Energy Technology Data Exchange (ETDEWEB)

In this article a production method of a magnetorheological suspension composed with silicon steel particles of size 0.1-0.15 mm and 4% silicon content is described. Steel particles were dispersed in a conducting carrier of a by mixture of graphite particles with size 2-5 {mu}m and cedar wood oil. The filling factor of the suspension with the silicon steel particles and with graphite particles amounted to 0.25-0.40. Samples of this suspension were placed in a rectangular vessel with electrodes and used for the investigation of the Hall effect in magnetic field with induction 0-8 T, generated by Bitter-type magnet. A non-linear dependence of Hall voltage on the induction of the applied magnetic field and a hysteresis loop of this voltage in the shape of inclined digit eight were found. The causes of the observed effects is the ordering of silicon steel particles and graphite particles along the side of magnetic field lines.

International Nuclear Information System (INIS)

This item covers a meeting held between members of the United Kingdom government's energy committee and representatives of British Nuclear Fuels (BNFL) to discuss their Annual Report and Accounts for the year 1988-89. The committee explored the reasons for escalating predictions of the costs of nuclear power and why decommissioning costs are so difficult to estimate accurately so as to include them in cost per kilowatt hour of generated electricity. The relationship between BNFL and the Ministry of Defence (MoD) was explored, as was the MoD's relationship with the United States Department of Defense. BNFL's financial position should improve when the thermal oxide reprocessing plant at Sellafield becomes operational, and the Chapelcross and Calder Hall reactors may contribute income from electricity generation. (UK).

International Nuclear Information System (INIS)

Available data are presented which support the supposition that metals and alloys with a negative low-temperature Hall coefficient are apparently not superconducting. (author).

Energy Technology Data Exchange (ETDEWEB)

The theoretical analysis of a partially-ionized hydrogen gas flow (gas temperatures of approximately 10,000 to 20,000 K) through a particular class of magnetohydrodynamic (MHD) generators and the preliminary design of these MHD generators as open cycle, electric power supplies are performed. Analysis of the gas flow through these ultra-high temperature MHD generators requires a coupled gas dynamics/radiative heat transfer solution. Gas dynamics are modeled by a set of quasi-one-dimensional, nonlinear differential equations which account for friction, convective and radiative heat transfer and the interaction between the ionized gas and applied magnetic field. Radiative heat transfer is modeled using non-gray, absorbing-emitting two- and three-dimensional P-1 approximations which permit an arbitrary variation of the spectral absorption coefficient with frequency. Gas dynamics and radiative heat transfer are coupled through ...

International Nuclear Information System (INIS)

Nuclear energy plays an important role in electricity generation, producing 16% of the world's electricity at the beginning of 1999. It has proven to be safe, reliable, economical and has only a minimal impact on the environment. Most of the world's energy consumption, however, is in the form of heat. The market potential for nuclear heat was recognized early. Some of the first reactors were used for heat supply, e.g. Calder Hall (United Kingdom), Obninsk (Russian Federation), and Agesta (Sweden). Now, over 60 reactors are supplying heat for district heating, industrial processes and seawater desalination. But the nuclear option could be better deployed if it would provide a larger share of the heat market. In particular, seawater desalination using nuclear heat is of increasing interest to some IAEA Member States. In consideration of the growing experience being accumulated, the IAEA periodically reviews the progress and new developments in ...

Science.gov (United States)

Apr 9, 2003 ... Adam Kissiah Jr., a retired KSC engineer, will be honored for his development of the digital hearing aid technology that led to the cochlear ...

Energy Technology Data Exchange (ETDEWEB)

The properties of Mn-doped GaAs layers grown by laser deposition were investigated with measurements of Hall effect and magneto-optical Kerr effect (MOKE). The electrical and magnetic parameters of the layers were defined by growth temperature and quantity of sputtered Mn. It was shown that room-temperature ferromagnetism is revealed by MOKE and, after ruby laser 25 ns pulse annealing, by Hall effect measurements.

International Nuclear Information System (INIS)

The electrical resistivity, Hall effect, and magnetic susceptibility of single-crystal UPd_2Si_2 have been studied between 4.2 and 300 K. A large anisotropy was observed in both the magnetic and transport properties. There is a quadratic temperature dependence of the resistivity for a range of temperatures between 4.2 and 80 K. At higher temperatures, the resistivity indicates a Kondo-type behavior. The behavior of these quantities is accounted for by the magnetic phase transitions at 108 and 136 K reported from neutron-scattering studies. At high temperatures, the magnetic susceptibility of UPd_2Si_2 is Curie-Wiess-like along the c axis. The temperature dependence of the Hall coefficient above 108 K is accounted for by a theoretical model invoking skew scattering of conduction electrons by localized magnetic moments.

British Library Electronic Table of Contents (United Kingdom)

The present investigation is concerned with the effect of Hall currents on boundary layer flow, and heat and mass transfer of an electrically conducting fluid over an unsteady stretching sheet in the presence of a strong magnetic field. The electron-atom collision frequency is assumed to be relatively high, so that the Hall effect is assumed to exist, while the induced magnetic field is neglected. The governing time-dependent boundary layer equations for momentum, thermal energy, and concentration are reduced using a similarity transformation to a set of coupled ordinary differential equations. The similarity ordinary differential equations are then solved numerically by the successive linearization method together with the Chebyshev pseudo-spectral collocation method. Effects of the Prand...

Science.gov (United States)

Thermal Cavity Receivers,". JPL. Publication. 83-97,. 1983. 5Hall, III, C.A., Glakpe, E.K., Cannon,. J.N., and. Kerslake,. T.W., "Modeling ...

Science.gov (United States)

on the picture will download the highest resolution version available. M51: The Whirlpool Galaxy Credit: W. Keel (U. Alabama), 1.1-meter Hall Telescope, Lowell Observatory...

Science.gov (United States)

nt method for the Stefan problem, Int. J. Num. Meth. in . . (25) G. STKANG AND G.J. FIX, A n v s i s of the F U L L. Element, Prentice-Hall, 1973. ...

Energy Technology Data Exchange (ETDEWEB)

A working visit was made to the National Laboratory for High Energy Physics, Tsukuba, Japan, during the time periods May 16, 1988--June 15, 1988 for the purposes of further evaluation of the high intensity plasma sputter negative ion source and to test the response of the University of Tsukuba 13-MV tandem accelerator to mA intensity level pulsed mode heavy negative ion beams. During the visit, the traveler worked in collaboration with Japanese scientists in installing and testing of the source on the University of Tsukuba tandem electrostatic accelerator injector. During the course of preliminary testing of the ion source and prior to actual injection into the accelerator, sparking began in one or more tube sections, which ultimately led to the decision to replace the damaged tube sections. This problem led to postponement of the scheduled tandem accelerator tests. The traveler attended the Seventh International Conference on Ion Implantation Technology held in the International ...

International Nuclear Information System (INIS)

In the early sixties it was decided to investigate salt formations on its suitability to host heat generating radioactive waste in Germany. In the reference repository concept consequently the emplacement of vitrified waste canisters in deep vertical boreholes inside a salt mine was considered whereas spent fuel should be disposed of in self shielding casks (type POLLUX) in horizontal drifts. The POLLUX casks, 65 t heavy carbon steel casks, will be laid down on the floor of a horizontal drift in one of the disposal zones to be constructed in the salt dome at the 870 m level. The space between casks and drift walls will be backfilled with crushed salt. The transport, the handling und the emplacement of POLLUX casks were subject of successfully performed demonstration and in situ tests in the nineties and resulted in an adjustment of the atomic law. The borehole disposal concept comprises the emplacement of unshielded canisters with vitrified HLW in boreholes with a ...

International Nuclear Information System (INIS)

NiMnSb has attracted a great deal of interest as a spin injector/detector in spintronic devices because it has a Curie temperature of 728 K and is predicted to be half-metallic (100% spin polarized). NiMnSb has been reported to have greatly reduced surface polarization, and to lose its half metallicity above 80 K. Here we report the investigation of the surface polarisation and electronic structure of NiMnSb by measurement of the transport spin polarization using point contact Andreev reflection spectroscopy, and anomalous Hall effect in thin films on Si(0 0 1). A comparison to bulk properties is made.

Energy Technology Data Exchange (ETDEWEB)

We present a systematic study of the magnetization, Hall effect and specific heat on single crystals of Mn{sub 4}Si{sub 7}. Curie-Weiss law is observed above 43 K. At low-temperature moments order in an anisotropic helical state and are aligned above 1 T. We observe an anomalous Hall effect in both {rho}{sub H} vs. B and in R{sub H} vs. T curves and a field dependence of the low T specific heat due to spin fluctuations. The magnetic moments (p{sub eff} and p{sub sat}) are the lowest reported for similar itinerant magnetic systems, this suggests that Mn{sub 4}Si{sub 7} is a good candidate to observe critical quantum fluctuations expected for a marginal Fermi liquid.

Energy Technology Data Exchange (ETDEWEB)

Virtual Compton Scattering o013 the proton has been studied at Q 2 -values of 1:0 and 1:9 (GeV=c) 2 in Hall A at the Thomas Je013erson National Accelerator Facility (JLab). Data were taken below and above the pion production threshold as well as in the resonance region. Results obtained below pion threshold at Q 2 = 1:0 (GeV=c) 2 are presented in this paper.

Wastenet

... Indoor facilities include a 50 metre swimming pool, various sports halls, a netball and badminton centre, a dance studio, a high performance athletics centre, the ECB National Cricket Academy, and the National Gymnastics Performance and Research Centre, whilst outdoors there are floodlit all-weather areas, a water-based ...

International Nuclear Information System (INIS)

The modular and periodic antenna structure in TCA is shown to produce an extremely pure spectrum of excited waves. This purity, together with precise measurements of the antenna loading in different parts of the spectrum, has allowed us to demonstrate that it is essential to include both toroidal coupling and the Hall effect (#omega#/#omega#/sub c//sub i/not =0) in order to explain our results. We show that toroidicity produces coupling from the directly excited Vertical BarmVertical Bar = 1 wave to Vertical BarmVertical Bar = 0,2 waves. Discrete Alfven Waves are also seen for Vertical BarmVertical Bar = 0,2 in addition to the directly driven Vertical BarmVertical Bar = 1. The importance of the Hall effect is most visible when a travelling wave is excited, in which case the antenna loading depends on the direction of the wave imposed. We present the antenna loading found with different excitation structures and discuss the implications on the ...

