might not shrink from nuclear blackmail or even from the use of nuclear weapons if they were available. A conventional clash between nuclear-armed states in a conflict-prone region might escalate by accident or miscalculation to a local nuclear exchange. It cannot be discounted that such a nuclear clash might threaten to involve the superpowers themselves. With proliferation, also, terrorist groups could more easily acquire nuclear weapons to extort concessions. Preventing the spread of nuclear weapons, then, is not solely of interest to the superpowers: it is vital to all countries and regions. The security of the countries in those regions to which nuclear weapons might spread would be most immediately and seriously affected. By their adherence to the NPT, more than 100 countries have recognized this fact

Preliminary study on high temperature heat exchanger for nuclear steel making

Energy Technology Data Exchange (ETDEWEB)

Mori, Y [Tokyo Inst. of Tech. (Japan); Ikegami, H

1975-03-01

In the high temperature heat exchanger as well as the steam reformer, several technical problems should be solved before realizing a nuclear plant complex for iron and steel making. Research has been carried out on heat exchanger between helium and steam, hydrogen permeation through super alloys, hydrogen removal using a titanium sponge, and creep and carburization performance of super alloys. The primary coolant used is helium having a pressure of approximately 12 kg/cm/sup 2/G and a temperature of approximately 1100/sup 0/C measured at the inlet of the high temperature heat exchanger, i.e., the test section. Steam, hydrogen and carbon monoxide are used as secondary coolants.

After fifty years of the nuclear age: Non-proliferation of nuclear weapons or elimination of them?

International Nuclear Information System (INIS)

Sugie, Ei-Ichi

1997-01-01

Ever since the first test of the atomic bomb and the bombing of Hiroshima and Nagasaki in 1945, mankind lived with nuclear weapons. Nuclear weapons were inevitably connected with the Cold War, with its end new opportunity has come concerning prohibition of the use of nuclear weapons. Steps are to be undertaken in order to eliminate the nuclear weapons. First, would be the prohibition of the use or the threat of use of nuclear weapons. By excluding the possibility of the use of nuclear weapons, the world could be closer to nuclear disarmament than ever. The prohibition of the use of some type of weapons could be a breakthrough towards the elimination of such weapons. While the negotiations to eliminate nuclear weapons would be difficult, as were those to ban chemical weapons, a ban on the use of nuclear weapons would eventually lead to their elimination. During the Cold War, the imminent goal of disarmament was to stop the nuclear arms race between the two superpowers. But in the post-Cold War era an opportunity has developed for further steps towards nuclear disarmament, the elimination of nuclear weapons

Expectations and realities in the nuclear technology exchanges with the USSR

Energy Technology Data Exchange (ETDEWEB)

Lewin, J.

1980-01-01

A nontechnical, subjective account is given of some of the experiences and personal encounters in the US-USSR technical exchange visit programs. Some notes are given on the growth of nuclear power in the two countries. (DLC)

New Anion-Exchange Resins for Improved Separations of Nuclear Materials

International Nuclear Information System (INIS)

Bartsch, Richard A.; Barr, Mary E.

2001-01-01

Improved separations of nuclear materials will have a significant impact upon a broad range of DOE activities. DOE-EM Focus Areas and Crosscutting Programs have identified improved methods for the extraction and recovery of radioactive metal ions from process, waste, and environmental waters as critical needs for the coming years. We propose to develop multifunctional anion-exchange resins that facilitate anion uptake by carefully controlling the structure of the anion receptor site. Our new ion-exchange resins interface the field of ion-specific chelating ligands with robust, commercial ion-exchange technology to provide materials which exhibit superior selectivity and kinetics of sorption and desorption. The following Focus Areas and Crosscutting Programs have described needs that would be favorably impacted by the new material: Efficient Separations and Processing - radionuclide removal from aqueous phases; Plutonium - Pu, Am or total alpha removal to meet regulatory requirement s before discharge to the environment; Plumes - U and Tc in groundwater, U, Pu, Am, and Tc in soils; Mixed Waste - radionuclide partitioning; High-Level Tank Waste - actinide and Tc removal from supernatants and/or sludges. The basic scientific issues which need to be addressed are actinide complex speciation along with modeling of metal complex/functional site interactions in order to determine optimal binding-site characteristics. Synthesis of multifunctionalized extractants and ion-exchange materials that implement key features of the optimized binding site, and testing of these materials, will provide feedback to the modeling and design activities. Resin materials which actively facilitate the uptake of actinide complexes from solution should display both improved selectivity and kinetic properties. The long-range implications of this research, however, go far beyond the nuclear complex. This new methodology of ''facilitated uptake'' could revolutionize ion-exchange technology

International collaboration on inherently safe nuclear reactors

International Nuclear Information System (INIS)

Barkenbus, J.N.

1989-01-01

Science and technology transcend economic and political ideologies, providing a means of communications and approach common to both the United States and the Soviet Union. This paper suggests that the field of nuclear fission is a logical and productive area for superpower and broader collaboration, but that the kind of collaboration characteristic of past and present activity is less than it optimally could be. The case for cost sharing is compelling with budget constraints and mounting concerns over global warming. The case for collaboration is based on economic, psychological, and political grounds. A collaborative effort in nuclear fission is presented as a near term effort by building and testing of a prototype reactor in the 1990s

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

EXFOR basics: A short guide to the nuclear reaction data exchange format

International Nuclear Information System (INIS)

McLane, V.

1996-07-01

This manual is intended as a guide to users of nuclear reaction data compiled in the EXFOR format, and is not intended as a complete guide to the EXFOR System. EXFOR is the exchange format designed to allow transmission of nuclear data between the Nuclear Reaction Data Centers. In addition to storing the data and its' bibliographic information, experimental information, including source of uncertainties, is also compiled. The status and history of the data set is also included, e.g., the source of the data, any updates which have been made, and correlations to other data sets. EXFOR is designed for flexibility in order to meet the diverse needs of the nuclear data compilation centers. This format should not be confused with a center-to-user format. Although users may obtain data from the centers in the EXFOR format, other center-to-user formats have been developed to meet the needs of the users within each center's own sphere of responsibility. The exchange format, as outlined, allows a large variety of numerical data tables with explanatory and bibliographic information to be transmitted in an easily machine-readable format (for checking and indicating possible errors) and a format that can be read by personnel (for passing judgment on and correcting any errors indicated by the machine). The data presently included in the EXFOR exchange include: a complete compilation of experimental neutron-induced reaction data, a selected compilation of charged-particle induced reaction data, a selected compilation of photon-induced reaction data

Study of mineral ion exchangers for strontium removal from nuclear waste waters

International Nuclear Information System (INIS)

Merceille, A.

2012-01-01

The problems of chemical pollution of water have become a major concern and a priority for the nuclear industry. The aim of this work is to study some ion exchangers used for the removal of strontium ions because 90 Sr is one of a major pollutant in nuclear liquid wastes. This study allows linking the physical and chemical properties of these materials and their sorption properties. This work presents therefore the synthesis of two materials - sodium nona-titanate and zeolite A - selected for their specific sorption properties of strontium: A second part of this work is dedicated to the study of specific exchange capacities of these materials for the strontium in presence of other elements such as sodium and calcium. Batch experiments were performed and kinetic and ion exchange models have been applied to understand the selectivity of the materials for strontium removal. Sodium nona-titanate and zeolite A are also studied in actual effluents. Monoliths of zeolite A have been also tested in dynamic ion exchange process. This material is promising for the treatment of radioactive effluents in continuous flow because it joins the sorption properties of the zeolite powder with the advantage of a solid with a macroporous network. (author) [fr

Knowledge Transfer and Culture Exchange between HEU and TAMU through a Summer School on Nuclear Power Engineering

International Nuclear Information System (INIS)

Gao, P.; Zhang, Z.; Kurwitz, R. C.; Shao, L.

2016-01-01

Full text: Since 2012, Harbin Engineering University (HEU) and Texas A&M University (TAMU) hold an annual Summer School on Nuclear Engineering. By now, the activity has been held four times. Each year, 15–20 students are selected from their respective institutions and paired with a counterpart to form partners. They study lectures in the first week at HEU and tour three nuclear power plants (NPP) in the second week, visit the NPP simulators, and learn the nuclear safety culture. This activity expands the scale of international nuclear educational exchange, provide a platform for the students from different countries to communicate and exchange insights into their respective culture. (author

Radionuclide separations in the nuclear fuel cycle development and application of micro and meso porous inorganic ion-exchangers

International Nuclear Information System (INIS)

Griffith, C.S.; Luca, V.

2006-01-01

Full text: Full text: From the mining of uranium-containing ores to the reprocessing of spent nuclear fuel, separations technologies play a crucial role in determining the efficiency and viability of the nuclear fuel cycle. With respect to proposed Advanced Nuclear Fuel Cycles (ANFC), the integral role of separations is no different with solvent extraction and pyroelectrometalurgical processing dominating efforts to develop a sustainable and publicly acceptable roadmap for nuclear power in the next 100 years. An often forgotten or overlooked separation technology is ion-exchange, more specifically, inorganic ion-exchangers. This is despite the fact that these materials offer the potential advantages of process simplicity; exceptional selectivity against high background concentrations of competing ions; and the possibility of a simple immobilization route for the separated radionculides. ANSTO's principal interest in inorganic ion-exchange materials in recent years has been the development of an inorganic ion-exchanger for the pretreatment of acidic legacy 9 Mo production waste to simultaneously remove radiogenic cesium and strontium. Radiogenic cesium and strontium comprise the majority of activity in such waste and may offer increased ease in the downstream processing to immobilise this waste in a Synroc wasteform. With the reliance on separations technologies in all current ANFC concepts, and the recent admission of ANSTO to the European Commissions EUROPART project, the development of new inorganic ion-exchangers has also expanded within our group. This presentation will provide a background of the fundamentals of inorganic and composite inorganic-organic ion-exchange materials followed by specific discussion of some selected inorganic and composite ion-exchange materials being developed and studied at ANSTO. The detailed structural and ion-exchange chemistry of these materials will be discussed and note made of how such materials could benefit any of the

Peaceful uses of nuclear weapon plutonium

International Nuclear Information System (INIS)

Burtak, F.

1996-01-01

In 1993, the U.S.A. and the CIS signed Start 2 (the Strategic Arms Reduction Treaty) in which they committed themselves the reduce their nuclear weapon arsenals to a fraction of that of 1991. For forty-five years the antagonism between the superpowers had been a dominating factor in world history, determining large areas of social life. When Start 2 will have been completed in 2003, some 200 t of weapon grade plutonium and some 2000 t of highly enriched uranium (Heu) will arise from dismantling nuclear weapons. In the absence of the ideological ballast of the debate about Communism versus Capitalism of the past few decades there is a chance of the grave worldwide problem of safe disposal and utilization of this former nuclear weapon material being solved. Under the heading of 'swords turned into plowshares', plutonium and uranium could be used for peaceful electricity generation. (orig.) [de

On the optimal design of shell and tube heat exchanger for nuclear applications

International Nuclear Information System (INIS)

Abd Rabbo, F.M.M.; Fatb Allab, A.; El-Fawal, M.

1997-01-01

In nuclear industry, heat exchanger plays an important role in the transfer of heat from reactor core, where heat is generated, to the ultimate heat sink UHS, and then is dissipated. The actual design of heat exchanger not only relies on thermohydraulic considerations but also on economical aspects and radiological safety considerations. For optimal design of heat exchanger for a specific application a compromise should be made for determining the important factors affecting the design. In this paper, an optimization model is presented for shell and tube heat exchanger, which could be considered as a tool for computer aided design. A case study is presented to explore the present adopted model. 3 figs

The continuing nuclear challenge

International Nuclear Information System (INIS)

Karp, R.C.

1991-01-01

This paper reports that Declining threat perceptions in the superpower relationship make the need for compellent threats less pressing and reduce demands upon the credibility of extended deterrence. Nuclear arms control and reductions can create survivable forces forestalling all but irrational incentives for a first strike. Conventional arms control can restructure national armies to such an extent that crises can be weathered without recourse to arms, thus reducing the risk of nuclear escalation. The post-cold war era presents an opportunity to make meaningful progress in these areas and should serve to remind states that their security may not need to be based on the threat to use nuclear weapons. States that place a high status value on nuclear weapons and those at the nuclear threshold may not agree with this assessment. But if co-operative security structures can be found and acted upon, the allure of nuclear status may also decline. And, with an improving US-Soviet relationship, regional security problems that have led states to acquire nuclear weapons may become more amenable to solution by joint diplomatic initiatives. None of these measures are easily achievable not are they likely to be undertaken in a concerted fashion. However, unlike in the past, the post-cold war environment makes these steps feasible

A Scientific Assessment of the Atmospheric Impact of a Nuclear Exchange

Science.gov (United States)

Reisner, J. M.

2016-12-01

A nuclear exchange at either the regional or global scale will unfortunately lead to large loss of life; however, given the consequences it is important to scientifically quantify this problem and not over exaggerate impacts. Over the past 70 years Los Alamos has been developing the necessary expertize to quantify effects from nuclear weapons. In particular, the rapid advancement of computing power has enabled model calculations over a wide range of spatial and time scales from the source to cdimpacts. In this presentation, results from each scale will be presented along with discussions regarding the importance of the linkage between each scale. For example, source calculations are important for defining the spatial region where the weapon can start potential fires; a consequence of the thermal fluence, rubblization, and other factors such as cloud cover. This information is then used in a first principle urban firestorm model that simulates the production of carbon particles responsible for possible blockage of incoming solar radiation--the so-called nuclear winter mechanism. Hence, the critical piece of this puzzle is the overall carbon footprint that could lead to regional/global cooling; assuming either too much carbon and/or all carbon is transported into the stratosphere will lead to unrealistic estimates of cooling. And finally, another important aspect to be shown in this presentation is how a realistic source of carbon could lead to significant reductions in long-term regional/global impacts of a nuclear exchange.

Non-proliferation of nuclear weapons

International Nuclear Information System (INIS)

Fischer, D.; Haeckel, E.; Haefele, W.; Lauppe, W.D.; Mueller, H.; Ungerer, W.

1991-01-01

During the turbulant transitional events in world politics in the nineties, the control of nuclear weapons plays a major role. While the superpowers are reducing their nuclear arsenal, the danger of nuclear anarchy in the world remains virulent. The NPT of 1968 is up for review soon. The falling apart of the former communist sphere of power, and the regions of conflict in the Third World present new risks for the proliferation of nuclear arms. For unified Germany, which explicitly renounced nuclear weapons, this situation presents difficult questions concerning national safety policies and international responsibility. This volume presents contributions which take a new look at topical and long-term problems of nuclear NP politics. The authors evaluate the conditions under which the NP regime came into being, and assess short- and long-term possibilities and risks. The following papers are included: 1.) Basic controversies during the negotiations concerning the Treaty on non-proliferation of nuclear weapons (Ungerer); 2.) Prologation of the NPT 1995 and appropriate problems concerning safety and control (Haefele/Lauppe); 3.) Consequences of the Iraq case for NP policy (Ficher); 4.) Problems of nuclear technology control (Mueller); 5.) Framework conditions of a nuclear world system (Haeckel). (orig./HP) [de

Proliferation of nuclear weapons. Civilian and military exploitation of nuclear power

International Nuclear Information System (INIS)

Andresen, S.; Kongstad, S.

1978-01-01

Following brief technical and historical surveys the structure of the nuclear power market is discussed. In the 1970s a major change has been the decline of USA's virtual monopoly and the active entry of West Germany, France and Canada into the merket. Another development has been the commercialisation of progressively more of the fuel cycle, vide the agreements between Brazil and W. Germany, and Pakistan and France. These tendencies, added to the general spread of nuclear technologial ability and the adoption of nuclear power in more and more developing countries is presumed to increase the danger of nuclear weapon proliferation. The motives for, and means of, such proliferation are analysed. The tripartite agreement between Brazil, W. Germany and USA is discussed in great detail to illustrate the situation. The role of the NPT is not found to be significant. It is concluded that though proliferation may be inevitible, the motives may be for prestige and negotiating power, rather than use, and that the policy of the superpowers seems in the long run to lead to a reduction of their military dominance, and possible also their economic and political position in the international community. (JIW)

The evolution of American nuclear doctrine 1945-1980: from massive retaliation to limited nuclear war

International Nuclear Information System (INIS)

Richani, N.

1983-01-01

This thesis attempts to demonstrate the evolutionary character of American nuclear doctrine from the beginning of the nuclear age in 1945 until 1980. It also aims at disclosing some of the most important factors that contributed to the doctrine's evolution, namely, technological progress and developments in weaponry and the shifts that were taking place in the correlation of forces between the two superpowers, the Soviet Union and the United States. The thesis tries to establish the relation, if any, between these two variables (technology and balance of forces) and the evolution of the doctrine from Massive Retaliation to limited nuclear war. There are certainly many other factors which influenced military doctrine, but this thesis focuses on the above mentioned factors. touching on others when it was thought essential.The thesis concludes by trying to answer the question of whether the purpose of the limited nuclear war doctrine is to keep the initiative in US hands, that is putting itself on the side with the positive purpose, or not. Refs

The evolution of American nuclear doctrine 1945-1980: from massive retaliation to limited nuclear war

Energy Technology Data Exchange (ETDEWEB)

Richani, N [Public Administration Dpt. American Univ. of Beirut (Lebanon)

1983-12-31

This thesis attempts to demonstrate the evolutionary character of American nuclear doctrine from the beginning of the nuclear age in 1945 until 1980. It also aims at disclosing some of the most important factors that contributed to the doctrine`s evolution, namely, technological progress and developments in weaponry and the shifts that were taking place in the correlation of forces between the two superpowers, the Soviet Union and the United States. The thesis tries to establish the relation, if any, between these two variables (technology and balance of forces) and the evolution of the doctrine from Massive Retaliation to limited nuclear war. There are certainly many other factors which influenced military doctrine, but this thesis focuses on the above mentioned factors. touching on others when it was thought essential.The thesis concludes by trying to answer the question of whether the purpose of the limited nuclear war doctrine is to keep the initiative in US hands, that is putting itself on the side with the positive purpose, or not. Refs.

Neutrinoless ββ decay mediated by the exchange of light and heavy neutrinos: the role of nuclear structure correlations

Science.gov (United States)

Menéndez, J.

2018-01-01

Neutrinoless β β decay nuclear matrix elements calculated with the shell model and energy-density functional theory typically disagree by more than a factor of two in the standard scenario of light-neutrino exchange. In contrast, for a decay mediated by sterile heavy neutrinos the deviations are reduced to about 50%, an uncertainty similar to the one due to short-range effects. We compare matrix elements in the light- and heavy-neutrino-exchange channels, exploring the radial, momentum transfer and angular momentum-parity matrix element distributions, and considering transitions that involve correlated and uncorrelated nuclear states. We argue that the shorter-range heavy-neutrino exchange is less sensitive to collective nuclear correlations, and that discrepancies in matrix elements are mostly due to the treatment of long-range correlations in many-body calculations. Our analysis supports previous studies suggesting that isoscalar pairing correlations, which affect mostly the longer-range part of the neutrinoless β β decay operator, are partially responsible for the differences between nuclear matrix elements in the standard light-neutrino-exchange mechanism.

Annual harvests of Corbicula populations prevent clogging of nuclear reactor heat exchangers

International Nuclear Information System (INIS)

Harvey, R.S.

1983-01-01

An annual program for removal of millions of Corbicula from upstream cooling water basins has prevented reclogging of nuclear reactor heat exchanger distributor plates at the Savannah River Plant during the past seven years. There are nine 32-megaliter basins in the three operating reactor areas where some settling of particulates occurs before cooling water is passed through screens in route to heat exchangers. Annual cleanings keep silt/clam substrate levels low and clam sizes small. Data are presented on the size/age distribution for clams recolonizing basins between cleanings

Virtual superheroes: using superpowers in virtual reality to encourage prosocial behavior.

Directory of Open Access Journals (Sweden)

Robin S Rosenberg

Full Text Available BACKGROUND: Recent studies have shown that playing prosocial video games leads to greater subsequent prosocial behavior in the real world. However, immersive virtual reality allows people to occupy avatars that are different from them in a perceptually realistic manner. We examine how occupying an avatar with the superhero ability to fly increases helping behavior. PRINCIPAL FINDINGS: Using a two-by-two design, participants were either given the power of flight (their arm movements were tracked to control their flight akin to Superman's flying ability or rode as a passenger in a helicopter, and were assigned one of two tasks, either to help find a missing diabetic child in need of insulin or to tour a virtual city. Participants in the "super-flight" conditions helped the experimenter pick up spilled pens after their virtual experience significantly more than those who were virtual passengers in a helicopter. CONCLUSION: The results indicate that having the "superpower" of flight leads to greater helping behavior in the real world, regardless of how participants used that power. A possible mechanism for this result is that having the power of flight primed concepts and prototypes associated with superheroes (e.g., Superman. This research illustrates the potential of using experiences in virtual reality technology to increase prosocial behavior in the physical world.

UFOs and nukes. Extraordinary encounters at nuclear weapons sites; UFOs und Atomwaffen. Unheimliche Begegnungen in der Naehe von Nuklearwaffendepots

Energy Technology Data Exchange (ETDEWEB)

Hastings, Robert L.

2015-07-01

Everyone knows about the reported recovery of a crashed alien spaceship near Roswell, New Mexico in July 1947. However, most people are unaware that, at the time of the incident, Roswell Army Airfield was home to the world's only atomic bomber squadron, the 509th Bomb Group. Was this merely a coincidence? During the Cold War, the United States and the Soviet Union built thousands of the far more destructive hydrogen bombs, some of them a thousand times as destructive as the first atomic bombs dropped on Japan. If the nuclear standoff between the superpowers had erupted into World War III, human civilization - and perhaps the very survival of our species - would have been at risk. Did this ominous state of affairs come to the attention of outside observers? Was there a connection between the atomic bomber squadron based at Roswell and the reported crash of a UFO nearby? Did those who pilot the UFOs monitor the superpowers' nuclear arms race during the dangerous Cold War era? Do they scrutinize American and Russian weapons sites even now? UFOs and Nukes provides the startling and sometimes shocking answers to these questions. Veteran researcher Robert Hastings has investigated nuclear weapons-related UFO incidents for more than three decades and has interviewed more than 120 ex-US Air Force personnel, from former Airmen to retired Colonels, who witnessed extraordinary UFO encounters at nuclear weapons sites. Their amazing stories are presented here.

Dressed dibaryon production as a new mechanism for basic nuclear force and meson-exchange currents

International Nuclear Information System (INIS)

Kukulin, V.I.

2003-01-01

A novel concept for the nuclear force is introduced. The approach assumes that a specific dressed six-quark state (dressed dibaryon) is generated in NN collision at intermediate and short ranges. The new dressing mechanism providing π-, σ-, ρ- and ω-meson clouds around the six quark core is discussed. These novel components produce both strong intermediate-range attraction and short-range repulsion in the NN sector due to the s-channel exchange mechanism which is supplemented with conventional π- and 2π- Yukawa exchanges at intermediate and long ranges. The model developed is demonstrated to lead to numerous new effects and contributions in many fields of nuclear physics. (author)

Certification of materials for steam generator condensor and regeneration heat exchanger for nuclear plant

International Nuclear Information System (INIS)

Stevanovicj, M.V.; Jovashevicj, V.J.; Jovashevicj, V.D.J.; Spasicj, Zh.Lj.

1977-01-01

In the construction of a nuclear power plant almost all known materials are used. The choice depends on working conditions. In this work standard specifications of contemporary materials that take part in larger quantities in the following components of the secondary circuit of PWR-type nuclear power plant are proposed: steam generator with moisture separator, condensor and regenerative heat eXchanger

Characterization of Chemical Exchange Using Relaxation Dispersion of Hyperpolarized Nuclear Spins.

Science.gov (United States)

Liu, Mengxiao; Kim, Yaewon; Hilty, Christian

2017-09-05

Chemical exchange phenomena are ubiquitous in macromolecules, which undergo conformational change or ligand complexation. NMR relaxation dispersion (RD) spectroscopy based on a Carr-Purcell-Meiboom-Gill pulse sequence is widely applied to identify the exchange and measure the lifetime of intermediate states on the millisecond time scale. Advances in hyperpolarization methods improve the applicability of NMR spectroscopy when rapid acquisitions or low concentrations are required, through an increase in signal strength by several orders of magnitude. Here, we demonstrate the measurement of chemical exchange from a single aliquot of a ligand hyperpolarized by dissolution dynamic nuclear polarization (D-DNP). Transverse relaxation rates are measured simultaneously at different pulsing delays by dual-channel 19 F NMR spectroscopy. This two-point measurement is shown to allow the determination of the exchange term in the relaxation rate expression. For the ligand 4-(trifluoromethyl)benzene-1-carboximidamide binding to the protein trypsin, the exchange term is found to be equal within error limits in neutral and acidic environments from D-DNP NMR spectroscopy, corresponding to a pre-equilibrium of trypsin deprotonation. This finding illustrates the capability for determination of binding mechanisms using D-DNP RD. Taking advantage of hyperpolarization, the ligand concentration in the exchange measurements can reach on the order of tens of μM and protein concentration can be below 1 μM, i.e., conditions typically accessible in drug discovery.

Molecular exchange of n-hexane in zeolite sieves studied by diffusion-diffusion and T{sub 1}-diffusion nuclear magnetic resonance exchange spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Neudert, Oliver; Stapf, Siegfried; Mattea, Carlos, E-mail: carlos.mattea@tu-ilmenau.de [Fachgebiet Technische Physik II/Polymerphysik, Institute of Physics, Technische Universitaet Ilmenau, PO Box 100 565, 98684 Ilmenau (Germany)

2011-03-15

Molecular exchange properties and diffusion of n-hexane embedded in a bimodal pore structure with characteristic length scales in the order of nano and micrometres, respectively, formed by packing of zeolite particles, are studied. Two-dimensional (2D) nuclear magnetic resonance (NMR) diffusion correlation experiments together with relaxation-diffusion correlation experiments are performed at low magnetic field using a single-sided NMR scanner. The exchange time covers a range from 10{sup -3} to 10{sup -1} s. The molecular exchange properties are modulated by transport inside the zeolite particles. Different exchange regimes are observed for molecules starting from different positions inside the porous sample. The influence of the spin-lattice relaxation properties of the fluid molecules inside the zeolite particles on the signal intensity is also studied. A Monte Carlo simulation of the exchange process is performed and is used to support the analysis of the experimental data.

Beyond the Cold-War Reprise of the Arctic Super-Powers. Decoding the Structural Meaning of the Ukrainian Crisis

Directory of Open Access Journals (Sweden)

John McMurtry

2015-03-01

Full Text Available The “Ukraine crisis” repeats a script as old as the Cold War, of which the Arctic was one of its main theatres and that, as suggested by Irina Zhilina in her 2013 study about NATO in the far north for issue 8(1 of Nordicum-Mediterraneum, could regain such a role, were frictions between East and West to resurface. And they have resurfaced. The ongoing Cold-War-like narrative vis-à-vis Ukraine features rising attacks by corporate states and media on the traditional whipping boy of Russia. As usual, “escalating the crisis” is the other Arctic super-power: the US. As usual, alarm about “increasing lawless aggression” is projection of US policy itself.

Current status and development of heat exchangers for boiling water reactor nuclear power plant

International Nuclear Information System (INIS)

Uchiyama, Yoshio; Nishioka, Shuji; Ito, Shizuo

1975-01-01

More efficient and reliable operation is required for BWR heat exchangers because of nuclear plant safety and other reasons. Heat exchangers are classified into two categories of systems, the system for normal operation and the system for emergency operation. The present state and future improvement of heat exchangers are described in view of heat transfer performance, material selection, structural design, vibration, and so on. When noncondensing gas exists in vapour, heat transfer performance deteriorates, so that the heat transfer characteristics should be corrected by the adaption of venting the non condensing gas from the system. Heat transfer tubes should have high corrosion resistance to working fluid as well as high thermal conductivity, strength and economy. From that point of view, 30% cupro-nickel tubes will be replaced with 10% cupro-nickel tubes or titanium tubes though some technical development is necessary. These heat exchangers are now designed according to the MITI criteria for the technology concerning nuclear and thermal power generation, ASME Boiler and Pressure Vessel Code Sec. III and some other criteria. Most of heat transfer tube failures are caused from the tube vibration induced by working fluid flow, so that the vibration test and analysis were performed on U-tube elements. Some correction was obtained for design and fabrication techniques. (Iwase, T.)

An overview of heat exchanger technology in the Canadian nuclear program

International Nuclear Information System (INIS)

Carlucci, L.N.; Dalrymple, D.G.; Ko, P.L.; Pathania, R.; Pettigrew, M.I.; Scott, D.A.

1981-06-01

This paper provides an overview of the Canadian approach to the reliability and serviceability of heat exchange equipment used in nuclear power stations and heavy water plants. Current work in vibration and fretting predictions, thermal-hydraulic analyses, and corrosion research is described. Procedures developed for in-service inspection, in situ tube replacment and chemical cleaning of corrosion products are also outlined

Birth of rats following nuclear exchange at the 2-cell stage.

Science.gov (United States)

Roh, Sangho; Guo, Jitong; Malakooti, Nakisa; Morrison, John R; Trounson, Alan O; Du, Zhong Tao

2003-11-01

We report full-term development of nuclear transfer embryos following nuclear exchange at the 2-cell stage. Nuclei from 2-cell rat embryos were transferred into enucleated 2-cell embryos and developed to term after transfer to recipients (NT2). Pronuclear exchange in zygotes was used for comparison (NT1). Zygotes and 2-cell embryos were harvested from 4-week-old female Sprague-Dawley rats. Nuclear transfer was performed by transferring the pronuclei or karyoplasts into the perivitelline space of recipient embryos followed by electrofusion to reconstruct embryos. Fused couplets were cultured for 4 or 24 h before being transferred into day 1 pseudopregnant recipients (Hooded Wistar) at the 1- or 2-cell stage. In vitro culture was also carried out to check the developmental competence of the embryos. In vitro development to the blastocyst stage was not significantly different between the two groups (NT1, 34.3%; NT2, 45.0%). Two of three recipients from NT1 and two of five recipients from NT2 became pregnant. Six pups (3 from NT1, 3 from NT2) were delivered from the four foster mothers. Three female pups survived; 2 from NT1 and 1 from NT2. At 2 months of age these pups appeared healthy, and were mated with Sprague-Dawley males. One rat derived from NT1 delivered 15 pups (5 males, 10 females) as did the rat from NT2 (7 males, 8 females). Our results show that by using karyoplasts from 2-cell stage embryos as nuclear donors and reconstructing them with enucleated 2-cell embryos, healthy rats can be produced.

Nuclear strategy: India's march towards credible deterrence

International Nuclear Information System (INIS)

Sethi, Manpreet

2009-01-01

May 1998 was a momentous event in India's life. At one level, the five nuclear tests marked the culmination of the long debate on India's nuclear status. At another level, they initiated the country's journey towards credible nuclear deterrence. In the eleventh year of its existence as a state with nuclear weapons, India is engaged in a range of activities to meaningfully integrate the nuclear weapon into its national security strategy. The US and the USSR, at the same stage of their lives were engaged in pretty much a similar exercise. However, unlike the superpowers, for whom the immense destructive potential of the atomic weapon and its implications for inter-state relations suddenly burst on the scene and sent them scrambling to craft strategies that could fit the new reality, India's acquisition of nuclear weapons capability, though dictated by circumstances, came with a basic understanding of the ground rules of the game of nuclear deterrence. In fact, it may be recalled that soon after the tests, there was a spate of books and studies on India's nuclear strategy. A draft nuclear doctrine was made public just fifteen months after the tests and operational issues were beginning to be grappled with

Microscopic nuclear structure calculations with modern meson-exchange potentials

International Nuclear Information System (INIS)

Hjort-Jensen, M.; Osnes, E.; Muether, H.; Schmid, K.W.; Kuo, T.T.S.

1990-07-01

The report presents the results of microscopic nuclear shell-model calculations using three different nucleon-nucleon potentials. These are the phenomenological Reid-Soft-Core potential and the meson-exchange potentials of the Paris and the Bonn groups. It is found that the Bonn potential yields sd-shell matrix elements which are more attractive than those obtained with the Reid or the Paris potentials. The harmonic-oscillator matrix elements of the Bonn potential are also in better agreement with the empirically derived matrix elements of Wildenthal. The implications are discussed. 27 refs., 4 figs., 1 tab

Potential Fuel Loadings, Fire Ignitions, and Smoke Emissions from Nuclear Bursts in Megacities

Science.gov (United States)

Turco, R. P.; Toon, O. B.; Robock, A.; Bardeen, C.; Oman, L.; Stenchikov, G. L.

2006-12-01

We consider the effects of "small" nuclear detonations in modern "megacities," focusing on the possible extent of fire ignitions, and the properties of corresponding smoke emissions. Explosive devices in the multi-kiloton yield range are being produced by a growing number of nuclear states (Toon et al., 2006), and such weapons may eventually fall into the hands of terrorists. The numbers of nuclear weapons that might be used in a regional conflict, and their potential impacts on population and infrastructure, are discussed elsewhere. Here, we estimate the smoke emissions that could lead to widespread environmental effects, including large-scale climate anomalies. We find that low-yield weapons, which emerging nuclear states have been stockpiling, and which are likely to be targeted against cities in a regional war, can generate up to 100 times as much smoke per kiloton of yield as the high-yield weapons once associated with a superpower nuclear exchange. The fuel loadings in modern cities are estimated using a variety of data, including extrapolations from earlier detailed studies. The probability of ignition and combustion of fuels, smoke emission factors and radiative properties, and prompt scavenging and dispersion of the smoke are summarized. We conclude that a small regional nuclear war might generate up to 5 teragrams of highly absorbing particles in urban firestorms, and that this smoke could initially be injected into the middle and upper troposphere. These results are used to develop smoke emission scenarios for a climate impact analysis reported by Oman et al. (2006). Uncertainties in the present smoke estimates are outlined. Oman, L., A. Robock, G. L. Stenchikov, O. B. Toon, C. Bardeen and R. P. Turco, "Climatic consequences of regional nuclear conflicts," AGU, Fall 2006. Toon, O. B., R. P. Turco, A. Robock, C. Bardeen, L. Oman and G. L. Stenchikov, "Consequences of regional scale nuclear conflicts and acts of individual nuclear terrorism," AGU, Fall

A nuclear magnetic relaxation study of hydrogen exchange and water dynamics in aqueous systems

International Nuclear Information System (INIS)

Lankhorst, D.

1983-01-01

In this thesis exchange of water protons in solutions of some weak electrolytes and polyelectrolytes is studied. Also the dynamical behaviour of water molecules in pure water is investigated. For these purposes nuclear magnetic resonance relaxation measurements, in solutions of oxygen-17 enriched water, are interpreted. The exchange rate of the water protons is derived from the contribution of 1 H- 17 O scalar coupling to the proton transverse relaxation rate. This rate is measured by the Carr-Purcell technique. (Auth.)

Promotion of international nuclear cooperation: Need, problems and prospects

International Nuclear Information System (INIS)

Khan, M.A.

1985-01-01

In this panel discussing nonproliferation and international cooperation, the point of view of developing countries, both signatories and nonsignatories to the NPT, is presented. The slow-down in the growth of nuclear trade and industry has adversely affected the economy of energy deficient developing countries, depriving them of the benefits of atomic energy in agriculture and health as well as in power sector. Among 26 countries using nuclear energy for electricity generation, there are just half a dozen developing countries, and their share in the installed nuclear power capacity in the world is only 2 %. Besides the overall slow-down of global economy, the inflexible framework of treaties and quidelines is an important factor of the slow-down. The gradual erosion of mutual confidence between supplier states and recipients has arisen. The greatest threat to world peace is the growing nuclear arsenals of superpowers rather than nuclear proliferation. The role of the IAEA, the setting up of the Committee on Assurance of Supplies, the economy of developing countries and others are discussed. (Kako, I.)

Development of a new generation of ion exchange resin for nuclear and fossil power plant

International Nuclear Information System (INIS)

Tsuzuki, Shintaro; Tagawa, Hidemi; Yamashita, Futoshi; Okamoto, Ryutaro

2008-01-01

It is required to maintain water quality supplied to steam generator to the water designed based on its water chemistry in order to keep the sound operation of nuclear power plants or fossil power plants. Condensate Polishing Plant (CPP) is installed for removing ions in the water which uses a mixed bed of cation exchange resin and anion exchange resin. We have developed new generation of CPP resin. The product is a unique combination of super high exchange capacity cation exchange resin and high fouling resistant anion exchange resin. The CPP resin has been used in many power plants. Amberjet 1006 was developed as a cation exchange resin with high oxidative stability, high operational capacity and New IRA900CP was developed as an anion exchange resin with high fouling resistant to leachables released out of cation exchange resin by oxidative degradation over the service period. The novel CPP resin was first used in 2000 and has now been used in many power plants in Japan. The CPP resin has been giving excellent quality of water. (author)

Experimental simulation study on hydraulic behavior of the main heat exchanger of Daqing 200 MW nuclear heating reactor

International Nuclear Information System (INIS)

Jiang Shengyao; Zhang Youjie; Jia Haijun; Bo Jinhai; Hong Liuming; Bo Hanliang; Liu Zhiyong

1997-07-01

The hydraulic behavior of the main heat exchanger of Daqing 200 MW nuclear heating reactor is studied through a 1:2.33 test model. The design and other feature of the test model is described. The experimental results show that the flow resistance coefficient of the heat exchanger becomes self-simulation when Reynolds number is greater than 5000. The value of flow resistance coefficient at self-simulation condition and the distribution of pressure drop in the heat exchanger are given through experiment. The option design to reduce flow resistance is proposed. The designed and experimental value for the flow resistance coefficient are in good agreement. The variation of system parameters during flow excursion was described. The experimental results are of great significant for the final design of the main heat exchanger of Daqing 200 MW nuclear heating reactor. (2 refs., 5 figs., 1 tab.)

Immobilization in cement of ion exchange resins from Spanish nuclear reactors

International Nuclear Information System (INIS)

Huebra, A.G. de la; Murillo, R.; Ortiz, S.J.

1990-01-01

Ion exchange materials used at nuclear power plants can be immobilized in cements less expensive than polymer matrices. Cement solidification of spent ion exchange resins shows swelling and cracking troubles (during setting time, or of storage). The objective of this study was to select the types of cement that produce the best quality on immobilization of three kinds of resins and to set up cement formulations containing the maximum possible loading of resin. Four cements were selected to carried out the study. After a study of hydration-dehydration phenomena of ion exchange resins, a systematic work has been carried out on immobilization. Tests were performed to study compressive strength and underwater stability by changing water/cement ratio and resin/cement ratio. Mixtures made with water, cement and resin only were loaded with 10% by weight dry resin. Mixtures with higher loadings show poor workability. Tests were carried out by adding organic plasticizers and silica products to improve waste loading. Plasticizers reduced water demand and silica products permit the use of more water. Leaching tests have been performed at 40 O C. In conclusion Blast Furnace Slag is the best cement for immobilization of ion exchange resin both bead and powdered form for mechanical strength, stability and leaching

Specification of steam generator, condenser and regenerative heat exchanger materials for nuclear applications

International Nuclear Information System (INIS)

Jovasevic, J.V.; Stefanovic, V.M.; Spasic, Z.LJ.

1977-01-01

The basic standards specifications of materials for nuclear applications are selected. Seamless Ni-Cr-Fe alloy Tubes (Inconel-600) for steam generators, condensers and other heat exchangers can be employed instead of austenitic stainless steal or copper alloys tubes; supplementary requirements for these materials are given. Specifications of Ni-Cr-Fe alloy plate, sheet and strip for steam generator lower sub-assembly, U-bend seamless copper-alloy tubes for heat exchanger and condensers are also presented. At the end, steam generator channel head material is proposed in the specification for carbon-steel castings suitable for welding

Heat exchanger optimization of a closed Brayton cycle for nuclear space propulsion

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, Guilherme B.; Guimaraes, Lamartine N.F.; Braz Filho, Francisco A., E-mail: gbribeiro@ieav.cta.br, E-mail: guimarae@ieav.cta.br, E-mail: braz@ieav.cta.br [Instituto de Estudos Avancados (IEAV), Sao Jose dos Campos, SP (Brazil). Divisao de Energia Nuclear

2015-07-01

Nuclear power systems turned to space electric propulsion differs strongly from usual ground-based power systems regarding the importance of overall size and weight. For propulsion power systems, weight and efficiency are essential drivers that should be managed during conception phase. Considering that, this paper aims the development of a thermal model of a closed Brayton cycle that applies the thermal conductance of heat exchangers in order to predict the energy conversion performance. The centrifugal-flow turbine and compressor characterization were achieved using algebraic equations from literature data. The binary mixture of He-Xe with molecular weight of 40 g/mole is applied and the impact of heat exchanger optimization in thermodynamic irreversibilities is evaluated in this paper. (author)

Heat exchanger optimization of a closed Brayton cycle for nuclear space propulsion

International Nuclear Information System (INIS)

Ribeiro, Guilherme B.; Guimaraes, Lamartine N.F.; Braz Filho, Francisco A.

2015-01-01

Nuclear power systems turned to space electric propulsion differs strongly from usual ground-based power systems regarding the importance of overall size and weight. For propulsion power systems, weight and efficiency are essential drivers that should be managed during conception phase. Considering that, this paper aims the development of a thermal model of a closed Brayton cycle that applies the thermal conductance of heat exchangers in order to predict the energy conversion performance. The centrifugal-flow turbine and compressor characterization were achieved using algebraic equations from literature data. The binary mixture of He-Xe with molecular weight of 40 g/mole is applied and the impact of heat exchanger optimization in thermodynamic irreversibilities is evaluated in this paper. (author)

Nuclear proliferation: prospects, problems, and proposals

International Nuclear Information System (INIS)

Anon.

1977-01-01

This issue of the ANNALS addresses itself to three aspects of nuclear proliferation: the prospect that new nuclear powers will come on the scene, the problems that their arrival may create, and ways of coping with those problems. In an introductory paper, ''Quo Vadimus,'' Joseph I. Coffey investigates the pros and cons of proliferation, concluding that it is not a question of whether there will be nuclear proliferation, but in what countries. Part I, Where We Are, contains five papers preceded by introductory comments by Joseph I. Coffey. The papers and their authors are: Why States Go--and Don't Go--Nuclear, William Epstein; How States Can ''Go Nuclear,'' Frank C. Barnaby; What Happens If. . .Terrorists, Revolutionaries, and Nuclear Weapons, David Kreiger; Safeguards Against Diversion of Nuclear Material: An Overview, Ryukichi Imai; and Reducing the Incentives to Proliferation, George H. Quester. Part II, And Where We May Go, again includes some introductory remarks by Joseph I. Coffey. The seven succeeding papers are: Nth Powers of the Future, Ashok Kapur; Nuclear Proliferation and World Politics, Lewis A. Dunn; Arms Control in a Nuclear Armed World, Colin Gray; The United Nations, the Superpowers, and Proliferation, Abraham Bargman; Proliferation and the Future: Destruction or Transformation, Frederick C. Thayer; Decision Making in a Nuclear Armed World, Michael Brenner; and The United States in a World of Nuclear Powers, Michael Nacht. This special report is concluded with a glossary

Preliminary design analysis of hot gas ducts and a intermediate heat exchanger for the nuclear hydrogen reactor

International Nuclear Information System (INIS)

Song, K. N.; Kim, Y. W.

2008-01-01

Korea Atomic Energy Research Institute (KAERI) is in the process of carrying out a nuclear hydrogen system by considering the indirect cycle gas cooled reactors that produce heat at temperatures in the order of 950 .deg. C. Primary and secondary hot gas ducts with coaxial double tubes and are key components connecting a reactor pressure vessel and a intermediate heat exchanger for the nuclear hydrogen system. In this study, preliminary design analyses on the hot gas ducts and the intermediate heat exchanger were carried out. These preliminary design activities include a preliminary design on the geometric dimensions, a preliminary strength evaluation, thermal sizing, and an appropriate material selection

Two-pion exchange contributions to nuclear charge asymmetry

International Nuclear Information System (INIS)

Coon, S.A.; Niskanen, J.A.

