Science.gov

Sample records for br2 reactor utilization

  1. Steady-State Thermal-Hydraulics Analyses for the Conversion of the BR2 Reactor to LEU

    SciTech Connect

    Licht, J. R.; Bergeron, A.; Dionne, B.; Van den Branden, G.; Kalcheva, S.; Sikik, E.; Koonen, E.

    2015-12-01

    BR2 is a research reactor used for radioisotope production and materials testing. It’s a tank-in-pool type reactor cooled by light water and moderated by beryllium and light water (Figure 1). The reactor core consists of a beryllium moderator forming a matrix of 79 hexagonal prisms in a hyperboloid configuration; each having a central bore that can contain a variety of different components such as a fuel assembly, a control or regulating rod, an experimental device, or a beryllium or aluminum plug. Based on a series of tests, the BR2 operation is currently limited to a maximum allowable heat flux of 470 W/cm2 to ensure fuel plate integrity during steady-state operation and after a loss-of-flow/loss-of-pressure accident.

  2. Optimization strategies for sustainable fuel cycle of the BR2 Reactor

    SciTech Connect

    Kalcheva, S.; Van Den Branden, G.; Koonen, E.

    2013-07-01

    The objective of the present study is to achieve a sustainable fuel cycle in a long term of reactor operation applying advanced in-core loading strategies. The optimization criteria concern mainly enhancement of nuclear safety by means of reactivity margins and minimization of the operational fuel cycle cost at a given (constant) power level and same or longer cycle length. An important goal is also to maintain the same or to improve the experimental performances. Current developments are focused on optimization of control rods localization; optimization of fresh and burnt fuel assemblies in-core distribution; optimization of azimuth and axial fuel burn up strategies, including fuel assembly rotating and flipping upside down. (authors)

  3. Oxidation mechanisms of CF2Br2 and CH2Br2 induced by air nonthermal plasma.

    PubMed

    Schiorlin, Milko; Marotta, Ester; Dal Molin, Marta; Paradisi, Cristina

    2013-01-01

    Oxidation mechanisms in air nonthermal plasma (NTP) at room temperature and atmospheric pressure were investigated in a corona reactor energized by +dc, -dc, or +pulsed high voltage.. The two bromomethanes CF(2)Br(2) and CH(2)Br(2) were chosen as model organic pollutants because of their very different reactivities with OH radicals. Thus, they served as useful mechanistic probes: they respond differently to the presence of humidity in the air and give different products. By FT-IR analysis of the postdischarge gas the following products were detected and quantified: CO(2) and CO in the case of CH(2)Br(2), CO(2) and F(2)C ═ O in the case of CF(2)Br(2). F(2)C ═ O is a long-lived oxidation intermediate due to its low reactivity with atmospheric radicals. It is however removed from the NTP processed gas by passage through a water scrubber resulting in hydrolysis to CO(2) and HF. Other noncarbon containing products of the discharge were also monitored by FT-IR analysis, including HNO(3) and N(2)O. Ozone, an important product of air NTP, was never detected in experiments with CF(2)Br(2) and CH(2)Br(2) because of the highly efficient ozone depleting cycles catalyzed by BrOx species formed from the bromomethanes. It is concluded that, regardless of the type of corona applied, CF(2)Br(2) reacts in air NTP via a common intermediate, the CF(2)Br radical. The possible reactions leading to this radical are discussed, including, for -dc activation, charge exchange with O(2)(-), a species detected by APCI mass spectrometry. PMID:23190335

  4. European utilities requirements for future reactors

    SciTech Connect

    Roch, M.

    1996-12-31

    The prospect for future nuclear power plants has led the utilities of seven European countries to launch an effort to define the requirements that should be common to all utilities for the next reactors to be built in Europe. These requirements will ultimately be part of a four-volume document and will cover all aspects of a plant: performance, grid connection, codes and standards, materials, quality assurance, cost, and, of course, safety. The seven European countries - France, the United Kingdom, Germany, Spain, Italy, the Netherlands, and Belgium - issued revision A of Vols 1 and 2 in Nov. 1994, which deal with all the general requirements, not specific to any design, originally issued in March 1994. Comments were requested from most of the nuclear utilities as well as from reactor vendors worldwide. This gave rise to an enormous number of comments, which were duly considered by the European Union. The relevant ones were incorporated into revision B of Vols. 1 and 2, which was issued in Nov 1995, the objective of this revision B being essentially to gain approval from the safety authorities. A particular aspect of the European approach resides in the fact that these European requirements will have to be discussed and agreed on by at least nine safety authorities, i.e., the authorities of the seven counties that launched revision B, plus the authorities of two newcomers, Finland and Sweden, which have just applied for European Union membership.

  5. Utility guidelines for reactor noise analysis: Final report

    SciTech Connect

    Sweeney, F.J.

    1987-02-01

    Noise analysis techniques have been extensively utilized to monitor the health and performance of nuclear power plant systems. However, few utilities have adequate programs to effectively utilize these techniques. These programs usually provide low-quality data, which can lead to misinterpretation and false alarms. The objective of this work is to provide utilities and noise analysts with guidelines for data acquisition, data analysis, and interpretation of noise analysis results for surveillance and diagnosis of reactor systems.

  6. Increasing Fuel Utilization of Breed and Burn Reactors

    NASA Astrophysics Data System (ADS)

    Di Sanzo, Christian Diego

    Breed and Burn reactors (B&B), also referred to Traveling Wave Reactors, are fast spectrum reactors that can be fed indefinitely with depleted uranium only, once criticality is achieved without the need for fuel reprocessing. Radiation damage to the fuel cladding limits the fuel utilization of B&B reactors to ˜ 18-20% FIMA (Fissions of Initial Metal Atoms) -- the minimum burnup required for sustaining the B&B mode of operation. The fuel discharged from this type of cores contain ˜ 10% fissile plutonium. Such a high plutonium content poses environmental and proliferation concerns, but makes it possible to utilize the fuel for further energy production. The objectives of the research reported in this dissertation are to analyze the fuel cycle of B&B reactors and study new strategies to extend the fuel utilization beyond ˜ 18-20% FIMA. First, the B&B reactor physics is examined while recycling the fuel every 20% FIMA via a limited separation processing, using either the melt refining or AIROX dry processes. It was found that the maximum attainable burnup varies from 54% to 58% FIMA -- depending on the recycling process and on the fraction of neutrons lost via leakage and reactivity control. In Chapter 3 the discharge fuel characteristics of B&B reactors operating at 20% FIMA and 55% FIMA is analyzed and compared. It is found that the 20% FIMA reactor discharges a fuel with about ˜ 80% fissile plutonium over total plutonium content. Subsequently a new strategy of minimal reconditioning, called double cladding is proposed to extend the fuel utilization in specifically designed second-tier reactors. It is found that with this strategy it is possible to increase fuel utilization to 30% in a sodium fast reactor and up to 40% when a subcritical B&B core is driven by an accelerator-driven spallation neutron source. Lastly, a fuel cycle using Pressurized Water Reactors (PWR) to reduce the plutonium content of discharged B&B reactors is analyzed. It was found that it is

  7. Plutonium and minor actinides utilization in Thorium molten salt reactor

    SciTech Connect

    Waris, Abdul; Aji, Indarta K.; Novitrian,; Kurniadi, Rizal; Su'ud, Zaki

    2012-06-06

    FUJI-12 reactor is one of MSR systems that proposed by Japan. The original FUJI-12 design considers Th/{sup 233}U or Th/Pu as main fuel. In accordance with the currently suggestion to stay away from the separation of Pu and minor actinides (MA), in this study we evaluated the utilization of Pu and MA in FUJI-12. The reactor grade Pu was employed in the present study as a small effort of supporting THORIMS-NES scenario. The result shows that the reactor can achieve its criticality with the Pu and MA composition in the fuel of 5.96% or more.

  8. Plutonium and minor actinides utilization in Thorium molten salt reactor

    NASA Astrophysics Data System (ADS)

    Waris, Abdul; Aji, Indarta K.; Novitrian, Kurniadi, Rizal; Su'ud, Zaki

    2012-06-01

    FUJI-12 reactor is one of MSR systems that proposed by Japan. The original FUJI-12 design considers Th/233U or Th/Pu as main fuel. In accordance with the currently suggestion to stay away from the separation of Pu and minor actinides (MA), in this study we evaluated the utilization of Pu and MA in FUJI-12. The reactor grade Pu was employed in the present study as a small effort of supporting THORIMS-NES scenario. The result shows that the reactor can achieve its criticality with the Pu & MA composition in the fuel of 5.96% or more.

  9. Retrofittable Modifications to Pressurized Water Reactors for Improved Resource Utilization

    SciTech Connect

    1980-10-01

    This report summarizes work performed for the U.S. Arms Control and Disarmament Agency under BOA AC9NX707 (Task Order 80-02), as part of the Agency's continuing program on improved fuel utilization in light water reactors. The objective of the study was to investigate improvements in fuel management and design of water reactors (PWRs) that could potentially increase the utilization of natural uranium resources in a once-through fuel cycle (i.e., without using spent fuel reprocessing and recycle). For the present study, potential improvements were limited to retrofittable concepts, i.e., those which could be modifications to the reactor system or balance of plant. The potential improvements considered were not necessarily restricted to those which might be economical under current uranium ore prices or to those which might be acceptable to the nuclear industry at the present time. A six-month fuel cycle, for example, although technically possible, would be neither economical nor accept able to the industry at the present time. Although all potential improvements are not necessarily compatible with each other, the target objective was to seek a composite system of compatible improvements that, if possible, could increase uranium resource utilization by 30% or more. Economic factors, risks involved in the introduction, and potential licensing concerns are also addressed in the report.

  10. Analysis of the nuclear measurement program for an optimized BR2 core configuration

    SciTech Connect

    Van Den Branden, G.; Kalcheva, S.; Sikik, E.; Koonen, E.

    2013-07-01

    This paper presents the analysis of the results of the Nuclear Measurement Program (NMP) executed during the shut-down of cycle 05/2012 of the BR2 reactor. The aim of the NMP was to determine the properties of a reactor core load with a new configuration of the control rods and to evaluate/verify the predicted numerical results by MCNPX. The methods used for the interpretation of the measurement results include combinations of an analytical method for determination of the axial relative control rod efficiency and least square techniques. (authors)

  11. UWTOR-M, a stellarator power reactor utilizing modular coils

    NASA Astrophysics Data System (ADS)

    Sviatoslavsky, I. N.; Vansciver, S. W.; Kulcinski, G. I.

    1981-10-01

    The parametric considerations which led to the UWTOR-M reference design point are described. The design has 18 twisted coils utilizing a multipolarity of 3, a major radius of 24 m, a coil radius of 4.77 m and a plasma aspect ratio of 14. An assumed (ALPHA) of 5% was used. This configuration leads to a rotational transform on the edge of 1.125 giving favorable plasma physics conditions. The natural stellarator divertor is used for impurity control in conjunction with innovative high performance divertor targets. A unique blanket design which minimizes tritium inventory in the reactor is proposed. A scheme for servicing the first wall/blanket and other reactor components is described.

  12. Advanced Nuclear Technology: Advanced Light Water Reactors Utility Requirements Document Small Modular Reactors Inclusion Summary

    SciTech Connect

    Loflin, Leonard; McRimmon, Beth

    2014-12-18

    This report summarizes a project by EPRI to include requirements for small modular light water reactors (smLWR) into the EPRI Utility Requirements Document (URD) for Advanced Light Water Reactors. The project was jointly funded by EPRI and the U.S. Department of Energy (DOE). The report covers the scope and content of the URD, the process used to revise the URD to include smLWR requirements, a summary of the major changes to the URD to include smLWR, and how to use the URD as revised to achieve value on new plant projects.

  13. Zn2(TeO3)Br2

    PubMed Central

    Zhang, Dong; Johnsson, Mats

    2008-01-01

    Single crystals of dizinc tellurium dibromide trioxide, Zn2(TeO3)Br2, were synthesized via a transport reaction in sealed evacuated silica tubes. The compound has a layered crystal structure in which the building units are [ZnO4Br] distorted square pyramids, [ZnO2Br2] distorted tetra­hedra, and [TeO3 E] tetra­hedra (E being the 5s 2 lone pair of Te4+) joined through sharing of edges and corners to form layers of no net charge. Bromine atoms and tellurium lone pairs protrude from the surfaces of each layer towards adjacent layers. This new compound Zn2(TeO3)Br2 is isostructural with the synthetic compounds Zn2(TeO3)Cl2, CuZn(TeO3)2, Co2(TeO3)Br2 and the mineral sophiite, Zn2(SeO3)Cl2. PMID:21202162

  14. Lifetime studies in H2/Br2 fuel cells

    NASA Astrophysics Data System (ADS)

    Barna, G. G.; Frank, S. N.; Teherani, T. H.; Weedon, L. D.

    1984-09-01

    A fully computerized system has been set up for the life testing of H2 electrodes in 48 percent HBr, and of H2/Br2 fuel cells. Given a fuel cell design with dry H2 and no anolyte loop, the prime parameters influencing the operating lifetime are the hydrophobicity of the anode and the electrolyte transport property of the membrane. A systematic optimization of all the parameters has generated fuel cells that have operated for 10,000h at 2 A/sq in., with no significant degradation.

  15. Matrix isolation and computational study of isodifluorodibromomethane (F2CBr-Br): A route to Br2 formation in CF2Br2 photolysis

    NASA Astrophysics Data System (ADS)

    George, Lisa; Kalume, Aimable; El-Khoury, Patrick Z.; Tarnovsky, Alexander; Reid, Scott A.

    2010-02-01

    The photolysis products of dibromodifluoromethane (CF2Br2) were characterized by matrix isolation infrared and UV/Visible spectroscopy, supported by ab initio calculations. Photolysis at wavelengths of 240 and 266 nm of CF2Br2:Ar samples (˜1:5000) held at ˜5 K yielded iso-CF2Br2 (F2CBrBr), a weakly bound isomer of CF2Br2, which is characterized here for the first time. The observed infrared and UV/Visible absorptions of iso-CF2Br2 are in excellent agreement with computational predictions at the B3LYP/aug-cc-pVTZ level. Single point energy calculations at the CCSD(T)/aug-cc-pVDZ level on the B3LYP optimized geometries suggest that the isoform is a minimum on the CF2Br2 potential energy surface, lying some 55 kcal/mol above the CF2Br2 ground state. The energies of various stationary points on the CF2Br2 potential energy surface were characterized computationally; taken with our experimental results, these show that iso-CF2Br2 is an intermediate in the Br+CF2Br→CF2+Br2 reaction. The photochemistry of the isoform was also investigated; excitation into the intense 359 nm absorption band resulted in isomerization to CF2Br2. Our results are discussed in view of the rich literature on the gas-phase photochemistry of CF2Br2, particularly with respect to the existence of a roaming atom pathway leading to molecular products.

  16. Nuclear waste disposal utilizing a gaseous core reactor

    NASA Technical Reports Server (NTRS)

    Paternoster, R. R.

    1975-01-01

    The feasibility of a gaseous core nuclear reactor designed to produce power to also reduce the national inventories of long-lived reactor waste products through nuclear transmutation was examined. Neutron-induced transmutation of radioactive wastes is shown to be an effective means of shortening the apparent half life.

  17. Spent fuel utilization in a compact traveling wave reactor

    SciTech Connect

    Hartanto, Donny; Kim, Yonghee

    2012-06-06

    In recent years, several innovative designs of nuclear reactors are proposed. One of them is Traveling Wave Reactor (TWR). The unique characteristic of a TWR is the capability of breeding its own fuel in the reactor. The reactor is fueled by mostly depleted, natural uranium or spent nuclear fuel and a small amount of enriched uranium to initiate the fission process. Later on in the core, the reactor gradually converts the non-fissile material into the fissile in a process like a traveling wave. In this work, a TWR with spent nuclear fuel blanket was studied. Several parameters such as reactivity coefficients, delayed neutron fraction, prompt neutron generation lifetime, and fission power, were analyzed. The discharge burnup composition was also analyzed. The calculation is performed by a continuous energy Monte Carlo code McCARD.

  18. Matrix Isolation and Computational Study of iso-CF2Br2: a Route to Molecular Products in CF2Br2 Photolysis

    NASA Astrophysics Data System (ADS)

    George, Lisa; Kalume, Aimable; Reid, Scott A.; El-Khoury, Patrick Z.; Tarnovsky, Alexander

    2010-06-01

    The photolysis products of dibromodifluoromethane following selected wavelength laser irradiation were characterized by matrix isolation infrared and UV/Visible spectroscopy, supported by ab initio calculations. Photolysis at wavelengths of 240 and 266 nm of CF2Br2:Ar samples (1:5000) held at 5 K yielded iso-CF2Br2 (F2CBrBr), a weakly bound isomer of CF2Br2, which is characterized here for the first time. The observed infrared and UV/Visible absorptions of iso-CF2Br2 are in excellent agreement with computational predictions at the B3LYP/aug-cc-pVTZ level. Single point energy calculations at the CCSD(T)/aug-cc-pVDZ level on the B3LYP optimized geometries show that the iso-form is a minimum on the CF2Br2 potential energy surface, lying some 55 kcal/mol above the CF2Br2 ground state. The energies of various stationary points on the CF2Br2 PES were characterized computationally; taken with our experimental results, these show that iso-CF2Br2 is an intermediate in the Br + CF2Br reaction leading to molecular products (CF2 + Br2). The photochemistry of the iso-form was also investigated; excitation into the intense 359 nm absorption band resulted in isomerization to CF2Br2. Our results are discussed in view of the rich literature on the gas-phase photochemistry of CF2Br2, particularly with respect to the existence of a roaming atom pathway leading to molecular products.

  19. Reactor technology assessment and selection utilizing systems engineering approach

    SciTech Connect

    Zolkaffly, Muhammed Zulfakar; Han, Ki-In

    2014-02-12

    The first Nuclear power plant (NPP) deployment in a country is a complex process that needs to consider technical, economic and financial aspects along with other aspects like public acceptance. Increased interest in the deployment of new NPPs, both among newcomer countries and those with expanding programs, necessitates the selection of reactor technology among commercially available technologies. This paper reviews the Systems Decision Process (SDP) of Systems Engineering and applies it in selecting the most appropriate reactor technology for the deployment in Malaysia. The integrated qualitative and quantitative analyses employed in the SDP are explored to perform reactor technology assessment and to select the most feasible technology whose design has also to comply with the IAEA standard requirements and other relevant requirements that have been established in this study. A quick Malaysian case study result suggests that the country reside with PWR (pressurized water reactor) technologies with more detailed study to be performed in the future for the selection of the most appropriate reactor technology for Malaysia. The demonstrated technology assessment also proposes an alternative method to systematically and quantitatively select the most appropriate reactor technology.

  20. Reactor technology assessment and selection utilizing systems engineering approach

    NASA Astrophysics Data System (ADS)

    Zolkaffly, Muhammed Zulfakar; Han, Ki-In

    2014-02-01

    The first Nuclear power plant (NPP) deployment in a country is a complex process that needs to consider technical, economic and financial aspects along with other aspects like public acceptance. Increased interest in the deployment of new NPPs, both among newcomer countries and those with expanding programs, necessitates the selection of reactor technology among commercially available technologies. This paper reviews the Systems Decision Process (SDP) of Systems Engineering and applies it in selecting the most appropriate reactor technology for the deployment in Malaysia. The integrated qualitative and quantitative analyses employed in the SDP are explored to perform reactor technology assessment and to select the most feasible technology whose design has also to comply with the IAEA standard requirements and other relevant requirements that have been established in this study. A quick Malaysian case study result suggests that the country reside with PWR (pressurized water reactor) technologies with more detailed study to be performed in the future for the selection of the most appropriate reactor technology for Malaysia. The demonstrated technology assessment also proposes an alternative method to systematically and quantitatively select the most appropriate reactor technology.

  1. Liquid fuel molten salt reactors for thorium utilization

    DOE PAGESBeta

    Gehin, Jess C.; Powers, Jeffrey J.

    2016-04-08

    Molten salt reactors (MSRs) represent a class of reactors that use liquid salt, usually fluoride- or chloride-based, as either a coolant with a solid fuel (such as fluoride salt-cooled high temperature reactors) or as a combined coolant and fuel with fuel dissolved in a carrier salt. For liquid-fuelled MSRs, the salt can be processed online or in a batch mode to allow for removal of fission products as well as introduction of fissile fuel and fertile materials during reactor operation. The MSR is most commonly associated with the 233U/thorium fuel cycle, as the nuclear properties of 233U combined with themore » online removal of parasitic absorbers allow for the ability to design a thermal-spectrum breeder reactor; however, MSR concepts have been developed using all neutron energy spectra (thermal, intermediate, fast, and mixed-spectrum zoned concepts) and with a variety of fuels including uranium, thorium, plutonium, and minor actinides. Early MSR work was supported by a significant research and development (R&D) program that resulted in two experimental systems operating at ORNL in the 1960s, the Aircraft Reactor Experiment and the Molten Salt Reactor Experiment. Subsequent design studies in the 1970s focusing on thermal-spectrum thorium-fueled systems established reference concepts for two major design variants: (1) a molten salt breeder reactor (MSBR), with multiple configurations that could breed additional fissile material or maintain self-sustaining operation; and (2) a denatured molten salt reactor (DMSR) with enhanced proliferation-resistance. T MSRs has been selected as one of six most promising Generation IV systems and development activities have been seen in fast-spectrum MSRs, waste-burning MSRs, MSRs fueled with low-enriched uranium (LEU), as well as more traditional thorium fuel cycle-based MSRs. This study provides an historical background of MSR R&D efforts, surveys and summarizes many of the recent development, and provides analysis comparing

  2. 87. ARAIII. GCRE reactor building (ARA608) Mechanical equipment room. Utility ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    87. ARA-III. GCRE reactor building (ARA-608) Mechanical equipment room. Utility air receiver, dryer, and compressor sit on their foundations prior to grouting. December 22, 1958. Ineel photo no. 58-6429. Photographer: Ken Mansfield. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

  3. Optimized Battery-Type Reactor Primary System Design Utilizing Lead

    SciTech Connect

    Yu, Yong H.; Son, Hyoung M.; Lee, Il S.; Suh, Kune Y.

    2006-07-01

    A number of small and medium size reactors are being developed worldwide as well as large electricity generation reactors for co-generation, district heating or desalination. The Seoul National University has started to develop 23 MWth BORIS (Battery Optimized Reactor Integral System) as a multi-purpose reactor. BORIS is an integral-type optimized fast reactor with an ultra long life core. BORIS is being designed to meet the Generation IV nuclear energy system goals of sustainability, safety, reliability and economics. Major features of BORIS include 20 consecutive years of operation without refueling; elimination of an intermediate heat transport loop and main coolant pump; open core without individual subassemblies; inherent negative reactivity feedback; and inherent load following capability. Its one mission is to provide incremental electricity generation to match the needs of developing nations and especially remote communities without major electrical grid connections. BORIS consists of a reactor module, heat exchanger, coolant module, guard vessel, reactor vessel auxiliary cooling system (RVACS), secondary system, containment and the seismic isolation. BORIS is designed to generate 10 MWe with the resulting thermal efficiency of 45 %. BORIS uses lead as the primary system coolant because of the inherent safety of the material. BORIS is coupled with a supercritical carbon dioxide Brayton cycle as the secondary system to gain a high cycle efficiency in the range of 45 %. The reference core consists of 757 fuel rods without assembly with an active core height of 0.8 m. The BORIS core consists of single enrichment zone composed of a Pu-MA (minor actinides)-U-N fuel and a ferritic-martensitic stainless steel clad. This study is intended to set up appropriate reactor vessel geometry by performing thermal hydraulic analysis on RVACS using computational fluid dynamics codes; to examine the liquid metal coolant behavior along the subchannels; to find out whether the

  4. NEUTRON REACTOR FUEL ELEMENT UTILIZING ZIRCONIUM-BASE ALLOYS

    DOEpatents

    Saller, H.A.; Keeler, J.R.; Szumachowski, E.R.

    1957-11-12

    This patent relates to clad fuel elements for use in neutronic reactors and is drawn to such a fuel element which consists of a core of fissionable material, comprised of an alloy of zirconium and U/sup 235/ enriched uranium, encased in a jacket of a binary zirconium-tin alloy in which the tin content ranges between 1 and 15% by weight.

  5. Bell column downtube, reactors utilizing same and related methods

    SciTech Connect

    Turner, Terry D.; Bingham, Dennis N.; Benefiel, Bradley C.; Klinger, Kerry M.; Wilding, Bruce M.

    2015-12-22

    Reactors for carrying out a chemical reaction, as well as related components, systems and methods are provided. In accordance with one embodiment, a reactor is provided that includes a furnace and a crucible positioned for heating by the furnace. A downtube is disposed at least partially within the interior crucible along an axis. At least one structure is coupled with the downtube and extends substantially across the cross-sectional area of the interior volume taken in a direction substantially perpendicular to the axis. A plurality of holes is formed in the structure enabling fluid flow therethrough. The structure coupled with the downtube may include a lower body portion and an upper body portion coupled with the lower body portion, wherein the plurality of holes is formed in the lower body portion adjacent to, and radially outward from, a periphery of the upper body portion.

  6. Self-Trapped Excitons in Orthorhombic SnBr2

    NASA Astrophysics Data System (ADS)

    Yamasaki, Y.; Ohno, N.

    2001-08-01

    Luminescence properties of SnBr2 have been studied to reveal the photo-excited exciton relaxation process. Two types of luminescence with large Stokes shifts are found at low temperatures; the 2.2-eV luminescence band produced under the photo-excitation in the first exciton region, and the 2.5-eV luminescence band stimulated by photons with energies above the bandgap. The time-resolved photoluminescence measurements have revealed that the 2.2-eV luminescence comprises fast (1.2 μs) and slow (6.4 μs) exponential decay components, whereas the 2.5-eV luminescence shows the time dependence of I(t) ∝ t-0.9. These results suggest that the former band is attributed to the radiative decay of self-trapped excitons, and the latter band would originate from tunneling recombination of holes with the STEL as in the case of lead halides.

  7. Self-Trapped Excitons in Orthorhombic SnBr2

    NASA Astrophysics Data System (ADS)

    Yamasaki, Y.; Ohno, N.

    Luminescence properties of SnBr2 have been studied to reveal the photo-excited exciton relaxation process. Two types of luminescence with large Stokes shifts are found at low temperatures; the 2.2-eV luminescence band produced under the photo-excitation in the first exciton region, and the 2.5-eV luminescence band stimulated by photons with energies above the bandgap. The time-resolved photoluminescence measurements have revealed that the 2.2-eV luminescence comprises fast (1.2 μs) and slow (6.4 μs) exponential decay components, whereas the 2.5-eV luminescence shows the time dependence of I(t)∞ t-0.9. These results suggest that the former band is attributed to the radiative decay of self-trapped excitons, and the latter band would originate from tunneling recombination of holes with the STEL as in the case of lead halides.

  8. U.S. Department of Energy Program of International Technical Cooperation for Research Reactor Utilization

    SciTech Connect

    Chong, D.; Manning, M.; Ellis, R.; Apt, K.; Flaim, S.; Sylvester, K.

    2004-10-03

    The U.S. Department of Energy, National Nuclear Security Administration (DOE/NNSA) has initiated collaborations with the national nuclear authorities of Egypt, Peru, and Romania for the purpose of advancing the commercial potential and utilization of their respective research reactors. Under its Office of International Safeguards ''Sister Laboratory'' program, DOE/NNSA has undertaken numerous technical collaborations over the past decade intended to promote peaceful applications of nuclear technology. Among these has been technical assistance in research reactor applications, such as neutron activation analysis, nuclear analysis, reactor physics, and medical radioisotope production. The current collaborations are intended to provide the subject countries with a methodology for greater commercialization of research reactor products and services. Our primary goal is the transfer of knowledge, both in administrative and technical issues, needed for the establishment of an effective business plan and utilization strategy for the continued operation of the countries' research reactors. Technical consultation, cooperation, and the information transfer provided are related to: identification, evaluation, and assessment of current research reactor capabilities for products and services; identification of opportunities for technical upgrades for new or expanded products and services; advice and consultation on research reactor upgrades and technical modifications; characterization of markets for reactor products and services; identification of competition and estimation of potential for market penetration; integration of technical constraints; estimation of cash flow streams; and case studies.

  9. Fluidized bed reactor utilizing a plate support and method of operating the reactor

    SciTech Connect

    Korenberg, J.

    1984-10-09

    A bed support, and a fluidizing bed reactor incorporating the bed support, the bed support including a horizontal support surface with a centrally disposed conduit for removing tramp material and/or agglomerated material from the reactor. The horizontal support surface has fluidizing air source jet nozzles for directing pressurized air toward the area above the conduit. In a first embodiment, the conduit has downwardly diverging walls. In a second embodiment, the horizontal support surface further includes a bar grate having central fluidizing air source jet nozzles positioned within the conduit. The method of operating the fluidized bed reactor includes directing pressurized air at an angle to the horizontal support surface both for fluidizing the bed and for moving the tramp material and/or agglomerated material toward the conduit for removal from the reactor through the conduit.

  10. Physical adsorption and charge transfer of molecular Br2 on graphene.

    PubMed

    Chen, Zheyuan; Darancet, Pierre; Wang, Lei; Crowther, Andrew C; Gao, Yuanda; Dean, Cory R; Taniguchi, Takashi; Watanabe, Kenji; Hone, James; Marianetti, Chris A; Brus, Louis E

    2014-03-25

    We present a detailed study of gaseous Br2 adsorption and charge transfer on graphene, combining in situ Raman spectroscopy and density functional theory (DFT). When graphene is encapsulated by hexagonal boron nitride (h-BN) layers on both sides, in a h-BN/graphene/h-BN sandwich structure, it is protected from doping by strongly oxidizing Br2. Graphene supported on only one side by h-BN shows strong hole doping by adsorbed Br2. Using Raman spectroscopy, we determine the graphene charge density as a function of pressure. DFT calculations reveal the variation in charge transfer per adsorbed molecule as a function of coverage. The molecular adsorption isotherm (coverage versus pressure) is obtained by combining Raman spectra with DFT calculations. The Fowler-Guggenheim isotherm fits better than the Langmuir isotherm. The fitting yields the adsorption equilibrium constant (∼0.31 Torr(-1)) and repulsive lateral interaction (∼20 meV) between adsorbed Br2 molecules. The Br2 molecule binding energy is ∼0.35 eV. We estimate that at monolayer coverage each Br2 molecule accepts 0.09 e- from single-layer graphene. If graphene is supported on SiO2 instead of h-BN, a threshold pressure is observed for diffusion of Br2 along the (somewhat rough) SiO2/graphene interface. At high pressure, graphene supported on SiO2 is doped by adsorbed Br2 on both sides. PMID:24528378

  11. Development and transfer of fuel fabrication and utilization technology for research reactors

    SciTech Connect

    Travelli, A.; Domagala, R.F.; Matos, J.E.; Snelgrove, J.L.

    1982-01-01

    Approximately 300 research reactors supplied with US-enriched uranium are currently in operation in about 40 countries, with a variety of types, sizes, experiment capabilities and applications. Despite the usefulness and popularity of research reactors, relatively few innovations in their core design have been made in the last fifteen years. The main reason can be better understood by reviewing briefly the history of research reactor fuel technology and enrichment levels. Stringent requirements on the enrichment of the uranium to be used in research reactors were considered and a program was launched to assist research reactors in continuing their operation with the new requirements and with minimum penalties. The goal of the new program, the Reduced Enrichment Research and Test Reactor (RERTR) Program, is to develop the technical means to utilize LEU instead of HEU in research reactors without significant penalties in experiment performance, operating costs, reactor modifications, and safety characteristics. This paper reviews briefly the RERTR Program activities with special emphasis on the technology transfer aspects of interest to this conference.

  12. Lunar Resource Utilization: Development of a Reactor for Volatile Extraction from Regolith

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie E.; Sacksteder, Kurt R.; Nayagam, Vedha

    2007-01-01

    The extraction and processing of planetary resources into useful products, known as In- Situ Resource Utilization (ISRU), will have a profound impact on the future of planetary exploration. One such effort is the RESOLVE (Regolith and Environment Science, Oxygen and Lunar Volatiles Extraction) Project, which aims to extract and quantify these resources. As part of the first Engineering Breadboard Unit, the Regolith Volatiles Characterization (RVC) reactor was designed and built at the NASA Glenn Research Center. By heating and agitating the lunar regolith, loosely bound volatiles, such as hydrogen and water, are released and stored in the reactor for later analysis and collection. Intended for operation on a robotic rover, the reactor features a lightweight, compact design, easy loading and unloading of the regolith, and uniform heating of the regolith by means of vibrofluidization. The reactor performance was demonstrated using regolith simulant, JSC1, with favorable results.

  13. Utilization of the Philippine Research Reactor as a training facility for nuclear power plant operators

    SciTech Connect

    Palabrica, R.J.

    1981-01-01

    The Philippines has a 1-MW swimming-pool reactor facility operated by the Philippine Atomic Energy Commission (PAEC). The reactor is light-water moderated and cooled, graphite reflected, and fueled with 90% enriched uranium. Since it became critical in 1963 it has been utilized for research, radioisotope production, and training. It was used initially in the training of PAEC personnel and other research institutions and universities. During the last few years, however, it has played a key role in training personnel for the Philippine Nuclear Power Project (PNPP).

  14. Spin-orbit relaxation of Br ((2)P(sub 1/2))

    NASA Astrophysics Data System (ADS)

    Johnson, R. O.; Katapski, S. M.; Perram, G. P.; Roh, W. B.; Tate, R. F.

    Pulsed and steady-state photolysis experiments have been conducted to determine the rate coefficients for collisional deactivation of the spin-orbit excited state atomic bromine, Br ((2)P(sub 1/2)). Pulsed lifetime studies for quenching by Br2 and CO2 established absolute rate coefficients at room temperature of k(sub Br2) = 1.2 +/- 10(exp -12) and k(sub CO2) = 1.5 +/- 0.3 x 10(exp -11)/cc/molecule-s. Steady-state photolysis methods were used to determine the quenching rates for the rare gases, N2, O2, H2, D2, NO, NO2, N2O, SF6, CF4, CH4, CO, CO2, COS, SO2, H2S, HBr, HCl, and HI relative to that for Br2.

  15. Trapping molecular bromine: a one-dimensional bromobismuthate complex with Br2 as a linker.

    PubMed

    Adonin, S A; Gorokh, I D; Abramov, P A; Plyusnin, P E; Sokolov, M N; Fedin, V P

    2016-03-01

    The reaction between solid (NMP)n{[BiBr4]}n (1) (NMP = N-methylpyridinium) and Br2, generated in situ in HBr solution, results in the formation of (NMP)3[Bi2Br9]·Br2 (2). In the structure of 2, dibromine molecules connect discrete binuclear [Bi2Br9](3-) anions into an extended network. Complex 2 is thermally stable (up to 150 °C). PMID:26905232

  16. Multi-Reactor Transmutation Analysis Utility (MRTAU,alpha1): Verification

    SciTech Connect

    Andrea Alfonsi; Samuel E. Bays; Cristian Rabiti; Steven J. Piet

    2011-02-01

    Multi-Reactor Transmutation Utility (MRTAU) is a general depletion/decay algorithm under development at INL to support quick assessment of off-normal fuel cycle scenarios of similar nature to well studied reactor and fuel cycle concepts for which isotopic and cross-section data exists. MRTAU has been used in the past for scoping calculations to determine actinide composition evolution over the course of multiple recycles in Light Water Reactor Mixed Oxide and Sodium cooled Fast Reactor. In these applications, various actinide partitioning scenarios of interest were considered. The code has recently been expanded to include fission product generation, depletion and isotopic evolution over multiple recycles. The capability was added to investigate potential partial separations and/or limited recycling technologies such as Melt-Refining, AIROX, DUPIC or other fuel recycle technology where the recycled fuel stream is not completely decontaminated of fission products prior to being re-irradiated in a subsequent reactor pass. This report documents the code's solution methodology and algorithm as well as its solution accuracy compared to the SCALE6.0 software suite.

  17. Laser-induced etching of titanium by Br2 and CCl3Br at 248 nm

    NASA Astrophysics Data System (ADS)

    Tyndall, George W.; Moylan, Christopher R.

    1990-06-01

    A quartz crystal microbalance (QCM) has been used to study the KrF* excimer laser-induced etching of titanium by bromine-containing compounds. The experiment consists of focusing the pulsed UV laser beam at normal incidence onto the surface of a quartz crystal coated with 1 μm of polycrystalline titanium. The removal of titanium from the surface is monitored in real time by measuring the change in the frequency of the quartz crystal. The dependence of the etch rate on etchant pressure and laser fluence was measured and found to be consistent with a two-step etching mechanism. The initial step in the etching of titanium is reaction between the etchant and the surface to form the etch product between laser pulses. The etch product is subsequently removed from the surface during the laser pulse via a laser-induced thermal desorption process. The maximum etch rate obtained in this work was 6.2 Å-pulse-1, indicating that between two and three atomic layers of Ti can be removed per laser pulse. The energy required for desorption of the etch product is calculated to be 172 kJ-mole-1, which is consistent with the sublimation enthalpy of TiBr2 (168 kJ-mole-1). The proposed product in the etching of titanium by Br2 and CCl3Br is thus TiBr2. In the etching of Ti by Br2, formation of TiBr2 proceeds predominantly through the dissociative chemisorption of Br2. In the case of etching with CCl3Br, TiBr2 is formed via chemisorption of Br atoms produced in the gas-phase photodissociation of CCl3Br.

  18. Advanced Pressurized Water Reactor for Improved Resource Utilization: Part I - Survey of Potential Improvements

    SciTech Connect

    Turner, S.E.; Gurley, M.K.; Kirby, K.D.; Mitchell, W. III

    1981-09-15

    This document is an interim report under ACDA BOA AC9NX707, Task Order 80-03, which covers the evaluation of certain potential improvements in pressurized water reactor designs intended to enhance uranium fuel utilization. The objective of these evaluations is to seek advanced, non-retrofittable improvements that could possibly be commercialized by the end of the century, and, on the basis of a preliminary evaluation, to select compatible improvements for incorporation into a composite advanced pressurized water reactor concept. The principal areas of investigation include reduced parasitic absorption of neutrons (Task 1), reduced neutron leakage (Task 2), and alternative fuel design concepts (Task 3). To the extent possible, the advanced concept developed in an earlier study (Retrofittable Modifications to Pressurized Water Reactors for Improved Resource Utilization, SSA-128, October 1980) is used as a basis in developing the advanced composite concept. The reference design considered typical of present PWR commercial practice is the system described in RESAR-414, Reference Safety Analysis Report, Westinghouse Nuclear Energy Systems, October 1976.

  19. Preliminary study on weapon grade uranium utilization in molten salt reactor miniFUJI

    SciTech Connect

    Aji, Indarta Kuncoro; Waris, A.

    2014-09-30

    Preliminary study on weapon grade uranium utilization in 25MWth and 50MWth of miniFUJI MSR (molten salt reactor) has been carried out. In this study, a very high enriched uranium that we called weapon grade uranium has been employed in UF{sub 4} composition. The {sup 235}U enrichment is 90 - 95 %. The results show that the 25MWth miniFUJI MSR can get its criticality condition for 1.56 %, 1.76%, and 1.96% of UF{sub 4} with {sup 235}U enrichment of at least 93%, 90%, and 90%, respectively. In contrast, the 50 MWth miniFUJI reactor can be critical for 1.96% of UF{sub 4} with {sup 235}U enrichment of at smallest amount 95%. The neutron spectra are almost similar for each power output.

  20. Kinetics of the Br2-CH3CHO Photochemical Chain Reaction

    NASA Technical Reports Server (NTRS)

    Nicovich, J. M.; Shackelford, C. J.; Wine, P. H.

    1997-01-01

    Time-resolved resonance fluorescence spectroscopy was employed in conjunction with laser flash photolysis of Br2 to study the kinetics of the two elementary steps in the photochemical chain reaction nBr2 + nCH3CHO + hv yields nCH3CBrO + nHBr. In the temperature range 255-400 K, the rate coefficient for the reaction Br((sup 2)P(sub 3/2)) + CH3CHO yields CH3CO + HBr is given by the Arrhenius expression k(sub 6)(T) = (1.51 +/- 0.20) x 10(exp -11) exp(-(364 +/- 41)/T)cu cm/(molecule.s). At 298 K, the reaction CH3CO + Br2 yields CH3CBrO + Br proceeds at a near gas kinetic rate, k(sub 7)(298 K) = (1.08 +/- 0.38) x 10(exp -10)cu cm/(molecule.s).

  1. Integrated biogas upgrading and hydrogen utilization in an anaerobic reactor containing enriched hydrogenotrophic methanogenic culture.