CERN Document Server

In this paper we analyze the Hilbert boundary-value problem of the theory of analytic functions for an $(N+1)$-connected circular domain. An exact series-form solution has already been derived for the case of continuous coefficients. Motivated by the study of the Hall effect in a multiply connected plate we extend these results by examining the case of discontinuous coefficients. The Hilbert problem maps into the Riemann-Hilbert problem for symmetric piece-wise meromorphic functions invariant with respect to a symmetric Schottky group. The solution to this problem is derived in terms of two analogues of the Cauchy kernel, quasiautomorphic and quasimultiplicative kernels. The former kernel is known for any symmetry Schottky group. We prove the existence theorem for the second, quasimultiplicative, kernel for any Schottky group (its series representation is known for the first class groups only). We also show that the use of an automorphic kernel requires the ...

International Nuclear Information System (INIS)

The Daya Bay reactor neutrino experiment is located at the Daya Bay nuclear power plant in Shenzhen, China. The experiment deploys eight 'identical' antineutrino detectors to measure antineutrino fluxes from six 2.9 GWth reactor cores in three underground experimental halls at different distances. The target zone of the Daya Bay detector is filled with 20 t 0.1% Gd doped LAB liquid scintillator. The baseline uncorrelated detector uncertainty is ?0.38% using current experimental techniques. Daya Bay can reach a sensitivity of sin22?13<0.01 with baseline uncertainties after 3 years of data taking.

International Nuclear Information System (INIS)

Since 1976 the Austrian Research Centre Seibersdorf has the task to collect, treat and store radioactive waste (Radwaste) arising in Austria. Within the Department of Waste Management a variety of appropriate treatment systems are installed. For storing unconditioned and conditioned waste proper storage-halls are available. The collection of Radwaste is carried out using 100 l drums, for the conditioned waste the 200 l drum concept is used. The interim storage of conditioned waste is done at Seibersdorf until a final repository is built. The present plan foresees one to be in operation at the year 2012. (author).

Energy Technology Data Exchange (ETDEWEB)

In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated water retention capacity of a fusion reactor concrete building. Using a model of the tritiated water diffusion determined form experimental results, depth profiles of tritiated water in concrete are calculated in the case of being exposed to air containing tritiated water vapor during the normal operational condition of a fusion reactor. A 0.5-m-thick concrete is sufficient for reactor hall walls from a viewpoint of the tritium containment.

British Library Electronic Table of Contents (United Kingdom)

In Korea, the Proton Engineering Frontier Project (PEFP) is building a proton linear accelerator facility with energy up to 100MeV and a beam current of 20mA. In this study, a radiation field after shutdown in the accelerator facility of the PEFP was evaluated for the purpose of the radiation shielding by using MCNPX code. A facility modeling was performed for the accelerator tunnel building, accelerator chain, target rooms and beam experiment hall. And radiation source terms were evaluated in the facility. With this facility, model and radiation source terms, the concentration of 41Ar was evaluated and the cooling time satisfying regulation in Korea was calculated.

Energy Technology Data Exchange (ETDEWEB)

Many industrial workshops in Germany were erected during the 40s and 50s, especially at the beginning of the economic boom. After more than 40 years, these facilities are in need of structural and production-technical modernization. A case in point is the carriage fabrication workshop of the Salzgitter-based company Linke-Hoffmann-Busch. The characteristic features of this type of building are large glazed areas, free uncontrolled ventilation and substantial height. Opportunities for energy-oriented and light-technical modernization are demonstrated at this Salzgitter workshop in exemplary form, the emphasis being on the use of solar energy components and, particularly, transparent thermal insulation. (orig.) [Deutsch] In der Bundesrepublik Deutschland gibt es viele Produktionshallen, die in den vierziger und fuenfziger Jahren, insbesondere zu Beginn des wirtschaftlichen Aufschwungs, errichtet wurden. Diese Hallen sind nach ueber vierzig Jahren sowohl aus baulichen als auch ...

Energy Technology Data Exchange (ETDEWEB)

Conductivity and Hall effect measurements were made in dark and IR-photoexcited p-type ZnTe samples between 77 and 300 K. Acceptor vacancy complexes of activation energies 0.09-0.1 eV were found to be present in the photoexcited samples. Different possible scattering mobilities were considered for both samples to explain the observed hole mobility. In the photoexcited sample a scattering mobility due to vacancy complexes was suggested for the first time to explain the results. The scattering centres were associated with native vacancy complexes segregated at the dislocations sites. The expression for the complex scattering mobility has been deduced using the curve fitting method to be {mu}{sub C}=(6.6x10{sup -11})T{sup 5} e{sup 725/T}. (orig.).

Science.gov (United States)

Cadmium telluride single crystals were grown heavily doped with chloride by the THM method. The resulting crystals were n-type with free carrier concentrations of the order of 10('12)/cm at room temperature. Hall effect studies revealed room temperature mobilities between 30 and 350 cm('2)/v-sec and resistivites between 2 x 10('3) and 10('4) ohm-cm. Studies were made of the gamma and alpha counting characteristics of these crystals with metal, metal-semiconductor, and metal-insulator electrodes. It was found that the MIS and MSS structures resulted in significant improvement over the MS structures in counting, signal-to-noise and energy resolution.

British Library Electronic Table of Contents (United Kingdom)

Given the widely accepted notion of whole person education in Confucian societies such as Hong Kong, Mainland China and Singapore, it is surprising that research literature originated in these societies pays little attention to how students learn and develop through out-of-class experiences at university. There is little research evidence on how the prevailing culture among student social communities (residential halls and student societies/clubs) influences students? social involvement and development. This paper examines 42 Chinese students? social experiences and development during their freshman year at a Hong Kong university. The majority of them were intensively involved in out-of-class activities. Their active social involvement was both a response to the culture of student communit...

CERN Document Server

We present a proposal for a combined ICARUS & NOE general purpose detector, to be installed in Hall B of the Gran Sasso Laboratory.The main scientific goal is the one of elucidating in a comprehensive way the pattern of neutrino $9 masses and mixings, following both (1) the S-KAM results and (2) the predictions on atmospheric neutrinos of the large solution of the Solar Neutrinos deficit. To achieve these goals, the experimental method is based upon the $9 complementary and simultaneous detection of CERN beam (CNGS) and cosmic ray (CR) events. This is made possible because of the complete isotropy of the detection technique. For the currently allowed values of the S-KAM results, both $9 CNGS and cosmic ray data will give independent measurements and provide a precise $(sin^{2}2\\theta; \\Delta m^{2})$ determination rather than a wide band of allowed values. Since we can observe and unambiguously identify $9 $\

International Nuclear Information System (INIS)

AM-SC1 is a heat treatable magnesium alloy that has been specifically developed to achieve the elevated temperature strength and creep properties necessary for engine block applications. This paper describes the interrelationship between the microstructure and the mechanical properties of AM-SC1. The compressive and tensile strengths are relatively insensitive to temperature up to and including 450 K and the tensile yield behaviour deviates from a standard Hall-Petch relationship at grain sizes below 200 ?m. The microstructural features contributing to the creep resistance are both inter- and intra-granular in nature and are on length scales from nanometers to micrometers. The creep behaviour at 423 K and 450 K is diffusion controlled, with any contribution from the grain boundaries being negligible.

Energy Technology Data Exchange (ETDEWEB)

In this study we discuss an unsteady free convection MHD flow past semi-infinite vertical porous plate. We have considered the flow in the presence of a strong magnetic field and therefore the electromagnetic force is very large. This brings in the phenomenon of Hall and Ion-slip currents. The effects of these two parameters together with that of viscous dissipation and radiation absorption among others on velocity, temperature and concentration profiles are presented. The profiles are presented graphically. As the partial differential equations governing this problem are highly non-linear they are solved numerically by a finite difference method. It is found that in presence of heating of the plate by free convection current the velocity boundary layer thickness decreases.

CERN Document Server

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

International Nuclear Information System (INIS)

Fibre-reinforced-polymer-composite material has been suggested as a bearing material to overcome tribological problems witnessed during the testing of Ram assembly of the 540 MWe fuelling machine at RTD. After successful trials at B-Ram the composite material has been adapted for B-RAM, C-Ram and RDB head at fuelling machines being tested at RTD, Hall 7 and at Tarapur. Laboratory evaluations were also carried out at Tribology Lab RTD to study effect of radiation on the composite. Paper deals with the various aspects of life prediction of this material in term of wear and radiation damage. (author)

International Nuclear Information System (INIS)

The dependence of the carrier concentrations, of the resistivity and of the Hall coefficient of irradiated silicon on the neutron fluences has been investigated, starting from the supposition that the main phenomena induced by irradiation in the semiconductor bulk are shallow-donor removal and deep-centres creation. The free parameters of the model are initial doping of the starting material, the permitted energy level values of the radiation-induced centres in the semiconductor band gap and their introduction rates. The influence of each parameter on the calculated dependences is studied in detail, for three cases: one deep acceptor-like centre, two deep acceptors and one deep acceptor plus one deep donor-like centre. each of the three cases is discussed in correspondence with different experimental results.

International Nuclear Information System (INIS)

The effect of yttrium substitution at the lanthanum site on the superconducting properties of La_1_-_xY_xO_0_._9F_0_._1FeAs ('x' = 0, 0.10, 0.20, 0.30, 0.50 and 0.60) oxypnictides has been studied. Powder X-ray diffraction studies confirm single phases till x = 0.1 beyond which minor amount of Y_2O_3 is observed. The temperature dependence of resistivity measurements confirm the superconducting transition temperature (T_c) of 34.8 (#+-#0.05) K and corresponding Meissner transition at 34.3 K in the 'x' = 0.3 composition which is higher than that reported for the parent phase (LaO_0_._9F_0_._1FeAs (T_c = 28 K)). Further increase in the concentration of yttrium leads to broadening and suppression of the superconducting transition. The value of H_c_2 at zero temperature is estimated to be about 60.5 T. The Seebeck coefficient (S) shows a negative sign indicating that the major contribution to the conductivity is by electrons. The Hall coefficient (R_H) also remains ...

Science.gov (United States)

The galvanomagnetic properties of single-crystal samples of the Bi{sub 0.93}Sb{sub 0.07} semiconductor alloy with the electron density n = 1.6 x 10{sup 17} cm{sup -3} in magnetic fields up to 14 T at T = 1.6 K have been investigated. The resistivity {rho} and Hall coefficient R have been measured as functions of the magnetic field directed along the binary axis of a crystal for a current flowing through a sample along the bisector axis; i.e., the components {rho}{sub 22} and R{sub 32,1} have been measured. The strong anisotropy of the electron spectrum of the samples makes it possible to separately observe quantum oscillations of the magnetoresistance {rho}{sub 22}(H) for H -parallel C{sub 2} in low magnetic fields for two equivalent ellipsoids with small extremal cross sections (secondary ellipsoids) and in high magnetic fields for electrons of the ellipsoid with a large extremal cross section (main ellipsoid). An increase in the energy of the electrons of ...