1995-01-01

An explicit 2π exchange (TPE) potential based on non-relativistic πNN and πΔN vertices with the baryon mass differences taken into account in the vertices is extended to the study of mirror nuclear systems. For the latter study, one must also include baryon mass differences in the intermediate state energy denominators. The TPE potential includes box and crossed box diagrams with two nucleons and those with one nucleon and one Δ. Nuclear charge asymmetry is characterized, in part, by a positive value for the difference Δa = |a nn | - |a pp | ∼ O(1 fm) and a positive value for the 3 H - 3 He binding energy difference ΔE ∼ O(100 keV). The charge asymmetry from baryon mass differences in the vertices is small on this scale and in the wrong direction compared to the empirical values. The contribution from baryon mass differences in the intermediate state energy denominators is positive and is of the order of the empirical scales, in contrast to the previous estimate of Δa ∼ +0.3 fm obtained from an SU(2) symmetric covariant field theoretical potential. This discrepancy between models of TPE is being investigated

Nuclear spin polarized H and D by means of spin-exchange optical pumping

Science.gov (United States)

Stenger, Jörn; Grosshauser, Carsten; Kilian, Wolfgang; Nagengast, Wolfgang; Ranzenberger, Bernd; Rith, Klaus; Schmidt, Frank

1998-01-01

Optically pumped spin-exchange sources for polarized hydrogen and deuterium atoms have been demonstrated to yield high atomic flow and high electron spin polarization. For maximum nuclear polarization the source has to be operated in spin temperature equilibrium, which has already been demonstrated for hydrogen. In spin temperature equilibrium the nuclear spin polarization PI equals the electron spin polarization PS for hydrogen and is even larger than PS for deuterium. We discuss the general properties of spin temperature equilibrium for a sample of deuterium atoms. One result are the equations PI=4PS/(3+PS2) and Pzz=PSṡPI, where Pzz is the nuclear tensor polarization. Furthermore we demonstrate that the deuterium atoms from our source are in spin temperature equilibrium within the experimental accuracy.

Cement solidification of spent ion exchange resins produced by the nuclear industry

International Nuclear Information System (INIS)

Jaouen, C.; Vigreux, B.

1988-01-01

Cement solidification technology has been applied to spent ion exchange resins for many years in countries throughout the world (at reactors, research centers and spent fuel reprocessing plants). Changing specifications for storage of radioactive waste have, however, confronted the operators of such facilities with a number of problems. Problems related both to the cement solidification process (water/cement/resin interactions and chemical interactions) and to its utilization (mixing, process control, variable feed composition, etc.) have often led waste producers to prefer other, polymer-based processes, which are very expensive and virtually incompatible with water. This paper discusses research on cement solidification of ion exchange resins since 1983 and the development of application technologies adapted to nuclear service conditions and stringent finished product quality requirements

Two-dimensional exchange and nutation exchange nuclear quadrupole resonance spectroscopy

International Nuclear Information System (INIS)

Mackowiak, M.; Sinyavsky, N.; Velikite, N.; Nikolaev, D.

2002-01-01

A theoretical treatment of the 2D exchange NQR pulse sequence is presented and applied to a quantitative study of exchange processes in molecular crystals. It takes into account the off-resonance irradiation, which critically influences the spin dynamics. The response to the three-pulse sequence of a system of spins I=3/2 in zero applied field, experiencing electric quadrupole couplings, is analysed. The mixing dynamics by exchange and the expected cross-peak intensities as a function of the frequency offset have been derived. The theory is illustrated by a study of the optimization procedure, which is of crucial importance for the detection of the cross- and diagonal-peaks in a 2D-exchange spectrum. The systems investigated are hexachloroethane and tetrachloroethylene. They show threefold and twofold reorientational jumps about the carbon-carbon axis, respectively. A new method of direct determination of rotational angles based on two-dimensional nutation exchange NQR spectroscopy is proposed. The method involves the detection of exchange processes through NQR nutation spectra recorded after the mixing interval. The response of a system of spins I=3/2 to the three-pulse sequence with increasing pulse widths is analyzed. It is shown that the 2D-nutation exchange NQR spectrum exhibits characteristic ridges, which manifest the motional mechanism in a model-independent fashion. The angles through which the molecule rotates can be read directly from elliptical ridges in the 2D spectrum, which are also sensitive to the asymmetry parameter of the electric field gradient tensor. (orig.)

Exchange of information between nuclear safety authorities: Policy of the French regulator

International Nuclear Information System (INIS)

Asty, Michel

2000-01-01

Full text: The decree setting up the Nuclear Safety Authority in 1973 entrusted it with international assignments whose objectives are still valid: - develop exchanges of information with foreign counterparts on regulatory systems and practices, on problems encountered in the nuclear safety field and on provisions made, with a view to enhancing its approach, and - becoming better acquainted with the actual operating practice of these Safety Authorities from which lessons could be learned for its own working procedures; - improving its position in the technical discussions with the French operators, since its arguments would be strengthened by practical knowledge of conditions abroad; - make known and explain the French approach and practices in the nuclear safety field and provide information on measures taken to deal with the problems encountered. This approach has several objectives: - promote the circulation of information on French positions on certain issues, such as very low level waste, for instance; - assist some countries wishing to create or modify their Nuclear Safety Authority, such as countries of the former USSR, the Central and Eastern European countries, and emerging countries on other continents; - help, when requested, foreign Safety Authorities required to issue permits for nuclear equipment of French origin; - provide the countries concerned with all relevant information on French nuclear installations located near their frontiers. Examples are given on the way the French Nuclear Safety Authority implements these objectives. (author)

Exchange of dose data within nuclear activities in Finland and Sweden

International Nuclear Information System (INIS)

Vilkamo, O.; Malmqvist, L.

1988-01-01

In the Nordic countries, Denmark, Finland, Iceland, Norway and Sweden, only Sweden and Finland have introduced nuclear power into energy production. The first still operating nuclear power plant was commissioned in Sweden in 1972 and in Finland in 1977. It was soon noticed that there was a growing tendency that small groups of workers used to move at short notice between Finland and Sweden to work in the nuclear power plants in both countries during maintenance periods. In 1983, the regulatory authorities for radiation protection, National Institute of Radiation Protection in Sweden and Finnish Centre for Radiation and Nuclear Safety in Finland, surveyed the radiation exposure to those workers. The authorities have brought about an arrangement by means of which the central dose data bases in the other country since 1984 have been able to record without delay the radiation doses received by her own citizens in the nuclear power plants of the neighbouring country. In addition, the authorities have confirmed the procedures of controlling dose data on workers from the neighbouring country, before those workers start working in a nuclear power plant regulated by the national authorities in question. The paper describes the starting point of the activity, the established practice and the experience achieved. Until now, the practical experiences are positive. The total radiation exposure to the workers in the Swedish and Finnish nuclear power plants has been relatively low at each plant site. Thus, the main objective in the exchange of dose data, is to achieve a good radiation protection control

Static and Covariant Meson-Exchange Interactions in Nuclear Matter

International Nuclear Information System (INIS)

Carlson, B.V.; Hirata, D.

2011-01-01

The Dirac version of static meson exchange interactions provides a good description of low-energy NN scattering as well as very reasonable saturation properties in Dirac-Brueckner calculations of nuclear matter. We include retardation terms to make these interactions covariant and readjust the coupling constants so as to maintain a reasonable description of NN scattering. In this case, we find the Dirac-Brueckner approximation to nuclear matter to be extremely overbound. The Bonn meson-exchange interactions provide a good fit to low-energy nucleon-nucleon scattering and the deuteron binding energy using a static interaction and the Thompson form of the reduced two-nucleon interaction. We have readjusted the coupling constants of the these interactions to obtain almost equivalent fits to the scattering data and deuteron binding energy with a static interaction and the Blankenbecler-Sugar form of the reduced two-nucleon propagator and using both forms of the propagator with a covariant interaction. Dirac-Brueckner calculations using the static interactions furnish saturation properties similar to those found for the Bonn interactions. The covariant interactions, on the contrary, yield extreme overbinding and do not show signs of saturation before our calculations diverge. One of the advantages claimed for Dirac mean field calculations over nonrelativistic ones has been the fact that they yield reasonable saturation properties without the necessity of a three-body interaction. This is usually credited to the three-body effects introduced by virtual scattering through the Dirac sea states. These are included, in part, through the Dirac form of the self-energy in our calculations. However, we have explicitly excluded their contribution to the Brueckner scattering kernel. Dirac-Brueckner calculations in which both the positive and negative energy states are included in the scattering kernel result in less binding than those that include only the positive-energy ones

Inorganic ion exchangers for nuclear waste remediation

Energy Technology Data Exchange (ETDEWEB)

Clearfield, A.; Bortun, A.; Bortun, L.; Behrens, E. [Texas A& M Univ., College Station, TX (United States)

1997-10-01

The objective of this work is to provide a broad spectrum of inorganic ion exchangers that can be used for a range of applications and separations involving remediation of groundwater and tank wastes. The authors intend to scale-up the most promising exchangers, through partnership with AlliedSignal Inc., to provide samples for testing at various DOE sites. While much of the focus is on exchangers for removal of Cs{sup +} and Sr{sup 2+} from highly alkaline tank wastes, especially at Hanford, the authors have also synthesized exchangers for acid wastes, alkaline wastes, groundwater, and mercury, cobalt, and chromium removal. These exchangers are now available for use at DOE sites. Many of the ion exchangers described here are new, and others are improved versions of previously known exchangers. They are generally one of three types: (1) layered compounds, (2) framework or tunnel compounds, and (3) amorphous exchangers in which a gel exchanger is used to bind a fine powder into a bead for column use. Most of these exchangers can be regenerated and used again.

Collaborative ReTek exchange - An innovative solution to the skills and resource shortage in the nuclear industry - 16396

International Nuclear Information System (INIS)

Parr, Corhyn

2009-01-01

A Different Approach to the Skills and Resource Shortage The Nuclear Industry has for many years been concerned about a skills and resource shortage. This has been due to a poor perception of the industry by those on the outside, highly competitive industries vying for the same resource pool, a steep retirement curve for highly qualified staff and a lack of graduates entering industry. Here in the UK the creation of the National Skill Academy for Nuclear (NSAN) has put in place a framework to record skills and look to accredit the training providers in the nuclear industry to ensure that the correct skills for the future are available. This has gone some way to solving the skills problem and developing a well recognised accredited system but what about resource - where are the additional qualified resources going to be found? Part of the Solution - A Resource Exchange. How do we solve the skills shortage? We come together as an industry and share the available resource through a collaborative resource exchange. It has been done before in the IT industry when rates for specialists hit Pounds 1500 per day and recruitment agencies were charging extortionate fees for providing temporary resource. ReTek Consulting have developed the ReTek Resource Exchange to provide a neutral collaborative platform across the supply chain; from large scale infrastructure companies and joint venture platforms through to small companies and independent consultants. Using the ReTek Exchange permanent staff are made available to work for others during periods of under-utilisation. Links with similar highly regulated industries enable further management of peaks and troughs and a growth in experienced nuclear professionals through focused training and development. The Benefits of the ReTek Exchange are: - Increased utilisation of your current workforce. - Shared cost of permanent staff. - Speedy access to staff available in your region. - Reduced need for contract or agency staff. - Access

Germany-US Nuclear Theory Exchange Program for QCD Studies of Hadrons & Nuclei 'GAUSTEQ'

Energy Technology Data Exchange (ETDEWEB)

Dudek, Jozef [Old Dominion Univ., Norfolk, VA (United States); Melnitchouk, Wally [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

2016-03-07

GAUSTEQ was a Germany-U.S. exchange program in nuclear theory whose purpose was to focus research efforts on QCD studies of hadrons and nuclei, centered around the current and future research programs of Jefferson Lab and the Gesellschaft fur Schwerionenforschung (GSI) in Germany. GAUSTEQ provided travel support for theoretical physicists at US institutions conducting collaborative research with physicists in Germany. GSI (with its Darmstadt and Helmholtz Institute Mainz braches) served as the German “hub” for visits of U.S. physicists, while Jefferson Lab served as the corresponding “hub” for visits of German physicists visiting U.S. institutions through the reciprocal GUSTEHP (German-US Theory Exchange in Hadron Physics) program. GAUSTEQ was funded by the Office of Nuclear Physics of the U.S. Department of Energy, under Contract No.DE-SC0006758 and officially managed through Old Dominion University in Norfolk, Virginia. The program ran between 2011 and 2015.

Nuclear safety inspection in treatment process for SG heat exchange tubes deficiency of unit 1, TNPS

International Nuclear Information System (INIS)

Zhang Chunming; Song Chenxiu; Zhao Pengyu; Hou Wei

2006-01-01

This paper describes treatment process for SG heat exchange tubes deficiency of Unit 1, TNPS, nuclear safety inspection of Northern Regional Office during treatment process for deficiency and further inspection after deficiency had been treated. (authors)

Chiral approach to nuclear matter: Role of two-pion exchange with virtual delta-isobar excitation

OpenAIRE

Fritsch, S.; Kaiser, N.; Weise, W.

2004-01-01

We extend a recent three-loop calculation of nuclear matter in chiral perturbation theory by including the effects from two-pion exchange with single and double virtual $\\Delta(1232)$-isobar excitation. Regularization dependent short-range contributions from pion-loops are encoded in a few NN-contact coupling constants. The empirical saturation point of isospin-symmetric nuclear matter, $\\bar E_0 = -16 $MeV, $\\rho_0 = 0.16 $fm$^{-3}$, can be well reproduced by adjusting the strength of a two-...

The role of congress in future disposal of fissile materials from dismantled nuclear weapons

International Nuclear Information System (INIS)

Donnelly, W.H.; Davis, Z.S.

1991-01-01

Assuming the Soviet Union remains intact as a major power and the superpowers do not retrogress to a new Cold War era, it is likely that the United States and the Soviet Union will eventually agree to deep cuts in their nuclear arsenals. Future arms control agreements may be coupled with companion agreements to stop production of fissile materials for nuclear weapons, to dismantle the warheads of the nuclear weapons, and to dispose of their fissile materials to prevent reuse in new warheads. Such agreements would be negotiated by the U.S. executive branch but probably would require ratification, funding, and enabling legislation from the U.S. Congress if they are to succeed. There follows a brief review of the ideas for disposal of fissile materials from dismantled nuclear warheads and the potential role and influence of the Congress in the negotiation, ratification, and implementation of U.S.-Soviet agreements for such disposal

Germany-US Nuclear Theory Exchange Program for QCD Studies of Hadrons & Nuclei 'GAUSTEQ'

International Nuclear Information System (INIS)

Dudek, Jozef; Melnitchouk, Wally

2016-01-01

GAUSTEQ was a Germany-U.S. exchange program in nuclear theory whose purpose was to focus research efforts on QCD studies of hadrons and nuclei, centered around the current and future research programs of Jefferson Lab and the Gesellschaft fur Schwerionenforschung (GSI) in Germany. GAUSTEQ provided travel support for theoretical physicists at US institutions conducting collaborative research with physicists in Germany. GSI (with its Darmstadt and Helmholtz Institute Mainz braches) served as the German ''hub'' for visits of U.S. physicists, while Jefferson Lab served as the corresponding ''hub'' for visits of German physicists visiting U.S. institutions through the reciprocal GUSTEHP (German-US Theory Exchange in Hadron Physics) program. GAUSTEQ was funded by the Office of Nuclear Physics of the U.S. Department of Energy, under Contract No.DE-SC0006758 and officially managed through Old Dominion University in Norfolk, Virginia. The program ran between 2011 and 2015.

Heat exchanger

International Nuclear Information System (INIS)

Dostatni, A.W.; Dostatni, Michel.

1976-01-01

In the main patent, a description was given of a heat exchanger with an exchange surface in preformed sheet metal designed for the high pressure and temperature service particularly encountered in nuclear pressurized water reactors and which is characterised by the fact that it is composed of at least one exchanger bundle sealed in a containment, the said bundle or bundles being composed of numerous juxtaposed individual compartments whose exchange faces are built of preformed sheet metal. The present addendun certificate concerns shapes of bundles and their positioning methods in the exchanger containment enabling its compactness to be increased [fr

Chiral approach to nuclear matter: role of two-pion exchange with virtual delta-isobar excitation

Science.gov (United States)

Fritsch, virtual delta-isobar excitation S.; Kaiser, N.; Weise, W.

2005-04-01

We extend a recent three-loop calculation of nuclear matter by including the effects from two-pion exchange with single and double virtual Δ(1232)-isobar excitation. Regularization dependent short-range contributions from pion-loops are encoded in a few NN-contact coupling constants. The empirical saturation point of isospin-symmetric nuclear matter, E=-16 MeV, ρ=0.16 fm, can be well reproduced by adjusting the strength of a two-body term linear in density (and tuning an emerging three-body term quadratic in density). The nuclear matter compressibility comes out as K=304 MeV. The real single-particle potential U(p,k) is substantially improved by the inclusion of the chiral πNΔ-dynamics: it grows now monotonically with the nucleon momentum p. The effective nucleon mass at the Fermi surface takes on a realistic value of M(k)=0.88M. As a consequence of these features, the critical temperature of the liquid-gas phase transition gets lowered to the value T≃15 MeV. In this work we continue the complex-valued single-particle potential U(p,k)+iW(p,k) into the region above the Fermi surface p>k. The effects of 2 π-exchange with virtual Δ-excitation on the nuclear energy density functional are also investigated. The effective nucleon mass associated with the kinetic energy density is M(ρ)=0.64M. Furthermore, we find that the isospin properties of nuclear matter get significantly improved by including the chiral πNΔ-dynamics. Instead of bending downward above ρ as in previous calculations, the energy per particle of pure neutron matter E(k) and the asymmetry energy A(k) now grow monotonically with density. In the density regime ρ=2ρnuclear physics our results agree well with sophisticated many-body calculations and (semi)-empirical values.

Environmental consequences of nuclear war

Energy Technology Data Exchange (ETDEWEB)

Toon, Owen B. [Department of Atmospheric and Oceanic Sciences, Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado (United States); Robock, Alan [Department of Environmental Sciences, Rutgers University, New Brunswick, New Jersey (United States); Turco, Richard P. [Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, Los Angeles, California (United States)

2014-05-09

A regional war involving 100 Hiroshima-sized weapons would pose a worldwide threat due to ozone destruction and climate change. A superpower confrontation with a few thousand weapons would be catastrophic.

Aging management guideline for commercial nuclear power plants - heat exchangers

International Nuclear Information System (INIS)

Booker, S.; Lehnert, D.; Daavettila, N.; Palop, E.

1994-06-01

This Aging Management Guideline (AMG) describes recommended methods for effective detection and mitigation of age-related degradation mechanisms in commercial nuclear power plant heat exchangers important to license renewal. The intent of this AMG is to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR 54. This AMG is presented in a manner that allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein

Aging management guideline for commercial nuclear power plants - heat exchangers

Energy Technology Data Exchange (ETDEWEB)

Booker, S.; Lehnert, D.; Daavettila, N.; Palop, E.

1994-06-01

This Aging Management Guideline (AMG) describes recommended methods for effective detection and mitigation of age-related degradation mechanisms in commercial nuclear power plant heat exchangers important to license renewal. The intent of this AMG is to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR 54. This AMG is presented in a manner that allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

Folding model study of the charge-exchange scattering to the isobaric analog state and implication for the nuclear symmetry energy

International Nuclear Information System (INIS)

Khoa, Dao T.; Thang, Dang Ngoc; Loc, Bui Minh

2014-01-01

The Fermi transition (ΔL = ΔS = 0 and ΔT = 1) between the nuclear isobaric analog states (IAS), induced by the charge-exchange (p, n) or ( 3 He, t) reaction, can be considered as ''elastic'' scattering of proton or 3 He by the isovector term of the optical potential (OP) that flips the projectile isospin. The accurately measured (p, n) or ( 3 He, t) scattering cross section to the IAS can be used, therefore, to probe the isospin dependence of the proton or 3 He optical potential. Within the folding model, the isovector part of the OP is determined exclusively by the neutron-proton difference in the nuclear densities and the isospin dependence of the effective nucleon-nucleon (NN) interaction. Because the isovector coupling explicitly links the isovector part of the proton or 3 He optical potential to the cross section of the charge-exchange (p, n) or ( 3 He, t) scattering to the IAS, the isospin dependence of the effective (in-medium) NN interaction can be well tested in the folding model analysis of these charge-exchange reactions. On the other hand, the same isospin- and density-dependent NN interaction can also be used in a Hartree-Fock calculation of asymmetric nuclear matter, to estimate the nuclear matter energy and its asymmetry part (the nuclear symmetry energy). As a result, the fine-tuning of the isospin dependence of the effective NN interaction against the measured (p, n) or ( 3 He, t) cross sections should allow us to make some realistic prediction of the nuclear symmetry energy and its density dependence. (orig.)

Neutrino nuclear responses for double beta decays and astro neutrinos by charge exchange reactions

Science.gov (United States)

Ejiri, Hiroyasu

2014-09-01

Neutrino nuclear responses are crucial for neutrino studies in nuclei. Charge exchange reactions (CER) are shown to be used to study charged current neutrino nuclear responses associated with double beta decays(DBD)and astro neutrino interactions. CERs to be used are high energy-resolution (He3 ,t) reactions at RCNP, photonuclear reactions via IAR at NewSUBARU and muon capture reactions at MUSIC RCNP and MLF J-PARC. The Gamow Teller (GT) strengths studied by CERs reproduce the observed 2 neutrino DBD matrix elements. The GT and spin dipole (SD) matrix elements are found to be reduced much due to the nucleon spin isospin correlations and the non-nucleonic (delta isobar) nuclear medium effects. Impacts of the reductions on the DBD matrix elements and astro neutrino interactions are discussed.

Research advances in adsorption treatment of cesium and cobalt in waste liquid of nuclear power plants by ion exchange resin

International Nuclear Information System (INIS)

Liu Dan; Wang Xin; Liu Jiean; Zhu Laiye; Chen Bin; Weng Minghui

2014-01-01

Liquid radwaste is unavoidably produced during the operation of nuclear power plants (NPP). With the development of China's nuclear power, much more attention will be paid to the impact of NPP construction on water environment. Radionuclides are the main targets for adsorption treatment of NPP liquid radwaste. Thereinto, cesium and cobalt are typical cationic ones. Currently, ion exchange process is widely used in liquid radwaste treatment system (WLS) of NPP, wherein resin plays a key role. The paper reviewed the research progress on adsorption of cesium and cobalt existed in NPP liquid radwaste using ion exchange resin. (authors)

Nuclear code case development of printed-circuit heat exchangers with thermal and mechanical performance testing

Energy Technology Data Exchange (ETDEWEB)

Aakre, Shaun R. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Mechanical Engineering; Jentz, Ian W. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Mechanical Engineering; Anderson, Mark H. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Mechanical Engineering

2018-03-27

The U.S. Department of Energy has agreed to fund a three-year integrated research project to close technical gaps involved with compact heat exchangers to be used in nuclear applications. This paper introduces the goals of the project, the research institutions, and industrial partners working in collaboration to develop a draft Boiler and Pressure Vessel Code Case for this technology. Heat exchanger testing, as well as non-destructive and destructive evaluation, will be performed by researchers across the country to understand the performance of compact heat exchangers. Testing will be performed using coolants and conditions proposed for Gen IV Reactor designs. Preliminary observations of the mechanical failure mechanisms of the heat exchangers using destructive and non-destructive methods is presented. Unit-cell finite element models assembled to help predict the mechanical behavior of these high-temperature components are discussed as well. Performance testing methodology is laid out in this paper along with preliminary modeling results, an introduction to x-ray and neutron inspection techniques, and results from a recent pressurization test of a printed-circuit heat exchanger. The operational and quality assurance knowledge gained from these models and validation tests will be useful to developers of supercritical CO₂ systems, which commonly employ printed-circuit heat exchangers.

Progress in scale-up of second-generation high-temperature superconductors at SuperPower Inc

Energy Technology Data Exchange (ETDEWEB)

Xie, Y.-Y. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States)]. E-mail: yxie@igc.com; Knoll, A. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Chen, Y. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Li, Y. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Xiong, X. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Qiao, Y. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Hou, P. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Reeves, J. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Salagaj, T. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Lenseth, K. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Civale, L. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Maiorov, B. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Iwasa, Y. [Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Solovyov, V. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Suenaga, M. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Cheggour, N. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Clickner, C. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Ekin, J.W. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Weber, C. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Selvamanickam, V. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States)

2005-10-01

SuperPower is focused on scaling up second-generation (2-G) high-temperature superconductor (HTS) technology to pilot-scale manufacturing. The emphasis of this program is to develop R and D solutions for scale-up issues in pilot-scale operations to lay the foundation for a framework for large-scale manufacturing. Throughput continues to be increased in all process steps including substrate polishing, buffer and HTS deposition. 2-G HTS conductors have been produced in lengths up to 100 m. Process optimization with valuable information provided by several unique process control and quality-control tools has yielded performances of 6000-7000 A m (77 K, 0 T) in 50-100 m lengths using two HTS fabrication processes: metal organic chemical vapor deposition (MOCVD) and pulsed laser deposition (PLD). Major progress has been made towards the development of practical conductor configurations. Modifications to the HTS fabrication process have resulted in enhanced performance in magnetic fields. Industrial slitting and electroplating processes have been successfully adopted to fabricate tapes in width of 4 mm and with copper stabilizer for cable and coil applications. SuperPower's conductor configuration has yielded excellent mechanical properties and overcurrent carrying capability. Over 60 m of such practical conductors with critical current over 100 A/cm-width have been delivered to Sumitomo Electric Industries, Ltd. for prototype cable construction.

Behavioral aspects of negotiations on mutual security

International Nuclear Information System (INIS)

Druckman, D.; Hopmann, P.T.

1989-01-01

This article surveys theory and research about the process of international negotiation. The goal, of this paper is to apply behavioral science research to find ways to negotiate an improved mutual security regime between the nuclear superpowers that would make nuclear war less likely in the years ahead. When President John F. Kennedy presented the first nuclear arms control agreement, the Partial Nuclear Test Ban Treaty, to the U.S. public in 1963 he noted the ancient Chinese proverb: A journey of a thousand miles must begin with a single step. Just as the Partial Nuclear Test Ban Treaty represented for Kennedy the first step on the road to nuclear arms control, so the research reviewed here represents at best the first few steps in a long journey to a better understanding of how to negotiate a regime of mutual security between the nuclear superpowers

Heat Exchanger Tube Inspection of Nuclear Power Plants using IRIS Technique

International Nuclear Information System (INIS)

Yoon, Byung Sik; Yang, Seung Han; Song, Seok Yoon; Kim, Yong Sik; Lee, Hee Jong

2005-01-01

Inspection of heat exchange tubing include steam generator of nuclear power plant mostly performed with eddy current method. Recently, various inspection technique is available such as remote field eddy current, flux leakage and ultrasonic methods. Each of these techniques has its merits and limitations. Electromagnetic techniques are very useful to locate areas of concern but sizing is hard because of the difficult interpretation of an electric signature. On the other hand, ultrasonic methods are very accurate in measuring wall loss damage, and are reliable for detecting cracks. Additionally ultrasound methods is not affected by support plates or tube sheets and variation of electrical conductivity or permeability. Ultrasound data is also easier to analyze since the data displayed is generally the remaining wall thickness. It should be emphasized that ultrasound is an important tool for sizing defects in tubing. In addition, it can be used in situations where eddy current or remote field eddy current is not reliable, or as a flaw assessment tool to supplement the electromagnetic data. The need to develop specialized ultrasonic tools for tubing inspection was necessary considering the limitations of electromagnetic techniques to some common inspection problems. These problems the sizing of wall loss in carbon steel tubes near the tube sheet or support plate, sizing internal erosion damage, and crack detection. This paper will present an IRIS(Internal Rotating Inspection System) ultrasonic tube inspection technique for heat exchanger tubing in nuclear power plant and verify inspection reliability for artificial flaw embedded to condenser tube

Design option of heat exchanger for the next generation nuclear plant - HTR2008-58175

International Nuclear Information System (INIS)

Oh, C. H.; Kim, E. S.

2008-01-01

The Next Generation Nuclear Plant (NGNP), a very High temperature Gas-Cooled Reactor (VHTR) concept, will provide the first demonstration of a closed-loop Brayton cycle at a commercial scale, producing a few hundred megawatts of power in the form of electricity and hydrogen. The power conversion unit (PCU) for the NGNP will take advantage of the significantly higher reactor outlet temperatures of the VHTRs to provide higher efficiencies than can be achieved with the current generation of light water reactors. Besides demonstrating a system design that can be used directly for subsequent commercial deployment, the NGNP will demonstrate key technology elements that can be used in subsequent advanced power conversion systems for other Generation IV reactors. In anticipation of the design, development and procurement of an advanced power conversion system for the NGNP, the system integration of the NGNP and hydrogen plant was initiated to identify the important design and technology options that must be considered in evaluating the performance of the proposed NGNP. As part of the system integration of the VHTRs and the hydrogen production plant, the intermediate heat exchanger is used to transfer the process heat from VHTRs to the hydrogen plant. Therefore, the design and configuration of the intermediate heat exchanger is very important. This paper will include analysis of one stage versus two stage heat exchanger design configurations and simple stress analyses of a printed circuit heat exchanger (PCHE), helical coil heat exchanger, and shell/tube heat exchanger. (authors)

The selection and performance of the natural zeolite clinoptilolite in British Nuclear Fuels' site ion exchange effluent plant, SIXEP

International Nuclear Information System (INIS)

Baxter, S.G.; Berghauser, D.C.

1986-01-01

SIXEP has been conducted by British Nuclear Fuels plc at its Sellafield reprocessing site as part of its committment to reduce radioactive discharges to the Irish Sea. An extensive development program identified the natural ion exchange mineral clinoptilolite, from a particular deposit in California now owned by Tenneco Specialty Minerals, as the most suitable for use in SIXEP to extract caesium and strontium from spent nuclear fuel storage pond water. Close cooperation with the supplier in a Quality Assurance scheme ensured the supply of a fully-characterised, high grade ion exchanger. Since SIXEP commenced treating pond water on 28 May 1985, the plant has performed well, exceeding the design expectation in terms of discharge reduction and availability

Folding model study of the charge-exchange scattering to the isobaric analog state and implication for the nuclear symmetry energy

Energy Technology Data Exchange (ETDEWEB)

Khoa, Dao T.; Thang, Dang Ngoc [VINATOM, Institute for Nuclear Science and Technique, Hanoi (Viet Nam); Loc, Bui Minh [VINATOM, Institute for Nuclear Science and Technique, Hanoi (Viet Nam); University of Pedagogy, Ho Chi Minh City (Viet Nam)

2014-02-15

The Fermi transition (ΔL = ΔS = 0 and ΔT = 1) between the nuclear isobaric analog states (IAS), induced by the charge-exchange (p, n) or ({sup 3}He, t) reaction, can be considered as ''elastic'' scattering of proton or {sup 3}He by the isovector term of the optical potential (OP) that flips the projectile isospin. The accurately measured (p, n) or ({sup 3}He, t) scattering cross section to the IAS can be used, therefore, to probe the isospin dependence of the proton or {sup 3}He optical potential. Within the folding model, the isovector part of the OP is determined exclusively by the neutron-proton difference in the nuclear densities and the isospin dependence of the effective nucleon-nucleon (NN) interaction. Because the isovector coupling explicitly links the isovector part of the proton or {sup 3}He optical potential to the cross section of the charge-exchange (p, n) or ({sup 3}He, t) scattering to the IAS, the isospin dependence of the effective (in-medium) NN interaction can be well tested in the folding model analysis of these charge-exchange reactions. On the other hand, the same isospin- and density-dependent NN interaction can also be used in a Hartree-Fock calculation of asymmetric nuclear matter, to estimate the nuclear matter energy and its asymmetry part (the nuclear symmetry energy). As a result, the fine-tuning of the isospin dependence of the effective NN interaction against the measured (p, n) or ({sup 3}He, t) cross sections should allow us to make some realistic prediction of the nuclear symmetry energy and its density dependence. (orig.)

On the swelling of ion exchange resins used in Swedish nuclear power plants

International Nuclear Information System (INIS)

Nilsson, A.C.; Hoegfeldt, E.; Muhammed, M.

1988-03-01

Ion exchange resins are used in nuclear power plants for purification and decontamination of water. In some of the cases, the spent resins are solidified by drying at elevated temperatures and then molded together with bitumen before final disposal. The objective of the present work is to study the swelling behavior of such resins and describe it with a model that permits calculation of the water uptake into the bituminized resins and the external swelling pressure that might develop by the swelling resins under repository conditions. The experimental part of the study comprises the swelling of ion exchange resins upon their exposure to water vapour before and after thermal treatment under conditions simulating those used in the various solidification processes. Seven different resins were studied in different chemical forms; H + , N + and OH - , So 4 2- for the cation an anion exchangers respectively. For each resin, water uptake, density and volume were measured at different water activities at 25 degrees C. The swelling pressure for all resins studied was calculated. A slight increase in swelling pressure after thermal treatment could be observed, especially for anion exchangers. The apparent molar volume of water in the resin phase has been determined and the swelling free energies of swelling has been calculated from experimental data at 25 degrees C and estimated at 0 degrees C. (authors)

Upright heat exchanger

International Nuclear Information System (INIS)

Martoch, J.; Kugler, V.; Krizek, V.; Strmiska, F.

1988-01-01

The claimed heat exchanger is characteristic by the condensate level being maintained directly in the exchanger while preserving the so-called ''dry'' tube plate. This makes it unnecessary to build another pressure vessel into the circuit. The design of the heat exchanger allows access to both tube plates, which facilitates any repair. Another advantage is the possibility of accelerating the indication of leakage from the space of the second operating medium which is given by opening the drainage pipes of the lower bundle into the collar space and from there through to the indication pipe. The exchanger is especially suitable for deployment in the circuits of nuclear power plants where the second operating medium will be hot water of considerably lower purity than is that of the condensate. A rapid display of leakage can prevent any long-term penetration of this water into the condensate, which would result in worsening water quality in the entire secondary circuit of the nuclear power plant. (J.B.). 1 fig

Terrorism and global security: The nuclear threat

International Nuclear Information System (INIS)

Beres, L.R.

1987-01-01

In the seven years since this book was first published, the threat of nuclear terrorism has increased dramatically. The enormous destructive potential of nuclear technology inevitably raises the specter of the use of nuclear explosives or radioactivity by insurgent groups. The author explores the political bases of terrorism by considering the factors that might foster nuclear terrorism, the forms it could take, and the probable consequences of such acts. New to this edition is the author's examination of the essential distinctions between lawful insurgencies and terrorism, as well as his analysis of the impact of recent U.S. foreign policy. The author explores the United State's all-consuming rivalry with the Soviet Union, arguing that it has created an atmosphere ripe for anti-U.S. terrorism and that the only viable option for the super-powers is cooperation in an effort to control terrorist activities. He also discusses the ''Reagan doctrine,'' which he believes has increased the long-term threat of nuclear terrorism against the U.S. by its continuing support of authoritarian regimes and by its active opposition to Marxist regimes such as those in Nicaragua and Angola. The book concludes by presenting the first coherent strategy for countering nuclear terrorism-embracing both technological and behavioral measures. The proposal includes policies for deterrence and situation management on national and international scales and emphasizes the logic of a major reshaping of world order

Consequences of Regional Scale Nuclear Conflicts and Acts of Individual Nuclear Terrorism

Science.gov (United States)

Toon, O. B.; Turco, R. P.; Robock, A.; Bardeen, C.; Oman, L.; Stenchikov, G. L.

2006-12-01

The number of nuclear warheads in the world has fallen by about a factor of three since its peak in 1986. However, the potential exists for numerous regional nuclear arms races, and for a significant expansion in the number of nuclear weapons states. Eight countries are known to have nuclear weapons, 2 are constructing them, and an additional 32 nations already have the fissile material needed to build weapons if they so desire. Population and economic activity worldwide are congregated to an increasing extent in "megacities", which are ideal targets for nuclear weapons. We find that low yield weapons, which new nuclear powers are likely to construct, can produce 100 times as many fatalities and 100 times as much smoke from fires per kt yield as high-yield weapons, if they are targeted at city centers. A single low-yield nuclear detonation in an urban center could lead to more fatalities, in some cases by orders of magnitude, than have occurred in major historical conflicts. A regional war between the smallest current nuclear states involving 100 15-kt explosions (less than 0.1% of the explosive yield of the current global nuclear arsenal) could produce direct fatalities comparable to all of those worldwide in World War II (WW-II), or to those once estimated for a "counterforce" nuclear war between the superpowers. Portions of megacities attacked with nuclear devices or exposed to fallout of long-lived isotopes, through armed conflict or terrorism, would likely be abandoned indefinitely, with severe national and international implications. Smoke from urban firestorms in a regional war might induce significant climatic and ozone anomalies on global scales. While there are many uncertainties in the issues we discuss here, the major uncertainties are the type and scale of conflict that might occur. Each of these potential hazards deserves careful analysis by governments worldwide advised by a broad section of the world scientific community, as well as widespread

Proceedings of the 1st JAEA/KAERI information exchange meeting on HTGR and nuclear hydrogen technology

International Nuclear Information System (INIS)

Sato, Hiroyuki; Sakaba, Nariaki; Nishihara, Tetsuo; Yan, Xing L.; Hino, Ryutaro

2007-03-01

Japan Atomic Energy Agency (JAEA) has completed an implementation with Korea Atomic Energy Research Institute (KAERI) on HTGR and nuclear hydrogen technology, 'The Implementation of Cooperative Program in the Field of Peaceful Uses of Nuclear Energy between KAERI and JAEA. 'To facilitate efficient technology development on HTGR and nuclear hydrogen by the IS process, an information exchange meeting was held at the Oarai Research and Development Center of JAEA on August 28-30, 2006 under Program 13th of the JAEA/KAERI Implementation, 'Development of HTGR and Nuclear Hydrogen Technology'. JAEA and KAERI mutually showed the status and future plan of the HTTR (High-Temperature Engineering Test Reactor) project in Japan and of the NHDD (Nuclear Hydrogen Development and Demonstration) project in Korea, respectively, and discussed collaboration items. This proceedings summarizes all materials of presented technical discussions on HTGR and hydrogen production technology as well as the meeting briefing including collaboration items. (author)

Explosive plugging of nuclear heat exchangers

International Nuclear Information System (INIS)

Crossland, B.; Bahrani, A.S.; Townsley, W.J.

1977-01-01

Explosive welding is a well established process for cladding one metal on another or for welding tubes to tubeplates or lap welding, etc. Recently, the process has been adapted to plugging of heat exchangers in conventional and nuclear power plant, where it has already been accepted especially in situations where the access is difficult and remote from the site of plugging. The paper describes the explosive plugging techniques developed in the Department of Mechanical and Industrial Engineering of The Queen's University of Belfast for the reheater and superheater of the PFR, and for the reheater of the AGR. For the PFR a point charge system has been used which causes a spherical expansion of the plug, which gives two zones of welding. Initially for the much larger plug required for the AGR it was proposed to use a parallel stand-off welding set-up, but it proved difficult or impossible to avoid a crevice. Consequently, a rim charge set-up has been developed which gives a circular ring expansion of the plug with two zones of welding. Besides the problem of the design of the plug and explosive charge geometry it has also been necessary to consider the distortion of holes adjoining the hole in which a plug is welded. Bunging of adjoining holes in order to reduce the distortion has also been investigated

Qualification of expansion and welding procedures of tube-to-tubesheet joints for heat exchangers in nuclear power plants

International Nuclear Information System (INIS)

Camargo, G.D.M.; Couto, J.G.V.; Castro, L.A.S. de

1986-01-01

Leaking tube to tubesheet joints are among the most frequent defects detected in the operation of tubular heat exchangers. This kind of problem requires a special treatment, in the case of heat exchangers intalled in nuclear power plants, aiming at a minimum of leakages and further repair outages. The criteria used for the pre-qualification of tube-to-tubesheet joints, is described, and the experiences acquired during the tests and fabrication of several components supplied by national manufacturers, are presented. (Author) [pt

Memorandum of understanding between the Federal Minister for the Environment, nature conservation and nuclear safety of the Federal Republic of Germany and the atomic energy control board of Canada on cooperation and exchange of information respecting nuclear safety and radiation

International Nuclear Information System (INIS)

1991-01-01

This Memorandum of Understanding on co-operation and exchange of information respecting nuclear safety and radiation protection covers the period 23 May 1991 to 1 June 1996. The Parties may exchange information on any matter concerning the civil uses of nuclear energy within the other Party's jurisdiction and, in particular information on: nuclear installations, their siting, construction, operation and decommissioning; uranium mining and milling; nuclear fuel production; radioactive waste treatment, storage and disposal; transport of nuclear fuel and radioactive waste; radiation protection; legislation, regulations, standards. All information received and the results of activities carried out under this Memorandum of Understanding will be used exclusively for peaceful purposes [fr

DE PODER NULO A SUPERPODER: O JUDICIÁRIO DE MONTESQUIEU, REVISITADO | FROM NULL TO SUPER-POWER: MONTESQUIEU’S JUDICIARY REVIEWED

Directory of Open Access Journals (Sweden)

Sandro Luís Tomás Ballande Romanelli

2016-08-01

Full Text Available This article discusses the Judiciary within the doctrine of separation of powers, aiming to provide historical and political data that could explain judicial protagonism. This is achieved through book reviews of contemporary political science literature and classic authors from the 18 th century. Therefore, it aims to examine in depth some chapters of Montesquieu’s “Spirit of laws” classic book, expressing how its theory of judicial power was deeply linked with ancient régime’s judicial system, in a context where 18 th century French Judiciary Power was a great source of threat to both political and legislative powers. The paper addresses how the American Constitution bended the original theory, moving from an absolute separation of powers towards a super-powered Judiciary in defence of individual liberties, acting as counterbalance to state assemblies and local political powers. In conclusion, it stands that Judicial Power protagonism doesn’t violate the classic theory of separation of powers.

Application of ion exchange processes for the treatment of radioactive waste and management of spent ion exchangers

International Nuclear Information System (INIS)

2002-01-01

This report describes the ion exchange technologies currently used and under development in nuclear industry, in particular for waste management practices, along with the experience gained in their application and with the subsequent handling, treatment and conditioning of spent ion exchange media for long term storage and/or disposal. The increased role of inorganic ion exchangers for treatment of radioactive liquid waste, both in nuclear power plant operations and in the fuel reprocessing sector, is recognised in this report. The intention of this report is to consolidate the previous publications, document recent developments and describe the state of the art in the application of ion exchange processes for the treatment of radioactive liquid waste and the management of spent ion exchange materials

Nuclear proliferation in the Third World: an analysis of decision making in Indiana and Pakistan

International Nuclear Information System (INIS)

Gdaia, A.M.

1985-01-01

The causes of nuclear proliferation in the Third World are analyzed by examining the motives and forces that went into the nuclear decisions of India and Pakistan. A comprehensive framework is used that consists of five levels of analysis: international, societal, governmental, bureaucratic, and individual factors. The study examines how various potential motives that might impel a nation to acquire nuclear weapons operated through the different levels of analysis. It is concluded that the security motive was the primary determinant in each case as opposed to other motives such as desire for international status or economic considerations. However, security motives were joined by other values and constraints. Regional conflict combined with the lack of a superpower guarantee of security to persuade both countries to pursue nuclear weapons. Such domestic factors as the type of political systems, public opinion, and mass media seemed to play a very limited role in the decisions, although a larger role in India than in Pakistan. Finally, strong individual leadership was a relatively powerful determinant of policy in both countries

International exchange of safety and licensing information

International Nuclear Information System (INIS)

Lafleur, J.D. Jr.; Hauber, R.D.; Chenier, D.M.

1977-01-01

A network of formal and informal bilateral arrangements for the exchange of nuclear safety information is being established by the U.S. Nuclear Regulatory Commission. For developing countries, such arrangements can provide ready access to the extensive, fully documented safety analyses and safety research results that NRC has accumulated. NRC has been receiving foreign visitors at a rate of about 500 per year, largely for discussions of safety and licensing questions related to light water reactors. Exchanges also are taking place on the safety of advanced reactors. A special interest of the NRC is in providing for reciprocal communicaion, at the earliest possible time, of important problems, decisions and other actions on nuclear safety matters. For example, it is essential that a newly-discovered problem in a nuclear reactor be brought immediately to the attention of other governments which are responsible for the safety of similar reactors. Definite progress has been made in the U.S. Freedom of Information Act. Certain exchanges have taken place on this basis. Experience in the establishment and operation of NRC's bilateral exchange arrangements is summarized. A typical exchange with the regulatory authority of country building its first power reactor is described

Essential Specification Elements for Heat Exchanger Replacement

Energy Technology Data Exchange (ETDEWEB)

Bower, L.