    PubMed

    Luo, Gang; Angelidaki, Irini

    2012-11-01

    Biogas produced by anaerobic digestion, is mainly used in a gas motor for heat and electricity production. However, after removal of CO(2) , biogas can be upgraded to natural gas quality, giving more utilization possibilities, such as utilization as autogas, or distant utilization by using the existing natural gas grid. The current study presents a new biological method for biogas upgrading in a separate biogas reactor, containing enriched hydrogenotrophic methanogens and fed with biogas and hydrogen. Both mesophilic- and thermophilic anaerobic cultures were enriched to convert CO(2) to CH(4) by addition of H(2) . Enrichment at thermophilic temperature (55°C) resulted in CO(2) and H(2) bioconversion rate of 320 mL CH(4) /(gVSS h), which was more than 60% higher than that under mesophilic temperature (37°C). Different dominant species were found at mesophilic- and thermophilic-enriched cultures, as revealed by PCR-DGGE. Nonetheless, they all belonged to the order Methanobacteriales, which can mediate hydrogenotrophic methanogenesis. Biogas upgrading was then tested in a thermophilic anaerobic reactor under various operation conditions. By continuous addition of hydrogen in the biogas reactor, high degree of biogas upgrading was achieved. The produced biogas had a CH(4) content, around 95% at steady-state, at gas (mixture of biogas and hydrogen) injection rate of 6 L/(L day). The increase of gas injection rate to 12 L/(L day) resulted in the decrease of CH(4) content to around 90%. Further study showed that by decreasing the gas-liquid mass transfer by increasing the stirring speed of the mixture the CH(4) content was increased to around 95%. Finally, the CH(4) content around 90% was achieved in this study with the gas injection rate as high as 24 L/(L day). PMID:22615033

  2. Preliminary LEU fuel cycle analyses for the Belgian BR2 reactor

    SciTech Connect

    Deen, J.R.; Snelgrove, J.L.

    1986-01-01

    Fuel cycle calculations have been performed with reference HEU fuel and LEU fuel using Cd wires or boron as burnable absorbers. The /sup 235/U content in the LEU element has increased 20% to 480g compared to the reference HEU element. The number of fuel plates has remained unchanged while the fuel meat thickness has increased to 0.76 mm from 0.51 mm. The LEU meat density is 5.1 Mg U/m/sup 3/. The reference fuel cycle was a 31 element core operating at 56 MW with a 19.8 day cycle length and eight fresh elements loaded per cycle. Comparable fuel cycle characteristics can be achieved using the proposed LEU fuel element with either Cd wires or boron burnable absorbers. The neutron flux for E/sub n/ > 1 eV changes very little (<5%) in LEU relative to HEU cores. Thermal flux reductions are 5 to 10% in non-fueled positions, and 20 to 30% in fuel elements.

  3. Estimation of steady-state and transcient power distributions for the RELAP analyses of the 1963 loss-of-flow and loss-of-pressure tests at BR2.

    SciTech Connect

    Dionne, B.; Tzanos, C. P.

    2011-05-23

    To support the safety analyses required for the conversion of the Belgian Reactor 2 (BR2) from highly-enriched uranium (HEU) to low-enriched uranium (LEU) fuel, the simulation of a number of loss-of-flow tests, with or without loss of pressure, has been undertaken. These tests were performed at BR2 in 1963 and used instrumented fuel assemblies (FAs) with thermocouples (TC) imbedded in the cladding as well as probes to measure the FAs power on the basis of their coolant temperature rise. The availability of experimental data for these tests offers an opportunity to better establish the credibility of the RELAP5-3D model and methodology used in the conversion analysis. In order to support the HEU to LEU conversion safety analyses of the BR2 reactor, RELAP simulations of a number of loss-of-flow/loss-of-pressure tests have been undertaken. Preliminary analyses showed that the conservative power distributions used historically in the BR2 RELAP model resulted in a significant overestimation of the peak cladding temperature during the transient. Therefore, it was concluded that better estimates of the steady-state and decay power distributions were needed to accurately predict the cladding temperatures measured during the tests and establish the credibility of the RELAP model and methodology. The new approach ('best estimate' methodology) uses the MCNP5, ORIGEN-2 and BERYL codes to obtain steady-state and decay power distributions for the BR2 core during the tests A/400/1, C/600/3 and F/400/1. This methodology can be easily extended to simulate any BR2 core configuration. Comparisons with measured peak cladding temperatures showed a much better agreement when power distributions obtained with the new methodology are used.

  4. Licensing for tritium production in a commercial light water reactor: A utility view

    SciTech Connect

    Chardos, J.S.; Sorensen, G.C.; Erickson, L.W.

    2000-07-01

    In a December 1995 Record of Decision for the Final Programmatic Environmental Impact Statement for Tritium Supply and Recycling, the US Department of Energy (DOE) decided to pursue a dual-track approach to determine the preferred option for future production of tritium for the nuclear weapons stockpile. The two options to be pursued were (a) the Accelerator Production of Tritium and (b) the use of commercial light water reactors (CLWRs). DOE committed to select one of these two options as the primary means of tritium production by the end of 1998. The other option would continue to be pursued as a backup to the primary option. The Tennessee Valley Authority (TVA) became involved in the tritium program in early 1996, in response to an inquiry from Pacific Northwest National Laboratory (PNNL) for an expression of interest by utilities operating nuclear power plants (NPPs). In June 1996, TVA was one of two utilities to respond to a request for proposals to irradiate lead test assemblies (LTAs) containing tritium-producing burnable absorber rods (TPBARs). TVA proposed that the LTAs be placed in Watts Bar NPP Unit 1 (WBN). TVA participated with DOE (the Defense Programs Office of CLWR Tritium Production), PNNL, and Westinghouse Electric Company (Westinghouse) in the design process to ensure that the TPBARs would be compatible with safe operation of WBN. Following US Nuclear Regulatory Commission (NRC) issuance of a Safety Evaluation Report (SER) (NUREG-1607), TVA submitted a license amendment request to the NRC for approval to place four LTAs, containing eight TPBARs each, in WBN during the September 1997 refueling outage. In December 1998, DOE announced the selection of the CLWR program as the primary option for tritium production and identified the TVA WBN and Sequoyah NPP (SQN) Units 1 and 2 (SQN-1 and SQN-2, respectively) reactors as the preferred locations to perform tritium production. TVA will prepare license amendment requests for the three plants (WBN, SQN-1

  5. Caveats for poly(methimazolyl)borate chemistry: the novel inorganic heterocycles [H2C(mt)2BR2]Cl (mt = methimazolyl; BR2 = BH2, BH(mt), 9-BBN).

    PubMed

    Crossley, Ian R; Hill, Anthony F; Humphrey, Elizabeth R; Smith, Matthew K; Tshabang, Never; Willis, Anthony C

    2004-08-21

    Whilst frequently used for reactions of poly(methimazolyl)borates, dichloromethane is not an innocent solvent, but rather slowly forms heterocyclic salts [H(2)C(mt)(2)BR(2)]Cl, three examples of which (BR(2) = BH(2), BH(mt), 9-borabicyclononyl) have been structurally characterised to confirm the unprecedented B(NCS)(2)C connectivity. PMID:15306929

  6. Computations on the primary photoreaction of Br2 with CO2: stepwise vs concerted addition of Br atoms.

    PubMed

    Xu, Kewei; Korter, Timothy M; Braiman, Mark S

    2015-04-01

    It was proposed previously that Br2-sensitized photolysis of liquid CO2 proceeds through a metastable primary photoproduct, CO2Br2. Possible mechanisms for such a photoreaction are explored here computationally. First, it is shown that the CO2Br radical is not stable in any geometry. This rules out a free-radical mechanism, for example, photochemical splitting of Br2 followed by stepwise addition of Br atoms to CO2-which in turn accounts for the lack of previously observed Br2+CO2 photochemistry in gas phases. A possible alternative mechanism in liquid phase is formation of a weakly bound CO2:Br2 complex, followed by concerted photoaddition of Br2. This hypothesis is suggested by the previously published spectroscopic detection of a binary CO2:Br2 complex in the supersonically cooled gas phase. We compute a global binding-energy minimum of -6.2 kJ mol(-1) for such complexes, in a linear geometry. Two additional local minima were computed for perpendicular (C2v) and nearly parallel asymmetric planar geometries, both with binding energies near -5.4 kJ mol(-1). In these two latter geometries, C-Br and O-Br bond distances are simultaneously in the range of 3.5-3.8 Å, that is, perhaps suitable for a concerted photoaddition under the temperature and pressure conditions where Br2 + CO2 photochemistry has been observed. PMID:25767936

  7. Manganese dioxide causes spurious gold values in flame atomic-absorption readings from HBr-Br2 digestions

    USGS Publications Warehouse

    Campbell, W.L.

    1981-01-01

    False readings, apparently caused by the presence of high concentrations of manganese dioxide, have been observed in our current flame atomic-absorption procedure for the determination of gold. After a hydrobromic acid (HBr)-bromine (Br2) leach, simply heating the sample to boiling to remove excess Br2 prior to extraction with methyl-isobutyl-ketone (MIBK) eliminates these false readings. ?? 1981.

  8. Bromine-rich Zinc Bromides: Zn6Br12(18-crown-6)2×(Br2)5, Zn4Br8(18-crown-6)2×(Br2)3, and Zn6Br12(18-crown-6)2×(Br2)2.

    PubMed

    Hausmann, David; Feldmann, Claus

    2016-06-20

    The bromine-rich zinc bromides Zn6Br12(18-crown-6)2×(Br2)5 (1), Zn4Br8(18-crown-6)2×(Br2)3 (2), and Zn6Br12(18-crown-6)2×(Br2)2 (3) are prepared by reaction of ZnBr2, 18-crown-6, and elemental bromine in the ionic liquid [MeBu3N][N(Tf)2] (N(Tf)2 = bis(trifluoromethylsulfonyl)amide). Zn6Br12(18-crown-6)2×(Br2)5 (1) is formed instantaneously by the reaction. Even at room temperature, compound 1 releases bromine, which was confirmed by thermogravimetry (TG) and mass spectrometry (MS). The release of Br2 can also be directly followed by the color and density of the title compounds. With controlled conditions (2 weeks, 25 °C, absence of excess Br2) Zn6Br12(18-crown-6)2×(Br2)5 (1) slowly releases bromine with conconcurrent generation of Zn4Br8(18-crown-6)2×(Br2)3 (2) (in ionic liquid) and Zn6Br12(18-crown-6)2×(Br2)2 (3) (in inert oil). All bromine-rich zinc bromides contain voluminous uncharged (e.g., Zn3Br6(18-crown-6), Zn2Br4(18-crown-6)) or ionic (e.g., [Zn2Br3(18-crown-6)](+), [(Zn2Br6)×(Br2)2](2-)) building units with dibromine molecules between the Zn oligomers and partially interconnecting the Zn-containing building units. Due to the structural similarity, the bromine release is possible via crystal-to-crystal transformation with retention of the crystal shape. PMID:27281122

  9. NRC review of Electric Power Research Institute's Advanced Light Reactor Utility Requirements Document - Program summary, Project No. 669

    SciTech Connect

    Not Available

    1992-08-01

    The staff of the US Nuclear Regulatory Commission has prepared Volume 1 of a safety evaluation report (SER), NRC Review of Electric Power Research Institute's Advanced Light Water Reactor Utility Requirements Document -- Program Summary,'' to document the results of its review of the Electric Power Research Institute's Advanced Light Water Reactor Utility Requirements Document.'' This SER provides a discussion of the overall purpose and scope of the Requirements Document, the background of the staff's review, the review approach used by the staff, and a summary of the policy and technical issues raised by the staff during its review.

  10. Fourier transform infrared spectroscopic study of Br 2O and OBrO

    NASA Astrophysics Data System (ADS)

    Chu, Liang T.; Li, Zhuangjie

    2000-11-01

    Vibrational frequencies of gaseous Br 2O and OBrO were observed using the Fourier transform infrared spectrometer. For the first time, bands at 629.0 cm -1 ( ν3) and 532.9 cm -1 ( ν1) were recorded for both Br-O asymmetric and symmetric stretching vibrations of gaseous Br 2O. Two fundamental vibrations were observed at 798.7 cm-1 (ν 1) and 846.3 cm-1 (ν 3) for the O 18BrO radical. In addition, two new peaks at 2333 cm -1 and 668 cm -1 were observed in a HOBr spectrum. They are tentatively assigned to the H-Br and Br-O stretching vibrations of a HOBr isomer on the basis of ab initio computational results.

  11. Nqrs Data for C26H35Br2CuP2 (Subst. No. 1603)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume B 'Substances Containing C10H16 … Zn' of Volume 48 'Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III 'Condensed Matter'. It contains an extract of Section '3.2 Data tables' of the Chapter '3 Nuclear quadrupole resonance data' providing the NQRS data for C26H35Br2CuP2 (Subst. No. 1603)

  12. Analysis of neutron flux distribution for the validation of computational methods for the optimization of research reactor utilization.

    PubMed

    Snoj, L; Trkov, A; Jaćimović, R; Rogan, P; Zerovnik, G; Ravnik, M

    2011-01-01

    In order to verify and validate the computational methods for neutron flux calculation in TRIGA research reactor calculations, a series of experiments has been performed. The neutron activation method was used to verify the calculated neutron flux distribution in the TRIGA reactor. Aluminium (99.9 wt%)-Gold (0.1 wt%) foils (disks of 5mm diameter and 0.2mm thick) were irradiated in 33 locations; 6 in the core and 27 in the carrousel facility in the reflector. The experimental results were compared to the calculations performed with Monte Carlo code MCNP using detailed geometrical model of the reactor. The calculated and experimental normalized reaction rates in the core are in very good agreement for both isotopes indicating that the material and geometrical properties of the reactor core are modelled well. In conclusion one can state that our computational model describes very well the neutron flux and reaction rate distribution in the reactor core. In the reflector however, the accuracy of the epithermal and thermal neutron flux distribution and attenuation is lower, mainly due to lack of information about the material properties of the graphite reflector surrounding the core, but the differences between measurements and calculations are within 10%. Since our computational model properly describes the reactor core it can be used for calculations of reactor core parameters and for optimization of research reactor utilization. PMID:20855215

  13. Utilization of coal fly ash in solidification of liquid radioactive waste from research reactor.

    PubMed

    Osmanlioglu, Ahmet Erdal

    2014-05-01

    In this study, the potential utilization of fly ash was investigated as an additive in solidification process of radioactive waste sludge from research reactor. Coal formations include various percentages of natural radioactive elements; therefore, coal fly ash includes various levels of radioactivity. For this reason, fly ashes have to be evaluated for potential environmental implications in case of further usage in any construction material. But for use in solidification of radioactive sludge, the radiological effects of fly ash are in the range of radioactive waste management limits. The results show that fly ash has a strong fixing capacity for radioactive isotopes. Specimens with addition of 5-15% fly ash to concrete was observed to be sufficient to achieve the target compressive strength of 20 MPa required for near-surface disposal. An optimum mixture comprising 15% fly ash, 35% cement, and 50% radioactive waste sludge could provide the solidification required for long-term storage and disposal. The codisposal of radioactive fly ash with radioactive sludge by solidification decreases the usage of cement in solidification process. By this method, radioactive fly ash can become a valuable additive instead of industrial waste. This study supports the utilization of fly ash in industry and the solidification of radioactive waste in the nuclear industry. PMID:24638274

  14. Electronic properties of PbCl2 and PbBr2 using Compton scattering technique.

    PubMed

    Ahmed, G; Sharma, Y; Ahuja, B L

    2009-06-01

    We present the electron momentum densities of PbCl(2) and PbBr(2) using 661.65 keV gamma-rays from 20 Ci (137)Cs source. To supplement our experimental investigations, we also report energy bands, density of states, Mulliken's population and Compton profiles of PbCl(2) and PbBr(2) using linear combination of atomic orbitals within Hartree-Fock and density functional theories. The energy bands are also computed employing full potential linearized augmented plane wave (FP-LAPW) method. Compton profiles are also analyzed in terms of equal-valence-electron-density scale. It shows that PbCl(2) is more covalent than PbBr(2), which is in agreement with the Mulliken's population analysis. It is seen that the Hartree-Fock and density functional theory based Compton line shapes show similar type of deviations from the experimental data. The luminescence properties of these halides are explained on the basis of energy band and density of states. PMID:19269187

  15. Dibromine Monoxide, Br2O: The Rotational Spectrum and Molecular Properties

    NASA Technical Reports Server (NTRS)

    Mueller, Holger S. P.; Cohen, Edward A.

    1997-01-01

    The rotational spectra of (79)Br2O, (79)BrO(81)Br, and Br2O in their ground vibrational states as well as (79)BrO(81)Br in its v (sub 2) = 1 state have been studied in selected regions between 90 and 523 GHz. Transitions involving a large range of quantum numbers, 6 less than or equal to J less than or equal to 123 and 0 less than or equal to K (sub a) less than or equal to 12, have been observed permitting precise rotational and a large set of centrifugal distortion constants to be determined. All isotopic species as well as the excited state data were fit simultaneously. Ground-state effective and average structural parameters as well as an estimate of the equilibrium structure have been derived. The quartic distortion constants were used for a calculation of the harmonic force field. The complete quadrupole tensor has been determined. Its diagonalization reveals a largely covalent BrO bond with little pi-bonding. The derived properties of Br2O are compared with those of related compounds such as Cl2O, HOBR, and HOCl.

  16. Steady-State Thermal-Hydraulics Analyses for the Conversion of BR2 to Low Enriched Uranium Fuel

    SciTech Connect

    Licht, J.; Bergeron, A.; Dionne, B.; Van den Branden, G; Kalcheva, S; Sikik, E; Koonen, E

    2015-01-01

    The code PLTEMP/ANL version 4.2 was used to perform the steady-state thermal-hydraulic analyses of the BR2 research reactor for conversion from Highly-Enriched to Low Enriched Uranium fuel (HEU and LEU, respectively). Calculations were performed to evaluate different fuel assemblies with respect to the onset of nucleate boiling (ONB), flow instability (FI), critical heat flux (CHF) and fuel temperature at beginning of cycle conditions. The fuel assemblies were characteristic of fresh fuel (0% burnup), highest heat flux (16% burnup), highest power (32% burnup) and highest burnup (46% burnup). Results show that the high heat flux fuel element is limiting for ONB, FI, and CHF, for both HEU and LEU fuel, but that the high power fuel element produces similar margin in a few cases. The maximum fuel temperature similarly occurs in both the high heat flux and high power fuel assemblies for both HEU and LEU fuel. A sensitivity study was also performed to evaluate the variation in fuel temperature due to uncertainties in the thermal conductivity degradation associated with burnup.

  17. Utilization of the High Flux Isotope Reactor at Oak Ridge National Laboratory

    SciTech Connect

    Selby, Douglas L; Bilheux, Hassina Z; Meilleur, Flora; Jones, Amy; Bailey, William Barton; Vandergriff, David H

    2015-01-01

    This paper addresses several aspects of the scientific utilization of the Oak Ridge National Laboratory High Flux Isotope Reactor (HFIR). Topics to be covered will include: 1) HFIR neutron scattering instruments and the formal instrument user program; 2) Recent upgrades to the neutron scattering instrument stations at the reactor, and 3) eMod a new tool for addressing instrument modifications and providing configuration control and design process for scientific instruments at HFIR and the Spallation Neutron Source (SNS). There are 15 operating neutron instrument stations at HFIR with 12 of them organized into a formal user program. Since the last presentation on HFIR instruments at IGORR we have installed a Single Crystal Quasi-Laue Diffractometer instrument called IMAGINE; and we have made significant upgrades to HFIR neutron scattering instruments including the Cold Triple Axis Instrument, the Wide Angle Neutron Diffractometer, the Powder Diffractometer, and the Neutron Imaging station. In addition, we have initiated upgrades to the Thermal Triple Axis Instrument and the Bio-SANS cold neutron instrument detector system. All of these upgrades are tied to a continuous effort to maintain a high level neutron scattering user program at the HFIR. For the purpose of tracking modifications such as those mentioned and configuration control we have been developing an electronic system for entering instrument modification requests that follows a modification or instrument project through concept development, design, fabrication, installation, and commissioning. This system, which we call eMod, electronically leads the task leader through a series of questions and checklists that then identifies such things as ES&H and radiological issues and then automatically designates specific individuals for the activity review process. The system has been in use for less than a year and we are still working out some of the inefficiencies, but we believe that this will become a very

  18. Structures, molecular orbitals and UV-vis spectra investigations on Br2C6H4: a computational study.

    PubMed

    Wang, Tsang-Hsiu; Hsu, Chen-Shuo; Huang, Wen-Lin; Lo, Yih-Hsing

    2013-11-01

    The dibromobenzenes (1,2-, 1,3- and 1,4-Br2C6H4) have been studied by theoretical methods. The structures of these species are optimized and the structural characteristics are determined by density functional theory (DFT) and the second order Møller-Plesset perturbation theory (MP2) levels. The geometrical structures of Br2C6H4 show a little distortion of benzene ring due to the substitution of highly electronegativity of bromine atoms. The electronegativity of bromine atoms in 1,4-Br2C6H4 is predicted to be more negative than 1,2- and 1,3-Br2C6H4. In addition, dipole moment and frontier molecular orbitals (FMOs) of these Br2C6H4 are performed as well. The 1,4-Br2C6H4 is slightly more reactive than 1,2- and 1,3-Br2C6H4 because of its small HOMO-LUMO energy gap. The simulated UV-vis spectra are investigated by time-dependent density functional theory (TD-DFT) approach, which are in excellent agreement with the available experimental value. Our calculations show that a few of absorption features are between 140nm and 250nm, which is in ultraviolet C range, and the red shift of 1,3- and 1,4-Br2C6H4 are predicted. Moreover, the UV absorption features of these Br2C6H4 in water or methanol are predicted to be more intense than in gas phase due to solvent effect. PMID:23892349

  19. Utilization of the Recycle Reactor in Determining Kinetics of Gas-Solid Catalytic Reactions.

    ERIC Educational Resources Information Center

    Paspek, Stephen C.; And Others

    1980-01-01

    Describes a laboratory scale reactor that determines the kinetics of a gas-solid catalytic reaction. The external recycle reactor construction is detailed with accompanying diagrams. Experimental details, application of the reactor to CO oxidation kinetics, interphase gradients, and intraphase gradients are discussed. (CS)

  20. Observations of Cl2, Br2, and I2 in coastal marine air

    NASA Astrophysics Data System (ADS)

    Finley, B. D.; Saltzman, E. S.

    2008-11-01

    Cl2, Br2, and I2 were measured in coastal Pacific air from 2 to 29 January 2006. Air was sampled at 10 m over the sea surface near the end of Scripps Pier (La Jolla, California). The measurements were made using atmospheric pressure chemical ionization with tandem mass spectrometry (APCI/MS/MS). Over the course of this study, Cl2, Br2, and I2 levels ranged from below detection limits of 1.0, 0.5, and 0.2 ppt, respectively, to maxima of 26, 19, and 8 ppt, respectively. Mean dihalogen levels for the study period were 2.3 ± 1 ppt for Cl2, 2.3 ± 0.4 ppt for Br2, and 0.7 ± 0.1 ppt for I2 (expressed as geometric mean ±1 geometric standard error). The mixed dihalogens BrCl, ICl, and IBr had geometric mean levels below 0.3 ± 1 ppt and never exceeded their detection limits of 0.5 ppt. Consistent patterns of diurnal variability were observed for Cl2 and I2, with Cl2 maxima during daytime and I2 appearing almost exclusively at night. The detection of I2 appeared to be related to the passage of air over nearby kelp beds. The observed dihalogen levels suggest that (1) chlorine atom oxidation of hydrocarbons makes a significant contribution to the formation of ozone and (2) halogen atom oxidation of airborne mercury contributes to mercury deposition in polluted coastal air.

  1. A Compact Torus Fusion Reactor Utilizing a Continuously Generated Strings of CT's. The CT String Reactor, CTSR.

    SciTech Connect

    Hartman, C W; Reisman, D B; McLean, H S; Thomas, J

    2007-05-30

    A fusion reactor is described in which a moving string of mutually repelling compact toruses (alternating helicity, unidirectional Btheta) is generated by repetitive injection using a magnetized coaxial gun driven by continuous gun current with alternating poloidal field. An injected CT relaxes to a minimum magnetic energy equilibrium, moves into a compression cone, and enters a conducting cylinder where the plasma is heated to fusion-producing temperature. The CT then passes into a blanketed region where fusion energy is produced and, on emergence from the fusion region, the CT undergoes controlled expansion in an exit cone where an alternating poloidal field opens the flux surfaces to directly recover the CT magnetic energy as current which is returned to the formation gun. The CT String Reactor (CTSTR) reactor satisfies all the necessary MHD stability requirements and is based on extrapolation of experimentally achieved formation, stability, and plasma confinement. It is supported by extensive 2D, MHD calculations. CTSTR employs minimal external fields supplied by normal conductors, and can produce high fusion power density with uniform wall loading. The geometric simplicity of CTSTR acts to minimize initial and maintenance costs, including periodic replacement of the reactor first wall.

  2. Awareness, Preference, Utilization, and Messaging Research for the Spallation Neutron Source and High Flux Isotope Reactor

    SciTech Connect

    Bryant, Rebecca; Kszos, Lynn A

    2011-03-01

    Oak Ridge National Laboratory (ORNL) offers the scientific community unique access to two types of world-class neutron sources at a single site - the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR). The 85-MW HFIR provides one of the highest steady-state neutron fluxes of any research reactor in the world, and the SNS is one of the world's most intense pulsed neutron beams. Management of these two resources is the responsibility of the Neutron Sciences Directorate (NScD). NScD commissioned this survey research to develop baseline information regarding awareness of and perceptions about neutron science. Specific areas of investigative interest include the following: (1) awareness levels among those in the scientific community about the two neutron sources that ORNL offers; (2) the level of understanding members of various scientific communities have regarding benefits that neutron scattering techniques offer; and (3) any perceptions that negatively impact utilization of the facilities. NScD leadership identified users of two light sources in North America - the Advanced Photon Source (APS) at Argonne National Laboratory and the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory - as key publics. Given the type of research in which these scientists engage, they would quite likely benefit from including the neutron techniques available at SNS and HFIR among their scientific investigation tools. The objective of the survey of users of APS, NSLS, SNS, and HFIR was to explore awareness of and perceptions regarding SNS and HFIR among those in selected scientific communities. Perceptions of SNS and FHIR will provide a foundation for strategic communication plan development and for developing key educational messages. The survey was conducted in two phases. The first phase included qualitative methods of (1) key stakeholder meetings; (2) online interviews with user administrators of APS and NSLS; and (3) one-on-one interviews

  3. Thermal properties for the thermal-hydraulics analyses of the BR2 maximum nominal heat flux.

    SciTech Connect

    Dionne, B.; Kim, Y. S.; Hofman, G. L.

    2011-05-23

    This memo describes the assumptions and references used in determining the thermal properties for the various materials used in the BR2 HEU (93% enriched in {sup 235}U) to LEU (19.75% enriched in {sup 235}U) conversion feasibility analysis. More specifically, this memo focuses on the materials contained within the pressure vessel (PV), i.e., the materials that are most relevant to the study of impact of the change of fuel from HEU to LEU. This section is regrouping all of the thermal property tables. Section 2 provides a summary of the thermal properties in form of tables while the following sections present the justification of these values. Section 3 presents a brief background on the approach used to evaluate the thermal properties of the dispersion fuel meat and specific heat capacity. Sections 4 to 7 discuss the material properties for the following materials: (i) aluminum, (ii) dispersion fuel meat (UAlx-Al and U-7Mo-Al), (iii) beryllium, and (iv) stainless steel. Section 8 discusses the impact of irradiation on material properties. Section 9 summarizes the material properties for typical operating temperatures. Appendix A elaborates on how to calculate dispersed phase's volume fraction. Appendix B shows the evolution of the BR2 maximum heat flux with burnup.

  4. Photolysis of Br2 in CCl4 studied by time-resolved X-ray scattering.

    PubMed

    Kong, Qingyu; Lee, Jae Hyuk; Lo Russo, Manuela; Kim, Tae Kyu; Lorenc, Maciej; Cammarata, Marco; Bratos, Savo; Buslaps, Thomas; Honkimaki, Veijo; Ihee, Hyotcherl; Wulff, Michael

    2010-03-01

    A time-resolved X-ray solution scattering study of bromine molecules in CCl(4) is presented as an example of how to track atomic motions in a simple chemical reaction. The structures of the photoproducts are tracked during the recombination process, geminate and non-geminate, from 100 ps to 10 micros after dissociation. The relaxation of hot Br(2)(*) molecules heats the solvent. At early times, from 0.1 to 10 ns, an adiabatic temperature rise is observed, which leads to a pressure gradient that forces the sample to expand. The expansion starts after about 10 ns with the laser beam sizes used here. When thermal artefacts are removed by suitable scaling of the transient solvent response, the excited-state solute structures can be obtained with high fidelity. The analysis shows that 30% of Br(2)(*) molecules recombine directly along the X potential, 60% are trapped in the A/A' state with a lifetime of 5.5 ns, and 10% recombine non-geminately via diffusive motion in about 25 ns. The Br-Br distance distribution in the A/A' state peaks at 3.0 A. PMID:20164648

  5. Spin Excitations and Phonon Anomaly in Quasi-1D Spiral Magneti CuBr2

    NASA Astrophysics Data System (ADS)

    Li, Yuan; Wang, Chong; Yu, Daiwei; Wang, Lichen; Wang, Fa; Iida, Kazuki; Kamazawa, Kazuya; Wakimoto, Shuichi

    CuBr2 can be considered as a model quasi-one-dimensional (quasi-1D) spin-1/2 magnet, in which the frustrating ferromagnetic nearest-neighbor and antiferromagnetic next-nearest-neighbor exchange interactions give rise to a cycloidal magnetic order below TN = 73 K. The removal of inversion symmetry by the magnetic order also makes the material a type-II multiferroic system with a remarkably simple crystal structure. Using time-of-flight inelastic neutron scattering spectroscopy, we have determined the spin-wave as well as phonon spectra throughout the entire Brillouin zone. The spin-wave spectrum exhibits pronounced anisotropy and magnon damping, consistent with the material's quasi-1D nature and the non-colinear spin structure. The phonon spectrum exhibits dramatic discontinuities in the dispersion across the quasi-1D magnetic wave vector, indicative of strong magnetoelastic coupling and possibly of a spin-orbital texture that comes along with the spin correlations.

  6. Photodissociation of Br2 molecules in an intense femtosecond laser field

    NASA Astrophysics Data System (ADS)

    Zhang, Jian; Zhang, Shian; Yang, Yan; Sun, Shengzhi; Wu, Hua; Li, Jing; Chen, Yuting; Jia, Tianqing; Wang, Zugeng; Kong, Fanao; Sun, Zhenrong

    2014-11-01

    We experimentally demonstrate the photodissociation process of Br2 molecules in the intense femtosecond laser field by a dc-sliced ion velocity map imaging technique. We show that four fragment ions B rn +(n =1 -4 ) are observed, and their kinetic energy increases while their angular distribution decreases with the increase of the charge number. We prove that the low (or high) charged fragment ions result from the photodissociation of the low (or high) charged parent ions. We explain the changes of the kinetic energy and angular distribution in these fragment ions by considering the potential energy curves of these parent ions that involve both the interaction of the Coulomb repulsive energy and chemical bonding energy. We also explain the experimental observation that the measured kinetic energy release in the experiment is much smaller than the theoretical calculation by enhanced ionization at a critical distance.

  7. Magnetic torque measurements of TPP[Fe(Pc)Br2]2

    NASA Astrophysics Data System (ADS)

    Inoue, M.; Torizuka, K.; Tajima, H.; Matsuda, M.; Yu, D. E. C.; Naito, T.; Inabe, T.; Hanasaki, N.

    2010-06-01

    Magnetic torque measurements of TPP[Fe(Pc)Br2]2 are reported. The torque curves for the magnetic field rotated within the ac plane exhibit a two-fold symmetry. The temperature dependences of the torque amplitudes divided by the square of the field strength (τφ=45/B2) exhibit a drastic field dependence below 12 K. This field dependence is attributable to the fluctuation in the spontaneous magnetization that appears below 4.5 K. The torque curves for the field rotated within the ab plane exhibit four-fold symmetry. The curves are sinusoidal above 18 K and exhibit saw-toothed shapes below ˜12 K and complicated shapes below 8 K. The complicated shapes suggest that both d-electrons and π-electrons form a magnetic order below 8 K.

  8. Advanced Burner Reactor with Breed-and-Burn Thorium Blankets for Improved Economics and Resource Utilization

    SciTech Connect

    Greenspan, Ehud

    2015-11-04

    This study assesses the feasibility of designing Seed and Blanket (S&B) Sodium-cooled Fast Reactor (SFR) to generate a significant fraction of the core power from radial thorium fueled blankets that operate on the Breed-and-Burn (B&B) mode without exceeding the radiation damage constraint of presently verified cladding materials. The S&B core is designed to maximize the fraction of neutrons that radially leak from the seed (or “driver”) into the subcritical blanket and reduce neutron loss via axial leakage. The blanket in the S&B core makes beneficial use of the leaking neutrons for improved economics and resource utilization. A specific objective of this study is to maximize the fraction of core power that can be generated by the blanket without violating the thermal hydraulic and material constraints. Since the blanket fuel requires no reprocessing along with remote fuel fabrication, a larger fraction of power from the blanket will result in a smaller fuel recycling capacity and lower fuel cycle cost per unit of electricity generated. A unique synergism is found between a low conversion ratio (CR) seed and a B&B blanket fueled by thorium. Among several benefits, this synergism enables the very low leakage S&B cores to have small positive coolant voiding reactivity coefficient and large enough negative Doppler coefficient even when using inert matrix fuel for the seed. The benefits of this synergism are maximized when using an annular seed surrounded by an inner and outer thorium blankets. Among the high-performance S&B cores designed to benefit from this unique synergism are: (1) the ultra-long cycle core that features a cycle length of ~7 years; (2) the high-transmutation rate core where the seed fuel features a TRU CR of 0.0. Its TRU transmutation rate is comparable to that of the reference Advanced Burner Reactor (ABR) with CR of 0.5 and the thorium blanket can generate close to 60% of the core power; but requires only one sixth of the reprocessing and

  9. Modelling of magnetic satellite intensity in the neutron diffraction of an incommensurate helical structure: NiBr 2 and Ni 0.91Fe 0.09Br 2

    NASA Astrophysics Data System (ADS)

    Day, P.; Moore, M. W.; Wilkinson, C.; Ziebeck, K. R. A.

    1985-05-01

    We describe the application of a neutron multidetector diffractometer (D16, I.L.L.) to the study of the incommensurate helical magnetic structure of pure and Fe 2+-doped single crystals of NiBr 2. Use of the multidetector permits detailed mapping of satellite intensity around 003 M arising from three magnetic domains, from which the magnitude and direction of the helix propagation vector τ are deduced. τ moves from [110] (0.0138(5) Å -1) in NiBr 2 to [100] (0.0151(5) Å -1) in Ni 0.91 Fe 0.09Br 2. The measured intensity profiles in (2θ, ω, v space are fitted to model profiles constructed by superimposing profiles measured at 003 M in the collinear phase at 28 K on a ring with radius τ, and optimizing the weighting of intensity around the ring.

  10. Bubbling bed catalytic hydropyrolysis process utilizing larger catalyst particles and smaller biomass particles featuring an anti-slugging reactor

    SciTech Connect

    Marker, Terry L; Felix, Larry G; Linck, Martin B; Roberts, Michael J

    2014-09-23

    This invention relates to a process for thermochemically transforming biomass or other oxygenated feedstocks into high quality liquid hydrocarbon fuels. In particular, a catalytic hydropyrolysis reactor, containing a deep bed of fluidized catalyst particles is utilized to accept particles of biomass or other oxygenated feedstocks that are significantly smaller than the particles of catalyst in the fluidized bed. The reactor features an insert or other structure disposed within the reactor vessel that inhibits slugging of the bed and thereby minimizes attrition of the catalyst. Within the bed, the biomass feedstock is converted into a vapor-phase product, containing hydrocarbon molecules and other process vapors, and an entrained solid char product, which is separated from the vapor stream after the vapor stream has been exhausted from the top of the reactor. When the product vapor stream is cooled to ambient temperatures, a significant proportion of the hydrocarbons in the product vapor stream can be recovered as a liquid stream of hydrophobic hydrocarbons, with properties consistent with those of gasoline, kerosene, and diesel fuel. Separate streams of gasoline, kerosene, and diesel fuel may also be obtained, either via selective condensation of each type of fuel, or via later distillation of the combined hydrocarbon liquid.

  11. Remediation of Water Contaminated with an Azo Dye: An Undergraduate Laboratory Experiment Utilizing an Inexpensive Photocatalytic Reactor

    NASA Astrophysics Data System (ADS)

    Bumpus, John A.; Tricker, Jennifer; Andrzejewski, Ken; Rhoads, Heather; Tatarko, Matthew

    1999-12-01

    The construction and use of an inexpensive photocatalytic reactor that utilizes titanium dioxide as the photocatalyst for wastewater treatment is described. In these experiments and in supplementary material, students are made aware that a variety of techniques have been developed to treat wastewaters, including those generated by the chemical industry. Water contaminated with the azo dye Congo Red was selected as an example of how one might treat contaminated water from a textile manufacturing facility. These experiments emphasize that, in addition to product development, chemists must also be concerned with waste treatment. A summary of the theory of titanium dioxide-mediated photocatalysis is provided. The phenomenon of photosensitization is also discussed. The usefulness of Congo Red is summarized and a brief history of this dye is given. In addition to being inexpensive, the photocatalytic reactor described is easy to construct and uses a readily available low-wattage fluorescent light. An important feature of this reactor is that the heat generated by the light source is readily dissipated by the water undergoing treatment. Thus no special cooling apparatus is required. One of the most important aspects of this work is that it provides a wide variety of continuing research suggestions that would be suitable and readily accomplished in undergraduate departments and high school laboratories; even those where budgetary priorities are a major concern. Use of this reactor would also enable students to design systems to treat "real-world" wastes, including some that are generated in instructional laboratories.

  12. Utilization of non-weapons-grade plutonium and highly enriched uranium with breeding of the 233U isotope in the VVER reactors using thorium and heavy water

    NASA Astrophysics Data System (ADS)

    Marshalkin, V. E.; Povyshev, V. M.

    2015-12-01

    A method for joint utilization of non-weapons-grade plutonium and highly enriched uranium in the thorium-uranium—plutonium oxide fuel of a water-moderated reactor with a varying water composition (D2O, H2O) is proposed. The method is characterized by efficient breeding of the 233U isotope and safe reactor operation and is comparatively simple to implement.

  13. Utilizing a Russian space nuclear reactor for a United States space mission: Systems integration issues

    SciTech Connect

    Reynolds, E.; Schaefer, E.; Polansky, G.; Lacy, J.; Bocharov, A.

    1993-09-30

    The Nuclear Electric Propulsion Space Test Program (NEPSTP) has developed a cooperative relationship with several institutes of the former Soviet Union to evaluate Russian space hardware on a US spacecraft One component is the Topaz II Nuclear Power System; a built and flight qualified nuclear reactor that has yet to be tested in space. The access to the Topaz II reactor provides the NEPSTP with a rare opportunity; to conduct an early flight demonstration of nuclear electric propulsion at a relatively low cost. This opportunity, however, is not without challenges. Topaz II was designed to be compatible with Russian spacecraft and launch vehicles. It was manufactured and flight qualified by Russian techniques and standards and conforms to safety requirements of the former Soviet Union, not the United States. As it is desired to make minimal modifications to the Topaz II, integrating the reactor system with a United States spacecraft and launch vehicle presents an engineering challenge. This paper documents the lessons teamed regarding the integration of reactor based spacecraft and also some insight about integrating Russian hardware. It examines the planned integration flow along with specific reactor requirements that affect the spacecraft integration including American-Russian space system compatibility.

  14. The role of MgBr2 to enhance the ionic conductivity of PVA/PEDOT:PSS polymer composite

    PubMed Central

    Sheha, Eslam M.; Nasr, Mona M.; El-Mansy, Mabrouk K.

    2014-01-01

    A solid polymer electrolyte system based on poly(vinyl alcohol) (PVA) and poly(3,4-Etylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) complexed with magnesium bromide (MgBr2) salt was prepared using solution cast technique. The ionic conductivity is observed to increase with increasing MgBr2 concentration. The maximum conductivity was found to be 9.89 × 10−6 S/cm for optimum polymer composite film (30 wt.% MgBr2) at room temperature. The increase in the conductivity is attributed to the increase in the number of ions as the salt concentration is increased. This has been proven by dielectric studies. The increase in conductivity is also attributable to the increase in the fraction of amorphous region in the electrolyte films as confirmed by their structural, thermal, electrical and optical properties. PMID:26199746

  15. Infrared fluorescence studies of electronic-to-vibrational energy transfer in a Br2:NO system. Master's thesis

    SciTech Connect

    Hawks, M.R.