CERN Document Server

The Influence Of Plasma Temperature On Wake Wave Generation

CERN Document Server

Lithography Production Techniques for next Generations of Microelectronics

British Library Electronic Table of Contents (United Kingdom)

Herein, we report engineering of nanostructured p-CuIn3Se5/n-CdS heterojunction thin film on a glass substrate, which is prepared at room temperature using simple wet chemical approach involving ion exchange reactions between CdS and Cu^+, In^3^+ and Se^2^- ions in alkaline medium. The uniform deposition of heterojunction thin films is achieved by optimizing the pH, temperature and molarity of the reactant bath. The as-deposited thin-films were annealed at 200^oC in air for 1h and further characterized for structural, optical and electrical properties using UV-Vis spectrophotometer, X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), Hall effect for type of conductivity, and I-V measurement to investigate the char...

International Nuclear Information System (INIS)

Reactive milling of NiO + Al powder mixture resulted in the formation of NiAl-Al_2O_3 nanocomposite powders, with a crystallite size of about 20 nm. The Hall-Williamson analysis revealed that NiAl showed an orientation dependent crystallite size after short processing time and orientation dependent internal strain after long milling time. Both anisotropies were removed by heating the powders in the differential scanning calorimetry. Calorimetric studies showed one exothermic effect attributed to the reduction reaction of NiO and endothermic one associated with melting of Al. Two methods were applied for powders compaction: resistance sintering and pulse electric discharge. In both cases the densities of abut 90% of the theoretical value were achieved. A significant increase in average NiAl crystallites size in compacted samples was observed, up to several hundreds of nanometers.(author)

Energy Technology Data Exchange (ETDEWEB)

The cost of transporting biogas digestate can be decreased by reducing its water content. However, the digestate emits volatile compounds during drying. This study investigated the drying behaviour and the change of digestate composition. Drying took place in a hybrid solar/waste-heat dryer that used solar energy as well as waste heat from a combined heat and power unit (CHP) and the exhaust air of a microturbine. The experiment involved the use of 60 t of liquid digestate. Climatic conditions were measured inside and outside the drying hall. Dry matter (DM) and organic dry matter (ODM) were also measured on a daily basis. In addition, the energy consumption of waste and solar heat were recorded and related to the quantity of dried feedstock. The total nitrogen, ammonium, phosphate, potassium oxide, magnesium oxide and calcium oxide in the digestate were subjected to chemical analysis before and after the drying process. Losses of nitrogen were calculated. Specific ...

CERN Multimedia

At the inauguration of the new CMS visitor centre. The CMS experiment inaugurated a new visitor centre at its Cessy site on 14 June. This will allow the thousands of people who come to CERN each year to follow the construction of one the Laboratory's flagship experiments first-hand. CERN receives over 20,000 visitors each year. Until recently, many of them were taken on a guided tour of one of the LEP experiments. With the closure of LEP, however, trips underground are no longer possible, and the Visits' Service has put in place a number of other itineraries (Bulletin 46/2000). Since the CMS detector will be almost entirely constructed in a surface hall, it is now taking a big share of the limelight. The CMS visitor centre has been built on a platform overlooking CMS construction. It contains a set of clear descriptive posters describing the experiment, along with a video projection showing animations and movies about CMS construction. In the coming weeks, a ...

CSIR Research Space (South Africa)

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Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

CERN Document Server

Complete intersection Calabi-Yau manifolds ; 2, three generation manifolds

International Nuclear Information System (INIS)

Design process of steam generator and condenser at Russian nuclear power plant type WWER-1000 is identified. The four chapter of the books are organized as nuclear power plant, types of steam generators specially horizontal steam generator, process of steam generator design and the description of condenser and its process design.

Science.gov (United States)

Analytical relations are obtained for estimating how the distributions of temperature and heat flux vary along a steam-generating tube and how the steam-generator power output reduces due to formation and accumulation of deposits.

UK PubMed Central (United Kingdom)

1. Nitric oxide generation is important in the regulation of resistance vessel tone. Until now, however, there has been no evidence of such a role for basal generation of nitric oxide in the skin microcirculation...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

Statistical data on experience gained from operation of steam generators around the world are presented, problems arising in vertical and horizontal steam generators are described, and the conditions of heattransfer tubes used in them are compared.

Science.gov (United States)

The general objective of the International Seminars of Horizontal Steam Generator Modelling has been the improvement in understanding of realistic thermal hydraulic behaviour of the generators when performing safety analyses for VVER reactors. The main to...

International Nuclear Information System (INIS)

The thermodynamic aspects of indium-face InN growth by radio frequency plasma-assisted molecular-beam epitaxy (rf-MBE) and the nucleation of InN on gallium-face GaN (0001) surface were investigated. The rates of InN decomposition and indium desorption from the surface were measured in situ using reflected high-energy electron diffraction and the rf-MBE 'growth window' of In-face InN (0001) was identified. It is shown that sustainable growth can be achieved only when the arrival rate of active nitrogen species on the surface is higher than the arrival rate of indium atoms. The maximum substrate temperature permitting InN growth as a function of the active nitrogen flux was determined. The growth mode of InN on Ga-face GaN (0001) surface was investigated by reflected high-energy electron diffraction and atomic force microscopy. It was found to be of the Volmer-Weber-type for substrate temperatures less than 350 deg. C and of the Stranski-Krastanov for substrate temperatures between 350 ...

International Nuclear Information System (INIS)

The thermal-hydraulic tests for a horizontal steam generator of a next-generation PWR (New PWR-21) were performed. The purpose of these tests is to understand the thermal-hydraulic behavior in the secondary side of horizontal steam generator during the plant normal operation. A test was carried out with cross section slice model simulated the straight tube region. In this paper, the results of the test is reported, and the effect of the horizontal steam generator internals on the thermal-hydraulic behavior of the secondary side and the circulation characteristics of the secondary side are discussed. (author).

CERN Document Server

We investigate the solar neutrino problem in the scenario of three generation neutrino oscillation hypothesis, taking into account other phenomenological constraints to the neutrino mixing and mass parameters.

International Nuclear Information System (INIS)

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

International Nuclear Information System (INIS)

This paper describes the construction of PWR horizontal steam generator in Soviet Union, the water chemistry treatment for secondary side, the design of steam separator, the test of heat transfer characteristics and operation. (author).

British Library Electronic Table of Contents (United Kingdom)

The results obtained from experimental investigations and mathematical simulation of horizontal steam generators are considered. Recommendations for continuing these works are given.

Energy Technology Data Exchange (ETDEWEB)

This paper presents a new method and newly developed stabilizing equipment to prevent the loss of synchronism of generators in pumped-storage plants from spreading. The proposed method includes functions to estimate the swing of each generator by using on-line generator output sampled at a rate of 600 times per second after an occurrence of disturbance such as fault, faulty equipment and so on, to predict generator swing 200-300 milliseconds ahead and loss of synchronism between generators in pumped-storage plants and those in thermal and nuclear plants, and to decide the number of generators that must be shed to maintain stability. Tokyo Electric Power Co. (TEPCO) installed the newly developed stabilizing equipment based on this method in the power system in June, 1986.

International Nuclear Information System (INIS)

Additional measurements have been made of deposition and retention of inhaled radioactively labeled iron oxide aerosols generated by a spinning top aerosol generator.

International Nuclear Information System (INIS)

This is the first volume in a series of books to be published by Prentice Hall on Environmental and Intelligent Manufacturing Systems. The editors have assembled an interdisciplinary collection of authors from industry, government, and academia, that provide a broad range of expertise on robotics and remote systems. Readily accessible to practicing engineers, the book provides case studies and introduces new technology applicable to remote operations in unstructured and/or hazardous environments. Chapter 1 gives an overview of the US Environmental Protection Agency's efforts to apply robotic technology to assist in the operations at hazardous waste sites. The next chapter focuses on the theory and implementation of robust impedance control for robotic manipulators. Chapter 3 presents a discussion on the integration of failure tolerance into robotic systems. The next two chapters address the issue of sensory feedback and its indispensable role in remote and/or ...

Energy Technology Data Exchange (ETDEWEB)

The production and characterisation of thin films made from molybdenum sulphide, molybdenum selenide, tungsten sulphide and tungsten selenide are described. The electronic properties of the thin films were examined by Hall measurements and by thermal sensors. For the MoSe[sub 2] films, the majority of the samples were n-conducting and p-conduction was only found for a few examples. All the other films (MoS[sub 2], WS[sub 2], WSe[sub 2]) were p-conducting. The electrical transport properties of the thin films are comparable to those of single crystals. With these thin films as absorber materials, it was possible for the first time to produce the polycrystalline solid n-ZnO/p-MoSe[sub 2], n-ZnO/WSe[sub 2], n-ZnO/WS[sub 2]- and n-ITO/WS[sub 2] solar cells. In spite of not yet optimized diode geometry (lateral build-up), a maximum short circuit current of I[sub SC] = 18 mA/cm[sup 2] was achieved for the MoSe[sub 2] diode. (orig.)

Energy Technology Data Exchange (ETDEWEB)

The paper reports on the results of a study of the synthesis conditions effects on magnetic and transport properties of nanosized layers of high-T{sub c} diluted magnetic semiconductors (DMS), such as Ge:Mn, Si:Mn and Si:Fe, fabricated by laser-plasma deposition over a wide range of the growth temperature, T{sub g}=(20-550) deg. C on single-crystal GaAs or Al{sub 2}O{sub 3} substrates. Ferromagnetism of the layers was detected by measurement data of the magneto-optical Kerr effect, anomalous Hall effect, negative magnetoresistance and ferromagnetic resonance (FMR) at 5-500 K. The optimum growth temperature, T{sub g}, for Si:Mn/GaAs layers with T{sub c}{approx}400 K is shown to be about 400 deg. C. The Si:Mn/Al{sub 2}O{sub 3} layers with 35% of Mn have the metal-type of conductivity with manifestation of magnetization up to room temperature. Different types of uniformly doped structures and digital alloys have been investigated. In contrast to GaSb:Mn films, ...