2015-07-01

Performance upgrade and equipment degradation are the primary impetuses for a nuclear power plant to engage in the large capital cost project of heat exchanger replacement. Along with attention to these issues, consideration of heat exchanger Codes and Standards, material improvements, thermal redesign, and configuration are essential for developing User’s Design Specifications for successful replacement projects. The User’s Design Specification is the central document in procuring ASME heat exchangers. Properly stated objectives for the heat exchanger replacement are essential for obtaining the materials, configurations and thermal designs best suited for the nuclear power plant. Additionally, the code of construction required and the applied manufacturing standard (TEMA or HEI) affects how the heat exchanger may be designed or configured to meet the replacement goals. Knowledge of how Codes and Standards affect design and configuration details will aid in writing the User’s Design Specification. Joseph Oat Corporation has designed and fabricated many replacement heat exchangers for the nuclear power industry. These heat exchangers have been constructed per ASME Section III to various Code-Years or ASME Section VIII-1 to the current Code-Year also in accordance with TEMA and HEI. These heat exchangers have been a range of like-for-like replacement to complete thermal, material and configuration redesigns. Several examples of these heat exchangers with their Code, Standard and specification implications are presented. (Author.

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.

The (safety-related) heat exchangers aging management guideline for commercial nuclear power plants, and developments since 1994

International Nuclear Information System (INIS)

Clauss, J.M.

1998-01-01

The US Department of Energy (DOE), in cooperation with the Electric Power Research Institute (EPRI) and US nuclear power plant utilities, is preparing a series of aging management guidelines (AMGs) for commodity types of components (e.g., heat exchangers, electrical cable and terminations, pumps). Commodities are included in this series based on their importance to continued nuclear plant operation and license renewal. The AMGs contain a detailed summary of operating history, stressors, aging mechanisms, and various types of maintenance and surveillance practices that can be combined to create an effective aging management program. Each AMG is intended for use by the systems engineers and plant maintenance staff (i.e., an AMG is intended to be a hands-on technical document rather than a licensing document). The heat exchangers AMG, published in June 1994, includes the following information of interest to nondestructive examination (NDE) personnel: aging mechanisms determined to be non-significant for all applications; aging mechanisms determined to be significant for some applications; effective conventional programs for managing aging; and effective unconventional programs for managing aging. Since the AMG on heat exchangers was published four years ago, a brief review has been conducted to identify emerging regulatory issues, if any. The results of this review and lessons learned from the collective set of AMGs are presented

Modeling a Printed Circuit Heat Exchanger with RELAP5-3D for the Next Generation Nuclear Plant

International Nuclear Information System (INIS)

2010-01-01

The main purpose of this report is to design a printed circuit heat exchanger (PCHE) for the Next Generation Nuclear Plant and carry out Loss of Coolant Accident (LOCA) simulation using RELAP5-3D. Helium was chosen as the coolant in the primary and secondary sides of the heat exchanger. The design of PCHE is critical for the LOCA simulations. For purposes of simplicity, a straight channel configuration was assumed. A parallel intermediate heat exchanger configuration was assumed for the RELAP5 model design. The RELAP5 modeling also required the semicircular channels in the heat exchanger to be mapped to rectangular channels. The initial RELAP5 run outputs steady state conditions which were then compared to the heat exchanger performance theory to ensure accurate design is being simulated. An exponential loss of pressure transient was simulated. This LOCA describes a loss of coolant pressure in the primary side over a 20 second time period. The results for the simulation indicate that heat is initially transferred from the primary loop to the secondary loop, but after the loss of pressure occurs, heat transfers from the secondary loop to the primary loop.

Corrosion study of heat exchanger tubes in pressurized water cooled nuclear reactors by conversion electron Moessbauer spectroscopy

International Nuclear Information System (INIS)

Homonnay, Z.; Kuzmann, E.; Varga, K.; Nemeth, Z.; Szabo, A.; Rado, K.; Schunk, J.; Tilky, P.; Patek, G.

2005-01-01

Nuclear energy production tends to return into the focus of interest because of the constantly increasing energy need of the world and the green house effect problems of the strongest competitor oil or gas based power plants. In addition to the construction of new nuclear power plants, lifetime extension of the existing ones is the most cost effective investment in the energy business. However, feasibility and safety issues become very important at this point, and corrosion of the construction materials should be carefully investigated before decision on a potential lifetime extension of a reactor. 57 Fe-Conversion Electron Moessbauer Spectroscopy (CEMS) is a sensitive tool to analyze the phase composition of corrosion products on the surface of stainless steel. The upper ∼300 nm can be investigated due to the penetration range of conversion electrons. The corrosion state of heat exchanger tubes from the four reactor units of the Paks Nuclear Power Plant, Hungary, were analyzed by several methods including CEMS. The primary circuit side of the tubes was studied on selected samples cut out from the heat exchangers during regular maintenance. Cr- and Ni-substituted magnetite, sometimes hematite, amorphous Fe-oxides/oxyhydroxides as well as the signal of bulk austenitic steel of the tubes were detected. The level of Cr- and Ni-substitution in the magnetite phase could be estimated from the Moessbauer spectra. Correlation between earlier decontamination cycles and the corrosion state of the heat exchangers was sought. In combination with other methods, a hybrid structure of the surface oxide layer of several microns was established. It is suggested that previous AP-CITROX decontamination cycles can be responsible for this structure which makes the oxide layer mobile. This mobility may be responsible for unwanted corrosion product transport into the reactor vessel by the primary coolant.

Considerations regarding design of ion exchange columns for applications in heavy water nuclear reactors- a comprehensive review

International Nuclear Information System (INIS)

Joginder Kumar; Nema, M.K.

2000-01-01

In nuclear reactor applications the principal role of the purification system is to maintain a satisfactory chemistry of moderator and coolant which are different at various stages of reactor operations e.g. during reactor start up, for removal of neutron poison from the moderator, the purification flows are much different compared to steady state operation of the reactor. In order to cater to varying requirements regarding purification load, optimisation in connection with ion exchange column design plays an important role and becomes very challenging in Heavy Water Nuclear Reactors mainly due to the fact that heavy water is very very expensive. In this paper a comprehensive review is made for various designs adopted so far regarding IX column in Indian PHWRs of 220 MWe size for normal operations. Design and operating experience regarding large size IX column used for occasional needs during dilute chemical decontamination of 220 MWe PHWRs is also discussed. The experience regarding development testing of the proposed design of ion exchange column for 500 MWe PHWRs is also discussed

International nuclear commerce: structure, trends and proliferation potentials

International Nuclear Information System (INIS)

Lodgaard, S.

1977-01-01

In recent years a surge has taken place in international nuclear commerce and this paper analyses the new patterns that have emerged. Despite uncertainties in nuclear energy forecasting the market is huge. Projections for the industry for the period 1971-1985 estimate a worldwide investment of 250 billion dollars. Following an initial decade of cooperation, 1955-1965, the superpower monopoly has become eroded. The export market for power reactors is analysed and the growth and spread of reprocessing facilities is discussed. It is pointed out that while commercial scale reprocessing requires vast and complex chemical plant, reprocessing small amounts for bomb production may be done relatively simply. Enrichment capabilities are also becoming more generally available. The market is not only expanding, but becoming multipolar and diversified, and the entire fuel cycle is now involved. The cooperation network France - W. Germany - South Africa- Iran is discussed at some length. The role of international safeguards is also treated fairly extensively, leading to a discussion of the motives and paths in the acquisition of nuclear weapons. It is concluded that little is to be gained from the London talks on safeguard measures and commercial restraint and that the root causes of proliferation should be tackled by comprehensive disarmament schemes. (JIW)

Nuclear Reaction Data Centers

International Nuclear Information System (INIS)

McLane, V.; Nordborg, C.; Lemmel, H.D.; Manokhin, V.N.

1988-01-01

The cooperating Nuclear Reaction Data Centers are involved in the compilation and exchange of nuclear reaction data for incident neutrons, charged particles and photons. Individual centers may also have services in other areas, e.g., evaluated data, nuclear structure and decay data, reactor physics, nuclear safety; some of this information may also be exchanged between interested centers. 20 refs., 1 tab

Memorandum of Understanding between the Kingdom of Belgium and the Kingdom of the Netherlands on early notification of a nuclear accident and exchange of information on the operation of nuclear installations

International Nuclear Information System (INIS)

1991-01-01

This Memorandum of Understanding was concluded on 20 December 1990 and provides for close collaboration between the two countries in the light of the 1986 Vienna Convention on Early Notification of a Nuclear Accidents, the 1984 Agreement between the two countries on mutual assistance in the event of catastrophes and accidents, and the 1987 European Community Council Decision on Community arrangements for the early exchange of information in the event of a radiological emergency. To this end, the Parties agree to respond promptly to requests for consultation or further information, to advise each other of any abnormal increase in radioactivity in their respective territories whatever its source, and to exchange information concerning national developments in the peaceful uses of nuclear energy and relevant laws. (NEA)

Atucha I nuclear power plant: repair works in QK02W01 moderator system heat exchanger

International Nuclear Information System (INIS)

Olivieri, Luis E.; Zanni, Pablo A.

2000-01-01

Atucha I nuclear power plant moderator system operates with highly radioactive heavy water, a pressure of 115 Bar and temperatures of about 200 C degrees. In March 2000, an increasing leakage of heavy water to the conventional thermal circuit was detected, conducting the plant to a shut down. The development of a number of actions and measures were taken, in order to plug this leakage. The leakage was found in a heat exchanger, which is located in a place of difficult access, with a high radiological yield and which, according to design, it was not considered to be mechanically repaired. It is a U bend tubes heat exchanger, weighting about 20 tons, and with a heavy water flow of 800 tons/h on the primary circuit, and 950 tons/h of ordinary water on the secondary side. Foreseeing this event, it had been designed and constructed special equipment and procedures, by means of a contract, with the Company INVAP SA. Repair works were carried out within a period of eighty-six (86) days, from which, forty five days were used to repair the component itself. A considerable amount of time was used to prepare simulators and the training of personnel. Due to the high radiological yield and the strict care of radiological standards, it was necessary the participation of 300 persons, integrating a collective dose of 4,86 Sv-m. It was necessary the construction of platforms and auxiliary stairs so as to make the work place accessible, as well as lifting and movement devices for heavy components, since this area does not have such kind of facilities. Welding and cutting machines remote controlled as well as manipulators which operated in front of the exchanger tube sheet were used. The aim was the reduction of dose values as much as possible. Special shielding were developed and in some cases it was necessary the adoption of drastic measures such as the cutting of bolts or pipes. The failure was detected and the tube was plugged. Also were plugged those tubes with wall thickness

Summary of the contractor information exchange meeting for improving the safety of Soviet-Designed Nuclear Power Plants, February 19, 1997

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-04-01

This report summarizes a meeting held on February 19, 1997, in Washington, D.C. The meeting was held primarily to exchange information among the contractors involved in the U.S. Department of Energy`s efforts to improve the safety of Soviet-designed nuclear power plants. Previous meetings have been held on December 5-6, 1995, and May 22, 1996. The meetings are sponsored by the U.S. Department of Energy and coordinated by the Pacific Northwest National Laboratory. The U.S. Department of Energy works with countries to increase the level of safety at 63 Soviet-designed nuclear reactors operating in Armenia, Bulgaria, the Czech Republic, Hungary, Lithuania, Russia, Slovakia, and Ukraine. The work is implemented largely by commercial companies and individuals who provide technologies and services to the countries with Soviet-designed nuclear power plants. Attending the meeting were 71 representatives of commercial contractors, the U.S. Department of Energy, the U.S. Department of State, national laboratories, and other federal agencies. The presentations and discussions that occurred during the exchange are summarized in this report. While this report captures the general presentation and discussion points covered at the meeting, it is not a verbatim, inclusive record. To make the report useful, information presented at the meeting has been expanded to clarify issues, respond to attendees` requests, or place discussion points in a broader programmatic context. Appendixes A through F contain the meeting agenda, list of attendees, copies of presentation visuals and handouts, the Strategy Document discussed at the meeting, and a summary of attendees` post-meeting evaluation comments. As with past information exchanges, the participants found this meeting valuable and useful. In response to the participant`s requests, a fourth information exchange will be held later in 1997.

Summary of the contractor information exchange meeting for improving the safety of Soviet-Designed Nuclear Power Plants, February 19, 1997

International Nuclear Information System (INIS)

1997-04-01

This report summarizes a meeting held on February 19, 1997, in Washington, D.C. The meeting was held primarily to exchange information among the contractors involved in the U.S. Department of Energy's efforts to improve the safety of Soviet-designed nuclear power plants. Previous meetings have been held on December 5-6, 1995, and May 22, 1996. The meetings are sponsored by the U.S. Department of Energy and coordinated by the Pacific Northwest National Laboratory. The U.S. Department of Energy works with countries to increase the level of safety at 63 Soviet-designed nuclear reactors operating in Armenia, Bulgaria, the Czech Republic, Hungary, Lithuania, Russia, Slovakia, and Ukraine. The work is implemented largely by commercial companies and individuals who provide technologies and services to the countries with Soviet-designed nuclear power plants. Attending the meeting were 71 representatives of commercial contractors, the U.S. Department of Energy, the U.S. Department of State, national laboratories, and other federal agencies. The presentations and discussions that occurred during the exchange are summarized in this report. While this report captures the general presentation and discussion points covered at the meeting, it is not a verbatim, inclusive record. To make the report useful, information presented at the meeting has been expanded to clarify issues, respond to attendees' requests, or place discussion points in a broader programmatic context. Appendixes A through F contain the meeting agenda, list of attendees, copies of presentation visuals and handouts, the Strategy Document discussed at the meeting, and a summary of attendees' post-meeting evaluation comments. As with past information exchanges, the participants found this meeting valuable and useful. In response to the participant's requests, a fourth information exchange will be held later in 1997

Development of heat exchangers for nuclear service

International Nuclear Information System (INIS)

Hodge, R.I.; Dalrymple, D.G.

1976-01-01

Unusual design constraints, due to tube vibration, are called for when tube-in-shell heat exchangers are incorporated into CANDU type reactor power plants. CRNL has programs studying tube excitation and response, flow conditions, and the fretting process in such exchangers, tube plugging techniques, and eddy current scanning systems for inside bores of full-length tubes. (E.C.B.)

Nuclear deterrence in the 21. century. Lessons from the cold war for a new era of strategic piracy

International Nuclear Information System (INIS)

Delpech, Therese

2013-01-01

Deterrence remains a primary doctrine for dealing with the threat of nuclear weapons in the 21. century. In this book, the author calls for a renewed intellectual effort to address the relevance of the traditional concepts of first strike, escalation, extended deterrence, and other Cold War-era strategies in today's complex world of additional superpowers (e.g., China), smaller nuclear powers (e.g., Pakistan and North Korea), and non-state actors (e.g., terrorists), as well as the extension of defense and security analysis to new domains, such as outer space and cyber-space. The author draws upon the lessons of the bipolar Cold War era to illustrate new concepts of deterrence that properly account for the variety of nuclear actors, the proliferation of missiles and thermonuclear weapons, and the radical ideologies that all are part of the nuclear scene today. Contents: 1- Introduction, 2 - Why Is This Subject Important?, 3 - Concepts, 4 - Lessons from Crises, 5 - The Age of Small Powers, 6 - Ahead of Us: The Big Piracy Game?, 7 - Space and Cyber-deterrence

Desalting device for nuclear power plants

International Nuclear Information System (INIS)

Shinmura, Akira; Mizumachi, Wataru.

1981-01-01

Purpose: To prevent heated steams and sea water from mixing even in the failures of heat transfer pipes for sea water heating heat exchangers. Constitution: Heating pipes from the nuclear reactor are kept from direct contact with sea water. Specifically, heat exchange is at first carried out in a first heat exchanger between the heated steams from the nuclear reactor and highly pressurized heat exchanging fluid (For example, water). Then, next heat exchange is carried out in a second heat exchanger between the heat exchanging fluid referred to above and the sea water to increase the temperature of the latter. That is, a closed heat transfer loop under high pressure is provided between the sea water and the heat source on the side of the nuclear reactor, so that the sea water and the heat source of the nuclear reactor are kept from direct contact. (Ikeda, J.)

Next Generation Nuclear Plant Intermediate Heat Exchanger Materials Research and Development Plan (PLN-2804)

Energy Technology Data Exchange (ETDEWEB)

J. K. Wright

2008-04-01

DOE has selected the High Temperature Gas-cooled Reactor (HTGR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production. It will have an outlet gas temperature in the range of 900°C and a plant design service life of 60 years. The reactor design will be a graphite moderated, helium-cooled, prismatic or pebble-bed reactor and use low-enriched uranium, Tri-Isotopic (TRISO)-coated fuel. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Materials Research and Development (R&D) Program is responsible for performing R&D on likely NGNP materials in support of the NGNP design, licensing, and construction activities. Today’s high-temperature alloys and associated ASME Codes for reactor applications are approved up to 760°C. However, some primary system components, such as the Intermediate Heat Exchanger (IHX) for the NGNP will require use of materials that can withstand higher temperatures. The thermal, environmental, and service life conditions of the NGNP will make selection and qualification of some high-temperature materials a significant challenge. Examples include materials for the core barrel and core internals, such as the control rod sleeves. The requirements of the materials for the IHX are among the most demanding. Selection of the technology and design configuration for the NGNP must consider both the cost and risk profiles to ensure that the demonstration plant establishes a sound foundation for future commercial deployments. The NGNP challenge is to achieve a significant advancement in nuclear technology while at the same time setting the stage for an economically viable deployment of the new technology in the commercial sector soon after 2020. A number of solid solution strengthened nickel based alloys have been considered for

Relativistic four-component calculations of indirect nuclear spin-spin couplings with efficient evaluation of the exchange-correlation response kernel

Energy Technology Data Exchange (ETDEWEB)

Křístková, Anežka; Malkin, Vladimir G. [Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-84536 Bratislava (Slovakia); Komorovsky, Stanislav; Repisky, Michal [Centre for Theoretical and Computational Chemistry, University of Tromsø - The Arctic University of Norway, N-9037 Tromsø (Norway); Malkina, Olga L., E-mail: olga.malkin@savba.sk [Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-84536 Bratislava (Slovakia); Department of Inorganic Chemistry, Comenius University, Bratislava (Slovakia)

2015-03-21

In this work, we report on the development and implementation of a new scheme for efficient calculation of indirect nuclear spin-spin couplings in the framework of four-component matrix Dirac-Kohn-Sham approach termed matrix Dirac-Kohn-Sham restricted magnetic balance resolution of identity for J and K, which takes advantage of the previous restricted magnetic balance formalism and the density fitting approach for the rapid evaluation of density functional theory exchange-correlation response kernels. The new approach is aimed to speedup the bottleneck in the solution of the coupled perturbed equations: evaluation of the matrix elements of the kernel of the exchange-correlation potential. The performance of the new scheme has been tested on a representative set of indirect nuclear spin-spin couplings. The obtained results have been compared with the corresponding results of the reference method with traditional evaluation of the exchange-correlation kernel, i.e., without employing the fitted electron densities. Overall good agreement between both methods was observed, though the new approach tends to give values by about 4%-5% higher than the reference method. On the average, the solution of the coupled perturbed equations with the new scheme is about 8.5 times faster compared to the reference method.

Relativistic four-component calculations of indirect nuclear spin-spin couplings with efficient evaluation of the exchange-correlation response kernel

International Nuclear Information System (INIS)

Křístková, Anežka; Malkin, Vladimir G.; Komorovsky, Stanislav; Repisky, Michal; Malkina, Olga L.

2015-01-01

In this work, we report on the development and implementation of a new scheme for efficient calculation of indirect nuclear spin-spin couplings in the framework of four-component matrix Dirac-Kohn-Sham approach termed matrix Dirac-Kohn-Sham restricted magnetic balance resolution of identity for J and K, which takes advantage of the previous restricted magnetic balance formalism and the density fitting approach for the rapid evaluation of density functional theory exchange-correlation response kernels. The new approach is aimed to speedup the bottleneck in the solution of the coupled perturbed equations: evaluation of the matrix elements of the kernel of the exchange-correlation potential. The performance of the new scheme has been tested on a representative set of indirect nuclear spin-spin couplings. The obtained results have been compared with the corresponding results of the reference method with traditional evaluation of the exchange-correlation kernel, i.e., without employing the fitted electron densities. Overall good agreement between both methods was observed, though the new approach tends to give values by about 4%-5% higher than the reference method. On the average, the solution of the coupled perturbed equations with the new scheme is about 8.5 times faster compared to the reference method

Standardizing exchange formats

International Nuclear Information System (INIS)

Lemmel, H.D.; Schmidt, J.J.

1992-01-01

An international network of co-operating data centres is described who maintain identical data bases which are simultaneously updated by an agreed data exchange procedure. The agreement covers ''data exchange formats'' which are compatible to the centres' internal data storage and retrieval systems which remain different, optimized at each centre to the available computer facilities and to the needs of the data users. Essential condition for the data exchange is an agreement on common procedures for the data exchange is an agreement on common procedures for the data compilation, including critical data analysis and validation. The systems described (''EXFOR'', ''ENDF'', ''CINDA'') are used for ''nuclear reaction data'', but the principles used for data compilation and exchange should be valid also for other data types. (author). 24 refs, 4 figs

International exchange of safety and licensing information

International Nuclear Information System (INIS)

Lafleur, J.D. Jr.; Hauber, R.D.; Chenier, D.M.

1977-01-01

A network of formal and informal bilateral arrangements for the exchange of nuclear safety information is being established by the US Nuclear Regulatory Commission. For developing countries such arrangements can provide ready access to the extensive, fully documented safety analyses and safety research results that USNRC has accumulated. USNRC has been receiving foreign visitors at a rate of about 500 per year, largely for discussions of safety and licensing questions related to light water reactors. Exchanges also are taking place on the safety of advanced reactors. A special interest of the USNRC is in providing for reciprocal communication, at the earliest possible time, of important problems, decisions and other actions on nuclear safety matters. For example, it is essential that a newly discovered problem in a nuclear reactor be brought immediately to the attention of other governments that are responsible for the safety of similar reactors. Definite progress has been made in the USA in defining categories of information that USNRC can receive in confidence from foreign countries, and can protect from disclosure under the US Freedom of Information Act. Certain exchanges have taken place on this basis. Experience in the establishment and operation of USNRC's bilateral exchange arrangements is summarized. A typical exchange with the regulatory authority of a country building its first power reactor is described. (author)

Climate Impact of a Regional Nuclear Weapons Exchange: An Improved Assessment Based On Detailed Source Calculations

Science.gov (United States)

Reisner, Jon; D'Angelo, Gennaro; Koo, Eunmo; Even, Wesley; Hecht, Matthew; Hunke, Elizabeth; Comeau, Darin; Bos, Randall; Cooley, James

2018-03-01

We present a multiscale study examining the impact of a regional exchange of nuclear weapons on global climate. Our models investigate multiple phases of the effects of nuclear weapons usage, including growth and rise of the nuclear fireball, ignition and spread of the induced firestorm, and comprehensive Earth system modeling of the oceans, land, ice, and atmosphere. This study follows from the scenario originally envisioned by Robock, Oman, Stenchikov, et al. (2007, https://doi.org/10.5194/acp-7-2003-2007), based on the analysis of Toon et al. (2007, https://doi.org/10.5194/acp-7-1973-2007), which assumes a regional exchange between India and Pakistan of fifty 15 kt weapons detonated by each side. We expand this scenario by modeling the processes that lead to production of black carbon, in order to refine the black carbon forcing estimates of these previous studies. When the Earth system model is initiated with 5 × 109 kg of black carbon in the upper troposphere (approximately from 9 to 13 km), the impact on climate variables such as global temperature and precipitation in our simulations is similar to that predicted by previously published work. However, while our thorough simulations of the firestorm produce about 3.7 × 109 kg of black carbon, we find that the vast majority of the black carbon never reaches an altitude above weather systems (approximately 12 km). Therefore, our Earth system model simulations conducted with model-informed atmospheric distributions of black carbon produce significantly lower global climatic impacts than assessed in prior studies, as the carbon at lower altitudes is more quickly removed from the atmosphere. In addition, our model ensembles indicate that statistically significant effects on global surface temperatures are limited to the first 5 years and are much smaller in magnitude than those shown in earlier works. None of the simulations produced a nuclear winter effect. We find that the effects on global surface temperatures

Probes for inspections of heat exchanges installed at nuclear power plants type PWR by eddy current method

International Nuclear Information System (INIS)

Silva, Alonso F.O.

2007-01-01

From all non destructive examination methods usable to perform integrity evaluation of critical equipment installed at nuclear power plants (NPP), eddy current test (ET) may be considered the most important one, when examining heat exchangers. For its application, special probes and reference calibration standards are employed. In pressurized water reactor (PWR) NPPs, a particularly critical equipment is the steam generator (SG), a huge heat exchanger that contains thousands of U-bend thin wall tubes. Due to its severe working conditions (pressure and temperature), that component is periodically examined by means of ET. In this paper a revision of the operating fundamentals of the main ET probes, used to perform SG inspections is presented. (author)

Integrated system of nuclear reactor and heat exchanger

International Nuclear Information System (INIS)

McDonald, B.N.; Schluderberg, D.C.

1977-01-01

The invention concerns PWRs in which the heat exchanger is associated with a pressure vessel containing the core and from which it can be selectively detached. This structural configuration applies to electric power generating uses based on land or on board ships. An existing reactor of this kind is fitted with a heat exchanger in which the tubes are 'U' shaped. This particular design of heat exchangers requires that the ends of the curved tubes be solidly maintained in a tube plate of great thickness, hence difficult to handle and to fabricate and requiring unconventional fine control systems for the control rods and awkward coolant pump arrangements. These complications limit the thermal power of the system to level below 100 megawatts. On the contrary, the object of this invention is to provide a one-piece PWR reactor capable of reaching power levels of 1500 thermal megawatts at least. For this, a pressure vessel is provided in the cylindrical assembly with not only a transversal separation on a plane located between the reactor and the heat exchanger but also a cover selectively detachable which supports the fine control gear of the control rods. Removing the cover exposes a part of the heat exchanger for easy inspection and maintenance. Further, the heat exchanger can be removed totally from the pressure vessel containing the core by detaching the cylindrical part, which composes the heat exchanger section, from the part that holds the reactor core on a level with the transversal separation [fr

Heat exchanger cleaning

International Nuclear Information System (INIS)

Gatewood, J.R.

1980-01-01

A survey covers the various types of heat-exchange equipment that is cleaned routinely in fossil-fired generating plants, the hydrocarbon-processing industry, pulp and paper mills, and other industries; the various types, sources, and adverse effects of deposits in heat-exchange equipment; some details of the actual procedures for high-pressure water jetting and chemical cleaning of some specific pieces of equipment, including nuclear steam generators. (DN)

Proceedings of the fourth information exchange meeting on nuclear production of hydrogen

International Nuclear Information System (INIS)

2010-01-01

The use of hydrogen, both as feedstock for the industry (oil and chemical) and as an energy carrier, is expected to grow substantially during the coming decades. The current predominant method of producing hydrogen by steam-reforming methane (from natural gas) is not sustainable and has environmental drawbacks, including the emission of greenhouse gasses (GHGs). Nuclear energy offers a way to produce hydrogen from water without depleting natural gas, a valuable natural resource, and without the emission of GHGs. The OECD Nuclear Energy Agency (NEA) has conducted a number of information exchange meetings with the objective of stimulating progress in the development of nuclear production of hydrogen. These meetings, held in 2000 in Paris, France, in 2003 in Argonne, Illinois, USA, and in 2005 in Oarai, Japan, were well-attended and very successful. It is hoped that the information presented at fourth meeting and contained in these proceedings may be useful in advancing the objective of achieving economically viable, sustainable and emission-free production of hydrogen. The need for a sustainable supply of clean energy is one of the main problems facing the world. Among the various energy technologies which may be considered (including hydro, wind, solar, geo-thermal, wave and tidal), only nuclear - through the use of fast-neutron fission reactors - is capable of delivering the copious quantities of sustainable energy that will be required. In view of this, one of the means under consideration for achieving the objective of nuclear-produced hydrogen is enhanced international cooperation, including the establishment of one or more OECD/NEA joint projects. In this respect, it is worth noting that similar joint projects undertaken in the past (for example, the Dragon Project and the Halden Reactor Project) have been highly beneficial and have provided significant amounts of useful information to the sponsoring countries at shared costs. This report describes the

Corrosion of steel drums containing cemented ion-exchange resins as intermediate level nuclear waste

Science.gov (United States)

Duffó, G. S.; Farina, S. B.; Schulz, F. M.

2013-07-01

Exhausted ion-exchange resins used in nuclear reactors are immobilized by cementation before being stored. They are contained in steel drums that may undergo internal corrosion depending on the presence of certain contaminants. The objective of this work is to evaluate the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins with different aggressive species. The corrosion potential and the corrosion rate of the steel, and the electrical resistivity of the matrix were monitored for 900 days. Results show that the cementation of ion-exchange resins seems not to pose special risks regarding the corrosion of the steel drums. The corrosion rate of the steel in contact with cemented ion-exchange resins in the absence of contaminants or in the presence of 2.3 wt.% sulphate content remains low (less than 0.1 μm/year) during the whole period of the study (900 days). The presence of chloride ions increases the corrosion rate of the steel at the beginning of the exposure but, after 1 year, the corrosion rate drops abruptly reaching a value close to 0.1 μm/year. This is probably due to the lack of water to sustain the corrosion process. When applying the results obtained in the present work to estimate the corrosion depth of the steel drums containing the cemented radioactive waste after a period of 300 years, it is found that in the most unfavourable case (high chloride contamination), the corrosion penetration will be considerably lower than the thickness of the wall of the steel drums. Cementation of ion-exchange resins does not seem to pose special risks regarding the corrosion of the steel drums that contained them; even in the case the matrix is highly contaminated with chloride ions.

Characterization and disposal of ion exchange resins used in nuclear installations

International Nuclear Information System (INIS)

Flores E, R.M.; Ortiz O, H.B.; Olguin G, M.T.; Emeterio H, M.; Garcia M, H.

2006-01-01

To dispose of an appropriate way the used ion exchange resins so much in the pool water purification systems of the TRIGA Mark III reactor like in the JS6500 gamma irradiator, of the National Institute of Nuclear Research, were carried out a series of analytic nuclear techniques and complementary conventional to those recommended by the ASTM, with the object of to control and to manage 14 lots of worn out resins appropriately. For its were identified the radioactive isotopes, the resins type, the grade of chemical pollution and the physicochemical degradation of the same ones. The lots of resins that didn't contain radioactive isotopes its were regenerated in an usual way, as long as those that if they controlled them they selected options for its final disposition. The first selected option was the extraction method of ion radioactive isotopes, concentrating the elution product by evaporation. As second option it was carried out the resins stabilization damaged by micro-encapsulation by forged to ambient temperature, using an organic polymer. Previous to the immobilization the resins were pretreated by vacuum drying, pulverization and thermal drying, however before carrying out this last, it was carried out a thermal gravimetric analysis to determine the drying conditions of the resins avoiding its chemical decomposition. (Author)

Ion exchange and hydrolysis reactions in zeolites

International Nuclear Information System (INIS)

Harjula, Risto.

1993-09-01

Among other uses, zeolites are efficient cation exchangers for aquatic pollution control. At present they they are mainly used in nuclear waste effluent treatment and in detergency. In the thesis, several ion exchange equilibria, important in these main fields of zeolite applications, were studied, with special emphasis on the formulation and calculation of the equilibria. The main interest was the development of thermodynamic formulations for the calculation of zeolite ion exchange equilibria in solutions of low or very low (trace) ion concentration, which are relevant for the removal of trace pollutants, such as radionuclides, from waste waters. Two groups of zeolite-cation systems were studied. First, binary Ca 2+ /Na + exchange in zeolites X and Y, which are of interest for detergency applications. Second, binary Cs + /Na + and Cs + /K + exchanges, and ternary Cs + /Na + /K + exchange in mordenite, which are important in nuclear waste effluent treatment. The thesis is based on five previous publications by author. (100 refs., 7 figs.)

Summary of JRC activities related to European-wide exchange of radiological information during nuclear emergencies

International Nuclear Information System (INIS)

De Court, M.; Vries de, G.; Galmarini, S.

2003-01-01

Full text: The large transboundary effects of the radioactive release during the Chernobyl accident evidenced the need for international provisions for data and Information exchange. The JRC, in its EC support activity to DG TREN H.4, called REM (Radioactivity Environmental Monitoring), has more than 10 years experience in developing systems to make early notification and reliable radiological information exchange available to the EU member states in case of nuclear accidents. The aim and status of these systems are described: 1.)ECURIE: The legal basis for the EC systems is the Council Decision 87/600 of 14 December 1987. It resulted in the ECURIE network which allows the EU Member States and Switzerland to notify an accident and to subsequently exchange the radiological information as required by this Council decision. The underlying information exchange code (C.1. structure) does not only provide radiological measurements, but also predicted values, site meteorological data and decisions taken. Software was developed to facilitate coding and decoding of the messages. Initially the messages were transmitted by telex. The latest software (CoDecS, in use since the beginning of 2001) uses ISDN and Internet for the Information exchange. lt runs an the Windows NT and 2000 platforms. Regular exercises test the communication system and the software. In view of improving the efficiency of data and Information transfer for their common Member States, the IAEA and the EC are harmonizing ECURIE and the ENATOM early notification system. A first result has been the definition of an enhanced CIS format. Modifications will be made to the CoDecs software and to the IAEA - ENAC website so that information can be exchanged between the two systems in an automated manner. The EC wishes to extend the ECURIE network to the EU candidate countries. The official agreements are in an advanced state and participation of many candidate countries is foreseen by the end of 2003. It is

Heat exchange apparatus

International Nuclear Information System (INIS)

Thurston, G.C.; McDaniels, J.D.; Gertsch, P.R.

1979-01-01

The present invention relates to heat exchangers used for transferring heat from the gas cooled core of a nuclear reactor to a secondary medium during standby and emergency conditions. The construction of the heat exchanger described is such that there is a minimum of welds exposed to the reactor coolant, the parasitic heat loss during normal operation of the reactor is minimized and the welds and heat transfer tubes are easily inspectable. (UK)

Immobilization of ion exchange radioactive resins of the TRIGA Mark III nuclear reactor

International Nuclear Information System (INIS)

Garcia M, H.; Emeterio H, M.; Canizal S, C.

1999-01-01

This work has the objective to develop the process and to define the agglutinating material which allows the immobilization of the ion exchange radioactive resins coming from the TRIGA Mark III nuclear reactor contaminated with Ba-133, Co-60, Cs-137, Eu-152, and Mn-54 through the behavior analysis of different immobilization agents such as: bitumens, cement and polyester resin. According to the International Standardization the archetype samples were observed with the following tests: determination of free liquid, leaching, charge resistance, biodegradation, irradiation, thermal cycle, burned resistance. Generally all the tests were satisfactorily achieved, for each agent. Therefore, the polyester resin could be considered as the main immobilizing. (Author)

Canadians, nuclear weapons, and the Cold War security dilemma

International Nuclear Information System (INIS)

Eaton, M.A.

2007-01-01

This dissertation provides a history of Canadian ideas about nuclear weapons from the late 1950s until the end of the Trudeau era in 1984. Throughout this period, Canadians reacted to the insecurity they felt in the world around them by expressing many conflicting, often irreconcilable views about a range of nuclear weapon issues, including Canada's acquisition of nuclear warheads in 1963, the U.S. ABM program in the 1960s and early 1970s, the role of Canadian nuclear technology in the development of India's first nuclear explosion, and the Trudeau government's decision to allow the U.S. military to test cruise missiles in northern Canada The dissertation concludes with an examination of the emergence of a broadly-based, increasingly mainstream and influential anti-nuclear movement in the early 1980s, the clearest manifestation of the insecurity Canadians experienced at the time. .The nuclear debates examined in this dissertation reveal that Canadians were divided over nuclear weapons, nuclear strategy, the arms race, proliferation, and arms control and disarmament. In particular, they came to fundamentally different conclusions about how Canada's nuclear weapon policies, and its support for the nuclear policies of its alliances, would contribute to international stability and order. Some believed that their security rested on the maintenance of a strong Western nuclear deterrent and supported Canada contributing to its credibility; others believed that the constant modernisation of nuclear arsenals fuelled by the superpower arms race posed a serious threat to their security. This conceptual dilemma-the security through nuclear strength argument versus the fear that the quest for security through quantitative and qualitative improvements of nuclear stockpiles increased the likelihood of nuclear war-left Canadians divided over the value and utility of nuclear weapons and the strategies developed around them. At the same time, Canadians' ideas about nuclear weapons

Canadians, nuclear weapons, and the Cold War security dilemma

Energy Technology Data Exchange (ETDEWEB)

Eaton, M.A

2007-07-01

This dissertation provides a history of Canadian ideas about nuclear weapons from the late 1950s until the end of the Trudeau era in 1984. Throughout this period, Canadians reacted to the insecurity they felt in the world around them by expressing many conflicting, often irreconcilable views about a range of nuclear weapon issues, including Canada's acquisition of nuclear warheads in 1963, the U.S. ABM program in the 1960s and early 1970s, the role of Canadian nuclear technology in the development of India's first nuclear explosion, and the Trudeau government's decision to allow the U.S. military to test cruise missiles in northern Canada The dissertation concludes with an examination of the emergence of a broadly-based, increasingly mainstream and influential anti-nuclear movement in the early 1980s, the clearest manifestation of the insecurity Canadians experienced at the time. .The nuclear debates examined in this dissertation reveal that Canadians were divided over nuclear weapons, nuclear strategy, the arms race, proliferation, and arms control and disarmament. In particular, they came to fundamentally different conclusions about how Canada's nuclear weapon policies, and its support for the nuclear policies of its alliances, would contribute to international stability and order. Some believed that their security rested on the maintenance of a strong Western nuclear deterrent and supported Canada contributing to its credibility; others believed that the constant modernisation of nuclear arsenals fuelled by the superpower arms race posed a serious threat to their security. This conceptual dilemma-the security through nuclear strength argument versus the fear that the quest for security through quantitative and qualitative improvements of nuclear stockpiles increased the likelihood of nuclear war-left Canadians divided over the value and utility of nuclear weapons and the strategies developed around them. At the same time, Canadians

Administrative arrangement between the United States Nuclear Regulatory Commission and the Atomic Energy Control Board of Canada for co-operation and the exchange of information in nuclear regulatory matters

International Nuclear Information System (INIS)

1989-06-01

This Administrative Arrangement covers co-operation and exchange of technical information relating to the regulation of the health, safety, security, safeguards and environmental protection aspects of nuclear facilities and materials as well as of radioactive substances and waste. The Arrangement was concluded for five years and is renewable [fr

Incineration of spent ion exchange resin

International Nuclear Information System (INIS)

Hasegawa, Chiaki

1990-01-01

It is a pressing need to reduce radioactive waste which is generated from the maintenance and operation of a nuclear power plant. Incineration of low level combustible solid waste such as polyethylene seats, paper and others have been successfully performed since 1984 at the Shimane Nuclear Power Station. Furthermore, for extending incineration treatment to spent ion exchange resin, the incineration test was carried out in 1989. However, as the cation exchange resin contains sulfur and then incineration generates SOx gases, so the components of this facility will be in a corrosive environment. We surveyed incineration conditions to improve the corrosive environment at the exhaust gas treatment system. This paper includes these test results and improved method to incinerate spent ion exchange resin. (author)

Preliminary thermal sizing of intermediate heat exchanger for NHDD system

International Nuclear Information System (INIS)

Kim, Chan Soo; Hong, Sung Deok; Kim, Yong Wan; Chang, Jongh Wa

2009-01-01

Nuclear Hydrogen Development and Demonstration (NHDD) system is a Very High Temperature gascooled Reactor (VHTR) coupled with hydrogen production systems. Intermediate heat exchanger transfers heat from the nuclear reactor to the hydrogen production system. This study presented the sensitivity analysis on a preliminary thermal sizing of the intermediate heat exchanger. Printed Circuit Heat Exchanger (PCHE) was selected for the thermal sizing because the printed circuit heat exchanger has the largest compactness among the heat exchanger types. The analysis was performed to estimate the effect of key parameters including the operating condition of the intermediate system, the geometrical factors of the PCHE, and the working fluid of the intermediate system.

Next Generation Nuclear Plant Steam Generator and Intermediate Heat Exchanger Materials Research and Development Plan

Energy Technology Data Exchange (ETDEWEB)

J. K. Wright

2010-09-01

DOE has selected the High Temperature Gas-cooled Reactor (HTGR) design for the Next Generation Nuclear Plant (NGNP) Project. The NGNP will demonstrate the use of nuclear power for electricity and hydrogen production. It will have an outlet gas temperature in the range of 900°C and a plant design service life of 60 years. The reactor design will be a graphite moderated, helium-cooled, prismatic or pebble-bed reactor and use low-enriched uranium, Tri-Isotopic (TRISO)-coated fuel. The plant size, reactor thermal power, and core configuration will ensure passive decay heat removal without fuel damage or radioactive material releases during accidents. The NGNP Materials Research and Development (R&D) Program is responsible for performing R&D on likely NGNP materials in support of the NGNP design, licensing, and construction activities. Today’s high-temperature alloys and associated ASME Codes for reactor applications are approved up to 760°C. However, some primary system components, such as the Intermediate Heat Exchanger (IHX) for the NGNP will require use of materials that can withstand higher temperatures. The thermal, environmental, and service life conditions of the NGNP will make selection and qualification of some high-temperature materials a significant challenge. Examples include materials for the core barrel and core internals, such as the control rod sleeves. The requirements of the materials for the IHX are among the most demanding. Selection of the technology and design configuration for the NGNP must consider both the cost and risk profiles to ensure that the demonstration plant establishes a sound foundation for future commercial deployments. The NGNP challenge is to achieve a significant advancement in nuclear technology while at the same time setting the stage for an economically viable deployment of the new technology in the commercial sector soon after 2020. A number of solid solution strengthened nickel based alloys have been considered for

Reactor fuel exchanging facility

International Nuclear Information System (INIS)

Kubota, Shin-ichi.

1981-01-01

Purpose: To enable operation of an emergency manual operating mechanism for a fuel exchanger with all operatorless trucks and remote operation of a manipulator even if the exchanger fails during the fuel exchanging operation. Constitution: When a fuel exchanging system fails while connected to a pressure tube of a nuclear reactor during a fuel exchanging operation, a stand-by self-travelling truck automatically runs along a guide line to the position corresponding to the stopping position at that time of the fuel exchanger based on a command from a central control chamber. At this time the truck is switched to manual operation, and approaches the exchanger while being monitored through a television camera and then stops. Then, a manipurator is connected to the emergency manual operating mechanism of the exchanger, and is operated through necessary emergency steps by driving the snout, the magazine, the grab or the like in the exchanger in response to the problem, and necessary operations for the emergency treatment are thus performed. (Sekiya, K.)

Fock exchange in meson theories of nuclei

International Nuclear Information System (INIS)

Bolsterli, M.

1986-01-01

The Fock exchange term in meson field theories of nuclear systems is shown to arise from a two-loop ground-state self-energy diagram. Evaluation of this diagram gives the relativistic or semirelativistic analog of the Fock exchange energy; it differs from the nucleon-nucleon Fock energy in including retardation effects. In finite meson-field theories of nuclear systems, the variational nature of the meson-field analog of the Hartree-Fock energy functional can be further elucidated. 4 refs

Leach studies on cement-solidified ion exchange resins from decontamination processes at operating nuclear power stations

International Nuclear Information System (INIS)

McIsaac, C.V.; Akers, D.W.; McConnell, J.W.; Morcos, N.

1992-01-01

The effects of varying pH and leachant compositions on the physical stability and leachability of radionuclides and chelating agents were determined for cement-solidified decontamination ion-exchange resin wastes collected from two operating commercial light water reactors. Small scale waste-form specimens were collected during waste solidifications performed at the Brunswick Steam Electric Plant Unit 1 and at the James A. FitzPatrick Nuclear Power Station. The collected specimens were leach tested, and their compressive strength was measured in accordance with the Nuclear Regulatory Commission's ''Technical Position on Waste Form'' (Revision 1), from the Low-Level Waste Management Branch. Leachates from these studies were analyzed for radionuclides, selected transition metals, and chelating agents to assess the leachability of these waste form constituents. Leachants used for the study were deionized water, simulated seawater, and groundwater compositions similar to those found at Barnwell, South Carolina and Hanford, Washington. Results of this study indicate that initial leachant pH does not affect leachate pH or releases from cement-solidified decontamination ion-exchange resin waste forms. However, differences in leachant composition and the presence of chelating agents may affect the releases of radionuclides and chelating agents. In addition, results from this study indicate that the cumulative releases of radionuclides and chelating agents observed for forms that disintegrated were similar to those for forms that maintained their general physical integrity

Optimization of the operational parameters in isotopic exchange installations. ROMAG PROD plant production of heavy water for the nuclear power plant

International Nuclear Information System (INIS)

Pop, A.