    1993-12-01

    Steady-state photolysis techniques were used to study electronic-to-vibrational energy transfer mechanisms from atomic bromine to nitric oxide. Molecular bromine was photodissociated by 488nm radiation to produce equal parts Br(2p(sub 1/2)) and Br(2p (sub 3/2)). Side fluorescence intensity from Br(2p (sub 1/2)) at 2.7 microns and from NO (v =1) and 2 around 5.3 microns measured as a function of bromine pressure and nitric oxide pressure. The branching ratio collisional transfer into the first and second states of NO was determined, and previously reported rates for quenching of NO by molecular bromine were verified. Nitric oxide, Bromine, E-V transfer, Infrared fluorescence, Photolysis.

  16. Utilization of Heavy Metal Molten Salts in the ARIES-RS Fusion Reactor

    NASA Astrophysics Data System (ADS)

    Übeyli, Mustafa; Yapıcı, Hüseyin

    2008-09-01

    ARIES-RS is one of the major magnetic fusion energy reactor designs that uses a blanket having vanadium alloy structure cooled by lithium [1, 2]. It is a deuterium-tritium (DT) fusion driven reactor, having a fusion power of 2170 MW [1, 2]. This study presents the neutronic analysis of the ARIES-RS fusion reactor using heavy metal molten salts in which Li2BeF4 as the main constituent was mixed with increased mole fractions of heavy metal salt (ThF4 or UF4) starting by 2 mol.% up to 12 mol.%. Neutron transport calculations were carried out with the help of the SCALE 4.3 system by solving the Boltzmann transport equation with the XSDRNPM code in 238 neutron groups and a S 8- P 3 approximation. According to the numerical results, tritium self-sufficiency was attained for the coolants, Flibe with 2% UF4 or ThF4 and 4% UF4. In addition, higher energy multiplication values were found for the salt with UF4 compared to that with ThF4. Furthermore, significant amount of high quality nuclear fuel was produced to be used in external reactors.

  17. Utilization of cobalt catalyst for high temperature Fischer-Tropsch synthesis in a fluidized bed reactor

    NASA Astrophysics Data System (ADS)

    Mabry, James C.

    The research determined that the improved heat transfer characteristics of a fluidized bed reactor (FBR) will allow the use of cobalt catalyst for high temperature Fischer-Tropsch synthesis (HTFT). Cobalt was loaded onto a gamma alumina support, the catalyst was characterized using TPR, BET/BJH, XRD, and PSA to track changes in the catalyst morphology. The reactor was characterized to determine the minimum fluidization velocity and the maximum velocity prior to entering lean phase fluidization with pneumatic transport of the catalyst. The highest minimum fluidization velocity was found to be about 2800 sccm, there was no maximum velocity found for the reactor setup. Once characterized, the reactor was operated at pressures of 145, 217.6, and 290.1 psig, a syngas flow rate of 4000 sccm, and at temperatures of 330 and 350 °C. The optimal conditions found in this study were 330 °C and 217 psig. At these conditions CO conversion was 83.53 % for a single pass. Methane, CO2, and light gases (C2 -- C4) selectivities were at low rates of 31.43, 5.80, and 3.48 % respectively. Alcohol selectivity at these conditions was non-existent. The olefin and wax selectivities were the lowest of the data set at 7.05 and 3.18 % respectively. Liquid transportation fuels selectivity was the highest at 56.11 %.

  18. Computational fluid dynamic simulations of chemical looping fuel reactors utilizing gaseous fuels

    SciTech Connect

    Mahalatkar, K.; Kuhlman, J.; Huckaby, E.D.; O'Brien, T.

    2011-01-01

    A computational fluid dynamic(CFD) model for the fuel reactor of chemical looping combustion technology has been developed,withspecialfocusonaccuratelyrepresentingtheheterogeneous chemicalreactions.Acontinuumtwo-fluidmodelwasusedtodescribeboththegasandsolidphases. Detailedsub-modelstoaccountforfluid–particleandparticle–particleinteractionforceswerealso incorporated.Twoexperimentalcaseswereanalyzedinthisstudy(Son andKim,2006; Mattisonetal., 2001). SimulationswerecarriedouttotestthecapabilityoftheCFDmodeltocapturechangesinoutletgas concentrationswithchangesinnumberofparameterssuchassuperficialvelocity,metaloxide concentration,reactortemperature,etc.Fortheexperimentsof Mattissonetal.(2001), detailedtime varyingoutletconcentrationvalueswerecompared,anditwasfoundthatCFDsimulationsprovideda reasonablematchwiththisdata.

  19. Modelling of magnetic satellite intensity in the neutron diffraction of an incommensurate helical structure: NiBr 2 and Ni 0.9Fe 0.1Br 2

    NASA Astrophysics Data System (ADS)

    Day, P.; Moore, M. W.; Wilkinson, C.; Ziebeck, K. R. A.

    1986-02-01

    We describe the application of a neutron multidetector diffractometer (D16, ILL) to study the incommensurate helical magnetic structure of pure and Fe 2+ -doped single crystals of NiBr 2. Detailed mapping of satellite intensity around (0, 0, 3/2) yields the magnitude and direction of the helix propagation vector τ. τ moves from [110] in NiBr 2 to [100] in Ni 09Fe 0.1Br 2 with only a 5% increase in magnitude. The incommensurate-commensurate transition temperature is unchanged. The measured intensity profiles in (2ϑ, ω, v) space are fitted to model profiles constructed by superimposing profiles measured in the collinear phase at 28 K on a ring with radius τ, and optimizing the weighting of intensity around the ring. Based on the models optimized for these two crystals data from single detector instruments has been analysed for a range of Ni 1-xFe xBr 2 crystals and the magnetic phase diagram derived.

  20. Optimization of electrode characteristics for the Br-2/H-2 redox flow cell

    SciTech Connect

    Tucker, MC; Cho, KT; Weber, AZ; Lin, GY; Nguyen, TV

    2014-10-17

    The Br-2/H-2 redox flow cell shows promise as a high-power, low-cost energy storage device. The effect of various aspects of material selection, processing, and assembly of electrodes on the operation, performance, and efficiency of the system is determined. In particular, (+) electrode thickness, cell compression, hydrogen pressure, and (-) electrode architecture are investigated. Increasing hydrogen pressure and depositing the (-) catalyst layer on the membrane instead of on the carbon paper backing layers have a large positive impact on performance, enabling a limiting current density above 2 A cm(-2) and a peak power density of 1.4 W cm(-2). Maximum energy efficiency of 79 % is achieved. In addition, the root cause of limiting-current behavior in this system is elucidated, where it is found that Br- reversibly adsorbs at the Pt (-) electrode for potentials exceeding a critical value, and the extent of Br- coverage is potential-dependent. This phenomenon limits maximum cell current density and must be addressed in system modeling and design. These findings are expected to lower system cost and enable higher efficiency.

  1. A Kinetic Study of the Gas-Phase Reaction of OH with Br2

    PubMed Central

    Bryukov, Mikhail G.; Dellinger, Barry; Knyazev, Vadim D.

    2011-01-01

    An experimental, temperature-dependent kinetic study of the gas-phase reaction of the hydroxyl radical with molecular bromine (reaction 1) has been performed using a pulsed laser photolysis/pulsed-laser-induced fluorescence technique over a wide temperature range of 297 – 766 K, and at pressures between 6.68 and 40.29 kPa of helium. The experimental rate coefficients for reaction 1 demonstrate no correlation with pressure and exhibit a negative temperature dependence with a slight negative curvature in the Arrhenius plot. A non-linear least-squares fit with two floating parameters of the temperature dependent k1(T) data set using an equation of the form k1(T) = ATn yields the recommended expression k1(T) = 1.85×10−9T − 0.66 cm3 molecule−1 s−1 for the temperature dependence of the reaction 1 rate coefficient. The potential energy surface (PES) of reaction 1 was investigated using quantum chemistry methods. The reaction proceeds through formation of a weakly bound OH···Br2 complex and a PES saddle point with an energy below that of the reactants. Temperature dependence of the reaction rate coefficient was modeled using the RRKM method on the basis of the calculated PES. PMID:16854030

  2. Molten salt rolling bubble column, reactors utilizing same and related methods

    SciTech Connect

    Turner, Terry D.; Benefiel, Bradley C.; Bingham, Dennis N.; Klinger, Kerry M.; Wilding, Bruce M.

    2015-11-17

    Reactors for carrying out a chemical reaction, as well as related components, systems and methods are provided. In accordance with one embodiment, a reactor is provided that includes a furnace and a crucible positioned for heating by the furnace. The crucible may contain a molten salt bath. A downtube is disposed at least partially within the interior crucible along an axis. The downtube includes a conduit having a first end in communication with a carbon source and an outlet at a second end of the conduit for introducing the carbon material into the crucible. At least one opening is formed in the conduit between the first end and the second end to enable circulation of reaction components contained within the crucible through the conduit. An oxidizing material may be introduced through a bottom portion of the crucible in the form of gas bubbles to react with the other materials.

  3. Electrically heated ex-reactor pellet-cladding interaction (PCI) simulations utilizing irradiated Zircaloy cladding. [PWR

    SciTech Connect

    Barner, J.O.; Fitzsimmons, D.E.

    1985-02-01

    In a program sponsored by the Fuel Systems Research Branch of the US Nuclear Regulatory Commission, a series of six electrically heated fuel rod simulation tests were conducted at Pacific Northwest Laboratory. The primary objective of these tests was to determine the susceptibility of irradiated pressurized-water reactor (PWR) Zircaloy-4 cladding to failures caused by pellet-cladding mechanical interaction (PCMI). A secondary objective was to acquire kinetic data (e.g., ridge growth or relaxation rates) that might be helpful in the interpretation of in-reactor performance results and/or the modeling of PCMI. No cladding failures attributable to PCMI occurred during the six tests. This report describes the testing methods, testing apparatus, fuel rod diametral strain-measuring device, and test matrix. Test results are presented and discussed.

  4. Lunar electric power systems utilizing the SP-100 reactor coupled to dynamic conversion systems

    NASA Astrophysics Data System (ADS)

    Harty, Richard B.; Durand, Richard E.; Mason, Lee S.

    1991-09-01

    An integration study was performed by coupling an SP-100 reactor to either a Brayton or Stirling power conversion subsystem. The application was for a surface power system to supply power requirements to a lunar base. A power level of 550 kWe was selected based on the NASA Space Exploration Initiative 90-day study. Reliability studies were initially performed to determine optimum power-conversion redundancy. This study resulted in selecting three operating engines and one standby unit. Integratiaon-design studies indicated that either the Brayton or Stirling power conversion subsystem could be integrated with the SP-100 reactor. The Stirling system had an integration advantage because of smaller piping size and fewer components. The Stirling engine, however, is more complex and heavier than the Brayton rotating unit, which tends to offset the Stirling integration advantage. From a performance consideration, the Brayton had a 9-percent mass advantage and the Stirling a 50-percent radiator-area advantage.

  5. A Compact Torus Fusion Reactor Utilizing a Continuously Generated String of CT's. The CT String Reactor, CTSR

    NASA Astrophysics Data System (ADS)

    Hartman, Charles W.; Reisman, David B.; McLean, Harry S.; Thomas, John

    2008-06-01

    A fusion reactor is described in which a moving string of mutually repelling compact toruses (alternating helicity, unidirectional Btheta) is generated by repetitive injection using a magnetized coaxial gun driven by continuous gun current with alternating poloidal field. An injected CT relaxes to a minimum magnetic energy equilibrium, moves into a compression cone, and enters a conducting cylinder where the plasma is heated to fusion-producing temperature. The CT then passes into a blanketed region where fusion energy is produced and, on emergence from the fusion region, the CT undergoes controlled expansion in an exit cone where an alternating poloidal field opens the flux surfaces to directly recover the CT magnetic energy as current which is returned to the formation gun. The CT String Reactor (CTSTR) reactor satisfies all the necessary MHD stability requirements and is based on extrapolation of experimentally achieved formation, stability, and plasma confinement. It is supported by extensive 2D, MHD calculations. CTSTR employs minimal external fields supplied by normal conductors, and can produce high fusion power density with uniform wall loading. The geometric simplicity of CTSTR acts to minimize initial and maintenance costs, including periodic replacement of the reactor first wall. 60 /proj/ads/abstracts/absload/springerxml.pl* /proj/ads/abstracts/sources/SPRINGER/files/JOU=10894/VOL=2008.27/ISU=3/ART=9121: total 28 28 10894_2007_Article_9121.xml.meta /proj/ads/abstracts/sources/SPRINGER/files/JOU=10894/VOL=2008.27/ISU=3/ART=9122: total 16 16 10894_2007_Article_9122.xml.meta /proj/ads/abstracts/sources/SPRINGER/files/JOU=10894/VOL=2008.27/ISU=3/ART=9123: total 12 12 10894_2007_Article_9123.xml.meta /proj/ads/abstracts/sources/SPRINGER/files/JOU=10894/VOL=2008.27/ISU=3/ART=9124: total 36 36 10894_2007_Article_9124.xml.meta /proj/ads/abstracts/sources/SPRINGER/files/JOU=10894/VOL=2008.27/ISU=3/ART=9125: total 32 32 10894_2007_Article_9125.xml.meta /proj

  6. REACTOR

    DOEpatents

    Szilard, L.

    1963-09-10

    A breeder reactor is described, including a mass of fissionable material that is less than critical with respect to unmoderated neutrons and greater than critical with respect to neutrons of average energies substantially greater than thermal, a coolant selected from sodium or sodium--potassium alloys, a control liquid selected from lead or lead--bismuth alloys, and means for varying the quantity of control liquid in the reactor. (AEC)

  7. REACTOR

    DOEpatents

    Christy, R.F.

    1961-07-25

    A means is described for co-relating the essential physical requirements of a fission chain reaction in order that practical, compact, and easily controllable reactors can be built. These objects are obtained by employing a composition of fissionsble isotope and moderator in fluid form in which the amount of fissionsble isotcpe present governs the reaction. The size of the reactor is no longer a critical factor, the new criterion being the concentration of the fissionable isotope.

  8. The obesity-induced transcriptional regulator TRIP-Br2 mediates visceral fat endoplasmic reticulum stress-induced inflammation

    PubMed Central

    Qiang, Guifen; Kong, Hyerim Whang; Fang, Difeng; McCann, Maximilian; Yang, Xiuying; Du, Guanhua; Blüher, Matthias; Zhu, Jinfang; Liew, Chong Wee

    2016-01-01

    The intimate link between location of fat accumulation and metabolic disease risk and depot-specific differences is well established, but how these differences between depots are regulated at the molecular level remains largely unclear. Here we show that TRIP-Br2 mediates endoplasmic reticulum (ER) stress-induced inflammatory responses in visceral fat. Using in vitro, ex vivo and in vivo approaches, we demonstrate that obesity-induced circulating factors upregulate TRIP-Br2 specifically in visceral fat via the ER stress pathway. We find that ablation of TRIP-Br2 ameliorates both chemical and physiological ER stress-induced inflammatory and acute phase response in adipocytes, leading to lower circulating levels of inflammatory cytokines. Using promoter assays, as well as molecular and pharmacological experiments, we show that the transcription factor GATA3 is responsible for the ER stress-induced TRIP-Br2 expression in visceral fat. Taken together, our study identifies molecular regulators of inflammatory response in visceral fat that—given that these pathways are conserved in humans—might serve as potential therapeutic targets in obesity. PMID:27109496

  9. The obesity-induced transcriptional regulator TRIP-Br2 mediates visceral fat endoplasmic reticulum stress-induced inflammation.

    PubMed

    Qiang, Guifen; Kong, Hyerim Whang; Fang, Difeng; McCann, Maximilian; Yang, Xiuying; Du, Guanhua; Blüher, Matthias; Zhu, Jinfang; Liew, Chong Wee

    2016-01-01

    The intimate link between location of fat accumulation and metabolic disease risk and depot-specific differences is well established, but how these differences between depots are regulated at the molecular level remains largely unclear. Here we show that TRIP-Br2 mediates endoplasmic reticulum (ER) stress-induced inflammatory responses in visceral fat. Using in vitro, ex vivo and in vivo approaches, we demonstrate that obesity-induced circulating factors upregulate TRIP-Br2 specifically in visceral fat via the ER stress pathway. We find that ablation of TRIP-Br2 ameliorates both chemical and physiological ER stress-induced inflammatory and acute phase response in adipocytes, leading to lower circulating levels of inflammatory cytokines. Using promoter assays, as well as molecular and pharmacological experiments, we show that the transcription factor GATA3 is responsible for the ER stress-induced TRIP-Br2 expression in visceral fat. Taken together, our study identifies molecular regulators of inflammatory response in visceral fat that-given that these pathways are conserved in humans-might serve as potential therapeutic targets in obesity. PMID:27109496

  10. REACTOR

    DOEpatents

    Roman, W.G.

    1961-06-27

    A pressurized water reactor in which automatic control is achieved by varying the average density of the liquid moderator-cooiant is patented. Density is controlled by the temperature and power level of the reactor ftself. This control can be effected by the use of either plate, pellet, or tubular fuel elements. The fuel elements are disposed between upper and lower coolant plenum chambers and are designed to permit unrestricted coolant flow. The control chamber has an inlet opening communicating with the lower coolant plenum chamber and a restricted vapor vent communicating with the upper coolant plenum chamber. Thus, a variation in temperature of the fuel elements will cause a variation in the average moderator density in the chamber which directly affects the power level of the reactor.

  11. Lunar electric power systems utilizing the SP-100 reactor coupled to dynamic conversion systems

    NASA Astrophysics Data System (ADS)

    Harty, Richard B.; Durand, Richard E.

    1993-03-01

    An integration study was performed by Rocketdyne under contract to NASA-LeRC. The study was concerned with coupling an SP-0100 reactor to either a Brayton or Stirling power conversion system. The application was for a surface power system to supply power requirements to a lunar base. A power level of 550 kWe was selected based on the NASA Space Exploration Initiative 90-day study. Reliability studies were initially performed to determine optimum power conversion redundancy. This study resulted in selecting three operating engines and one stand-by unit. Integration design studies indicated that either the Brayton or Stirling power conversion systems could be integrated with the PS-100 reactor. The Stirling system had an integration advantage because of smaller piping size and fewer components. The Stirling engine, however, is more complex and heavier than the Brayton rotating unit, which tends to off-set the Stirling integration advantage. From a performance consideration, the Brayton had a 9 percent mass advantage, and the Stirling had a 50 percent radiator advantage.

  12. Utilization of experimental integral data for the adjustment and uncertainty evaluation of reactor design quantities

    SciTech Connect

    Poenitz, W.P.; Collins, P.J.

    1988-01-01

    Biases and uncertainties of calculated reactor design quantities caused by errors and uncertainties of basic parameters, such as neutron cross sections, fission spectra parameters, and prompt and delayed neutron yields, are large, and in most cases, exceed reactor design requirements. Errors and uncertainties due to models and methods approximations contribute as well. An extensive data base, with presently /approximately/300 experimental integral values from 28 critical assemblies, has been assembled at Argonne National Laboratory in order to provide improvements and to investigate both sources of uncertainties. Generalized-least-squares fitting is being used. The available large data base permitted the investigation of the influence of specific input data, the constraints of the covariance information, the selection of parameters, and the reliability of the predictions. It is shown that reliable improvements of calculated quantities like enrichment, breeding ratio, sodium void, control rod worth, power distribution, and material worth can be made. Substantial reductions of the uncertainties of these quantities, which are caused by the uncertainties of the basic parameters, are obtained in most cases. The FFTF uranium-metal-core conversion is the first application of the present effort. 21 refs., 2 figs., 10 tabs.

  13. Lunar electric power systems utilizing the SP-100 reactor coupled to dynamic conversion systems. Final report

    SciTech Connect

    Harty, R.B.; Durand, R.E.

    1993-03-01

    An integration study was performed by Rocketdyne under contract to NASA-LeRC. The study was concerned with coupling an SP-0100 reactor to either a Brayton or Stirling power conversion system. The application was for a surface power system to supply power requirements to a lunar base. A power level of 550 kWe was selected based on the NASA Space Exploration Initiative 90-day study. Reliability studies were initially performed to determine optimum power conversion redundancy. This study resulted in selecting three operating engines and one stand-by unit. Integration design studies indicated that either the Brayton or Stirling power conversion systems could be integrated with the PS-100 reactor. The Stirling system had an integration advantage because of smaller piping size and fewer components. The Stirling engine, however, is more complex and heavier than the Brayton rotating unit, which tends to off-set the Stirling integration advantage. From a performance consideration, the Brayton had a 9 percent mass advantage, and the Stirling had a 50 percent radiator advantage.

  14. Lunar electric power systems utilizing the SP-100 reactor coupled to dynamic conversion systems

    NASA Technical Reports Server (NTRS)

    Harty, Richard B.; Durand, Richard E.

    1993-01-01

    An integration study was performed by Rocketdyne under contract to NASA-LeRC. The study was concerned with coupling an SP-0100 reactor to either a Brayton or Stirling power conversion system. The application was for a surface power system to supply power requirements to a lunar base. A power level of 550 kWe was selected based on the NASA Space Exploration Initiative 90-day study. Reliability studies were initially performed to determine optimum power conversion redundancy. This study resulted in selecting three operating engines and one stand-by unit. Integration design studies indicated that either the Brayton or Stirling power conversion systems could be integrated with the PS-100 reactor. The Stirling system had an integration advantage because of smaller piping size and fewer components. The Stirling engine, however, is more complex and heavier than the Brayton rotating unit, which tends to off-set the Stirling integration advantage. From a performance consideration, the Brayton had a 9 percent mass advantage, and the Stirling had a 50 percent radiator advantage.

  15. REACTORS

    DOEpatents

    Spitzer, L. Jr.

    1961-10-01

    Thermonuclear reactors, methods, and apparatus are described for controlling and confining high temperature plasma. Main axial confining coils in combination with helical windings provide a rotational transform that avoids the necessity of a figure-eight shaped reactor tube. The helical windings provide a multipolar helical magnetic field transverse to the axis of the main axial confining coils so as to improve the effectiveness of the confining field by counteracting the tendency of the more central lines of force in the stellarator tube to exchange positions with the magnetic lines of force nearer the walls of the tube. (AEC)

  16. Utilization of non-weapons-grade plutonium and highly enriched uranium with breeding of the {sup 233}U isotope in the VVER reactors using thorium and heavy water

    SciTech Connect

    Marshalkin, V. E. Povyshev, V. M.

    2015-12-15

    A method for joint utilization of non-weapons-grade plutonium and highly enriched uranium in the thorium–uranium—plutonium oxide fuel of a water-moderated reactor with a varying water composition (D{sub 2}O, H{sub 2}O) is proposed. The method is characterized by efficient breeding of the {sup 233}U isotope and safe reactor operation and is comparatively simple to implement.

  17. Effective utilization of flue gases in raceway reactor with event-based pH control for microalgae culture.

    PubMed

    Pawlowski, A; Mendoza, J L; Guzmán, J L; Berenguel, M; Acién, F G; Dormido, S

    2014-10-01

    This work addresses effective utilization of flue gases through the proper pH control in raceway reactors. The pH control problem has been addressed with an event-based control approach using a Generalized Predictive Controller (GPC) with actuator deadband. Applying this control strategy it is possible to reduce the control effort, and at the same time saving control resources. In the pH process case, the event-based controller with actuator deadband can be tuned to supply only necessary amount of CO2 to keep the pH close to its optimal value. On the other hand, the evaluated control algorithm significantly improves the pH control accuracy, what has a direct influence on biomass production. In order to test the performance of the event-based GPC controller, several experiments have been performed on a real raceway reactor. Additionally, several control performance indexes have been used to compare the analyzed technique with commonly used on/off controller. PMID:25113401

  18. Final Report on Utilization of TRU TRISO Fuel as Applied to HTR Systems Part I: Pebble Bed Reactors

    SciTech Connect

    Brian Boer; Abderrafi M. Ougouag

    2011-03-01

    significant failure is to be expected for the reference fuel particle during normal operation. It was found, however, that the sensitivity of the coating stress to the CO production in the kernel was large. The CO production is expected to be higher in DB fuel than in UO2 fuel, but its exact level has a high uncertainty. Furthermore, in the fuel performance analysis transient conditions were not yet taken into account. The effort of this task in FY 2010 has focused on the optimization of the core to maximize the pebble discharge burnup level, while retaining its inherent safety characteristics. Using generic pebble bed reactor cores, this task will perform physics calculations to evaluate the capabilities of the pebble bed reactor to perform utilization and destruction of LWR used-fuel transuranics. The task will use established benchmarked models, and will introduce modeling advancements appropriate to the nature of the fuel considered (high transuranic [TRU] content and high burn-up). Accomplishments of this work include: •Core analysis of a HTR-MODULE design loaded with Deep-Burn fuel. •Core analysis of a HTR-MODULE design loaded with Deep-Burn fuel and Uranium. •Core analysis of a HTR-MODULE design loaded with Deep-Burn fuel and Modified Open Cycle Components. •Core analysis of a HTR-MODULE design loaded with Deep-Burn fuel and Americium targets.

  19. REACTOR

    DOEpatents

    Spitzer, L. Jr.

    1962-01-01

    The system conteraplates ohmically heating a gas to high temperatures such as are useful in thermonuclear reactors of the stellarator class. To this end the gas is ionized and an electric current is applied to the ionized gas ohmically to heat the gas while the ionized gas is confined to a central portion of a reaction chamber. Additionally, means are provided for pumping impurities from the gas and for further heating the gas. (AEC)

  20. The effects of CaCl2 and CaBr2 on the reproduction of Daphnia magna Straus.

    PubMed

    Mažuran, Neda; Hršak, Vladimir; Kovačević, Goran

    2015-06-01

    Concentrated CaCl2 and CaBr2 salt solutions of densities up to 2.3 kg L-1 are regularly used to control hydrostatic pressure in oil wells during special operations in the exploration and production of natural gas and crude oil. Various concentrations of high density salts are frequently left in mud pits near the drilling site as waste, polluting fresh and ground waters by spillage and drainage. The toxic effects of these salts have already been observed. This study investigated the effects of CaCl2 and CaBr2 on water flea Daphnia magna Straus in a 21-day reproduction test. The three tested concentrations of CaCl2 (240, 481, and 1925 mg L-1) caused a significant dose-response decrease of reproduction (p<0.001). With CaBr2 (533 and 1066 mg L-1), only aborted eggs were produced, demonstrating the embryotoxicity of the substance. The results suggest that high concentrations of the tested chemicals are harmful to Daphnia's reproduction and could reduce its abundance. PMID:26110475

  1. Integrated Water Gas Shift Membrane Reactors Utilizing Novel, Non Precious Metal Mixed Matrix Membrane

    SciTech Connect

    Ferraris, John

    2013-09-30

    Nanoparticles of zeolitic imidazolate frameworks and other related hybrid materials were prepared by modifying published synthesis procedures by introducing bases, changing stoichiometric ratios, or adjusting reaction conditions. These materials were stable at temperatures >300 °C and were compatible with the polymer matrices used to prepare mixed- matrix membranes (MMMs). MMMs tested at 300 °C exhibited a >30 fold increase in permeability, compared to those measured at 35 °C, while maintaining H{sub 2}/CO{sub 2} selectivity. Measurements at high pressure (up to 30 atm) and high temperature (up to 300 °C) resulted in an increase in gas flux across the membrane with retention of selectivity. No variations in permeability were observed at high pressures at either 35 or 300 °C. CO{sub 2}-induced plasticization was not observed for Matrimid®, VTEC, and PBI polymers or their MMMs at 30 atm and 300 °C. Membrane surface modification by cross-linking with ethanol diamine resulted in an increase in H{sub 2}/CO{sub 2} selectivity at 35 °C. Spectrometric analysis showed that the cross-linking was effective to temperatures <150 °C. At higher temperatures, the cross-linked membranes exhibit a H{sub 2}/CO{sub 2} selectivity similar to the uncross-linked polymer. Performance of the polybenzimidazole (PBI) hollow fibers prepared at Santa Fe Science and Technology (SFST, Inc.) showed increased flux o to a flat PBI membrane. A water-gas shift reactor has been built and currently being optimized for testing under DOE conditions.

  2. Theoretical studies on photoelectron and IR spectral properties of Br2.-(H2O)n clusters.

    PubMed

    Pathak, A K; Mukherjee, T; Maity, D K

    2007-07-28

    We report vertical detachment energy (VDE) and IR spectra of Br2.-.(H2O)n clusters (n=1-8) based on first principles electronic structure calculations. Cluster structures and IR spectra are calculated at Becke's half-and-half hybrid exchange-correlation functional (BHHLYP) with a triple split valence basis function, 6-311++G(d,p). VDE for the hydrated clusters is calculated based on second order Moller-Plesset perturbation (MP2) theory with the same set of basis function. On full geometry optimization, it is observed that conformers having interwater hydrogen bonding among solvent water molecules are more stable than the structures having double or single hydrogen bonded structures between the anionic solute, Br2.-, and solvent water molecules. Moreover, a conformer having cyclic interwater hydrogen bonded network is predicted to be more stable for each size hydrated cluster. It is also noticed that up to four solvent H2O units can reside around the solute in a cyclic interwater hydrogen bonded network. The excess electron in these hydrated clusters is localized over the solute atoms. Weighted average VDE is calculated for each size (n) cluster based on statistical population of the conformers at 150 K. A linear relationship is obtained for VDE versus (n+3)(-1/3) and bulk VDE of Br2.- aqueous solution is calculated as 10.01 eV at MP2 level of theory. BHHLYP density functional is seen to make a systematic overestimation in VDE values by approximately 0.5 eV compared to MP2 data in all the hydrated clusters. It is observed that hydration increases VDE of bromine dimer anion system by approximately 6.4 eV. Calculated IR spectra show that the formation of Br2.--water clusters induces large shifts from the normal O-H stretching bands of isolated water keeping bending modes rather insensitive. Hydrated clusters, Br2.-.(H2O)n, show characteristic sharp features of O-H stretching bands of water in the small size clusters. PMID:17672687

  3. Finding the Missing Stratospheric Br(sub y): A Global Modeling Study of CHBr3 and CH2Br2

    NASA Technical Reports Server (NTRS)

    Liang, Q.; Stolarski, R. S.; Kawa, S. R.; Nielsen, J. E.; Douglass, A. R.; Rodriguez, J. M.; Blake, D. R.; Atlas, E. L.; Ott, L. E.

    2010-01-01

    Recent in situ and satellite measurements suggest a contribution of 5 pptv to stratospheric inorganic bromine from short-lived bromocarbons. We conduct a modeling study of the two most important short-lived bromocarbons, bromoform (CHBr3) and dibromomethane (CH2Br2), with the Goddard Earth Observing System Chemistry Climate Model (GEOS CCM) to account for this missing stratospheric bromine. We derive a "top-down" emission estimate of CHBr3 and CH2Br2 using airborne measurements in the Pacific and North American troposphere and lower stratosphere obtained during previous NASA aircraft campaigns. Our emission estimate suggests that to reproduce the observed concentrations in the free troposphere, a global oceanic emission of 425 Gg Br yr(exp -1) for CHBr3 and 57 Gg Br yr(exp -l) for CH2Br2 is needed, with 60% of emissions from open ocean and 40% from coastal regions. Although our simple emission scheme assumes no seasonal variations, the model reproduces the observed seasonal variations of the short-lived bromocarbons with high concentrations in winter and low concentrations in summer. This indicates that the seasonality of short-lived bromocarbons is largely due to seasonality in their chemical loss and transport. The inclusion of CHBr3 and CH2Br2 contributes 5 pptv bromine throughout the stratosphere. Both the source gases and inorganic bromine produced from source gas degradation (BrSLS) in the troposphere are transported into the stratosphere, and are equally important. Inorganic bromine accounts for half (2.5 pptv) of the bromine from the inclusion of CHBr3 and CHzBr2 near the tropical tropopause and its contribution rapidly increases to 100% as altitude increases. More than 85% of the wet scavenging of Br(sub y)(sup VSLS) occurs in large-scale precipitation below 500 hPa. Our sensitivity study with wet scavenging in convective updrafts switched off suggests that Br(sub y)(sup SLS) in the stratosphere is not sensitive to convection. Convective scavenging only

  4. Gas utilization in TFTR (Tokamak Fusion Test Reactor) neutral beam injectors

    SciTech Connect

    Kamperschroer, J.H.; Gammel, G.M.; Kugel, H.W.; Grisham, L.R.; Stevenson, T.N.; von Halle, A.; Williams, M.D.

    1987-08-01

    Measurements of gas utilization in a test TFTR neutral beam injector have been performed to study the feasibility of running tritium neutral beams with existing ion sources. Gas consumption is limited by the restriction of 50,000 curies of T/sub 2/ allowed on site. It was found that the gas efficiency of the present long-pulse ion sources is higher than it was with previous short-pulse sources. Gas efficiencies were studied over the range of 35 to 55%. At the high end of this range the neutral fraction of the beam fell below that predicted by room temperature molecular gas flow. This is consistent with observations made on the JET injectors, where it has been attributed to beam heating of the neutralizer gas and a concomitant increase in conductance. It was found that a working gas isotope exchange from H/sub 2/ to D/sub 2/ could be accomplished on the first beam shot after changing the gas supply, without any intermediate preconditioning. The mechanism believed responsible for this phenomenon is heating of the plasma generator walls by the arc and a resulting thermal desorption of all previously adsorbed and implanted gas. Finally, it was observed that an ion source conditioned to 120 kV operation could produce a beam pulse after a waiting period of fourteen hours by preceding the beam extraction with several hi-pot/filament warm-up pulses, without any gas consumption. 18 refs., 7 figs., 2 tabs.

  5. A Cancer Specific Cell-Penetrating Peptide, BR2, for the Efficient Delivery of an scFv into Cancer Cells

    PubMed Central

    Lim, Ki Jung; Sung, Bong Hyun; Shin, Ju Ri; Lee, Young Woong; Kim, Da Jung; Yang, Kyung Seok; Kim, Sun Chang

    2013-01-01

    Cell-penetrating peptides (CPPs) have proven very effective as intracellular delivery vehicles for various therapeutics. However, there are some concerns about non-specific penetration and cytotoxicity of CPPs for effective cancer treatments. Herein, based on the cell-penetrating motif of an anticancer peptide, buforin IIb, we designed several CPP derivatives with cancer cell specificity. Among the derivatives, a 17-amino acid peptide (BR2) was found to have cancer-specificity without toxicity to normal cells. After specifically targeting cancer cells through interaction with gangliosides, BR2 entered cells via lipid-mediated macropinocytosis. Moreover, BR2 showed higher membrane translocation efficiency than the well-known CPP Tat (49–57). The capability of BR2 as a cancer-specific drug carrier was demonstrated by fusion of BR2 to a single-chain variable fragment (scFv) directed toward a mutated K-ras (G12V). BR2-fused scFv induced a higher degree of apoptosis than Tat-fused scFv in K-ras mutated HCT116 cells. These results suggest that the novel cell-penetrating peptide BR2 has great potential as a useful drug delivery carrier with cancer cell specificity. PMID:23776609

  6. Reactor

    DOEpatents

    Evans, Robert M.

    1976-10-05

    1. A neutronic reactor having a moderator, coolant tubes traversing the moderator from an inlet end to an outlet end, bodies of material fissionable by neutrons of thermal energy disposed within the coolant tubes, and means for circulating water through said coolant tubes characterized by the improved construction wherein the coolant tubes are constructed of aluminum having an outer diameter of 1.729 inches and a wall thickness of 0.059 inch, and the means for circulating a liquid coolant through the tubes includes a source of water at a pressure of approximately 350 pounds per square inch connected to the inlet end of the tubes, and said construction including a pressure reducing orifice disposed at the inlet ends of the tubes reducing the pressure of the water by approximately 150 pounds per square inch.

  7. The origin of the conductivity maximum in molten salts. II. SnCl2 and HgBr2.

    PubMed

    Aravindakshan, Nikhil P; Kuntz, Colin M; Gemmell, Kyle E; Johnson, Keith E; East, Allan L L

    2016-09-01

    The phenomenon of electrical conductivity maxima of molten salts versus temperature during orthobaric (closed-vessel) conditions is further examined via ab initio simulations. Previously, in a study of molten BiCl3, a new theory was offered in which the conductivity falloff at high temperatures is due not to traditional ion association, but to a rise in the activation energy for atomic ions hopping from counterion to counterion. Here this theory is further tested on two more inorganic melts which exhibit conductivity maxima: another high-conducting melt (SnCl2, σmax = 2.81 Ω(-1) cm(-1)) and a low-conducting one (HgBr2, σmax = 4.06 × 10(-4) Ω(-1) cm(-1)). First, ab initio molecular dynamics simulations were performed and again appear successful in reproducing the maxima for both these liquids. Second, analysis of the simulated liquid structure (radial distributions, species concentrations) was performed. In the HgBr2 case, a very molecular liquid like water, a clear Grotthuss chain of bromide transfers was observed in simulation when seeding the system with a HgBr(+) cation and HgBr3 (-) anion. The first conclusion is that the hopping mechanism offered for molten BiCl3 is simply the Grotthuss mechanism for conduction, applicable not just to H(+) ions, but also to halide ions in post-transition-metal halide melts. Second, it is conjectured that the conductivity maximum is due to rising activation energy in network-covalent (halide-bridging) melts (BiCl3, SnCl2, PbCl2), but possibly a falling Arrhenius prefactor (collision frequency) for molecular melts (HgBr2). PMID:27609001

  8. Laser induced fluorescence (LIF) of Hg2 and Hg3 via dissociation of HgBr2 at 157 nm

    NASA Astrophysics Data System (ADS)

    Skordoulis, C.; Sarantopoulou, E.; Spyrou, S. M.; Kosmidis, C.; Cefalas, A. C.

    1991-06-01

    Laser induced fluorescence of the mercury clusters Hg2 and Hg3 in the spectral range between 300 nm to 510 nm has been obtained from the dissociation of HgBr2 at 7.88 eV (157.5 nm) with an F2 molecular laser, together with fluorescence from mercury atomic transitions from highly excited states. The excitation process involves two photon absorption which dissociates the molecule at 15.76 eV total photon energy with the subsequent formation of the metallic clusters.

  9. An investigation on the structure, spectroscopy and thermodynamic aspects of Br2((-))(H2O)n clusters using a conjunction of stochastic and quantum chemical methods.

    PubMed

    Naskar, Pulak; Chaudhury, Pinaki

    2016-06-28

    In this work we obtained global as well as local structures of Br2((-))(H2O)n clusters for n = 2 to 6 followed by the study of IR-spectral features and thermochemistry for the structures. The way adopted by us to obtain structures is not the conventional one used in most cases. Here we at first generated excellent quality pre-optimized structures by exploring the suitable empirical potential energy surface using stochastic optimizer simulated annealing. These structures are then further refined using quantum chemical calculations to obtain the final structures, and spectral and thermodynamic features. We clearly showed that our approach results in very quick and better convergence which reduces the computational cost and obviously using the strategy we are able to get one [i.e. global] or more than one [i.e. global and local(s)] energetically lower structures than those which are already reported for a given cluster size. Moreover, IR-spectral results and the evolutionary trends in interaction energy, solvation energy and vertical detachment energy for global structures of each size have also been presented to establish the utility of the procedure employed. PMID:27251059

  10. Impact of membrane characteristics on the performance and cycling of the Br2-H2 redox flow cell

    NASA Astrophysics Data System (ADS)

    Tucker, Michael C.; Cho, Kyu Taek; Spingler, Franz B.; Weber, Adam Z.; Lin, Guangyu

    2015-06-01

    The Br2/H2 redox flow cell shows promise as a high-power, low-cost energy storage device. In this paper, the effect of various aspects of material selection and processing of proton exchange membranes on the operation of the Br2/H2 redox flow cell is determined. Membrane properties have a significant impact on the performance and efficiency of the system. In particular, there is a tradeoff between conductivity and crossover, where conductivity limits system efficiency at high current density and crossover limits efficiency at low current density. The impact of thickness, pretreatment procedure, swelling state during cell assembly, equivalent weight, membrane reinforcement, and addition of a microporous separator layer on this tradeoff is assessed. NR212 (50 μm) pretreated by soaking in 70 °C water is found to be optimal for the studied operating conditions. For this case, an energy efficiency of greater than 75% is achieved for current density up to 400 mA cm-2, with a maximum obtainable energy efficiency of 88%. A cell with this membrane was cycled continuously for 3164 h. Membrane transport properties, including conductivity and bromine and water crossover, were found to decrease moderately upon cycling but remained higher than those for the as-received membrane.