International Nuclear Information System (INIS)

The processes which are currently studied in the fabrication of B-doped ultra shallow junctions (USJ) usually involve a preamorphization step to reduce B channelling effect during implantation and to improve B electrical activation. At this stage a high amount of Si interstitial atoms (Is), which dramatically increases the B diffusivity, is introduced. The introduction of voids in Si is a promising tool to control B transient enhanced diffusion (TED), because of their ability to capture Is. In this work the efficiency of a cavity band to reduce B TED is checked in silicon interstitial supersaturation conditions, obtained by high dose Si implantation. He is implanted either at 10 keV or at 50 keV with a fluence of 5 x 10"1"6 cm"-"2. Conventional techniques to introduce and activate the B (conventional ion implantation and rapid thermal annealing (RTA)) are applied in order to have a better control of the technological process to focus on the benefit of the cavity layer. The samples were ...

International Nuclear Information System (INIS)

Horizontal steam generators are typical parts of nuclear power plants with pressure water reactor type VVER. By means of this computer program, a detailed thermal-hydraulic study of the horizontal steam generator PGV-1000 has been carried out and a special attention has been paid to the thermal-hydraulics of the secondary side. A set of important steam generator characteristics has been obtained and analyzed. Some of the interesting results of the analysis are presented in the paper. (author)

Science.gov (United States)

Not Available

International Nuclear Information System (INIS)

A survey was conducted of experience with steam generator tubes at nuclear power stations during 1976. Failures were reported at 25 out of 68 water-cooled reactors. The causes of these failures and the repair and inspection procedures designed to cope with them are summarized. Examination of the data indicates that corrosion was the major cause of steam generator tube failures. Improvements are needed in steam generator design, condenser integrity and secondary water chemistry control. (author).

International Nuclear Information System (INIS)

Short communication.

Energy Technology Data Exchange (ETDEWEB)

The presentation deals with the flows on the primary side of a horizontal steam generator under conditions typical to natural circulation cooling of the reactor. The main goal is to analyse the effect of primary flow patterns on the heat transfer capability of the steam generator. Conclusions pertinent to steam generator modelling with system codes are also drawn. (10 refs., 9 figs., 4 tabs.).

International Science & Technology Center (ISTC)

Photochromes for New Generation of Highly Efficient Computers with Three Dimensional (3D) Optical Memory

KoreaScience (Korea)

Full Text Available

Science.gov (United States)

Results are given of numerical simulation of three-dimensional pattern of flow of a two-phase steam-water mixture in the house of a PGV-1000 horizontal steam generator obtained using the BAGIRA best-estimate thermohydrodynamic computer codes. The space distributions of velocities and local void fractions in the steam generator housing for different modes of operation of power-generating unit are calculated and compared with available experimental data.

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Abstract Not Provided

International Nuclear Information System (INIS)

Superconducting generators for high power applications have been of interest for a number of years. Superconducting generators using low temperature superconductors (LTS) have been manufactured to produce up to 20 MW of electrical power and have been configured in either synchronous alternators which have an AC output that may be subsequently rectified to produce DC and homopolar generators which produce low voltage DC. Typically these generators require scrupulous attention to vacuum integrity for cryogenic insulation at 4.2K and tend to be somewhat fragile because of extensive thermal and magnetic shields that are not required in conventional power generators. Recently, high purity aluminum composites have been developed for a high power AC generator that is cooled by cryogenic hydrogen at 21K. This aluminum generator is very compact and ...

International Nuclear Information System (INIS)

... electric utilities electrochemistry energy storage fuel cells organizational models

Energy Technology Data Exchange (ETDEWEB)

This paper deals with dynamic study of co-generator system with derived dynamic models of generator, excitation system, and turbine/governor from field tests. Mainly this study concentrates on frequency control by under-frequency relay. We simulates dynamic study of co-generator system using EMTDC. (author). 4 refs., 13 figs., 4 tabs.

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Implementation of a plan to charge waste management costs to the facility that generates such waste requires a long-term commitment and consistent administration. The benefit is that generators are provided the incentive to optimize waste management practices if the charges are appropriately applied. This paper summarizes (1) a plan to charge waste generators, (2) the administrative structure of the plan, (3) a comparison between the rate structure and changes in waste disposal operations, and (4) issues that have surfaced as the plan is implemented. 2 refs., 1 fig., 1 tab.

British Library Electronic Table of Contents (United Kingdom)

Ways of improving the water chemistry used in the turbine generator stator?s cooling systems at Russian nuclear power plants are considered. Data obtained from operational chemical monitoring of indicators characterizing the quality of cooling water in the turbine generator stator cooling systems of operating power units at nuclear power plants are presented.

International Nuclear Information System (INIS)

The Steam Generator (SG) tubing degradation caused by corrosion and other age-related mechanisms continues to be a significant safety and cost concern for many Nuclear Power Plants (NPP). The understanding of the steam generator ageing mechanisms is the key to effective management of steam generator ageing and consists of the knowledge of steam generator materials and these one properties, stressors and operating conditions, like degradation sites and wear mechanisms. The principal types of corrosion are presented which can occur in CANDU steam generator. There are also presented the operation conditions, the specifications referring to the water chemistry and the construction materials of Steam Generator, the factors that have a great influence on the corrosion behaviour during the whole exploitation period of this equipment. (R.P.)

International Nuclear Information System (INIS)

This article describes the project for the installation of an additional emergency diesel generator in both Asco and Vandellos NPPs. The basic objectives of this project are to improve the availability of the emergency generation system, in order to provide greater ability to address potential contingencies, and also to increase the flexibility of the preventive periodic maintenance of the emergency diesel generators. This maintenance, that is currently a milestone of the critical path of the refueling outage, will be performed on-line. The new diesel generator will be sized to support all the loads considered in the safety case and also the consumption of its own auxiliary systems, and will be tested for operability assessment on the same periodical basis than the existing ones. The solution adopted will also permit that the N diesel generator may be connected to any bus bar class ...

Science.gov (United States)

The Stefan problem involving a source term is considered in this technical note. As an example, planar solidification with time-dependent heat generation in a semi-infinite plane is solved by use of a perturbation technique. The perturbation solution is validated by reducing the problem to the case without heat generation whose exact solution is available. An application to the case with constant heat generation is presented, for which a closed-form solution is obtained. The effects of heat generation and Stefan number on the evolution of solidification are examined using the perturbation solution.

International Nuclear Information System (INIS)

Purpose: In a case of automatically controlling the water level at the time of generating a lower power, to impact the followability of the control necessary for the power variation of the steam generator thereby to obtain good controllability. Constitution: A signal of deviation of water level of a steam generator and its set value and a signal of a difference between the temperature of the primary coolant in the high temperature side pipeline and that of the primary coolant in the low temperature side pipeline are used to automatically or manually control the flow quantity of water fed to the steam generator. (Yoshihara, H.).

Energy Technology Data Exchange (ETDEWEB)

This paper extends the analytical procedure described in another paper in these proceedings to analyze a variety of compact and light-weight OSC-designed radioisotope-heated generators. Those generators employed General Purpose Heat Source (GPHS) modules and a converter containing sixteen AMTEC cells of OSC`s revised five-tube design with enhanced cell wall reflectivity described in a companion paper in these proceedings. OSC found that the performance of the generator is primarily a function of the thermal insulation between the outside of the generator`s 16 cells and the inside of its wall. After examining a variety of insulation options, it was found that the generator`s performance is optimized by employing a hybrid insulation system, in which the space between the cells is filled with fibrous Min-K insulation, and the generator walls are lined with tapered ...

International Nuclear Information System (INIS)

The 3D modeling of the thermal hydraulic processes and soluble impurity distribution in the horizontal steam generator PGV-1000 was fulfilled with the thermal hydraulic code STEG. Steady-state operation of horizontal seam generator PGV-1000 was analyzed at nominal power. The modeling of the soluble impurity distribution was fulfilled on the basis of the previous thermal hydraulic modeling results. The processes of the soluble impurity deposition on the steam generator tube bundles and deposits outwash were considered in the mathematical model of the code. The modeling was fulfilled for horizontal steam generators with different peculiarities in construction. Calculation results were compared with experimental results obtained at NPP. The agreement between calculated and experimental results is quite reasonable. Results of modeling are sensible to the peculiarities of the horizontal steam ...

Energy Technology Data Exchange (ETDEWEB)

In an ignition timing control apparatus for controlling the ignition timing of each cylinder in order to reduce knock generation in a multi-cylinder engine, a lag-angle correction is made for the ignition timing of a cylinder in which a knock is generated and at the same time, a slight lag-angle correction is made for the ignition timing of the other cylinders in which no knock is generated. When the operating condition of engine is rapidly changed for example, under the condition in which knock is liable to occur in all cylinders as at rapid acceleration time, a lag-angle correction is made by the same amount as in the knock generating cylinder, for the ignition timing of cylinders in which no knock is generated. When no knock is generated for a predetermined time, a lead-angle correction is made for the ignition timing subjected to the lag-angle correction of ...

UK PubMed Central (United Kingdom)

We report a whole-genome shotgun assembly (called WGSA) of the human genome generated at Celera in 2001. The Celera-generated shotgun data set consisted of 27 million sequencing reads organized in pairs...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

A novel soft commutated direct current (DC) motor is introduced. The current of the commutated coil is intentionally drained before the brush disconnects the coil. This prevents the spark generation that normally occurs in conventional DC motors. A similar principle can be applied for DC generators.

Science.gov (United States)

The Second International Seminar on Horizontal Steam Generator Modelling was arranged to continue the international cooperation that was started during the first seminar in March 1991. The main topics of the seminar were: (1) further experimental results ...

International Nuclear Information System (INIS)

Processes and apparatus are disclosed for generation of radioisotope contaminant fission fragment free ozone from oxygen containing streams by chemonuclear irradiation accomplished by passing the stream past high energy radiation sources placed in sealed chambers.

Energy Technology Data Exchange (ETDEWEB)

A model was developed to compute concentration of impurities in the WWER 440 steam generator (SG) secondary water along the tube bundle. Calculated values were verified by concentration values obtained from secondary water sample chemical analysis. (orig.). 2 refs.

Energy Technology Data Exchange (ETDEWEB)

A submerged nuclear power station has been proposed as an alternative power station with a relatively low environmental impact for use by both industrialized and developing countries. The station would be placed 10 m above the seabed at a depth of 30--100 m and a distance of 10--30 km from shore. The submerged nuclear power station would be manufactured and refueled in a central facility, thus gaining the economies of factoryfabrication and the flexibility of short-lead-time deployment. To minimize the size of the submerged hull, horizontal steam generators are proposed for the primary-to-secondary heat transfer, instead of the more traditional vertical steam generators. The horizontal steam generators for SNPS would be similar in design to the horizontal steam generators used in the N-Reactors except the tube orientation is horizontal (the tube`s inlet and outlet connection points on the tubesheet are ...