2002-01-01

The ROMAG PROD heavy water plant at Drobeta Turnu Severin together with SN Nuclearelectrica Company and Nuclear Fuel Plant at Pitesti are the most important pillars the National Nuclear Program is based on. The plant became operational on 17th July 1988, was later modernized and now reached in the field a leading position known world wide. There are described the modifications adopted to the two stages of the isotopic exchange installation besides some refurbishment measures of general character. The increase of discharge flow rate in cool columns vs hot columns resulted in a rise of technological regime stability and the feeding rate. Also in the first stage the stripping vapor injection in the hot columns was modified to avoid vacuum excursion in the columns. In the second stage two isotopic exchange trays were replaced with dry trays to obtain drop separation at the cool column top. All the trays from the isotopic exchange section of the cool column were replaced by trays from the hot column. The thermal exchange zone in the cool column was modified by introducing trays with number of holes. The gas flow rate of the stage two compressor was adapted to the design requirements. By these changes of the parameters in the original design were substantially improved, the operation became easier, more secure and safer for the environment while the production of the heavy water doubled between 1995 and 2001 reaching a value of 163 t/y in 2001

Evaluation of ion exchange resin performance in Kuosheng nuclear power plant

International Nuclear Information System (INIS)

Wen, T.J.; Chen Huang, T.; Liu, W.C.; Liu, T.C.; Shen, S.C.

2004-01-01

Different types and brands of bead and powdered ion exchange resin have been widely used in condensate and reactor water clean-up system in Boiling Water Reactors (BWRs). The importance of primary coolant quality control has been well recognized. Recently, some measures both in promoting the conductivity of reactor water and minimizing iron crud of feed-water have been recommended by the Institute of Nuclear Energy Research. The variation of water quality between the condensate and reactor water is closely related with the performance of condensate polisher and precoat condition. In order to ensure optimization of water chemistry quality in reactor system, historical water chemistry data have been reviewed and evaluated. The most probable causes of exceeding the chemistry limits and guidelines should be identified and some reasonable corrective actions have been documented as a reference for promoting the water quality and run length extending in the plant normal operation. (author)

Nuclear magnetic relaxation induced by exchange-mediated orientational randomization: longitudinal relaxation dispersion for spin I = 1.

Science.gov (United States)

Nilsson, Tomas; Halle, Bertil

2012-08-07

The frequency dependence of the longitudinal relaxation rate, known as the magnetic relaxation dispersion (MRD), can provide a frequency-resolved characterization of molecular motions in complex biological and colloidal systems on time scales ranging from 1 ns to 100 μs. The conformational dynamics of immobilized proteins and other biopolymers can thus be probed in vitro or in vivo by exploiting internal water molecules or labile hydrogens that exchange with a dominant bulk water pool. Numerous water (1)H and (2)H MRD studies of such systems have been reported, but the widely different theoretical models currently used to analyze the MRD data have resulted in divergent views of the underlying molecular motions. We have argued that the essential mechanism responsible for the main dispersion is the exchange-mediated orientational randomization (EMOR) of anisotropic nuclear (electric quadrupole or magnetic dipole) couplings when internal water molecules or labile hydrogens escape from orientationally confining macromolecular sites. In the EMOR model, the exchange process is thus not just a means of mixing spin populations but it is also the direct cause of spin relaxation. Although the EMOR theory has been used in several studies to analyze water (2)H MRD data from immobilized biopolymers, the fully developed theory has not been described. Here, we present a comprehensive account of a generalized version of the EMOR theory for spin I = 1 nuclides like (2)H. As compared to a previously described version of the EMOR theory, the present version incorporates three generalizations that are all essential in applications to experimental data: (i) a biaxial (residual) electric field gradient tensor, (ii) direct and indirect effects of internal motions, and (iii) multiple sites with different exchange rates. In addition, we describe and assess different approximations to the exact EMOR theory that are useful in various regimes. In particular, we consider the experimentally

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

Quantification of exchangeable and non-exchangeable organically bound tritium (OBT) in vegetation

International Nuclear Information System (INIS)

Kim, S.B.; Korolevych, V.

2013-01-01

The objective of this study is to quantify the relative amounts of exchangeable organically bound tritium (OBT) and non-exchangeable OBT in various vegetables. A garden plot at Perch Lake, where tritium levels are slightly elevated due to releases of tritium from a nearby nuclear waste management area and Chalk River Laboratories (CRL) operations, was used to cultivate a variety of vegetables. Five different kinds of vegetables (lettuce, cabbage, tomato, radish and beet) were studied. Exchangeable OBT behaves like tritium in tissue free water in living organisms and, based on past measurements, accounts for about 20% of the total tritium in dehydrated organic materials. In this study, the percentage of the exchangeable OBT was determined to range from 20% to 57% and was found to depend on the type of vegetables as well as the sequence of the plants exposure to HTO. -- Highlights: ► This study was to quantify the amount of exchangeable OBT compared to non-exchangeable OBT in vegetables. ► The percentage of exchangeable OBT varied between vegetable types and HTO exposure conditions. ► Exchangeable OBT varied from 20 to 36% in un-treated vegetables and from 30 to 57% in treated vegetables

Secondary heat exchanger design and comparison for advanced high temperature reactor

International Nuclear Information System (INIS)

Sabharwall, P.; Kim, E. S.; Siahpush, A.; McKellar, M.; Patterson, M.

2012-01-01

Next generation nuclear reactors such as the advanced high temperature reactor (AHTR) are designed to increase energy efficiency in the production of electricity and provide high temperature heat for industrial processes. The efficient transfer of energy for industrial applications depends on the ability to incorporate effective heat exchangers between the nuclear heat transport system and the industrial process heat transport system. This study considers two different types of heat exchangers - helical coiled heat exchanger and printed circuit heat exchanger - as possible options for the AHTR secondary heat exchangers with distributed load analysis and comparison. Comparison is provided for all different cases along with challenges and recommendations. (authors)

A Soviet view

International Nuclear Information System (INIS)

Tikhonov, S.Y.

1992-01-01

During the past several years, the international situation has changed greatly. Efforts to maintain strategic stability have replaced the desire for strategic superiority. Equally important, new thinking in the Soviet Union has greatly accelerated the political warming between the superpowers. As a result of thee developments, the Soviet Union and the United States have come to the conclusion that a nuclear war cannot be won and should never be fought. These events have drastically reduced the probability of the deliberate use of nuclear or conventional weapons. However, the risk of a military crisis and its consequences still exist. Indeed, the risk of a nuclear exchange is still possible. What has changed, however, is that in the current international climate, a crisis or war may result unintentionally because of misperceptions, misunderstanding, accident, or technical fault. While the probability of this is admittedly small, it remains far greater than that of deliberate conflict. The purpose of this chapter, therefore, is twofold. First, it identifies potential sources of unintended crises and conflicts and recommends appropriate confidence-building measures. Second, it addresses CBMs and their potential roles in nuclear crisis de-escalation

Meson exchange corrections to nuclear weak axial charge density in hard pion model and O+ reversible O- transition in A = 16 nuclei

International Nuclear Information System (INIS)

Jager, H.U.; Kirchbach, M.; Truhlik, E.

1982-01-01

Starting with the hard pion model based on a minimal chiral invariant phenomenological Lagrangian, the two-particle part of the time component of the weak axial-vector current is constructed in the tree-approximation. Pion, rho- and A 1 -meson exchanges are considered. The mesonic exchange operator obtained is applied to describe the purely weak axial 0 + reversible 0 - , ΔT=1 transition in the nuclear A=16 system the muon reaction μ - + 16 O(0 1 + ; T=0) → 16 N(0 1 - ; T=1) + γsub(μ) and beta decay 16 N(0 1 - ; T=1) → 16 O(0 1 + ; T=0) + e - + anti νsub(e). In order to treat nufar structure correlation efects explicit use of shell model wave functions with configuration mixing is made. The large enhancement of the nuclear weak axial charge density with respect to impulse approximation is established

Kinetics of oxygen exchange between bisulfite ion and water as studied by oxygen-17 nuclear magnetic resonance spectroscopy

International Nuclear Information System (INIS)

Horner, D.A.

1984-08-01

The nuclear magnetic relaxation times of oxygen-17 have been measured in aqueous sodium bisulfite solutions in the pH range from 2.5 to 5 as a function of temperature, pH, and S(IV) concentration, at an ionic strength of 1.0 m. The rate law for oxygen exchange between bisulfite ion and water was obtained from an analysis of the data, and is consistent with oxygen exchange occurring via the reaction SO 2 + H 2 O right reversible H + + SHO 3 - . The value of k/sub -1/ is in agreement with relaxation measurements. Direct spectroscopic evidence was found for the existence of two isomers of bisulfite ion: one with the proton bonded to the sulfur (HSO 3 - ) and the other with the proton bonded to an oxygen (SO 3 H - ). (The symbol SHO 3 - in the above chemical equation refers to both isomeric forms of bisulfite ion.) The relative amounts of the two isomers were determined as a function of temperature, and the rate and mechanism of oxygen exchange between the two was investigated. One of the two isomers, presumably SO 3 H - , exchanges oxygens with water much more rapidly than does the other. A two-pulse sequence was developed which greatly diminished the solvent peak in the NMR spectrum

Nuclear potentials due to pion exchange

International Nuclear Information System (INIS)

Robillota, M.R.

1984-01-01

The two, three and four nucleon potentials due to the exchange of pions can be accurately calculated by means of chiral symmetry. The comparison of the dynamical content of these potentials allow us to understand the geometrical origin of the hierarchy existing among them. (Author) [pt

Numerology in the second nuclear age

Energy Technology Data Exchange (ETDEWEB)

Krepon, M.

2009-07-01

The nuclear numbers game has changed. During the Cold War - the first nuclear age - deterrence strategists such as Henry Kissinger, Paul Nitze and Albert Wohlstetter claimed that the nuclear balance mattered, even at extraordinarily high numbers. ' As a result, one great irony of the first nuclear age was that the 'absolute' weapon still lent itself to the twin impulses of seeking advantage and seeking to avoid being placed at a disadvantage. This factor, among others, led to the production of approximately 125,000 U.S. and Soviet nuclear weapons during the Cold War. Nuclear 'numerology' during the Cold War centered around deployed capabilities in various categories, especially 'prompt hard-target kill' capabilities, missile 'throw-weight' and nuclear exchange ratios. By this musty logic, the United States now has more deterrence leverage against Russia than at any time since the Soviet nuclear build-up in the 1960's. This may help explain why the Kremlin feels so protective of its large stocks of tactical nuclear weapons, despite Washington's preferences. US leverage on Moscow also appears to be limited on other matters pertaining to the nuclear order, including ways to persuade North Korea and Iran to adhere to UN Security Council resolutions. Critics of the Obama administration ascribe this lack of suasion to 'soft' leadership that does not command respect or compel preferred behavior. But the 'hard' policies they preferred during the presidency of George W. Bush produced, to put it charitably, mixed results. Whatever value the nuclear numbers game had during the first nuclear age related primarily to contests played out with computers and hand calculators, not to real battlefields where nuclear-armed states fought with weaker foes, including contests between states with and without nuclear weapons. Numerical imbalances have been far more profound between the United States and China. For

Numerology in the second nuclear age

International Nuclear Information System (INIS)

Krepon, M.

2009-01-01

The nuclear numbers game has changed. During the Cold War - the first nuclear age - deterrence strategists such as Henry Kissinger, Paul Nitze and Albert Wohlstetter claimed that the nuclear balance mattered, even at extraordinarily high numbers. ' As a result, one great irony of the first nuclear age was that the 'absolute' weapon still lent itself to the twin impulses of seeking advantage and seeking to avoid being placed at a disadvantage. This factor, among others, led to the production of approximately 125,000 U.S. and Soviet nuclear weapons during the Cold War. Nuclear 'numerology' during the Cold War centered around deployed capabilities in various categories, especially 'prompt hard-target kill' capabilities, missile 'throw-weight' and nuclear exchange ratios. By this musty logic, the United States now has more deterrence leverage against Russia than at any time since the Soviet nuclear build-up in the 1960's. This may help explain why the Kremlin feels so protective of its large stocks of tactical nuclear weapons, despite Washington's preferences. US leverage on Moscow also appears to be limited on other matters pertaining to the nuclear order, including ways to persuade North Korea and Iran to adhere to UN Security Council resolutions. Critics of the Obama administration ascribe this lack of suasion to 'soft' leadership that does not command respect or compel preferred behavior. But the 'hard' policies they preferred during the presidency of George W. Bush produced, to put it charitably, mixed results. Whatever value the nuclear numbers game had during the first nuclear age related primarily to contests played out with computers and hand calculators, not to real battlefields where nuclear-armed states fought with weaker foes, including contests between states with and without nuclear weapons. Numerical imbalances have been far more profound between the United States and China. For financial and other reasons, Beijing did not play the nuclear numbers game

Heat exchangers for high-temperature thermodynamic cycles

International Nuclear Information System (INIS)

Fraas, A.P.

1975-01-01

The special requirements of heat exchangers for high temperature thermodynamic cycles are outlined and discussed with particular emphasis on cost and thermal stress problems. Typical approaches that have been taken to a comprehensive solution intended to meet all of the many boundary conditions are then considered by examining seven typical designs including liquid-to-liquid heat exchangers for nuclear plants, a heater for a closed cycle gas turbine coupled to a fluidized bed coal combustion chamber, steam generators for nuclear plants, a fossil fuel-fired potassium boiler, and a potassium condenser-steam generator. (auth)

Evaluation methodology for advance heat exchanger concepts using analytical hierarchy process

International Nuclear Information System (INIS)

Sabharwall, Piyush; Kim, Eung Soo; Patterson, Mike

2012-01-01

This study describes how the major alternatives and criteria being developed for the heat exchangers for next generation nuclear reactors are evaluated using the analytical hierarchy process (AHP). This evaluation was conducted as an aid in developing and selecting heat exchangers for integrating power production and process heat applications with next generation nuclear reactors. The basic setup for selecting the most appropriate heat exchanger option was established with evaluation goals, alternatives, and criteria. The two potential candidates explored in this study were shell-and-tube (helical coiled) and printed circuit heat exchangers. Based on study results, the shell-and-tube (helical coiled) heat exchanger is recommended for a demonstration reactor in the near term, mainly because of its reliability.

Nuclear Symbiosis - A Means to Achieve Sustainable Nuclear Growth while Limiting the Spread of Sensitive Nuclear Technology

International Nuclear Information System (INIS)

Shropshire, David

2009-01-01

Global growth of nuclear energy in the 21st century is creating new challenges to limit the spread of nuclear technology without hindering adoption in countries now considering nuclear power. Independent nuclear states desire autonomy over energy choices and seek energy independence. However, this independence comes with high costs for development of new indigenous fuel cycle capabilities. Nuclear supplier states and expert groups have proposed fuel supply assurance mechanisms such as fuel take-back services, international enrichment services and fuel banks in exchange for recipient state concessions on the development of sensitive technologies. Nuclear states are slow to accept any concessions to their rights under the Non-Proliferation Treaty. To date, decisions not to develop indigenous fuel cycle capabilities have been driven primarily by economics. However, additional incentives may be required to offset a nuclear state's perceived loss of energy independence. This paper proposes alternative economic development incentives that could help countries decide to forgo development of sensitive nuclear technologies. The incentives are created through a nuclear-centered industrial complex with 'symbiotic' links to indigenous economic opportunities. This paper also describes a practical tool called the 'Nuclear Materials Exchange' for identifying these opportunities.

Nuclear research reactor IEA-R1 heat exchanger inlet nozzle flow - a preliminary study

International Nuclear Information System (INIS)

Angelo, Gabriel; Andrade, Delvonei Alves de; Fainer, Gerson; Angelo, Edvaldo

2009-01-01

As a computational fluid mechanics training task, a preliminary model was developed. ANSYS-CFX R code was used in order to study the flow at the inlet nozzle of the heat exchanger of the primary circuit of the nuclear research reactor IEA-R1. The geometry of the inlet nozzle is basically compounded by a cylinder and two radial rings which are welded on the shell. When doing so there is an offset between the holes through the shell and the inlet nozzle. Since it is not standardized by TEMA, the inlet nozzle was chosen for a preliminary study of the flow. Results for the proposed model are presented and discussed. (author)

Metallic materials for heat exchanger components and highly stressed internal of HTR reactors for nuclear process heat generation

International Nuclear Information System (INIS)

1982-01-01

The programme was aimed at the development and improvement of materials for the high-temperature heat exchanger components of a process steam HTR. The materials must have high resistance to corrosion, i.e. carburisation and internal oxidation, and high long-term toughness over a wide range of temperatures. They must also meet the requirements set in the nuclear licensing procedure, i.e. resistance to cyclic stress and irradiation, non-destructive testing, etc. Initially, it was only intended to improve and qualify commercial alloys. Later on an alloy development programme was initiated in which new, non-commercial alloys were produced and modified for use in a nuclear process heat facility. Separate abstracts were prepared for 19 pays of this volume. (orig./IHOE) [de

Nuclear Data Unit correspondents for the exchange of nuclear data information

Energy Technology Data Exchange (ETDEWEB)

NONE

1968-04-15

This list serves as a basis for the distribution of documents originated by or for the International Nuclear Data Committee, and includes the names of all INDC members, liaison officers and correspondents of the Nuclear Data Unit. The IAEA Nuclear Data Unit tries to maintain this list up-to-date in order to facilitate an efficient interchange of information on nuclear data topics. The recipients of this list are encouraged to inform the Nuclear Data Unit of any corrections, additions and deletions deemed necessary. Because of the variety of document origins and functions, and the number of countries served by this list, each addressee is assigned a seven-letter distribution code, shown to the left of each name, which indicates the categories of documents he receives. The names appear under three categories, member states, international organizations and non-member states, and are listed in alphabetical order within each state or organization. The main list is followed by seven shorter lists, indicating the names of individuals in each distribution category, and the total number of individuals in each category.

Nuclear Data Unit correspondents for the exchange of nuclear data information

International Nuclear Information System (INIS)

1968-04-01

This list serves as a basis for the distribution of documents originated by or for the International Nuclear Data Committee, and includes the names of all INDC members, liaison officers and correspondents of the Nuclear Data Unit. The IAEA Nuclear Data Unit tries to maintain this list up-to-date in order to facilitate an efficient interchange of information on nuclear data topics. The recipients of this list are encouraged to inform the Nuclear Data Unit of any corrections, additions and deletions deemed necessary. Because of the variety of document origins and functions, and the number of countries served by this list, each addressee is assigned a seven-letter distribution code, shown to the left of each name, which indicates the categories of documents he receives. The names appear under three categories, member states, international organizations and non-member states, and are listed in alphabetical order within each state or organization. The main list is followed by seven shorter lists, indicating the names of individuals in each distribution category, and the total number of individuals in each category

Arrangement between the US Nuclear Regulatory Commission (USNRC) and the Belgian Government for Exchange of Technical Information in Regulatory Matters and in Cooperation in Safety Research and in Standards Development

International Nuclear Information System (INIS)

1978-01-01

This Arrangement was concluded on 6 June 1978 between the United States Nuclear Regulatory Commission and the Belgian Government for exchange of technical information in regulatory matters and in co-operation in safety research and in standards development. Both Parties agree to exchange, as available, technical information related to the regulation of safety and the environmental impact of designated nuclear energy facilities and to safety research of designated types of nuclear facilities. As regards co-operation in safety research, the execution of joint programmes and projects under which activities are divided between the two Parties will be agreed on a case by case basis. The Parties further agree to co-operate in the development of regulatory standards applicable to the designated nuclear facilities. The Arrangement is valid for 5 years and may be extended. (NEA) [fr

Nuclear structure theory

International Nuclear Information System (INIS)

French, J.B.; Koltun, D.S.

1989-01-01

This report summarizes progress during the past year in the following areas of research: Pion charge exchange reactions, including a theory of the contribution of pion absorption and correlated double scattering to double charge exchange, new coupled channel calculations for single and double charge exchange from 14 C. Nuclear inelastic scattering, using quark models to calculate nuclear structure functions, and test for sensitivity to the substructure of nucleons in nuclei. Fluctuation-free statistical spectroscopy including the theory and computer programs for interacting-particle densities, spin cutoff factors, occupancies, strength sums, and other expectation values. Proposed research for the coming year in each area is presented

Russian Federal Nuclear Center VNIIEF - possibilities of international cooperation

International Nuclear Information System (INIS)

Shaburov, V.M.; Mozharov, R.V.

2000-01-01

The Russian Federation Nuclear Center - the All-Russian Experimental Physics Research Institute (RFNC-AREPRI; VNIIEF) is a major scientific-technical center of Russia capable of solving the most difficult problems in the interests of defense, science and the national economy. There was a time when the RFNC-AREPRI played a decisive role in liquidating the U.S. monopoly on nuclear weapons and ensuring half a century of world civilization without global political and military conflicts. Today, RFNC-AREPRI specialists are entrusted with the mission of maintaining and perfecting Russia's nuclear shield that ensures its security and independence. As well as defense-oriented projects, the Institute is busy developing and implementing a number of projects in the most diverse fields of science and technology. At present, the Institute possesses an experimental and testing base that includes: a gas dynamic complex for testing manufactured products and explosives, irradiation facilities, nuclear reactors, laser systems, complexes for mechanical, temperature and climatic testing of specific manufactured products and instruments, and an aero-ballistic testing complex. The Institute's material base, with its mathematical support, is one of the most powerful in Russia. The RFNC-AREPRI employs about 20,000 workers, including 9,500 scientists and engineers. Today, the RFNC-AREPRI is engaged in activities in the following principal directions: - properties of material under extreme pressure and temperature; - gas dynamics; - nuclear physics; - radiation physics; - laser physics and equipment; - super-powerful magnetic fields; - high-temperature plasma physics; - development of physical models of complex physical processes and the creation of mathematical methodologies and software based on these models; - energy; - medicine; - ecology; - progressive technologies for various sectors of the economy. International cooperation of the RFNC-AREPRI is reviewed. (authors)

Inorganic ion exchangers in industrial and nuclear waste treatment

International Nuclear Information System (INIS)

Manosso, Helena C.; Forbicini, Christina A.L.G.O.

2000-01-01

Zirconium and titanium phosphates have been used as inorganic ion exchangers for many years. Their characteristics, as high exchange capacity and ionizing and oxidizing reagents resistance, among others, have made them suitable for the treatment of wastes, mostly the radioactive ones. Due to its granulometry, zirconium phosphate (Zr P) must be prepared on an inert support, or it can be synthesized , as well as titanium phosphate, with modifiers, to promote better distribution of the exchanger over the support surface and to enlarge the cavities of their crystal lattice. The prepared exchangers were analyzed by electronic sweep microscopy. The studies on cesium and chromium sorption were made by using radioactive tracer technique, with Cs-134 and Cr-51 radioisotopes. The sorption of cesium in Zr P and Ti P was about 95%, but chromium showed very low sorption in the studied conditions, indicating the necessity of more experiments varying pH and temperature of the solutions. (author)

Eddy current automatic inspection of heat exchangers in nuclear power stations

International Nuclear Information System (INIS)

Cazal, M.; Scopelliti, J.D.; Mendez, J.

1997-01-01

This presentation describes the eddy current tube inspection techniques for heavy heat exchangers in nuclear power stations. The purpose of these eddy current tests, is first to determine the integrity of the heat exchanger tubes, and to characterize the related types of defects in each case following to their analysis and cause determination and subsequent inspection planning. This task requires a group highly qualified personnel with high tech automate equipment. The organization of the group required a correct function and task assignment in order to achieve efficiency in scheduling, with simultaneous inspection to different components in a continuous base and uninterruptedly. A lead specialist is in charge of the group, which is set up by several shift supervisors, a qualified tele manipulator installation crew a number of qualified tele manipulator operators, and the specialist for data acquisition and certified eddy current signal evaluators plus some other support technicians and administrations helpers. In order to comply with inspection requirements, a bunch of technical procedures had to be developed. The following equipment is available nowadays: Zetec SM-13, SM-23 and SM-22 tele manipulators for inspection probes positioning, with different shapes and configuration (rotating probes, flexible probes for U-Bends, and magnetic saturation probes endowed with their own driving units) and remote data acquisition units identified as MIZ-18 A and MIZ-30, which are remotely operated from a mobile lab installed in a trailer, outside the reactor building. The available equipment allows a simultaneous inspection of three different plant components (two steam generators and a moderator heat exchanger). We are also in a position of performing eddy current tube inspection in more than a NSP at the same time. The Zetec Eddynet software is used in the manipulator operation and for the data acquisition and defect evaluation. This software operates within Windows

Advances in processing technologies for titanium heat exchanger tubes of fossil and nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Likhareva, T P; Tchizhik, A A; Chavchanidze, N N [Polzanov Central Boiler and Turbine Institute, St. Petersburg (Russian Federation)

1999-12-31

The advances in processing technologies for titanium heat exchangers with rolled and welded tubes of fossil and nuclear power plants in Russia are presented. The special methodology of investigations with constant small strain rate have been used to study the effects of mixed corrosion and creep processes in condensers cooled by sea or synthetic sea waters. The results of corrosion creep tests and K1scc calculations are given. The Russian science activities concerning condensers manufactured from titanium show the possibilities for designing structures with very high level service reliability in different corrosion aggressive mediums with high total salt, Cl-ion and oxygen contents. (orig.)

Advances in processing technologies for titanium heat exchanger tubes of fossil and nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Likhareva, T.P.; Tchizhik, A.A.; Chavchanidze, N.N. [Polzanov Central Boiler and Turbine Institute, St. Petersburg (Russian Federation)

1998-12-31

The advances in processing technologies for titanium heat exchangers with rolled and welded tubes of fossil and nuclear power plants in Russia are presented. The special methodology of investigations with constant small strain rate have been used to study the effects of mixed corrosion and creep processes in condensers cooled by sea or synthetic sea waters. The results of corrosion creep tests and K1scc calculations are given. The Russian science activities concerning condensers manufactured from titanium show the possibilities for designing structures with very high level service reliability in different corrosion aggressive mediums with high total salt, Cl-ion and oxygen contents. (orig.)

American Nuclear Society exchanges of information

International Nuclear Information System (INIS)

Du Temple, O.J.

2000-01-01

Many are familiar with the technical journals and other publications that American Nuclear Society (ANS) members receive. However, there is a whole series of documents that is helpful to any nuclear society group for a modest fee or no fee. The author is referring to documents such as the ANS Bylaws and Rules, which have been made available to almost every existing nuclear society in the world. He remembers working with groups from Russia, Europe, China, Japan, Brazil, France, Germany, and others when they sought the experience of ANS in establishing a society. Financial planning guides are available for meetings, international conferences, technical expositions, and teacher workshops. Periodically, the ANS publishes position papers on the uses and handling of fuel materials and other publications helpful to public relations and teacher training courses. A few have had distributions in the hundreds of thousands, and one went as high as 750,000. Some of these have been translated in part into Spanish, French, Portuguese, and Japanese. Nuclear Standards are developed by a series of ANS committees consisting of about 1000 experts--the largest technical operation of ANS. Buyers guides and directories are very helpful in promoting the commerce in the nuclear industry. The Utility Directory covers utilities all over the globe. Radwaste Solutions, the new name for the former Radwaste Magazine, covers the efforts made by all sectors--private, government, and utility--to deal with radioactive waste. In the author's opinion, the one area in which all societies are weak is in interfacing with the International Atomic Energy Agency (IAEA). Since his retirement 9 yr ago, he has become much more aware of the IAEA as a news and technical information source. The ANS is trying to be more aware of what the IAEA is doing for everyone

Ion-exchange properties of microporous tungstates: novel adsorbents for nuclear waste management applications

International Nuclear Information System (INIS)

Griffith, C.S.; Luca, V.; Eddowes, R.C.; Keegan, E.A.; Scales, N.

2003-01-01

A hydrothermally prepared tungsten oxide-based phase, ATS-1 (ANSTO Tungstate Sorbent), of nominal composition, Na 0.3 Mo 0.1 W 0.9O3 .χH 2 O, has been shown to display promising selectivity for both Cs + and Sr 2+ cations from acidic simulant, indicative of the Intermediate Level Liquid Waste (ILLW) produced from 99 Mo radioisotope production at the ANSTO site. The development of an inorganic ion-exchanger that displays such selectivity for both Cs + and Sr 2+ in acidic solutions has previously eluded researchers in the field of inorganic ion-exchangers. The ATS-1 adsorbent also displays exquisite selectivity for lead (and polonium) in low to high acidity solutions, and as such is being further investigated as a method to reduce the radiological hazard from 210 Pb and 210 Po during the processing of uranium ore bodies. The adsorption of Cs + , Sr 2+ and Pb 2+ cations by ATS-1 has been extensively investigated with respect to the kinetics of adsorption, capacity and the effect of competing cations viz. Na + , K + . The ATS-1 adsorbent has also been successfully granulated with an inert, organic matrix, which has consequently allowed the study of cation adsorption using more application-based, column separations. The results of these investigations suggest that these materials have potential application in several nuclear waste management issues in Australia at the present

Nuclear forces

International Nuclear Information System (INIS)

Holinde, K.

1990-01-01

In this paper the present status of the meson theory of nuclear forces is reviewed. After some introductory remarks about the relevance of the meson exchange concept in the era of QCD and the empirical features of the NN interaction, the exciting history of nuclear forces is briefly outlined. In the main part, the author gives the basic physical ideas and sketch the derivation of the one-boson-exchange model of the nuclear force, in the Feynman approach. Secondly we describe, in a qualitative way, various necessary extensions, leading to the Bonn model of the N interaction. Finally, points to some interesting pen questions connected with the extended quark structure of the hadrons, which are topics of current research activity

ASME code considerations for the compact heat exchanger

Energy Technology Data Exchange (ETDEWEB)

Nestell, James [MPR Associates Inc., Alexandria, VA (United States); Sham, Sam [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-08-31

The mission of the U.S. Department of Energy (DOE), Office of Nuclear Energy is to advance nuclear power in order to meet the nation's energy, environmental, and energy security needs. Advanced high temperature reactor systems such as sodium fast reactors and high and very high temperature gas-cooled reactors are being considered for the next generation of nuclear reactor plant designs. The coolants for these high temperature reactor systems include liquid sodium and helium gas. Supercritical carbon dioxide (sCO₂), a fluid at a temperature and pressure above the supercritical point of CO₂, is currently being investigated by DOE as a working fluid for a nuclear or fossil-heated recompression closed Brayton cycle energy conversion system that operates at 550°C (1022°F) at 200 bar (2900 psi). Higher operating temperatures are envisioned in future developments. All of these design concepts require a highly effective heat exchanger that transfers heat from the nuclear or chemical reactor to the chemical process fluid or the to the power cycle. In the nuclear designs described above, heat is transferred from the primary to the secondary loop via an intermediate heat exchanger (IHX) and then from the intermediate loop to either a working process or a power cycle via a secondary heat exchanger (SHX). The IHX is a component in the primary coolant loop which will be classified as "safety related." The intermediate loop will likely be classified as "not safety related but important to safety." These safety classifications have a direct bearing on heat exchanger design approaches for the IHX and SHX. The very high temperatures being considered for the VHTR will require the use of very high temperature alloys for the IHX and SHX. Material cost considerations alone will dictate that the IHX and SHX be highly effective; that is, provide high heat transfer area in a small volume. This feature must be accompanied by low pressure drop and mechanical reliability and

Nuclear reactors

International Nuclear Information System (INIS)

Humphreys, P.; Davidson, D.F.; Thatcher, G.

1980-01-01

The cooling system of a liquid metal cooled fast breeder nuclear reactor of the pool kind is described. It has an intermediate heat exchange module comprising a tube-in-shell heat exchanger and an electromagnetic flow coupler in the base region of the module. Primary coolant is flowed through the heat exchanger being driven by electromagnetic interaction with secondary liquid metal coolant flow effected by a mechanical pump. (author)

Nuclear reactor

International Nuclear Information System (INIS)

Batheja, P.; Huber, R.; Rau, P.

1985-01-01

Particularly for nuclear reactors of small output, the reactor pressure vessel contains at least two heat exchangers, which have coolant flowing through them in a circuit through the reactor core. The circuit of at least one heat exchanger is controlled by a slide valve, so that even for low drive forces, particularly in natural circulation, the required even loading of the heat exchanger is possible. (orig./HP) [de

Study of nuclear medium effects on the effective interaction based on the one-boson exchange model

International Nuclear Information System (INIS)

Nakayama, K.

1985-02-01

In this work, starting from a realistic nucleon-nucleon interaction based on the one-boson exchange model for the nuclear force, we attempted a microscopic derivation of the effective interaction which may be appropriate for nuclear structure as well as for nucleon-nucleus scattering problems. Short-range correlations and medium polarization as well as relativistic effects on both particle-hole and Δ-hole interactions have been investigated. For the nucleon-nucleon case short-range correlations are basically restricted to S-states and affect mainly the central components of the effective interaction. In contrast, the Δ-nucleon interaction is essentially unaffected by short-range correlations due to the Pauli principle restrictions and the momentum mismatch between the central components of the correlation operator and the tensor component of the bare transition potential. Based on these analyses it is shown that short-range correlation effects can be summarized in a very simple correlation operator. (orig./HSI)

Coolant clean up system in nuclear reactor

International Nuclear Information System (INIS)

Tajima, Fumio; Iwami, Hiroshi.

1981-01-01

Purpose: To decrease the amount of main steams and improve the plant heat efficiency by the use of condensated water as coolants for not-regenerative heat exchangers in a coolant clean up system of a nuclear reactor. Constitution: In a coolant clean up system of a nuclear reactor, a portion of condensates is transferred to the shell of a non-regenerative heat exchanger by way of a condensate pump for non-regenerative heat exchanger through a branched pipeway provided to the outlet of a condensate desalter for using the condensates as the coolants for the shell of the heat exchanger and the condensates are then returned to the inlet of a feedwater heater after the heat exchange. The branched flow rate of the condensates is controlled by the flow rate control valve mounted in the pipeway. Condensates passed through the heat exchanger and the condensates not passed through the heat exchanger are mixed and heated in a heater and then fed to the nuclear reactor. In a case where no feedwater is necessary to the nuclear reactor such as upon shutdown of the reactor, the condensates are returned by way of feedwater bypass pipeway to the condensator. By the use of the condensates as the coolants for the heat exchanger, the main steam loss can be decreased and the thermal load for the auxiliary coolant facility can be reduced. (Kawakami, Y.)

Method of solidifying radioactive ion exchange resin

International Nuclear Information System (INIS)

Minami, Yuji; Tomita, Toshihide

1989-01-01

Spent anion exchange resin formed in nuclear power plants, etc. generally catch only a portion of anions in view of the ion exchange resins capacity and most of the anions are sent while possessing activities to radioactive waste processing systems. Then, the anion exchange resins increase the specific gravity by the capture of the anions. Accordingly, anions are caused to be captured on the anion exchange resin wastes such that the specific gravity of the anion exchange resin wastes is greater than that of the thermosetting resins to be mixed. This enables satisfactory mixing with the thermosetting resins and, in addition, enables to form integral solidification products in which anion exchange resins and cation exchange resins are not locallized separately and which are homogenous and free from cracks. (T.M.)

Low-temperature nuclear heat applications: Nuclear power plants for district heating

International Nuclear Information System (INIS)

1987-08-01

The IAEA reflected the needs of its Member States for the exchange of information in the field of nuclear heat application already in the late 1970s. In the early 1980s, some Member States showed their interest in the use of heat from electricity producing nuclear power plants and in the development of nuclear heating plants. Accordingly, a technical committee meeting with a workshop was organized in 1983 to review the status of nuclear heat application which confirmed both the progress made in this field and the renewed interest of Member States in an active exchange of information about this subject. In 1985 an Advisory Group summarized the Potential of Low-Temperature Nuclear Heat Application; the relevant Technical Document reviewing the situation in the IAEA's Member States was issued in 1986 (IAEA-TECDOC-397). Programme plans were made for 1986-88 and the IAEA was asked to promote the exchange of information, with specific emphasis on the design criteria, operating experience, safety requirements and specifications for heat-only reactors, co-generation plants and power plants adapted for heat application. Because of a growing interest of the IAEA's Member States about nuclear heat employment in the district heating domaine, an Advisory Group meeting was organized by the IAEA on ''Low-Temperature Nuclear Heat Application: Nuclear Power Plants for District Heating'' in Prague, Czechoslovakia in June 1986. The information gained up to 1986 and discussed during this meeting is embodied in the present Technical Document. 22 figs, 11 tabs

Memorandum of understanding between the Government of the Kingdom of Norway and the Government of the Kingdom of the Netherlands on early notification of a nuclear accident and exchange of safety related information concerning the operation and management of nuclear facilities

International Nuclear Information System (INIS)

1989-01-01

This Agreement was concluded in implementation of the IAEA 1986 Convention on Early Notification of a Nuclear Accident. Both Governments undertake to notify each other forthwith of any abnormal radiation levels in their respective countries. They will exchange safety related information on nuclear facilities and inform each other of measures to protect the population and the environment. (NEA)

Memorandum of understanding between the Government of the Kingdom of Norway and the Government of the Kingdom of the Netherlands on early notification of a nuclear accident and exchange of safety related information concerning the operation and management of nuclear facilities

Energy Technology Data Exchange (ETDEWEB)

1989-04-18

This Agreement was concluded in implementation of the IAEA 1986 Convention on Early Notification of a Nuclear Accident. Both Governments undertake to notify each other forthwith of any abnormal radiation levels in their respective countries. They will exchange safety related information on nuclear facilities and inform each other of measures to protect the population and the environment. (NEA).

Quantification of exchangeable and non-exchangeable organically bound tritium (OBT) in vegetation.

Science.gov (United States)

Kim, S B; Korolevych, V

2013-04-01

The objective of this study is to quantify the relative amounts of exchangeable organically bound tritium (OBT) and non-exchangeable OBT in various vegetables. A garden plot at Perch Lake, where tritium levels are slightly elevated due to releases of tritium from a nearby nuclear waste management area and Chalk River Laboratories (CRL) operations, was used to cultivate a variety of vegetables. Five different kinds of vegetables (lettuce, cabbage, tomato, radish and beet) were studied. Exchangeable OBT behaves like tritium in tissue free water in living organisms and, based on past measurements, accounts for about 20% of the total tritium in dehydrated organic materials. In this study, the percentage of the exchangeable OBT was determined to range from 20% to 57% and was found to depend on the type of vegetables as well as the sequence of the plants exposure to HTO. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

China

International Nuclear Information System (INIS)

Segal, G.

1991-01-01

This paper reports on the reason for China's future nuclear policy. First, assuming a continued decline in superpower influence, China's focus will be on regional issues. The policies of Japan, the NICs and other Chinese neighbors will be more relevant than those of the superpowers. Second, Chinese domestic politics will have to resume the road to reform. A more unstable and suspicious Chinese leadership will perceive a more hostile and unstable world. Even when China was on the path to reform, its foreign relations were not always peaceful. However, it would be wrong to suggest that even a more xenophobic and unstable Chinese leadership would necessarily expand China's nuclear capability or lead China into a major war. Even at the height of the Cultural Revolution, Chinese foreign policy was careful, nuclear proliferation was avoided and crises were well-managed. Still China's basic domestic and foreign policy needs will likely remain unfulfilled for the foreseeable future. Furthermore, although the East Asian balance of power may not appear to be particularly dangerous at present, there is enough uncertainty to ensure that China remains a nuclear power and a maverick one at that at least in the near term

Exchange of Notes constituting an Agreement between the Government of Australia and the Government of the United States of America to bring International Obligation Exchanges under the Coverage of the Agreement concerning Peaceful Uses of Nuclear Energy, and Agreed Minute, of 5 July 1979

International Nuclear Information System (INIS)

1991-01-01

This Exchange of Notes, which entered into force on 16 December 1991, refers to the safeguards obligations of both Contracting Parties under their Agreement on the Peaceful Uses of Nuclear Energy and the Exchange of Notes of 2 August 1985 concerning the duration of safeguards. Both Parties agree that the Agreement will apply to the quantity of materials to which either Party, at the request of the other Party, has consented that it should apply as part of the arrangement to exchange safeguards obligations, or that it should no longer apply. (NEA)

Composite inorganic ion-exchangers and their applications

International Nuclear Information System (INIS)

Sebesta, F.; John, J.; Motl, A.

1998-01-01

Composite inorganic ion exchangers are described containing modified polyacrylonitrile as the binding polymer. An overview of existing composite ion exchangers is presented, and the universality and assets of the developed procedure of treatment of inorganic ion exchanger powders are highlighted. Examples of applicability of the ion exchangers to the separation and concentration of radionuclides include in particular: wastes from the operation of nuclear power plants, contaminated surface waters and ground water, high level radioactive wastes from spent fuel reprocessing, and wastewaters from uranium ore mining and milling. In addition, composite ion exchangers find use in the monitoring of contamination of the hydrosphere and the environment and in the investigation of radionuclide migration in surface waters and ground water

Multiprocessor shared-memory information exchange

International Nuclear Information System (INIS)

Santoline, L.L.; Bowers, M.D.; Crew, A.W.; Roslund, C.J.; Ghrist, W.D. III

1989-01-01

In distributed microprocessor-based instrumentation and control systems, the inter-and intra-subsystem communication requirements ultimately form the basis for the overall system architecture. This paper describes a software protocol which addresses the intra-subsystem communications problem. Specifically the protocol allows for multiple processors to exchange information via a shared-memory interface. The authors primary goal is to provide a reliable means for information to be exchanged between central application processor boards (masters) and dedicated function processor boards (slaves) in a single computer chassis. The resultant Multiprocessor Shared-Memory Information Exchange (MSMIE) protocol, a standard master-slave shared-memory interface suitable for use in nuclear safety systems, is designed to pass unidirectional buffers of information between the processors while providing a minimum, deterministic cycle time for this data exchange

Pressure-assisted cold denaturation of hen egg white lysozyme: the influence of co-solvents probed by hydrogen exchange nuclear magnetic resonance.

Science.gov (United States)

Vogtt, K; Winter, R

2005-08-01

COSY proton nuclear magnetic resonance was used to measure the exchange rates of amide protons of hen egg white lysozyme (HEWL) in the pressure-assisted cold-denatured state and in the heat-denatured state. After dissolving lysozyme in deuterium oxide buffer, labile protons exchange for deuterons in such a way that exposed protons are substituted rapidly, whereas "protected" protons within structured parts of the protein are substituted slowly. The exchange rates k obs were determined for HEWL under heat treatment (80 degrees C) and under high pressure conditions at low temperature (3.75 kbar, -13 degrees C). Moreover, the influence of co-solvents (sorbitol, urea) on the exchange rate was examined under pressure-assisted cold denaturation conditions, and the corresponding protection factors, P, were determined. The exchange kinetics upon heat treatment was found to be a two-step process with initial slow exchange followed by a fast one, showing residual protection in the slow-exchange state and P-factors in the random-coil-like range for the final temperature-denatured state. Addition of sorbitol (500 mM) led to an increase of P-factors for the pressure-assisted cold denatured state, but not for the heat-denatured state. The presence of 2 M urea resulted in a drastic decrease of the P-factors of the pressure-assisted cold denatured state. For both types of co-solvents, the effect they exert appears to be cooperative, i.e., no particular regions within the protein can be identified with significantly diverse changes of P-factors.

Pressure-assisted cold denaturation of hen egg white lysozyme: the influence of co-solvents probed by hydrogen exchange nuclear magnetic resonance

Directory of Open Access Journals (Sweden)

K. Vogtt

2005-08-01

Full Text Available COSY proton nuclear magnetic resonance was used to measure the exchange rates of amide protons of hen egg white lysozyme (HEWL in the pressure-assisted cold-denatured state and in the heat-denatured state. After dissolving lysozyme in deuterium oxide buffer, labile protons exchange for deuterons in such a way that exposed protons are substituted rapidly, whereas "protected" protons within structured parts of the protein are substituted slowly. The exchange rates k obs were determined for HEWL under heat treatment (80ºC and under high pressure conditions at low temperature (3.75 kbar, -13ºC. Moreover, the influence of co-solvents (sorbitol, urea on the exchange rate was examined under pressure-assisted cold denaturation conditions, and the corresponding protection factors, P, were determined. The exchange kinetics upon heat treatment was found to be a two-step process with initial slow exchange followed by a fast one, showing residual protection in the slow-exchange state and P-factors in the random-coil-like range for the final temperature-denatured state. Addition of sorbitol (500 mM led to an increase of P-factors for the pressure-assisted cold denatured state, but not for the heat-denatured state. The presence of 2 M urea resulted in a drastic decrease of the P-factors of the pressure-assisted cold denatured state. For both types of co-solvents, the effect they exert appears to be cooperative, i.e., no particular regions within the protein can be identified with significantly diverse changes of P-factors.