  11. Impact of membrane characteristics on the performance and cycling of the Br-2-H-2 redox flow cell

    SciTech Connect

    Tucker, MC; Cho, KT; Spingler, FB; Weber, AZ; Lin, GY

    2015-06-15

    The Br-2/H-2 redox flow cell shows promise as a high-power, low-cost energy storage device. In this paper, the effect of various aspects of material selection and processing of proton exchange membranes on the operation of the Br-2/H-2 redox flow cell is determined. Membrane properties have a significant impact on the performance and efficiency of the system. In particular, there is a tradeoff between conductivity and crossover, where conductivity limits system efficiency at high current density and crossover limits efficiency at low current density. The impact of thickness, pretreatment procedure, swelling state during cell assembly, equivalent weight, membrane reinforcement, and addition of a microporous separator layer on this tradeoff is assessed. NR212 (50 mu m) pretreated by soaking in 70 degrees C water is found to be optimal for the studied operating conditions. For this case, an energy efficiency of greater than 75% is achieved for current density up to 400 mA cm(-2), with a maximum obtainable energy efficiency of 88%. A cell with this membrane was cycled continuously for 3164 h. Membrane transport properties, including conductivity and bromine and water crossover, were found to decrease moderately upon cycling but remained higher than those for the as-received membrane. (C) 2015 Elsevier B.V. All rights reserved.

  12. Molecular elimination of Br2 in photodissociation of CH2BrC(O)Br at 248 nm using cavity ring-down absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Fan, He; Tsai, Po-Yu; Lin, King-Chuen; Lin, Cheng-Wei; Yan, Chi-Yu; Yang, Shu-Wei; Chang, A. H. H.

    2012-12-01

    The primary elimination channel of bromine molecule in one-photon dissociation of CH2BrC(O)Br at 248 nm is investigated using cavity ring-down absorption spectroscopy. By means of spectral simulation, the ratio of nascent vibrational population in v = 0, 1, and 2 levels is evaluated to be 1:(0.5 ± 0.1):(0.2 ± 0.1), corresponding to a Boltzmann vibrational temperature of 581 ± 45 K. The quantum yield of the ground state Br2 elimination reaction is determined to be 0.24 ± 0.08. With the aid of ab initio potential energy calculations, the obtained Br2 fragments are anticipated to dissociate on the electronic ground state, yielding vibrationally hot Br2 products. The temperature-dependence measurements support the proposed pathway via internal conversion. For comparison, the Br2 yields are obtained analogously from CH3CHBrC(O)Br and (CH3)2CBrC(O)Br to be 0.03 and 0.06, respectively. The trend of Br2 yields among the three compounds is consistent with the branching ratio evaluation by Rice-Ramsperger-Kassel-Marcus method. However, the latter result for each molecule is smaller by an order of magnitude than the yield findings. A non-statistical pathway so-called roaming process might be an alternative to the Br2 production, and its contribution might account for the underestimate of the branching ratio calculations.

  13. Fuel swelling and interaction layer formation in the SELENIUM Si and ZrN coated U(Mo) dispersion fuel plates irradiated at high power in BR2

    NASA Astrophysics Data System (ADS)

    Leenaers, A.; Van den Berghe, S.; Koonen, E.; Kuzminov, V.; Detavernier, C.

    2015-03-01

    In the framework of the SELENIUM project two full size flat fuel plates were produced with respectively Si and ZrN coated U(Mo) particles and irradiated in the BR2 reactor at SCK•CEN. Non-destructive analysis of the plates showed that the fuel swelling profiles of both SELENIUM plates were very similar to each other and none of the plates showed signs of pillowing or excessive swelling at the end of irradiation at the highest power position (local maximum 70% 235U). The microstructural analysis showed that the Si coated fuel has less interaction phase formation at low burn-up but at the highest burn-ups, defects start to develop on the IL-matrix interface. The ZrN coated fuel, shows a virtual absence of reaction between the U(Mo) and the Al, up to high fission densities after which the interaction layer formation starts and defects develop in the matrix near the U(Mo) particles. It was found and is confirmed by the SELENIUM (Surface Engineering of Low ENrIched Uranium-Molybdenum) experiment that there are two phenomena at play that need to be controlled: the formation of an interaction layer and swelling of the fuel. As the interaction layer formation occurs at the U(Mo)-matrix interface, applying a diffusion barrier (coating) at that interface should prevent the interaction between U(Mo) and the matrix. The U(Mo) swelling, observed to proceed at an accelerating rate with respect to fission density accumulation, is governed by linear solid state swelling and fission gas bubble swelling due to recrystallization of the fuel. The examination of the SELENIUM fuel plates clearly show that for the U(Mo) dispersion fuel to be qualified, the swelling rate at high burn-up needs to be reduced.

  14. Preliminary Study on Utilization of Carbon Dioxide as a Coolant of High Temperature Engineering Test Reactor with MOX and Minor Actinides Fuel

    SciTech Connect

    Fauzia, A. F.; Waris, A.; Novitrian

    2010-06-22

    High temperature engineering test reactor (HTTR) is an uranium oxide (UO2) fuel, graphite moderator and helium gas-cooled reactor with 30 MW in thermal output and outlet coolant temperature of 950 deg. C. Instead of using helium gas, we have utilized carbon dioxide as a coolant in the present study. Beside that, uranium and plutonium oxide (mixed oxide, MOX) and minor actinides have been employed as a new fuel type of HTTR. Utilization of plutonium and minor actinide is one of the support system to non-proliferation issue in the nuclear development. The enrichment for uranium oxide has been varied of 6-20% with plutonium and minor actinides concentration of 10%. In this study, burnup period is 1100 days. The reactor cell calculation was performed by using SRAC 2002 code, with nuclear data library was derived from JENDL3.2. Reactor core calculation was done by using CITATION module. The result shows that HTTR can achieve its criticality condition with 14% of {sup 235}U enrichment.

  15. Preliminary Study on Utilization of Carbon Dioxide as a Coolant of High Temperature Engineering Test Reactor with MOX and Minor Actinides Fuel

    NASA Astrophysics Data System (ADS)

    Fauzia, A. F.; Waris, A.; Novitrian

    2010-06-01

    High temperature engineering test reactor (HTTR) is an uranium oxide (UO2) fuel, graphite moderator and helium gas-cooled reactor with 30 MW in thermal output and outlet coolant temperature of 950° C. Instead of using helium gas, we have utilized carbon dioxide as a coolant in the present study. Beside that, uranium and plutonium oxide (mixed oxide, MOX) and minor actinides have been employed as a new fuel type of HTTR. Utilization of plutonium and minor actinide is one of the support system to non-proliferation issue in the nuclear development. The enrichment for uranium oxide has been varied of 6-20% with plutonium and minor actinides concentration of 10%. In this study, burnup period is 1100 days. The reactor cell calculation was performed by using SRAC 2002 code, with nuclear data library was derived from JENDL3.2. Reactor core calculation was done by using CITATION module. The result shows that HTTR can achieve its criticality condition with 14% of 235 U enrichment.

  16. Pathways for the OH + Br2 → HOBr + Br and HOBr + Br → HBr + BrO Reactions.

    PubMed

    Wang, Hongyan; Qiu, Yudong; Schaefer, Henry F

    2016-02-11

    The OH radical reaction with Br2 and the subsequent reaction HOBr + Br are of exceptional importance to atmospheric chemistry and environmental chemistry. The entrance complex, transition state, and exit complex for both reactions have been determined using the coupled-cluster method with single, double, and perturbative triple excitations CCSD(T) with correlation consistent basis sets up to size cc-pV5Z and cc-pV5Z-PP. Coupled cluster effects with full triples (CCSDT) and full quadruples (CCSDTQ) are explicitly investigated. Scalar relativistic effects, spin-orbit coupling, and zero-point vibrational energy corrections are evaluated. The results from the all-electron basis sets are compared with those from the effective core potential (ECP) pseudopotential (PP) basis sets. The results are consistent. The OH + Br2 reaction is predicted to be exothermic 4.1 ± 0.5 kcal/mol, compared to experiment, 3.9 ± 0.2 kcal/mol. The entrance complex HO···BrBr is bound by 2.2 ± 0.2 kcal/mol. The transition state lies similarly well below the reactants OH + Br2. The exit complex HOBr···Br is bound by 2.7 ± 0.6 kcal/mol relative to separated HOBr + Br. The endothermicity of the reaction HOBr + Br → HBr + BrO is 9.6 ± 0.7 kcal/mol, compared with experiment 8.7 ± 0.3 kcal/mol. For the more important reverse (exothermic) HBr + BrO reaction, the entrance complex BrO···HBr is bound by 1.8 ± 0.6 kcal/mol. The barrier for the HBr + BrO reaction is 6.8 ± 0.9 kcal/mol. The exit complex (Br···HOBr) for the HBr + BrO reaction is bound by 1.9 ± 0.2 kcal/mol with respect to the products HOBr + Br. PMID:26766412

  17. NRC review of Electric Power Research Institute`s advanced light water reactor utility requirements document. Passive plant designs, chapter 1, project number 669

    SciTech Connect

    Not Available

    1994-08-01

    The Electric Power Research Institute (EPRI) is preparing a compendium of technical requirements, referred to as the {open_quotes}Advanced Light Water Reactor [ALWR] Utility Requirements Document{close_quotes}, that is acceptable to the design of an ALWR power plant. When completed, this document is intended to be a comprehensive statement of utility requirements for the design, construction, and performance of an ALWR power plant for the 1990s and beyond. The Requirements Document consists of three volumes. Volume 1, {open_quotes}ALWR Policy and Summary of Top-Tier Requirements{close_quotes}, is a management-level synopsis of the Requirements Document, including the design objectives and philosophy, the overall physical configuration and features of a future nuclear plant design, and the steps necessary to take the proposed ALWR design criteria beyond the conceptual design state to a completed, functioning power plant. Volume II consists of 13 chapters and contains utility design requirements for an evolutionary nuclear power plant [approximately 1350 megawatts-electric (MWe)]. Volume III contains utility design requirements for nuclear plants for which passive features will be used in their designs (approximately 600 MWe). In April 1992, the staff of the Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory Commission, issued Volume 1 and Volume 2 (Parts 1 and 2) of its safety evaluation report (SER) to document the results of its review of Volumes 1 and 2 of the Requirements Document. Volume 1, {open_quotes}NRC Review of Electric Power Research Institute`s Advanced Light Water Reactor Utility Requirements Document - Program Summary{close_quotes}, provided a discussion of the overall purpose and scope of the Requirements Document, the background of the staff`s review, the review approach used by the staff, and a summary of the policy and technical issues raised by the staff during its review.

  18. NRC review of Electric Power Research Institute`s advanced light water reactor utility requirements document. Passive plant designs, chapters 2-13, project number 669

    SciTech Connect

    Not Available

    1994-08-01

    The Electric Power Research Institute (EPRI) is preparing a compendium of technical requirements, referred to as the {open_quotes}Advanced Light Water Reactor [ALWR] Utility Requirements Document{close_quotes}, that is acceptable to the design of an ALWR power plant. When completed, this document is intended to be a comprehensive statement of utility requirements for the design, construction, and performance of an ALWR power plant for the 1990s and beyond. The Requirements Document consists of three volumes. Volume I, {open_quotes}ALWR Policy and Summary of Top-Tier Requirements{close_quotes}, is a management-level synopsis of the Requirements Document, including the design objectives and philosophy, the overall physical configuration and features of a future nuclear plant design, and the steps necessary to take the proposed ALWR design criteria beyond the conceptual design state to a completed, functioning power plant. Volume II consists of 13 chapters and contains utility design requirements for an evolutionary nuclear power plant [approximately 1350 megawatts-electric (MWe)]. Volume III contains utility design requirements for nuclear plants for which passive features will be used in their designs (approximately 600 MWe). In April 1992, the staff of the Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory Commission, issued Volume 1 and Volume 2 (Parts 1 and 2) of its safety evaluation report (SER) to document the results of its review of Volumes 1 and 2 of the Requirements Document. Volume 1, {open_quotes}NRC Review of Electric Power Research Institute`s Advanced Light Water Reactor Utility Requirements Document - Program Summary{close_quotes}, provided a discussion of the overall purpose and scope of the Requirements Document, the background of the staff`s review, the review approach used by the staff, and a summary of the policy and technical issues raised by the staff during its review.

  19. 100-kWe lunar/Mars surface power utilizing the SP-100 reactor with dynamic conversion

    NASA Astrophysics Data System (ADS)

    Harty, Richard B.; Mason, Lee S.

    Results are presented from a study of the coupling of an SP-100 nuclear reactor with either a Stirling or Brayton power system, at the 100 kWe level, for a power generating system suitable for operation in the lunar and Martian surface environments. In the lunar environment, the reactor and primary coolant loop would be contained in a guard vessel to protect from a loss of primary loop containment. For Mars, all refractory components, including the reactor, coolant, and power conversion components will be contained in a vacuum vessel for protection against the CO2 environment.

  20. Spectroscopic identification of higher-order rare gas-dihalogen complexes with different geometries: He(2,3)...Br(2) and He(2,3)...ICl.

    PubMed

    Boucher, David S; Darr, Joshua P; Strasfeld, David B; Loomis, Richard A

    2008-12-25

    Rovibronic transitions of multiple conformers of the He(2)...(79)Br(2)(X, v'' = 0), He(3)...(79)Br(2)(X, v'' = 0), He(2)...I(35)Cl(X, v'' = 0), and He(3)...I(35)Cl(X, v'' = 0) complexes stabilized in a pulsed, supersonic expansion are observed in action spectra recorded in the B-X region of the dihalogens. In addition to features associated with He(2)...(79)Br(2) and He(2)...I(35)Cl complexes with the rare gas atoms localized in the toroidal potential well lying in a plane perpendicular to the dihalogen bond, those associated with a ground-state conformer that has one He atom localized in the toroidal potential and the other He atom localized in the linear well at the end of the dihalogen moiety are also identified. Transitions of at least three conformers of the He(3)...Br(2) complex and two conformers of the He(3)...ICl complex are also observed. The relative populations of the different conformers are found to depend on where along the supersonic expansion the spectra are recorded, and thus on the local temperature regime sampled. The He(2)...(79)Br(2) and He(2)...I(35)Cl conformers with one He atom in each well are found to be the more stable conformers. PMID:19053811

  1. A possible role for acetylated intermediates in diaminopimelate and tabtoxinine-beta-lactam biosynthesis in Pseudomonas syringae pv. tabaci BR2.024.

    PubMed Central

    Liu, L; Shaw, P D

    1997-01-01

    The deduced product of an open reading frame (ORF3) located in the tabtoxinine-beta-lactam (T beta L) biosynthetic region of Pseudomonas syringae pv. tabaci BR2.024 (BR2.024) has significant sequence homology to the dapD products of other bacteria. dapD encodes L-2,3,4,5-tetrahydrodipicolinate succinyl coenzyme A succinyltransferase (THDPA-ST), an enzyme in the diaminopimelate (DAP) and lysine biosynthetic pathway. Complementation studies, in vitro transcription-translation experiments, and enzymatic assays indicated that ORF3 encodes a product with THDPA-ST activity in Escherichia coli dapD mutant beta 274. However, a BR2.024 mutant with an insert in ORF3 was prototrophic, and only basal THDPA-ST activity was detected in extracts of both parent and mutant. This finding suggested that ORF3 was not required for DAP biosynthesis and that it did not encode a product with THDPA-ST activity. The results of enzymatic studies, indicating that BR2.024 uses acetylated intermediates for DAP biosynthesis, are consistent with the hypothesis that BR2.024 does not need THDPA-ST for DAP biosynthesis. The ORF3 mutant produced reduced levels of tabtoxin, indicating that ORF3 may have a role in T beta L biosynthesis. We have named the gene tabB and have proposed a possible function for the gene product. PMID:9294453

  2. Thermal-hydraulic aspects of flow inversion in a research reactor

    SciTech Connect

    Smith, R.S.; Woodruff, W.L.

    1986-11-01

    PARET, a neutronics and thermal-hydraulics computer code, has been modified to account for natural convection in a reactor core. The code was then used to analyze the flow inversion that occurs in a reactor with heat removal by forced convection in the downward direction after a pump failure. Typical results are shown for a number of parameters. Research reactors normally operating much above ten MW are predicted to experience nucleate boiling in the event of a flow inversion. Comparison with experimental results from the Belgian BR2 reactor indicated general agreement although nucleate boiling that was analytically predicted was not noted in the BR2 data.

  3. SUMMARY AND RESULTS LETTER REPORT – INDEPENDENT VERIFICATION OF THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PROJECT, PHASE 3: TRENCHES 2, 3, AND 4 BROOKHAVEN NATIONAL LABORATORY UPTON, NEW YORK

    SciTech Connect

    E.M. Harpenau

    2010-11-15

    5098-LR-02-0 SUMMARY AND RESULTS LETTER REPORT – INDEPENDENT VERIFICATION OF THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PROJECT, PHASE 3 TRENCHES 2, 3, AND 4 BROOKHAVEN NATIONAL LABORATORY

  4. Long-term storage facility for reactor compartments in Sayda Bay - German support for utilization of nuclear submarines in Russia

    SciTech Connect

    Wolff, Dietmar; Voelzke, Holger; Weber, Wolfgang; Noack, Volker; Baeuerle, Guenther

    2007-07-01

    The German-Russian project that is part of the G8 initiative on Global Partnership Against the Spread of Weapons and Materials of Mass Destruction focuses on the speedy construction of a land-based interim storage facility for nuclear submarine reactor compartments at Sayda Bay near Murmansk. This project includes the required infrastructure facilities for long-term storage of about 150 reactor compartments for a period of about 70 years. The interim storage facility is a precondition for effective activities of decommissioning and dismantlement of almost all nuclear-powered submarines of the Russian Northern Fleet. The project also includes the establishment of a computer-assisted waste monitoring system. In addition, the project involves clearing Sayda Bay of other shipwrecks of the Russian navy. On the German side the project is carried out by the Energiewerke Nord GmbH (EWN) on behalf of the Federal Ministry of Economics and Labour (BMWi). On the Russian side the Kurchatov Institute holds the project management of the long-term interim storage facility in Sayda Bay, whilst the Nerpa Shipyard, which is about 25 km away from the storage facility, is dismantling the submarines and preparing the reactor compartments for long-term interim storage. The technical monitoring of the German part of this project, being implemented by BMWi, is the responsibility of the Federal Institute for Materials Research and Testing (BAM). This paper gives an overview of the German-Russian project and a brief description of solutions for nuclear submarine disposal in other countries. At Nerpa shipyard, being refurbished with logistic and technical support from Germany, the reactor compartments are sealed by welding, provided with biological shielding, subjected to surface treatment and conservation measures. Using floating docks, a tugboat tows the reactor compartments from Nerpa shipyard to the interim storage facility at Sayda Bay where they will be left on the on-shore concrete

  5. 100-kWe Lunar/Mars surface power utilizing the SP-100 reactor with dynamic conversion

    SciTech Connect

    Harty, R.B. ); Mason, L.S. )

    1993-01-15

    An integration study was performed coupling an SP-100 reactor with either a Brayton or Stirling power conversion subsystem. A power level of 100 kWe was selected for the study. The power system was to be compatible with both the lunar and Mars surface environment and require no site preparation. In addition, the reactor was to have integral shielding and be completely self-contained, including its own auxiliary power for start-up. Initial reliability studies were performed to determine power conversion redundancy and engine module size. Previous studies were used to select the power conversion optimum operating conditions (ratio of hot-side temperature to cold-side temperature). Results of the study indicated that either the Brayton or Stirling power conversion subsystems could be integrated with the SP-100 reactor for either a lunar or Mars surface power application. For the lunar environment, the reactor and primary coolant loop would be contained in a guard vessel to protect from a loss of primary loop containment. For the Mars environment, all refractory components including the reactor, primary coolant, and power conversion components would be contained in a vacuum vessel for protection against the CO[sub 2] environment. The vacuum would be maintained by an active ion pumping system. These active ion vacuum systems have no moving parts and have a long history of reliable operation.

  6. 100-kWe Lunar/Mars surface power utilizing the SP-100 reactor with dynamic conversion

    NASA Astrophysics Data System (ADS)

    Harty, Richard B.; Mason, Lee S.

    1993-01-01

    An integration study was performed coupling an SP-100 reactor with either a Brayton or Stirling power conversion subsystem. A power level of 100 kWe was selected for the study. The power system was to be compatible with both the lunar and Mars surface environment and require no site preparation. In addition, the reactor was to have integral shielding and be completely self-contained, including its own auxiliary power for start-up. Initial reliability studies were performed to determine power conversion redundancy and engine module size. Previous studies were used to select the power conversion optimum operating conditions (ratio of hot-side temperature to cold-side temperature). Results of the study indicated that either the Brayton or Stirling power conversion subsystems could be integrated with the SP-100 reactor for either a lunar or Mars surface power application. For the lunar environment, the reactor and primary coolant loop would be contained in a guard vessel to protect from a loss of primary loop containment. For the Mars environment, all refractory components including the reactor, primary coolant, and power conversion components would be contained in a vacuum vessel for protection against the CO2 environment. The vacuum would be maintained by an active ion pumping system. These active ion vacuum systems have no moving parts and have a long history of reliable operation.

  7. Nonadiabatic quantum dynamics of Br 2 in solid Ar: A four-dimensional study of the B to C state predissociation

    NASA Astrophysics Data System (ADS)

    Borowski, A.; Kühn, O.

    2008-05-01

    Quantum dynamics simulations are performed for a diatomics-in-molecules based model of Br 2 in solid Ar which incorporates four nuclear degrees of freedom and four electronic states. The nuclear motions comprise two large amplitude coordinates describing the Br 2 bond distance and an effective symmetry-preserving matrix mode. Two symmetry-lowering harmonic modes are added in the spirit of linear vibronic coupling theory. Initiating the dynamics on the B state by means of an ultrafast laser pulse, nonadiabatic transitions to the two degenerate C states are monitored and the effect of vibrational preexcitation in the electronic ground state is investigated.

  8. UO2 and PuO2 utilization in high temperature engineering test reactor with helium coolant

    NASA Astrophysics Data System (ADS)

    Waris, Abdul; Aji, Indarta K.; Novitrian, Pramuditya, Syeilendra; Su'ud, Zaki

    2016-03-01

    High temperature engineering test reactor (HTTR) is one of high temperature gas cooled reactor (HTGR) types which has been developed by Japanese Atomic Energy Research Institute (JAERI). The HTTR is a graphite moderator, helium gas coolant, 30 MW thermal output and 950 °C outlet coolant temperature for high temperature test operation. Original HTTR uses UO2 fuel. In this study, we have evaluated the use of UO2 and PuO2 in form of mixed oxide (MOX) fuel in HTTR. The reactor cell calculation was performed by using SRAC 2002 code, with nuclear data library was derived from JENDL3.2. The result shows that HTTR can obtain its criticality condition if the enrichment of 235U in loaded fuel is 18.0% or above.

  9. CONVECTION REACTOR

    DOEpatents

    Hammond, R.P.; King, L.D.P.

    1960-03-22

    An homogeneous nuclear power reactor utilizing convection circulation of the liquid fuel is proposed. The reactor has an internal heat exchanger looated in the same pressure vessel as the critical assembly, thereby eliminating necessity for handling the hot liquid fuel outside the reactor pressure vessel during normal operation. The liquid fuel used in this reactor eliminates the necessity for extensive radiolytic gas rocombination apparatus, and the reactor is resiliently pressurized and, without any movable mechanical apparatus, automatically regulates itself to the condition of criticality during moderate variations in temperature snd pressure and shuts itself down as the pressure exceeds a predetermined safe operating value.

  10. Synthesis of Bi4O5Br2 from reorganization of BiOBr and its excellent visible light photocatalytic activity.

    PubMed

    Li, Rui; Xie, Fangxia; Liu, Jianxin; Wang, Yawen; Wang, Yunfang; Zhang, Xiaochao; Fan, Caimei

    2016-06-14

    In this study, a novel visible-light-driven Bi4O5Br2 photocatalyst was successfully synthesized via the structure reorganization of BiOBr at room temperature using NH3·H2O as a structure-controlling agent. The obtained Bi4O5Br2 exhibited outstanding visible light activity and stability compared to BiOBr and P25 for the degradation of resorcinol. The physicochemical properties of Bi4O5Br2 were analyzed and calculated by modern characterization techniques and density functional theory (DFT). The results revealed that the excellent performance could be mainly attributed to the effect of O-richness on the electronic properties of Bi and Br atoms, unique morphology, high visible-light absorption capacity, and prominent oxidation ability of photo-induced holes. Radical trapping experiments demonstrated that h(+) and ˙OH radicals were the dominant active species. Moreover, a structure reorganization mechanism was proposed, revealing that ammonia and the water-steeping process both played important roles in the fabrication of Bi4O5Br2. We believe that this facile method could be extended to fabricate other three component Bi-O-Br nanostructure systems and help elucidate the relationship between BiOBr and BixOyBrz. PMID:27172325

  11. Ablation of TRIP-Br2, a regulator of fat lipolysis, thermogenesis and oxidative metabolism, prevents diet-induced obesity and insulin resistance.

    PubMed

    Liew, Chong Wee; Boucher, Jeremie; Cheong, Jit Kong; Vernochet, Cecile; Koh, Ho-Jin; Mallol, Cristina; Townsend, Kristy; Langin, Dominique; Kawamori, Dan; Hu, Jiang; Tseng, Yu-Hua; Hellerstein, Marc K; Farmer, Stephen R; Goodyear, Laurie; Doria, Alessandro; Blüher, Matthias; Hsu, Stephen I-Hong; Kulkarni, Rohit N

    2013-02-01

    Obesity develops as a result of altered energy homeostasis favoring fat storage. Here we describe a new transcription co-regulator for adiposity and energy metabolism, SERTA domain containing 2 (TRIP-Br2, also called SERTAD2). TRIP-Br2-null mice are resistant to obesity and obesity-related insulin resistance. Adipocytes of these knockout mice showed greater stimulated lipolysis secondary to enhanced expression of hormone sensitive lipase (HSL) and β3-adrenergic (Adrb3) receptors. The knockout mice also have higher energy expenditure because of increased adipocyte thermogenesis and oxidative metabolism caused by upregulating key enzymes in their respective processes. Our data show that a cell-cycle transcriptional co-regulator, TRIP-Br2, modulates fat storage through simultaneous regulation of lipolysis, thermogenesis and oxidative metabolism. These data, together with the observation that TRIP-Br2 expression is selectively elevated in visceral fat in obese humans, suggests that this transcriptional co-regulator is a new therapeutic target for counteracting the development of obesity, insulin resistance and hyperlipidemia. PMID:23291629

  12. Expeditious synthesis of phenanthrenes via CuBr2-catalyzed coupling of terminal alkynes and N-tosylhydrazones derived from o-formyl biphenyls.

    PubMed

    Ye, Fei; Shi, Yi; Zhou, Lei; Xiao, Qing; Zhang, Yan; Wang, Jianbo

    2011-10-01

    A new method for the synthesis of phenanthrenes via ligand-free CuBr(2)-catalyzed coupling/cyclization of terminal alkynes with N-tosylhydrazones derived from o-formyl biphenyls has been developed. This new synthesis has wide range of functional group compatibility. PMID:21875127

  13. Utilization of moving bed biofilm reactor for industrial wastewater treatment containing ethylene glycol: kinetic and performance study.

    PubMed

    Hassani, Amir Hessam; Borghei, Seyed Mehdi; Samadyar, Hassan; Ghanbari, Bastam

    2014-01-01

    One of the requirements for environmental engineering, which is currently being considered, is the removal of ethylene glycol (EG) as a hazardous environmental pollutant from industrial wastewater. Therefore, in a recent study, a moving bed biofilm reactor (MBBR) was applied at pilot scale to treat industrial effluents containing different concentrations of EG (600, 800, 1200, and 1800 mg L-1 ). The removal efficiency and kinetic analysis of the system were examined at different hydraulic retention times of 6, 8, 10, and 12 h as well as influent chemical oxygen demand (COD) ranged between values of 1000 and 3000mg L-1. In minimum and maximum COD Loadings, the MBBR showed 95.1% and 60.7% removal efficiencies, while 95.9% and 66.2% EG removal efficiencies were achieved in the lowest and highest EG concentrations. The results of the reactor modelling suggested compliance of the well-known modified Stover-Kincannon model with the system. PMID:24600890

  14. Measuring Neutron Spectrum at MIT Research Reactor Utilizing He-3 Bonner Cylinder Approach with an Unfolding Analysis

    NASA Astrophysics Data System (ADS)

    Leder, Alexander; Ricochet Collaboration

    2016-03-01

    The Ricochet experiment seeks to measure Coherent (neutral-current) Elastic Neutrino-Nucleus Scattering (CENNS) using dark matter style detectors placed near a neutrino source, possibly the MIT research reactor (MITR), which offers a high continuous neutrino flux at high energies. Currently, Ricochet is characterizing the backgrounds at MITR. The main background is the neutrons emitted simultaneously from the core. To characterize this background, we wrapped a Bonner cylinder around a 3He thermal neutron detector, whose data was then unfolded to produce a neutron energy spectrum across several orders of magnitude. We discuss the resulting spectrum as well its implications for deploying Ricochet in the future.

  15. Final Report on Utilization of TRU TRISO Fuel as Applied to HTR Systems Part II: Prismatic Reactor Cross Section Generation

    SciTech Connect

    Vincent Descotes

    2011-03-01

    The deep-burn prismatic high temperature reactor is made up of an annular core loaded with transuranic isotopes and surrounded in the center and in the periphery by reflector blocks in graphite. This disposition creates challenges for the neutronics compared to usual light water reactor calculation schemes. The longer mean free path of neutrons in graphite affects the neutron spectrum deep inside the blocks located next to the reflector. The neutron thermalisation in the graphite leads to two characteristic fission peaks at the inner and outer interfaces as a result of the increased thermal flux seen in those assemblies. Spectral changes are seen at least on half of the fuel blocks adjacent to the reflector. This spectral effect of the reflector may prevent us from successfully using the two step scheme -lattice then core calculation- typically used for light water reactors. We have been studying the core without control mechanisms to provide input for the development of a complete calculation scheme. To correct the spectrum at the lattice level, we have tried to generate cross-sections from supercell calculations at the lattice level, thus taking into account part of the graphite surrounding the blocks of interest for generating the homogenised cross-sections for the full-core calculation. This one has been done with 2 to 295 groups to assess if increasing the number of groups leads to more accurate results. A comparison with a classical single block model has been done. Both paths were compared to a reference calculation done with MCNP. It is concluded that the agreement with MCNP is better with supercells, but that the single block model remains quite close if enough groups are kept for the core calculation. 26 groups seems to be a good compromise between time and accu- racy. However, some trials with depletion have shown huge variations of the isotopic composition across a block next to the reflector. It may imply that at least an in- core depletion for the

  16. A theoretical simulation of the resonant Raman spectroscopy of the H2O⋯Cl2 and H2O⋯Br2 halogen-bonded complexes.

    PubMed

    Franklin-Mergarejo, Ricardo; Rubayo-Soneira, Jesús; Halberstadt, Nadine; Janda, Kenneth C; Apkarian, V Ara

    2016-02-01

    The resonant Raman spectra of the H2O⋯Cl2 and H2O⋯Br2 halogen-bonded complexes have been studied in the framework of a 2-dimensional model previously used in the simulation of their UV-visible absorption spectra using time-dependent techniques. In addition to the vibrational progression along the dihalogen mode, a progression is observed along the intermolecular mode and its combination with the intramolecular one. The relative intensity of the inter to intramolecular vibrational progressions is about 15% for H2O⋯Cl2 and 33% for H2O⋯Br2. These results make resonant Raman spectra a potential tool for detecting the presence of halogen bonded complexes in condensed phase media such as clathrates and ice. PMID:26851921

  17. Utilization of cross-linked laccase aggregates in a perfusion basket reactor for the continuous elimination of endocrine-disrupting chemicals.

    PubMed

    Cabana, Hubert; Jones, J Peter; Agathos, Spiros N

    2009-04-15

    A perfusion basket reactor (BR) was developed for the continuous utilization of insolubilized laccase as cross-linked enzyme aggregates (CLEAs). The BR consisted of an unbaffled basket made of a metallic filtration module filled with CLEAs and continuously agitated by a 3-blade marine propeller. The agitation conditions influenced both the apparent laccase activity in the reactor and the stability of the biocatalyst. Optimal laccase activity was obtained at a rotational speed of 12.5 rps and the highest stability was reached at speeds of 1.7 rps or lower. The activity and stability of the biocatalyst were affected drastically upon the appearance of vortices in the reaction medium. This reactor was used for the continuous elimination of the endocrine disrupting chemicals (EDCs) nonylphenol (NP), bisphenol A (BPA), and triclosan (TCS). Optimization of EDC elimination by laccase CLEAs as a function of temperature and pH was achieved by response surface methodology using a central composite factorial design. The optimal conditions of pH and temperature were, respectively, 4.8 and 40.3 degrees C for the elimination of p353NP (a branched isomer of NP), 4.7 and 48.0 degrees C for BPA, and 4.9 and 41.2 degrees C for TCS. Finally, the BR was used for the continuous elimination of these EDCs from a 5 mg L(-1) aqueous solution using 1 mg of CLEAs at pH 5 and room temperature. Our results showed that at least 85% of these EDCs could be eliminated with a hydraulic retention time of 325 min. The performances of the BR were quite stable over a 7-day period of continuous treatment. Furthermore, this system could eliminate the same EDCs from a 100 mg L(-1) solution. Finally, a mathematical model combining the Michaelis-Menten kinetics of the laccase CLEAs and the continuous stirred tank reactor behavior of the BR was developed to predict the elimination of these xenobiotics. PMID:19061241

  18. Kinetics of the Reactions of O((sup 3)P) and Cl((sup 2)P) with HBr and Br2

    NASA Technical Reports Server (NTRS)

    Nicovich, J. M.; Wine, P. H.

    1997-01-01

    A laser flash photolysis-resonance fluorescence technique has been employed to study the kinetics of reactions (1)-(4) as a function of temperature. (1) O((sup 3)P) + Br2 yields BrO + Br((sup 2)P(sub 3/2)) at 255-350 K; (2) Cl((sup 2)P) + Br2 yields BrCl + Br((sup 2)P(sub 3/2)) at 298-401 K; (3) O((sup 3)P) + HBr yields OH + Br((sup 2)P(sub J)) at 250-402 K; (4) Cl((sup 2)P) + HBr yields HCl + Br((sup 2)P(sub J)) at 257-404 K. In all cases, the concentration of the excess reagent, i.e, HBr or Br2, was measured in situ in the slow flow system by UV-visible photometry. Heterogeneous dark reactions between XBr (X equals H or Br) and the photolytic precursors for Cl((sup 2)P) and O((sup 3)P) (Cl2 and O3, respectively) were avoided by injecting minimal amounts of precursor into the reaction mixture immediately upstream from the reaction zone. The following Arrhenius expressions summarize our results (errors are 2 sigma and represent precision only, units are cu cm/(molecule.s): k(sub 1) = (1.76 +/- 0.80) x 10(exp -11 exp[(40 +/- 100)/T]; k(sub 2) = (2.40 +/- 1.25) x 12(exp -10) exp[-(144 +/- 176)/T]; k(sub 3) = (5.11 +/- 2.82) x 10(exp -12) exp[-(1450 +/- 160)/T]; k(sub 4) = (2.25 +/- 0.56) x 10(exp -11) exp[-(400 +/- 80)/T]. The consistency (or lack thereof) of our results with those reported in previous kinetics and dynamics studies of reactions (1)-(4) is discussed.

  19. Pd(II)/CuBr2 catalysed keto α-C(sp3)-H benzoxylation of N,N-dialkylamides directed by o-hydroxy groups.

    PubMed

    Santra, Sourav Kumar; Banerjee, Arghya; Rajamanickam, Suresh; Khatun, Nilufa; Patel, Bhisma K

    2016-03-25

    A hydroxy group directed keto α-C(sp3)-H benzoxylation of amides, including N,N-dialkylamides and cyclic amides, has been accomplished involving ortho-hydroxy substrates possessing either an aldehydic or a keto methyl (-COCH3) group with a Pd(II)/CuBr2 catalytic combination. The carboxy group obtained via the in situ oxidation of -CHO or -COCH3 groups of ortho-hydroxy substrates then undergoes a cross-dehydrogenative coupling (CDC) with amides to furnish an α-benzoxylation product with concurrent aromatic ring bromination. PMID:26931492

  20. Generation, utilization, and transformation of cathode electrons for bioreduction of Fe(III)EDTA in a biofilm electrode reactor related to NOx removal from flue gas.

    PubMed

    Li, Wei; Xia, Yinfeng; Zhao, Jingkai; Liu, Nan; Li, Sujing; Zhang, Shihan

    2015-04-01

    A chemical absorption-biological reduction (CABR) integrated system, which employs iron chelate as a solvent, is under development for NOx removal from flue gas. Biofilm electrode reactor (BER) is deemed as a promising bioreactor to regenerate the iron chelate. Although it has been proved that BER can significantly enhance the bioreduction of Fe(III)EDTA, the bioelectrochemistry mechanism involved in the bioreduction of Fe(III)EDTA remains unknown. This work aims to explore this mechanism via the analysis of the generation, utilization, and transformation of cathode electrons in the BER. The results indicate that the generation of cathode electrons follows Faraday's law. The generated cathode electrons were used to produce H2 and directly reduce Fe(III)EDTA in the BER. Meanwhile, the produced H2 served as an electron donor for bioreduction of Fe(III)EDTA. The excess H2 product was transformed to simple organics, e.g., methanol by the hydrogen autotrophy of Pseudomonas under the inorganic and anaerobic conditions. Overall, this work revealed that the reduction of Fe(III)EDTA in the BER was enhanced by both direct electrochemical reduction and indirect bioreduction using H2 as an intermediate. It is also interesting that the excess H2 product was transformed to methanol for microbial metabolism and energy storage in the BER. PMID:25799265

  1. M4Se 16Br 2 ( M = Nb, Ta), a new chain-like structure from progressive condensation of ( M2Se 4) groups

    NASA Astrophysics Data System (ADS)

    Grenouilleau, P.; Meerschaut, A.; Guemas, L.; Rouxel, J.

    1987-02-01

    Nb 4Se 16Br 2 and Ta 4Se 16Br 2 crystallize in the monoclinic system, space group {P2 1}/{c} with a = 12.862(3)Å, b = 13.862(3) Å, c = 16.029(3) Å, β = 127.70(1)°, Z = 4 and a = 12.844(2) Å, b = 13.875(2) Å, c = 16.018(4) Å, β = 127.57(1)°, Z = 4, respectively. The structures were solved from 3182 and 2784 reflections, respectively, collected on a NONIUS CAD4 automatic diffractometer (Mo Kα radiation). The final R indexes are 0.030 and 0.033. The common structural type is based on the presence of four chains running in a direction parallel to the a axis. Along the chains four metal atoms are found; short and long M- M distances alternate in the sequence of three consecutive short bonds ( overlined(M-M) ˜- 3.1 Å) and one long ( overlined(M … M) ˜- 3.7 Å). The shortest bonds are associated with [ M4Se 12] groups built up from the condensation of three [ M2Se 4] units.

  2. A chopper system for shortening the duration of pulsed supersonic beams seeded with NO or Br2 down to 13 μs

    NASA Astrophysics Data System (ADS)

    Lam, Jessica; Rennick, Christopher J.; Softley, Timothy P.

    2015-05-01

    A chopper wheel construct is used to shorten the duration of a molecular beam to 13 μs. Molecular beams seeded with NO or with Br2 and an initial pulse width of ≥200 μs were passed through a spinning chopper wheel, which was driven by a brushless DC in vacuo motor at a range of speeds, from 3000 rpm to 80 000 rpm. The resulting duration of the molecular-beam pulses measured at the laser detection volume ranged from 80 μs to 13 μs and was the same for both NO and Br2. The duration is consistent with a simple analytical model, and the minimum pulse width measured is limited by the spreading of the beam between the chopper and the detection point as a consequence of the longitudinal velocity distribution of the beam. The setup adopted here effectively eliminates buildup of background gas without the use of a differential pumping stage, and a clean narrow pulse is obtained with low rotational temperature.

  3. Effect of excess PbBr2 on photoluminescence spectra of CH3NH3PbBr3 perovskite particles at room temperature

    NASA Astrophysics Data System (ADS)

    Fang, Xin; Zhang, Kun; Li, Yanping; Yao, Li; Zhang, Yinfeng; Wang, Yilun; Zhai, Wenhao; Tao, Li; Du, Honglin; Ran, Guangzhao

    2016-02-01

    The organic-inorganic halide perovskites have promising applications in light-emitting devices besides solar cells. We here prepare CH3NH3PbBr3 perovskite particles on SiO2 substrates and find that the photoluminescence (PL) spectrum of the particles at room temperature has two peaks, locating at 529 and 549 nm, respectively, much different from that of the corresponding films prepared on the oxygen plasma-cleaned SiO2 substrates, which has a single peak. The double peaks have different temperature-dependence behaviors. By the x-ray diffraction and energy dispersive x-ray spectroscopy analyses, excess PbBr2 is detected inside the particles. We deduce that such excess PbBr2 has introduced shallow level defects. It is concluded that band-to-band recombination and these defects result in the double-peaked feature of the PL spectra of CH3NH3PbBr3 particles at room temperature.

  4. Characterization of dapB, a gene required by Pseudomonas syringae pv. tabaci BR2.024 for lysine and tabtoxinine-beta-lactam biosynthesis.