International Nuclear Information System (INIS)

In this paper the authors show the means putting in place for examination of steam generators tubes. These means (eddy current probes, ultrasonic testing) associated with a knowledge on degradation phenomena allow mapping controlled tubes and limiting undesirable obturations.

British Library Electronic Table of Contents (United Kingdom)

Main results of the 40-year experience gained from operation of horizontal steam generators in VVER-type reactor installations used in Russia and many foreign countries are described. Existing unresolved problems are pointed out.

UK PubMed Central (United Kingdom)

PsychoPy is a software library written in Python, using OpenGL to generate very precise visual stimuli on standard personal computers. It is designed to allow the construction of as wide a variety of...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Electrical power is generated by steam turbines (steam being produced by coal, oil, gas or nuclear reactors), hydro units, gas turbines, internal combustion engines, jet engines, and pumped storage plants. Nuclear Power Plants generate only 15% of the total electrical power in the US. Nuclear Power Plants being cheaper to run are generally base loaded. The pumped-storage and gas turbine plants have ideal characteristics for peaking duty. In the pumping mode, pumped storage plants are used to provide additional system load and in the generating mode, they supply reactive power during peak load demands. Gas turbine plants have higher running costs, but are used as peaking units with a fast start capability. Fossil power plants need a minimum of 1 hour to stabilize expansion in the boiler and turbine generator. Due to a more competitive power supply market due to deregulation, most of the utilizes plan ...

UK PubMed Central (United Kingdom)

Generation of replicative defective viruses is frequently observed during viral infections. We now report that encapsidation and reverse transcription of spliced viral RNA is an additional mechanism...Full Text Available

Science.gov (United States)

This report discusses the work done on EPRI program S149-1. In this program the feasibility of cleaning steam generators off line with organic chelants as a means of arresting denting corrosion was investigated. The rationale behind this program is to mak...

International Nuclear Information System (INIS)

Steam generator tube plugging rates have increased markedly at Bruce since the end of the 1980s. A new programme of refurbishment aims to keep the steam generators operating successfully until around 2015. (Author).

International Nuclear Information System (INIS)

In this paper, we report on the analysis of reverse flow in inverted U-tubes of a steam generator under natural circulation condition. The mechanism of reverse flow in inverted U-tubes of the steam generator with natural circulation is graphically analyzed by using the full-range characteristic curve of parallel U-tubes. The mathematical model and numerical calculation method for analyzing the reverse flow in inverted U-tubes of the steam generator with natural circulation have been developed. The reverse flow in an inverted U-tube steam generator of a simulated pressurized water reactor with natural circulation in analyzed. Through the calculation, the mass flow rates of normal and reverse flows in individual U-tubes are obtained. The predicted sharp drop of the fluid temperature in the inlet plenum of the steam generator due to reverse flow agrees very well with the experimental ...

International Nuclear Information System (INIS)

The lateral bearing device is made of 7 lateral supports, each positioned to allow the displacement of the steam generator due to thermal or seismic effects. Each support includes a buffer plate that can be positioned on the steam generator using a position control assembly. This control assembly consists of a screw jack arrangement where the nut is fastened via an energy absorbing layer to a footplate that is fixed to the concrete wall of the steam generator enclosure. 4 figs.

CERN Document Server

We consider the impact of a 4th generation on Higgs to $\\gamma\\gamma$ and $WW,ZZ$ signals and demonstrate that the Tevatron and LHC have essentially eliminated the possibility of a 4th generation if the Higgs is SM-like and has mass below 200 GeV. We also show that the absence of enhanced Higgs signals in current data sets in the $\\gamma\\gamma$ and $WW,ZZ$ final states can strongly constrain (almost eliminate) the possibility of a 4th generation in two-Higgs-doublet models of type II (in the MSSM).

Energy Technology Data Exchange (ETDEWEB)

A method for cleaning timing optimization in a parallel steam generator system is described. The method is based on the minimization of a suitable objective function, and takes into account the load allocation on steam generators. In order to establish appropriate fouling growth models the mechanism of the particle deposition and removal on heat transfer surfaces is analyzed. The objective function is related to the short time management costs which are based on depreciation of steam generators, fuel costs and the costs of cleaning interventions. The optimization problem is described; a direct one level method is compared with a two level method. Some applications and their results are reported and discussed. (author)

International Nuclear Information System (INIS)

Adjusting generation to demand (load following) is compared with practical experience. The importance of pumped storage plants is emphasized.

International Nuclear Information System (INIS)

... Union (INTAS), Brussels (Belgium) Science and Technology Center in Unkraine,

Energy Technology Data Exchange (ETDEWEB)

Low cycle fatigue (LCF) of a fourth-generation single-crystal (SC) Ni-base superalloy TMS-138 was studied by comparison with a typical third-generation (TMS-75) and a second-generation (CMSX-4) Ni-base SC superalloys. TMS-138 exhibits improved LCF behaviour under a condition of the R ratio of 0 at temperatures of 1073 K and 1173 K. The addition of refractory elements resulted in a remarkable improvement of the LCF properties compared to those of the reference superalloys due to the different microstructure developed in TMS-138. (orig.)

Science.gov (United States)

... addition, the Department of Homeland Security works closely with The Combating Terrorism Technical Support Working Group (TSWG), to ensure ...

Science.gov (United States)

... in the design of such devices as fusion reactors, magnetohydrodynamic generators, magnetically levitated vehicles, magnetic forming devices, and ...

International Nuclear Information System (INIS)

... Industry, Material Science Research Laboratory, Yokosuka, Kanagawa (Japan)

Science.gov (United States)

... During operations, the system successfully treated Phosgene (CG), chloropicrin (PS), a smoke-generating formulation based on hexachloroethane ...

Science.gov (United States)

... Descriptors : *Combustible cartridge cases, *Polymers, *Test equipment, *Patents, Combustion chambers, Breech mechanisms, Gas generating ...

International Nuclear Information System (INIS)

... aluminium 28 building materials cockcroft-walton accelerators copper copper

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

The water and steam circuits of steam generators in pressurized-water nuclear power plants are described together with the mechanism of denting, and the corrosion of spacer plates that leads to cracks in tubes by constriction. The different chemical specifications applicable to the water of the secondary circuit of the generators in normal operation and on first commissioning are listed. The results obtained and the measurements of chemical values taken in operation on the water in the secondary circuits of steam generators at Fessenheim and Bugey are presented.

International Nuclear Information System (INIS)

Design considerations are given for the secondary side region of a vertical U-tube nuclear stream generator with an integral preheater. The thermal shield design, the novel recirculating water flow distribution scheme, the high porosity tube supports used in the parallel flow regions, and the U-bend supports are discussed for the Wolsung Plant steam generators. Experimental and analytical development programs undertaken to verify the design features are outlined.

International Nuclear Information System (INIS)

The nuclear power plants with WWER type reactors are characterized by horizontally situated steam generators (SG). During seismic event the horizontal and vertical ground accelerations induce fluid motion in directions of longitudinal and transversal axis. Resulting dynamic forces act on the SG attachment and could cause the failure of screws. In obvious PSA scenarios, these phenomena are classified as a indirect induced LOCA. In this paper the effects of transversal sloshing of fluid are analyzed.

International Nuclear Information System (INIS)

This paper dealt with the identification of possible damaging mechanism of the collector of the WWER 440 steam generator, cracking of primary collectors, corrosion damage of the protective coat of the primary collector circumferential weld, cracking of breathing space in the region of blinding effect by corrosion and strain, leaking of disassembling joint of the primary collector lid and with the integrity of heat exchanging tubes.

Energy Technology Data Exchange (ETDEWEB)

As a maintenance optimization project to improve the safety of Wolsung NPP (Nuclear Power Plant), reliability of diesel generators are estimated based on the operating experience, and improvement options are suggested. A reliability measure is suggested for the estimation of reliability for standby safety systems to reflect availability. It is assessed that the reliability of diesel generators can be mush improved if the suggested improvement options are implemented. (Author) 6 refs., 1 tab.

International Nuclear Information System (INIS)

The article applies the Probability Safety Assessment approach to analyze the risk impact of extension of allowed outage time of emergency diesel generator in Daya Bay NPP and adopts the risk-acceptance criteria used by NRC to evaluate changes to the licensing basis. The assessment results show that the risk impact is acceptable to increase the emergency diesel generator allowed outage time from 3 days to 14 days. (authors)

International Nuclear Information System (INIS)

Design layout of horizontal steam generator (SJ) with a special feedwater heating surface (by a surface water economizer), designated for NPPs with WWER-1000 reactors, is suggested. The design enables to decrease sharply the difference between the temperatures of saturation and feedwater. Blowdown outlet is organized against PG face, which increases the efficiency of flowing. The suggested layout enables to decrease thermal stresses in structural units and PG metal content, as compared to the PGV-1000 steam generator.

International Nuclear Information System (INIS)

We study the possibility of utilizing the superfluid to Mott-insulator quantum phase transition in an array of quantum well exciton-polariton traps to generate indistinguishable single photons in a massive parallel fashion. By means of analytical and numerical methods, the device operations and system properties are examined using realistic experimental parameters. Such a deterministic, massive parallel generation may find new applications in photonic quantum information processing.

International Nuclear Information System (INIS)

Plasma with a gas temperature below room temperature is not yet fully understood although it is expected to be an attractive tool for applications to material processing. In the present work, gas-temperature-dependent generation of a cryoplasma jet was studied. So far, we have generated a helium cryoplasma jet (296-5 K) under atmospheric pressure. At gas temperatures below 20 K, the helium excimer, He2, was observed clearly from by optical emission spectroscopy.

Energy Technology Data Exchange (ETDEWEB)

This document describes a simple and general way to generate House Simulation Protocol (HSP)-consistent internal sensible and latent loads in unoccupied homes. It is newly updated based on recent experience, and provides instructions on how to calculate and set up the operational profiles in unoccupied homes. The document is split into two sections: how to calculate the internal load magnitude and schedule, and then what tools and methods should be used to generate those internal loads to achieve research goals.