Nuclear magnetic resonance line-shape analysis and determination of exchange rates

International Nuclear Information System (INIS)

Rao, B.D.

1989-01-01

The fact that chemical exchange processes occur at rates that cover a broad range and produce readily detectable effects on the spectrum is one of the attractive features of high-resolution NMR. The description of these line shapes in the presence of spin-spin coupling requires the density matrix theory which is rather complex. Analysis of the line shapes usually needs computer simulations and is capable of providing reliable information on the exchange rates as well as spectral parameters in the absence of exchange. Simplified procedures, ignoring spin-spin coupling, often result in deviations in these exchange and spectral parameters determined. A step-by-step procedure is detailed in this chapter for setting up the matrices required for computing the line shapes of exchanges involving weakly coupled spin systems on the basis of the density matrix theory without the need for a detailed understanding of the theory. A knowledge of the energy level structure and allowed transitions in the NMR spectra of the individual weakly coupled spin systems is all that is required. The procedure is amenable to numerical computation. The group of illustrative examples chosen to demonstrate the development of the computational tools cover some of the commonly encountered cases of exchange from simple systems to rather complex ones. Such exchanges occur frequently in biological molecules, especially those involving enzyme-substrate complexes. In cases where the experimental line shapes are obtained with respectable precision, and the relevant exchange processes are unambiguously identifiable, the computer simulation method of line-shape analysis is capable of providing useful and incisive information. The example of the 31P exchanges in the adenylate kinase is illustrative of this point

Diamond wire cutting of heat exchangers

International Nuclear Information System (INIS)

Beckman, T.R.; Bjerler, J.

1991-01-01

With the change-out of equipment at nuclear power plants comes large quantities of low level contaminated metallic waste. Of particular concern are large heat exchangers, preheaters and steam generators. These bulky items consume huge volumes of burial space. The need for volume reduction and recycling of these metals has created new demands for 'how' to cut heat exchangers into useful sizes for decontamination, melting or compaction. This paper reviews the cutting solution provided by a diamond wire system, with particular regard for cutting of a Ringhals Preheater Bundle at Studsvik Nuclear in 1989. The background of diamond wire sawing is discussed and basic components of wire sawing are explained. Other examples of wire cutting decommissioned components are also given. (author)

Single- and double-charge exchange at low pion energies

International Nuclear Information System (INIS)

Baer, H.W.

1991-01-01

A review is given of pion single- and double-charge exchange reactions at incident energies of 25 to 65 MeV leading to isobaric analog states, and in the case of double-charge exchange leading to the ground state of the residual nucleus. The crucial role of the higher nuclear transparency at low pion energies for the analysis of the data in terms of single and double scattering is demonstrated. The large effects on double-charge exchange produced by the spatial correlations in nuclear wave functions are evident. The data on 1f 7/2 nuclei at 35 MeV are used to establish the general validity of a shell-model-based two-amplitude model for these transitions. Recent measurements of the energy dependence between 25 and 65 MeV of double-charge exchange cross sections at forward angles are presented and discussed. 33 refs., 19 figs

Application of transient analysis methodology to heat exchanger performance monitoring

International Nuclear Information System (INIS)

Rampall, I.; Soler, A.I.; Singh, K.P.; Scott, B.H.

1994-01-01

A transient testing technique is developed to evaluate the thermal performance of industrial scale heat exchangers. A Galerkin-based numerical method with a choice of spectral basis elements to account for spatial temperature variations in heat exchangers is developed to solve the transient heat exchanger model equations. Testing a heat exchanger in the transient state may be the only viable alternative where conventional steady state testing procedures are impossible or infeasible. For example, this methodology is particularly suited to the determination of fouling levels in component cooling water system heat exchangers in nuclear power plants. The heat load on these so-called component coolers under steady state conditions is too small to permit meaningful testing. An adequate heat load develops immediately after a reactor shutdown when the exchanger inlet temperatures are highly time-dependent. The application of the analysis methodology is illustrated herein with reference to an in-situ transient testing carried out at a nuclear power plant. The method, however, is applicable to any transient testing application

A concept of PWR using plate and shell heat exchangers

International Nuclear Information System (INIS)

Freire, Luciano Ondir; Andrade, Delvonei Alves de

2015-01-01

In previous work it was verified the physical possibility of using plate and shell heat exchangers for steam generation in a PWR for merchant ships. This work studies the possibility of using GESMEX commercial of the shelf plate and shell heat exchanger of series XPS. It was found it is feasible for this type of heat exchanger to meet operational and accidental requirements for steam generation in PWR. Additionally, it is proposed an arrangement of such heat exchangers inside the reactor pressure vessel. Such arrangement may avoid ANSI/ANS51.1 nuclear class I requirements on those heat exchangers because they are contained in the reactor coolant pressure barrier and play no role in accidental scenarios. Additionally, those plates work under compression, preventing the risk of rupture. Being considered non-nuclear safety, having a modular architecture and working under compression may turn such architectural choice a must to meet safety objectives with improved economics. (author)

A concept of PWR using plate and shell heat exchangers

Energy Technology Data Exchange (ETDEWEB)

Freire, Luciano Ondir; Andrade, Delvonei Alves de, E-mail: luciano.ondir@gmail.com, E-mail: delvonei@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

In previous work it was verified the physical possibility of using plate and shell heat exchangers for steam generation in a PWR for merchant ships. This work studies the possibility of using GESMEX commercial of the shelf plate and shell heat exchanger of series XPS. It was found it is feasible for this type of heat exchanger to meet operational and accidental requirements for steam generation in PWR. Additionally, it is proposed an arrangement of such heat exchangers inside the reactor pressure vessel. Such arrangement may avoid ANSI/ANS51.1 nuclear class I requirements on those heat exchangers because they are contained in the reactor coolant pressure barrier and play no role in accidental scenarios. Additionally, those plates work under compression, preventing the risk of rupture. Being considered non-nuclear safety, having a modular architecture and working under compression may turn such architectural choice a must to meet safety objectives with improved economics. (author)

Nuclear structure theory

International Nuclear Information System (INIS)

French, J.B.; Koltun, D.S.

1990-06-01

This report summarizes progress during the past ten months in the following areas of research: pion double charge exchange reactions, including a theory of the isotensor term in the pion-nucleus optical potential, and a study of meson exchange contributions to the reactions at low energies. Nuclear inelastic scattering, using quark models to calculate nuclear structure functions, and to test for sensitivity to the substructure of nucleons in nuclei. Fluctuation-free statistical spectroscopy including the theory and computer programs for interacting-particle densities, spin cutoff factors, occupancies, strength sums, and other expectation values

The Hatch-Smolensk exchange

International Nuclear Information System (INIS)

Sproles, A.

1993-01-01

During summer 1992, the World Association of Nuclear Operators (WANO) sponsored an exchange visit between Georgia Power Company's Edwin I. Hatch nuclear plant, a two-unit boiling water reactor site, and the Smolensk atomic energy station, a three-unit RBMK (graphite-moderated and light-water-cooled) plant located 350 km west of Moscow, in Desnogorsk, Russia. The Plant Hatch team included Glenn Goode, manager of engineering support; Curtis Coggin, manager of training and emergency preparedness; Wayne Kirkley, manager of health physics and chemistry; John Lewis, manager of operations; Ray Baker, coordinator of nuclear fuels and contracts; and Bruce McLeod, manager of nuclear maintenance support. Also traveling with the team was Jerald Towgood, of WANO's Atlanta Centre. The Hatch team visited the Smolensk plant during the week of July 27, 1992

Inorganic anion exchangers for the treatment of radioactive wastes

International Nuclear Information System (INIS)

Dyer, A.; Jamil, M.A.

1987-07-01

Inorganic anion exchangers are evaluated for Tc, I and S isotope removal from aqueous nuclear waste streams. Chemical, thermal, and radiation stabilities were examined. Selected exchangers were examined in detail for their selectivities, kinetics and mechanism of the sorption process (especially in NO 3 - , OH - and BO 3 - environments). Cement encapsulation and leaching experiments were made on the exchangers showing most promise for 'radwaste' treatment. (author)

Double Charge Exchange Reactions and Double Beta Decay

Science.gov (United States)

Auerbach, N.

2018-05-01

The subject of this presentation is at the forefront of nuclear physics, namely double beta decay. In particular one is most interested in the neutrinoless process of double beta decay, when the decay proceeds without the emission of two neutrinos. The observation of such decay would mean that the lepton conservation symmetry is violated and that the neutrinos are of Majorana type, meaning that they are their own anti-particles. The life time of this process has two unknowns, the mass of the neutrino and the nuclear matrix element. Determining the nuclear matrix element and knowing the cross-section well will set limits on the neutrino mass. There is a concentrated effort among the nuclear physics community to calculate this matrix element. Usually these matrix elements are a very small part of the total strength of the transition operators involved in the process. There is no simple way to “calibrate” the nuclear double beta decay matrix element. The double beta decay is a double charge exchange process, therefore it is proposed that double charge exchange reactions using ion projectiles on nuclei that are candidates for double beta decay, will provide additional necessary information about the nuclear matrix elements.

Application of ion exchange in liquid radioactive waste management of nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Pal, Puskar; Chopra, S K; Sharma, P D [Nuclear Power Corporation, Bhabha Atomic Research Centre, Mumbai (India)

1994-06-01

The operation of nuclear power plants would necessarily result in generation of gaseous, liquid and solid radioactive wastes. The wastes are treated/conditioned to ensure that the permissible discharge limits laid down by Atomic Energy Regulatory Board of India are complied with. The wastes are segregated on activity levels, types of radioisotopes present and chemical nature of liquid streams. The basic philosophy of various treatment techniques is to concentrate and contain as much activity as possible. It is of utmost importance that the wastes are effectively treated by proven methods/processes. The radiochemical nature of waste generated is one of the parameters to select a treatment/conditioning method. The paper presents an outline of various processes adopted for treatment of liquid waste and ion exchange processes, their application in liquid waste management in detail. Projected quantities of liquid wastes for the current designs are included. (author). 2 tabs.

Effects of ionizing radiation on modern ion exchange materials

International Nuclear Information System (INIS)

Marsh, S.F.; Pillay, K.K.S.

1993-10-01

We review published studies of the effects of ionizing radiation on ion exchange materials, emphasizing those published in recent years. A brief overview is followed by a more detailed examination of recent developments. Our review includes styrene/divinylbenzene copolymers with cation-exchange or anion-exchange functional groups, polyvinylpyridine anion exchangers, chelating resins, multifunctional resins, and inorganic exchangers. In general, strong-acid cation exchange resins are more resistant to radiation than are strong-base anion exchange resins, and polyvinylpyridine resins are more resistant than polystyrene resins. Cross-linkage, salt form, moisture content, and the surrounding medium all affect the radiation stability of a specific exchanger. Inorganic exchangers usually, but not always, exhibit high radiation resistance. Liquid ion exchangers, which have been used so extensively in nuclear processing applications, also are included

Development of heat resistant ion exchange resin. First Report

International Nuclear Information System (INIS)

Onozuka, Teruo; Shindo, Manabu

1995-01-01

In nuclear power stations, as a means of maintaining the soundness of nuclear reactors, the cleaning of reactor cooling water has been carried out. But as for the ion exchange resin which is used as the cleaning agent in the filtrating and desalting facility in reactor water cleaning system, since the heat resistance is low, high temperature reactor water is cooled once and cleaned, therefore large heat loss occurs. If the cleaning can be done at higher temperature, the reduction of heat loss and compact cleaning facilities become possible. In this study, a new ion exchange resin having superior heat resistance has been developed, and the results of the test of evaluating the performance of the developed ion exchange resin are reported. The heat loss in reactor water cleaning system, the heat deterioration of conventional ion exchange resin, and the development of the anion exchange resin of alkyl spacer type are described. The outline of the performance evaluation test, the experimental method, and the results of the heat resistance, ion exchange characteristics and so on of C4 resin are reported. The with standable temperature of the developed anion exchange resin was estimated as 80 - 90degC. The ion exchange performance at 95degC of this resin did not change from that at low temperature in chloride ions and silica, and was equivalent to that of existing anion exchange resin. (K.I.)

Development of heat resistant ion exchange resin. First Report

Energy Technology Data Exchange (ETDEWEB)

Onozuka, Teruo; Shindo, Manabu [Tohoku Electric Power Co., Inc., Sendai (Japan)

1995-01-01

In nuclear power stations, as a means of maintaining the soundness of nuclear reactors, the cleaning of reactor cooling water has been carried out. But as for the ion exchange resin which is used as the cleaning agent in the filtrating and desalting facility in reactor water cleaning system, since the heat resistance is low, high temperature reactor water is cooled once and cleaned, therefore large heat loss occurs. If the cleaning can be done at higher temperature, the reduction of heat loss and compact cleaning facilities become possible. In this study, a new ion exchange resin having superior heat resistance has been developed, and the results of the test of evaluating the performance of the developed ion exchange resin are reported. The heat loss in reactor water cleaning system, the heat deterioration of conventional ion exchange resin, and the development of the anion exchange resin of alkyl spacer type are described. The outline of the performance evaluation test, the experimental method, and the results of the heat resistance, ion exchange characteristics and so on of C4 resin are reported. The with standable temperature of the developed anion exchange resin was estimated as 80 - 90degC. The ion exchange performance at 95degC of this resin did not change from that at low temperature in chloride ions and silica, and was equivalent to that of existing anion exchange resin. (K.I.).

Exchange current contributions to quasi-elastic electron scattering

International Nuclear Information System (INIS)

Conte, J.S. Jr.

1981-01-01

Because electromagnetic interactions are weak and well understood, inelastic electron scattering has been very useful in elucidating aspects of nuclear structure. In the region of large electron energy loss, an extremely simple reaction picture (quasi-free knockout of a single nucleon or electroproduction of an isobar) and a simple nuclear model (Fermi gas) have provided both a good fit to experimental data and a dynamical determination of the nuclear Fermi momentum (k/sub F/). However, there exists an anomalous region where this picture fails. Two body correlations have not seemed to help give any better agreement. We have investigated the following questions: Do exchange current processes contribute importantly in this region. Do they help produce agreement with experiment. Also, how do they effect our previous picture of quasifree knockout. We calculate the effects of exchange currents in this region using the standard Feynman graph rules. We have included all important long range exchange currents: pair, pionic, and isobar exchange currents. We found it necessary to make non-relativistic reductions of these currents in order to facilitate calculations. The resulting multidimensional integrals were done using Monte Carlo techniques. All exchange currents which were investigated were found to be appreciable in the anomalous region, and also important in the quasi-free peak region. Inclusion of these amplitudes would supply all of the missing cross section in the anomalous region: however, it would destroy the agreement between theory and experiment in the region of the quasi-free nucleon peak, and thereby cast suspicion on the aforementioned dynamical determination of k/sub F/

Application of a finite element method to leak before break (LBB) of a heat exchanger

International Nuclear Information System (INIS)

Lee, Choon-Yeol; Kwon, Jae-Do; Lee, Yong-Sun

2003-01-01

The leak before break (LBB) concept is difficult to apply to a structure with a thin tube that is immersed in a water environment. A heat exchanger in a nuclear power plant is such a structure. The present paper addresses an application of the LBB concept to a heat exchanger in a nuclear power plant. The minimum leaked coolant amount containing the radioactive material which can activate the radiation detector device installed near the heat exchanger is assumed. The postulated initial flaw size that cannot grow to the critical flaw size within the time period to activate the radiation detector is justified. In this case, the radiation detector can activate the warning signal caused by coolant leakage from initially postulated flaws of the heat exchanger. The nuclear plant can safely shutdown when this occurs. Since the postulated initial flaw size can not grow to the critical flaw size, the structural integrity of the heat exchanger is not impeded. Particularly the informational scenario presented in this paper discusses an actual nuclear plant. (author)

Selective cation-exchange separation of cesium(I) on chromium ferricyanide gel

International Nuclear Information System (INIS)

Jain, A.K.; Agrawal, S.; Singh, R.P.

1980-01-01

The removal of 137 Cs from liquid streams of nuclear power plants and from processed radioactive waste of nuclear fission has received increasing attention from ion-exchange chemists. A desirable exchanger (adsorbent) for 137 Cs removal is one which can adsorb it significantly and selectively in the presence of appreciable amounts (approx. 2molL -1 ) of Na + , NH 4 + , and H + . This paper deals with the exchange properties of the inorganic exchanger, chromium ferricyanide gel (CFiC). The stability of the gel in both acid and salt solutions and its high specificity for cesium are responsible for its good scavanger properties in removing long lived 137 Cs from radioactive waste. The chromium ferricyanide exchanger is highly selective for monovalent cations, the order being Ag + >Tl + >Cs + >Rb + >K + >Na + . It does not adsorb any bivalent, trivalent, and tetravalent ions even when present in trace amounts. (2 figures, 3 tables)

Prospects for inherently safe reactors

International Nuclear Information System (INIS)

Barkenbus, J.N.

1988-01-01

Public fears over nuclear safety have led some within the nuclear community to investigate the possibility of producing inherently safe nuclear reactors; that is, reactors that are transparently incapable of producing a core melt. While several promising designs of such reactors have been produced, support for large-scale research and development efforts has not been forthcoming. The prospects for commercialization of inherently safe reactors, therefore, are problematic; possible events such as further nuclear reactor accidents and superpower summits, could alter the present situation significantly. (author)

Nuclear Spin Relaxation

Indian Academy of Sciences (India)

IAS Admin

ments have shown that in some cases the nuclear spin systems may be held in special configurations called .... these methods have been commercialized, and used for clinical trials, in which hyperpolarized NMR is used to .... symmetric under exchange, meaning that exchanging the two nuclei leaves the state unchanged.

Heat exchangers in heavy water reactor systems

International Nuclear Information System (INIS)

Mehta, S.K.

1988-01-01

Important features of some major heat exchange components of pressurized heavy water reactors and DHRUVA research reactor are presented. Design considerations and nuclear service classifications are discussed

Increasing of prediction reliability of calcium carbonate scale formation in heat exchanger of secondary coolant circuits of thermal and nuclear power plants

International Nuclear Information System (INIS)

Tret'yakov, O.V.; Kritskij, V.G.; Styazhkin, P.S.

1991-01-01

Calcium carbonate scale formation in the secondary circuit heat exchanger of thermal and nuclear power plants is investigated. A model of calcium-carbonate scale formation providing quite reliable prediction of process running and the possibility of its control affecting the parameters of hydrochemical regime (HCR) is developed. The results can be used when designing the automatic-control system of HCR

Exchange of Notes constituting an Agreement concerning the application of the Agreement between Australia and the United States of America concerning peaceful uses of Nuclear Energy

International Nuclear Information System (INIS)

1985-01-01

This Agreement was concluded by an Exchange of notes constituting an Agreement between the Governments of Australia and the United States and concerns the application of different Articles in the Agreement of 5th July 1979 concerning peaceful uses of nuclear energy which entered into force on 16th January 1981. It details each Party's responsibilities regarding safeguards, physical protection and retransfers of nuclear material. It entered into force on the day of its signature and will remain in force for as long as the Agreement between both countries concerning peaceful uses of nuclear energy. (NEA) [fr

Lattice QCD simulation of meson exchange forces

International Nuclear Information System (INIS)

Richards, D.G.; Sinclair, D.K.; Sivers, D.

1990-01-01

We present the formalism for investigating the bar Qq bar Qq system in lattice QCD. This system serves as a model for describing exchange forces between heavy, static hadrons. We use this formalism to calculate the exchange potential from gauge configurations which incorporate the effects of dynamical quarks. Our data can be interpreted as giving preliminary results on the range of the nuclear force

Quantum-CEP processing spent ion exchange resins from nuclear power stations

International Nuclear Information System (INIS)

Kaczmarsky, Myron

1997-01-01

Quantum-CEP (Q-CEP) is an innovative and proprietary technology developed by Molten Metal Technology, Inc, which can process radioactive and mixed waste streams to decontaminate and recover resources of commercial value while achieving significant volume reduction and radionuclide stabilization. A Q-CEP facility, located in Oak Ridge, Tennessee, processes low-level radioactive spent ion exchange resins (IER) from U.S commercial nuclear power plants. The first campaign processing low level radioactive spent IER was successfully completed in December 1996. Other milestones, since December, include operating parallel Trains A and B simultaneously and processing 25,000 lb. dry resin (50,000 lb. wet resin) or six equivalent High Integrity Containers (HICs) in one batch campaign, in March; and processing 50,000 lb. dry resin or 12 equivalent HICs in one batch campaign in May. This paper presents results from the March campaign (97-008) in which 25,000 lb. of dry spent IER from five nuclear power stations were processed. This campaign has been selected since it is representative of campaigns completed during the first five months of operation. Key highlights for this campaign include processing six HICs in batch campaign while achieving a volume reduction of 24: 1. Key performance targets for the facility are to process an average of six HICs per campaign batch and achieve a volume reduction of 30: 1. The average batch size and other performance parameters have steadily improved during the initial operating period with radioactive resin. The progress was dramatically demonstrated by the May campaign during which 12 HICs were processed - achieving a volume reduction estimated to exceed 50: 1. The campaigns in March and May demonstrate that the facility's design and technology are capable of achieving and even exceeding the facility's key target performance parameters

Nuclear knowledge and information management in Croatia

International Nuclear Information System (INIS)

Pleslic, S.; Novosel, N.

2004-01-01

Since the IAEA was authorized for exchange of technical and scientific information on peaceful uses of atomic energy, it established INIS in 1970 as an international bibliographic database in nuclear field and in nuclear related areas. All Member States, which are at different levels of technological development, could derive benefits from INIS output products and get the support from the IAEA in systematic knowledge preservation and information exchange. Intention is the transferring of practical experience to the younger generation and the archiving of important information. Croatia is successfully involved in activities in knowledge and information management from 1994 when joined INIS. Accumulation of knowledge including technical information in databases and documents, and knowledge of scientists, engineers, researchers and technicians is base for the use of nuclear technology. Nuclear knowledge and information exchange are important for process of decision-making. Thanks to development and application of new information technologies within INIS information management framework, Members improve the collection, production and dissemination of nuclear knowledge and information. (author)

Auxiliary heat exchanger for a gas-cooled nuclear reactor

International Nuclear Information System (INIS)

Ecker, H.; Gasch, K.; Lischer, R.; Spilker, H.

1978-01-01

The proposal concerns the design configuration of the individual components of a heat exchanger with circular cross-section, being placed within a lined pod of the concrete shell of the pressure vessel. The heat exchanger has got a vertical cooler installed below the circulator. The components are arranged in such manner that the access to the pipe lines for in-service inspections is assured. Uniform velocity distribution of the gas streaming into the cooler from below is to be achieved. (GL) 891 GL/GL 892 MKO [de

New anion-exchange resins for improved separations of nuclear materials

International Nuclear Information System (INIS)

Barr, M.E.; Bartsch, R.A.

1998-01-01

'The overall objective of this research is to develop a predictive capability which allows the facile design and implementation of multi-functionalized anion-exchange materials which selectively sorb metal complexes of interest from targeted process, waste, and environmental streams. The basic scientific issues addressed are actinide complex speciation along with modeling of the metal complex/functional-site interactions in order to determine optimal binding-site characteristics. The new ion-exchange resins interface the rapidly developing field of ion-specific chelating ligands with robust, commercial ion-exchange technology. Various Focus Areas and Crosscutting Programs have described needs that would be favorably impacted by the new materials: Efficient Separations and Processing; Plutonium; Plumes; Mixed Waste; High-Level Tank Waste. Sites within the DOE complex which would benefit from the improved anion-exchange technology include Hanford, INEL, Los Alamos, Oak Ridge, and Savannah River. As of April 1998, this report summarizes work after 1.6 years of a 3-year project. The authors technical approach combines empirical testing with theoretical modeling (applied in an iterative mode) in order to determine optimal binding-site characteristics. They determine actinide-complex speciation in specific media, then develop models for the metal complex/functional-site interactions Synthesis and evaluation of multi-functionalized extractants and ion-exchange materials that implement key features of the optimized binding site provide feedback to the modeling and design activities. Resin materials which actively facilitate the uptake of actinide complexes from solution should display both improved selectivity and kinetic properties. The implementation of the bifunctionality concept involves N-derivatization of pyridinium units from a base poly(4-vinylpyridine) resin with a second cationic site such that the two anion-exchange sites are linked by spacer arms of varying

Theoretical studies in nuclear physics

International Nuclear Information System (INIS)

Landau, R.H.; Madsen, V.A.

1991-01-01

This report discusses research in nuclear theory in the following areas: Isospin effects and charge exchange; inelastic and charge exchange scattering; momentum space proton scattering; pion scattering from nuclei; and antiproton studies. 14 refs

High-capacity, selective solid sequestrants for innovative chemical separation: Inorganic ion exchange approach

International Nuclear Information System (INIS)

Bray, L.

1995-01-01

The approach of this task is to develop high-capacity, selective solid inorganic ion exchangers for the recovery of cesium and strontium from nuclear alkaline and acid wastes. To achieve this goal, Pacific Northwest Laboratories (PNL) is collaborating with industry and university participants to develop high capacity, selective, solid ion exchangers for the removal of specific contaminants from nuclear waste streams

Method of pyrolysis for spent ion-exchange resins

International Nuclear Information System (INIS)

Aoyama, Yoshiyuki; Matsuda, Masami; Kawamura, Fumio; Yusa, Hideo.

1985-01-01

Purpose: To prevent the generation of noxious sulfur oxide and ammonia on the pyrolysis for spent ion-exchange resins discharged from nuclear power plants. Method: In the case where the pyrolysis is made for the cationic exchange resins having sulfonic acids as the ion-exchange group, alkali metals or alkaline earth metals capable of reacting with sulfonic acid groups to form solid sulfates are previously deposited by way of ion-exchange reactions prior to the pyrolysis. In another case of the anionic exchange resins having quarternary ammonium groups as the ion-exchange groups, halogenic elements capable of reacting with the ammonium groups to form solid ammonium salts are deposited to the ion-exchange resins through ion-exchange reactions prior to the pyrolysis. As a result, the amount of the binders used can be reduced, and this method can be used in a relatively simple processing facility. (Horiuchi, T.)

Pionic retardation effects in two-pion-exchange three-nucleon forces

International Nuclear Information System (INIS)

Coon, S.A.; Friar, J.L.

1986-01-01

Those two-pion-exchange three-nucleon forces which arise from nuclear processes that involve only pions and nucleons are calculated. Among the processes which contribute are pion seagulls (e.g., nucleon-antinucleon pair terms) and overlapping, retarded pion exchanges. The resulting potential is shown to be a (v/c) 2 relativistic correction, and satisfies nontrivial constraints from special relativity. The relativistic ambiguities found before in treatments of relativistic corrections to the one-pion-exchange nuclear charge operator and two-body potential are also present in the three-nucleon potential. The resulting three-nucleon force differs from the original Tucson-Melbourne potential only in the presence of several new nonlocal terms, and in the specification of the choice of ambiguity parameters in the latter potential

Pionic retardation effects in two-pion-exchange three-nucleon forces

Science.gov (United States)

Coon, S. A.; Friar, J. L.

1986-09-01

Those two-pion-exchange three-nucleon forces which arise from nuclear processes that involve only pions and nucleons are calculated. Among the processes which contribute are pion seagulls (e.g., nucleon-antinucleon pair terms) and overlapping, retarded pion exchanges. The resulting potential is shown to be a (v/c)2 relativistic correction, and satisfies nontrivial constraints from special relativity. The relativistic ambiguities found before in treatments of relativistic corrections to the one-pion-exchange nuclear charge operator and two-body potential are also present in the three-nucleon potential. The resulting three-nucleon force differs from the original Tucson-Melbourne potential only in the presence of several new nonlocal terms, and in the specification of the choice of ambiguity parameters in the latter potential.

Pionic retardation effects in two-pion-exchange three-nucleon forces

Energy Technology Data Exchange (ETDEWEB)

Coon, S.A.; Friar, J.L.

1986-09-01

Those two-pion-exchange three-nucleon forces which arise from nuclear processes that involve only pions and nucleons are calculated. Among the processes which contribute are pion seagulls (e.g., nucleon-antinucleon pair terms) and overlapping, retarded pion exchanges. The resulting potential is shown to be a (v-italic/c-italic)/sup 2/ relativistic correction, and satisfies nontrivial constraints from special relativity. The relativistic ambiguities found before in treatments of relativistic corrections to the one-pion-exchange nuclear charge operator and two-body potential are also present in the three-nucleon potential. The resulting three-nucleon force differs from the original Tucson-Melbourne potential only in the presence of several new nonlocal terms, and in the specification of the choice of ambiguity parameters in the latter potential.

Nuclear parton distributions

Directory of Open Access Journals (Sweden)

Kulagin S. A.

2017-01-01

Full Text Available We review a microscopic model of the nuclear parton distribution functions, which accounts for a number of nuclear effects including Fermi motion and nuclear binding, nuclear meson-exchange currents, off-shell corrections to bound nucleon distributions and nuclear shadowing. We also discuss applications of this model to a number of processes including lepton-nucleus deep inelastic scattering, proton-nucleus Drell-Yan lepton pair production at Fermilab, as well as W± and Z0 boson production in proton-lead collisions at the LHC.

J~S 3 :F ~: () - - -I =S

African Journals Online (AJOL)

played a crucial role. France,. Italy, Portugal,. Greece, Germany and many others have been ruled by army officers. From 1914 to 1923 Spain underwent 43 successful and unsuccessful military coups. Eventhe two superpowers, both committed to strict control of their military because of fear of nuclear war, have suffered from ...

[Intermediate energy nuclear physics

International Nuclear Information System (INIS)

1989-01-01

This report summarizes work in experimental Intermediate Energy Nuclear Physics carried out between October 1, 1988 and October 1, 1989 at the Nuclear Physics Laboratory of the University of Colorado, Boulder, under grant DE-FG02-86ER-40269 with the United States Department of Energy. The experimental program is very broadly based, including pion-nucleon studies at TRIUMF, inelastic pion scattering and charge exchange reactions at LAMPF, and nucleon charge exchange at LAMPF/WNR. In addition, a number of other topics related to accelerator physics are described in this report

Crisis phenomena and sources of instability

International Nuclear Information System (INIS)

Ball, D.; Bethe, H.A.; Blair, B.G.; Bracken, P.; Carter, A.B.; Dickinson, H.; Garwin, R.L.; Holloway, D.; Kendall, H.W.

1988-01-01

What are the most likely paths that might carry a crisis to nuclear war between the superpowers? Are those paths marked by critical junctures or patterns that recur and are amenable to analysis? These questions form the crux of this study, but history provides a meager data base for answering them. Only once, during the Cuban Missile Crisis, did nuclear war appear to be a conceivable consequence of steps already taken or under serious consideration. To prepare a springboard for that extrapolation, we must first examine the settings in which leaders have coped with crises, and identify features that are likely to recur in future confrontations. These features include the environment that in the past has differentiated crisis from peace and war; the dominant factors that have been (or should have been) assessed either at the outbreak of crisis or as events unfolded; the human dimension of crisis; domestic and alliance politics; intelligence; and the trade-offs between diplomacy and military measures that have chronically perplexed leaders during a crisis. The authors of this paper consider confrontations of an intensity with which the world has no experience: direct conflict, either conventional or nuclear, between the superpowers

Probing nuclear correlations with pion-nucleus double charge exchange

International Nuclear Information System (INIS)

Ginocchio, J.N.

1988-01-01

In this paper we have calculated the lowest order pion double charge reaction mechanism using shell model wavefunctions of medium weight nuclei. We have the sequential reaction mechanism in which the pion undergoes two single-charge exchange scatterings on the valence neutrons. The distortion of the incoming, intermediate, and outgoing pion are included. The closure approximation is made for the intermediate states with an average excitation energy used in the pion propagator. The double-charge exchange is assumed to take place on the valence nucleons which are assumed to be in one spherical shell model orbital. 34 refs., 5 figs., 3 tabs

On-Line Monitoring and Diagnostics of the Integrity of Nuclear Plant Steam Generators and Heat Exchangers

International Nuclear Information System (INIS)

Upadhyaya, Belle R.; Wesley Hines, J.

2004-01-01

The overall purpose of this Nuclear Engineering Education Research (NEER) project was to integrate new, innovative, and existing technologies to develop a fault diagnostics and characterization system for nuclear plant steam generators (SG) and heat exchangers (HX). Issues related to system level degradation of SG and HX tubing, including tube fouling, performance under reduced heat transfer area, and the damage caused by stress corrosion cracking, are the important factors that influence overall plant operation, maintenance, and economic viability of nuclear power systems. The research at The University of Tennessee focused on the development of techniques for monitoring process and structural integrity of steam generators and heat exchangers. The objectives of the project were accomplished by the completion of the following tasks. All the objectives were accomplished during the project period. This report summarizes the research and development activities, results, and accomplishments during June 2001-September 2004. (1) Development and testing of a high-fidelity nodal model of a U-tube steam generator (UTSG) to simulate the effects of fouling and to generate a database representing normal and degraded process conditions. Application of the group method of data handling (GMDH) method for process variable prediction. (2) Development of a laboratory test module to simulate particulate fouling of HX tubes and its effect on overall thermal resistance. Application of the GMDH technique to predict HX fluid temperatures, and to compare with the calculated thermal resistance. (3) Development of a hybrid modeling technique for process diagnosis and its evaluation using laboratory heat exchanger test data. (4) Development and testing of a sensor suite using piezo-electric devices for monitoring structural integrity of both flat plates (beams) and tubing. Experiments were performed in air, and in water with and without bubbly flow. (5) Development of advanced signal

On-Line Monitoring and Diagnostics of the Integrity of Nuclear Plant Steam Generators and Heat Exchangers.

Energy Technology Data Exchange (ETDEWEB)

Belle R. Upadhyaya; J. Wesley Hines

2004-09-27

The overall purpose of this Nuclear Engineering Education Research (NEER) project was to integrate new, innovative, and existing technologies to develop a fault diagnostics and characterization system for nuclear plant steam generators (SG) and heat exchangers (HX). Issues related to system level degradation of SG and HX tubing, including tube fouling, performance under reduced heat transfer area, and the damage caused by stress corrosion cracking, are the important factors that influence overall plant operation, maintenance, and economic viability of nuclear power systems. The research at The University of Tennessee focused on the development of techniques for monitoring process and structural integrity of steam generators and heat exchangers. The objectives of the project were accomplished by the completion of the following tasks. All the objectives were accomplished during the project period. This report summarizes the research and development activities, results, and accomplishments during June 2001-September 2004. (1) Development and testing of a high-fidelity nodal model of a U-tube steam generator (UTSG) to simulate the effects of fouling and to generate a database representing normal and degraded process conditions. Application of the group method of data handling (GMDH) method for process variable prediction. (2) Development of a laboratory test module to simulate particulate fouling of HX tubes and its effect on overall thermal resistance. Application of the GMDH technique to predict HX fluid temperatures, and to compare with the calculated thermal resistance. (3) Development of a hybrid modeling technique for process diagnosis and its evaluation using laboratory heat exchanger test data. (4) Development and testing of a sensor suite using piezo-electric devices for monitoring structural integrity of both flat plates (beams) and tubing. Experiments were performed in air, and in water with and without bubbly flow. (5) Development of advanced signal

Decomposing method for ion exchange resin

International Nuclear Information System (INIS)

Sako, Takeshi; Sato, Shinshi; Akai, Yoshie; Moniwa, Shinobu; Yamada, Kazuo

1998-01-01

The present invention concerns a method of decomposing ion exchange resins generated in a nuclear power plant to carbon dioxide reliably in a short period of time. (1) The ion exchange resins are mixed with water, and then they are kept for a predetermined period of time in the presence of an inert gas at high temperature and high pressure exceeding the critical point of water to decompose the ion exchange resins. (2) The ion exchange resins is mixed with water, an oxidant is added and they are kept for a predetermined time in the presence of an inert gas at a high temperature and a high pressure exceeding a critical point of water of an inert gas at a high temperature to decompose the ion exchange resins. (3) An alkali or acid is added to ion exchange resins and water to control the hydrogen ion concentration in the solution and the ion exchange resins are decomposed in above-mentioned (1) or (2). Sodium hydroxide is used as the alkali and hydrochloric acid is used as the acid. In addition, oxygen, hydrogen peroxide or ozone is used as an oxidant. (I.S.)

Nuclear magnetic relaxation induced by exchange-mediated orientational randomization: longitudinal relaxation dispersion for a dipole-coupled spin-1/2 pair.

Science.gov (United States)

Chang, Zhiwei; Halle, Bertil

2013-10-14

In complex biological or colloidal samples, magnetic relaxation dispersion (MRD) experiments using the field-cycling technique can characterize molecular motions on time scales ranging from nanoseconds to microseconds, provided that a rigorous theory of nuclear spin relaxation is available. In gels, cross-linked proteins, and biological tissues, where an immobilized macromolecular component coexists with a mobile solvent phase, nuclear spins residing in solvent (or cosolvent) species relax predominantly via exchange-mediated orientational randomization (EMOR) of anisotropic nuclear (electric quadrupole or magnetic dipole) couplings. The physical or chemical exchange processes that dominate the MRD typically occur on a time scale of microseconds or longer, where the conventional perturbation theory of spin relaxation breaks down. There is thus a need for a more general relaxation theory. Such a theory, based on the stochastic Liouville equation (SLE) for the EMOR mechanism, is available for a single quadrupolar spin I = 1. Here, we present the corresponding theory for a dipole-coupled spin-1/2 pair. To our knowledge, this is the first treatment of dipolar MRD outside the motional-narrowing regime. Based on an analytical solution of the spatial part of the SLE, we show how the integral longitudinal relaxation rate can be computed efficiently. Both like and unlike spins, with selective or non-selective excitation, are treated. For the experimentally important dilute regime, where only a small fraction of the spin pairs are immobilized, we obtain simple analytical expressions for the auto-relaxation and cross-relaxation rates which generalize the well-known Solomon equations. These generalized results will be useful in biophysical studies, e.g., of intermittent protein dynamics. In addition, they represent a first step towards a rigorous theory of water (1)H relaxation in biological tissues, which is a prerequisite for unravelling the molecular basis of soft

Basic thermo-fluid dynamic problems in high temperature heat exchangers

International Nuclear Information System (INIS)

McEligot, D.M.

1986-01-01

The authors consider high temperature heat exchangers to be ones where the heat transfer coefficients cannot be predicted confidently by classical analyses for pure forced convection with constant fluid properties. Alternatively, one could consider heat exchangers operating above some arbitrary temperature, say 1000F or 600C perhaps, to be at high temperature conditions. In that case, most common working fluids will be superheated vapors or gases. While some liquid metal heat exchangers are designed to operate in this range, the heat transfer coefficients of liquid metals are usually sufficiently high that the dominant thermal resistance would be due to the second fluid. This paper concentrates on convective heat transfer with gases. Typical applications include modular gas cooled nuclear reactors, proposed nuclear propulsion systems and space power plants, and superheaters in Rankine steam cycles

New concept for nuclear force: implications for nuclear structure and hadronic processes

International Nuclear Information System (INIS)

Kukulin, V.I.

2005-01-01

Full text: A new concept for nuclear force is discussed. The concept is based on idea about production of the intermediate six-quark bag (dibaryon) dressed with meson fields main of which are π-, σ-, p-, and ω-fields. The whole approach has been strongly motivated by our previous detailed analysis of various inner contradictions and inconsistencies in the conventional meson-exchange (i.e. Yukawa like) mechanism of nuclear force. The new force model predicts inevitable strong attractive 3N-force of scalar nature originated from σ-exchange between the dressed dibaryon and third nucleon. This new 3N-force has been demonstrated earlier to result in, at least, a half the total binding energy in lightest nuclei and contribute strongly to all nuclear properties like r. m. s. charge radius, nucleon momentum distribution, new electromagnetic currents and leads, very likely, to new understanding of saturation properties in nuclear matter. In the talk many other implications of the suggested new force model in hadronic and nuclear physics will be discussed

Fragmentary model of exchange interactions

CERN Document Server

Kotov, V M

2000-01-01

This article makes attempt to refusal from using neutrino for explanation continuous distribution of beta particle energy by conversion to characteristic exchange interaction particles in nucleolus. It is taking formulation for nuclear position with many different fragments. It is computing half-value period of spontaneous fission of heavy nucleolus. (author)

Immobilization of ion exchange radioactive resins of the TRIGA Mark III nuclear reactor; Inmovilizacion de resinas de intercambio ionico radiactivas del reactor nuclear Triga Mark III

Energy Technology Data Exchange (ETDEWEB)

Garcia M, H.; Emeterio H, M.; Canizal S, C. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, C.P. 11801 Mexico D.F. (Mexico)

2000-07-01

This work has the objective to develop the process and to define the agglutinating material which allows the immobilization of the ion exchange radioactive resins coming from the TRIGA Mark III nuclear reactor contaminated with Ba-133, Co-60, Cs-137, Eu-152, and Mn-54 through the behavior analysis of different immobilization agents such as: bitumens, cement and polyester resin. According to the International Standardization the archetype samples were observed with the following tests: determination of free liquid, leaching, charge resistance, biodegradation, irradiation, thermal cycle, burned resistance. Generally all the tests were satisfactorily achieved, for each agent. Therefore, the polyester resin could be considered as the main immobilizing. (Author)

New portable monitor enhances the ability to evaluate heat exchanger performance

International Nuclear Information System (INIS)

O'Toole, W.; Lacy, J.R.; Karlovich, D.N.

1992-01-01

Corrosion and fouling problems in nuclear power plant service water systems have led to industry-wide concern. These problems can affect the ability of these important heat exchangers to remove design heat loads. In addition, a limited amount of permanently installed on-line instrumentation is available to monitor key heat transfer parameters. A new, computerized monitoring system has been developed that acquires and manipulates process data. This enables power plant personnel to evaluate the on-line performance of important cooling system heat exchangers. The equipment provides the capability to continuously monitor, graph, and record cooling and process heat transfer parameters. The computer hardware is in a portable cabinet on wheels, which can be easily rolled from exchanger to exchanger for monitoring. This new monitoring system is being used at Consolidated Edison Company of New York Inc.'s Indian Point 2 Nuclear Station. They are currently expanding their performance testing on service water system heat exchangers and other auxiliary components to include those units that have limited on-line instrumentation. The ability to use clamp on flow and temperature sensing devices is necessary for trending exchanger performance. With on-line testing capabilities it is possible to: evaluate the cleanliness of plant heat transfer surfaces; make judgments about biofouling or antiscalant programs; and determine when equipment needs to be shut down for inspection or cleaning This paper describes this state-of-the-art equipment in detail and its application at the Indian Point 2 Nuclear Station. 9 refs., 8 figs., 1 tab

Biodegradation of ion-exchange media

International Nuclear Information System (INIS)

Bowerman, B.S.; Clinton, J.H.; Cowdery, S.R.

1988-08-01

Ion-exchange media, both bead resins and powdered filter media, are used in nuclear power plants to remove radioactivity from process water prior to reuse or environmental discharge. Since the ion- exchange media are made from synthetic hydrocarbon-based polymers, they may be susceptible to damage from biological activity. The purpose of this study was to investigate some of the more basic aspects of biodegradation of ion-exchange media, specifically to evaluate the ability of microorganisms to utilize the ion-exchange media or materials sorbed on them as a food source. The ASTM-G22 test, alone and combined with the Bartha Pramer respirometric method, failed to indicate the biodegradability of the ion-exchange media. The limitation of these methods was that they used a single test organism. In later phases of this study, a mixed microbial culture was grown from resin waste samples obtained from the BNL High Flux Beam Reactor. These microorganisms were used to evaluate the susceptibility of different types of ion-exchange media to biological attack. Qualitative assessments of biodegradability were based on visual observations of culture growths. Greater susceptibility was associated with increased turbidity in solution indicative of bacterial growth, and more luxuriant fungal mycelial growth in solution or directly on the ion-exchange resin beads. 21 refs., 9 figs., 18 tabs

Recent initiative in information exchange throughout the international nuclear community

International Nuclear Information System (INIS)

Simard, R.L.