    PubMed Central

    Liu, L; Shaw, P D

    1997-01-01

    The dapB gene, which encodes L-2,3-dihydrodipicolinate reductase, the second enzyme of the lysine branch of the aspartic amino acid family, was cloned and sequenced from a tabtoxin-producing bacterium, Pseudomonas syringae pv. tabaci BR2.024. The deduced amino acid sequence shared 60 to 90% identity to known dapB gene products from gram-negative bacteria and 19 to 21% identity to the dapB products from gram-positive bacteria. The consensus sequence for the NAD(P)H binding site [(V/I)(A/G)(V/I)XGXXGXXG)] and the proposed substrate binding site (HHRHK) were conserved in the polypeptide. A BR2.024 dapB mutant is a diaminopimelate auxotroph and tabtoxin negative. The addition of a mixture of L-,L-, D,D-, and meso-diaminopimelate to defined media restored growth but not tabtoxin production. Cloned DNA fragments containing the parental dapB gene restored the ability to grow in defined media and tabtoxin production to the dapB mutant. These results indicate that the dapB gene is required for both lysine and tabtoxin biosynthesis, thus providing the first genetic evidence that the biosynthesis of tabtoxin proceeds in part along the lysine biosynthetic pathway. These data also suggest that L-2,3,4,5-tetrahydrodipicolinate is a common intermediate for both lysine and tabtoxin biosynthesis. PMID:8990304

  5. Modeling and simulation of output power of a high-power He-SrBr2 laser by using multivariate adaptive regression splines

    NASA Astrophysics Data System (ADS)

    Iliev, I. P.; Gocheva-Ilieva, S. G.

    2013-02-01

    Due to advancement in computing technology researchers are focusing onto novel predictive models and techniques for improving the design and performance of the devices. This study examines a recently developed high-powered SrBr2 laser excited in a nanosecond pulse longitudinal He-SrBr2 discharge. Based on the accumulated experiment data, a new approach is proposed for determining the relationship between laser output power and basic laser characteristics: geometric design, supplied electric power, helium pressure, etc. Piece-wise linear and nonlinear statistical models have been built with the help of the flexible predictive MARS technique. It is shown that the best nonlinear MARS model containing second degree terms provides the best description of the examined data, demonstrating a coefficient of determination of over 99%. The resulting theoretical models are used to estimate and predict the experiment as well as to analyze the local behavior of the relationships between laser output power and input laser characteristics. The second order model is applied to the design and optimization of the laser in order to enhance laser generation.

  6. [UO2(NH3)5]Br2·NH3: synthesis, crystal structure, and speciation in liquid ammonia solution by first-principles molecular dynamics simulations.

    PubMed

    Woidy, Patrick; Bühl, Michael; Kraus, Florian

    2015-04-28

    Pentaammine dioxido uranium(VI) dibromide ammonia (1/1), [UO2(NH3)5]Br2·NH3, was synthesized in the form of yellow crystals by the reaction of uranyl bromide, UO2Br2, with dry liquid ammonia. The compound crystallizes orthorhombic in space group Cmcm and is isotypic to [UO2(NH3)5]Cl2·NH3 with a = 13.2499(2), b = 10.5536(1), c = 8.9126(1) Å, V = 1246.29(3) Å(3) and Z = 4 at 123 K. The UO2(2+) cation is coordinated by five ammine ligands and the coordination polyhedron can be best described as pentagonal bipyramid. Car-Parrinello molecular dynamics simulations are reported for [UO2(NH3)5](2+) in the gas phase and in liquid NH3 solution (using the BLYP density functional). According to free-energy simulations, solvation by ammonia has only a small effect on the uranyl-NH3 bond strength. PMID:25797497

  7. Multicapillary Flow Reactor: Synthesis of 1,2,5-Thiadiazepane 1,1-Dioxide Library Utilizing One-Pot Elimination and Inter-/Intramolecular Double aza-Michael Addition Via Microwave-Assisted, Continuous-Flow Organic Synthesis (MACOS)

    PubMed Central

    Ullah, Farman; Zang, Qin; Javed, Salim; Zhou, Aihua; Knudtson, Christopher A.; Bi, Danse; Hanson, Paul R.; Organ, Michael G.

    2013-01-01

    A microwave-assisted, continuous-flow organic synthesis (MACOS) protocol for the synthesis of functionalized 1,2,5-thiadiazepane 1,1-dioxide library, utilizing a one-pot elimination and inter-/intramolecular double aza-Michael addition strategy is reported. The optimized protocol in MACOS was utilized for scale-out and further extended for library production using a multicapillary flow reactor. A 50-member library of 1,2,5-thiadiazepane 1,1-dioxides was prepared on a 100- to 300-mg scale with overall yields between 50 and 80% and over 90 % purity determined by proton nuclear magnetic resonance (1H-NMR) spectroscopy. PMID:24244871

  8. Low-dimensional charge transport of the ferroic NH 2(C 2H 5) 4CoCl 2Br 2 nanocrystals

    NASA Astrophysics Data System (ADS)

    Tkaczyk, S. W.; Kityk, I. V.; Rudyk, V.; Kapustianyk, V.

    2010-06-01

    DC-conductivity of the nanocomposites consisting of ferroic nanocrystals NH 2(C 2H 5) 4CoCl 2Br 2 (TEA-CCB) incorporated into the polymer PMMA matrices is investigated. The investigations are performed for different number of nanocrystallite chromophores and thickness of the samples. The thickness of the nanocomposite films was varied within 0.44-0.48 μm. The measurements were done at different temperatures and different applied voltages. As a dominant mechanism thermoemission was considered, which is determined by temperature of the samples.. The gold electrodes were used as principle electrodes. The observed phenomena were explained within a framework of hopping between the trapping levels and possible contribution of self-trapped excitons.

  9. Temperature dependence of Peierls–Hubbard phase transition in [Pd(cptn)2Br]Br2 studied by scanning tunneling microscopy

    NASA Astrophysics Data System (ADS)

    Hosomi, Yuka; Yoshida, Shoji; Taninaka, Atsushi; Yoshida, Takefumi; Takaishi, Shinya; Takeuchi, Osamu; Yamashita, Masahiro; Shigekawa, Hidemi

    2016-08-01

    The temperature dependence of the Peierls–Hubbard phase transition in [Pd(cptn)2Br]Br2 (cptn: 1R,2R-diaminocyclopentane) was directly observed using a low-temperature scanning tunneling microscope. A short ligand without alkyl chains was used to form a rigid crystal lattice to reduce the effect of structural changes in the crystal with temperature. The hysteresis in the temperature dependence of the ratio between the areas of the charge density wave (CDW) state produced by the PdII–PdIV mixed-valence state and the Mott–Hubbard (MH) state with a PdIII-averaged valence state which is a characteristic of the first-order phase transition, was directly observed at the atomic scale. Pinning of the CDW phase by defects was observed below the critical temperature, suggesting the growth of the CDW phase with defects as nuclei.

  10. Anomalous low-temperature behavior of the Co dimers in the oxo-halide CoSb 2O 3Br 2

    NASA Astrophysics Data System (ADS)

    Hugonin, Zuzana; Johnsson, Mats; Lidin, Sven; Wulferding, Dirk; Lemmens, Peter; Kremer, Reinhard K.

    2008-10-01

    We report the synthesis, crystal structure determination, magnetic and low-temperature structural properties of a new cobalt antimony oxo-bromide. CoSb 2O 3Br 2 crystallizes in the triclinic crystal system, space group P-1, with the following lattice parameters: a=5.306(3) Å, b=7.812(4) Å, c=8.0626(10) Å, α=88.54(3)°, β=82.17(3)°, γ=80.32(4)°, and Z=2. The crystal structure was solved from single crystal X-ray data and refined on F2, R1=3.08. The structure consists of layers made up by three building blocks, [CoO 4Br 2], [SbO 3Br], and [SbO 3] that are connected via edge- and corner-sharing so that structural Co-Co dimers are formed. The layers have no net charge and are only weakly connected by van der Waals forces to adjacent layers. Above ˜25 K the magnetic susceptibility is independent of the magnetic field and can be very well described by a Curie-Weiss law. Below 25 K the susceptibility passes through a maximum and decreases again that is typical for the onset of long-range antiferromagnetic correlations. Long-range antiferromagnetic ordering is observed below TN˜9 K indicating substantial inter-dimer exchange coupling between Co-Co dimers within the layers. However, according to the heat capacity results only a minute fraction of the entropy is associated with the long-range ordering transition. The phonon anomalies observed for T<6 K in Raman scattering and an anomaly in the specific heat point to a structural instability leading to a loss of inversion symmetry at lowest temperatures.

  11. NUCLEAR REACTOR

    DOEpatents

    Grebe, J.J.

    1959-07-14

    High temperature reactors which are uniquely adapted to serve as the heat source for nuclear pcwered rockets are described. The reactor is comprised essentially of an outer tubular heat resistant casing which provides the main coolant passageway to and away from the reactor core within the casing and in which the working fluid is preferably hydrogen or helium gas which is permitted to vaporize from a liquid storage tank. The reactor core has a generally spherical shape formed entirely of an active material comprised of fissile material and a moderator material which serves as a diluent. The active material is fabricated as a gas permeable porous material and is interlaced in a random manner with very small inter-connecting bores or capillary tubes through which the coolant gas may flow. The entire reactor is divided into successive sections along the direction of the temperature gradient or coolant flow, each section utilizing materials of construction which are most advantageous from a nuclear standpoint and which at the same time can withstand the operating temperature of that particular zone. This design results in a nuclear reactor characterized simultaneously by a minimum critiral size and mass and by the ability to heat a working fluid to an extremely high temperature.

  12. Utilization of 134Cs/137Cs in the environment to identify the reactor units that caused atmospheric releases during the Fukushima Daiichi accident

    PubMed Central

    Chino, Masamichi; Terada, Hiroaki; Nagai, Haruyasu; Katata, Genki; Mikami, Satoshi; Torii, Tatsuo; Saito, Kimiaki; Nishizawa, Yukiyasu

    2016-01-01

    The Fukushima Daiichi nuclear power reactor units that generated large amounts of airborne discharges during the period of March 12–21, 2011 were identified individually by analyzing the combination of measured 134Cs/137Cs depositions on ground surfaces and atmospheric transport and deposition simulations. Because the values of 134Cs/137Cs are different in reactor units owing to fuel burnup differences, the 134Cs/137Cs ratio measured in the environment was used to determine which reactor unit ultimately contaminated a specific area. Atmospheric dispersion model simulations were used for predicting specific areas contaminated by each dominant release. Finally, by comparing the results from both sources, the specific reactor units that yielded the most dominant atmospheric release quantities could be determined. The major source reactor units were Unit 1 in the afternoon of March 12, 2011, Unit 2 during the period from the late night of March 14 to the morning of March 15, 2011. These results corresponded to those assumed in our previous source term estimation studies. Furthermore, new findings suggested that the major source reactors from the evening of March 15, 2011 were Units 2 and 3 and that the dominant source reactor on March 20, 2011 temporally changed from Unit 3 to Unit 2. PMID:27546490

  13. Utilization of (134)Cs/(137)Cs in the environment to identify the reactor units that caused atmospheric releases during the Fukushima Daiichi accident.

    PubMed

    Chino, Masamichi; Terada, Hiroaki; Nagai, Haruyasu; Katata, Genki; Mikami, Satoshi; Torii, Tatsuo; Saito, Kimiaki; Nishizawa, Yukiyasu

    2016-01-01

    The Fukushima Daiichi nuclear power reactor units that generated large amounts of airborne discharges during the period of March 12-21, 2011 were identified individually by analyzing the combination of measured (134)Cs/(137)Cs depositions on ground surfaces and atmospheric transport and deposition simulations. Because the values of (134)Cs/(137)Cs are different in reactor units owing to fuel burnup differences, the (134)Cs/(137)Cs ratio measured in the environment was used to determine which reactor unit ultimately contaminated a specific area. Atmospheric dispersion model simulations were used for predicting specific areas contaminated by each dominant release. Finally, by comparing the results from both sources, the specific reactor units that yielded the most dominant atmospheric release quantities could be determined. The major source reactor units were Unit 1 in the afternoon of March 12, 2011, Unit 2 during the period from the late night of March 14 to the morning of March 15, 2011. These results corresponded to those assumed in our previous source term estimation studies. Furthermore, new findings suggested that the major source reactors from the evening of March 15, 2011 were Units 2 and 3 and that the dominant source reactor on March 20, 2011 temporally changed from Unit 3 to Unit 2. PMID:27546490

  14. POWER REACTOR

    DOEpatents

    Zinn, W.H.

    1958-07-01

    A fast nuclear reactor system ls described for producing power and radioactive isotopes. The reactor core is of the heterogeneous, fluid sealed type comprised of vertically arranged elongated tubular fuel elements having vertical coolant passages. The active portion is surrounded by a neutron reflector and a shield. The system includes pumps and heat exchangers for the primary and secondary coolant circuits. The core, primary coolant pump and primary heat exchanger are disposed within an irapenforate tank which is filled with the primary coolant, in this case a liquid metal such as Na or NaK, to completely submerge these elements. The tank is completely surrounded by a thick walled concrete shield. This reactor system utilizes enriched uranium or plutonium as the fissionable material, uranium or thorium as a diluent and thorium or uranium containing less than 0 7% of the U/sup 235/ isotope as a fertile material.

  15. Utilization of high-strength wastewater for the production of biogas as a renewable energy source using hybrid upflow anaerobic sludge blanket (HUASB) reactor

    SciTech Connect

    Shivayogimath, C.B.; Ramanujam, T.K.

    1998-07-01

    Anaerobic digestion of distillery spentwash, a high-strength wastewater, was studied using a hybrid upflow anaerobic sludge blanket (HUASB) reactor for 240 days under ambient conditions. The HUASB reactor combined an open volume in the bottom two-thirds of the reactor for sludge blanket and polypropylene pall rings packing in the upper one-third of the reactor. The aim of the study was to achieve optimum biogas production and waste treatment. Using non-granular anaerobic sewage sludge as seed, the start-up of the HUASB reactor was successfully completed, with the production of active bacterial granules of 1--2 mm size, within 90 days. Examination of the bacterial granules under scanning electron microscope (SEM) revealed that Methanothrix like microorganisms were the dominant species besides Methanosarcina. An organic loading of 24 kg COD/m{sup 3}d at a low hydraulic retention time (HRT) of 6 hours was achieved with 82% reduction in COD. Biogas with high methane content (80%) was produced at these loadings. The specific biogas yield was 0.36 m{sup 3} CH{sub 4}/kg COD. Packing in the upper third of the reactor was very efficient as a gas-solid separator (GSS); and in addition it retained the biomass.

  16. HOMOGENEOUS NUCLEAR POWER REACTOR

    DOEpatents

    King, L.D.P.

    1959-09-01

    A homogeneous nuclear power reactor utilizing forced circulation of the liquid fuel is described. The reactor does not require fuel handling outside of the reactor vessel during any normal operation including complete shutdown to room temperature, the reactor being selfregulating under extreme operating conditions and controlled by the thermal expansion of the liquid fuel. The liquid fuel utilized is a uranium, phosphoric acid, and water solution which requires no gus exhaust system or independent gas recombining system, thereby eliminating the handling of radioiytic gas.

  17. Temperature induced changes on the structure and the dynamics of the ``tetrahedral'' glasses and melts of ZnCl2 and ZnBr2

    NASA Astrophysics Data System (ADS)

    Yannopoulos, S. N.; Kalampounias, A. G.; Chrissanthopoulos, A.; Papatheodorou, G. N.

    2003-02-01

    Glassy, supercooled, and molten ZnCl2 and ZnBr2 have been studied by Raman spectroscopy over the broad temperature range -196 to 800 °C in an effort to follow in detail the structural changes caused by temperature variation. A systematic study has also been undertaken for the corresponding crystalline polymorphs showing that each material exists in only one crystalline phase if water traces are not present. The reduced isotropic and anisotropic Raman spectra of the ZnCl2 and ZnBr2 glasses and melts are isomorphous. Unusually drastic changes of the relative intensities of particular bands occur with temperature in the reduced isotropic spectra. A comparison between the spectral features of crystals, glasses, and melts has revealed that the network structure of the glasses and melts consists of ZnX4/2 (X=Br,Cl) tetrahedra bound to each other by apex- and edge-bridged halides. The substructure of the glass/melt is formed by mixing a variety of tetrahedra participating in "open," "cluster," and "chain" networks which are bound to each other by bridged halides. The boundaries of the substructure involve neutral or charged terminal halide bonds with zinc of an average threefold coordination. Temperature rise breaks up the substructure to smaller fragments, increases the number of terminal bonds, and rearranges the apex- and edge-bridging networks. The good glass-forming ability of the ZnX2 melts is attributed to the existence and mixing of the three topologically different networks within the substructure. Our data of ZnCl2 are in qualitative agreement with molecular dynamics simulations as regards the frequency distribution of vibrational modes. However, simulations are not able to correctly predict polarization properties in the glass and the melt. The low-frequency Raman spectra reveal the presence of the Boson peak in both glasses, which interestingly persists, well resolved, also into the normal liquid state above the melting point. The spectra in the region of the

  18. Behavior of BaBr2, BaI2, and BaCl2 at high pressure as analogs to SiO2.

    NASA Astrophysics Data System (ADS)

    Smart, T. J.; Stackhouse, S.; Diamond, M. R.; Godwal, B. K.; Jeanloz, R.

    2015-12-01

    Motivated by the expectation that giant and supergiant planets likely contain rocky components in their cores, we study analogs of the archetypal rock constituent, SiO2. The crystal structures of SiO2 under ultra-high pressures, greater than feasible experimental conditions, are believed to be documented by the high pressure structural sequence of AX2 compounds. Experimental and theoretical work agree on a high pressure transition to the cotunnite (orthorhombic) phase, with first-principles theory predicting that SiO2 transforms to the cotunnite structure at 750 GPa. However, the existence of a postcotunnite (monoclinic) phase as the final high pressure polymorph, suggested by X-ray diffraction (XRD) experiments on ambient pressure cotunnite-structured AX2 compounds (e.g. PbCl2, SnCl2), has been challenged by density-functional theory (DFT) computations. This disagreement could perhaps be due to sensitivity in diamond-anvil cell (DAC) experiments to pressure gradients; conversely, it could perhaps arise from limitations of DFT. This study further explores both the experimental and theoretical sides of this debate, with an aim to resolve this discrepancy. We present synchrotron XRD data on the AX2 compounds BaCl2, BaBr2, and BaI2, compressed up to 70 GPa at room temperature in a DAC. Here we compare our experimentally observed crystallography and equations of state with results from our DFT simulations.

  19. Mn-Promoted Co3O4/TiO2 as an efficient catalyst for catalytic oxidation of dibromomethane (CH2Br2).

    PubMed

    Mei, Jian; Zhao, Songjian; Huang, Wenjun; Qu, Zan; Yan, Naiqiang

    2016-11-15

    Brominated hydrocarbon is the typical pollutant in the exhaust gas from the synthesis process of Purified Terephthalic Acid (PTA), which may cause various environmental problems once emitted into atmosphere. Dibromomethane (DBM) was employed as the model compound in this study, and a series of TiO2-supported manganese and cobalt oxide catalysts with different Mn/Co molar ratio were prepared by the impregnation method and used for catalytic oxidation of DBM. It was found that the addition of Mn significantly enhanced the catalytic performance of Co/TiO2 catalyst. Among all the prepared catalysts, Mn(1)-Co/TiO2 (Mn/Co molar ratio was 1) catalyst exhibited the highest activity with T90 at about 325°C and good stability maintained for at least 30h at 500ppm DBM and 10% O2 at GHSV=60,000h(-1), and the final products in the reaction were COx, HBr and Br2, without the formation of Br-containing organics. The high activity and high stability might be attributed to the redox cycle (Co(2+)+Mn(4+)↔Co(3+)+Mn(3+)) over Mn-promoted Co3O4/TiO2 catalyst. Based on the results of in situ DRIFT studies and analysis of products, a plausible reaction mechanism for catalytic oxidation of DBM over Mn-Co/TiO2 catalysts was also proposed. PMID:27388418

  20. Novel Co(III)/Co(II) mixed valence compound [Co(bapen)Br2]2[CoBr4] (bapen = N,N‧-bis(3-aminopropyl)ethane-1,2-diamine): Synthesis, crystal structure and magnetic properties

    NASA Astrophysics Data System (ADS)

    Smolko, Lukáš; Černák, Juraj; Kuchár, Juraj; Miklovič, Jozef; Boča, Roman

    2016-09-01

    Green crystals of Co(III)/Co(II) mixed valence compound [Co(bapen)Br2]2[CoBr4] (bapen = N,N‧-bis(3-aminopropyl)ethane-1,2-diamine) were isolated from the aqueous system CoBr2 - bapen - HBr, crystallographically studied and characterized by elemental analysis and IR spectroscopy. Its ionic crystal structure is built up of [Co(bapen)Br2]+ cations and [CoBr4]2- anions. The Co(III) central atoms within the complex cations are hexacoordinated (donor set trans-N4Br2) with bromido ligands placed in the axial positions. The Co(II) atoms exhibit distorted tetrahedral coordination. Beside ionic forces weak Nsbnd H⋯Br intermolecular hydrogen bonding interactions contribute to the stability of the structure. Temperature variable magnetic measurements confirm the S = 3/2 behavior with the zero-field splitting of an intermediate strength: D/hc = 8.7 cm-1.

  1. NEUTRONIC REACTOR FUEL COMPOSITION

    DOEpatents

    Thurber, W.C.

    1961-01-10

    Uranium-aluminum alloys in which boron is homogeneously dispersed by adding it as a nickel boride are described. These compositions have particular utility as fuels for neutronic reactors, boron being present as a burnable poison.

  2. Radiation Shielding Design and Orientation Considerations for a 1 kWe Heat Pipe Cooled Reactor Utilized to Bore Through the Ice Caps of Mars

    SciTech Connect

    Fensin, Michael L.; Elliott, John O.; Lipinski, Ronald J.; Poston, David I.

    2006-01-20

    The goal in designing any space power system is to develop a system able to meet the mission requirements for success while minimizing the overall costs. The mission requirements for the this study was to develop a reactor (with Stirling engine power conversion) and shielding configuration able to fit, along with all the other necessary science equipment, in a Cryobot 3 m high with {approx}0.5 m diameter hull, produce 1 kWe for 5yrs, and not adversely affect the mission science by keeping the total integrated dose to the science equipment below 150 krad. Since in most space power missions the overall system mass dictates the mission cost, the shielding designs in this study incorporated Martian water extracted at the startup site in order to minimize the tungsten and LiH mass loading at launch. Different reliability and mass minimization concerns led to three design configuration evolutions. With the help of implementing Martian water and configuring the reactor as far from the science equipment as possible, the needed tungsten and LiH shield mass was minimized. This study further characterizes the startup dose and the necessary mission requirements in order to ensure integrity of the surface equipment during reactor startup phase.

  3. Regeneration of barium carbonate from barium sulphide in a pilot-scale bubbling column reactor and utilization for acid mine drainage.

    PubMed

    Mulopo, J; Zvimba, J N; Swanepoel, H; Bologo, L T; Maree, J

    2012-01-01

    Batch regeneration of barium carbonate (BaCO(3)) from barium sulphide (BaS) slurries by passing CO(2) gas into a pilot-scale bubbling column reactor under ambient conditions was used to assess the technical feasibility of BaCO(3) recovery in the Alkali Barium Calcium (ABC) desalination process and its use for sulphate removal from high sulphate Acid Mine Drainage (AMD). The effect of key process parameters, such as BaS slurry concentration and CO(2) flow rate on the carbonation, as well as the extent of sulphate removal from AMD using the recovered BaCO(3) were investigated. It was observed that the carbonation reaction rate for BaCO(3) regeneration in a bubbling column reactor significantly increased with increase in carbon dioxide (CO(2)) flow rate whereas the BaS slurry content within the range 5-10% slurry content did not significantly affect the carbonation rate. The CO(2) flow rate also had an impact on the BaCO(3) morphology. The BaCO(3) recovered from the pilot-scale bubbling column reactor demonstrated effective sulphate removal ability during AMD treatment compared with commercial BaCO(3). PMID:22233912

  4. Radiation Shielding Design and Orientation Considerations for a 1 kWe Heat Pipe Cooled Reactor Utilized to Bore Through the Ice Caps of Mars

    NASA Astrophysics Data System (ADS)

    Fensin, Michael L.; Elliott, John O.; Lipinski, Ronald J.; Poston, David I.

    2006-01-01

    The goal in designing any space power system is to develop a system able to meet the mission requirements for success while minimizing the overall costs. The mission requirements for the this study was to develop a reactor (with Stirling engine power conversion) and shielding configuration able to fit, along with all the other necessary science equipment, in a Cryobot 3 m high with ~0.5 m diameter hull, produce 1 kWe for 5yrs, and not adversely affect the mission science by keeping the total integrated dose to the science equipment below 150 krad. Since in most space power missions the overall system mass dictates the mission cost, the shielding designs in this study incorporated Martian water extracted at the startup site in order to minimize the tungsten and LiH mass loading at launch. Different reliability and mass minimization concerns led to three design configuration evolutions. With the help of implementing Martian water and configuring the reactor as far from the science equipment as possible, the needed tungsten and LiH shield mass was minimized. This study further characterizes the startup dose and the necessary mission requirements in order to ensure integrity of the surface equipment during reactor startup phase.

  5. Thermionic reactor program - An overview.

    NASA Technical Reports Server (NTRS)

    Beard, D. S.; Lynch, J. J.

    1972-01-01

    An overview of the AEC/NASA thermionic reactor program is presented with emphasis on the latest progress in this technology. The possible applications for utilization of thermionic reactors are reviewed and the joint AEC/NASA program approach to demonstrate thermionic technology is outlined. The thermionic reactor technology programs of France, West Germany, and the Soviet Union are highlighted.

  6. ELECTRONUCLEAR REACTOR

    DOEpatents

    Lawrence, E.O.; McMillan, E.M.; Alvarez, L.W.

    1960-04-19

    An electronuclear reactor is described in which a very high-energy particle accelerator is employed with appropriate target structure to produce an artificially produced material in commercial quantities by nuclear transformations. The principal novelty resides in the combination of an accelerator with a target for converting the accelerator beam to copious quantities of low-energy neutrons for absorption in a lattice of fertile material and moderator. The fertile material of the lattice is converted by neutron absorption reactions to an artificially produced material, e.g., plutonium, where depleted uranium is utilized as the fertile material.

  7. Computational fluid dynamics analyses of lateral heat conduction, coolant azimuthal mixing and heat transfer predictions in a BR2 fuel assembly geometry.

    SciTech Connect

    Tzanos, C. P.; Dionne, B.

    2011-05-23

    To support the analyses related to the conversion of the BR2 core from highly-enriched (HEU) to low-enriched (LEU) fuel, the thermal-hydraulics codes PLTEMP and RELAP-3D are used to evaluate the safety margins during steady-state operation (PLTEMP), as well as after a loss-of-flow, loss-of-pressure, or a loss of coolant event (RELAP). In the 1-D PLTEMP and RELAP simulations, conduction in the azimuthal and axial directions is not accounted. The very good thermal conductivity of the cladding and the fuel meat and significant temperature gradients in the lateral directions (axial and azimuthal directions) could lead to a heat flux distribution that is significantly different than the power distribution. To evaluate the significance of the lateral heat conduction, 3-D computational fluid dynamics (CFD) simulations, using the CFD code STAR-CD, were performed. Safety margin calculations are typically performed for a hot stripe, i.e., an azimuthal region of the fuel plates/coolant channel containing the power peak. In a RELAP model, for example, a channel between two plates could be divided into a number of RELAP channels (stripes) in the azimuthal direction. In a PLTEMP model, the effect of azimuthal power peaking could be taken into account by using engineering factors. However, if the thermal mixing in the azimuthal direction of a coolant channel is significant, a stripping approach could be overly conservative by not taking into account this mixing. STAR-CD simulations were also performed to study the thermal mixing in the coolant. Section II of this document presents the results of the analyses of the lateral heat conduction and azimuthal thermal mixing in a coolant channel. Finally, PLTEMP and RELAP simulations rely on the use of correlations to determine heat transfer coefficients. Previous analyses showed that the Dittus-Boelter correlation gives significantly more conservative (lower) predictions than the correlations of Sieder-Tate and Petukhov. STAR-CD 3-D

  8. HORIZONTAL BOILING REACTOR SYSTEM

    DOEpatents

    Treshow, M.

    1958-11-18

    Reactors of the boiling water type are described wherein water serves both as the moderator and coolant. The reactor system consists essentially of a horizontal pressure vessel divided into two compartments by a weir, a thermal neutronic reactor core having vertical coolant passages and designed to use water as a moderator-coolant posltioned in one compartment, means for removing live steam from the other compartment and means for conveying feed-water and water from the steam compartment to the reactor compartment. The system further includes auxiliary apparatus to utilize the steam for driving a turbine and returning the condensate to the feed-water inlet of the reactor. The entire system is designed so that the reactor is self-regulating and has self-limiting power and self-limiting pressure features.

  9. A theoretical simulation of the resonant Raman spectroscopy of the H2O⋯Cl2 and H2O⋯Br2 halogen-bonded complexes

    NASA Astrophysics Data System (ADS)

    Franklin-Mergarejo, Ricardo; Rubayo-Soneira, Jesús; Halberstadt, Nadine; Janda, Kenneth C.; Apkarian, V. Ara

    2016-02-01

    The resonant Raman spectra of the H2O⋯Cl2 and H2O⋯Br2 halogen-bonded complexes have been studied in the framework of a 2-dimensional model previously used in the simulation of their UV-visible absorption spectra using time-dependent techniques. In addition to the vibrational progression along the dihalogen mode, a progression is observed along the intermolecular mode and its combination with the intramolecular one. The relative intensity of the inter to intramolecular vibrational progressions is about 15% for H2O⋯Cl2 and 33% for H2O⋯Br2. These results make resonant Raman spectra a potential tool for detecting the presence of halogen bonded complexes in condensed phase media such as clathrates and ice.

  10. Preparation and characterization of poly(glycidyl methacrylate)-grafted magnetic nanoparticles: Effects of the precursor concentration on polyol synthesis of Fe3O4 and [PMDETA]0/[CuBr2]0 ratios on SI-AGET ATRP

    NASA Astrophysics Data System (ADS)

    Jiang, Liping; Zhou, Xuyang; Wei, Guyun; Lu, Xiaoduo; Wei, Weiping; Qiu, Jianhua

    2015-12-01

    Polymer brushes based on poly(glycidyl methacrylate) (PGMA) have been successfully grafted from the surface of silica coated iron oxide (Fe3O4@SiO2) nanoparticles via surface-initiated activators generated by electron transfer atom transfer radical polymerization (SI-AGET ATRP). The size of the nanoparticles could be adjusted from 7.3 to 9.6 nm by varying the precursor concentration of iron(III) acetylacetonate. The Fe3O4 nanoparticles possessed a highly crystalline structure, and the saturation magnetization of the as-prepared magnetite was strongly related to the particle size. Furthermore, the grafted PGMA content on the magnetic nanoparticles could be controlled by varying the ligand to transition metal ratio in a N,N,N‧,N″,N″-pentamethyldiethylenetriamine (PMDETA)/CuBr2 catalyst system. The maximum grafted content was 23.1% at a ratio of [PMDETA]0/[CuBr2]0 = 2:1.

  11. REACTOR CONTROL

    DOEpatents

    Ruano, W.J.

    1957-12-10

    This patent relates to nuclear reactors of the type which utilize elongited rod type fuel elements immersed in a liquid moderator and shows a design whereby control of the chain reaction is obtained by varying the amount of moderator or reflector material. A central tank for containing liquid moderator and fuel elements immersed therein is disposed within a surrounding outer tank providing an annular space between the two tanks. This annular space is filled with liquid moderator which functions as a reflector to reflect neutrons back into the central reactor tank to increase the reproduction ratio. Means are provided for circulating and cooling the moderator material in both tanks and additional means are provided for controlling separately the volume of moderator in each tank, which latter means may be operated automatically by a neutron density monitoring device. The patent also shows an arrangement for controlling the chain reaction by injecting and varying an amount of poisoning material in the moderator used in the reflector portion of the reactor.

  12. EPR studies of a new family of organic conductors: Dimethyl(ethylenedithio)diselenadithiafulvalene compounds (DMET)2X [X=PF6, BF4, Au(CN)2, I3, and AuBr2

    NASA Astrophysics Data System (ADS)

    Kanoda, Kazushi; Takahashi, Toshihiro; Kikuchi, Koichi; Saito, Kazuya; Ikemoto, Isao; Kobayashi, Keiji

    1989-03-01

    A new family of organic conductors dimethyl(ethylenedithio)diselenadithiafulvalene compounds (DMET)2X [X=PF6, BF4, Au(CN)2, I3, and AuBr2] has been investigated by means of EPR. In spite of the large variety of conductive behaviors ranging from insulator to metal, the spin susceptibility at higher temperatures was found to be quite similar in magnitude and in temperature dependence for all the salts (except the AuBr2 salt). Below 20-25 K, the first three salts are found to undergo phase transitions; the transitions in the BF4 and Au(CN)2 salts are clearly magnetic, i.e., an antiferromagnetic or spin-density-wave transition. In the PF6 salt, EPR properties suggest a possible spin-Peierls transition. The I3 and AuBr2 salts have no EPR anomaly in the measured temperature region. The difference in the EPR linewidth among these salts is well understood as a result of the variation of dimensionality, in the framework of the Elliott mechanism. The DMET family contains all the electronic features observed in the tetramethyltetrathiafulvalene, tetramethyl- tetraselenafulvalene and bis(ethylenedithio)-tetrathiafulvalene families.

  13. High-Throughput Synthesis of Lignin Particles (∼30 nm to ∼2 μm) via Aerosol Flow Reactor: Size Fractionation and Utilization in Pickering Emulsions.

    PubMed

    Ago, Mariko; Huan, Siqi; Borghei, Maryam; Raula, Janne; Kauppinen, Esko I; Rojas, Orlando J

    2016-09-01

    An aerosol flow reactor was used for the first time for high-throughput, high yield synthesis of spherical lignin particles with given inherent hydrophilicity, depending on the precursor biomolecule. In situ fractionation via Berner type impactor afforded populations with characteristic sizes ranging from ∼30 nm to 2 μm. The as-produced, dry lignin particles displayed excellent mechanical integrity, even after redispersion under high shear in either mineral oil or water. They were effective in the stabilization of oil-in-water (O/W) Pickering emulsions with tunable droplet size, depending on the dimension of the lignin particles used for emulsification. The emulsion stability correlated with particle concentration as well as the respective lignin type. For the O/W emulsions stabilized with the more hydrophilic lignin particles, negligible changes in phase separation via Ostwald ripening and coalescence were observed over a period of time of more than two months. Together with the fact that the lignin particle concentrations used in emulsification were as low as 0.1%, our results reveal a remarkable ability to endow emulsified systems with high colloidal stability. Overall, we offer a new, high-yield, scalable nanomanufacturing approach to producing dry spherical lignin particles with size control and high production capacity. A number of emerging applications for these organic particles can be envisioned and, as a proof-of-concept, we illustrate here surfactant-free emulsification. PMID:27538013

  14. Nuclear reactor apparatus

    DOEpatents

    Wade, Elman E.

    1978-01-01

    A lifting, rotating and sealing apparatus for nuclear reactors utilizing rotating plugs above the nuclear reactor core. This apparatus permits rotation of the plugs to provide under the plug refueling of a nuclear core. It also provides a means by which positive top core holddown can be utilized. Both of these operations are accomplished by means of the apparatus lifting the top core holddown structure off the nuclear core while stationary, and maintaining this structure in its elevated position during plug rotation. During both of these operations, the interface between the rotating member and its supporting member is sealingly maintained.

  15. 2D numerical modelling of the gas temperature in a high-temperature high-power strontium atom laser excited by nanosecond pulsed longitudinal discharge in a He-SrBr2 mixture

    NASA Astrophysics Data System (ADS)

    Chernogorova, T. P.; Temelkov, K. A.; Koleva, N. K.; Vuchkov, N. K.

    2014-05-01

    Assuming axial symmetry and a uniform power input, a 2D model (r, z) is developed numerically for determination of the gas temperature in the case of a nanosecond pulsed longitudinal discharge in He-SrBr2 formed in a newly-designed large-volume high-temperature discharge tube with additional incompact ZrO2 insulation in the discharge-free zone, in order to find the optimal thermal mode for achievement of maximal output laser parameters. The model determines the gas temperature of a nanosecond pulsed longitudinal discharge in helium with small additives of strontium and bromine.

  16. NEUTRONIC REACTOR

    DOEpatents

    Fermi, E.; Zinn, W.H.; Anderson, H.L.

    1958-09-16

    Means are presenied for increasing the reproduction ratio of a gaphite- moderated neutronic reactor by diminishing the neutron loss due to absorption or capture by gaseous impurities within the reactor. This means comprised of a fluid-tight casing or envelope completely enclosing the reactor and provided with a valve through which the casing, and thereby the reactor, may be evacuated of atmospheric air.

  17. Heterometallic aggregates of copper(I) with metalloligand Sn(edt)2 (edt = ethane-1,2-dithiolate): syntheses and structures of [Sn(edt)2Cl(mu-I)(mu3-I)(CuPPh3)3], [Sn(edt)2(mu-Br)2(mu3-Br)2(CuPPh3)4], and [{Sn(edt)2}3(mu-OH)3Cu5(PPh3)8][PF6]2.

    PubMed

    Han, Yan-Gong; Xu, Chao; Duan, Taike; Wu, Fang-Hui; Zhang, Qian-Feng; Leung, Wa-Hung

    2009-09-21

    The treatment of a slurry of an equimolar mixture of [Sn(edt)(2)] (edt = ethane-1,2- dithiolate) and [Et(4)N]Cl.xH(2)O with CuI in the presence of PPh(3) gave a tetranuclear compound, [Sn(edt)(2)Cl(mu-I)(mu(3)-I)(CuPPh(3))(3)] (1), which consists of a rectangular-pyramidal [Sn(edt)(2)Cl](-) moiety ligated by three [Cu(PPh(3))](+) fragments via the sulfur atoms of the edt(2-) ligands. The treatment of a slurry of [Sn(edt)(2)] and excess [Et(4)N]Br with [Cu(MeCN)(4)][PF(6)] in the presence of PPh(3) afforded a pentanuclear compound, [Sn(edt)(2)(mu-Br)(2)(mu(3)-Br)(2)(CuPPh(3))(4)] (2), which comprises two [(CuPPh(3))(2)(mu-Br)](+) fragments symmetrically ligating an octahedral trans-[Sn(edt)(2)Br(2)](2-) moiety via the sulfur and bromide atoms. Reaction of [Sn(edt)(2)] with [Cu(MeCN)(4)][PF(6)] and PPh(3) in a mixed MeCN/CH(2)Cl(2) solution yielded a novel octanuclear compound, [{Sn(edt)(2)}(3)(mu-OH)(3)Cu(5)(PPh(3))(8)][PF(6)](2) (3), which may be described as a triangular [{Sn(edt)(2)}(3)(mu-OH)(3)](3-) core chelated by three [Cu(PPh(3))(2)](+) species and capped by two [Cu(PPh(3))](+) species. The luminescent properties of compounds 1, 2, and 3 were investigated in a CH(2)Cl(2) solution at room temperature. Upon excitation at lambda > 360 nm, these compounds are luminescent in CH(2)Cl(2) solution with emissions having maxima at 422, 515, and 494 nm, respectively. PMID:19746999

  18. Development of refined MCNPX-PARET multi-channel model for transient analysis in research reactors

    SciTech Connect

    Kalcheva, S.; Koonen, E.; Olson, A. P.

    2012-07-01

    Reactivity insertion transients are often analyzed (RELAP, PARET) using a two-channel model, representing the hot assembly with specified power distribution and an average assembly representing the remainder of the core. For the analysis of protected by the reactor safety system transients and zero reactivity feedback coefficients this approximation proves to give adequate results. However, a more refined multi-channel model representing the various assemblies, coupled through the reactivity feedback effects to the whole reactor core is needed for the analysis of unprotected transients with excluded over power and period trips. In the present paper a detailed multi-channel PARET model has been developed which describes the reactor core in different clusters representing typical BR2 fuel assemblies. The distribution of power and reactivity feedback in each cluster of the reactor core is obtained from a best-estimate MCNPX calculation using the whole core geometry model of the BR2 reactor. The sensitivity of the reactor response to power, temperature and energy distributions is studied for protected and unprotected reactivity insertion transients, with zero and non-zero reactivity feedback coefficients. The detailed multi-channel model is compared vs. simplified fewer-channel models. The sensitivities of transient characteristics derived from the different models are tested on a few reactivity insertion transients with reactivity feedback from coolant temperature and density change. (authors)

  19. Irradiation performance of (Th,Pu)O2 fuel under Pressurized Water Reactor conditions

    NASA Astrophysics Data System (ADS)

    Boer, B.; Lemehov, S.; Wéber, M.; Parthoens, Y.; Gysemans, M.; McGinley, J.; Somers, J.; Verwerft, M.