Energy Technology Data Exchange (ETDEWEB)

Statistical detail is given of the electricity generation and transmission systems in the UK. Breakdown by type of station, by fuel and the proportion generated by others apart from the generating or area boards is presented. Figures are provided for the various high voltage transmission lines in terms of route and circuit length as well as the number of towers and the capacity of mains transformers.

International Nuclear Information System (INIS)

This is a manuscript for a lecture contents: 1) Steam power and fundamentals of the steam power process, 3) conventional, nuclear and other steam generation processes, 4) cooling systems for steam power plants, 5) gas turbine power plants and combined-cycle power plants, 6) cogeneration, 7) development of thermal power plants and environmental effects. (GL).

Science.gov (United States)

This current awareness bulletin announces on a semimonthly basis the current worldwide information entered into the Energy Data Base on all aspects of direct energy conversion. Categories include photovoltaic conversion, magnetohydrodynamic generators, electrohydrodynamic generators, thermoelectric generators, thermionic converters, fuel cells, and miscellaneous converters. An abstract is inclluded with each citation. (WHK)

CERN Document Server

We present an approach to automatically generate interfaces supporting personalized interaction with digital libraries; these interfaces augment the user-DL dialog by empowering the user to (optionally) supply out-of-turn information during an interaction, flatten or restructure the dialog, and enquire about dialog options. Interfaces generated using this approach for CITIDEL are described.

Energy Technology Data Exchange (ETDEWEB)

This program is designed in order to calculate electricity generation cost by different energy sources, and menu type is adopted for user convenience. This program also graphically shows the share of capital investment cost, O and M cost, and fuel cost. Sensitivity analysis about discount rate can also be carried out by this program, taking into consideration the important role of the discount rate in the generation costs calculation. (Author) 7 refs., 1 fig., 3 tabs.

International Nuclear Information System (INIS)

A nonlinear mathematical model is presented of a WWER-440 nuclear power plant horizontal steam generator. On the proposed model is based a computer program for investigating transients in steam generators during loss of coolant accidents. Processes taking place at the primary side of the steam generator are described by a set of partial differential equations while those at the secondary side of the steam generator are described by plain differential equations with the variables being complex time functions. The model takes account of the coolant as both a single- and two-phase medium, of changes in the direction of the primary coolant flow and of changes in the direction of heat transfer. Heat transfer through the wall is based on a simple model of heat transfer through a thin-walled tube and includes a correction for the heat resistance of the wall. (author).

British Library Electronic Table of Contents (United Kingdom)

This paper uses multi-pass iteration particle swarm optimization (MIPSO) to solve short term hydroelectric generation scheduling of a power system with wind turbine generators. MIPSO is a new algorithm for solving nonlinear optimal scheduling problems. A new index called iteration best (IB) is incorporated into particle swarm optimization (PSO) to improve solution quality. The concept of multi-pass dynamic programming is applied to modify PSO further and improve computation efficiency.The feasible operational regions of the hydro units and pumped storage plants over the whole scheduling time range must be determined before applying MIPSO to the problem. Wind turbine power generation then shaves the power system load curves. Next, MIPSO calculates hydroelectric generation scheduling. It beg...

International Nuclear Information System (INIS)

This paper reviews generation methods of artificial earthquake motion and proposes an improved method of generating input motions for use in vibration tests of equipment to prove aseismic performance. The improved method employs beat wave repetition characteristic that inherently appears in the component waves of recorded earthquakes decomposed by bandpass filter and algebraic function phase for the component waves. Typical motions generated by the improved method satisfies prescribed severe conditions such as target response spectrum that are defined with a wideband frequency component and a limited maximum acceleration due to shaking table performance. The motions had never been generated by the conventional method.

Energy Technology Data Exchange (ETDEWEB)

Rice husk generated as a by-product of rice processing is an important energy resource. The availability of this resource in India has been assessed and the technologies for exploitation of its energy potential in the rice processing industry discussed. Nomographs have been developed for estimation of the husk required to meet the energy of parboiling, drying and milling operations. The unit cost of electricity using rice husk gasifier-based power generation systems has been calculated and its financial feasibility assessed in comparison with utility-supplied and diesel-generated electricity. With the cost and efficiency data assumed here, the unit cost of electricity produced by rice husk gasifier-dual fuel engine-generator system varies between Rs 2/kWh and Rs 7/kWh. (35 Rs approximates to SUS 1.). (author)

Energy Technology Data Exchange (ETDEWEB)

Since the first operation of nuclear steam generator early 1960s, its performance requirements have been met but the steam generator problems have been met but the steam generator problems have been major cause of reducing the operational reliability, plant safety and availability. U-tube assembly of steam generator forms the primary system pressure boundary of the plant and have experienced several types of tube degradation problems. Tube failure and leakage resulting from the degradation will cause radioactive contamination of secondary system by the primary coolant, and this may lead to unplanned plant outages and costly repair operations such as tube plugging or steam generator replacement. For the case of steam generators for heavy water reactors, e.g. Wolsong 2, 3, and 4 NPP, a high cost of heavy water will be imposed additionally. During the plant ...

Energy Technology Data Exchange (ETDEWEB)

Power system stabilizers (PSSs) are used to enhance damping of power system oscillations through excitation control of synchronous generator. The objective of the PSS is to generate a stabilizing signal, which produces a damping torque component on the generator shaft. Conventional PSSs are designed with the phase compensation technique in the frequency domain and include the lead-lag blocks whose parameters are determined according to a linearized power system model. The performance of conventional PSSs (CPSSs) depends upon the generator operating point and the system parameters, but a reasonable level of robustness can be achieved depending on the tuning method. This paper presents a new three-dimensional PSS (3D PSS), which uses rotor speed deviation, rotor acceleration and load angle deviation as input signals. The 3D PSS attempts to return the generator to the state-space ...

International Nuclear Information System (INIS)

Vertical U-tube steam generators in Pressurized Water Reactors (PWRs) operating an All Volatile Treatment (AVT) secondary chemistry have experienced corrosion problems, particularly denting and sludges. The studies reported evaluate the feasibility of using a low-concentration (0.5 wt%) chemical cleaning process to remove corrosion product deposits from steam generator surfaces and magnetite from tube-to-support plate crevices of PWR steam generators. The process potentially may be applied at schedule intervals, such as during normal refueling outages, to maintain a steam generator in clean operating condition. This report describes the results of testing to evaluate the effectiveness of several chelant acids for dissolving steam generator sludges and crevice magnetite. Corrosion of carbon steel by the chelant acids and the effects of various inhibitors are evaluated. The ...

International Nuclear Information System (INIS)

Construction of the French PWR nuclear program started in the early 70s, at the time a number of operating plants in the US were being affected by the first corrosion problems. Since, at that time, its construction program was in an early stage, FRAMATOME was able to make modifications on the first units to improve steam generator resistance to corrosion. For instance, full depth expansion of the tubes in the tube-sheet using an explosive process (Westex) was performed on Fessenheim 1 steam generators already installed on site. Later on, continuous operating experience was being obtained in the US, before startup of the French units. This allowed FRAMATOME to react rapidly and take immediate corrective actions at the design stage, during fabrication and sometimes even on site in order to mitigate the risk of corrosion in the steam generators. FRAMATOME is confident that the present design of its steam ...

International Nuclear Information System (INIS)

This project evaluated the feasibility of using a low-concentration (approx. 0.5 wt %) chemical cleaning process to remove corrosion product deposits from steam generator surfaces and magnetite from tube-to-support plate crevices of PWR steam generators. The primary objective was to develop a dilute process that could be safely applied at scheduled intervals, such as during normal refueling outages, to maintain a clean operating condition in the steam generator. The dilute chemical cleaning process developed in this project was demonstrated successfully on two model generators which were operated on faulted chemistry by DOE/CRC at Commonwealth's State Line Facility. Unit 5 was cleaned after 48 days of operation with 1% seawater fouling, and Unit 6 was cleaned after 112 days of operations with Lake Michigan water. This report describes work leading to the model generator cleaning ...

Energy Technology Data Exchange (ETDEWEB)

Nuclear Engineering Laboratory of the Technical Research Centre of Finland has widely used RELAP5/MOD2 and -MOD3 codes to simulate horizontal steam generators. Several models have been developed and successfully used in the VVER-safety analysis. Nevertheless, the models developed have included only rather few nodes in the steam generator secondary side. The secondary side has normally been divided into about 10 to 15 nodes. Since the secondary side at the steam generators of VVER-440 type reactors consists of a rather large water pool, these models were only roughly capable to predict secondary side flows. The paper describes an attempt to use RELAP5/MOD3 code to predict secondary side flows in a steam generator of a VVER-440 reactor. A 2D/3D model has been developed using RELAP5/MOD3 codes cross-flow junctions. The model includes 90 volumes on the steam generator secondary side. ...

International Nuclear Information System (INIS)

A calculation model was developed for the analysis of thermal and hydraulic processes in the PGV-1000 horizontal steam generator. The model makes it possible to examine the hydraulics of the primary medium, i.e., the distribution of flow velocities and mass flows in the exchanger tube system and hydraulic losses of the primary medium in the steam generator during its flow between the two connecting sites to the main circulation pipeline, spatial distribution of heat fluxes between the primary and secondary sides of the steam generator and the total transmitted thermal power, pressure on the secondary side of the generator, natural circulation of the working medium on the secondary side, and the mean circulation number, spatial distribution of the volume fraction of the steam component in the intertubular space, effect of the perforated sheet on the thermo-hydraulic processes in the steam ...

International Nuclear Information System (INIS)

The steam generator low water level trip setpoint of KORI NPP units 3 and 4(KNU 3 and 4), three-loop Westinghouse pressurized water reactor, is higher than that of OPR1000. In addition, steam generator downcomer water level in KNU 3 and 4 could fluctuate easily during a transient because of smaller downcomer water inventory, compared to the total water inventory in the steam generator. Due to these reasons, there is a higher possibility of unnecessary reactor trips caused by the steam generator low-low water level in KNU 3 and 4. Its operating history shows that most of reactor trips were caused by steam generator low-low level reactor trip signal. Such reactor trips, especially unnecessary ones, result in time and economic losses. In this paper, a feasibility study was performed to reduce unnecessary reactor trip by changing steam generator low-low water level ...