1983-01-01

Two key systems essential to the gathering and dissemination of operating experience, the Nuclear Plant Reliability Data System (NPRDS) and NUCLEAR NOTEPAD are described. The NPRDS is a collection of detailed engineering data on systems and components important to nuclear plant safety and productivity. NUCLEAR NOTEPAD is an international telecommunications network which provides a mechanism for the rapid, widespread dissemination of information pertinent to the design, licensing, safe and reliable operation of nuclear plants. Both systems have been managed by the Institute of Nuclear Power Operations since 1982 and are used extensively by 84 organizations in 14 countries. (U.K.)

Nuclear code abstracts (1975 edition)

International Nuclear Information System (INIS)

Akanuma, Makoto; Hirakawa, Takashi

1976-02-01

Nuclear Code Abstracts is compiled in the Nuclear Code Committee to exchange information of the nuclear code developments among members of the committee. Enlarging the collection, the present one includes nuclear code abstracts obtained in 1975 through liaison officers of the organizations in Japan participating in the Nuclear Energy Agency's Computer Program Library at Ispra, Italy. The classification of nuclear codes and the format of code abstracts are the same as those in the library. (auth.)

Characterization and disposal of ion exchange resins used in nuclear installations; Caracterizacion y disposicion de resinas de intercambio ionico utilizadas en instalaciones nucleares

Energy Technology Data Exchange (ETDEWEB)

Flores E, R.M.; Ortiz O, H.B.; Olguin G, M.T.; Emeterio H, M.; Garcia M, H. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2006-07-01

To dispose of an appropriate way the used ion exchange resins so much in the pool water purification systems of the TRIGA Mark III reactor like in the JS6500 gamma irradiator, of the National Institute of Nuclear Research, were carried out a series of analytic nuclear techniques and complementary conventional to those recommended by the ASTM, with the object of to control and to manage 14 lots of worn out resins appropriately. For its were identified the radioactive isotopes, the resins type, the grade of chemical pollution and the physicochemical degradation of the same ones. The lots of resins that didn't contain radioactive isotopes its were regenerated in an usual way, as long as those that if they controlled them they selected options for its final disposition. The first selected option was the extraction method of ion radioactive isotopes, concentrating the elution product by evaporation. As second option it was carried out the resins stabilization damaged by micro-encapsulation by forged to ambient temperature, using an organic polymer. Previous to the immobilization the resins were pretreated by vacuum drying, pulverization and thermal drying, however before carrying out this last, it was carried out a thermal gravimetric analysis to determine the drying conditions of the resins avoiding its chemical decomposition. (Author)

Nuclear data newsletter. No. 3

Energy Technology Data Exchange (ETDEWEB)

NONE

1981-03-01

This issue describes the ENDF/B-5 nuclear data library format which can be considered as the international format for the exchange of evaluated neutron reaction data. It lists the new nuclear data libraries recently received by the Nuclear Data Section of the IAEA, as well as a selection of new relevant documents.

Literature study of volatile radioiodine release from ion-exchange resins during transportation

International Nuclear Information System (INIS)

Wren, J.C.

1991-02-01

A transport package is currently being developed by Ontario Hydro to carry used filters and ion-exchange columns from the Pickering and Darlington Nuclear Generating Stations to the Bruce Nuclear Generating Station for disposal. The main reason that the transport package must be licensed is the possibility that volatile radionuclides being transported in the package might be released during transport accidents. Of particular concern is the iodine that might become volatile due to the degradation of the ion exchange resin. This report reviews the literature on the thermal and radiolytic degradation of ion exchange resins and provides calculations to estimate the fraction of volatile iodine as a function of time under postulated accident conditions

Plate heat exchangers in the power plant industry

International Nuclear Information System (INIS)

Wersel, M.; Ridell, B.

1984-01-01

An increase in heat transfer and stability, small investment, high flexibility, easy maintenance and corrosion resistance are obtained by the design and construction of plate heat exchangers and by the introduction of the herringbone pattern. The plate heat exchanger can be used in nearly 90% of all secondary circuits in powerstations. Examples of its installation are the WYLFA, GENTILLY, RINGHALS and TVO Finland nuclear power-stations. (DG) [de

Safety technology for air-cooled heat exchangers

International Nuclear Information System (INIS)

Kawai, Masafumi; Miyamoto, Hitoshi

2011-01-01

The air-cooled heat exchanger is a device that enables a large amount of heat exchange (cooling) by utilizing the atmosphere as a stable and infinite heat sink. It is widely used in general industrial plants, and nowadays it is also utilized in nuclear facilities. This type of exchanger is advantageous in that it can be constructed in any location without having to be near the sea or rivers. It can be operated safely if a natural disaster, such as a tsunami or flood, occurs, thus contributing to the safety of the mother facility. IHI's air-cooled heat exchangers are designed to ensure safe operation and withstand a large earthquake or severe atmospheric conditions. This report describes the technologies used to establish these safety features and their performance. (author)

Reaction mechanisms in coherent nuclear photoproduction

International Nuclear Information System (INIS)

Lazard, C.

Nuclear coherent pion photoproduction is studied. Pion rescattering and propagation effects inside nucleus and mesic exchange current effects are discussed. Influence of nuclear wave functions and Fermi motion is presented [fr

Exchange and fellowship programme

Energy Technology Data Exchange (ETDEWEB)

NONE

1959-04-15

By February 1959, the IAEA had received and considered nearly 300 nominations from 31 countries for nuclear science fellowships. More than 200 of the candidates - from 29 countries - had been selected for placement in centres of training in 21 countries. The programme covers three types of training: 1. General techniques training: to develop skills in the use of some fundamental techniques in the field of nuclear energy; 2. Specialist training: to prepare specialists in the theoretical and experimental aspects of the science and technology of nuclear energy; 3. Research training: to provide advanced training, including active participation in research work; this is for persons potentially qualified to develop and carry out research programmes in the basic sciences and engineering. The duration of training varies from some weeks to five or six years. The long-duration training is given at universities or educational establishments of university level, and is of special interest to Member States lacking personnel with the requisite university education. Under its 1959 exchange and fellowship programme, the Agency will be in a position to award over 400 fellowships. Some of these will be paid out of the Agency's operating fund, while 130 fellowships have been offered directly to IAEA by Member States for training at their universities or institutes. There are two new features in the Agency's 1959 programme. One provides for fellowships for scientific research work, the other is the exchange of specialists

Nuclear waste in Seibersdorf

International Nuclear Information System (INIS)

Anon.

1988-01-01

Forschungszentrum Seibersdorf (short: Seibersdorf) is the company operating the research reactor ASTRA. A controversy arose, initied by the Greens and some newspapers on the fact that the waste conditioning plant in Seibersdorf treated not only Austrian waste (from hospitals etc.) but also a large quantity of ion exchange resins from the Caorso nuclear power station, against payment. The author argues that it is untenable that an Austrian institution (peaceful use of nuclear energy in Austria being abandoned by a referendum) should support nuclear power abroad. There is also a short survey on nuclear waste conditioning and an account of an exchange of letters, between the Seibersdorf and the Ecology Institute on the claim of being an 'independent measuring institution' of food, soil, etc. samples. The author argues that the Ecology Institute is the sole independent institution in Austria because it is part of the ecology- and antinuclear movement, whereas Seibersdorf is dependent on the state. (qui)

Proceedings of VII International Symposium on Nuclear and Related Techniques. XIII Workshop on Nuclear Physics. WONP-NURT 2011

International Nuclear Information System (INIS)

2011-02-01

This year the XIII Workshop on Nuclear Physics (WONP) and the VII Symposium on Nuclear and Related Techniques (NURT) are organized jointly, by Instituto Superior de Tecnologias y Ciencias Aplicadas and Centro de Aplicaciones Tecnologicas y Desarrollo Nuclear. Both events gather scientists from several countries with top research work on nuclear physics and its applications. WONP has been carried out since 1994 promoting an ever-exchanging exchange between professionals of various nuclear and applied physics fields, those related to environmental and health care. NURT is one of the key Cuban scientific meetings since 1997 dealing with the peaceful applications of nuclear techniques in several domains of the society. WONP and NURT provide an unique opportunity for the national and international scientific community to meet outstanding researchers and discuss current trends in several areas of theoretical, experimental and applied nuclear physics and related topics. The papers submitted to this event are presented in this CD-ROM

Proceedings of VI International Symposium on Nuclear and Related Techniques. XII Workshop on Nuclear Physics. WONP-NURT 2009

International Nuclear Information System (INIS)

2009-02-01

This year the XII Workshop on Nuclear Physics (WONP) and the VI Symposium on Nuclear and Related Techniques (NURT) are organized jointly, by Instituto Superior de Tecnologias y Ciencias Aplicadas and Centro de Aplicaciones Tecnologicas y Desarrollo Nuclear. Both events gather scientists from several countries with top research work on nuclear physics and its applications. WONP has been carried out since 1994 promoting an ever-exchanging exchange between professionals of various nuclear and applied physics fields, those related to environmental and health care. NURT is one of the key Cuban scientific meetings since 1997 dealing with the peaceful applications of nuclear techniques in several domains of the society. WONP and NURT provide an unique opportunity for the national and international scientific community to meet outstanding researchers and discuss current trends in several areas of theoretical, experimental and applied nuclear physics and related topics. The papers submitted to this event are presented in this CD-ROM

Protocol between the Nuclear Protection and Safety Bureau representing the Nuclear Authorities of Portugal and the Nuclear Energy Commission of Spain on Co-operation in Nuclear Safety

International Nuclear Information System (INIS)

1980-01-01

This Protocol was signed further to the Agreement between Portugal and Spain on 14 January 1971 on co-operation in the peaceful use of nuclear energy. It provides for exchange of information on the general aspects of nuclear safety and radiation protection; study of the basic characteristics of siting, construction, operation and decommissioning of nuclear installations, and experience acquired in these areas; the problematics of planning against nuclear incidents and their environmental impact; legislation, regulations and technical standards concerning nuclear installations. The Protocol entered into force for a period of five years on the day of its signature. (NEA) [fr

Fuel exchanger for nuclear ships

International Nuclear Information System (INIS)

Suda, Koji; Kanbara, Takahisa; Watanabe, Masaharu.

1984-01-01

Purpose: To prevent enviromental contamination landing radioactive materials from the inside of a ship. Constitution: A provisional cabin having a shape covering a reactor hatch and a hatch cover is disposed on the upper deck of a ship body. A ceiling shutter is disposed to the cabin. A protection cylinder having a shutter and a filter fan is attached on the cabin. Materials to be discharged out of the ship are transported to a fuel exchange tower on land by using a crane while being contained in the protection cylinder with the shutter being closed. The protection cylinder is connected by means of a wire rope to a loop-wheel machine which disposed on the trolly of a crane. While the bellows through which the suspending wire for the discharged products passes is perforated, since the inside of the cylinder is depressurized by a filter fan, there is no air leakage through the perforation to the outside. (Ikeda, J.)

Fuel exchanger for nuclear ships

Energy Technology Data Exchange (ETDEWEB)

Suda, Koji; Kanbara, Takahisa; Watanabe, Masaharu

1984-11-29

To prevent enviromental contamination by radioactive materials from the inside of a ship a provisional cabin having a shape covering a reactor hatch and a hatch cover is disposed on the upper deck of a ship body. A ceiling shutter is disposed to the cabin. A protection cylinder having a shutter and a filter fan is attached on the cabin. Materials to be discharged out of the ship are transported to a fuel exchange tower on land by using a crane while being contained in the protection cylinder with the shutter being closed. The protection cylinder is connected by means of a wire rope to a loop-wheel machine which is disposed on the trolly of a crane. While the bellows through which the suspending wire for the discharged products passes is perforated, since the inside of the cylinder is depressurized by a filter fan, there is no air leakage through the perforation to the outside.

Towards a sound nuclear energy future

International Nuclear Information System (INIS)

Syrota, J.

1998-01-01

Operators of the world's nuclear plants have compiled an impressive record of improvement over the past several years. This success is due to many factors, one of which is an unprecedented level of information exchange. The Chernobyl accident in 1986, which led to the formation of World Association of Nuclear Operators (WANO), underscored the need for nuclear utilities worldwide to exchange information and cooperate in a way that transcends cultural, language and political boundaries. While the world's nuclear operators have achieved significant improvements in nuclear safety and reliability, it is an unfortunate reality that the memories of the accidents at Three Mile Island and even Chernobyl fade over time. Complacency can be the natural result of progress and success. If nuclear power is to continue to play a significant role in the world's energy mix, the positive trends of performance improvement must be sustained and enhanced - and that can best be achieved through continued mutual cooperation, and the will to avoid a natural trend toward complacency. (author)

Heat exchanger tube inspection using ultrasonic arrays

International Nuclear Information System (INIS)

Meyer, P.A.; Carodiskey, T.J.

1986-01-01

Tubing used in industrial heat exchangers is often subject to failure caused by corrosion and cracking. Technical conferences are used as a forum in the steam generator industry to ensure that the failure mechanisms are well understood and that the quality of the heat exchanger is maintained. The quality of a heat exchanger can be thought of as its ability to operate to design specifications over its intended life. This is the motivation to inspect and evaluate these devices periodically. Inspection, however, normally requires shutdown of the heat exchanger which is costly but is much more acceptable than an unscheduled shutdown due to failure of a tube. Therefore, the degree of inspection is established by balancing the cost of inspection with the risk of a tube failure. Any method of reducing the cost of inspection will permit a higher degree of inspection and, therefore, improve heat exchanger quality. This paper reviews the design and performance of an improved method of ultrasonic inspection of heat exchanger tubing with emphasis on applications in the nuclear industry

EXFOR Manual. Center-to-Center Exchange Format. Version 89-1

International Nuclear Information System (INIS)

McLane, V.

1989-09-01

EXFOR is the agreed exchange format for the transmission of nuclear reaction data between national and international nuclear data centers for the benefit of nuclear data users in all countries. EXFOR is a database with several million data records containing the world's experimental nuclear reaction data induced by neutrons, photons or charged particles. Data retrievals can be obtained from the IAEA Nuclear Data Section (NDS) or from one of the co-operating data centers whose names and addresses can be found inside the manual. Their contributions and co-operative efforts are gratefully acknowledged. (author). Refs

AESJ: communicating about nuclear issues in Japan

International Nuclear Information System (INIS)

Anon.

2016-01-01

The AESJ (Atomic Energy Society of Japan) was founded in 1959 to promote the information of the Japanese public about nuclear energy and to develop exchanges between professionals of the sector. AESJ gathers about 7000 professionals and is organized around 8 regional groups and 10 technical sessions. AESJ has been publishing 2 journals: Journal of Nuclear Science and Technology since 1964 and ATOMOΣ since 1959. AESJ also awards several prizes for promoting communication and technical achievements in nuclear activities. AESJ takes part into numerous international events like for instance supporting conferences or organizing student exchanges between research centers or universities. (A.C.)

Proceeding of the 7. Seminar on Technology and Safety of Nuclear Power Plants and Nuclear Facilities

International Nuclear Information System (INIS)

Hastowo, Hudi; Antariksawan, Anhar R.; Soetrisnanto, Arnold Y; Jujuratisbela, Uju; Aziz, Ferhat; Su'ud, Zaki; Suprawhardana, M. Salman

2002-02-01

The seventh proceedings of seminar safety and technology of nuclear power plant and nuclear facilities, held by National Nuclear Energy Agency. The Aims of seminar is to exchange and disseminate information about safety and nuclear Power Plant Technology and Nuclear Facilities consist of technology; high temperature reactor and application for national development sustain able and high technology. This seminar level all aspects technology, Power Reactor research reactor, high temperature reactor and nuclear facilities. The article is separated by index

A heat exchanger provided with plates

International Nuclear Information System (INIS)

Chaix, J.E.; Fajeau, Maurice; Chlique, Bernard.

1976-01-01

The invention relates to a heat exchanger of the plate type, in which two fluids exchange calories through parallel metal plates, delimiting spaces separated from each other in which two fluids respectively flow without direct contact between them. The invention particularly applies in the case where one of the two fluids is water under pressure or else a circulating liquid metal, specially sodium, used in the system of a pressurised water or fast neutron reactor, the second fluid being water to be vaporised in the exchanger by the calories supplied by the first fluid. The arrangement is designed to give minimum bulk, particularly enabling the exchanger to be housed in the area between the core of a nuclear reactor and a casing or outer vessel, or else in an external sealed containment, with a view to recovering with the best efficiency the heat acquired by a coolant flowing through the core [fr

Extraction of cesium and strontium from nuclear waste

Science.gov (United States)

Davis, Jr., Milton W.; Bowers, Jr., Charles B.

1988-01-01

Cesium is extracted from acidified nuclear waste by contacting the waste with a bis 4,4'(5) [1-hydroxy-2-ethylhexyl]benzo 18-crown-6 compound and a cation exchanger in a matrix solution. Strontium is extracted from acidified nuclear waste by contacting the waste with a bis 4,4'(5') [1-hydroxyheptyl]cyclohexo 18-crown-6 compound, and a cation exchanger in a matrix solution.

Designing heat exchangers for process heat reactors

International Nuclear Information System (INIS)

Quade, R.N.

1980-01-01

A brief account is given of the IAEA specialist meeting on process heat applications technology held in Julich, November 1979. The main emphasis was on high temperature heat exchange. Papers were presented covering design requirements, design construction and prefabrication testing, and selected problems. Primary discussion centered around mechanical design, materials requirements, and structural analysis methods and limits. It appears that high temperature heat exchanges design to nuclear standards, is under extensive development but will require a lengthy concerted effort before becoming a commercial reality. (author)

Operating experience with nuclear power plants 2015. Pt. 1

Energy Technology Data Exchange (ETDEWEB)

Anon.

2016-07-01

The VGB Technical Committee ''Nuclear Plant Operation'' has been exchanging operating experience about nuclear power plants for more than 30 years. Plant operators from several European countries are participating in the exchange. A report is given on the operating results achieved in 2015, events important to plant safety, special and relevant repair, and retrofit measures from Germany. The second part of this report will focus on nuclear power plant in Belgium, Finland, the Netherlands, Switzerland, and Spain.

Research of thermal stability of ion exchangers

International Nuclear Information System (INIS)

Stuchlik, S.; Srnkova, J.

1983-01-01

Prior to the fixation of radioactive ion exchangers into bitumen these exchangers have to be dried. The resulting gaseous products may generate explosive mixtures. An analysis was made of the thermal stability of two types of ion exchangers, the cation exchanger KU-2-8 cS and the anion exchanger AV-17-8 cS which are used in the V-1 nuclear power plant at Jaslovske Bohunice. The thermal stability of the anion exchangers was monitored using gas chromatography at temperatures of 100, 120, 140, 160 and 180 degC and by measuring weight loss by kiln-drying at temperatures of 120, 140, 160 and 180 degC. The ion exchanger was heated for 6 hours and samples were taken continuously at one hour intervals. The thermal stability of the cation exchanger was monitored by measuring the weight loss. Gas chromatography showed the release of trimethylamine from the anion exchanger in direct dependence on temperature. The measurement of weight losses, however, only showed higher losses of released products which are explained by the release of other thermally unstable products. The analysis of the thermal stability of the cation exchanger showed the release of SO 2 and the weight loss (following correction for water content) was found only after the fourth hour of decomposition. The experiment showed that the drying of anion exchanger AV-17-8 cS may cause the formation of explosive mixtures. (J.P.)

Joint Thesaurus. Part I (A-L) + Part II (M-Z)[International Nuclear Information System. Energy Technology Data Exchange

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-04-01

This is the 1st revision of the INIS/ETDE Joint Thesaurus. It contains 20 953 valid descriptors and 8 600 forbidden terms. It was last updated in December 2003. The Joint Thesaurus contains the controlled terminology for indexing all information within the subject scope of both INIS (International Nuclear Information System) and ETDE (Energy Technology Data Exchange) information systems. The terminology is intended for use in subject description for input or retrieval of information in those systems. The thesaurus is a terminological control device used in translating from the natural language of documents, indexers or users into a more constrained system language It is also a controlled and dynamic vocabulary of semantically and generically related terms which covers a specific domain of knowledge. The domain of knowledge covered by this Thesaurus includes physics (in particular, plasma physics, atomic and molecular physics, and especially nuclear and high-energy physics), chemistry, materials, earth sciences, radiation biology, radioisotope effects and kinetics, applied life sciences, radiology and nuclear medicine, isotope and radiation source technology, radiation protection, radiation applications, engineering, instrumentation, fossil fuels, synthetic fuels, renewable energy sources, advanced energy systems, fission and fusion reactor technology, safeguards and inspection, waste management, environmental aspects of the production and consumption of energy from nuclear and non-nuclear sources, energy efficiency and energy conservation, economics and sociology of energy production and use, energy policy, and nuclear law. The terms in the Thesaurus are listed alphabetically, and with each alphabetic entry a word block containing the terms associated with the particular entry is displayed. In the word block, terms that have a hierarchical relationship to the entry are identified by the symbols BT and NT, for Broader Term and Narrower Term. Those with an affinitive

A Reappraisal of the Mechanism of Pion Exchange and Its Implications for the Teaching of Particle Physics

Science.gov (United States)

Dunne, Peter

2002-01-01

The origins of the pion exchange model of nuclear forces are described and the exchange process is reinterpreted in the light of current views on the quark-gluon structure of nucleons. It is suggested that the reinterpretation might provide a picture of cohesive nuclear forces that is more intellectually satisfying than that produced by the…

Leak detection for heat exchangers in nuclear facilities

International Nuclear Information System (INIS)

Tsu, D.

1979-01-01

There is added to the secondary circuit 40 Ar, which can be activated. If the heat exchanger to the primary circuit has got a leak 40 Ar will enter the latter and is coverted into 40 Ar in the core of the He-cooled pebble-bed reactor. The gamma activity of 41 Ar is then determined. (DG) [de

Intermediate heat exchanger for HTR process heat application

International Nuclear Information System (INIS)

Crambes, M.

1980-01-01

In the French study on the nuclear gasification of coal, the following options were recommended: Coal hydrogenation, the hydrogen being derived from CH 4 reforming under the effects of HTR heat; the use of an intermediate helium circuit between the nuclear plant and the reforming plant. The purpose of the present paper is to describe the heat exchanger designed to transfer heat from the primary to the intermediate circuit

Thermal studies on some new inorganic exchange materials

International Nuclear Information System (INIS)

Murthy, G.S.; Satyanarayana, J.; Reddy, V.N.

1998-01-01

The new inorganic exchangers developed in this laboratory zirconium phosphate-ammonium molybdophosphate (ZrP-AMP), titanium phosphate-ammonium molybdophosphate (TiP-AMP) and alumina-ammonium molybdophosphate (alumina-AMP) have been investigated extensively to study the removal of Cs from high level nuclear waste. As a part of these studies thermal studies on these substances have been carried out to elucidate the information on thermal stability of these exchangers. Results obtained are presented here and discussed. (author)

EXFOR Basics. A short guide to the neutron reaction data exchange format

International Nuclear Information System (INIS)

McLane, V.; NUCLEAR DATA CENTER NETWORK

2000-01-01

This manual is intended as a guide to users of nuclear reaction data compiled in the EXFOR format, and is not intended as a complete guide to the EXFOR System. EXFOR is the exchange format designed to allow transmission of nuclear reaction data between the Nuclear Reaction Data Centers. In addition to storing the data and its' bibliographic information, experimental information is also compiled. The status (e.g., the source of the data) and history (e.g., date of last update) of the data set is also included. EXFOR is designed for flexibility in order to meet the diverse needs of the nuclear reaction data centers. It was originally conceived for the exchange of neutron data and was developed through discussions among personnel from centers situated in Saclay, Vienna, Livermore and Brookhaven. It was accepted as the official exchange format of the neutron data centers at Saclay, Vienna, Brookhaven and Obninsk, at a meeting held in November 1969.3 As a result of two meetings held in 1975 and 1976 and attended by several charged-particle data centers, the format was further developed and adapted to cover all nuclear reaction data. The exchange format should not be confused with a center-to-user format. Although users may obtain data from the centers in the EXFOR format, other center-to-user formats have been developed to meet the needs of the users within each center's own sphere of responsibility. The EXFOR format, as outlined, allows a large variety of numerical data tables with explanatory and bibliographic information to be transmitted in a format: l that is machine-readable (for checking and indicating possible errors); l that can be read by personnel (for passing judgment on and correcting errors). The data presently included in the EXFOR exchange file include: a complete compilation of experimental neutron-induced reaction data, a selected compilation of charged-particle-induced reaction data, a selected compilation of photon-induced reaction data

Major heat exchanger performance in Ontario Hydro-operated CANDU nuclear generating stations

International Nuclear Information System (INIS)

Dueck, D.G.

1980-01-01

The performance of heat exchangers is described in terms of their impact on the unit in the form of forced outages and deratings as well as incapability due to scheduled outages. Some major problems with heat exchangers are highlighted. (auth)

A methodology for determining the dynamic exchange of resources in nuclear fuel cycle simulation

Energy Technology Data Exchange (ETDEWEB)

Gidden, Matthew J., E-mail: gidden@iiasa.ac.at [International Institute for Applied Systems Analysis, Schlossplatz 1, A-2361 Laxenburg (Austria); University of Wisconsin – Madison, Department of Nuclear Engineering and Engineering Physics, Madison, WI 53706 (United States); Wilson, Paul P.H. [University of Wisconsin – Madison, Department of Nuclear Engineering and Engineering Physics, Madison, WI 53706 (United States)

2016-12-15

Highlights: • A novel fuel cycle simulation entity interaction mechanism is proposed. • A framework and implementation of the mechanism is described. • New facility outage and regional interaction scenario studies are described and analyzed. - Abstract: Simulation of the nuclear fuel cycle can be performed using a wide range of techniques and methodologies. Past efforts have focused on specific fuel cycles or reactor technologies. The CYCLUS fuel cycle simulator seeks to separate the design of the simulation from the fuel cycle or technologies of interest. In order to support this separation, a robust supply–demand communication and solution framework is required. Accordingly an agent-based supply-chain framework, the Dynamic Resource Exchange (DRE), has been designed implemented in CYCLUS. It supports the communication of complex resources, namely isotopic compositions of nuclear fuel, between fuel cycle facilities and their managers (e.g., institutions and regions). Instances of supply and demand are defined as an optimization problem and solved for each timestep. Importantly, the DRE allows each agent in the simulation to independently indicate preference for specific trading options in order to meet both physics requirements and satisfy constraints imposed by potential socio-political models. To display the variety of possible simulations that the DRE enables, example scenarios are formulated and described. Important features include key fuel-cycle facility outages, introduction of external recycled fuel sources (similar to the current mixed oxide (MOX) fuel fabrication facility in the United States), and nontrivial interactions between fuel cycles existing in different regions.

A methodology for determining the dynamic exchange of resources in nuclear fuel cycle simulation

International Nuclear Information System (INIS)

Gidden, Matthew J.; Wilson, Paul P.H.

2016-01-01

Highlights: • A novel fuel cycle simulation entity interaction mechanism is proposed. • A framework and implementation of the mechanism is described. • New facility outage and regional interaction scenario studies are described and analyzed. - Abstract: Simulation of the nuclear fuel cycle can be performed using a wide range of techniques and methodologies. Past efforts have focused on specific fuel cycles or reactor technologies. The CYCLUS fuel cycle simulator seeks to separate the design of the simulation from the fuel cycle or technologies of interest. In order to support this separation, a robust supply–demand communication and solution framework is required. Accordingly an agent-based supply-chain framework, the Dynamic Resource Exchange (DRE), has been designed implemented in CYCLUS. It supports the communication of complex resources, namely isotopic compositions of nuclear fuel, between fuel cycle facilities and their managers (e.g., institutions and regions). Instances of supply and demand are defined as an optimization problem and solved for each timestep. Importantly, the DRE allows each agent in the simulation to independently indicate preference for specific trading options in order to meet both physics requirements and satisfy constraints imposed by potential socio-political models. To display the variety of possible simulations that the DRE enables, example scenarios are formulated and described. Important features include key fuel-cycle facility outages, introduction of external recycled fuel sources (similar to the current mixed oxide (MOX) fuel fabrication facility in the United States), and nontrivial interactions between fuel cycles existing in different regions.

Efforts in improvement of nuclear knowledge and information management in Croatia

International Nuclear Information System (INIS)

Pleslic, S.; Novosel, N.

2005-01-01

The IAEA was authorised for exchange of technical and scientific information on peaceful uses of atomic energy and established INIS in 1970 as an international bibliographic database in the nuclear field and in nuclear related areas. Countries at different levels of technological development could derive benefits from INIS output products. The use of nuclear technology relies on the accumulation of knowledge in nuclear science and technology, including both technical information in documents and databases, and knowledge in human resources. Nuclear knowledge and information exchange are important for the process of decision-making. The IAEA supports all Members in systematic knowledge preservation and information exchange, who want to transfer their practical experience to the younger generation and to archive important information. Croatia is involved in activities in knowledge and information management since 1994 when she joined INIS. Thanks to development and application of new information technologies within the INIS information management framework, Members improve the collection, production and dissemination of nuclear knowledge and information. (author)

Assessment of ASME code examinations on regenerative, letdown and residual heat removal heat exchangers

International Nuclear Information System (INIS)

Gosselin, Stephen R.; Cumblidge, Stephen E.; Anderson, Michael T.; Simonen, Fredric A.; Tinsley, G A.; Lydell, B.; Doctor, Steven R.

2005-01-01

Inservice inspection requirements for pressure retaining welds in the regenerative, letdown, and residual heat removal heat exchangers are prescribed in Section XI Articles IWB and IWC of the ASME Boiler and Pressure Vessel Code. Accordingly, volumetric and/or surface examinations are performed on heat exchanger shell, head, nozzle-to-head, and nozzle-to-shell welds. Inspection difficulties associated with the implementation of these Code-required examinations have forced operating nuclear power plants to seek relief from the U.S. Nuclear Regulatory Commission. The nature of these relief requests are generally concerned with metallurgical, geometry, accessibility, and radiation burden. Over 60% of licensee requests to the NRC identify significant radiation exposure burden as the principle reason for relief from the ASME Code examinations on regenerative heat exchangers. For the residual heat removal heat exchangers, 90% of the relief requests are associated with geometry and accessibility concerns. Pacific Northwest National Laboratory was funded by the NRC Office of Nuclear Regulatory Research to review current practice with regard to volumetric and/or surface examinations of shell welds of letdown heat exchangers regenerative heat exchangers and residual (decay) heat removal heat exchangers Design, operating, common preventative maintenance practices, and potential degradation mechanisms are reviewed. A detailed survey of domestic and international PWR-specific operating experience was performed to identify pressure boundary failures (or lack of failures) in each heat exchanger type and NSSS design. The service data survey was based on the PIPExp- database and covers PWR plants worldwide for the period 1970-2004. Finally a risk assessment of the current ASME Code inspection requirements for residual heat removal, letdown, and regenerative heat exchangers is performed. The results are then reviewed to discuss the examinations relative to plant safety and

Intermediate energy nuclear physics (Task C) and charge exchange reactions (Task W). Technical progress report, October 1, 1985-October 1, 1986

International Nuclear Information System (INIS)

Kraushaar, J.J.

1986-10-01

This report describes the experimental work in intermediate energy research carried out over the past year at the University of Colorado. The experimental program is very broad in nature, ranging from investigations in pion-nucleus interactions, nucleon charge exchange, inelastic electron scattering, and nucleon transfer reactions. The experiments were largely carried out at the Los Alamos Meson Physics Facility, but important programs were conducted at the Tri-University Meson Facility at the University of British Columbia, the Indiana University Cyclotron Facility and Netherlands Institute for Nuclear Physics Research (NIKHEF-K)

Sister-chromatid exchanges in nuclear fuel workers

International Nuclear Information System (INIS)

Prabhavathi, P. Aruna; Fatima, Shehla K.; Padmavathi, P.; Kumari, C. Kusuma; Reddy, P.P.

1995-01-01

Peripheral blood lymphocyte cultures of 116 smokers and 80 non-smokers who were occupationally exposed to uranyl compounds were analysed for sister-chromatid exchanges (SCEs). Blood samples were collected from 59 non-smokers (control group I) and 47 smokers (control group II) who were not exposed to uranium for control data. A significant increase in SCEs was observed among both smokers and non-smokers exposed to uranyl compounds when compared to their respective controls. In controls, a significant increase in the frequency of SCEs was observed in smokers when compared to non-smokers

Nuclear winter: Global consequences of multiple nuclear explosions

International Nuclear Information System (INIS)

Turco, R.P.; Toon, O.B.; Ackerman, T.P.; Pollack, J.B.; Sagan, C.

1984-01-01

Concern has been raised over the short- and long-term consequences of the dust, smoke, radioactivity, and toxic vapors that would be generated by a nuclear war. The discovery that dense clouds of soil particles may have played a major role in past mass extinctions of life on Earth has encouraged the reconsideration of nuclear war effects. These developments have led the authors to calculate, using new data and improved models, the potential global environmental effects of dust and smoke clouds (henceforth referred to as nuclear dust and smoke) generated in a nuclear war. They neglect the short-term effects of blast, fire, and radiation. Most of the world's population could probably survive the initial nuclear exchange and would inherit the postwar environment. Accordingly, the longer-term and global-scale aftereffects of nuclear war might prove to be as important as the immediate consequences of the war

Trend of development of robots for nuclear facilities

International Nuclear Information System (INIS)

Maki, Hideo; Sasaki, Masayoshi

1984-01-01

Robot technology becomes more and more important in the field of atomic energy industries. Hitachi Ltd. has energetically engaged in the development of the robot technology for nuclear facilities, recognizing these situations. The course of the development of robot technology and the robots for nuclear facilities is described. As the practical examples of the robots for nuclear facilities, there have been automatic fuel exchangers, the remotely operated automatic exchangers for control rod driving mechanism, automatic and semi-automatic ultrasonic flaw detectors and so on. As the robots for nuclear facilities under development, control rod driving mechanism disassembling and cleaning system, the volume reduction device for spent fuel channel boxes and control rods and others are reported. (Kako, I.)

Application of the Guided Wave Technique to the Heat Exchanger Tube in NPP

International Nuclear Information System (INIS)

Yang, Dong Soon; Kim, Hyung Nam; Yoo, Hyun Joo

2005-01-01

The heat exchanger tube is examined by the method of eddy current test(ECT) to identify the integrity of the nuclear power plant. Because ECT probe is moved through the tube inside to identify flaws, the ECT probe should be exchanged periodically due to the wear of probe surface in order to remove the noise form the ECT signal. Moreover, it is impossible to examine the tube by ECT method because the ECT probe can not move through the inside due to the deformation such as dent. Recently, the theory of guided wave was established and the equipment applying the theory has been actively developed so as to overcome the limitation of ECT method for the tube inspection of heater exchanger in nuclear power plant. The object of this study is to know the application of the guided wave technique to heat exchanger tube in NPP

Thermal hydraulic simulation of moderator heat exchanger

International Nuclear Information System (INIS)

Anil Lal, S.; Rajakumar, A.; Vaidyanathan, G.; Srinivasan, R.; Chetal, S.C.

1993-01-01

Pressurized heavy water reactors form the majority in the first stage of India's nuclear power programme. Heavy water is both moderator and primary coolant. The heat generated in the moderator due to neutron moderation and capture has to be removed in moderator heat exchangers. It has been desired to improve the performance characteristics of moderator heat exchangers, whereby moderator would enter the calandria vessel at a low temperature and would enable higher power of operation for the same limiting temperature of moderator in the calandria. Results of studies carried out using a three dimensional computer code for various operating options are given. Using these velocities the heat exchangers have been analysed for flow induced vibrations. 7 refs., 6 figs., 6 tabs

Exchanging information

International Nuclear Information System (INIS)

1971-01-01

The Agency has a statutory mandate to foster 'the exchange of scientific and technical information on the peaceful uses of atomic energy'. The prime responsibility for this work within the Agency lies with the Division of Scientific and Technical Information, a part of the Department of Technical Operations. The Division accomplishes its task by holding conferences and symposia (Scientific Conferences Section), through the Agency Library, by publishing scientific journals, and through the International Nuclear Information System (INIS). The Computer Section of the Division, which offers services to the Agency as a whole, provides resources for the automation of data storage and retrieval. (author)

On-Line Monitoring and Diagnostics of the Integrity of Nuclear Plant Steam Generators and Heat Exchangers, Volumes 1, 2

Energy Technology Data Exchange (ETDEWEB)

Upadhyaya, Belle R. [Univ. of Tennessee, Knoxville, TN (United States); Hines, J. Wesley [Univ. of Tennessee, Knoxville, TN (United States); Lu, Baofu [Univ. of Tennessee, Knoxville, TN (United States)

2005-06-03

The overall purpose of this Nuclear Engineering Education Research (NEER) project was to integrate new, innovative, and existing technologies to develop a fault diagnostics and characterization system for nuclear plant steam generators (SG) and heat exchangers (HX). Issues related to system level degradation of SG and HX tubing, including tube fouling, performance under reduced heat transfer area, and the damage caused by stress corrosion cracking, are the important factors that influence overall plant operation, maintenance, and economic viability of nuclear power systems. The research at The University of Tennessee focused on the development of techniques for monitoring process and structural integrity of steam generators and heat exchangers. The objectives of the project were accomplished by the completion of the following tasks. All the objectives were accomplished during the project period. This report summarizes the research and development activities, results, and accomplishments during June 2001 September 2004. Development and testing of a high-fidelity nodal model of a U-tube steam generator (UTSG) to simulate the effects of fouling and to generate a database representing normal and degraded process conditions. Application of the group method of data handling (GMDH) method for process variable prediction. Development of a laboratory test module to simulate particulate fouling of HX tubes and its effect on overall thermal resistance. Application of the GMDH technique to predict HX fluid temperatures, and to compare with the calculated thermal resistance.Development of a hybrid modeling technique for process diagnosis and its evaluation using laboratory heat exchanger test data. Development and testing of a sensor suite using piezo-electric devices for monitoring structural integrity of both flat plates (beams) and tubing. Experiments were performed in air, and in water with and without bubbly flow. Development of advanced signal processing methods using

Automatic fuel exchanging device

International Nuclear Information System (INIS)

Takahashi, Fuminobu.

1984-01-01

Purpose: To enable to designate the identification number of a fuel assembly in a nuclear reactor pressure vessel thereby surely exchanging the designated assembly within a short time. Constitution: Identification number (or letter) pressed on a grip of a fuel assembly is to be detected by a two-dimensional ultrasonic probe of a pull-up mechanism. When the detected number corresponds with the designated number, a control signal is outputted, whereby the pull-up drive control mechanism or pull-up mechanism responds to pull-up and exchange the fuel assembly of the identified number. With such a constitution, the fuel assembly can rapidly and surely be recognized even if pressed letters deviate to the left or right of the probe, and further, the hinge portion and the signal processing portion can be simplified. (Horiuchi, T.)

European Nuclear Features

International Nuclear Information System (INIS)

Barre, B.; Gonzalez, E.; Diaz Diaz, J.L.; Jimenez, J.L.; Velarde, G.; Navarro, J.M.; Hittner, D.; Dominguez, M.T.; Bollini, G.; Martin, A.; Suarez, J.; Traini, E.; Lang-Lenton, J.

2004-01-01

''European Nuclear Features - ENF'' is a joint publication of the three specialized technical journals, Nuclear Espana (Spain), Revue General Nucleaire (France), and atw - International Journal of Nuclear Power (Germany). The ENF support the international Europeen exchange of information and news about energy and nuclear power. News items, comments, and scientific and technical contributions will cover important aspects of the field. The second issue of ENF contains contributions about theses topics, among others: Institutional and Political Changes in the EU. - CIEMAT Department of Nuclear Fission: A General Overview. - Inertial Fusion Energy at DENIM. - High Temperature Reactors. European Research Programme. - On Site Assistance to Khmelnitsky NPP 1 and 2 (Ukraine). - Dismantling and Decommissioning of Vandellos I. (orig.)

Nuclear Symbiosis - A Means to Achieve Sustainable Nuclear Growth While Limiting the Spread of Sensitive Nuclear Technology

International Nuclear Information System (INIS)

Shropshire, David

2009-01-01

Global growth of nuclear energy in the 21. century is creating new challenges to limit the spread of nuclear technology without hindering adoption in countries now considering nuclear power. Independent nuclear states desire autonomy over energy choices and seek energy independence. However, this independence comes with high costs for development of new indigenous fuel cycle capabilities. Nuclear supplier states and expert groups have proposed fuel supply assurance mechanisms such as fuel take-back services, international enrichment services and fuel banks in exchange for recipient state concessions on the development of sensitive technologies. Recipient states are slow to accept any concessions to their rights under the Non Proliferation Treaty. To date, decisions to not develop indigenous fuel enrichment capabilities have been driven by economics. However, additional incentives may be required in the future to offset the user state's perceived loss of energy independence. In order for a country to forgo development of sensitive nuclear capabilities, the basis for an equitable economic tradeoff must be established. This paper proposes that the nuclear trade-off can be made through a combination of fuel supply assurances, leveraging work by the United Nations and International Atomic Energy Agency on sustainable nuclear development, and use of 'nuclear symbiosis'. The primary focus of this paper is on how nuclear symbiosis could be used to achieve a user-state's desired economic, energy, and infrastructure development end states. The desired result from this 'symbiosis' is a nuclear-centered industrial complex that creates new economic opportunities through infrastructure improvements, human resource skills development and the development of new sustainable industries. This paper also describes the Nuclear Materials Exchange (NME) as a practical tool for performing nuclear symbiosis. The NME can be used to define existing and new international nuclear resources and

Proceedings of the 9. National Seminar on Technology and Safety of Nuclear Power Plants and Nuclear Facilities

International Nuclear Information System (INIS)

Antariksawan, Anhar R.; Soetrisnanto, Arnold Y; Aziz, Ferhat; Untoro, Pudji; Su'ud, Zaki; Zarkasi, Amin Santoso; Lasman, As Natio

2003-08-01

The ninth proceedings of seminar safety and technology of nuclear power plant and nuclear facilities held by National Nuclear Energy Agency and PLN-JTK. The aims of seminar is to exchange and disseminate information about Safety and Nuclear Power Plant Technology and Nuclear Facilities consist of Technology High Temperature Reactor and Application for National Development Sustainable and High Technology. This seminar cover all aspects Technology, Power Reactor, Research Reactor High Temperature Reactor and Nuclear Facilities. There are 20 articles have separated index

A Method to Establishing Tube Plugging Criterion for Heat Exchangers with Straight Tubes

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyungnam [KHNP CRI, Daejeon (Korea, Republic of)

2016-10-15

The difference of thermal expansion coefficients between the shell and tube materials causes the stress in axial direction of tube. Because of the axial stress due to thermal load, the straight tubes are used for heat exchangers operated in low temperature such as CCW (Component Cooling Water) heat exchangers and condensers. It is inevitable for the materials of the components to be degraded as the power plants become older. The degradation accompanies increasing maintenance cost as well as creating safety issues. The materials and wall thickness of heat exchanger tubes in nuclear power plants are selected to withstand system temperature, pressure, and corrosion. There are many codes and standards to be referred for calculating the minimum thickness of the heat exchanger tube in the designing stage. However, the codes and standards related to show the tube plugging criteria may not exist currently. In this paper, a method to establish the tube plugging criteria of BOP heat exchangers, which is based on the USNRC Regulatory Guide 1.121, is introduced and the tube plugging criteria for the TPCCW heat exchanger of Yonggwang NPP No. 1 and 2. A method to establish the tube plugging criteria of heat exchangers with straight tubes are introduced based on the USNRC Regulatory Guide 1.121. As an example, the tube plugging criterion for the CCW heat exchanger of a nuclear power plant is provided.

Performances of nuclear installations in the world

International Nuclear Information System (INIS)

Pate, Z.T.

1999-01-01

During the last years the operators of nuclear power plants in the world, have realized numerous improvements. This success is imputable to several factors, especially an important data exchange. The Chernobyl accident, in 1986, provoked the creation of the World Association of Nuclear Operators (W.A.N.O.). It allowed to exchange information and to develop cooperation in order to go beyond cultural barriers, linguistics and policies. Then, operators in the world have brought important improvements in matter of safety, reliability. (N.C.)

Damping of multispan heat exchanger tubes. Pt. 1: in gases

International Nuclear Information System (INIS)

Pettigrew, M.J.; Goyder, H.G.D.; Qiao, Z.L.; Axisa, F.