    2016-04-01

    This paper examines the in-pile safety performance of (Th,Pu)O2 fuel pins under simulated Pressurized Water Reactor (PWR) conditions. Both sol-gel and SOLMAS produced (Th,Pu)O2 fuels at enrichments of 7.9% and 12.8% in Pu/HM have been irradiated at SCK·CEN. The irradiation has been performed under PWR conditions (155 bar, 300 °C) in a dedicated loop of the BR-2 reactor. The loop is instrumented with flow and temperature monitors at inlet and outlet, which allow for an accurate measurement of the deposited enthalpy.

  20. Space reactor shielding fabrication

    NASA Technical Reports Server (NTRS)

    Welch, F. H.

    1972-01-01

    The fabrication of space reactor neutron shielding by a melting and casting process utilizing lithium hydride is described. The first neutron shield fabricated is a large pancake shape 86 inches in diameter, containing about 1700 pounds of lithium hydride. This shield, fabricated by the unique melting and casting process, is the largest lithium hydride shield ever built.

  1. NUCLEAR REACTOR FUEL ELEMENT

    DOEpatents

    Currier, E.L. Jr.; Nicklas, J.H.

    1963-06-11

    A fuel plate is designed for incorporation into control rods of the type utilized in high-flux test reactors. The fuel plate is designed so that the portion nearest the poison section of the control rod contains about one-half as much fissionable material as in the rest of the plate, thereby eliminating dangerous flux peaking in that portion. (AEC)

  2. BOILING REACTORS

    DOEpatents

    Untermyer, S.

    1962-04-10

    A boiling reactor having a reactivity which is reduced by an increase in the volume of vaporized coolant therein is described. In this system unvaporized liquid coolant is extracted from the reactor, heat is extracted therefrom, and it is returned to the reactor as sub-cooled liquid coolant. This reduces a portion of the coolant which includes vaporized coolant within the core assembly thereby enhancing the power output of the assembly and rendering the reactor substantially self-regulating. (AEC)

  3. NEUTRONIC REACTOR

    DOEpatents

    Daniels, F.

    1959-10-27

    A reactor in which at least a portion of the moderator is in the form of movable refractory balls is described. In addition to their moderating capacity, these balls may serve as carriers for fissionable material or fertile material, or may serve in a coolant capacity to remove heat from the reactor. A pneumatic system is used to circulate the balls through the reactor.

  4. Persistence of singlet fluctuations in the coupled spin tetrahedra system Cu2Te2O5Br2 revealed by high-field magnetization, 79Br NQR, and 125Te NMR

    NASA Astrophysics Data System (ADS)

    Baek, S.-H.; Choi, K.-Y.; Berger, H.; Büchner, B.; Grafe, H.-J.

    2012-11-01

    We present high-field magnetization and 79Br nuclear quadrupole resonance (NQR) and 125Te nuclear magnetic resonance (NMR) studies in the weakly coupled Cu2+ (S=1/2) tetrahedral system Cu2Te2O5Br2. The field-induced level crossing effects were observed by the magnetization measurements in a long-ranged magnetically ordered state which was confirmed by a strong divergence of the spin-lattice relaxation rate T1-1 at T0=13.5 K. In the paramagnetic state, T1-1 reveals an effective singlet-triplet spin gap much larger than that observed by static bulk measurements. Our results imply that the inter- and the intratetrahedral interactions compete, but at the same time they cooperate strengthening effectively the local intratetrahedral exchange couplings. We discuss that the unusual feature originates from the frustrated intertetrahedral interactions.

  5. 2D numerical modelling of gas temperature in a nanosecond pulsed longitudinal He-SrBr2 discharge excited in a high temperature gas-discharge tube for the high-power strontium laser

    NASA Astrophysics Data System (ADS)

    Chernogorova, T. P.; Temelkov, K. A.; Koleva, N. K.; Vuchkov, N. K.

    2016-05-01

    An active volume scaling in bore and length of a Sr atom laser excited in a nanosecond pulse longitudinal He-SrBr2 discharge is carried out. Considering axial symmetry and uniform power input, a 2D model (r, z) is developed by numerical methods for determination of gas temperature in a new large-volume high-temperature discharge tube with additional incompact ZrO2 insulation in the discharge free zone, in order to find out the optimal thermal mode for achievement of maximal output laser parameters. A 2D model (r, z) of gas temperature is developed by numerical methods for axial symmetry and uniform power input. The model determines gas temperature of nanosecond pulsed longitudinal discharge in helium with small additives of strontium and bromine.

  6. Research reactors

    SciTech Connect

    Tonneson, L.C.; Fox, G.J.

    1996-04-01

    There are currently 284 research reactors in operation, and 12 under construction around the world. Of the operating reactors, nearly two-thirds are used exclusively for research, and the rest for a variety of purposes, including training, testing, and critical assembly. For more than 50 years, research reactor programs have contributed greatly to the scientific and educational communities. Today, six of the world`s research reactors are being shut down, three of which are in the USA. With government budget constraints and the growing proliferation concerns surrounding the use of highly enriched uranium in some of these reactors, the future of nuclear research could be impacted.

  7. Labview utilities

    Energy Science and Technology Software Center (ESTSC)

    2011-09-30

    The software package provides several utilities written in LabView. These utilities don't form independent programs, but rather can be used as a library or controls in other labview programs. The utilities include several new controls (xcontrols), VIs for input and output routines, as well as other 'helper'-functions not provided in the standard LabView environment.

  8. NEUTRONIC REACTOR

    DOEpatents

    Fraas, A.P.; Mills, C.B.

    1961-11-21

    A neutronic reactor in which neutron moderation is achieved primarily in its reflector is described. The reactor structure consists of a cylindrical central "island" of moderator and a spherical moderating reflector spaced therefrom, thereby providing an annular space. An essentially unmoderated liquid fuel is continuously passed through the annular space and undergoes fission while contained therein. The reactor, because of its small size, is particularly adapted for propulsion uses, including the propulsion of aircraft. (AEC)

  9. REACTOR COOLING

    DOEpatents

    Quackenbush, C.F.

    1959-09-29

    A nuclear reactor with provisions for selectively cooling the fuel elements is described. The reactor has a plurality of tubes extending throughout. Cylindrical fuel elements are disposed within the tubes and the coolant flows through the tubes and around the fuel elements. The fuel elements within the central portion of the reactor are provided with roughened surfaces of material. The fuel elements in the end portions of the tubes within the reactor are provlded with low conduction jackets and the fuel elements in the region between the central portion and the end portions are provided with smooth surfaces of high heat conduction material.

  10. Cermet fuel reactors

    SciTech Connect

    Cowan, C.L.; Palmer, R.S.; Van Hoomissen, J.E.; Bhattacharyya, S.K.; Barner, J.O.

    1987-09-01

    Cermet fueled nuclear reactors are attractive candidates for high performance space power systems. The cermet fuel consists of tungsten-urania hexagonal fuel blocks characterized by high strength at elevated temperatures, a high thermal conductivity and resultant high thermal shock resistance. Key features of the cermet fueled reactor design are (1) the ability to achieve very high coolant exit temperatures, and (2) thermal shock resistance during rapid power changes, and (3) two barriers to fission product release - the cermet matrix and the fuel element cladding. Additionally, thre is a potential for achieving a long operating life because of (1) the neutronic insensitivity of the fast-spectrum core to the buildup of fission products and (2) the utilization of a high strength refractory metal matrix and structural materials. These materials also provide resistance against compression forces that potentially might compact and/or reconfigure the core. In addition, the neutronic properties of the refractory materials assure that the reactor remains substantially subcritical under conditions of water immersion. It is concluded that cermet fueled reactors can be utilized to meet the power requirements for a broad range of advanced space applications. 4 refs., 4 figs., 3 tabs.

  11. WATER BOILER REACTOR

    DOEpatents

    King, L.D.P.

    1960-11-22

    As its name implies, this reactor utilizes an aqueous solution of a fissionable element salt, and is also conventional in that it contains a heat exchanger cooling coil immersed in the fuel. Its novelty lies in the utilization of a cylindrical reactor vessel to provide a critical region having a large and constant interface with a supernatant vapor region, and the use of a hollow sleeve coolant member suspended from the cover assembly in coaxial relation with the reactor vessel. Cool water is circulated inside this hollow coolant member, and a gap between its outer wall and the reactor vessel is used to carry off radiolytic gases for recombination in an external catalyst chamber. The central passage of the coolant member defines a reflux condenser passage into which the externally recombined gases are returned and condensed. The large and constant interface between fuel solution and vapor region prevents the formation of large bubbles and minimizes the amount of fuel salt carried off by water vapor, thus making possible higher flux densities, specific powers and power densities.

  12. Fissioning Plasma Core Reactor

    NASA Technical Reports Server (NTRS)

    Albright, Dennis; Butler, Carey; West, Nicole; Cole, John W. (Technical Monitor)

    2002-01-01

    Institute for Scientific Research, Inc. (ISR) research program consist of: 1.Study core physics by adapting existing codes: MCNP4C - Monte Carlo code; COMBINE/VENTURE - diffusion theory; SCALE4 - Monte Carlo, with many utility codes. 2. Determine feasibility and study major design parameters: fuel selection, temperature and reflector sizing. 3. Study reactor kinetics: develop QCALC1 to model point kinetics; study dynamic behavior of the power release.

  13. Light-induced structural changes in (HgBr2)3(As4S4)2: An X-ray single-crystal diffraction, Raman spectroscopy and ab initio study

    NASA Astrophysics Data System (ADS)

    Zoppi, M.; Bindi, L.; Rödl, T.; Pielnhofer, F.; Weihrich, R.; Pfitzner, A.; Bonazzi, P.

    2013-09-01

    To investigate the behaviour of the As4S4 molecule within a crystal-chemical environment differing from realgar, α-As4S4, and its high-temperature polymorph, β-As4S4, the effects of the light exposure on the structure of the (HgBr2)3(As4S4)2 adduct have been studied. Differently from the cases previously studied, the action of the light filtered using a 550 nm long-wavelength pass filter did not produce any evident effect on the unit-cell. On the other hand, employing the 440 nm long-wavelength pass filter, remarkable variations of the unit-cell parameters were observed. In particular, an increase of the a, c, and β, and a decrease of the b parameter, producing on the whole an expansion of the unit-cell volume, is observed as a function of the light exposure times. Structure refinements indicated that the increase of the unit-cell volume is to ascribe to the formation of an increasing fraction (up to 20%) of pararealgar-type replacing the realgar-type molecule. Further light-exposure did not cause any further increase of the lattice parameters. On the contrary, a decrease of the unit-cell volume occurred by keeping the crystal in the dark (46 days): due to the loss of the crystallinity, only the core of the crystal, less altered and with smaller unit-cell volume, contributes to the diffraction effects. Micro-Raman spectra were collected on crystals exposed to the above mentioned wavelength light for increasing times. The peak at 275(±1) cm-1 whose intensity increases as a function of the exposure time confirms the transition from a realgar- to a pararealgar-type molecule in the (HgBr2)3(As4S4)2 adduct. Relativistic DFT-GGA ab initio band structure calculations reveal a direct band gap of 2.04 eV and quite flat valence and conduction bands around the Fermi level. According to analyses of the atomic orbital contributions to the electronic band structures the highest occupied states are attributed to non-bonding p-states of As.

  14. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.

    1958-04-22

    A nuclear reactor for isotope production is described. This reactor is designed to provide a maximum thermal neutron flux in a region adjacent to the periphery of the reactor rather than in the center of the reactor. The core of the reactor is generally centrally located with respect tn a surrounding first reflector, constructed of beryllium. The beryllium reflector is surrounded by a second reflector, constructed of graphite, which, in tune, is surrounded by a conventional thermal shield. Water is circulated through the core and the reflector and functions both as a moderator and a coolant. In order to produce a greatsr maximum thermal neutron flux adjacent to the periphery of the reactor rather than in the core, the reactor is designed so tbat the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the materials in the reflector is approximately twice the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the material of the core of the reactor.

  15. NEUTRONIC REACTOR

    DOEpatents

    Metcalf, H.E.; Johnson, H.W.

    1961-04-01

    BS>A nuclear reactor incorporating fuel rods passing through a moderator and including tubes of a material of higher Thermal conductivity than the fuel in contact with the fuel is described. The tubes extend beyond the active portion of the reactor into contant with a fiuld coolant.

  16. Compact heat and mass exchangers of the plate fin type in thermal sorption systems: Application in an absorption heat pump with the working pair CH3OH-LiBr/ZnBr2

    NASA Astrophysics Data System (ADS)

    Becker, Harry

    The possible application of Compact Heat and Mass Exchangers (CHME) in a gas fired Absorption Heat Pump (AHP) for domestic heating is studied. The above mentioned heat and mass exchangers are of the plate type. The space between the parallel and plain plates is filled up with corrugated plates of a certain height. The plain and finned plates are stacked and welded together. This gives a heat and mass exchanger which is very compact, expressed by a high area density (m2/m3). This leads to heat and mass transfer processes with small temperature and concentration differences. For testing purposes a pilot plant was built using the above type of components in order to test their heat and/or mass transfer performance. Only the generator is of the Shell And Tube (SAT) type. As the working pair, CH3OH - LiBr/ ZnBr2 was chosen, with the alcohol as the solvent and the salt mixture as the absorbent. This leads to sub atmospheric working pressures with only solvent in the vapor phase. Three series of experiments have been carried out, during which the input parameters were varied over a certain range. It is concluded that the plate fin CHMES are very suitable for application in an AHP for domestic heating purposes.

  17. A novel 3D Cu(I) coordination polymer based on Cu6Br2 and Cu2(CN)2 SBUs: in situ ligand formation and use as a naked-eye colorimetric sensor for NB and 2-NT.

    PubMed

    Song, Jiang-Feng; Li, Yang; Zhou, Rui-Sha; Hu, Tuo-Ping; Wen, Yan-Liang; Shao, Jia; Cui, Xiao-Bing

    2016-01-14

    A novel coordination polymer with the chemical formula [Cu4Br(CN)(mtz)2]n (mtz = 5-methyl tetrazole) (), has been synthesized under solvothermal conditions and characterized by elemental analysis, infrared (IR) spectroscopy, thermal gravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. Interestingly, the Cu(i), CN(-) and mtz(-) in compound are all generated from an in situ translation of the original precursors: Cu(2+), acetonitrile and 1-methyl-5-mercapto-1,2,3,4-tetrazole (Hmnt). The in situ ring-to-ring conversion of Hmnt into mtz(-) was found for the first time. Structural analysis reveals that compound is a novel 3D tetrazole-based Cu(i) coordination polymer, containing both metal halide cluster Cu6Br2 and metal pseudohalide cluster Cu2(CN)2 secondary building units (SBUs), which shows an unprecedented (3,6,10)-connected topology. Notably, a pseudo-porphyrin structure with 16-membered rings constructed by four mtz(-) anions and four copper(i) ions was observed in compound . The fluorescence properties of compound were investigated in the solid state and in various solvent emulsions, the results show that compound is a highly sensitive naked-eye colorimetric sensor for NB and 2-NT (NB = nitrobenzene and 2-NT = 2-nitrotoluene). PMID:26600452

  18. Compact Reactor

    SciTech Connect

    Williams, Pharis E.

    2007-01-30

    Weyl's Gauge Principle of 1929 has been used to establish Weyl's Quantum Principle (WQP) that requires that the Weyl scale factor should be unity. It has been shown that the WQP requires the following: quantum mechanics must be used to determine system states; the electrostatic potential must be non-singular and quantified; interactions between particles with different electric charges (i.e. electron and proton) do not obey Newton's Third Law at sub-nuclear separations, and nuclear particles may be much different than expected using the standard model. The above WQP requirements lead to a potential fusion reactor wherein deuterium nuclei are preferentially fused into helium nuclei. Because the deuterium nuclei are preferentially fused into helium nuclei at temperatures and energies lower than specified by the standard model there is no harmful radiation as a byproduct of this fusion process. Therefore, a reactor using this reaction does not need any shielding to contain such radiation. The energy released from each reaction and the absence of shielding makes the deuterium-plus-deuterium-to-helium (DDH) reactor very compact when compared to other reactors, both fission and fusion types. Moreover, the potential energy output per reactor weight and the absence of harmful radiation makes the DDH reactor an ideal candidate for space power. The logic is summarized by which the WQP requires the above conditions that make the prediction of DDH possible. The details of the DDH reaction will be presented along with the specifics of why the DDH reactor may be made to cause two deuterium nuclei to preferentially fuse to a helium nucleus. The presentation will also indicate the calculations needed to predict the reactor temperature as a function of fuel loading, reactor size, and desired output and will include the progress achieved to date.

  19. NUCLEAR REACTOR

    DOEpatents

    Moore, R.V.; Bowen, J.H.; Dent, K.H.

    1958-12-01

    A heterogeneous, natural uranium fueled, solid moderated, gas cooled reactor is described, in which the fuel elements are in the form of elongated rods and are dlsposed within vertical coolant channels ln the moderator symmetrically arranged as a regular lattice in groups. This reactor employs control rods which operate in vertical channels in the moderator so that each control rod is centered in one of the fuel element groups. The reactor is enclosed in a pressure vessel which ls provided with access holes at the top to facilitate loading and unloadlng of the fuel elements, control rods and control rod driving devices.

  20. NEUTRONIC REACTOR

    DOEpatents

    Anderson, H.L.

    1960-09-20

    A nuclear reactor is described comprising fissionable material dispersed in graphite blocks, helium filling the voids of the blocks and the spaces therebetween, and means other than the helium in thermal conductive contact with the graphite for removing heat.

  1. NEUTRONIC REACTOR

    DOEpatents

    Hurwitz, H. Jr.; Brooks, H.; Mannal, C.; Payne, J.H.; Luebke, E.A.

    1959-03-24

    A reactor of the heterogeneous, liquid cooled type is described. This reactor is comprised of a central region of a plurality of vertically disposed elongated tubes surrounded by a region of moderator material. The central region is comprised of a central core surrounded by a reflector region which is surrounded by a fast neutron absorber region, which in turn is surrounded by a slow neutron absorber region. Liquid sodium is used as the primary coolant and circulates through the core which contains the fuel elements. Control of the reactor is accomplished by varying the ability of the reflector region to reflect neutrons back into the core of the reactor. For this purpose the reflector is comprised of moderator and control elements having varying effects on reactivity, the control elements being arranged and actuated by groups to give regulation, shim, and safety control.

  2. NUCLEAR REACTOR

    DOEpatents

    Sherman, J.; Sharbaugh, J.E.; Fauth, W.L. Jr.; Palladino, N.J.; DeHuff, P.G.

    1962-10-23

    A nuclear reactor incorporating seed and blanket assemblies is designed. Means are provided for obtaining samples of the coolant from the blanket assemblies and for varying the flow of coolant through the blanket assemblies. (AEC)

  3. REACTOR SHIELD

    DOEpatents

    Wigner, E.P.; Ohlinger, L.E.; Young, G.J.; Weinberg, A.M.

    1959-02-17

    Radiation shield construction is described for a nuclear reactor. The shield is comprised of a plurality of steel plates arranged in parallel spaced relationship within a peripheral shell. Reactor coolant inlet tubes extend at right angles through the plates and baffles are arranged between the plates at right angles thereto and extend between the tubes to create a series of zigzag channels between the plates for the circulation of coolant fluid through the shield. The shield may be divided into two main sections; an inner section adjacent the reactor container and an outer section spaced therefrom. Coolant through the first section may be circulated at a faster rate than coolant circulated through the outer section since the area closest to the reactor container is at a higher temperature and is more radioactive. The two sections may have separate cooling systems to prevent the coolant in the outer section from mixing with the more contaminated coolant in the inner section.

  4. NUCLEAR REACTOR

    DOEpatents

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

    1958-01-21

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

  5. NEUTRONIC REACTOR

    DOEpatents

    Fermi, E.

    1960-04-01

    A nuclear reactor is described consisting of blocks of graphite arranged in layers, natural uranium bodies disposed in holes in alternate layers of graphite blocks, and coolant tubes disposed in the layers of graphite blocks which do not contain uranium.

  6. NUCLEAR REACTOR

    DOEpatents

    Anderson, C.R.

    1962-07-24

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

  7. NUCLEAR REACTOR

    DOEpatents

    Breden, C.R.; Dietrich, J.R.

    1961-06-20

    A water-soluble non-volatile poison may be introduced into a reactor to nullify excess reactivity. The poison is removed by passing a side stream of the water containing the soluble poison to an evaporation chamber. The vapor phase is returned to the reactor to decrease the concentration of soluble poison and the liquid phase is returned to increase the concentration of soluble poison.

  8. EMERGING TECHNOLOGY BULLETIN: SPOUTED BED REACTOR

    EPA Science Inventory

    The Spouted Bed Reactor (SBR) technology utilizes the unique attributes of the "spouting " fluidization regime, which can provide heat transfer rates comparable to traditional fluid beds, while providing robust circulation of highly heterogeneous solids, concurrent with very agg...

  9. A Computer Code for TRIGA Type Reactors.

    Energy Science and Technology Software Center (ESTSC)

    1992-04-09

    Version 00 TRIGAP was developed for reactor physics calculations of the 250 kW TRIGA reactor. The program can be used for criticality predictions, power peaking predictions, fuel element burn-up calculations and data logging, and in-core fuel management and fuel utilization improvement.

  10. On reactor type comparisons for the next generation of reactors

    SciTech Connect

    Alesso, H.P.; Majumdar, K.C.

    1991-08-22

    In this paper, we present a broad comparison of studies for a selected set of parameters for different nuclear reactor types including the next generation. This serves as an overview of key parameters which provide a semi-quantitative decision basis for selecting nuclear strategies. Out of a number of advanced reactor designs of the LWR type, gas cooled type, and FBR type, currently on the drawing board, the Advanced Light Water Reactors (ALWR) seem to have some edge over other types of the next generation of reactors for the near-term application. This is based on a number of attributes related to the benefit of the vast operating experience with LWRs coupled with an estimated low risk profile, economics of scale, degree of utilization of passive systems, simplification in the plant design and layout, modular fabrication and manufacturing. 32 refs., 1 fig., 3 tabs.

  11. Research reactors - an overview

    SciTech Connect

    West, C.D.

    1997-03-01

    A broad overview of different types of research and type reactors is provided in this paper. Reactor designs and operating conditions are briefly described for four reactors. The reactor types described include swimming pool reactors, the High Flux Isotope Reactor, the Mark I TRIGA reactor, and the Advanced Neutron Source reactor. Emphasis in the descriptions is placed on safety-related features of the reactors. 7 refs., 7 figs., 2 tabs.

  12. BIOMASS UTILIZATION

    EPA Science Inventory

    The biomass utilization task consists of the evaluation of a biomass conversion technology including research and development initiatives. The project is expected to provide information on co-control of pollutants, as well as, to prove the feasibility of biomass conversion techn...

  13. Lighting Utilization.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with lighting utilization. Its objective is for the student to be able to outline the development of lighting use and conservation and identify major types and operating characteristics of lamps used in electric lighting. Some topics…

  14. NEUTRONIC REACTOR CORE INSTRUMENT

    DOEpatents

    Mims, L.S.

    1961-08-22

    A multi-purpose instrument for measuring neutron flux, coolant flow rate, and coolant temperature in a nuclear reactor is described. The device consists essentially of a hollow thimble containing a heat conducting element protruding from the inner wall, the element containing on its innermost end an amount of fissionsble materinl to function as a heat source when subjected to neutron flux irradiation. Thermocouple type temperature sensing means are placed on the heat conducting element adjacent the fissionable material and at a point spaced therefrom, and at a point on the thimble which is in contact with the coolant fluid. The temperature differentials measured between the thermocouples are determinative of the neutron flux, coolant flow, and temperature being measured. The device may be utilized as a probe or may be incorporated in a reactor core. (AE C)

  15. NEUTRONIC REACTOR

    DOEpatents

    Ohlinger, L.A.; Wigner, E.P.; Weinberg, A.M.; Young, G.J.

    1958-09-01

    This patent relates to neutronic reactors of the heterogeneous water cooled type, and in particular to a fuel element charging and discharging means therefor. In the embodiment illustrated the reactor contains horizontal, parallel coolant tubes in which the fuel elements are disposed. A loading cart containing a magnzine for holding a plurality of fuel elements operates along the face of the reactor at the inlet ends of the coolant tubes. The loading cart is equipped with a ram device for feeding fuel elements from the magazine through the inlot ends of the coolant tubes. Operating along the face adjacent the discharge ends of the tubes there is provided another cart means adapted to receive irradiated fuel elements as they are forced out of the discharge ends of the coolant tubes by the incoming new fuel elements. This cart is equipped with a tank coataining a coolant, such as water, into which the fuel elements fall, and a hydraulically operated plunger to hold the end of the fuel element being discharged. This inveation provides an apparatus whereby the fuel elements may be loaded into the reactor, irradiated therein, and unloaded from the reactor without stopping the fiow of the coolant and without danger to the operating personnel.

  16. METHOD OF OPERATING NUCLEAR REACTORS

    DOEpatents

    Untermyer, S.

    1958-10-14

    A method is presented for obtaining enhanced utilization of natural uranium in heavy water moderated nuclear reactors by charging the reactor with an equal number of fuel elements formed of natural uranium and of fuel elements formed of uranium depleted in U/sup 235/ to the extent that the combination will just support a chain reaction. The reactor is operated until the rate of burnup of plutonium equals its rate of production, the fuel elements are processed to recover plutonium, the depleted uranium is discarded, and the remaining uranium is formed into fuel elements. These fuel elements are charged into a reactor along with an equal number of fuel elements formed of uranium depleted in U/sup 235/ to the extent that the combination will just support a chain reaction, and reuse of the uranium is continued as aforesaid until it wlll no longer support a chain reaction when combined with an equal quantity of natural uranium.

  17. Microchannel Reactors for ISRU Applications

    NASA Astrophysics Data System (ADS)

    Carranza, Susana; Makel, Darby B.; Blizman, Brandon; Ward, Benjamin J.

    2005-02-01

    Affordable planning and execution of prolonged manned space missions depend upon the utilization of local resources and the waste products which are formed in manned spacecraft and surface bases. Successful in-situ resources utilization (ISRU) will require component technologies which provide optimal size, weight, volume, and power efficiency. Microchannel reactors enable the efficient chemical processing of in situ resources. The reactors can be designed for the processes that generate the most benefit for each mission. For instance, propellants (methane) can be produced from carbon dioxide from the Mars atmosphere using the Sabatier reaction and ethylene can be produced from the partial oxidation of methane. A system that synthesizes ethylene could be the precursor for systems to synthesize ethanol and polyethylene. Ethanol can be used as a nutrient for Astrobiology experiments, as well as the production of nutrients for human crew (e.g. sugars). Polyethylene can be used in the construction of habitats, tools, and replacement parts. This paper will present recent developments in miniature chemical reactors using advanced Micro Electro Mechanical Systems (MEMS) and microchannel technology to support ISRU of Mars and lunar missions. Among other applications, the technology has been demonstrated for the Sabatier process and for the partial oxidation of methane. Microchannel reactors were developed based on ceramic substrates as well as metal substrates. In both types of reactors, multiple layers coated with catalytic material are bonded, forming a monolithic structure. Such reactors are readily scalable with the incorporation of extra layers. In addition, this reactor structure minimizes pressure drop and catalyst settling, which are common problems in conventional packed bed reactors.

  18. NUCLEAR REACTOR

    DOEpatents

    Christy, R.F.

    1958-07-15

    A nuclear reactor of the homogeneous liquid fuel type is described wherein the fissionable isotope is suspended or dissolved in a liquid moderator such as water. The reactor core is comprised essentially of a spherical vessel for containing the reactive composition surrounded by a reflector, preferably of beryllium oxide. The reactive composition may be an ordinary water solution of a soluble salt of uranium, the quantity of fissionable isotope in solution being sufficient to provide a critical mass in the vessel. The liquid fuel is stored in a tank of non-crtttcal geometry below the reactor vessel and outside of the reflector and is passed from the tank to the vessel through a pipe connecting the two by air pressure means. Neutron absorbing control and safety rods are operated within slots in the reflector adjacent to the vessel.

  19. NEUTRONIC REACTORS

    DOEpatents

    Wigner, E.P.; Young, G.J.

    1958-10-14

    A method is presented for loading and unloading rod type fuel elements of a neutronic reactor of the heterogeneous, solld moderator, liquid cooled type. In the embodiment illustrated, the fuel rods are disposed in vertical coolant channels in the reactor core. The fuel rods are loaded and unloaded through the upper openings of the channels which are immersed in the coolant liquid, such as water. Unloading is accomplished by means of a coffer dam assembly having an outer sleeve which is placed in sealing relation around the upper opening. A radiation shield sleeve is disposed in and reciprocable through the coffer dam sleeve. A fuel rod engaging member operates through the axial bore in the radiation shield sleeve to withdraw the fuel rod from its position in the reactor coolant channel into the shield, the shield snd rod then being removed. Loading is accomplished in the reverse procedure.

  20. Catalytic reactor

    DOEpatents

    Aaron, Timothy Mark; Shah, Minish Mahendra; Jibb, Richard John

    2009-03-10

    A catalytic reactor is provided with one or more reaction zones each formed of set(s) of reaction tubes containing a catalyst to promote chemical reaction within a feed stream. The reaction tubes are of helical configuration and are arranged in a substantially coaxial relationship to form a coil-like structure. Heat exchangers and steam generators can be formed by similar tube arrangements. In such manner, the reaction zone(s) and hence, the reactor is compact and the pressure drop through components is minimized. The resultant compact form has improved heat transfer characteristics and is far easier to thermally insulate than prior art compact reactor designs. Various chemical reactions are contemplated within such coil-like structures such that as steam methane reforming followed by water-gas shift. The coil-like structures can be housed within annular chambers of a cylindrical housing that also provide flow paths for various heat exchange fluids to heat and cool components.

  1. Bioconversion reactor

    SciTech Connect

    McCarty, P.L.; Bachmann, A.

    1992-02-25

    A bioconversion reactor is described for the anaerobic fermentation of organic material. The bioconversion reactor comprises a shell enclosing a predetermined volume, an inlet port through which a liquid stream containing organic materials enters the shell, and an outlet port through which the stream exits the shell. A series of vertical and spaced-apart baffles are positioned within the shell to force the stream to flow under and over them as it passes from the inlet to the outlet port. The baffles present a barrier to the microorganisms within the shell causing them to rise and fall within the reactor but to move horizontally at a very slow rate. Treatment detention times of one day or less are possible. 7 figs.

  2. Bioconversion reactor

    DOEpatents

    McCarty, Perry L.; Bachmann, Andre

    1992-01-01

    A bioconversion reactor for the anaerobic fermentation of organic material. The bioconversion reactor comprises a shell enclosing a predetermined volume, an inlet port through which a liquid stream containing organic materials enters the shell, and an outlet port through which the stream exits the shell. A series of vertical and spaced-apart baffles are positioned within the shell to force the stream to flow under and over them as it passes from the inlet to the outlet port. The baffles present a barrier to the microorganisms within the shell causing them to rise and fall within the reactor but to move horizontally at a very slow rate. Treatment detention times of one day or less are possible.

  3. REACTOR CONTROL

    DOEpatents

    Fortescue, P.; Nicoll, D.

    1962-04-24

    A control system employed with a high pressure gas cooled reactor in which a control rod is positioned for upward and downward movement into the neutron field from a position beneath the reactor is described. The control rod is positioned by a coupled piston cylinder releasably coupled to a power drive means and the pressurized coolant is directed against the lower side of the piston. The coolant pressure is offset by a higher fiuid pressure applied to the upper surface of the piston and means are provided for releasing the higher pressure on the upper side of the piston so that the pressure of the coolant drives the piston upwardly, forcing the coupled control rod into the ncutron field of the reactor. (AEC)

  4. NUCLEAR REACTOR

    DOEpatents

    Young, G.

    1963-01-01

    This patent covers a power-producing nuclear reactor in which fuel rods of slightly enriched U are moderated by heavy water and cooled by liquid metal. The fuel rods arranged parallel to one another in a circle are contained in a large outer closed-end conduit that extends into a tank containing the heavy water. Liquid metal is introduced into the large conduit by a small inner conduit that extends within the circle of fuel rods to a point near the lower closed end of the outer conduit. (AEC) Production Reactors

  5. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.; Weinberg, A.W.; Young, G.J.

    1958-04-15

    A nuclear reactor which uses uranium in the form of elongated tubes as fuel elements and liquid as a coolant is described. Elongated tubular uranium bodies are vertically disposed in an efficient neutron slowing agent, such as graphite, for example, to form a lattice structure which is disposed between upper and lower coolant tanks. Fluid coolant tubes extend through the uranium bodies and communicate with the upper and lower tanks and serve to convey the coolant through the uranium body. The reactor is also provided with means for circulating the cooling fluid through the coolant tanks and coolant tubes, suitable neutron and gnmma ray shields, and control means.

  6. Non-equilibrium radiation nuclear reactor

    NASA Technical Reports Server (NTRS)

    Thom, K.; Schneider, R. T. (Inventor)

    1978-01-01

    An externally moderated thermal nuclear reactor is disclosed which is designed to provide output power in the form of electromagnetic radiation. The reactor is a gaseous fueled nuclear cavity reactor device which can operate over wide ranges of temperature and pressure, and which includes the capability of processing and recycling waste products such as long-lived transuranium actinides. The primary output of the device may be in the form of coherent radiation, so that the reactor may be utilized as a self-critical nuclear pumped laser.

  7. Hot Fuel Examination Facility's neutron radiography reactor

    SciTech Connect

    Pruett, D.P.; Richards, W.J.; Heidel, C.C.

    1983-01-01

    Argonne National Laboratory-West is located near Idaho Falls, Idaho, and is operated by the University of Chicago for the United States Department of Energy in support of the Liquid Metal Fast Breeder Reactor Program, LMFBR. The Hot Fuel Examination Facility, HFEF, is one of several facilities located at the Argonne Site. HFEF comprises a large hot cell where both nondestructive and destructive examination of highly-irradiated reactor fuels are conducted in support of the LMFBR program. One of the nondestructive examination techniques utilized at HFEF is neutron radiography, which is provided by the NRAD reactor facility (a TRIGA type reactor) below the HFEF hot cell.

  8. Biparticle fluidized bed reactor

    DOEpatents

    Scott, C.D.; Marasco, J.A.

    1995-04-25

    A fluidized bed reactor system utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves. 3 figs.

  9. Biparticle fluidized bed reactor

    DOEpatents

    Scott, Charles D.; Marasco, Joseph A.

    1995-01-01

    A fluidized bed reactor system utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves.

  10. Biparticle fluidized bed reactor

    DOEpatents

    Scott, Charles D.; Marasco, Joseph A.

    1996-01-01

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary and tertiary particulate phases, continuously introduced and removed simultaneously in the cocurrent and countercurrent mode, act in a role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Means for introducing and removing the sorbent phases include feed screw mechanisms and multivane slurry valves.

  11. Biparticle fluidized bed reactor

    DOEpatents

    Scott, Charles D.

    1993-01-01

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves.

  12. Biparticle fluidized bed reactor

    DOEpatents

    Scott, C.D.; Marasco, J.A.

    1996-02-27

    A fluidized bed reactor system is described which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary and tertiary particulate phases, continuously introduced and removed simultaneously in the cocurrent and countercurrent mode, act in a role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Means for introducing and removing the sorbent phases include feed screw mechanisms and multivane slurry valves. 3 figs.

  13. Biparticle fluidized bed reactor

    DOEpatents

    Scott, C.D.

    1993-12-14

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase is described. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves. 3 figures.

  14. Neutronic reactor

    DOEpatents

    Wende, Charles W. J.; Babcock, Dale F.; Menegus, Robert L.

    1983-01-01

    A nuclear reactor includes an active portion with fissionable fuel and neutron moderating material surrounded by neutron reflecting material. A control element in the active portion includes a group of movable rods constructed of neutron-absorbing material. Each rod is movable with respect to the other rods to vary the absorption of neutrons and effect control over neutron flux.

  15. Neutronic reactor

    DOEpatents

    Wende, Charles W. J.

    1976-08-17

    A safety rod for a nuclear reactor has an inner end portion having a gamma absorption coefficient and neutron capture cross section approximately equal to those of the adjacent shield, a central portion containing materials of high neutron capture cross section and an outer end portion having a gamma absorption coefficient at least equal to that of the adjacent shield.

  16. Sonochemical Reactors.

    PubMed

    Gogate, Parag R; Patil, Pankaj N

    2016-10-01

    Sonochemical reactors are based on the generation of cavitational events using ultrasound and offer immense potential for the intensification of physical and chemical processing applications. The present work presents a critical analysis of the underlying mechanisms for intensification, available reactor configurations and overview of the different applications exploited successfully, though mostly at laboratory scales. Guidelines have also been presented for optimum selection of the important operating parameters (frequency and intensity of irradiation, temperature and liquid physicochemical properties) as well as the geometric parameters (type of reactor configuration and the number/position of the transducers) so as to maximize the process intensification benefits. The key areas for future work so as to transform the successful technique at laboratory/pilot scale into commercial technology have also been discussed. Overall, it has been established that there is immense potential for sonochemical reactors for process intensification leading to greener processing and economic benefits. Combined efforts from a wide range of disciplines such as material science, physics, chemistry and chemical engineers are required to harness the benefits at commercial scale operation. PMID:27573503

  17. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.

    1960-09-27

    A unit assembly is described for a neutronic reactor comprising a tube and plurality of spaced parallel sandwiches in the tube extending lengthwise thereof, each sandwich including a middle plate having a central opening for plutonium and other openings for fertile material at opposite ends of the plate.

  18. NEUTRONIC REACTOR

    DOEpatents

    Creutz, E.C.; Ohlinger, L.A.; Weinberg, A.M.; Wigner, E.P.; Young, G.J.

    1959-10-27

    BS>A reactor cooled by water, biphenyl, helium, or other fluid with provision made for replacing the fuel rods with the highest plutonium and fission product content without disassembling the entire core and for promptly cooling the rods after their replacement in order to prevent build-up of heat from fission product activity is described.

  19. Neutronic reactor

    DOEpatents

    Carleton, John T.

    1977-01-25

    A graphite-moderated nuclear reactor includes channels between blocks of graphite and also includes spacer blocks between adjacent channeled blocks with an axis of extension normal to that of the axis of elongation of the channeled blocks to minimize changes in the physical properties of the graphite as a result of prolonged neutron bombardment.

  20. Solid State Reactor Final Report

    SciTech Connect

    Mays, G.T.

    2004-03-10

    The Solid State Reactor (SSR) is an advanced reactor concept designed to take advantage of Oak Ridge National Laboratory's (ORNL's) recently developed graphite foam that has enhanced heat transfer characteristics and excellent high-temperature mechanical properties, to provide an inherently safe, self-regulated, source of heat for power and other potential applications. This work was funded by the U.S. Department of Energy's Nuclear Energy Research Initiative (NERI) program (Project No. 99-064) from August 1999 through September 30, 2002. The initial concept of utilizing the graphite foam as a basis for developing an advanced reactor concept envisioned that a suite of reactor configurations and power levels could be developed for several different applications. The initial focus was looking at the reactor as a heat source that was scalable, independent of any heat removal/power conversion process. These applications might include conventional power generation, isotope production and destruction (actinides), and hydrogen production. Having conducted the initial research on the graphite foam and having performed the scoping parametric analyses from neutronics and thermal-hydraulic perspectives, it was necessary to focus on a particular application that would (1) demonstrate the viability of the overall concept and (2) require a reasonably structured design analysis process that would synthesize those important parameters that influence the concept the most as part of a feasible, working reactor system. Thus, the application targeted for this concept was supplying power for remote/harsh environments and a design that was easily deployable, simplistic from an operational standpoint, and utilized the new graphite foam. Specifically, a 500-kW(t) reactor concept was pursued that is naturally load following, inherently safe, optimized via neutronic studies to achieve near-zero reactivity change with burnup, and proliferation resistant. These four major areas of research

  1. A fast spectrum dual path flow cermet reactor

    SciTech Connect

    Anghaie, S.; Feller, G.J. ); Peery, S.D.; Parsley, R.C. )

    1993-01-15

    A cermet fueled, dual path fast reactor for space nuclear propulsion applications is conceptually designed. The reactor utilizes an outer annulus core and an inner cylindrical core with radial and axial reflector. The dual path flow minimizes the impact of power peaking near the radial reflector. Basic neutronics and core design aspects of the reactor are discussed. The dual path reactor is integrated into a 25000 lbf thrust nuclear rocket.

  2. Experimental development of power reactor advanced controllers

    SciTech Connect

    Edwards, R.M.; Weng, C.K.; Lindsay, R.W.