Energy Technology Data Exchange (ETDEWEB)

Different types of generators have been developed for the convenient use of {sup 99m}Tc as the demand for this radioisotope is strong. Currently, the demand for {sup 99m}Tc is more than 80 % of the total demand for medical isotopes in the world. A {sup 99m}Tc generator, in general, is composed of a column packed with ceramic adsorbent, tubing, eluent reservoir or vials, collection vials, and shielding. The key technology to develop a good generator is how to load {sup 99}Mo as much as possible while maintaining the quality of eluted {sup 99}mTc as good as possible. The technology is well developed and already available commercially for the case of the fission {sup 99}Mo/{sup 99}mTc because loading of few curries of {sup 99}Mo on a conventional adsorbent, i.e. alumina is not a serious task in the chemical point of view. However, the current infrastructure of the supply of {sup 99}Mo to the world market is sturdy as the ...

International Nuclear Information System (INIS)

Object: To control the average liquid level of each steam generator at a constant level irrespective of the flow rate of sodium thereby to decrease change in the retained amount of sodium and at the same time to improve the load response characteristic. Construction: A method for decreasing to as large an extent as possible a change in the amount of sodium retained in a steam generator due to change in the flow rate, which comprises the steps of detecting the main recirculating flow rate of liquid sodium by the use of a sodium flow rate detector, amplifying the detected flow rate signal depending upon the ratio between the flow rates respectively in a super-heater and a re-heater (distribution ratio), delivering the amplified signal to a function generator which generates a liquid level setting signal for maintaining the respective average liquid levels of the super-heater and the re-heater at constant ...

Energy Technology Data Exchange (ETDEWEB)

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

Energy Technology Data Exchange (ETDEWEB)

Relativistic electron beams are used for generating high power microwaves. These microwave sources require electron beam generators spanning significant ranges in voltage and impedance. The pulsed power technology used to generate these electron beams is presented. Electron beam generators that produce beams with pulse durations in the 10 ns to 100 ns regime consist of an energy storage section, pulse shaping section, and an electron beam diode. The energy storage section is either a Marx generator or capacitor bank-pulsed transformer. The pulse shaping is done with high-voltage transmission lines. The electron beam diode is usually a cold-cathode, space-charge-limited flow device. For longer pulses (approx.1 ..mu..s) the energy storage and pulse shaping can be combined. Lumped-element pulsed-forming networks (PFN) can be designed to produce the desired pulse shape. The Marx ...

International Nuclear Information System (INIS)

TVA is currently engaged in an extensive program to mitigate steam generator tube denting at the Sequoyah Nuclear Plant, which is in commercial operation, and to prevent or minimize the onset of denting at the Watts Bar Nuclear Plant, which is under construction. This paper describes TVA's denting mitigation program, which is primarily feedwater chemistry and system operation improvement, and the effect the changes that have been implemented have had on the incidence as well as the progression rate of steam generator tube denting during the past 220 effective full power days of Sequoyah unit 1 operation.

Energy Technology Data Exchange (ETDEWEB)

This report illustrates how, thanks to the development of a new algorithm for the probabilistic evaluation in a given period (e.g. one week) of the operating costs and risk indices (reliability) of a generation system with energy-constrained units, it has been possible to significantly improve the WAT program, used for many years by ENEL for generation expansion planning studies. In particular, it describes how the annual simulation of the system operation is accomplished, so as to calculate the mean expected values of the yearly operating costs (fuel) and the risk indices, at the same time optimizing the use of hydro resources and pumped-storage plants. (author).

CERN Document Server

In situ optical absorption spectroscopy was used to study the generation of E' centres in amorphous SiO_2 occurring by photo-induced breaking of Si-H groups under 4.7eV pulsed laser radiation. The dependence from laser intensity of the defect generation rate is consistent with a two-photon mechanism for Si-H rupture, while the growth and the saturation of the defects are conditioned by their concurrent annealing due to reaction with mobile hydrogen arising from the same precursor. A rate equation is proposed to model the kinetics of the defects and tested on experimental data.

Science.gov (United States)

Eight years ago, corrosion and tube denting seriously threatened the reliability and design life of steam generators, especially for closed loop arrangements in pressurized water reactors (PWRs). Concentrated research by the Steam Generator Owners Group (SGOG) diagnosed the causes and produced effective solutions, notably guidelines for water chemistry control in the secondary loop. The guidelines recommend specific levels of water impurities and remedial actions to prevent cooling-water leaks in the condenser, prevent air leaks, limit corrosion product buildup, and remove some impurities while neutralizing others. Continued research in SGOB-II is investigating intergranular corrosion and stress corrosion cracking. 3 figures.

Energy Technology Data Exchange (ETDEWEB)

All power plant engineers face the problem of peak power demands. Pumped storage plants are used to generate peak load power by pumping up water utilizing off-peak energy of hydrothermal and thermonuclear plants. This is the first accessible text/reference to cover hydroelectric power generation with emphasis on engineering to meet peak power demands by means of pumped storge plants, tidal power plants, and low head power generation. Text covers hydrology, mechanical and electrical equipment, accessories such as penstocks and valves, and civil engineering considerations. Contains descriptions of several existing plants. Includes 200 diagrams and 50 photographs.

Science.gov (United States)

This study presents a theoretical analysis of heat generation and dissipation of field-controllable magneto-rheological fluid (MRF) shock absorbers. Since MRF dampers are energy- dissipating devices, the issues of heat generation and dissipation are important in predicting their performance. A theoretical model is developed based on Bingham plastic model to estimate temperature history of the MRF dampers. The governing equation includes the MRF viscosity as a function of the temperature. The numerical solutions are compared with experimental results in order to validate the accuracy of the model, and excellent agreements are obtained.

Energy Technology Data Exchange (ETDEWEB)

Large scale steam storage power generation, one of the new energy storage systems for the future of inflexible electric power sources consisting of nuclear and coal power plants has been studied on the subjects of the systems to be attached to coal and nuclear power units, of the definition of storage efficiency and of the vertical steam storage vessel technology. Steam storage power generation may be hopeful for its higher efficiency similarly defined as of pumped storage plants while high temperature heat storage and the internal structure of large vertical steam storage vessel (accumulator) need to be developed.

Energy Technology Data Exchange (ETDEWEB)

A confocal microscopy imaging system was devised to selectively detect Second harmonic signals generated by biological tissues. Several types of biological tissues were examined using this imaging system, including human teeth, bovine blood vessels, and chicken skin. All these tissues generated strong second harmonic signals. There is considerable evidence that the source of these signals in tissue is collagen. Collagen, the predominant component of most tissues, is known to have second order nonlinear susceptibility. This technique may have diagnostic usefulness in pathophysiological conditions characterized by changes in collagen structure including malignant transformation of nevi, progression of diabetic complications, and abnormalities in wound healing.

International Nuclear Information System (INIS)

When analyzing the loss-of-coolant accidents at VVER reactor NPP the problem of the effect of noncondensable gases on heat transfer in a horizontal steam generator (HSG) is gaining in importance. Based on the RELAP5/MOD3.2 computer code one analyzed the experiments to condense steam-and-gas mixture in a HSG. The calculations are shown to predict satisfactorily duration of steam generator poisoning from noncondensable gas

Energy Technology Data Exchange (ETDEWEB)

This Fact Sheet presents the mission of the West Valley Demonstration Project and information on the 1994 pollution prevention and recycling accomplishments.

Science.gov (United States)

or third generation fuels. These are biofuels that can directly substitute for gasoline, jet fuel, and diesel. Today more than 9 billion gallons of biofuels are produced annually...

Energy Technology Data Exchange (ETDEWEB)

The lateral bearing device is made of 7 lateral supports, each positioned to allow the displacement of the steam generator due to thermal or seismic effects. Each support includes a buffer plate that can be positioned on the steam generator using a position control assembly. This control assembly consists of a screw jack arrangement where the nut is fastened via an energy absorbing layer to a footplate that is fixed to the concrete wall of the steam generator enclosure. 4 figs.

Energy Technology Data Exchange (ETDEWEB)

The removal of toxic metals and alkalis from gas streams at high temperatures was investigated. This is important for the development of coal-fired combined cycle power generation systems.

British Library Electronic Table of Contents (United Kingdom)

This paper describes the modeling of horizontal steam generator with the TRACE code and calculation results of a loss-of-feedwater (LOF-10) experiment at the PACTEL facility. Parallel Channel Test Loop (PACTEL) is an integral test facility for a VVER-440 type nuclear reactor. The main objectives were to prepare a simulation model for its horizontal steam generator with the TRACE thermal hydraulic code and assess different modeling options of the code. PACTEL experiment LOF-10 was chosen for this assessment. The calculation results showed that TRACE is capable in simulating horizontal steam generator behavior both in steady state and during loss-of-feedwater transient. The phenomenon of heat transfer from primary to secondary side, steam superheating and flow reversal in the lowest heat exc...

International Nuclear Information System (INIS)

Steam generators for nuclear plants require access to the primary and secondary side for various inspection, cleaning and repair procedures and upon achieving access various inspection and cleaning tasks must be carried out. Steam generators currently at manufacture are therefore provided with; primary side access via the primary manways, steam drum access via the steam drum manway, U-bend region access via the secondary manway and drum-internals access passages, tubesheet secondary side access via tubesheet level inspection ports and tube support plate access via tube support level access ports. Many CANDU steam generators were built with only primary and drum manways and either no tubesheet ports or ports which were located ineffectively. The steam generators at Wolsong 1 were built with secondary side inspection ports that provided only limited access away from the no-tube-lane. In addition they have ...

International Nuclear Information System (INIS)

The steam generator availability is one of the important problems encountered during the pressurized water nuclear plant operation. Various kinds of corrosion phenomena were observed in the past. These phenomena result from the concentration of impurities mainly in three locations in the steam generators: the tubesheet crevices, the tube support plate crevices, and the sludge pile. Corrections were made in the design and the materials used but a number of steam generators suffer or will suffer from corrosion processes inducing in many cases forcing their replacement. In order to prevent or to retard the corrosions several laboratories have performed experiments to reproduce and to study the corrosion processes. The first step of the degradation is the concentration of chemical species. A method using /sup 24/Na as a radioactive tracer was used to establish the concentration kinetics of caustic which was identified as the ...

International Nuclear Information System (INIS)

A reasonable understanding of PWR steam generator corrosion mechanisms such as denting and wastage has been developed, and adequate chemistry control programs defined to obviate the magnitude and effects of these modes of attack. However, relatively unique corrosion attack modes have been encountered at several plants notwithstanding the presence of a reasonable to very good chemistry control program when considered in light of the Steam Generator Owners Group chemistry guidelines. The uniqueness of attack also suggests that parameters not routinely measured or monitored may be playing a significant role. In the authors opinions, the only reasonable method of routinely identifying corrosion accelerating species present in crevices, sludge piles, and deposits in PWR steam generators is by performing detailed chemical return studies during power transients, shutdowns, and long term layups. Although it would be preferable to ...