1986-07-01

Flow-induced vibration analyses of heat exchanger tubes require the knowledge of damping. This paper treats the question of damping on multispan heat exchanger tubes in air and gases. The different energy dissipation mechanisms that contribute to tube damping are discussed. The available experimental data are reviewed and analysed. We find that the main damping mechanism in gases is friction between tube and tube-supports. Damping is strongly related to tube-support thickness. Damping values are recommended for design purposes. This study is interesting in the nuclear industry for it often uses heat exchangers

Management of spent ion-exchange resins from nuclear power plants

International Nuclear Information System (INIS)

1981-01-01

Information presented at the IAEA organized Technical Committee Meeting in December 1976 is given on the management of spent ion-exchange resins with respect to their treatment and conditioning. Currently available processes, methods and technologies such as volume reduction techniques, immobilization techniques, etc. for the treatment and conditioning are described on the basis of operating experiences. Economic aspects associated with the use, treatment, packaging and disposal of ion-exchange resins are dealt with the purpose to serve as an example of an appropriate economic evaluation. The current and prospective status of the resin disposal in USA, France, Federal Republic of Germany, United Kingdom and India is briefly discussed

Method of processing spent ion exchange resins

International Nuclear Information System (INIS)

Mori, Kazuhide; Tamada, Shin; Kikuchi, Makoto; Matsuda, Masami; Aoyama, Yoshiyuki.

1985-01-01

Purpose: To decrease the amount of radioactive spent ion exchange resins generated from nuclear power plants, etc and process them into stable inorganic compounds through heat decomposition. Method: Spent ion exchange resins are heat-decomposed in an inert atmosphere to selectively decompose only ion exchange groups in the preceeding step while high molecular skeltons are completely heat-decomposed in an oxidizing atmosphere in the succeeding step. In this way, gaseous sulfur oxides and nitrogen oxides are generated in the preceeding step, while gaseous carbon dioxide and hydrogen requiring no discharge gas procession are generated in the succeeding step. Accordingly, the amount of discharged gases requiring procession can significantly be reduced, as well as the residues can be converted into stable inorganic compounds. Further, if transition metals are ionically adsorbed as the catalyst to the ion exchange resins, the ion exchange groups are decomposed at 130 - 300 0 C, while the high molecular skeltons are thermally decomposed at 240 - 300 0 C. Thus, the temperature for the heat decomposition can be lowered to prevent the degradation of the reactor materials. (Kawakami, Y.)

Overhaul of the heat exchanger in JRR-3

International Nuclear Information System (INIS)

Ouchi, Yasuhiro; Kawamata, Satoshi; Taguchi, Yuji; Kamiishi, Eigo; Koda, Nobuyuki

2013-01-01

In JRR-3, heat exchangers are installed in the cooling system equipment to remove the heat generated in the nuclear reactor, For the heat exchangers, overhaul inspection based on the JRR-3 reactor facility maintenance plan, as well as the inspection and maintenance based on reactor facility security provisions and JRR-3 operation guidelines are systematically conducted. Considering the results of overhaul inspection, the second overhaul inspection was applied to the primary coolant heat exchanger. The thinning of heat transfer tubes is within judgment standards with little effects of aging, which verified their soundness. From the fact that the effects of corrosion have been confirmed on the inside of the water chamber, repair work through overlay welding or the like is planned in the next overhaul. As for heavy water heat exchanger and the spent fuel pool water heat exchanger, it is planned to conduct the second overhaul inspection in FY2013 to confirm their soundness. (A.O.)

Improvement of incineration efficiency of spent ion exchange resins on the incinerator at nuclear power plants. Manufacturing the solids of the resins mixed with paraffin wax and their incinerating test results on actual incinerator

International Nuclear Information System (INIS)

Izumi, Takeshi; Ohtsu, Takashi; Inagawa, Hirofumi; Kawakami, Takashi; Hagiwara, Masahiro; Ino, Takao; Ishiyama, Yuji

2011-01-01

In nuclear power plants, ion exchange resins are used at water purification systems such as condensate demineralizers. After usage, used ion exchange resins are stored at plants as low level radioactive wastes. Ion exchange resins contain water and so, those are flame resistant materials. At present, ion exchange resins are incinerated with other inflammable materials at incinerators. Furthermore, ion exchange resins are fine particle beads and are easy to be scattered in all directions, so operators must pay attentions for treatment. Then, we have developed the new solidification system of ion exchange resins with paraffin wax. Ion exchange resins are mixed and extruded with paraffin wax and these solids are enabled to incinerate at existing incinerators. In order to demonstrate this new method, we made the large amount of solids and incinerated them at actual incinerator. From these results, we have estimated to be able to incinerate the solids only at actual incinerator. (author)

Ion exchange filter transition plan for BWRs and PWRs

International Nuclear Information System (INIS)

Garcia, Susan; McElrath, Joel; Varnam, Jeremie; Giannelli, Joseph F.

2014-01-01

Analysis and quantification of reactor water, feedwater, and chemical and volume control system (CVCS) soluble metals and radioisotopes are essential for monitoring species that impact fuel performance, steam generator and heat exchanger performance, mitigation of stress corrosion cracking of reactor piping and internals, radiation fields and ensuring that dose mitigation techniques are effective. Soluble species in the CVCS, feedwater, reactor water and other process sample streams are usually collected on ion exchange membranes after the sample has passed through a 0.45 or 0.1 μm membrane filter. Cationic species are predominantly of interest. Most nuclear plants currently use cation exchange membranes from Toray Industries, Inc. In September 2012, it was reported that Toray Industries, Inc. would discontinue the manufacturing of cation exchange membranes at the end of 2012. Similar reports were received concerning ion exchange membranes manufactured by Pall Corporation. These reports prompted several plants and utilities to begin evaluating other products from various vendors to replace their current ion exchange membranes in preparation for a transition. With this possible change having a potential impact on the water chemistry analyses that are important for monitoring fuel reliability and corrosion and dose control, an initial scoping evaluation of ion exchange membrane availability from various vendor and plant experiences was conducted. Recommended approaches were provided to close identified gaps and reduce burden on nuclear plant chemistry laboratories. Additional work required in 2014, includes an independent laboratory review of membrane performance and in-plant demonstrations. These demonstrations and evaluations will assist the industry by providing the technical input needed to manage a change in membrane use so that preferred processes and media can be identified to minimize any adverse impacts on chemistry analyses that support chemistry control

Coming to grips with nuclear winter

International Nuclear Information System (INIS)

Scherr, S.J.

1985-01-01

This editorial examines the politics related to the concept of nuclear winter which is a term used to describe temperature changes brought on by the injection of smoke into the atmosphere by the massive fires set off by nuclear explosions. The climate change alone could cause crop failures and lead to massive starvation. The author suggests that the prospect of a nuclear winter should be a deterrent to any nuclear exchange

INDC correspondents for the exchange of nuclear data information

International Nuclear Information System (INIS)

1980-05-01

This list serves as a basis for the distribution of documents originated by or for the International Nuclear Data Committee and includes the names of all recipients of INDC documents. The INDC Secretariat tries to maintain this list up-to-date in order to facilitate an efficient interchange of information on nuclear data topics

INDC correspondents for the exchange of nuclear data information

International Nuclear Information System (INIS)

1979-05-01

This list serves as a basis for the distribution of documents originated by or for the International Nuclear Data Committee and includes the names of all recipients of INDC documents. The INDC Secretariat tries to maintain this list up-to-date in order to facilitate an efficient interchange of information on nuclear data topics

Selected topics in nuclear structure

Energy Technology Data Exchange (ETDEWEB)

Solov` ev, V G; Gromov, K Ya; Malov, L A; Shilov, V M

1994-12-31

The Fourth International Conference on selected topics in nuclear structure was held at Dubna in July 1994 on recent experimental and theoretical investigations in nuclear structure. Topics discussed were the following: nuclear structure at low-energy excitations (collective quasiparticle phenomena, proton-neutron interactions, microscopic and phenomenological theories of nuclear structure; nuclear structure studies with charged particles). heavy ions, neutrons and photons; nuclei at high angular momenta and superdeformation, structure and decay properties of giant resonances, charge-exchange resonances and {beta}-decay; semiclassical approach of large amplitude collective motion and structure of hot nuclei.

Selected topics in nuclear structure

International Nuclear Information System (INIS)

Solov'ev, V.G.; Gromov, K.Ya.; Malov, L.A.; Shilov, V.M.

1994-01-01

The Fourth International Conference on selected topics in nuclear structure was held at Dubna in July 1994 on recent experimental and theoretical investigations in nuclear structure. Topics discussed were the following: nuclear structure at low-energy excitations (collective quasiparticle phenomena, proton-neutron interactions, microscopic and phenomenological theories of nuclear structure; nuclear structure studies with charged particles. heavy ions, neutrons and photons; nuclei at high angular momenta and superdeformation, structure and decay properties of giant resonances, charge-exchange resonances and β-decay; semiclassical approach of large amplitude collective motion and structure of hot nuclei

Exchange Reactions. Proceedings of the Symposium on Exchange Reactions

International Nuclear Information System (INIS)

1965-01-01

The mechanisms and kinetics of chemical reactions are of great interest to chemists. The study of exchange reactions in particular helps to shed light on the dynamics of chemical change, providing an insight into the structures and the reactivities of the chemical species involved. The main theme of this meeting was the subject of oxidation-reduction reactions in which the net result is the transfer of one or more electrons between the different oxidation states of the same element. Other studies reported included the transfer of protons, atoms, complex ligands or organic radicals between molecules. Heterogeneous exchange, which is of importance in many cases of catalytic action, was also considered. For a long time isotopic tracers have formed the most convenient means of studying exchange reactions and today a considerable amount of work continues to be done with their aid. Consequently, several papers presented at this Symposium reported on work carried out by purely radiochemical tracer methods. In recognition, however, of the important role which nuclear magnetic resonance and electron spin resonance play in this field, in particular in the study of fast reactions, a number of reports on investigations in which these techniques had been used was included in the programme. By kind invitation of the United States Government the Symposium on Exchange Reactions was held from 31 May to 4 June at the Brookhaven National Laboratory, Upton, Long Island, N.Y., USA. It was attended by 46 participants from nine countries and one inter-governmental organization. The publication of these Proceedings makes the contents of the papers and the discussion available to a wider audience

An advanced straight tube heat exchanger in which a fluid flows at variable and elevated temperatures

International Nuclear Information System (INIS)

Mauget, C.; Benoit, G.; Stalport, G.

1993-01-01

Straight tube heat exchangers are used as steam generators in nuclear reactors such as in fast neutron nuclear power plants; elevated and highly variable temperatures induce very high thermal expansion constraints in these long straight tubes. In order to avoid the expansion problems, an expansion bellow is disposed between the heat exchanger and the collector tubular plate in such a way that the bundle differential expansions may be absorbed

The radioactive inventory of a Berkeley heat exchanger

International Nuclear Information System (INIS)

Hancock, R.

1988-10-01

The Central Electricity Generating Board has announced a date for the final shutdown of the first of the Magnox power stations at Berkeley (March 1989), and is in the process of preparing Pre-Decommissioning Safety Reports (PDSR) for the decommissioning of Berkeley and Bradwell. This report supports these PDSR studies and reports work carried out within the Research Division at Berkeley Nuclear Laboratories on the radioactive inventories of the heat exchangers at Berkeley Power Station. At Berkeley, the heat exchangers will be included in stage two decommissioning to which they will contribute the largest mass of contaminated material. The purpose of this report is to bring together all of the available data on the contamination in the heat exchangers at Berkeley Power Station, and to recommend a database from which the options for disposal of the heat exchangers may be formulated. (author)

Prediction of Heat Removal Capacity of Horizontal Condensation Heat Exchanger submerged in Pool

Energy Technology Data Exchange (ETDEWEB)

Jeon, Seong-Su; Hong, Soon-Joon [FNC Tech., Yongin (Korea, Republic of); Cho, Hyoung-Kyu [Seoul National University, Seoul (Korea, Republic of); Park, Goon-Cherl [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

2014-10-15

As representative passive safety systems, there are the passive containment cooling system (PCCS) of ESBWR, the emergency condenser system (ECS) of the SWR-1000, the passive auxiliary feed-water system (PAFS) of the APR+ and etc. During the nuclear power plant accidents, these passive safety systems can cool the nuclear system effectively via the heat transfer through the steam condensation, and then mitigate the accidents. For the optimum design and the safety analysis of the passive safety system, it is essential to predict the heat removal capacity of the heat exchanger well. The heat removal capacity of the horizontal condensation heat exchanger submerged in a pool is determined by a combination of a horizontal in-tube condensation heat transfer and a boiling heat transfer on the horizontal tube. Since most correlations proposed in the previous nuclear engineering field were developed for the vertical tube, there is a certain limit to apply these correlations to the horizontal tube. Therefore, this study developed the heat transfer model for the horizontal Ushaped condensation heat exchanger submerged in a pool to predict well the horizontal in-tube condensation heat transfer, the boiling heat transfer on the horizontal tube and the overall heat removal capacity of the heat exchanger using the best-estimate system analysis code, MARS.

The role of the Pauli principle in metastability exchange collisions

International Nuclear Information System (INIS)

Pinard, M.; Laloe, F.

1980-01-01

In optical pumping experiments, metastability exchange collisions are used to transfer orientation, alignment, ... between different atomic levels. This article studies the effect of such collisions on the atom internal variables density operator by a method used in a previous publication for spin exchange collisions. The calculations are valid when the nuclei of the two atoms are distinguishable as well as when they are identical particles, wich allows a detailed discussion of nuclear identity effects (apparent magnetic field, etc...). Two cases are successively studied: no depolarization of the electronic angular momentum (He*-He collisions) and partial depolarization (Ne*-Ne collisions for example). The nuclear identity effects should be observable in low temperature optical pumping experiments with noble gases. In an Appendix, another particle identity effect is studied, which can be observed in atomic beam experiments: during the collision of two 3 He atoms, both in the ground state, the spin state of the atoms scattered in a particular direction can be changed by nuclear indistinguishability effects

Nuclear reactions an introduction

CERN Document Server

Paetz gen. Schieck, Hans

2014-01-01

Nuclei and nuclear reactions offer a unique setting for investigating three (and in some cases even all four) of the fundamental forces in nature. Nuclei have been shown – mainly by performing scattering experiments with electrons, muons, and neutrinos – to be extended objects with complex internal structures: constituent quarks; gluons, whose exchange binds the quarks together; sea-quarks, the ubiquitous virtual quark-antiquark pairs and, last but not least, clouds of virtual mesons, surrounding an inner nuclear region, their exchange being the source of the nucleon-nucleon interaction.   The interplay between the (mostly attractive) hadronic nucleon-nucleon interaction and the repulsive Coulomb force is responsible for the existence of nuclei; their degree of stability, expressed in the details and limits of the chart of nuclides; their rich structure and the variety of their interactions. Despite the impressive successes of the classical nuclear models and of ab-initio approaches, there is clearly no ...

Introducing a European Partnership. First issue of 'European Nuclear Features'. A joint publication of atw, Nuclear Espana, Revue Generale Nucleare (2004)

International Nuclear Information System (INIS)

2004-01-01

'European Nuclear Features' is a joint publication of the three specialized technical journals, Nuclear Espana (Spain), Revue Generale Nucleaire (France), and atw - International Journal for Nuclear Power (Germany), planned for six issues annually. ENF is to further greatly the international European exchange of information and news about energy and nuclear power. News items, comments, and scientific and technical contributions will cover important aspects of the field. The first issue of ENF contains contributions about these topics, among others: - European Nuclear Society and Foratom: Strengthening the Nuclear Network. - Report: EPR - the European Pressurized Water Reactor. - Finland: Starting Construction of the Fifth Nuclear Power Plant. - Czech Republic: Nuclear Power Report for 2003/2004. - The Decommissioning Project of the Bohunice-1 and -2 Units. - FRM-II: TUM Research Neutron Source Generates Its First Neutrons. (orig.)

The Ontario Hydro approach to assuring quality in nuclear heat exchanger tubing

International Nuclear Information System (INIS)

Maka, E.P.

1982-01-01

Ontario Hydro utilizes the CANDU PHWR reactor system. The heat transport system circulates pressurized heavy water through the reactor fuel channels to remove heat produced by the fission of uranium fuel. Heavy water is used for the heat transport medium because it is the most efficient liquid from the standpoint of neutron economy. The heat is carried by the reactor coolant to the steam generators where it is transferred to the light water side to form steam which drives the turbine generators. Many heat exchangers are incorporated in the heat transfer cycle. Their integrity is of prime importance both for the reliability of the power plant and for economic reasons since the loss of heavy water at $300/kg is a substantial penalty. This integrity depends largely on the quality of the heat exchanger tubing and where major heat exchangers are involved, it has been the Ontario Hydro policy to supply tubing to heat exchanger manufacturers on a ''free issue'' basis. This allows better control over the level of inspection perform

Studies on radiation damage to polystyrene exchanger in different cationic forms

International Nuclear Information System (INIS)

Dedgaonkar, V.G.; Jagtap, N.B.; Waghmare, S.; Kulkarni, S.A.

1985-01-01

Polystyrene divinylbenzene copolymer containing nuclear sulfonic acid functional group and H + , Sr 2+ , Cu 2+ , UO 2 2+ or Al 3+ exchangeable cation was subjected to varying gamma doses to study the effects on its physicochemical properties. The exchange capacity and moisture content decreased, the maximum effect was in the case of Cu ++ form of the resin. The data are explained on the basis of metal oxygen bonding. IR spectra indicated the formation of new exchange sites upon irradiation and disapearance of the original functional groups. (author)

U.S.-India safeguards dispute

International Nuclear Information System (INIS)

Sweet, W.

1978-01-01

The current U.S.-India dispute over nuclear safeguards is likely to be the single most important test of the Carter administration's anti-proliferation policies. The Carter administration wants India to accept comprehensive safeguards that would bar further production of nuclear explosives. The Desai government wants to maintain unsafeguarded facilities, in effect keeping the weapons option open. It has been a basic tenet of Indian nuclear policy since the mid-1950s that the big powers must disarm if the small powers are to renounce acquisition of nuclear weapons. As a matter of practical policy, India is willing to forego a nuclear deterrent only if sustained world pressure keeps China's nuclear aspirations in check. As a matter of basic principle, India regards it as unfair and imperialistic that the heavily armed big powers ask for special assurances from the lightly armed small powers. India takes the position that it will cooperate with the United States only voluntarily and only if the nuclear weapon states or at least the superpowers start to clean up their own act. The superpowers must (1) negotiate a comprehensive test ban treaty; (2) accept full-scope safeguards themselves, which would be tantamount to a ban on any further production of weapons-grade materials; and (3) make significant moves toward total nuclear disarmament. The dependence of India on the United States for nuclear supplies is almost negligible. India's major nuclear facilities in operation or under construction include five research reactors, seven power reactors and three reprocessing facilities. Of these 15 facilities, the United States supplied only one (the Tarapur reactor) and 12 of them are not under IAEA safeguards. The United States, in short, is threatening to terminate supplies of low-enriched uranium for just one reactor unless India places these 12 facilities under IAEA safeguards

A proposal for cooperative activities between Japan and Indonesia in the field of nuclear research and nuclear education

International Nuclear Information System (INIS)

Subki, Iyos

2008-01-01

Development and realization of cooperative activities between Japan and Indonesia in nuclear research and education is indeed very important for scientists and engineers of both countries. This bilateral cooperation can easily be expanded into a regional cooperation benefiting the scholars from Asian region which is expecting a New Nuclear Age in the 21st Century. To develop and realize this cooperative activities, in the first step, we invite the ideas of our partners in the Nuclear Institution and in Universities. They are eager to have and undertake this cooperation effort. For nuclear research activities, they have proposed several topics which include: advanced radioactive waste technology and management in a nuclear power plant, innovative fuel development for LWR's, gas cooled reactor for electricity and hydrogen production and a topic on design and construction of high energy accelerator. Institute of Technology - Bandung (ITB), University of Gajah Mada (UGM) and School of Nuclear Technology (STTN/BATAN) are interested in cooperative works which include: joint development of standard curriculum for M.Sc. level in response to increased activities in nuclear research and nuclear power development, exchange of guest lecturers, and exchange of M.Sc. level students. With this cooperation, we want to put very special emphasis on nuclear human resources development (nuclear - HRD) in anticipation of the upcoming nuclear era. (author)

2010/11 Status Report of China Nuclear Data Center

International Nuclear Information System (INIS)

Ge, Zhigang

2011-01-01

China Nuclear Data Center (CNDC) was established in 1975 and joined the nuclear data activities of IAEA as the national nuclear data center of China since 1984. The main task of CNDC: The nuclear data evaluations, libraries and relevant technique researches. The exchange of nuclear data activities with IAEA, foreign nuclear data centers and agencies. The management of domestic nuclear data activities. The services for domestic and foreign nuclear data users.

Nuclear Society of Russia: Ten years in the world nuclear community

International Nuclear Information System (INIS)

Ponomarev-Stepnoi, N.N.; Gagarinski, A.Yu.

2000-01-01

nuclear energy production trends and--most importantly for relations with the mass media and the public--crisis information (latest examples: Tokaimura, the virtual Y2K crisis, etc.), have become important sources of information for the NSR. It should be emphasized that the financial participation of the Russian Minatom (maintained at the insistent request of the NSR) in the NucNet system provides sufficiently wide dissemination of operative nuclear information not only through the NSR headquarters but also via its regional branches and separate enterprises. From its side, NSR has assumed the responsibility for the adequate flow of information on Russian nuclear events to NucNet. As a living and developing organism, the NSR wants to respond to its time's challenges. Several prospective directions could be among the NSR information exchange plans: (1) Independent international analysis of the problems of the use of nuclear energy, which is presently in a stagnation period but with future large-scale development, is as possible today as it never had been before. (2) In the field of public relations, many achievements of Russian and US specialists (in the form of articles, analyzing nuclear energy on the popular and highly professional level) stay inaccessible to others because of the language barrier. A possible joint ANS/NSR project on selection, translation, and exchange of such materials, with their further wide publication, represents an obvious reserve in their societies' information activities. (3) The International Youth Nuclear Congress project (proposed by the Russian nuclear youth and supported by ANS and ENS), conceived as a bridge between generations and a forum for opinion exchange between young nuclear specialists from various countries, deserves further development and appropriation of permanent status in the activities of the world nuclear societies

Radiation stability of anion-exchange resins based on epichlorohydrin and vinylpyridines

International Nuclear Information System (INIS)

Zainutdinov, S.S.; Dzhalilov, A.T.; Askarov, M.A.

1983-01-01

The vigorous development of nuclear technology and atomic energy and the hydrometallurgy of the rare and radioactive metals has made it necessary to create and use ion-exchange materials possessing a high resistance to the action of ionizing radiations and the temperature. In view of this, the necessity has arisen for obtaining ion-exchange materials possessing adequate radiation stability. The results of an investigation of the radiation stability of anion-exchange resins based on the products of spontaneous polymerization in the interaction of epichlorohydrin with vinylpyridines show that they possess higher radiation resistance than the industrial anion-exchange resin AN-31 used at the present time

Proceedings of the nuclear safety seminar, 2011

International Nuclear Information System (INIS)

Amin S Zarkasih; Dhandang P; Rohadi A; Djarwani; Santoso; Abdul Waris; Zaki Su'ud; Sihana; Heryudo Kusumo; Yusri Heni; Yus Rusdian; Judi Pramono; Amil Mardha

2011-06-01

The Proceedings of the nuclear safety seminar by Nuclear Energy Regulatory Agency with the theme of strengthening in nuclear safety control, nuclear security and nuclear safeguard to Introduction of Nuclear Power Plant (NPP) in Indonesia held on Jakarta 27-28 June 2011. The seminar is an annual routine activities which organized by Nuclear Energy Regulatory Agency (BAPETEN) as an exchange for information from scientists and researchers for using nuclear technology. The proceeding consist of 4 articles from keynotes’ speaker and 39 articles from BAPETEN, BATAN and outside participants. (PPIKSN)

Joint thesaurus Part I (A-L) + II (M-Z)[International Nuclear Information System. Energy Technology Data Exchange

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-04-15

This is the second revision of the ETDE/INIS Joint Thesaurus, including all updates up to September 2006. It contains 21 147 valid descriptors and 9 114 forbidden terms. The Joint Thesaurus contains the controlled terminology for indexing all information within the subject scopes of the International Nuclear Information System (INIS) and the Energy Technology Data Exchange (ETDE). The terminology is intended for use in subject descriptions for input or retrieval of information in these systems. The thesaurus is a terminological control device used in translating from the natural language of documents, indexers or users into a more constrained system language It is also a controlled and dynamic vocabulary of semantically and generically related terms which covers a specific domain of knowledge. The basic terminology in this thesaurus goes back to the 1969 edition of the EURATOM Thesaurus. The structure subsequently given to that terminology was the result of a systematic study performed by INIS subject specialists. Further expansion of the thesaurus terminology was done by ETDE to incorporate information on all forms of energy. The ETDE/INIS Joint Thesaurus is the result of continued editing, carried out in parallel to the processing of the INIS and ETDE databases. The domain of knowledge covered by the Joint Thesaurus includes physics (in particular, plasma physics, atomic and molecular physics, and especially nuclear and high-energy physics), chemistry, materials science, earth sciences, radiation biology, radioisotope effects and kinetics, applied life sciences, radiology and nuclear medicine, isotope and radiation source technology, radiation protection, radiation applications, engineering, instrumentation, fossil fuels, synthetic fuels, renewable energy sources, advanced energy systems, fission and fusion reactor technology, safeguards and inspection, waste management, environmental aspects of the production and consumption of energy from nuclear and non-nuclear

International co-operation through scientific and technical nuclear societies

International Nuclear Information System (INIS)

Manning Muntzing, L.

1983-01-01

As an international organization the American Nuclear Society (ANS) has played an active role in international co-operation of nuclear technology exchange since its establishment in 1954. The ANS has a membership of over 13,000 individuals, of whom approximately 1200 live overseas in forty countries. To carry out the goals of the Society, local sections have been established. Currently the ANS maintains 48 local sections in the United States of America and 8 overseas local sections in Africa, Asia, Europe and South America. The ANS also has formal agreements for co-operation with The Asociacion Argentina de Tecnologia Nuclear (AATN), the Israel Nuclear Society (INS), and the Chinese Nuclear Society (CNS). In 1977 the Japan Atomic Energy Society (JAES), the European Nuclear Society (ENS), and the ANS co-operation in sponsoring the First International Conference on Transfer of Nuclear Technology (ICONTT I) in Tehran, Iran. In 1982, the Second International Conference on Transfer of Nuclear Technology (ICONTT II), Buenos Aires, Argentina, was sponsored through the co-operation of the AATN, the ENS and the ANS. The ANS and its overseas sections sponsor the Pacific Basin Conference approximately every three years to discuss nuclear matters of concern to the countries around the Pacific Ocean. In 1981 the ANS held a Nuclear Technology Exhibit in Beijing, the People's Republic of China. In addition to meetings, the ANS is extensively involved in the co-operative exchange of applied nuclear research information through its publications. Nuclear Technology, a technical journal, is published monthly under joint ownership of the ENS and the ANS. The ANS has been a leader in voluntary standards development since 1958. In its dedication to the co-operation of international nuclear technology the ANS maintains a comprehensive international exchange of nuclear standards

Sleeving repair of heat exchanger tubes

International Nuclear Information System (INIS)

Street, Michael D.; Schafer, Bruce W.

2000-01-01

Defective heat exchanger tubes can be repaired using techniques that do not involve the cost and schedule penalties of component replacement. FTI's years of experience repairing steam generator tubes have been successfully applied to heat exchangers. Framatome Technologies heat exchanger sleeves can bridge defective areas of the heat exchanger tubes, sleeves have been designed to repair typical heat exchanger tube defects caused by excessive tube vibration, stress corrosion cracking, pitting or erosion. By installing a sleeve, the majority of the tube's heat transfer and flow capacity is maintained and the need to replace the heat exchanger can be delayed or eliminated. Both performance and reliability are improved. FTI typically installs heat exchanger tube sleeves using either a roll expansion or hydraulic expansion process. While roll expansion of a sleeve can be accomplished very quickly, hydraulic expansion allows sleeves to be installed deep within a tube where a roll expander cannot reach. Benefits of FTI's heat exchanger tube sleeving techniques include: - Sleeves can be positioned any where along the tube length, and for precise positioning of the sleeve eddy current techniques can be employed. - Varying sleeve lengths can be used. - Both the roll and hydraulic expansion processes are rapid and both produce joints that do not require stress relief. - Because of low leak rates and speed of installations, sleeves can be used to preventatively repair likely-to-fail tubes. - Sleeves can be used for tube stiffening and to limit leakage through tube defects. - Because of installation speed, there is minimal impact on outage schedules and budgets. FTI's recently installed heat exchanger sleeving at the Kori-3 Nuclear Power Station in conjunction with Korea Plant Service and Engineering Co., Ltd. The sleeves were installed in the 3A and 3B component cooling water heat exchangers. A total of 859 tubesheet and 68 freespan sleeves were installed in the 3A heat

Nuclear Physics Laboratory technical progress report

International Nuclear Information System (INIS)

1991-01-01

This contract supports broadly based experimental work in intermediate energy nuclear physics. The program includes pion- nucleon studies at TRIUMF and LAMPF, inelastic pion scattering and charge exchange reactions at LAMPF, and nucleon charge exchange at LAMPF/NTOF. The first results of spin-transfer observables in the isovector (rvec p,rvec n) reaction are included in this report. Our data confirm the tentative result from (rvec p,rvec p) reactions that the nuclear isovector spin response shows neither longitudinal enhancement nor transverse quenching. Our program in quasifree scattering of high energy pions shows solid evidence of isoscalar enhancement of the nuclear nonspin response. We include several comparisons of the quasifree scattering of different probes. Results from our efforts in the design of accelerator RF cavities are also included in this report

Peaceful uses of nuclear weapon plutonium; Friedliche Verwertung von Plutonium aus Kernwaffen

Energy Technology Data Exchange (ETDEWEB)

Burtak, F. [Siemens AG Bereich Energieerzeugung (KWU), Erlangen (Germany)

1996-06-01

In 1993, the U.S.A. and the CIS signed Start 2 (the Strategic Arms Reduction Treaty) in which they committed themselves the reduce their nuclear weapon arsenals to a fraction of that of 1991. For forty-five years the antagonism between the superpowers had been a dominating factor in world history, determining large areas of social life. When Start 2 will have been completed in 2003, some 200 t of weapon grade plutonium and some 2000 t of highly enriched uranium (Heu) will arise from dismantling nuclear weapons. In the absence of the ideological ballast of the debate about Communism versus Capitalism of the past few decades there is a chance of the grave worldwide problem of safe disposal and utilization of this former nuclear weapon material being solved. Under the heading of `swords turned into plowshares`, plutonium and uranium could be used for peaceful electricity generation. (orig.) [Deutsch] 1993 unterzeichneten die USA und GUS das Start-2-Abkommen (Strategic Arms Reduction Treaty), in dem sie sich zur Verringerung der Anzahl ihrer Nuklearwaffen auf einen Bruchteil des Bestandes von 1991 verpflichten. 45 Jahre lang stellte die Auseinandersetzung der Supermaechte einen dominierenden Faktor der Weltpolitik dar und bestimmte weite Teile des gesellschaftlichen Lebens. Mit der geplanten Erfuellung von Start 2 im Jahr 2003 werden ca. 200 t waffengraediges Plutonium und ca. 2000 t highly enriched uranium (Heu) aus der Demontage der Kernwaffen anfallen. Ohne den ideologischen Ballast der vergangenen jahrezehntelangen Auseinandersetzung zwischen `Kommunismus` und `Kapitalismus` besteht die Chance, das gravierende weltweite Problem der sicheren Entsorgung und Verwertung dieses ehemaligen Kernwaffenmaterials zu loesen. Unter dem Motto `Schwerter zu Pflugscharen` koennte das Plutonium und Uran zur friedlichen Elektrizitaetserzeugung genutzt werden. (orig.)

Modeling ion exchange in clinoptilolite using the EQ3/6 geochemical modeling code

International Nuclear Information System (INIS)

Viani, B.E.; Bruton, C.J.

1992-06-01

Assessing the suitability of Yucca Mtn., NV as a potential repository for high-level nuclear waste requires the means to simulate ion-exchange behavior of zeolites. Vanselow and Gapon convention cation-exchange models have been added to geochemical modeling codes EQ3NR/EQ6, allowing exchange to be modeled for up to three exchangers or a single exchanger with three independent sites. Solid-solution models that are numerically equivalent to the ion-exchange models were derived and also implemented in the code. The Gapon model is inconsistent with experimental adsorption isotherms of trace components in clinoptilolite. A one-site Vanselow model can describe adsorption of Cs or Sr on clinoptilolite, but a two-site Vanselow exchange model is necessary to describe K contents of natural clinoptilolites

Project development: testing of heat exchange of cooling system and cleaning fuel pool of NPP Cofrentes; Desarrollo del proyecto Prueba de Intercambio Termico del Sistema de Enfriamiento y Limpieza de la Piscina de combustible (G41) de Central Nuclear de Cofrentes

Energy Technology Data Exchange (ETDEWEB)

Lopez, B.; Vaquer, J. I.; Mota, M.; Reyes, S.; Palomo, M.; Ruiz, G.; Rebollo, C.

2012-07-01

Heat exchanger tests were carried out and data in the thermodynamic models developed, turned and can verify that the efficiency of heat exchange met the requirements. The work concluded complying at all times with the technical specifications and quality proposals by the Department of engineering at the Central Nuclear de Cofrentes.

Methods of thermal power extraction from nuclear sources for meeting the consumer system demands

International Nuclear Information System (INIS)

Sellej, J.

1985-01-01

The technical design is discussed of heat extraction from nuclear power plants and heating plants. Variant technical designs are discussed of hot water and steam supply, including the basic aspects of nuclear safety. Hot water supplies are technically provided by heat exchanger units connected to turbines, or by heating turbines. The advantages and disadvantages of the two designs are discussed. The possibility of heat extraction by steam from the nuclear power plant is provided by steam exchangers, i.e., steam exchanger cascades, the so-called inserted steam circuit. Supplies of steam from nuclear sources, as against supplies of hot water have not yet been technically resolved with regard to safety, design and economic benefit. Nuclear heating plants have also been designed for hot water supply, but not yet for steam supply. (Pu)

Nuclear power plants

International Nuclear Information System (INIS)

Kiyokawa, Teruyuki; Soman, Yoshindo.

1985-01-01

Purpose: To constitute a heat exchanger as one unit by integrating primary and secondary coolant circuits with secondary coolant circuit and steam circuit into a single primary circuit and steam circuit. Constitution: A nuclear power plant comprises a nuclear reactor vessel, primary coolant pipeways and a leakage detection system, in which a dual-pipe type heat exchanger is connected to the primary circuit pipeway. The heat conduction tube of the heat exchanger has a dual pipe structure, in which the inside of the inner tube is connected to the primary circuit pipeway, the outside of the outer tube is connected to steam circuit pipeway and a fluid channel is disposed between the inner and outer tubes and the fluid channel is connected to the inside of an expansion tank for intermediate heat medium. The leak detection system is disposed to the intermediate heat medium expansion tank. Sodium as the intermediate heat medium is introduced from the intermediate portion (between the inner and outer tubes) by way of inermediate heat medium pipeways to the intermediate heat medium expansion tank and, further, to the intermediate portion for recycling. (Kawakami, Y.)

Potential cooperative measures on nuclear issues in Asia

International Nuclear Information System (INIS)

Olsen, J.

1997-01-01

Cooperation on nuclear issues is receiving increased attention in Asia. In Northeast Asia, where the nuclear industry is well-developed, cooperation in the back end of the nuclear fuel cycle could help deal with issues such as disposition of spent fuel and long term storage options. In Southeast Asia, where countries are just beginning to introduce nuclear energy, cooperation would be useful in developing standards for the nuclear industry. Throughout Asia, nuclear research and power activities can raise concerns about safety, environmental pollution and proliferation. The sharing of relevant information, i.e. cooperative monitoring, will be essential to addressing these issues. In fact, a number of regional interactions on nuclear issues are already occurring. These range from training exchanges sponsored by the more advanced states to participation in environmental monitoring of the East Sea (Sea of Japan). Several states are considering sharing information from their nuclear facilities; some exchanges of radiation data are already in place. The KEDO reactor project will involve close working relations between the nuclear experts of South Korea, North Korea, Japan, and the US. Areas for further regional cooperation are discussed

Exchangeability of RI image data and its effect

Energy Technology Data Exchange (ETDEWEB)

Kojima, K; Hiraki, T [Kanazawa Univ. (Japan). School of Paramedicine; Nakajima, K; Hisada, K; Yamada, M

1981-10-01

Of RI image data processing machines, the exchangeability of data between the VIP-450 system (Ohio-Nuclear Inc.) and the DAP-5000N system (Toshiba Co.) was examined. The exchangeability requires uniformity of arrangement of bits and the data sequence between the machines. Otherwise, the form of memory of either machine should be changed. The exchangeability of data between the machines would have the following advantages: characteristic programs of each machine can be used for the same data, producing more valuable information. Data collection can be performed by any machine, increasing the efficiency of examination. It is not necessary to provide all machines with special attachments. It permits data input into large machines or minicomputers in the development of programs.

Exchangeability of RI image data and its effect

International Nuclear Information System (INIS)

Kojima, Kazuhiko; Hiraki, Tatsunosuke; Nakajima, Kenichi; Hisada, Kinichi; Yamada, Masato.

1981-01-01

Of RI image data processing machines, the exchangeability of data between the VIP-450 system (Ohio-Nuclear Inc.) and the DAP-5000N system (Toshiba Co.) was examined. The exchangeability requires uniformity of arrangement of bits and the data sequence between the machines. Otherwise, the form of memory of either machine should be changed. The exchangeability of data between the machines would have the following advantages: characteristic programs of each machine can be used for the same data, producing more valuable information. Data collection can be performed by any machine, increasing the efficiency of examination. It is not necessary to provide all machines with special attachments. It permits data input into large machines or minicomputers in the development of programs. (Chiba, N.)

Nuclear war hazards

International Nuclear Information System (INIS)

Chazov, E.I.; Il'in, L.A.; Gus'kova, A.K.

1982-01-01

An attempt is made to forecast medical and bilogical and aftereffects of nuclear weapons application in a number of situations. In particular, the effects of a single high-yield air or surface nuclear explosion on a city with 1 mln population are considered as well as the aftereffects of the exposure of human beings to local radioactive fallouts outside the ground zero of a surface nuclear explosion. The aftereffects for the population of local and global radioactive fallouts caused by the realization of one of the adopted in the West variants of mass nuclear strives exchange between the hostile sides are estimated. Certain aspects of medical and biological aftereffects of neutron weapons application are discussed

Treating Coulomb exchange contributions in relativistic mean field calculations: why and how

International Nuclear Information System (INIS)

Giai, Nguyen Van; Liang, Haozhao; Gu, Huai-Qiang; Long, Wenhui; Meng, Jie

2014-01-01

The energy density functional (EDF) method is very widely used in nuclear physics, and among the various existing functionals those based on the relativistic Hartree (RH) approximation are very popular because the exchange contributions (Fock terms) are numerically rather onerous to calculate. Although it is possible to somehow ‘mock up’ the effects of meson-induced exchange terms by adjusting the meson–nucleon couplings, the lack of Coulomb exchange contributions hampers the accuracy of predictions. In this work, we show that the Coulomb exchange effects can be easily included with good accuracy in a perturbative approach. Therefore, it would be desirable for future relativistic EDF models to incorporate Coulomb exchange effects, at least to some order of perturbation

Global nuclear safety culture

International Nuclear Information System (INIS)

1997-01-01

As stated in the Nuclear Safety Review 1996, three components characterize the global nuclear safety culture infrastructure: (i) legally binding international agreements; (ii) non-binding common safety standards; and (iii) the application of safety standards. The IAEA has continued to foster the global nuclear safety culture by supporting intergovernmental collaborative efforts; it has facilitated extensive information exchange, promoted the drafting of international legal agreements and the development of common safety standards, and provided for the application of safety standards by organizing a wide variety of expert services

Studies on indigenous ion exchange resins: alkali metal ions-hydrogen ion exchange equilibria

International Nuclear Information System (INIS)

Shankar, S.; Kumar, Surender; Venkataramani, B.

2001-01-01

With a view to select a suitable ion exchange resin for the removal of radionuclides (such as cesium, strontium etc.) from low level radioactive effluents, alkali metal ion -H' exchanges on nine indigenous gel- and macroporous-type and nuclear grade resins have been studied at a total ionic strength of 0.1 mol dm .3 (in the case ofCs' -H' exchange it was 0.05 mol dm .3 ). The expected theoretical capacities were not attained by all the resins for the alkali metal ions. The water content (moles/equiv.) of the fully swollen resins for different alkali metal ionic forms do not follow the usual sequence of greater the tendency of the cation to hydrate the higher the water uptake, but a reverse trend. The ion exchange isotherms (plots of equivalent fractions of the ion in resin phase, N M1 to that in solution, N M ) were not satisfactory and sorption of cations, for most of the resins, was possible only when the acidity of the solution was lowered. The variations of the selectivity coefficient, K, with N M show that the resins are highly cross linked and the selectivity sequence: Cs + >K + >Na + >Li + , obtained for all the resins indicate that hydrated ions were involved in the exchange process. However, the increase in the selectivity was not accompanied by the release of water, but unusual uptake of water, during the exchange process. The characteristics of macroporous resins were not significantly different from those of the gel-type resins. The results are discussed in terms of heterogeneity in the polymer net work, improper sulphonation process resulting in the formation of functional groups at inaccessible sites with weak acidic character and the overall lack of control in the preparation of different resins. (author)

Commercial Ion Exchange Resin Vitrification Studies

International Nuclear Information System (INIS)

Cicero-Herman, C.A

2002-01-01

In the nuclear industry, ion exchange resins are used for purification of aqueous streams. The major contaminants of the resins are usually the radioactive materials that are removed from the aqueous streams. The use of the ion exchange resins creates a waste stream that can be very high in both organic and radioactive constituents. Therefore, disposal of the spent resin often becomes an economic problem because of the large volumes of resin produced and the relatively few technologies that are capable of economically stabilizing this waste. Vitrification of this waste stream presents a reasonable disposal alternative because of its inherent destruction capabilities, the volume reductions obtainable, and the durable product that it produces

Agreement between the Dominican Republic and the Agency for the Application of Safeguards in Connection with the Treaty for the Prohibition of Nuclear Weapons in Latin America and the Treaty on the Non-Proliferation of Nuclear Weapons. An agreement by Exchange of Letters with the Dominican Republic to amend the Protocol to the Safeguards Agreement

International Nuclear Information System (INIS)

2007-01-01

Agreement between the Dominican Republic and the Agency for the Application of Safeguards in Connection with the Treaty for the Prohibition of Nuclear Weapons in Latin America and the Treaty on the Non-Proliferation of Nuclear Weapons. An agreement by Exchange of Letters with the Dominican Republic to amend the Protocol to the Safeguards Agreement

Organic resin anion exchangers for the treatment of radioactive wastes

International Nuclear Information System (INIS)

Dyer, A.; McGinnes, D.F.

1988-07-01

Organic anion exchange resins are evaluated for 99-TcO 4 - (pertechnate) removed from aqueous nuclear waste streams. Chemical, thermal and radiation stabilities were studied. Selected resins were examined in detail for their selectivities in the presence of I - , NO 3 - , SO 4 = , CO 3 = , Cl - and OH - . Ion exchange equilibria and kinetic mechanisms were determined. Preliminary investigations of cement encapsulation in polymer modified form were made and some leach studies carried out. (author)

Development of low temperature solid state joining technology of dissimilar for nuclear heat exchanger tube components

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-08-15

By conventional fusion welding process (TIG), a realization of reliable and sound joints for the nuclear heat exchanger components is very difficult, especially for the parts comprising of the dissimilar metal couples (Ti-STS, Ti-Cu alloy etc.). This is mainly attributed to the formation of brittle intermetallics (Ti{sub x}Cu{sub y}, Ti{sub x}Fe{sub y}, Ti{sub x}Ni{sub y} etc.) and wide difference in physical properties. Moreover, it usually employs very high thermal input, so making it difficult to obtain sound joints due to generations of high residual stresses and degradation of the adjacent base metals, even for similar metal combinations. In this project, the low temperature solid-state joining technology was established by developing new alloy fillers, e.g. the multi-component eutectic based alloys or amorphous alloys, and thereby lowering the joining temperature down to {approx}800 .deg. C without affecting the structural properties of base metals. Based on a low temperature joining, the interlayer engineering technology was then developed to be able to eliminate the brittleness of the joints for strong Ti-STS dissimilar joints, and the diffusion brazing technology of Ti-Ti with a superior joining strength and corrosion-resistance comparable to those of base metal were developed. By using those developed technologies, the joining procedures feasible for the heat exchanger components were finally established for the dissimilar metal joints including Ti tube sheet to super STS tube, Ti tube sheet to super STS tube sheet, and the joints of the Ti tube to Ti tube sheet

Proceedings of the 8. National Seminar on Technology and Safety of Nuclear Power Plants and Nuclear Facilities

International Nuclear Information System (INIS)

Antariksawan, Anhar R.; Soetrisnanto, Arnold Y.; Aziz, Ferhat; Untoro, Pudji; Su'ud, Zaki; Zarkasi, Amin Santosa; Umar, Faraz H.; Teguh Bambang; Hafnan, M.; Mustafa, Bustani; Rosfian, H.