    1992-06-01

    A systematic approach for developing and verifying advanced controllers with potential application to commercial nuclear power plants is suggested. The central idea is to experimentally demonstrate an advanced control concept first on an ultra safe research reactor followed by demonstration on a passively safe experimental power reactor and then finally adopt the technique for improving safety, performance, reliability and operability at commercial facilities. Prior to completing an experimental sequence, the benefits and utility of candidate advanced controllers should be established through theoretical development and simulation testing. The applicability of a robust optimal observer-based state feedback controller design process for improving reactor temperature response for a TRIGA research reactor, Liquid Metal-cooled Reactor (LMR), and a commercial Pressurized Water Reactor (PWR) is presented to illustrate the potential of the proposed experimental development concept.

  3. Experimental development of power reactor advanced controllers

    SciTech Connect

    Edwards, R.M. . Dept. of Nuclear Engineering); Weng, C.K. . Dept. of Mechanical Engineering); Lindsay, R.W. )

    1992-01-01

    A systematic approach for developing and verifying advanced controllers with potential application to commercial nuclear power plants is suggested. The central idea is to experimentally demonstrate an advanced control concept first on an ultra safe research reactor followed by demonstration on a passively safe experimental power reactor and then finally adopt the technique for improving safety, performance, reliability and operability at commercial facilities. Prior to completing an experimental sequence, the benefits and utility of candidate advanced controllers should be established through theoretical development and simulation testing. The applicability of a robust optimal observer-based state feedback controller design process for improving reactor temperature response for a TRIGA research reactor, Liquid Metal-cooled Reactor (LMR), and a commercial Pressurized Water Reactor (PWR) is presented to illustrate the potential of the proposed experimental development concept.

  4. Horizontal baffle for nuclear reactors

    DOEpatents

    Rylatt, John A.

    1978-01-01

    A horizontal baffle disposed in the annulus defined between the core barrel and the thermal liner of a nuclear reactor thereby physically separating the outlet region of the core from the annular area below the horizontal baffle. The horizontal baffle prevents hot coolant that has passed through the reactor core from thermally damaging apparatus located in the annulus below the horizontal baffle by utilizing the thermally induced bowing of the horizontal baffle to enhance sealing while accommodating lateral motion of the baffle base plate.

  5. NEUTRONIC REACTOR

    DOEpatents

    Wade, E.J.

    1958-09-16

    This patent relates to a reflector means for a neutronic reactor. A reflector comprised of a plurality of vertically movable beryllium control members is provided surrounding the sides of the reactor core. An absorber of fast neutrons comprised of natural uramum surrounds the reflector. An absorber of slow neutrons surrounds the absorber of fast neutrons and is formed of a plurality of beryllium blocks having natural uranium members distributcd therethrough. in addition, a movable body is positioned directly below the core and is comprised of a beryllium reflector and an absorbing member attached to the botiom thereof, the absorbing member containing a substance selected from the goup consisting of natural urantum and Th/sup 232/.

  6. REACTOR MONITORING

    DOEpatents

    Bugbee, S.J.; Hanson, V.F.; Babcock, D.F.

    1959-02-01

    A neutron density inonitoring means for reactors is described. According to this invention a tunnel is provided beneath and spaced from the active portion of the reactor and extends beyond the opposite faces of the activc portion. Neutron beam holes are provided between the active portion and the tunnel and open into the tunnel near the middle thereof. A carriage operates back and forth in the tunnel and is adapted to convey a neutron detector, such as an ion chamber, and position it beneath one of the neutron beam holes. This arrangement affords convenient access of neutron density measuring instruments to a location wherein direct measurement of neutron density within the piles can be made and at the same time affords ample protection to operating personnel.

  7. REACTOR UNLOADING

    DOEpatents

    Leverett, M.C.

    1958-02-18

    This patent is related to gas cooled reactors wherein the fuel elements are disposed in vertical channels extending through the reactor core, the cooling gas passing through the channels from the bottom to the top of the core. The invention is a means for unloading the fuel elements from the core and comprises dump values in the form of flat cars mounted on wheels at the bottom of the core structure which support vertical stacks of fuel elements. When the flat cars are moved, either manually or automatically, for normal unloading purposes, or due to a rapid rise in the reproduction ratio within the core, the fuel elements are permtted to fall by gravity out of the core structure thereby reducing the reproduction ratio or stopping the reaction as desired.

  8. Nuclear reactor

    DOEpatents

    Wade, Elman E.

    1979-01-01

    A nuclear reactor including two rotatable plugs and a positive top core holddown structure. The top core holddown structure is divided into two parts: a small core cover, and a large core cover. The small core cover, and the upper internals associated therewith, are attached to the small rotating plug, and the large core cover, with its associated upper internals, is attached to the large rotating plug. By so splitting the core holddown structures, under-the-plug refueling is accomplished without the necessity of enlarging the reactor pressure vessel to provide a storage space for the core holddown structure during refueling. Additionally, the small and large rotating plugs, and their associated core covers, are arranged such that the separation of the two core covers to permit rotation is accomplished without the installation of complex lifting mechanisms.

  9. NUCLEAR REACTOR

    DOEpatents

    Treshow, M.

    1958-08-19

    A neuclear reactor is described of the heterogeneous type and employing replaceable tubular fuel elements and heavy water as a coolant and moderator. A pluraltty of fuel tubesa having their axes parallel, extend through a tank type pressure vessel which contatns the liquid moderator. The fuel elements are disposed within the fuel tubes in the reaetive portion of the pressure vessel during normal operation and the fuel tubes have removable plug members at each end to permit charging and discharging of the fuel elements. The fuel elements are cylindrical strands of jacketed fissionable material having helical exterior ribs. A bundle of fuel elements are held within each fuel tube with their longitudinal axes parallel, the ribs serving to space them apart along their lengths. Coolant liquid is circulated through the fuel tubes between the spaced fuel elements. Suitable control rod and monitoring means are provided for controlling the reactor.

  10. NUCLEAR REACTOR

    DOEpatents

    Grebe, J.J.

    1959-12-15

    A reactor which is particularly adapted tu serve as a heat source for a nuclear powered alrcraft or rocket is described. The core of this reactor consists of a porous refractory modera;or body which is impregnated with fissionable nuclei. The core is designed so that its surface forms tapered inlet and outlet ducts which are separated by the porous moderator body. In operation a gaseous working fluid is circulated through the inlet ducts to the surface of the moderator, enters and passes through the porous body, and is heated therein. The hot gas emerges into the outlet ducts and is available to provide thrust. The principle advantage is that tremendous quantities of gas can be quickly heated without suffering an excessive pressure drop.

  11. NUCLEAR REACTORS

    DOEpatents

    Koch, L.J.; Rice, R.E. Jr.; Denst, A.A.; Rogers, A.J.; Novick, M.

    1961-12-01

    An active portion assembly for a fast neutron reactor is described wherein physical distortions resulting in adverse changes in the volume-to-mass ratio are minimized. A radially expandable locking device is disposed within a cylindrical tube within each fuel subassembly within the active portion assembly, and clamping devices expandable toward the center of the active portion assembly are disposed around the periphery thereof. (AEC)

  12. NUCLEAR REACTORS

    DOEpatents

    Long, E.; Ashby, J.W.

    1958-09-16

    ABS>A graphite moderator structure is presented for a nuclear reactor compriscd of an assembly of similarly orientated prismatic graphite blocks arranged on spaced longitudinal axes lying in common planes wherein the planes of the walls of the blocks are positioned so as to be twisted reintive to the planes of said axes so thatthe unlmpeded dtrect paths in direction wholly across the walls of the blocks are limited to the width of the blocks plus spacing between the blocks.

  13. NUCLEAR REACTOR

    DOEpatents

    Grebe, J.J.

    1961-01-24

    A core structure for neutronic reactors adapted for the propulsion of aircraft and rockets is offered. The core is designed for cooling by gaseous media, and comprises a plurality of hollow tapered tubular segments of a porous moderating material impregniated with fissionable fuel nested about a common axis. Alternate ends of the segments are joined. In operation a coolant gas passes through the porous structure and is heated.

  14. Complete genome sequence of Peptoniphilus sp. strain ING2-D1G isolated from a mesophilic lab-scale completely stirred tank reactor utilizing maize silage in co-digestion with pig and cattle manure for biomethanation.

    PubMed

    Tomazetto, Geizecler; Hahnke, Sarah; Maus, Irena; Wibberg, Daniel; Pühler, Alfred; Schlüter, Andreas; Klocke, Michael

    2014-12-20

    The bacterium Peptoniphilus sp. strain ING2-D1G (DSM 28672), a mesophilic and obligate anaerobic bacterium belonging to the order Clostridiales was isolated from a biogas-producing lab-scale completely stirred tank reactor (CSTR) optimized for anaerobic digestion of maize silage in co-fermentation with pig and cattle manure. In this study, the whole genome sequence of Peptoniphilus sp. strain ING2-D1G, a new isolate potentially involved in protein breakdown and acidogenesis during biomass degradation, is reported. The chromosome of this strain is 1.6Mb in size and encodes genes predicted to be involved in the production of acetate, lactate and butyrate specifying the acidogenic metabolism of the isolate. PMID:25242663

  15. UCLA program in reactor studies: The ARIES tokamak reactor study

    SciTech Connect

    Not Available

    1991-01-01

    The ARIES research program is a multi-institutional effort to develop several visions of tokamak reactors with enhanced economic, safety, and environmental features. The aims are to determine the potential economics, safety, and environmental features of a range of possible tokamak reactors, and to identify physics and technology areas with the highest leverage for achieving the best tokamak reactor. Four ARIES visions are currently planned for the ARIES program. The ARIES-1 design is a DT-burning reactor based on modest'' extrapolations from the present tokamak physics database and relies on either existing technology or technology for which trends are already in place, often in programs outside fusion. ARIES-2 and ARIES-4 are DT-burning reactors which will employ potential advances in physics. The ARIES-2 and ARIES-4 designs employ the same plasma core but have two distinct fusion power core designs; ARIES-2 utilize the lithium as the coolant and breeder and vanadium alloys as the structural material while ARIES-4 utilizes helium is the coolant, solid tritium breeders, and SiC composite as the structural material. Lastly, the ARIES-3 is a conceptual D-{sup 3}He reactor. During the period Dec. 1, 1990 to Nov. 31, 1991, most of the ARIES activity has been directed toward completing the technical work for the ARIES-3 design and documenting the results and findings. We have also completed the documentation for the ARIES-1 design and presented the results in various meetings and conferences. During the last quarter, we have initiated the scoping phase for ARIES-2 and ARIES-4 designs.

  16. Nuclear reactor

    DOEpatents

    Pennell, William E.; Rowan, William J.

    1977-01-01

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

  17. Nuclear Reactors. Revised.

    ERIC Educational Resources Information Center

    Hogerton, John F.

    This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Among the topics discussed are: How Reactors Work; Reactor Design; Research, Teaching, and Materials Testing; Reactors (Research, Teaching and Materials); Production Reactors; Reactors for Electric Power…

  18. NUCLEAR REACTORS

    DOEpatents

    Long, E.; Ashley, J.W.

    1958-12-16

    A graphite moderator structure is described for a gas-cooled nuclear reactor having a vertical orlentation wherein the structure is physically stable with regard to dlmensional changes due to Wigner growth properties of the graphite, and leakage of coolant gas along spaces in the structure is reduced. The structure is comprised of stacks of unlform right prismatic graphite blocks positioned in layers extending in the direction of the lengths of the blocks, the adjacent end faces of the blocks being separated by pairs of tiles. The blocks and tiles have central bores which are in alignment when assembled and are provided with cooperatlng keys and keyways for physical stability.

  19. REACTOR COMPONETN

    DOEpatents

    Creutz, E.C.

    1959-10-27

    A reactor fuel element comprised of a slug of fissionable material disposed in a sheath of corrosion resistantmaterial is described. The sheath is in the form of a tubular container closed at one end and is in tight-fitting engagement with the peripheral sunface of the slug. An inner cap is insented into the open end of the sheath against the slug, which end is then bent around the inner cap and welded thereto. An outer cap is then welded around its peripheny to the bent portion of the container.

  20. Spanish nuclear utilities: Passing the peseta

    SciTech Connect

    1995-01-01

    Financial and technical data on nuclear utilities in Spain is presented within the framework of the overall national energy policy. Technical data are of a broad nature; cancelled nuclear power plants and reactor types and locations are noted. Legal and political issues affecting nuclear utilities, including the Electrical Law, are described. The Electric Law emphasizes greater use of gas-fired power generation and increased electricity output.

  1. Simplifying microbial electrosynthesis reactor design

    PubMed Central

    Giddings, Cloelle G. S.; Nevin, Kelly P.; Woodward, Trevor; Lovley, Derek R.; Butler, Caitlyn S.

    2015-01-01

    Microbial electrosynthesis, an artificial form of photosynthesis, can efficiently convert carbon dioxide into organic commodities; however, this process has only previously been demonstrated in reactors that have features likely to be a barrier to scale-up. Therefore, the possibility of simplifying reactor design by both eliminating potentiostatic control of the cathode and removing the membrane separating the anode and cathode was investigated with biofilms of Sporomusa ovata. S. ovata reduces carbon dioxide to acetate and acts as the microbial catalyst for plain graphite stick cathodes as the electron donor. In traditional ‘H-cell’ reactors, where the anode and cathode chambers were separated with a proton-selective membrane, the rates and columbic efficiencies of microbial electrosynthesis remained high when electron delivery at the cathode was powered with a direct current power source rather than with a potentiostat-poised cathode utilized in previous studies. A membrane-less reactor with a direct-current power source with the cathode and anode positioned to avoid oxygen exposure at the cathode, retained high rates of acetate production as well as high columbic and energetic efficiencies. The finding that microbial electrosynthesis is feasible without a membrane separating the anode from the cathode, coupled with a direct current power source supplying the energy for electron delivery, is expected to greatly simplify future reactor design and lower construction costs. PMID:26029199

  2. Simplifying microbial electrosynthesis reactor design.

    PubMed

    Giddings, Cloelle G S; Nevin, Kelly P; Woodward, Trevor; Lovley, Derek R; Butler, Caitlyn S

    2015-01-01

    Microbial electrosynthesis, an artificial form of photosynthesis, can efficiently convert carbon dioxide into organic commodities; however, this process has only previously been demonstrated in reactors that have features likely to be a barrier to scale-up. Therefore, the possibility of simplifying reactor design by both eliminating potentiostatic control of the cathode and removing the membrane separating the anode and cathode was investigated with biofilms of Sporomusa ovata. S. ovata reduces carbon dioxide to acetate and acts as the microbial catalyst for plain graphite stick cathodes as the electron donor. In traditional 'H-cell' reactors, where the anode and cathode chambers were separated with a proton-selective membrane, the rates and columbic efficiencies of microbial electrosynthesis remained high when electron delivery at the cathode was powered with a direct current power source rather than with a potentiostat-poised cathode utilized in previous studies. A membrane-less reactor with a direct-current power source with the cathode and anode positioned to avoid oxygen exposure at the cathode, retained high rates of acetate production as well as high columbic and energetic efficiencies. The finding that microbial electrosynthesis is feasible without a membrane separating the anode from the cathode, coupled with a direct current power source supplying the energy for electron delivery, is expected to greatly simplify future reactor design and lower construction costs. PMID:26029199

  3. Hybrid adsorptive membrane reactor

    DOEpatents

    Tsotsis, Theodore T.; Sahimi, Muhammad; Fayyaz-Najafi, Babak; Harale, Aadesh; Park, Byoung-Gi; Liu, Paul K. T.

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  4. Hybrid adsorptive membrane reactor

    NASA Technical Reports Server (NTRS)

    Tsotsis, Theodore T. (Inventor); Sahimi, Muhammad (Inventor); Fayyaz-Najafi, Babak (Inventor); Harale, Aadesh (Inventor); Park, Byoung-Gi (Inventor); Liu, Paul K. T. (Inventor)

    2011-01-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  5. Control Means for Reactor

    DOEpatents

    Manley, J. H.

    1961-06-27

    An apparatus for controlling a nuclear reactor includes a tank just below the reactor, tubes extending from the tank into the reactor, and a thermally expansible liquid neutron absorbent material in the tank. The liquid in the tank is exposed to a beam of neutrons from the reactor which heats the liquid causing it to expand into the reactor when the neutron flux in the reactor rises above a predetermincd danger point. Boron triamine may be used for this purpose.

  6. NEUTRONIC REACTOR

    DOEpatents

    Daniels, F.

    1962-12-18

    A power plant is described comprising a turbine and employing round cylindrical fuel rods formed of BeO and UO/sub 2/ and stacks of hexagonal moderator blocks of BeO provided with passages that loosely receive the fuel rods so that coolant may flow through the passages over the fuels to remove heat. The coolant may be helium or steam and fiows through at least one more heat exchanger for producing vapor from a body of fluid separate from the coolant, which fluid is to drive the turbine for generating electricity. By this arrangement the turbine and directly associated parts are free of particles and radiations emanating from the reactor. (AEC)

  7. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.

    1957-09-17

    A reactor of the type having coolant liquid circulated through clad fuel elements geometrically arranged in a solid moderator, such as graphite, is described. The core is enclosed in a pressure vessel and suitable shielding, wherein means is provided for circulating vapor through the core to superheat the same. This is accomplished by drawing off the liquid which has been heated in the core due to the fission of the fuel, passing it to a nozzle within a chamber where it flashes into a vapor, and then passing the vapor through separate tubes extending through the moderator to pick up more heat developed in the core due to the fission of the fuel, thereby producing superheated vapor.

  8. NEUTRONIC REACTOR

    DOEpatents

    Stewart, H.B.

    1958-12-23

    A nuclear reactor of the type speclfically designed for the irradiation of materials is discussed. In this design a central cyllndrical core of moderating material ls surrounded by an active portlon comprlsed of an annular tank contalning fissionable material immersed ln a liquid moderator. The active portion ls ln turn surrounded by a reflector, and a well ls provided in the center of the core to accommodate the materlals to be irradiated. The over-all dimensions of the core ln at least one plane are equal to or greater than twice the effective slowing down length and equal to or less than twlce the effective diffuslon length for neutrons in the core materials.

  9. Nuclear reactor

    DOEpatents

    Yant, Howard W.; Stinebiser, Karl W.; Anzur, Gregory C.

    1977-01-01

    A nuclear reactor, particularly a liquid-metal breeder reactor, whose upper internals include outlet modules for channeling the liquid-metal coolant from selected areas of the outlet of the core vertically to the outlet plenum. The modules are composed of a highly-refractory, high corrosion-resistant alloy, for example, INCONEL-718. Each module is disposed to confine and channel generally vertically the coolant emitted from a subplurality of core-component assemblies. Each module has a grid with openings, each opening disposed to receive the coolant from an assembly of the subplurality. The grid in addition serves as a holdown for the assemblies of the corresponding subplurality preventing their excessive ejection upwardly from the core. In the region directly over the core the outlet modules are of such peripheral form that they nest forming a continuum over the core-component assemblies whose outlet coolant they confine. Each subassembly includes a chimney which confines the coolant emitted by its corresponding subassemblies to generally vertical flow between the outlet of the core and the outlet plenum. Each subplurality of assemblies whose emitted coolant is confined by an outlet module includes assemblies which emit lower-temperature coolant, for example, a control-rod assembly, or fertile assemblies, and assemblies which emit coolant of substantially higher temperature, for example, fuel-rod assemblies. The coolants of different temperatures are mixed in the chimneys reducing the effect of stripping (hot-cold temperature fluctuations) on the remainder of the upper internals which are composed typically of AISI-304 or AISI-316 stainless steel.

  10. NUCLEAR REACTOR FUEL ELEMENT

    DOEpatents

    Wheelock, C.W.; Baumeister, E.B.

    1961-09-01

    A reactor fuel element utilizing fissionable fuel materials in plate form is described. This fuel element consists of bundles of fuel-bearing plates. The bundles are stacked inside of a tube which forms the shell of the fuel element. The plates each have longitudinal fins running parallel to the direction of coolant flow, and interspersed among and parallel to the fins are ribs which position the plates relative to each other and to the fuel element shell. The plate bundles are held together by thin bands or wires. The ex tended surface increases the heat transfer capabilities of a fuel element by a factor of 3 or more over those of a simple flat plate.

  11. FLUID MODERATED REACTOR

    DOEpatents

    Wigner, E.P.; Ohlinger, L.A.; Young, G.J.; Weinberg, A.M.

    1957-10-22

    A reactor which utilizes fissionable fuel elements in rod form immersed in a moderator or heavy water and a means of circulating the heavy water so that it may also function as a coolant to remove the heat generated by the fission of the fuel are described. In this design, the clad fuel elements are held in vertical tubes immersed in heavy water in a tank. The water is circulated in a closed system by entering near the tops of the tubes, passing downward through the tubes over the fuel elements and out into the tank, where it is drawn off at the bottom, passed through heat exchangers to give up its heat and then returned to the tops of the tubes for recirculation.

  12. Reactor and method of operation

    DOEpatents

    Wheeler, John A.

    1976-08-10

    A nuclear reactor having a flattened reactor activity curve across the reactor includes fuel extending over a lesser portion of the fuel channels in the central portion of the reactor than in the remainder of the reactor.

  13. Power ascension strategy following a reactor trip during EOC coastdown

    SciTech Connect

    Beard, C.L.; Heibel, M.D. ); Lesnick, D.C. )

    1992-01-01

    The difficulties associated with returning a reactor to the pretrip power level following a reactor trip during an end-of-cycle (EOC) power coastdown maneuver, and maintaining it once achieved, have caused utilities to abandon the restart and enter their refueling outages ahead of schedule. The Commonwealth Edison Company (CECo) Braidwood and Byron units have experienced reactor trips during EOC power coastdown maneuvers and have successfully performed restarts. The installation of the BEACON core monitoring system, which provides core monitoring, measurement reduction, core analysis and follow, and core prediction capability utilizing a very fast and accurate three-dimensional nodal code, at the CECo Byron, Braidwood, and Zion stations allows the reactor engineers at these units to accurately determine reactor response. The capabilities of the BEACON system allow an optimal return to power strategy to be developed and continuously updated. This paper presents a method for establishing the optimal return to power strategy utilizing the BEACON system.

  14. Mechanical cutting of irradiated reactor internal components

    SciTech Connect

    Anderson, Michael G.

    2008-01-15

    Mechanical cutting methods to volume reduce and package reactor internal components are now a viable solution for stakeholders challenged with the retirement of first generation nuclear facilities. The recent completion of the removal of the Reactor Vessel Internals (RVI) from within the Sacramento Municipal Utility District's (SMUD) Rancho Seco Nuclear Power Plant demonstrates that unlike previous methods, inclusive of plasma arc and abrasive water-jet cutting, mechanical cutting minimizes exposure to workers, costly water cleanup, and excessive secondary waste generation. Reactor internal components were segmented, packaged, and removed from the reactor building for shipment or storage, allowing the reactor cavity to be drained and follow-on reactor segmentation activities to proceed in the dry state. Area exposure rates at the work positions during the segmentation process were generally 1 mR per hr. Radiological exposure documented for the underwater segmentation processes totaled 13 person rem. The reactor internals weighing 343,000 pounds were segmented into over 200 pieces for maximum shipping package efficiency and produced 5,600 lb of stainless steel chips and shavings which were packaged in void spaces of existing disposal containers, therefore creating no additional disposal volume. Because no secondary waste was driven into suspension in the reactor cavity water, the water was free released after one pass through a charcoal bed and ion exchange filter system. Mechanical cutting techniques are capable of underwater segmentation of highly radioactive components on a large scale. This method minimized radiological exposure and costly water cleanup while creating no secondary waste.

  15. Control console replacement at the WPI Reactor

    SciTech Connect

    Not Available

    1992-01-01

    With partial funding from the Department of Energy (DOE) University Reactor Instrumentation Upgrade Program (DOE Grant No. DE-FG02-90ER12982), the original control console at the Worcester Polytechnic Institute (WPI) Reactor has been replaced with a modern system. The new console maintains the original design bases and functionality while utilizing current technology. An advanced remote monitoring system has been added to augment the educational capabilities of the reactor. Designed and built by General Electric in 1959, the open pool nuclear training reactor at WPI was one of the first such facilities in the nation located on a university campus. Devoted to undergraduate use, the reactor and its related facilities have been since used to train two generations of nuclear engineers and scientists for the nuclear industry. The reactor power level was upgraded from 1 to 10 kill in 1969, and its operating license was renewed for 20 years in 1983. In 1988, the reactor was converted to low enriched uranium. The low power output of the reactor and ergonomic facility design make it an ideal tool for undergraduate nuclear engineering education and other training.

  16. Reactor safety method

    DOEpatents

    Vachon, Lawrence J.

    1980-03-11

    This invention relates to safety means for preventing a gas cooled nuclear reactor from attaining criticality prior to start up in the event the reactor core is immersed in hydrogenous liquid. This is accomplished by coating the inside surface of the reactor coolant channels with a neutral absorbing material that will vaporize at the reactor's operating temperature.

  17. NEUTRONIC REACTOR MANIPULATING DEVICE

    DOEpatents

    Ohlinger, L.A.

    1962-08-01

    A cable connecting a control rod in a reactor with a motor outside the reactor for moving the rod, and a helical conduit in the reactor wall, through which the cable passes are described. The helical shape of the conduit prevents the escape of certain harmful radiations from the reactor. (AEC)

  18. Nuclear reactor

    DOEpatents

    Thomson, Wallace B.

    2004-03-16

    A nuclear reactor comprising a cylindrical pressure vessel, an elongated annular core centrally disposed within and spaced from the pressure vessel, and a plurality of ducts disposed longitudinally of the pressure vessel about the periphery thereof, said core comprising an annular active portion, an annular reflector just inside the active portion, and an annular reflector just outside the active a portion, said annular active portion comprising rectangular slab, porous fuel elements radially disposed around the inner reflector and extending the length of the active portion, wedge-shaped, porous moderator elements disposed adjacent one face of each fuel element and extending the length of the fuel element, the fuel and moderator elements being oriented so that the fuel elements face each other and the moderator elements do likewise, adjacent moderator elements being spaced to provide air inlet channels, and adjacent fuel elements being spaced to provide air outlet channels which communicate with the interior of the peripheral ducts, and means for introducing air into the air inlet channels which passes through the porous moderator elements and porous fuel elements to the outlet channel.

  19. YEAR 2 BIOMASS UTILIZATION

    SciTech Connect

    Christopher J. Zygarlicke

    2004-11-01

    This Energy & Environmental Research Center (EERC) Year 2 Biomass Utilization Final Technical Report summarizes multiple projects in biopower or bioenergy, transportation biofuels, and bioproducts. A prototype of a novel advanced power system, termed the high-temperature air furnace (HITAF), was tested for performance while converting biomass and coal blends to energy. Three biomass fuels--wood residue or hog fuel, corn stover, and switchgrass--and Wyoming subbituminous coal were acquired for combustion tests in the 3-million-Btu/hr system. Blend levels were 20% biomass--80% coal on a heat basis. Hog fuel was prepared for the upcoming combustion test by air-drying and processing through a hammer mill and screen. A K-Tron biomass feeder capable of operating in both gravimetric and volumetric modes was selected as the HITAF feed system. Two oxide dispersion-strengthened (ODS) alloys that would be used in the HITAF high-temperature heat exchanger were tested for slag corrosion rates. An alumina layer formed on one particular alloy, which was more corrosion-resistant than a chromia layer that formed on the other alloy. Research activities were completed in the development of an atmospheric pressure, fluidized-bed pyrolysis-type system called the controlled spontaneous reactor (CSR), which is used to process and condition biomass. Tree trimmings were physically and chemically altered by the CSR process, resulting in a fuel that was very suitable for feeding into a coal combustion or gasification system with little or no feed system modifications required. Experimental procedures were successful for producing hydrogen from biomass using the bacteria Thermotoga, a deep-ocean thermal vent organism. Analytical procedures for hydrogen were evaluated, a gas chromatography (GC) method was derived for measuring hydrogen yields, and adaptation culturing and protocols for mutagenesis were initiated to better develop strains that can use biomass cellulose. Fly ash derived from

  20. An Idealized Direct-Contact Biomass Pyrolysis Reactor Model

    NASA Technical Reports Server (NTRS)

    Miller, R. S.; Bellan, J.

    1996-01-01

    A numerical study is performed in order to assess the performance of biomass pyrolysis reactors which utilize direct particle-wall thermal conduction heating. An idealized reactor configuration consisting of a flat-plate turbulent boundary layer flow with particle convection along the heated wall and incorporating particle re-entrainment is considered.

  1. POTENTIAL BENCHMARKS FOR ACTINIDE PRODUCTION IN HANFORD REACTORS

    SciTech Connect

    PUIGH RJ; TOFFER H

    2011-10-19

    A significant experimental program was conducted in the early Hanford reactors to understand the reactor production of actinides. These experiments were conducted with sufficient rigor, in some cases, to provide useful information that can be utilized today in development of benchmark experiments that may be used for the validation of present computer codes for the production of these actinides in low enriched uranium fuel.

  2. Improved methodology for temperature predictions in advanced reactors

    SciTech Connect

    Ambrosek, R.G.; Chang, G.S.

    1995-10-01

    Advanced nuclear reactors maximize power and/or flux levels for increased performance levels. One of the challenges is accurate prediction of temperatures in the structural components and experiments. An improved methodology utilizing the computer codes MCNP and ABAQUS has been demonstrated in instrumented experiments at the Advanced Test Reactor. The analytical predictions have shown excellent agreement with the measured results.

  3. Packed bed reactor for photochemical .sup.196 Hg isotope separation

    DOEpatents

    Grossman, Mark W.; Speer, Richard

    1992-01-01

    Straight tubes and randomly oriented pieces of tubing having been employed in a photochemical mercury enrichment reactor and have been found to improve the enrichment factor (E) and utilization (U) compared to a non-packed reactor. One preferred embodiment of this system uses a moving bed (via gravity) for random packing.

  4. Challenges in the Development of High Temperature Reactors

    SciTech Connect

    Piyush Sabharwall; Shannon M. Bragg-Sitton; Carl Stoots

    2013-10-01

    Advanced reactor designs offer potentially significant improvements over currently operating light water reactors including improved fuel utilization, increased efficiency, higher temperature operation (enabling a new suite of non-electric industrial process heat applications), and increased safety. As with most technologies, these potential performance improvements come with a variety of challenges to bringing advanced designs to the marketplace. There are technical challenges in material selection and thermal hydraulic and power conversion design that arise particularly for higher temperature, long life operation (possibly >60 years). The process of licensing a new reactor design is also daunting, requiring significant data collection for model verification and validation to provide confidence in safety margins associated with operating a new reactor design under normal and off-normal conditions. This paper focuses on the key technical challenges associated with two proposed advanced reactor concepts: the helium gas cooled Very High Temperature Reactor (VHTR) and the molten salt cooled Advanced High Temperature Reactor (AHTR).

  5. Testing of Gas Reactor Materials and Fuel in the Advanced Test Reactor

    SciTech Connect

    S. Blaine Grover

    2004-10-01

    The Advanced Test Reactor (ATR) has long been involved in testing gas reactor materials, and has developed facilities well suited for providing the right conditions and environment for gas reactor tests. This paper discusses the different types of irradiation hardware that have been utilized in past ATR irradiation tests of gas reactor materials. The new Gas Test Loop facility currently being developed for the ATR is discussed and the different approaches being considered in the design of the facility. The different options for an irradiation experiment such as active versus passive temperature control, neutron spectrum tailoring, and different types of lead experiment sweep gas monitors are also discussed. The paper is then concluded with examples of different past and present gas reactor material and fuel irradiations.

  6. TESTING OF GAS REACTOR MATERIALS AND FUEL IN THE ADVANCED TEST REACTOR

    SciTech Connect

    Grover, S.B.

    2004-10-06

    The Advanced Test Reactor (ATR) has long been involved in testing gas reactor materials, and has developed facilities well suited for providing the right conditions and environment for gas reactor tests. This paper discusses the different types of irradiation hardware that have been utilized in past ATR irradiation tests of gas reactor materials. The new Gas Test Loop facility currently being developed for the ATR is discussed and the different approaches being considered in the design of the facility. The different options for an irradiation experiment such as active versus passive temperature control, neutron spectrum tailoring, and different types of lead experiment sweep gas monitors are also discussed. The paper is then concluded with examples of different past and present gas reactor material and fuel irradiations.

  7. Design of a 25-kWe Surface Reactor System Based on SNAP Reactor Technologies

    NASA Astrophysics Data System (ADS)

    Dixon, David D.; Hiatt, Matthew T.; Poston, David I.; Kapernick, Richard J.

    2006-01-01

    A Hastelloy-X clad, sodium-potassium (NaK-78) cooled, moderated spectrum reactor using uranium zirconium hydride (UZrH) fuel based on the SNAP program reactors is a promising design for use in surface power systems. This paper presents a 98 kWth reactor for a power system the uses multiple Stirling engines to produce 25 kWe-net for 5 years. The design utilizes a pin type geometry containing UZrHx fuel clad with Hastelloy-X and NaK-78 flowing around the pins as coolant. A compelling feature of this design is its use of 49.9% enriched U, allowing it to be classified as a category III-D attractiveness and reducing facility costs relative to highly-enriched space reactor concepts. Presented below are both the design and an analysis of this reactor's criticality under various safety and operations scenarios.

  8. Design of a 25-kWe Surface Reactor System Based on SNAP Reactor Technologies

    SciTech Connect

    Dixon, David D.; Hiatt, Matthew T.; Poston, David I.; Kapernick, Richard J.

    2006-01-20

    A Hastelloy-X clad, sodium-potassium (NaK-78) cooled, moderated spectrum reactor using uranium zirconium hydride (UZrH) fuel based on the SNAP program reactors is a promising design for use in surface power systems. This paper presents a 98 kWth reactor for a power system the uses multiple Stirling engines to produce 25 kWe-net for 5 years. The design utilizes a pin type geometry containing UZrHx fuel clad with Hastelloy-X and NaK-78 flowing around the pins as coolant. A compelling feature of this design is its use of 49.9% enriched U, allowing it to be classified as a category III-D attractiveness and reducing facility costs relative to highly-enriched space reactor concepts. Presented below are both the design and an analysis of this reactor's criticality under various safety and operations scenarios.

  9. Hot Gas Desulfurization Using Transport Reactors

    SciTech Connect

    Moorehead, E.L.

    1996-12-31

    Sierra Pacific Power Company is building a 100 MW, IGCC power plant based on KRW fluid bed gasifier technology that utilizes transport reactors for hot gas desulfurization and sorbent regeneration. Use of a transport absorber avoids the need for pre-filtration of dust-laden gasifier effluent, while a transport regenerator allows for the use of 100% air without the need for heat exchange equipment. Selection of transport reactors for hot gas desulfurization using a proprietary sorbent, based on testing performed in a transport reactor test unit (TRTU) at the M. W. Kellogg Technology Development Center and in a fixed bed reactor at Morgantown Energy Technology Center (METC), is outlined. The results obtained in these two test facilities and reasons for selecting transport reactors for the IGCC power plant in preference to either fixed bed or fluidized bed reactors are discussed. This paper reviews the evolution of the hot gas desulfurization system designs and includes selected results on H{sub 2}S absorption and regeneration of sulfided sorbent over several absorption/regeneration cycles conducted in the TRTU and the METC fixed bed reactor. The original design for the Sierra Pacific Project was based on fixed bed reactors with zinc ferrite as the sorbent. Owing to the high steam requirements of this sorbent, zinc titanate was selected and tested in a fixed bed reactor and was found unacceptable due to loss of strength on cyclic absorption/regeneration operation. Another sorbent evaluated was Z-Sorb{reg_sign}, a proprietary sorbent developed by Phillips Petroleum Company, was found to have excellent sulfur capacity, structural strength and regenerability. Steam was found unsuitable as fixed bed regenerator diluent, this results in a requirement for a large amount of inert gas, whereas a transport regenerator requires no diluent. The final Sierra design features transport reactors for both desulfurization and regeneration steps using neat air. 3 refs., 3 figs., 2 tabs.

  10. HEAVY WATER MODERATED NEUTRONIC REACTOR

    DOEpatents

    Szilard, L.

    1958-04-29

    A nuclear reactor of the type which utilizes uranium fuel elements and a liquid coolant is described. The fuel elements are in the form of elongated tubes and are disposed within outer tubes extending through a tank containing heavy water, which acts as a moderator. The ends of the fuel tubes are connected by inlet and discharge headers, and liquid bismuth is circulated between the headers and through the fuel tubes for cooling. Helium is circulated through the annular space between the outer tubes in the tank and the fuel tubes to cool the water moderator to prevent boiling. The fuel tubes are covered with a steel lining, and suitable control means, heat exchange means, and pumping means for the coolants are provided to complete the reactor assembly.

  11. NON-CORROSIVE REACTOR FUEL SYSTEM

    DOEpatents

    Herrick, C.C.

    1962-08-14

    A non-corrosive nuclear reactor fuel system was developed utilizing a molten plutonium-- iron alloy fuel having about 2 at.% carbon and contained in a tantalum vessel. This carbon reacts with the interior surface of the tantalum vessel to form a plutonium resistant self-healing tantalum carbide film. (AEC)

  12. Light Water Reactor Sustainability Constellation Pilot Project FY11 Summary Report

    SciTech Connect

    R. Johansen

    2011-09-01

    Summary report for Fiscal Year 2011 activities associated with the Constellation Pilot Project. The project is a joint effor between Constellation Nuclear Energy Group (CENG), EPRI, and the DOE Light Water Reactor Sustainability Program. The project utilizes two CENG reactor stations: R.E. Ginna and Nine Point Unit 1. Included in the report are activities associate with reactor internals and concrete containments.

  13. STEAM STIRRED HOMOGENEOUS NUCLEAR REACTOR

    DOEpatents

    Busey, H.M.

    1958-06-01

    A homogeneous nuclear reactor utilizing a selfcirculating liquid fuel is described. The reactor vessel is in the form of a vertically disposed tubular member having the lower end closed by the tube walls and the upper end closed by a removal fianged assembly. A spherical reaction shell is located in the lower end of the vessel and spaced from the inside walls. The reaction shell is perforated on its lower surface and is provided with a bundle of small-diameter tubes extending vertically upward from its top central portion. The reactor vessel is surrounded in the region of the reaction shell by a neutron reflector. The liquid fuel, which may be a solution of enriched uranyl sulfate in ordinary or heavy water, is mainiained at a level within the reactor vessel of approximately the top of the tubes. The heat of the reaction which is created in the critical region within the spherical reaction shell forms steam bubbles which more upwardly through the tubes. The upward movement of these bubbles results in the forcing of the liquid fuel out of the top of these tubes, from where the fuel passes downwardly in the space between the tubes and the vessel wall where it is cooled by heat exchangers. The fuel then re-enters the critical region in the reaction shell through the perforations in the bottom. The upper portion of the reactor vessel is provided with baffles to prevent the liquid fuel from splashing into this region which is also provided with a recombiner apparatus for recombining the radiolytically dissociated moderator vapor and a control means.

  14. In vivo anticancer, anti-inflammatory, and toxicity studies of mixed-ligand Cu(II) complexes of dien and its Schiff dibases with heterocyclic aldehydes and 2-amino-2-thiazoline. Crystal structure of [Cu(dien)(Br)(2a-2tzn)](Br)(H(2)O).

    PubMed

    Chaviara, A Th; Christidis, P C; Papageorgiou, A; Chrysogelou, E; Hadjipavlou-Litina, D J; Bolos, C A

    2005-11-01

    A new series of complexes of the type [Cu(dien)(2a-2tzn)Y(2)] and [Cu(dienXX)(2a-2tzn)Y(2)], where dien=diethylenetriamine and dienXX=Schiff dibase of diethylenetriamine formed with 2-furaldehyde (dienOO), 2-thiophenecarboxaldehyde (dienSS), or pyrrol-2-carboxaldehyde (dienNN); Y=Cl, Br or NO(3); and 2a-2tzn=2-amino-2-thiazoline, were synthesized and their structure established by C, H, N and Cu analysis; IR and electronic spectra; magnetic susceptibility; and molar conductivity. The isolated complexes are monomers, paramagnetic, and electrolytes of types 1:1 or 1:2. In both types of solid state complexes, [Cu(dien)(2a-2tzn)Y(2)] and [Cu(dienXX)(2a-2tzn)Y(2)], dien and its Schiff dibases are bonded to Cu(II) in a tridentate fashion through 3N atoms. The coordination sphere is completed by the endocyclic nitrogen of the thiazoline moiety and by two Cl, Br, or NO(3) groups with distorted octahedral geometry. The proposed structure of these compounds was supported by X-ray analysis of [Cu(dien)(Br)(2a-2tzn)](Br)(H(2)O). The coordination polyhedron around the copper atom can be described as a distorted square pyramid [Cu(dien)(Br)(2a-2tzn)](+). Its basal plane is occupied by the four nitrogen atoms of the dien and thiazoline ligands with Cu-N distances ranging between 1.996(6) and 2.032(3)A, and the axial position is occupied by one of the two bromine atoms (Br1) with a Cu1-Br1 bond distance of 2.782(1)A. The second bromine atom (Br2) is 4.694(2)A from the copper atom, which exists as a discrete anion and is responsible for the cationic nature of the complex. Results regarding toxicity, antitumor, and anti-inflammatory activities of the investigated compounds are promising and allow the selection of a lead compound for further biological studies. PMID:16144711

  15. EXPERIMENTAL LIQUID METAL FUEL REACTOR

    DOEpatents

    Happell, J.J.; Thomas, G.R.; Denise, R.P.; Bunts, J.L. Jr.