International Nuclear Information System (INIS)

In order to improve the reliability of PWR steam generators, we have performed research to improve the tubing material and tube-support-plate configuration, based on our wide operating experience, and have developed and verified Alloy TT690 as the optimum tubing material and the BEC (Broached Egg Crate) type tube-support design. In the research, we have studied the metallurgical mechanism of the alloy to improve its corrosion resistance, evaluated corrosion susceptible region quantitatively, estimated the actual environment in a steam generator and confirmed the reliability by a model boiler test over a long period. It has been verified that the steam generator with the latest design has higher reliability with respect to the corrosion resistance of tubes. (author).

Science.gov (United States)

fuel obligation under the RFS2 program for the production or importation of conventional jet fuel, RINs can be generated for renewable jet fuel. Is that right? A: As described in...

International Nuclear Information System (INIS)

Russian 2009 p. 173-175 Russian Federation Rukhlyada, N.Ya. Chusov,

Science.gov (United States)

Defense satellites, including the next generation GPS and MILSTAR, continue to require TID well above that of most COTS silicon. ...

UK PubMed Central (United Kingdom)

In this paper, we suggest that perception could be modeled by assuming that sensory input is generated by a hierarchy of attractors in a dynamic system. We describe a mathematical model which exploits...Full Text Available

Science.gov (United States)

The kWh model finds the kWh outputs of each plant and reservoir capacities of hydro and pumped storage plants and minimizes the sum of fixed charges for constructing the reservoirs and generating facilities, also the fuel costs of thermal and nuclear plants. It is a linear programming problem whose constants are represented by nonlinear functions of kW running capacity of each plant. The optimal pattern of nuclear and thermal units is found by solving the linear programming problem derived for the pumped storage and hydroplants. Excluding the upper bound constraints, the number of constraint equations are few and do not increase with the number of units, although the number of variables increases. The computing time increases only in proportion to the number of groupings of generating units. Sensitivity analysis can be done easily. The detailed operational behavior of each generating unit can be taken into account.

British Library Electronic Table of Contents (United Kingdom)

A technology for removal of undissolved impurities from a horizontal steam generator using purge water is developed on the basis of a theoretical analysis. A purge with a maximal flow rate is drawn off from the zone with the highest accumulation of sludge in the lower part of the steam generator after the main circulation pump of the corresponding loop is shut off and the temperatures of the heat transfer medium at the inlet and outlet of the steam generator have equilibrated. An improved purge configuration is used for this technology; it employs shutoff and regulator valves, periodic purge lines separated by a cutoff fixture, and a D y 100 drain union as a connector for the periodic purge. Field tests show that the efficiency of this technology for sludge removal by purge water is severa...

Science.gov (United States)

Sep 1, 2011 ... Description: What amount of extra energy can be generated after subtracting the total energy consumed to produce the biomass energy? ...

Science.gov (United States)

Jun 4, 2004 ... On a two-year trip to Mars, according to one estimate, a crew of six humans will generate more than six tons of solid organic waste--much of ...

Science.gov (United States)

material may survive intact and mix back into interstellar gas clouds, helping to fuel the next generation of stars. NASA's Jet Propulsion Laboratory, Pasadena, Calif.,...

Energy Technology Data Exchange (ETDEWEB)

The kinetic energy transferred to some elements by an electron of kinetic energy 100 to 400 kV is discussed. The displacement rates are compared to the signal generation. (DCL)

Science.gov (United States)

Not Available

Science.gov (United States)

Mechanisms, AGARD Conference Proceedings No. 131, 1974, Paper No. 11. ... Olsen, W. and Karchmer, A., Lip Noise Generated by Flow Separation From Nozzle ...

International Nuclear Information System (INIS)

Results of calculational investigations into circulation of water and steam-and-water mixture in the PGV-1000 steam generator heat exchanger bundle used at NPPs with the WWER-1000 reactors, are considered. Model of water circulation in horizontal steam generator with submerged heating surface under conditions of steam generation irregularity along the heat transfer tubes is made. On the basis of the obtained data the assumption is made about water essential overflows from the hot collector zone into the cold one. Overflow rate over the upper line of the heat transfer tubes may constitute 0.7 m/s. The conclusion is made about the necessity to set up the vertical barrier which divides hot and cold sections of heat transfer tubes and helps to avoid water transverse overflows.

Energy Technology Data Exchange (ETDEWEB)

This paper deals with the heat transfer characteristics of horizontal steam generators, particularly under natural circulation (decay heat removal) conditions on the primary side. Special emphasis is on the inherent features of horizontal steam generator behaviour. A mathematical model of the horizontal steam generator primary side is developed and qualitative results are obtained analytically. A computer code, called HSG, is developed to solve the model numerically, and its predictions are compared with experimental data. The code is employed to obtain for VVER 440 steam generators quantitative results concerning the dependence of primary-to-secondary heat transfer efficiency on the primary side flow rate, temperature and secondary level. It turns out that the depletion of the secondary inventory leads to an inherent limitation of the decay energy removal in VVER steam generators. ...

International Nuclear Information System (INIS)

... Masatsune IHI Technology Service Co., Ltd., Yokohama, Kanagawa (Japan)

Energy Technology Data Exchange (ETDEWEB)

Experience with the identification and tuning of exciter constants for a generating unit as the Second Nuclear Power Plant of Taiwan Power Company is reported. Field test is first performed on the excitation system with the generator open-circuited. Since the field test results differ from the computer simulation results using manufacturer`s constants, the authors first modify the manufacturer`s constants based on their previous experience to reach a preliminary set of parameters for the excitation system. Then a hybrid nonlinear simulation-sensitivity matrix method is developed to further refine the excitation system parameters. The exciter constants are tuned in order to give better dynamic response before a power system stabilizer is applied to the generator. Field tests are then performed in order to compare the dynamic response of the generator without and with power system stabilizer.

British Library Electronic Table of Contents (United Kingdom)

The rational use of energy has become a priority for all industries in Brazil, mainly after the energy rationing in 2001. Methodologies to quantify and improve the performance of plants that consume and generate electricity and thermal energy are being used to reach this goal. Exergoeconomic analysis provides a complete diagnosis of a plant, both in exergetic and in monetary values. This study shows the methodology used to assess the power generation system of the Companhia Siderurgica Tubarao (CST). The current system is based on a regenerative Rankine cycle using two gases from steel production - blast furnace gas (BFG) and coke oven gas (COG) - to generate electric power and occasionally steam for the process. Use of the Theory of Exergetic Cost allowed determination of monetary and exe...

Energy Technology Data Exchange (ETDEWEB)

The Coal and Electric Data and Renewables Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy prepares the EPM. This publication provides monthly statistics at the State, Census division, and US levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. The EIA publishes statistics in the EPM on net generation by energy source; consumption, stocks, quantity, quality, and cost of fossil fuels; and capability of new generating units by company and plant. 68 tabs.

International Nuclear Information System (INIS)

The possible long-term effects of chronic radiation exposure have been studied. Rats were given tritiated drinking water (3 #mu#Ci/ml) before and during pregnancy and thereafter continuously through five generations. The brains were studied at 30 and 120 days postnatally. Significant decreases in weight and DNA and protein contents of specific parts of the brain were found, the most pronounced decreases being in the diencephalon. The decrease in protein content were more pronounced than the decreases in DNA content; the decreases were also more pronounced at 30 days than at 120 days, and more pronounced in the fith generation than in previous generations.

Energy Technology Data Exchange (ETDEWEB)

The major contents in this study are as follows : - long-term forecast to the year of 2040 is provided for nuclear electricity generating capacity by means of logistic curve fitting method. - the role of nuclear power in a national economy is analyzed in terms of environmental regulation. To do so, energy-economy linked model is developed. By using this model, the benefits from the introduction of nuclear power in Korea are estimated. Study on inter-industry economic activity for nuclear industry is carried out by means of an input-output analysis. Nuclear industry is examined in terms of inducement effect of production, of value-added, and of import. - economic analysis of nuclear power generation is performed especially taking into consideration wide variations of foreign currency exchange rate. The result is expressed in levelized generating costs. (author). 27 refs., 24 tabs., 44 figs

Energy Technology Data Exchange (ETDEWEB)

There is an ever increasing demand to perform flow simulations that incorporate the complete details of geometry as well as sophisticated flow physics. This has led to the development of numerical algorithms that can simulate the actual flow phenomena with greater fidelity. However, the success of these algorithms hinges on the grid that models the geometry. Grid generation methods for 2-D models have long existed and the general lack of complexity of the simpler 2-D models has not quite challenged the efforts in this area. However, demands for generating better 3-D geometric models for flow simulations involving complex geometries have completely changed the perspective of grid generation strategies. As a consequence, grid generation efforts have earned equal significance as that of numerical solver efforts.

Science.gov (United States)

Magnetic coil pressure wave generation for magnetic forming

Energy Technology Data Exchange (ETDEWEB)

A full analysis is shown in this paper for the cost of kWh generated from photovoltaic station located in Kuwait. By using a 21 years weather data for Kuwait, the yearly generated energy was found by proposing the PV station capacity with known panels tilt angle. The cost of kWh generated from PV station was compared with the kWh generated from conventional units in the country. A sensitivity analysis was done to some factors, capital cost per installed PV peak watt, discount rate, and operating peak hours, which affect the cost of kWh production from both PV and conventional units. If the PV station is proposed to be installed in Kuwait, the capital cost per PV installed peak watt must be less than today`s prices. (author)

International Nuclear Information System (INIS)

The objective of the C-E/EPRI project, ''Alternative Steam Generator Materials and Designs,'' was to evaluate the corrosion behavior of contemporary or alternative steam generator materials under prototypic design and secondary fault (high contaminant) water conditions. Two model steam generators built with various support materials and designs were tested under representative thermal and hydraulic conditions. One model operated under seawater faulted all-volatile treatment (AVT) secondary water chemistry conditions. The other model operated under acidified fresh water faulted AVT conditions. This presentation focuses on the tube support and tubesheet corrosion results obtained by destructive examination of both models.

UK PubMed Central (United Kingdom)

High-throughput genomic and proteomic technologies have generated a wealth of publicly available data on ageing. Easy access to these data, and their computational analysis, is of great importance in...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

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

Science.gov (United States)

... Thus initiation will be from the shock generated from the front surface of the pellet after traversing the inert packing. Exploding bridgewire detonator ...