2002-10-01

The eight proceeding of National Seminar on Technology and Safety of Nuclear Power Plant and Nuclear Facilities held by National Atomic Energy Agency and University of Trisakti. The aims of Seminar is to exchange and disseminate information about safety and nuclear Power Plant Temperature Reactor and Application for National Development sustain able and High Technology. This Seminar covers all aspect Technology, Power Reactor : Research Reactor; High Temperature Reactor and Nuclear Facilities. There are 33 articles have separated index

A method for embedding granulated or spent ion-exchanging organic substances in concrete

International Nuclear Information System (INIS)

Christensen, H.; Jejes, P.

1976-01-01

A method of embedding in concrete a spent ion-exchanging organic substance originating from a scrubbing-circuit of a nuclear reactor Prior to solidification of the mixture, a substance is incorporated therewith said substance being capable of preventing water in the grains of the ion-exchanging substance from penetrating into the solidified product

Charge exchange in collisions of beryllium with its ion.

Science.gov (United States)

Zhang, Peng; Dalgarno, Alexander; Côté, Robin; Bodo, Enrico

2011-11-14

Close-coupling calculations of the resonance and near resonance charge exchange in ion-atom collisions of Be at low and intermediate energies are presented. Accurate ab initio calculations are carried out of the Born-Oppenheimer potentials and the non-adiabatic couplings that are due to the finite nuclear masses and drive the near resonance charge exchange. We show that the near resonance charge exchange cross section follows Wigner's threshold law of inelastic processes for energies below 10(-8) eV and that the zero temperature rate constant for it is 4.5 × 10(-10) cm(3) s(-1). At collision energies much larger than the isotope shift of the ionization potentials of the atoms, we show that the near resonance charge exchange process is equivalent to the resonance charge exchange with cross sections having a logarithmic dependence. We also investigate the perturbation to the charge exchange process due to the non-adiabatic interaction to an electronic excited state. We show that the influence is negligible at low temperatures and still small at intermediate energies despite the presence of resonances.

Exchange of pressurizer safeguarding system at Biblis nuclear power station

International Nuclear Information System (INIS)

Weber, D.; Hofbeck, W.

1991-01-01

Valves and piping of the pressurizer safeguarding system are exchanged and reset in such a way that they are suitable not only for discharging steam, but also for discharging a water-steam mixture and hot pressurized water; for the emergency measure of primary depressurization by hand (bleed) in the event of failure of the entire feedwater supply and station black-out, and in the event of operational transients with supposed failure of the reactor scram (ATWS). To achieve this, in addition to the requirements of the pressurizer discharging station, changes have to be made to the valve drive to dominate the water loads. During the 1990 inspection this exchange of the pressurizer discharging station was performed at the Biblis A unit as the first German plant. (orig.) [de

Haiyang nuclear power construction management and practice

International Nuclear Information System (INIS)

Wang Fengxue

2010-01-01

The paper introduces the basic situation of Shandong Haiyang Nuclear Power Plant, as well as the management and progress of the project. Through the construction management practice, problems encountered in nuclear power construction are put forward for peer exchange and discussion. (author)

Helically coiled tube heat exchanger

International Nuclear Information System (INIS)

Harris, A.M.

1981-01-01

In a heat exchanger such as a steam generator for a nuclear reactor, two or more bundles of helically coiled tubes are arranged in series with the tubes in each bundle integrally continuing through the tube bundles arranged in series therewith. Pitch values for the tubing in any pair of tube bundles, taken transverse to the path of the reactor coolant flow about the tubes, are selected as a ratio of two unequal integers to permit efficient operation of each tube bundle while maintaining the various tube bundles of the heat exchanger within a compact envelope. Preferably, the helix angle and tube pitch parallel to the path of coolant flow are constant for all tubes in a single bundle so that the tubes are of approximately the same length within each bundle

Approaches to 'eternal' accompaniment regalement of nuclear energy installation decommissioning

International Nuclear Information System (INIS)

Dryapachenko, Ihor; Trofimova, Nina

2003-01-01

The stunning rate of events after striking the push button AZ5 in April 26, 1986 while that only rises. Boundless even for the super-power world states the complex of scientific, technological, organizational, economical and social problems became in 1991 unique property of Ukraine. It has added to the operational power reactors (now 13) at practical absence of an infrastructure of a closed fuel cycle. At the same time Ukrainian economics always' will depend on nuclear power engineering. In it are very much positive aspect concerning high technological and scientifically based contents and future non-alternative of the nuclear power industry on a global scale. The errors in an estimation of separate links of such composite model are not killed mutually, but only add. Uncertainty in estimations of natural or public processes will cause to large uncertainty of general forecast. A laborious transaction of the rules production or the legitimated algorithms of the activity realization reach the foreseen controllability. On our view the following logical thesis of such concept should be comprehension that the rules of decommissioning of a nuclear-power plant should provide the controllability with matched activities not one generation of performers. The impressive achievements of scientific-technological revolution of last decades are accompanied 'non-regalement' from the point of view of life on a planet by disastrous effects. The nuclear technologies overtake in this sense with that feature, that the 'half-life' periods of these consequences often much more large than the whole written history of mankind. The most distant consequences of the long-term processing with radioactive materials bound on our view with the human factor. If for 30-100 years beforehand it is possible to count destiny of radiological contamination or green meadows but to provide behavior of the people or society, as a whole is high-gravity even per annum forward. Objectivity of laws of history

The value of peer reviews to nuclear plant safety

International Nuclear Information System (INIS)

Subalusky, W.T. Jr.

1994-01-01

On a global basis, the nuclear utility industry has clearly demonstrated the value of peer reviews for improving nuclear safety and overall plant performance. Peer reviews are conducted by small teams of technical experts who review various aspects of plant operation, recognize strengths and recommend improvements, thereby stimulating a positive response to the recommendations. U.S. nuclear utilities initiated the operator-to-operator peer review process first through the Institute of Nuclear Power Operations (INPO). Now, voluntary peer reviews are an important activity of the World Association of Nuclear Operators (WANO). Formed just five years ago. WANO has made significant progress in its key activities of the operator-to-operator exchanges, operating experience exchange, monitoring of plant performance indicators and sharing of good practices worldwide. A fifth activity, peer review on a strictly voluntary basis, is pertinent to this paper

Development process and achievements of China nuclear agricultural sciences

International Nuclear Information System (INIS)

Wen Xianfang

2009-01-01

This paper outlines the creation of our nuclear agricultural sciences and the development process as well as the main results for agricultural applications of nuclear technology. Nuclear agricultural sciences in China began in 1956, after 50 years of development, the collaborative research network, the academic exchange network, and the international exchange network have been formatted. These three networks comprehensively have promoted the formation and development of China nuclear agricultural sciences. Remarkable results have been achieved in the fields of radiation mutation breeding, space mutation breeding, isotope tracer technique application in agriculture, agricultural products storage and preservation of irradiation processing, irradiation sterile insect technique, low-doses of radiation to stimulate output. In addition, the concept of suggestions on the future development of China nuclear agricultural sciences, as well as the priorities of research fields are put forward. (authors)

Radiation effects on ion exchange materials

Energy Technology Data Exchange (ETDEWEB)

Gangwer, T.E.; Goldstein, M.; Pillay, K.K.S.

1977-11-01

An extensive literature review and data compilation has been completed on the radiation-damage of ion exchange resins. The primary goal of the study has been to review the available literature on ion exchange materials used in, as well as those with potential for use in, the nuclear fuel and waste reprocessing areas. The physical and chemical properties of ion exchangers are reviewed. Experimental parameters useful in characterizing the effects of radiation on synthetic ion exchange resins are identified or defined. In compiling the diverse types of data, an effort was made to present the experimental data or experimentally based parameters in a format that would be useful for inter-comparing radiation effects on resins. When subject to radiation there are various general trends or qualitative effects displayed by the different types of resins. These radiation-trends and effects have been formulated into qualitative statements. The present day level of understanding of the behavior of resins under ionizing radiation is too limited to justify quantitative predictive modeling. The limitations and deficiencies of the literature are discussed and the experimentation needed to achieve quantitative modeling are outlined. 14 figs., 108 references.

Radiation effects on ion exchange materials

International Nuclear Information System (INIS)

Gangwer, T.E.; Goldstein, M.; Pillay, K.K.S.

1977-11-01

An extensive literature review and data compilation has been completed on the radiation-damage of ion exchange resins. The primary goal of the study has been to review the available literature on ion exchange materials used in, as well as those with potential for use in, the nuclear fuel and waste reprocessing areas. The physical and chemical properties of ion exchangers are reviewed. Experimental parameters useful in characterizing the effects of radiation on synthetic ion exchange resins are identified or defined. In compiling the diverse types of data, an effort was made to present the experimental data or experimentally based parameters in a format that would be useful for inter-comparing radiation effects on resins. When subject to radiation there are various general trends or qualitative effects displayed by the different types of resins. These radiation-trends and effects have been formulated into qualitative statements. The present day level of understanding of the behavior of resins under ionizing radiation is too limited to justify quantitative predictive modeling. The limitations and deficiencies of the literature are discussed and the experimentation needed to achieve quantitative modeling are outlined. 14 figs., 108 references

Quasiparticle method in relativistic mean-field theories of nuclear structure

International Nuclear Information System (INIS)

Ai, H.

1988-01-01

In recent years, in order to understand the success of Dirac phenomenology, relativistic Brueckner-Hartree-Fock (RBHF) theory has been developed. This theory is a relativistic many-body theory of nuclear structure. Based upon the RBHF theory, which is characterized as having no free parameters other than those introduced in fitting free-space nucleon-nucleon scattering data, we construct an effective interaction. This interaction, when treated in a relativistic Hartree-Fock approximation, reproduces, rather accurately, the nucleon self-energy in nuclear matter, Migdal parameters obtained via relativistic Brueckner-Hartree-Fock calculations, and the saturation curves calculated with the full relativistic Brueckner-Hartree-Fock theory. This effective interaction is constructed by adding a number of pseudoparticles to the mesons used to construct one-boson-exchange (OBE) models of the nuclear force. The pseudoparticles have relatively large masses and either real or imaginary coupling constants. (For example, exchange of a pseudo-sigma with an imaginary coupling constant has the effect of reducing the scalar attraction arising from sigma exchange, while exchange of a pseudo-omega with an imaginary coupling constant has the effect of reducing the repulsion arising from omega exchange. The terms beyond the Born term in the case of pion exchange are well simulated by pseudo-sigma exchange with a real coupling constant.) The effective interaction constructed here may be used for calculations of the properties of finite nuclei in a relativistic Hartree-Fock approximation

Alfa-Laval plate heat exchangers for the power industries

International Nuclear Information System (INIS)

Kitae, Junnosuke; Mtsuura, Kazuyuki

1979-01-01

Within power-generating plants, the transfer and conversion of heat energy of very large quantity are carried out in the process of energy conversion, accordingly the importance of heat exchangers is very high. Heretofore, multi-tube heat exchangers have been used mostly, but Alfa-Laval group developed the heat exchanger with very high efficiency to incorporate it effectively into a power-generating plant. In this plate type heat exchanger, the heat transfer efficiency is very high, and the quantity of stagnation is small as it is compact, consequently it is suitable to the secondary cooling for power-generating plant or the heat exchange of high-priced liquid heat media such as heavy water. Originally, plate type heat exchangers were used for food and chemical industries, therefore the prevention of mixing two liquids, sanitary construction, and corrosion resistance were required. Then they were adopted in iron and steel industry, and large thermal load, large heat transfer area and corrosion resistance to sea water were required. They were adopted in a nuclear power plant for the first time in 1964. In this heat exchanger, channels are formed with corrugated metal sheets, and titanium, stainless steels, Incoloy, Hastelloy and others are used as occasion demands. The Alfa-Laval heat exchangers and their features are explained. (Kako, I.)

Device for removing alkali metal residues from heat exchanger

International Nuclear Information System (INIS)

Matal, O.

1987-01-01

The main parts of the facility consists of a condensing vessel and a vacuum pump unit interconnected via a vacuum pipe. The heat exchanger is heated to a temperature at which the alkali metal residues evaporate. Metal vapors are collected in the condensing vessel where they condense. The removal of the alkali metal residues from the heat exchanger pipes allows thorough inspection of the pipe inside during scheduled nuclear power plant shutdowns. The facility can be used especially with reverse steam generators. (E.S.). 1 fig

Nuclear Symbiosis - A Means to Achieve Sustainable Nuclear Growth while Limiting the Spread of Sensititive Nuclear Technology

Energy Technology Data Exchange (ETDEWEB)

David Shropshire

2009-09-01

Global growth of nuclear energy in the 21st century is creating new challenges to limit the spread of nuclear technology without hindering adoption in countries now considering nuclear power. Independent nuclear states desire autonomy over energy choices and seek energy independence. However, this independence comes with high costs for development of new indigenous fuel cycle capabilities. Nuclear supplier states and expert groups have proposed fuel supply assurance mechanisms such as fuel take-back services, international enrichment services and fuel banks in exchange for recipient state concessions on the development of sensitive technologies. Nuclear states are slow to accept any concessions to their rights under the Non-Proliferation Treaty. To date, decisions not to develop indigenous fuel cycle capabilities have been driven primarily by economics. However, additional incentives may be required to offset a nuclear state’s perceived loss of energy independence. This paper proposes alternative economic development incentives that could help countries decide to forgo development of sensitive nuclear technologies. The incentives are created through a nuclear-centered industrial complex with “symbiotic” links to indigenous economic opportunities. This paper also describes a practical tool called the “Nuclear Materials Exchange” for identifying these opportunities.

Nuclear Anapole Moments

Energy Technology Data Exchange (ETDEWEB)

Michael Ramsey-Musolf; Wick Haxton; Ching-Pang Liu

2002-03-29

Nuclear anapole moments are parity-odd, time-reversal-even E1 moments of the electromagnetic current operator. Although the existence of this moment was recognized theoretically soon after the discovery of parity nonconservation (PNC), its experimental isolation was achieved only recently, when a new level of precision was reached in a measurement of the hyperfine dependence of atomic PNC in 133Cs. An important anapole moment bound in 205Tl also exists. In this paper, we present the details of the first calculation of these anapole moments in the framework commonly used in other studies of hadronic PNC, a meson exchange potential that includes long-range pion exchange and enough degrees of freedom to describe the five independent S-P amplitudes induced by short-range interactions. The resulting contributions of pi-, rho-, and omega-exchange to the single-nucleon anapole moment, to parity admixtures in the nuclear ground state, and to PNC exchange currents are evaluated, using configuration-mixed shell-model wave functions. The experimental anapole moment constraints on the PNC meson-nucleon coupling constants are derived and compared with those from other tests of the hadronic weak interaction. While the bounds obtained from the anapole moment results are consistent with the broad ''reasonable ranges'' defined by theory, they are not in good agreement with the constraints from the other experiments. We explore possible explanations for the discrepancy and comment on the potential importance of new experiments.

Nuclear Anapole Moments

International Nuclear Information System (INIS)

Michael Ramsey-Musolf; Wick Haxton; Ching-Pang Liu

2002-01-01

Nuclear anapole moments are parity-odd, time-reversal-even E1 moments of the electromagnetic current operator. Although the existence of this moment was recognized theoretically soon after the discovery of parity nonconservation (PNC), its experimental isolation was achieved only recently, when a new level of precision was reached in a measurement of the hyperfine dependence of atomic PNC in 133Cs. An important anapole moment bound in 205Tl also exists. In this paper, we present the details of the first calculation of these anapole moments in the framework commonly used in other studies of hadronic PNC, a meson exchange potential that includes long-range pion exchange and enough degrees of freedom to describe the five independent S-P amplitudes induced by short-range interactions. The resulting contributions of pi-, rho-, and omega-exchange to the single-nucleon anapole moment, to parity admixtures in the nuclear ground state, and to PNC exchange currents are evaluated, using configuration-mixed shell-model wave functions. The experimental anapole moment constraints on the PNC meson-nucleon coupling constants are derived and compared with those from other tests of the hadronic weak interaction. While the bounds obtained from the anapole moment results are consistent with the broad ''reasonable ranges'' defined by theory, they are not in good agreement with the constraints from the other experiments. We explore possible explanations for the discrepancy and comment on the potential importance of new experiments

Operating experience with nuclear power plants 2013; Betriebserfahrungen mit Kernkraftwerken 2013

Energy Technology Data Exchange (ETDEWEB)

Anon.

2014-07-01

The VGB Technical Committee 'Nuclear Plant Operation' has been exchanging operating experience about nuclear power plants for more than 30 years. Plant operators from several European countries are participating in the exchange. A report is given on the operating results achieved in 2013, events important to plant safety, special and relevant repair, and retrofit measures from Belgium, Germany, Finland, the Netherlands, Switzerland, and Spain. (orig.)

Atucha I nuclear power plant: repair works in QK02W01 moderator system heat exchanger; Central nuclar Atucha I. Intervencion al intercambiador nro2 del moderador

Energy Technology Data Exchange (ETDEWEB)

Olivieri, Luis E; Zanni, Pablo A [Nucleoelectrica Argentina SA (NASA), Lima (Argentina). Central Nuclear Atucha 1

2000-07-01

Atucha I nuclear power plant moderator system operates with highly radioactive heavy water, a pressure of 115 Bar and temperatures of about 200 C degrees. In March 2000, an increasing leakage of heavy water to the conventional thermal circuit was detected, conducting the plant to a shut down. The development of a number of actions and measures were taken, in order to plug this leakage. The leakage was found in a heat exchanger, which is located in a place of difficult access, with a high radiological yield and which, according to design, it was not considered to be mechanically repaired. It is a U bend tubes heat exchanger, weighting about 20 tons, and with a heavy water flow of 800 tons/h on the primary circuit, and 950 tons/h of ordinary water on the secondary side. Foreseeing this event, it had been designed and constructed special equipment and procedures, by means of a contract, with the Company INVAP SA. Repair works were carried out within a period of eighty-six (86) days, from which, forty five days were used to repair the component itself. A considerable amount of time was used to prepare simulators and the training of personnel. Due to the high radiological yield and the strict care of radiological standards, it was necessary the participation of 300 persons, integrating a collective dose of 4,86 Sv-m. It was necessary the construction of platforms and auxiliary stairs so as to make the work place accessible, as well as lifting and movement devices for heavy components, since this area does not have such kind of facilities. Welding and cutting machines remote controlled as well as manipulators which operated in front of the exchanger tube sheet were used. The aim was the reduction of dose values as much as possible. Special shielding were developed and in some cases it was necessary the adoption of drastic measures such as the cutting of bolts or pipes. The failure was detected and the tube was plugged. Also were plugged those tubes with wall thickness

Controlling nuclear proliferation

International Nuclear Information System (INIS)

Sweet, W.

1981-01-01

Nuclear non-proliferation policy depends on the 1968 Non-Proliferation Treaty, in which countries promise not to acquire nuclear weapons in exchange for open access to peaceful nuclear technology, and a system of international safeguards that are imposed on exported nuclear equipment and facilities operated by parties to the treaty. Critics have feared all along that non-nuclear countries might circumvent or exploit the system to obtain nuclear weapons and that the Atoms for Peace plan would spread the very technology it sought to control. The nuclear weapons states would like everyone else to believe that atomic bombs are undesirable, but they continue to rely on the bombs for their own defense. Israel's raid on Iraq's nuclear reactor focused world attention on the proliferation problem and helped to broaden and sterengthen its prospects. It also highlighted the weakness that there are no effective sanctions against violators. Until the international community can ageee on enforcement measures powerful enough to prevent nuclear proliferation, individual countries may be tempted to follow Israel's example, 19 references

Electron capture rates in stars studied with heavy ion charge exchange reactions

Science.gov (United States)

Bertulani, C. A.

2018-01-01

Indirect methods using nucleus-nucleus reactions at high energies (here, high energies mean ~ 50 MeV/nucleon and higher) are now routinely used to extract information of interest for nuclear astrophysics. This is of extreme relevance as many of the nuclei involved in stellar evolution are short-lived. Therefore, indirect methods became the focus of recent studies carried out in major nuclear physics facilities. Among such methods, heavy ion charge exchange is thought to be a useful tool to infer Gamow-Teller matrix elements needed to describe electron capture rates in stars and also double beta-decay experiments. In this short review, I provide a theoretical guidance based on a simple reaction model for charge exchange reactions.

A new model for nuclear matter

International Nuclear Information System (INIS)

Skyrme, T.H.R.

1994-01-01

The different values obtained for nuclear radii from electromagnetic interactions as compared with specifically nuclear interactions suggested a model of nuclear matter in which the meson field is supposed to condense into an incompressible fluid and the nucleonic sources are confined to its interior by a strong interaction between the sources and the fluid as a whole. The sources are also coupled to spin and charge fluctuations in the fluid, whose exchange leads to further internucleonic forces. It is necessary to postulate that the fluid have a comparatively low density; as a result rotational levels of the fluid are high, leading to a small probability of exchange of angular momentum (and charge coupled to it) with the sources. The values of the anomalous electrical interactions of nucleons deduced are in rough agreement with the facts. The nuclear structure indicated is a shell model embedded in the mesic fluid whose oscillations, strongly coupled to the nucleons, give rise to the collective features of nuclear structure as in the theory of Bohr and Mottelson. It is suggested that this picture of the mesic field may indicate where to look for solutions of the meson field equations. (author). 9 refs

Inelastic J/Ψ photoproduction off nuclei: Gluon enhancement or double color exchange?

International Nuclear Information System (INIS)

Huefner, J.; Zamolodchikov, A.

1996-01-01

The nuclear enhancement observed in inelastic photoproduction of J/Ψ should not be interpreted as evidence for an increased gluon density in nuclei. The nuclear suppression of the production rate due to initial and final state interactions is calculated and a novel two-step color exchange process is proposed, which is able to explain the data. (orig.)

Nuclear power safety

International Nuclear Information System (INIS)

1988-01-01

The International Atomic Energy Agency, the organization concerned with worldwide nuclear safety has produced two international conventions to provide (1) prompt notification of nuclear accidents and (2) procedures to facilitate mutual assistance during an emergency. IAEA has also expanded operational safety review team missions, enhanced information exchange on operational safety events at nuclear power plants, and planned a review of its nuclear safety standards to ensure that they include the lessons learned from the Chernobyl nuclear plant accident. However, there appears to be a nearly unanimous belief among IAEA members that may attempt to impose international safety standards verified by an international inspection program would infringe on national sovereignty. Although several Western European countries have proposed establishing binding safety standards and inspections, no specific plant have been made; IAEA's member states are unlikely to adopt such standards and an inspection program

Correlations, nuclear structure, and DCX [double charge exchange

International Nuclear Information System (INIS)

Kaufmann, W.B.; Gibbs, W.R.; Arizona State Univ., Tempe, AZ

1989-01-01

To what extent can we understand current low-energy DCX cross sections to the DIAS in terms of the sequential mechanism? What do the results have to say about the nuclear wave functions? 20 refs., 20 figs

Fundamentals of nuclear chemistry

International Nuclear Information System (INIS)

Majer, V.

1982-01-01

The author of the book has had 25 years of experience at the Nuclear Chemistry of Prague Technical University. In consequence, the book is intended as a basic textbook for students of this field. Its main objectives are an easily understandable presentation of the complex subject and in spite of the uncertainty which still characterizes the definition and subjects of nuclear chemistry - a systematic classification and logical structure. Contents: 1. Introduction (history and definition); 2. General nuclear chemistry (physical fundamentals, hot atom chemistry, interaction of nuclear radiation with matter, radioactive elements, isotope effects, isotope exchange, chemistry of radioactive trace elements); 3. Methods of nuclear chemistry of nuclear chemistry (radiochemical methods, activation, separation and enrichment chemistry); 4. Preparative nuclear chemistry (isotope production, labelled compounds); 5. Analytival nuclear chemistry; 6. Applied nuclear chemistry (isotope applications in general physical and analytical chemistry). The book is supplemented by an annex with tables, a name catalogue and a subject index which will facilitate access to important information. (RB) [de

Theoretical studies in nuclear physics

International Nuclear Information System (INIS)

Landau, R.H.; Madsen, V.A.

1991-01-01

This report discusses: Imaginary Optical Potential; Isospin Effects; Scattering and Charge Exchange Reactions; Pairing Effects; bar K Interactions; Momentum Space Proton Scattering; Computational Nuclear Physics; Pion-Nucleus Interactions; and Antiproton Interactions

Meson exchange currents and two neutrino double beta decay

International Nuclear Information System (INIS)

Simkovic, F.

1995-01-01

By using a field theory approach a detailed analysis of the two neutrino double beta decay amplitude has been performed. We have shown that the summation over the intermediate nuclear states in the present two neutrino double beta decay studies corresponds to a summation over a class of meson exchange diagrams. We offer some arguments showing that the two nucleon mechanism considered at present does not provide the main contribution to the two neutrino double beta decay amplitude. A new electron-gamma exchange mechanism for this process is suggested. 31 refs., 1 fig

Extraction of Co ions from ion-exchange resin by supercritical carbon dioxide

International Nuclear Information System (INIS)

Ju, Min Su; Koh, Moon Sung; Yang, Sung Woo; Park, Kwang Heon; Kim, Hak Won; Kim, Hong Doo

2005-01-01

There are a number of liquid treatment processes for eliminating radioactive ionic contaminants in nuclear facilities. One of the most common treatment methods for aqueous streams is the use of ion exchange, which is a well-developed technique that has been employed for many years in the nuclear industry. More specifically speaking, systems that ion exchange method is applied to in nuclear power plants are liquid radioactive waste treatment system, chemical and volume control system, steam generator blowdown treatment system, and service water supply system. During the operation of nuclear power plants, radioactive contaminants such as Co-60, Mn-54, Fe-59 and Cs-137 are contained in liquid radioactive wastes. And the wastes containing small amount of uranium are generated in nuclear fuel cycle facilities. To treat the liquid radioactive waste, we usually install ion exchangers rather than evaporators due to their simplicity and effectiveness, and this trend is increasing. However, the ion exchange process produces large volume of spent organic resin, and has some problems of radiation damage and thermal instability. And the reuse of the resin is limited due to the degradation of ion-exchanging ability. For this reason, were should consider a better method to expand the lifetime of the resin or to reduce the volume of radioactive resin wastes by extracting radioactive contaminants located in the resin. Supercritical fluid CO 2 has many good points as a process solvent that include low viscosity, negligible surface tension, and variable selectivity. And supercritical fluids have physical properties of both liquid and gas such as good penetration with a high dissolution capability. Supercritical fluids have been widely used in extraction, purification, and recovery processes. A number of workers applied supercritical CO 2 solvent for cleaning of precision devices and waste treatments. Since supercritical CO 2 has its mild critical point at 31 and 73.8bar as .deg. C

Is nuclear structure relevant to non-mesonic hyper-nuclear weak decay?

International Nuclear Information System (INIS)

Wu, H.C.; Aristizabal, M.F.; Ponce, W.A.

2002-01-01

This work studies the relevance of nuclear structure in the non-mesonic weak decay of Λ-hypernuclei, with the mechanism of ΛN → NN transition being restricted to one pion exchange (OPE) only. As an application, for the hypernucleus Λ 12 C a comparison between the L-S coupling and the j-j coupling gives an estimate of the range of nuclear structure effects. A considerable dependence is found of the total decay rate and the ratio Γ n /Γ p on the single particle properties of nuclear models. The possible contribution from the ΔI = 3/2 channel is investigated in a phenomenological manner. (author)

Manufacture of heat exchangers

International Nuclear Information System (INIS)

Burton, J.E.; Tombs, R.W.T.

1980-01-01

A tube bundle for use in a heat exchanger has a series of spaced parallel tubes supported by tube plates and is manufactured by depositing welding material around the end of each tube, machining the deposited material to form an annular flange around the end of the tube and welding the flange into apertures in the tube plate. Preferably the tubes have a length which is slightly less than the distance between the outer surfaces of the tube plates and the deposited material is deposited so that it overlaps and protects the end surfaces of the tubes. A plug may be inserted in the bore of the tubes during the welding material deposition which, as described, is effected by manual metal arc welding. One use of heat exchangers incorporating a tube bundle manufactured as above is in apparatus for reducing the volume of, and recovering nitric acid from, radioactive effluents from a nuclear reprocessing plant. (author)

Nuclear information and knowledge, No. 7, June 2009

International Nuclear Information System (INIS)

Lecossois, B.

2009-06-01

This bi-annual newsletter reports on the activities of the INIS and Nuclear Knowledge Management Section of the IAEA Department of Nuclear Energy. Issue no. 7 is centred on cooperation and partnerships in nuclear information, focusing specifically on two international networks coordinated by the IAEA's nuclear information and knowledge management services: the International Nuclear Information System (INIS) and the International Nuclear Libraries Network (INLN). Table of contents : To our Readers; INIS and International Cooperation in Nuclear Information; INLN: Facilitating Exchange and Building Partnerships; News from INIS and NKM; Recent Publications; IAEA Library Update; 2009 Meetings

76 FR 73721 - Nine Mile Point Nuclear Station, LLC, Nine Mile Point Nuclear Station, Unit No. 2, Environmental...

Science.gov (United States)

2011-11-29

.... Solid radioactive waste streams include filter sludge, spent ion exchange resin, and dry active waste... Environmental Impact of Transportation of Fuel and Waste to and from One Light-Water-Cooled Nuclear Power... facilities. NMP2 uses a boiling-water reactor and a nuclear steam supply system designed by General Electric...

On-line fouling monitor for heat exchangers

International Nuclear Information System (INIS)

Tsou, J.L.

1995-01-01

Biological and/or chemical fouling in utility service water system heat exchangers adversely affects operation and maintenance costs, and reduced heat transfer capability can force a power deaerating or even a plant shut down. In addition, service water heat exchanger performance is a safety issue for nuclear power plants, and the issue was highlighted by NRC in Generic Letter 89-13. Heat transfer losses due to fouling are difficult to measure and, usually, quantitative assessment of the impact of fouling is impossible. Plant operators typically measure inlet and outlet water temperatures and flow rates and then perform complex calculations for heat exchanger fouling resistance or ''cleanliness''. These direct estimates are often imprecise due to inadequate instrumentation. Electric Power Research Institute developed and patented an on-line condenser fouling monitor. This monitor may be installed in any location within the condenser; does not interfere with routine plant operations, including on-line mechanical and chemical treatment methods; and provides continuous, real-time readings of the heat transfer efficiency of the instrumented tube. This instrument can be modified to perform on-line monitoring of service water heat exchangers. This paper discusses the design, construction of the new monitor, and algorithm used to calculate service water heat exchanger fouling

Solidification of 137Cs into potassium cobalt hexacyanoferrate (II) ion exchanger

International Nuclear Information System (INIS)

Lehto, J.; Harjula, R.; Haukka, S.; Wallace, J.

1989-01-01

An inorganic ion exchange, potassium cobalt hexacyanoferrate(II), has been studied for the separation of 137 Cs from nuclear waste solutions. This exchanges is highly selective for cesium over other alkali metal ions and can be synthesized in granular form suitable for column operations. Pilot-plant experiments were carried out at a NPP to test the exchanges for solidification of 137 Cs from an evaporator concentrate. The results were encouraging: decontamination factors and volume reduction factors were both very high. A full-scale separation plant is now under construction plans call for the exchanges, loaded with 137 Cs, to be disposed of in stainless steel columns, sealed by welding and enclosed in concrete block. According to the authors this multibarrier procedure provides a safe final disposal solution

Hyperon interaction in free space and nuclear matter within a SU(3) based meson exchange model

Energy Technology Data Exchange (ETDEWEB)

Dhar, Madhumita

2016-06-15

To establish the connection between free space and in-medium hyperon-nucleon interactions is the central issue of this thesis. The guiding principle is flavor SU(3) symmetry which is exploited at various levels. In first step hyperon-nucleon and hyperon- hyperon interaction boson exchange potential in free space are introduced. A new parameter set applicable for the complete baryon octet has been derived leading to an updated one-boson- exchange model, utilizing SU(3) flavor symmetry, optimizing the number of free parameters involved, and revising the set of mesons included. The scalar, pseudoscalar, and vector SU(3) meson octets are taken into account. T-matrices are calculated by solving numerically coupled linear systems of Lippmann-Schwinger equations obtained from a 3-D reduced Bethe-Salpeter equation. Coupling constants were determined by χ{sup 2} fits to the world set of scattering data. A good description of the few available data is achieved within the imposed SU(3) constraints. Having at hand a consistently derived vacuum interaction we extend the approach next to investigations of the in-medium properties of hyperon interaction, avoiding any further adjustments. Medium effect in infinite nuclear matter are treated microscopically by recalculating T-matrices by an medium-modified system of Lippmann-Schwinger equations. A particular important role is played by the Pauli projector accounting for the exclusion principle. The presence of a background medium induces a weakening of the vacuum interaction amplitudes. Especially coupled channel mixing is found to be affected sensitively by medium. Investigation on scattering lengths and effective range parameters are revealing the density dependence of the interaction on a quantitative level.

Liquid radioactive waste processing improvement of PWR nuclear power plants; Melhorias no processamento de rejeitos liquidos radioativos de usinas nucleares PWR

Energy Technology Data Exchange (ETDEWEB)

Nery, Renata Wolter dos Reis; Martinez, Aquilino Senra; Monteiro, Jose Luiz Fontes [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear]. E-mail: wolter@eletronuclear.gov.br; monteiro@peq.coppe.ufrj.br; aquilinosenra@lmp.ufrj.br

2005-07-01

The study evaluate an inorganic ion exchange to process the low level liquid radwaste of PWR nuclear plants, so that the level of the radioactivity in the effluents and the solid waste produced during the treatment of these liquid radwaste can be reduced. The work compares two types of ion exchange materials, a strong acid cation exchange resin, that is the material typically used to remove radionuclides from PWR nuclear plants wastes, and a mordenite zeolite. These exchange material were used to remove cesium from a synthetic effluent containing only this ion and another effluent containing cesium and cobalt. The breakthrough curves of the zeolite and resin using a fix bed reactor were compared. The results demonstrated that the zeolite is more efficient than the resin in removing cesium from a solution containing cesium and cobalt. The results also showed that a bed combining zeolite and resin can process more volume of an effluent containing cesium and cobalt than a bed resin alone. (author)

Development of Design Criteria for Fluid Induced Structural Vibrations in Steam Generators and Heat Exchangers

International Nuclear Information System (INIS)

Uvan Catton; Dhir, Vijay K.; Deepanjan Mitra; Omar Alquaddoomi; Pierangelo Adinolfi

2004-01-01

Flow-induced vibration in heat exchangers has been a major cause of concern in the nuclear industry for several decades. Many incidents of failure of heat exchangers due to apparent flow-induced vibration have been reported through the USNRC incident reporting system. Almost all heat exchangers have to deal with this problem during their operation. The phenomenon has been studied since the 1970s and the database of experimental studies on flow-induced vibration is constantly updated with new findings and improved design criteria for heat exchangers

Nuclear Society of Russia: Ten years in the world nuclear community

Energy Technology Data Exchange (ETDEWEB)

Ponomarev-Stepnoi, N.N.; Gagarinski, A.Yu.

2000-07-01

the analysis of nuclear energy production trends and--most importantly for relations with the mass media and the public--crisis information (latest examples: Tokaimura, the virtual Y2K crisis, etc.), have become important sources of information for the NSR. It should be emphasized that the financial participation of the Russian Minatom (maintained at the insistent request of the NSR) in the NucNet system provides sufficiently wide dissemination of operative nuclear information not only through the NSR headquarters but also via its regional branches and separate enterprises. From its side, NSR has assumed the responsibility for the adequate flow of information on Russian nuclear events to NucNet. As a living and developing organism, the NSR wants to respond to its time's challenges. Several prospective directions could be among the NSR information exchange plans: (1) Independent international analysis of the problems of the use of nuclear energy, which is presently in a stagnation period but with future large-scale development, is as possible today as it never had been before. (2) In the field of public relations, many achievements of Russian and US specialists (in the form of articles, analyzing nuclear energy on the popular and highly professional level) stay inaccessible to others because of the language barrier. A possible joint ANS/NSR project on selection, translation, and exchange of such materials, with their further wide publication, represents an obvious reserve in their societies' information activities. (3) The International Youth Nuclear Congress project (proposed by the Russian nuclear youth and supported by ANS and ENS), conceived as a bridge between generations and a forum for opinion exchange between young nuclear specialists from various countries, deserves further development and appropriation of permanent status in the activities of the world nuclear societies.

Numerical Study of Condensation Heat Exchanger Design in a Subcooled Pool: Correlation Investigation

International Nuclear Information System (INIS)

Lee, Hee Joon; Ju, Yun Jae; Kang, Han Ok; Lee, Tae Ho; Park, Cheon Tae

2012-01-01

Generally the condensation heat exchanger has higher heat transfer coefficient compared to the single phase heat exchanger, so has been widely applied to the cooling systems of energy plant. Recently vertical or horizontal type condensation heat exchangers are being studied for the application to secondary passive cooling system of nuclear plants. Lee and Lee investigated the existing condensation correlation to the experiment for heat exchanger in saturated pool. They concluded Traviss' correlation showed most satisfactory results for the heat transfer coefficient and mass flow rate in a saturated water pool. In this study, a thermal sizing program of vertical condensation heat exchanger to design, TSCON(Thermal Sizing of CONdenser) was validated with the existing experimental data of condensation heat exchanger in a subcooled pool for pure steam condensation

Quantitative chemical exchange saturation transfer with hyperpolarized nuclei (qHyper-CEST): sensing xenon-host exchange dynamics and binding affinities by NMR.

Science.gov (United States)

Kunth, M; Witte, C; Schröder, L

2014-11-21

The reversible binding of xenon to host molecules has found numerous applications in nuclear magnetic resonance studies. Quantitative characterization of the Xe exchange dynamics is important to understand and optimize the physico-chemical behavior of such Xe hosts, but is often challenging to achieve at low host concentrations. We have investigated a sensitive quantification technique based on chemical exchange saturation transfer with hyperpolarized nuclei, qHyper-CEST. Using simulated signals we demonstrated that qHyper-CEST yielded accurate and precise results and was robust in the presence of large amounts of noise (10%). This is of particular importance for samples with completely unknown exchange rates. Using these findings we experimentally determined the following exchange parameters for the Xe host cryptophane-A monoacid in dimethyl sulfoxide in one type of experiment: the ratio of bound and free Xe, the Xe exchange rate, the resonance frequencies of free and bound Xe, the Xe host occupancy, and the Xe binding constant. Taken together, qHyper-CEST facilitates sensitive quantification of the Xe exchange dynamics and binding to hydrophobic cavities and has the potential to analyze many different host systems or binding sites. This makes qHyper-CEST an indispensable tool for the efficient design of highly specific biosensors.

Suppressing magnetization exchange effects in stimulated-echo diffusion experiments.

Science.gov (United States)

Pagès, Guilhem; Dvinskikh, Sergey V; Furó, István

2013-09-01

Exchange of nuclear magnetization between spin pools, either by chemical exchange or by cross-relaxation or both, has a significant influence on the signal attenuation in stimulated-echo-type pulsed field gradient experiments. Hence, in such cases the obtained molecular self-diffusion coefficients can carry a large systematic error. We propose a modified stimulated echo pulse sequence that contains T2-filters during the z-magnetization store period. We demonstrate, using a common theoretical description for chemical exchange and cross-relaxation, that these filters suppress the effects of exchange on the diffusional decay in that frequent case where one of the participating spin pools is immobile and exhibits a short T2. We demonstrate the performance of this experiment in an agarose/water gel. We posit that this new experiment has advantages over other approaches hitherto used, such as that consisting of measuring separately the magnetization exchange rate, if suitable by Goldman-Shen type experiments, and then correcting for exchange effects within the framework of a two-site exchange model. We also propose experiments based on selective decoupling and applicable in systems with no large T2 difference between the different spin pools. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Accuracy in the quantification of chemical exchange saturation transfer (CEST) and relayed nuclear Overhauser enhancement (rNOE) saturation transfer effects.

Science.gov (United States)

Zhang, Xiao-Yong; Wang, Feng; Li, Hua; Xu, Junzhong; Gochberg, Daniel F; Gore, John C; Zu, Zhongliang

2017-07-01

Accurate quantification of chemical exchange saturation transfer (CEST) effects, including dipole-dipole mediated relayed nuclear Overhauser enhancement (rNOE) saturation transfer, is important for applications and studies of molecular concentration and transfer rate (and thereby pH or temperature). Although several quantification methods, such as Lorentzian difference (LD) analysis, multiple-pool Lorentzian fits, and the three-point method, have been extensively used in several preclinical and clinical applications, the accuracy of these methods has not been evaluated. Here we simulated multiple-pool Z spectra containing the pools that contribute to the main CEST and rNOE saturation transfer signals in the brain, numerically fit them using the different methods, and then compared their derived CEST metrics with the known solute concentrations and exchange rates. Our results show that the LD analysis overestimates contributions from amide proton transfer (APT) and intermediate exchanging amine protons; the three-point method significantly underestimates both APT and rNOE saturation transfer at -3.5 ppm (NOE(-3.5)). The multiple-pool Lorentzian fit is more accurate than the other two methods, but only at lower irradiation powers (≤1 μT at 9.4 T) within the range of our simulations. At higher irradiation powers, this method is also inaccurate because of the presence of a fast exchanging CEST signal that has a non-Lorentzian lineshape. Quantitative parameters derived from in vivo images of rodent brain tumor obtained using an irradiation power of 1 μT were also compared. Our results demonstrate that all three quantification methods show similar contrasts between tumor and contralateral normal tissue for both APT and the NOE(-3.5). However, the quantified values of the three methods are significantly different. Our work provides insight into the fitting accuracy obtainable in a complex tissue model and provides guidelines for evaluating other newly developed

INDC correspondents for the exchange of nuclear data information

International Nuclear Information System (INIS)

1983-05-01

This list serves as a basis for the distribution of documents originated by or for the International Nuclear Data Committee and includes the names of all recipients of INDC documents. The INDC Secretariat tries to maintain this list up-to-date in order to facilitate an efficient interchange of information on nuclear data topics. In this report, the names are listed in alphabetical order within each state or organization. The main list is followed by four shorter lists, indicating the names of individuals in each distribution category, and the total number of individuals in each category

Studies on the incorporation of spent ion exchange resins from nuclear power plants into bitumen and cement

International Nuclear Information System (INIS)

Bonnevie-Svendsen, M.; Tallberg, K.; Aittola, P.; Tollbaeck, H.

1976-01-01

The joint Nordic incorporation experiments should provide technical data needed for the assessment of solidification techniques for wastes from nuclear reactors in the Nordic countries. Spent ion exchange resins are a main fraction of such wastes, and more knowledge about their incorporation is wanted. The effects of simulated and real ion exchange wastes on the quality of bitumen and cement incorporation products were studied. Blown and distilled bitumen and three Portland cement qualities were used. Product characterizations were based on properties relevant for safe waste management, storage, transport and disposal. The applicability and relevance of established and suggested tests is discussed. Up to 40-60% dry resin could be incorporated into bitumen without impairing product qualities. Products with higher resin contents were found to swell in contact with water. The products had a high leach resistance. Their form stability was improved by incorporated resins. Product qualities appeared to be less affected by physico-chemical variables than by mechanical process parameters. Pure resin-cement products tend to decompose in water. Product qualities were strongly affected by a variety of physico-chemical process parameters, and integer products were only obtained within narrow tolerance limits. Caesium was rapidly leached out. To attain integer products and improved leach resistance within technically acceptable tolerance limits it was necessary to utilize stabilizing and caesium-retaining additives such as Silix and vermiculite. Under the present conditions the water content of the resins limited the amounts that could be incorporated in 40-50wt% or about 70vol.% water-saturated (containing 20-40% dry) resin. (author)

Semiautomatic exchanger of samples for carry out neutron activation analysis