    1962-01-23

    A liquid metal fuel nuclear fission reactor is designed in which the fissionable material is dissolved or suspended in a liquid metal moderator and coolant. The liquid suspension flows into a chamber in which a critical amount of fissionable material is obtained. The fluid leaves the chamber and the heat of fission is extracted for power or other utilization. The improvement is in the support arrangement for a segrnented graphite core to permit dif ferential thermal expansion, effective sealing between main and blanket liquid metal flows, and avoidance of excessive stress development in the graphite segments. (AEC)

  16. Hybrid plasmachemical reactor

    SciTech Connect

    Lelevkin, V. M. Smirnova, Yu. G.; Tokarev, A. V.

    2015-04-15

    A hybrid plasmachemical reactor on the basis of a dielectric barrier discharge in a transformer is developed. The characteristics of the reactor as functions of the dielectric barrier discharge parameters are determined.

  17. Attrition reactor system

    SciTech Connect

    Scott, C.D.; Davison, B.H.

    1993-09-28

    A reactor vessel for reacting a solid particulate with a liquid reactant has a centrifugal pump in circulatory flow communication with the reactor vessel for providing particulate attrition, resulting in additional fresh surface where the reaction can occur. 2 figures.

  18. Attrition reactor system

    SciTech Connect

    Scott, Charles D.; Davison, Brian H.

    1993-01-01

    A reactor vessel for reacting a solid particulate with a liquid reactant has a centrifugal pump in circulatory flow communication with the reactor vessel for providing particulate attrition, resulting in additional fresh surface where the reaction can occur.

  19. Laboratory instrumentation modernization at the WPI Nuclear Reactor Facility

    SciTech Connect

    Not Available

    1995-01-01

    With partial funding from the Department of Energy (DOE) University Reactor Instrumentation Program several laboratory instruments utilized by students and researchers at the WPI Nuclear Reactor Facility have been upgraded or replaced. Designed and built by General Electric in 1959, the open pool nuclear training reactor at WPI was one of the first such facilities in the nation located on a university campus. Devoted to undergraduate use, the reactor and its related facilities have been since used to train two generations of nuclear engineers and scientists for the nuclear industry. The low power output of the reactor and an ergonomic facility design make it an ideal tool for undergraduate nuclear engineering education and other training. The reactor, its control system, and the associate laboratory equipment are all located in the same room. Over the years, several important milestones have taken place at the WPI reactor. In 1969, the reactor power level was upgraded from 1 kW to 10 kW. The reactor`s Nuclear Regulatory Commission operating license was renewed for 20 years in 1983. In 1988, under DOE Grant No. DE-FG07-86ER75271, the reactor was converted to low-enriched uranium fuel. In 1992, again with partial funding from DOE (Grant No. DE-FG02-90ER12982), the original control console was replaced.

  20. Role of research reactors in training of NPP personnel with special focus on training reactor VR-1

    SciTech Connect

    Sklenka, L.; Rataj, J.; Frybort, J.; Huml, O.

    2012-07-01

    Research reactors play an important role in providing key personnel of nuclear power plants a hands-on experience from operation and experiments at nuclear facilities. Training of NPP (Nuclear Power Plant) staff is usually deeply theoretical with an extensive utilisation of simulators and computer visualisation. But a direct sensing of the reactor response to various actions can only improve the personnel awareness of important aspects of reactor operation. Training Reactor VR-1 and its utilization for training of NPP operators and other professionals from Czech Republic and Slovakia is described. Typical experimental exercises and good practices in organization of a training program are demonstrated. (authors)

  1. NEUTRONIC REACTOR POWER PLANT

    DOEpatents

    Metcalf, H.E.

    1962-12-25

    This patent relates to a nuclear reactor power plant incorporating an air-cooled, beryllium oxide-moderated, pebble bed reactor. According to the invention means are provided for circulating a flow of air through tubes in the reactor to a turbine and for directing a sidestream of the circu1ating air through the pebble bed to remove fission products therefrom as well as assist in cooling the reactor. (AEC)

  2. Period meter for reactors

    DOEpatents

    Rusch, Gordon K.

    1976-01-06

    An improved log N amplifier type nuclear reactor period meter with reduced probability for noise-induced scrams is provided. With the reactor at low power levels a sampling circuit is provided to determine the reactor period by measuring the finite change in the amplitude of the log N amplifier output signal for a predetermined time period, while at high power levels, differentiation of the log N amplifier output signal provides an additional measure of the reactor period.

  3. Reactor System Transient Code.

    Energy Science and Technology Software Center (ESTSC)

    1999-07-14

    RELAP3B describes the behavior of water-cooled nuclear reactors during postulated accidents or power transients, such as large reactivity excursions, coolant losses or pump failures. The program calculates flows, mass and energy inventories, pressures, temperatures, and steam qualities along with variables associated with reactor power, reactor heat transfer, or control systems. Its versatility allows one to describe simple hydraulic systems as well as complex reactor systems.

  4. Advanced Test Reactor Tour

    ScienceCinema

    Miley, Don

    2013-05-28

    The Advanced Test Reactor at Idaho National Laboratory is the foremost nuclear materials test reactor in the world. This virtual tour describes the reactor, how experiments are conducted, and how spent nuclear fuel is handled and stored. For more information about INL research, visit http://www.facebook.com/idahonationallaboratory.

  5. NEUTRONIC REACTOR SHIELDING

    DOEpatents

    Borst, L.B.

    1961-07-11

    A special hydrogenous concrete shielding for reactors is described. In addition to Portland cement and water, the concrete essentially comprises 30 to 60% by weight barytes aggregate for enhanced attenuation of fast neutrons. The biological shields of AEC's Oak Ridge Graphite Reactor and Materials Testing Reactor are particular embodiments.

  6. Improved vortex reactor system

    DOEpatents

    Diebold, James P.; Scahill, John W.

    1995-01-01

    An improved vortex reactor system for affecting fast pyrolysis of biomass and Refuse Derived Fuel (RDF) feed materials comprising: a vortex reactor having its axis vertically disposed in relation to a jet of a horizontally disposed steam ejector that impels feed materials from a feeder and solids from a recycle loop along with a motive gas into a top part of said reactor.

  7. Advanced Test Reactor Tour

    SciTech Connect

    Miley, Don

    2011-01-01

    The Advanced Test Reactor at Idaho National Laboratory is the foremost nuclear materials test reactor in the world. This virtual tour describes the reactor, how experiments are conducted, and how spent nuclear fuel is handled and stored. For more information about INL research, visit http://www.facebook.com/idahonationallaboratory.

  8. High solids fermentation reactor

    DOEpatents

    Wyman, Charles E.; Grohmann, Karel; Himmel, Michael E.; Richard, Christopher J.

    1993-03-02

    A fermentation reactor and method for fermentation of materials having greater than about 10% solids. The reactor includes a rotatable shaft along the central axis, the shaft including rods extending outwardly to mix the materials. The reactor and method are useful for anaerobic digestion of municipal solid wastes to produce methane, for production of commodity chemicals from organic materials, and for microbial fermentation processes.

  9. High solids fermentation reactor

    DOEpatents

    Wyman, Charles E.; Grohmann, Karel; Himmel, Michael E.; Richard, Christopher J.

    1993-01-01

    A fermentation reactor and method for fermentation of materials having greater than about 10% solids. The reactor includes a rotatable shaft along the central axis, the shaft including rods extending outwardly to mix the materials. The reactor and method are useful for anaerobic digestion of municipal solid wastes to produce methane, for production of commodity chemicals from organic materials, and for microbial fermentation processes.

  10. University Reactor Instrumentation Grant

    SciTech Connect

    S. M. Bajorek

    2000-02-01

    A noble gas air monitoring system was purchased through the University Reactor Instrumentation Grant Program. This monitor was installed in the Kansas State TRIGA reactor bay at a location near the top surface of the reactor pool according to recommendation by the supplier. This system is now functional and has been incorporated into the facility license.

  11. NUCLEAR REACTOR CONTROL SYSTEM

    DOEpatents

    Epler, E.P.; Hanauer, S.H.; Oakes, L.C.

    1959-11-01

    A control system is described for a nuclear reactor using enriched uranium fuel of the type of the swimming pool and other heterogeneous nuclear reactors. Circuits are included for automatically removing and inserting the control rods during the course of normal operation. Appropriate safety circuits close down the nuclear reactor in the event of emergency.

  12. Utilizing FFTF: the keystone for breeder development

    SciTech Connect

    Ziff, J.J.; Arneson, S.O.

    1981-05-01

    This paper describes the role of the Fast Flux Test Facility (FFTF) in the US Department of Energy sponsored Liquid Metal Fast Breeder Reactor (LMFBR) Program. The programs that are in place to ensure that the FFTF fulfills its role as an essential key to the development of LMFBR technology are delineated. A detailed FFTF Operating Plan has been developed to present in integrated form the strategy for gaining maximum useful information from the planned FFTF operations. The three principal areas of FFTF Utilization: Plant Utilization, Irradiation Testing, and Safety, combine to form the overall FFTF Operating Plan. Primary areas where FFTF is already making major contributions to LMFBR development are described.

  13. Controlling Your Utility Rates.

    ERIC Educational Resources Information Center

    Lucht, Ray; Dembowski, Frederick L.

    1985-01-01

    A cost-effective alternative to high utility bills for middle-sized and smaller utility users is the service of utility rate consultants. The consultants analyze utility invoices for the previous 12 months to locate available refunds or credits. (MLF)

  14. PHISICS toolkit: Multi-reactor transmutation analysis utility - MRTAU

    SciTech Connect

    Alfonsi, A.; Rabiti, C.; Epiney, A. S.; Wang, Y.; Cogliati, J.

    2012-07-01

    The principal idea of this paper is to present the new capabilities available in the PHISICS toolkit, connected with the implementation of the depletion code MRTAU, a generic depletion/decay/burn-up code developed at the Idaho National Laboratory. It is programmed in a modular structure and modern FORTRAN 95/2003. The code tracks the time evolution of the isotopic concentration of a given material accounting for nuclear reactions happening in presence of neutron flux and also due to natural decay. MRTAU has two different methods to perform the depletion calculation, in order to let the user choose the best on with respect to his needs. Both the methodologies and some significant results are reported in this paper. (authors)

  15. PHISICS TOOLKIT: MULTI-REACTOR TRANSMUTATION ANALYSIS UTILITY - MRTAU

    SciTech Connect

    Andrea Alfonsi; Cristian Rabiti; Aaron S. Epiney; Yaqi Wang; Joshua Cogliati

    2012-04-01

    The principal idea of this paper is to present the new capabilities available in the PHISICS toolkit, connected with the implementation of the depletion code MRTAU, a generic depletion/ decay/burn-up code developed at the Idaho National Laboratory. It is programmed in a modular structure and modern FORTRAN 95/2003. The code tracks the time evolution of the isotopic concentration of a given material accounting for nuclear reaction happening in presence of neutron flux and also due to natural decay. MRTAU has two different methods to perform the depletion calculation, in order to let the user choose the best one respect his needs. Both the methodologies and some significant results are reported in this paper.

  16. Aging assessment and license renewals: Plant life management for the first stage boiling water reactor

    SciTech Connect

    Tezuka, Kenichi; Kawamura, Shinichi; Aoki, Masataka; Mori, Tsuguo

    1996-09-01

    The first stage Boiling Water Reactors (BWRs) have been operating more than 25 years. Some components have potential of failure by aging. So, evaluations have been done for the main components such as Reactor Pressure Vessel (RPV), Reactor Internals, Primary Coolant Piping, Reactor Recirculation Pump, Cable (Inside PCV), Primary Containment Vessel (PCV) and Concrete Structure. This evaluation has been done by joint study between electric utilities and manufacturers to confirm integrity and identify necessary development.

  17. Crystal structures of hydrates of simple inorganic salts. II. Water-rich calcium bromide and iodide hydrates: CaBr2 · 9H2O, CaI2 · 8H2O, CaI2 · 7H2O and CaI2 · 6.5H2O.

    PubMed

    Hennings, Erik; Schmidt, Horst; Voigt, Wolfgang

    2014-09-01

    Single crystals of calcium bromide enneahydrate, CaBr(2) · 9H2O, calcium iodide octahydrate, CaI(2) · 8H2O, calcium iodide heptahydrate, CaI(2) · 7H2O, and calcium iodide 6.5-hydrate, CaI(2) · 6.5H2O, were grown from their aqueous solutions at and below room temperature according to the solid-liquid phase diagram. The crystal structure of CaI(2) · 6.5H2O was redetermined. All four structures are built up from distorted Ca(H2O)8 antiprisms. The antiprisms of the iodide hydrate structures are connected either via trigonal-plane-sharing or edge-sharing, forming dimeric units. The antiprisms in calcium bromide enneahydrate are monomeric. PMID:25186361

  18. Neutron behavior, reactor control, and reactor heat transfer. Volume four

    SciTech Connect

    Not Available

    1986-01-01

    Volume four covers neutron behavior (neutron absorption, how big are nuclei, neutron slowing down, neutron losses, the self-sustaining reactor), reactor control (what is controlled in a reactor, controlling neutron population, is it easy to control a reactor, range of reactor control, what happens when the fuel burns up, controlling a PWR, controlling a BWR, inherent safety of reactors), and reactor heat transfer (heat generation in a nuclear reactor, how is heat removed from a reactor core, heat transfer rate, heat transfer properties of the reactor coolant).

  19. Reactor vessel support system

    DOEpatents

    Golden, Martin P.; Holley, John C.

    1982-01-01

    A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

  20. Nuclear reactor overflow line

    DOEpatents

    Severson, Wayne J.

    1976-01-01

    The overflow line for the reactor vessel of a liquid-metal-cooled nuclear reactor includes means for establishing and maintaining a continuous bleed flow of coolant amounting to 5 to 10% of the total coolant flow through the overflow line to prevent thermal shock to the overflow line when the reactor is restarted following a trip. Preferably a tube is disposed concentrically just inside the overflow line extending from a point just inside the reactor vessel to an overflow tank and a suction line is provided opening into the body of liquid metal in the reactor vessel and into the annulus between the overflow line and the inner tube.

  1. PUSH-PULL POWER REACTOR

    DOEpatents

    Froman, D.K.

    1959-02-24

    Power generating nuclear reactors of the homogeneous liquid fuel type are discussed. The apparatus utilizes two identical reactors interconnected by conduits through heat exchanging apparatus. Each reactor contains a critical geometry region and a vapor region separated from the critical region by a baffle. When the liquid in the first critical region becomes critical, the vapor pressure above the fuel is increased due to the rise in the temperature until it forces the liquid fuel out of the first critical region through the heat exchanger and into the second critical region, which is at a lower temperature and consequently a lower vapor pressure. The above reaction is repeated in the second critical region and the liquid fuel is forced back into the first critical region. In this manner criticality is achieved alternately in each critical region and power is extracted by the heat exchanger from the liquid fuel passing therethrough. The vapor region and the heat exchanger have a non-critical geometry and reactivity control is effected by conventional control rods in the critical regions.

  2. Reactor water cleanup system

    DOEpatents

    Gluntz, Douglas M.; Taft, William E.

    1994-01-01

    A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling.

  3. Reactor water cleanup system

    DOEpatents

    Gluntz, D.M.; Taft, W.E.

    1994-12-20

    A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling. 1 figure.

  4. Spinning fluids reactor

    DOEpatents

    Miller, Jan D; Hupka, Jan; Aranowski, Robert

    2012-11-20

    A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.

  5. Rodded shutdown system for a nuclear reactor

    DOEpatents

    Golden, Martin P.; Govi, Aldo R.

    1978-01-01

    A top mounted nuclear reactor diverse rodded shutdown system utilizing gas fed into a pressure bearing bellows region sealed at the upper extremity to an armature. The armature is attached to a neutron absorber assembly by a series of shafts and connecting means. The armature is held in an uppermost position by an electromagnet assembly or by pressurized gas in a second embodiment. Deenergizing the electromagnet assembly, or venting the pressurized gas, causes the armature to fall by the force of gravity, thereby lowering the attached absorber assembly into the reactor core.

  6. Global estimation of potential unreported plutonium in thermal research reactors

    SciTech Connect

    Dreicer, J.S.; Rutherford, D.A.

    1996-09-01

    As of November, 1993, 303 research reactors (research, test, training, prototype, and electricity producing) were operational worldwide; 155 of these were in non-nuclear weapon states. Of these 155 research reactors, 80 are thermal reactors that have a power rating of 1 MW(th) or greater and could be utilized to produce plutonium. A previously published study on the unreported plutonium production of six research reactors indicates that a minimum reactor power of 40 MW (th) is required to make a significant quantity (SQ), 8 kg, of fissile plutonium per year by unreported irradiations. As part of the Global Nuclear Material Control Model effort, we determined an upper bound on the maximum possible quantity of plutonium that could be produced by the 80 thermal research reactors in the non-nuclear weapon states (NNWS). We estimate that in one year a maximum of roughly one quarter of a metric ton (250 kg) of plutonium could be produced in these 80 NNWS thermal research reactors based on their reported power output. We have calculated the quantity of plutonium and the number of years that would be required to produce an SQ of plutonium in the 80 thermal research reactors and aggregated by NNWS. A safeguards approach for multiple thermal research reactors that can produce less than 1 SQ per year should be conducted in association with further developing a safeguards and design information reverification approach for states that have multiple research reactors.

  7. Reactor Coolant Pump seal issues and their applicability to new reactor designs

    SciTech Connect

    Ruger, C.J.; Higgins, J.C.

    1993-11-01

    Reactor Coolant Pumps (RCPs) of various types are used to circulate the primary coolant through the reactor in most reactor designs. RCPs generally contain mechanical seals to limit the leakage of pressurized reactor coolant along the pump drive shaft into the containment. The relatively large number of RCP seal and seal auxiliary system failures experienced at US operating plants during the 1970`s and early 1980`s raised concerns from the US Nuclear Regulatory Commission (NRC) that gross failures may lead to reactor core uncovery and subsequent core damage. Some seal failure events resulted in a loss of primary coolant to the containment at flow rates greater than the normal makeup capacity of Pressurized Water Reactor (PWR) plants. This is an example of RCP seal failures resulting in a small Loss of Coolant Accident (LOCA). This paper discusses observed and potential causes of RCP seal failure and the recommendations for limiting the likelihood of a seal induced small LOCA. Issues arising out of the research supporting these recommendations and subsequent public comments by the utility industry on them, serve as lessons learned, which are applicable to the design of new reactor plants.

  8. Utilities Expense Report.

    ERIC Educational Resources Information Center

    Moore, Deborah P.

    2001-01-01

    Examines how deregulation has affected school district utility costs. Offers ideas that can help school districts save money and energy. Provides several examples of state-wide initiatives intended to help school districts control utility costs. (GR)

  9. Research Utilization in Rehabilitation.

    ERIC Educational Resources Information Center

    Rogers, Everett M.

    In terms of its attention to research utilization, vocational rehabilitation today may be where agriculture was in 1913. One reason for this is an inadequate understanding of the process of research utilization. Scattered studies of research utilization have occurred, but suffer from a lack of integration. Among propositions that may be postulated…

  10. Sourcebook on Research Utilization.

    ERIC Educational Resources Information Center

    Rubin, Allen, Ed.; Rosenblatt, Aaron, Ed.

    Major papers presented at the Conference on Research Utilization in Social Work Education are compiled in this sourcebook. The conference focused on six topics that reviewed the state of the art of research utilization and suggested directions for the future. The papers included are: Understanding Research Utilization in Social Work (Stuart A.…

  11. Hybrid reactors. [Fuel cycle

    SciTech Connect

    Moir, R.W.

    1980-09-09

    The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW.m/sup -2/, and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are usually rapid.

  12. Improved vortex reactor system

    DOEpatents

    Diebold, J.P.; Scahill, J.W.

    1995-05-09

    An improved vortex reactor system is described for affecting fast pyrolysis of biomass and Refuse Derived Fuel (RDF) feed materials comprising: a vortex reactor having its axis vertically disposed in relation to a jet of a horizontally disposed steam ejector that impels feed materials from a feeder and solids from a recycle loop along with a motive gas into a top part of said reactor. 12 figs.

  13. FLOW SYSTEM FOR REACTOR

    DOEpatents

    Zinn, W.H.

    1963-06-11

    A reactor is designed with means for terminating the reaction when returning coolant is below a predetermined temperature. Coolant flowing from the reactor passes through a heat exchanger to a lower reservoir, and then circulates between the lower reservoir and an upper reservoir before being returned to the reactor. Means responsive to the temperature of the coolant in the return conduit terminate the chain reaction when the temperature reaches a predetermined minimum value. (AEC)

  14. The Integral Fast Reactor

    SciTech Connect

    Chang, Y.I.

    1988-01-01

    The Integral Fast Reactor (IFR) is an innovative liquid metal reactor concept being developed at Argonne National Laboratory. It seeks to specifically exploit the inherent properties of liquid metal cooling and metallic fuel in a way that leads to substantial improvements in the characteristics of the complete reactor system. This paper describes the key features and potential advantages of the IFR concept, with emphasis on its safety characteristics. 3 refs., 4 figs., 1 tab.

  15. NEUTRONIC REACTOR CONTROL

    DOEpatents

    Dreffin, R.S.

    1959-12-15

    A control means for a nuclear reactor is described. Particularly a device extending into the active portion of the reactor consisting of two hollow elements coaxially disposed and forming a channel therebetween, the cross sectional area of the channel increasing from each extremity of the device towards the center thereof. An element of neutron absorbing material is slidably positionable within the inner hollow element and a fluid reactor poison is introduced into the channel defined by the two hollow elements.

  16. Pressurized fluidized bed reactor

    DOEpatents

    Isaksson, J.

    1996-03-19

    A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine. 1 fig.

  17. Pressurized fluidized bed reactor

    DOEpatents

    Isaksson, Juhani

    1996-01-01

    A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine.

  18. Unconventional digital reactor control without conventional programming

    SciTech Connect

    Edwards, R.M.; Johns, R.M.; Kenney, S.J.

    1995-12-31

    Recent advances in simulation technology have resulted in the capability to design, test, and implement advanced control algorithms without the need for the labor-intensive effort of writing and debugging of computer programs. This technology has been adopted for a program of experimental development of power reactor control, which is jointly sponsored by the National Science Foundation and the Electric Power Research Institute. The experimental reactor control test bed utilizes the General Atomic Mark III TRIGA reactor at the Penn State Breazeale reactor facility. Control experiments are conducted within the movable experiment technical specifications of the TRIGA. A digital controller with an experimental control algorithm is interfaced to a secondary control rod (SCR). The new technology presented in this paper utilizes a UNIX network-compatible microprocessor-based controller operating under the Wind River Systems VxWorks real-time operating system. The controller interfaces with the Math-works MATLAB/SIMULINK development environment and Real-Time Innovations 8 monitoring software remotely operated on a SPARC workstation.

  19. Reactor-specific spent fuel discharge projections: 1986 to 2020

    SciTech Connect

    Heeb, C.M.; Walling, R.C.; Purcell, W.L.

    1987-03-01

    The creation of five reactor-specific spent fuel data bases that contain information on the projected amounts of spent fuel to be discharged from US commercial nuclear reactors through the year 2020 is described. The data bases contain detailed spent-fuel information from existing, planned, and projected pressurized water reactors (PWR) and boiling water reactors (BWR). The projections are based on individual reactor information supplied by the US reactor owners. The basic information is adjusted to conform to Energy Information Agency (EIA) forecasts for nuclear installed capacity, generation, and spent fuel discharged. The EIA cases considered are: (1) No new orders with extended burnup, (2) No new orders with constant burnup, (3) Upper reference (which assumes extended burnup), (4) Upper reference with constant burnup, and (5) Lower reference (which assumes extended burnup). Detailed, by-reactor tables are provided for annual discharged amounts of spent fuel, for storage requirements assuming maximum-at-reactor storage, and for storage requirements assuming maximum-at-reactor plus intra-utility transshipment of spent fuel. 6 refs., 8 figs., 8 tabs.

  20. Reactor-specific spent fuel discharge projections, 1987-2020

    SciTech Connect

    Walling, R.C.; Heeb, C.M.; Purcell, W.L.

    1988-03-01

    The creation of five reactor-specific spent fuel data bases that contain information on the projected amounts of spent fuel to be discharged from U.S. commercial nuclear reactors through the year 2020 is described. The data bases contain detailed spent fuel information from existing, planned, and projected pressurized water reactors (PWR) and boiling water eactors (BWR), and one existing high temperature gas reactor (HTGR). The projections are based on individual reactor information supplied by the U.S. reactor owners. The basic information is adjusted to conform to Energy Information Administration (EIA) forecasts for nuclear installed capacity, generation, and spent fuel discharged. The EIA cases considered are: No New Orders (assumes increasing burnup), No New Orders with No Increased Burnup, Upper Reference (assumes increasing burnup), Upper Reference with No Increased Burnup, and Lower Reference (assumes increasing burnup). Detailed, by-reactor tables are provided for annual discharged amounts of spent fuel, for storage requirements assuming maximum at-reactor storage, and for storage requirements assuming maximum at-reactor storage plus intra-utility transshipment of spent fuel. 8 refs., 8 figs., 10 tabs.

  1. NEUTRONIC REACTOR SYSTEM

    DOEpatents

    Treshow, M.

    1959-02-10

    A reactor system incorporating a reactor of the heterogeneous boiling water type is described. The reactor is comprised essentially of a core submerged adwater in the lower half of a pressure vessel and two distribution rings connected to a source of water are disposed within the pressure vessel above the reactor core, the lower distribution ring being submerged adjacent to the uppcr end of the reactor core and the other distribution ring being located adjacent to the top of the pressure vessel. A feed-water control valve, responsive to the steam demand of the load, is provided in the feedwater line to the distribution rings and regulates the amount of feed water flowing to each distribution ring, the proportion of water flowing to the submerged distribution ring being proportional to the steam demand of the load. This invention provides an automatic means exterior to the reactor to control the reactivity of the reactor over relatively long periods of time without relying upon movement of control rods or of other moving parts within the reactor structure.

  2. Operating US power reactors

    SciTech Connect

    Silver, E.G.

    1982-07-01

    The operation of US power reactors during March and April 1982 is summarized. Events of special note are discussed in the text, and the operational performance of all licensed power reactors is presented. These data are taken from the monthly Operating Units Status Report prepared by the Nuclear Regulatory Commission (NRC).

  3. Light water reactor program

    SciTech Connect

    Franks, S.M.

    1994-12-31

    The US Department of Energy`s Light Water Reactor Program is outlined. The scope of the program consists of: design certification of evolutionary plants; design, development, and design certification of simplified passive plants; first-of-a-kind engineering to achieve commercial standardization; plant lifetime improvement; and advanced reactor severe accident program. These program activities of the Office of Nuclear Energy are discussed.

  4. Polymerization Reactor Engineering.

    ERIC Educational Resources Information Center

    Skaates, J. Michael

    1987-01-01

    Describes a polymerization reactor engineering course offered at Michigan Technological University which focuses on the design and operation of industrial polymerization reactors to achieve a desired degree of polymerization and molecular weight distribution. Provides a list of the course topics and assigned readings. (TW)

  5. The Integral Fast Reactor

    SciTech Connect

    Till, C.E.; Chang, Y.I. ); Lineberry, M.J. )

    1990-01-01

    Argonne National Laboratory, since 1984, has been developing the Integral Fast Reactor (IFR). This paper will describe the way in which this new reactor concept came about; the technical, public acceptance, and environmental issues that are addressed by the IFR; the technical progress that has been made; and our expectations for this program in the near term. 5 refs., 3 figs.

  6. Pneumatic Planetary Regolith Feed System for In-Situ Resource Utilization

    NASA Technical Reports Server (NTRS)

    Mantovani, James G.; Mueller, Robert P.; Townsend, Ivan I.; Craft, Jack; Zacny, Kris

    2010-01-01

    The NASA In-situ Resource Utilization (ISRU) project requires a regolith feed system that can transfer lunar regolith several meters vertically into a chemical reactor for oxygen production on the moon.

  7. The Ohio State University Reactor Sharing Program [August 15, 2000 - May 31, 2001

    SciTech Connect

    Myser, Richard D.

    2002-01-04

    During the period from August 15, 2000 through may 31, 2001 the Ohio State University (OSU) Research Reactor participated in the Reactor Sharing Program by providing services to nine colleges and universities and four secondary school organizations. A total of about 17 faculty and 170 students utilized their facilities. The staff of the OSU Research Reactor is generally involved in four types of experiments at the Nuclear Reactor Laboratory. Included are introductions to nuclear research, neutron activation analysis, material irradiation, and classes that measure various reactor parameters.

  8. Status of French reactors

    SciTech Connect

    Ballagny, A.

    1997-08-01

    The status of French reactors is reviewed. The ORPHEE and RHF reactors can not be operated with a LEU fuel which would be limited to 4.8 g U/cm{sup 3}. The OSIRIS reactor has already been converted to LEU. It will use U{sub 3}Si{sub 2} as soon as its present stock of UO{sub 2} fuel is used up, at the end of 1994. The decision to close down the SILOE reactor in the near future is not propitious for the start of a conversion process. The REX 2000 reactor, which is expected to be commissioned in 2005, will use LEU (except if the fast neutrons core option is selected). Concerning the end of the HEU fuel cycle, the best option is reprocessing followed by conversion of the reprocessed uranium to LEU.

  9. Reactor neutrino monitoring

    NASA Astrophysics Data System (ADS)

    Lhuillier, D.

    2009-03-01

    Nuclear reactors are the most intense man-controlled sources of antineutrinos and as such have hosted number of key physics experiments, from the antineutrino discovery to modern oscillation measurements. At the present time, both detection technology and understanding of fundamental physics are mature enough to think about antineutrinos as a new tool for reactor monitoring. We describe below how antineutrinos can provide online information on reactor operation and amount of plutonium accumulated in the core. Reactors are the only sources of plutonium on earth and this element can be chemically separated from the rest of the nuclear fuel and diverted into nuclear weapons. We present in the next sections the unique features antineutrino detectors could provide to safeguards agencies such as IAEA. We review the worldwide efforts to develop small ( 1m scale) antineutrino detectors dedicated to automated and non-intrusive reactor monitoring.

  10. REACTOR FUEL SCAVENGING MEANS

    DOEpatents

    Coffinberry, A.S.

    1962-04-10

    A process for removing fission products from reactor liquid fuel without interfering with the reactor's normal operation or causing a significant change in its fuel composition is described. The process consists of mixing a liquid scavenger alloy composed of about 44 at.% plutoniunm, 33 at.% lanthanum, and 23 at.% nickel or cobalt with a plutonium alloy reactor fuel containing about 3 at.% lanthanum; removing a portion of the fuel and scavenger alloy from the reactor core and replacing it with an equal amount of the fresh scavenger alloy; transferring the portion to a quiescent zone where the scavenger and the plutonium fuel form two distinct liquid layers with the fission products being dissolved in the lanthanum-rich scavenger layer; and the clean plutonium-rich fuel layer being returned to the reactor core. (AEC)

  11. ETR BUILDING, TRA642, INTERIOR. FIRST FLOOR. INSIDE UTILITY CORRIDOR ALONG ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ETR BUILDING, TRA-642, INTERIOR. FIRST FLOOR. INSIDE UTILITY CORRIDOR ALONG SOUTH PERIMETER WALL (COMMON TO ELECTRICAL BUILDING, TRA-648). CAMERA FACES WEST. INL NEGATIVE NO. HD46-16-2. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  12. Cogeneration and utility diversification

    SciTech Connect

    Duggan, M.M.

    1985-08-01

    Niagara Mohawk saw cogeneration and utility diversification as an opportunity to break away from the traditional model of a public utility and avoid the fate of the railroads. The author reviews how HYDRA-CO Enterprises evaluated the risks and opportunities of diversification and the steps it took to diversify, which included a joint venture cogeneration project. The company sees a future with ever expanding opportunities for utility subsidiaries for those with courage and imagination.

  13. Integrity of the reactor coolant boundary of the European pressurized water reactor (EPR)

    SciTech Connect

    Goetsch, D.; Bieniussa, K.; Schulz, H.; Jalouneix, J.

    1997-04-01

    This paper is an abstract of the work performed in the frame of the development of the IPSN/GRS approach in view of the EPR conceptual safety features. EPR is a pressurized water reactor which will be based on the experience gained by utilities and designers in France and in Germany. The reactor coolant boundary of a PWR includes the reactor pressure vessel (RPV), those parts of the steam generators (SGs) which contain primary coolant, the pressurizer (PSR), the reactor coolant pumps (RCPs), the main coolant lines (MCLs) with their branches as well as the other connecting pipes and all branching pipes including the second isolation valves. The present work covering the integrity of the reactor coolant boundary is mainly restricted to the integrity of the main coolant lines (MCLs) and reflects the design requirements for the main components of the reactor coolant boundary. In the following the conceptual aspects, i.e. design, manufacture, construction and operation, will be assessed. A main aspect is the definition of break postulates regarding overall safety implications.

  14. Spectral structure of electron antineutrinos from nuclear reactors.

    PubMed

    Dwyer, D A; Langford, T J

    2015-01-01

    Recent measurements of the positron energy spectrum obtained from inverse beta decay interactions of reactor electron antineutrinos show an excess in the 4 to 6 MeV region relative to current predictions. First-principles calculations of fission and beta decay processes within a typical pressurized water reactor core identify prominent fission daughter isotopes as a possible origin for this excess. These calculations also predict percent-level substructures in the antineutrino spectrum due to Coulomb effects in beta decay. Precise measurement of these substructures can elucidate the nuclear processes occurring within reactors. These substructures can be a systematic issue for measurements utilizing the detailed spectral shape. PMID:25615462

  15. Strengthening the nuclear-reactor fuel cycle against proliferation

    SciTech Connect

    Travelli, A.; Snelgrove, J.; Persiani, P.

    1992-12-31

    Argonne National Laboratory (ANL) conducts several research programs that serve to reduce the risks of fissile-material diversion from the nuclear-reactor fuel cycle. The objectives are to provide economical and efficient neutron or power generation with the minimum of inherent risks, and to further minimize risks by utilizing sophisticated techniques to detect attempts at material diversion. This paper will discuss the Reduced Enrichment Research and Test Reactor (RERTR) Program, the Isotope Correlation Technique (ICT), and Proliferation-Resistant Closed-Cycle Reactors. The first two are sponsored by the DOE Office of Arms Control and Nonproliferation.

  16. Utilities weather the storm

    SciTech Connect

    Lihach, N.

    1984-11-01

    Utilities must restore power to storm-damaged transmission and distribution systems, even if it means going out in ice storms or during lightning and hurricane conditions. Weather forecasting helps utilities plan for possible damage as well as alerting them to long-term trends. Storm planning includes having trained repair personnel available and adjusting the system so that less power imports are needed. Storm damage response requires teamwork and cooperation between utilities. Utilities can strengthen equipment in storm-prone or vulnerable areas, but good data are necessary to document the incidence of lighning strikes, hurricanes, etc. 2 references, 8 figures.

  17. Extending the maximum operation time of the MNSR reactor.

    PubMed

    Dawahra, S; Khattab, K; Saba, G

    2016-09-01

    An effective modification to extend the maximum operation time of the Miniature Neutron Source Reactor (MNSR) to enhance the utilization of the reactor has been tested using the MCNP4C code. This modification consisted of inserting manually in each of the reactor inner irradiation tube a chain of three polyethylene-connected containers filled of water. The total height of the chain was 11.5cm. The replacement of the actual cadmium absorber with B(10) absorber was needed as well. The rest of the core structure materials and dimensions remained unchanged. A 3-D neutronic model with the new modifications was developed to compare the neutronic parameters of the old and modified cores. The results of the old and modified core excess reactivities (ρex) were: 3.954, 6.241 mk respectively. The maximum reactor operation times were: 428, 1025min and the safety reactivity factors were: 1.654 and 1.595 respectively. Therefore, a 139% increase in the maximum reactor operation time was noticed for the modified core. This increase enhanced the utilization of the MNSR reactor to conduct a long time irradiation of the unknown samples using the NAA technique and increase the amount of radioisotope production in the reactor. PMID:27442985

  18. Nuclear Education and Training Programs of Potential Interest to Utilities.

    ERIC Educational Resources Information Center

    Atomic Energy Commission, Washington, DC.

    This compilation of education and training programs related to nuclear applications in electric power generation covers programs conducted by nuclear reactor vendors, public utilities, universities, technical institutes, and community colleges, which were available in December 1968. Several training-program consultant services are also included.…

  19. Dynamic analysis of process reactors

    SciTech Connect

    Shadle, L.J.; Lawson, L.O.; Noel, S.D.

    1995-06-01

    The approach and methodology of conducting a dynamic analysis is presented in this poster session in order to describe how this type of analysis can be used to evaluate the operation and control of process reactors. Dynamic analysis of the PyGas{trademark} gasification process is used to illustrate the utility of this approach. PyGas{trademark} is the gasifier being developed for the Gasification Product Improvement Facility (GPIF) by Jacobs-Siffine Engineering and Riley Stoker. In the first step of the analysis, process models are used to calculate the steady-state conditions and associated sensitivities for the process. For the PyGas{trademark} gasifier, the process models are non-linear mechanistic models of the jetting fluidized-bed pyrolyzer and the fixed-bed gasifier. These process sensitivities are key input, in the form of gain parameters or transfer functions, to the dynamic engineering models.

  20. Inspecting the reactor vessel penetrations

    SciTech Connect

    Bodson, F.; Fleming, K.W.

    1995-08-01

    The susceptibility of Alloy 600 to Primary Water Stress Corrosion Cracking (PWSCC) continues to plague nuclear power plants. Recently, the problem of PWSCC cracking has manifested itself in Control Rod Drive Mechanism (CRDM) head penetrations in nuclear plants in Europe. Framatome has been extensively involved in the performance of both inspections and repairs of CRDM head penetrations at Electricite de France (EdF) plants. B and W Nuclear Technologies (BWNT), building on Framatome technology, has developed a fully integrated service package and robotic manipulator to inspect and repair CRDM head penetrations for US utilities. Reactor vessel bottom penetration are also made of Alloy 600 and to tackle this potential PWSCC problem at EdF plants, Framatome has been performing specific inspections in order to detect the appearance of the phenomenon. This paper describes the overall range of inspection techniques and toolings developed to address these issues.

  1. FUEL ELEMENT FOR NUCLEAR REACTORS

    DOEpatents

    Dickson, J.J.

    1963-09-24

    A method is described whereby fuel tubes or pins are cut, loaded with fuel pellets and a heat transfer medium, sealed at each end with slotted fittings, and assembled into a rectangular tube bundle to form a fuel element. The tubes comprising the fuel element are laterally connected between their ends by clips and tabs to form a linear group of spaced parallel tubes, which receive their vertical support by resting on a grid. The advantages of this method are that it permits elimination of structural material (e.g., fuel-element cans) within the reactor core, and removal of at least one fuel pin from an element and replacement thereof so that a burnable poison may be utilized during the core lifetime. (AEC)

  2. Coacervates as prebiotic chemical reactors

    NASA Astrophysics Data System (ADS)

    Kolb, Vera M.; Swanson, Mercedes; Menger, Fredric M.

    2012-10-01

    Coacervates are colloidal systems that are comprised of two immiscible aqueous layers, the colloid-rich layer, so-called coacervate, and the colloid-poor layer, so-called equilibrium liquid. Although immiscible, the two phases are both water-rich. Coacervates are important for prebiotic chemistry, but also have various practical applications, notably as transport vehicles of personal care products and pharmaceuticals. Our objectives are to explore the potential of coacervates as prebiotic chemical reactors. Since the reaction medium in coacervates is water, this creates a challenge, since most organic reactants are not water-soluble. To overcome this challenge we are utilizing recent Green Chemistry examples of the organic reactions in water, such as the Passerini reaction. We have investigated this reaction in two coacervate systems, and report here our preliminary results.

  3. Nanoparticles of [Fe(NH2-trz)3]Br2.3H2O (NH2-trz=2-amino-1,2,4-triazole) prepared by the reverse micelle technique: influence of particle and coherent domain sizes on spin-crossover properties.

    PubMed

    Forestier, Thibaut; Kaiba, Abdellah; Pechev, Stanislav; Denux, Dominique; Guionneau, Philippe; Etrillard, Céline; Daro, Nathalie; Freysz, Eric; Létard, Jean-François

    2009-06-15

    This paper describes the synthesis of iron(II) spin-crossover nanoparticles prepared by the reverse micelle technique by using the non-ionic surfactant Lauropal (Ifralan D0205) from the polyoxyethylenic family. By changing the surfactant/water ratio, the size of the particles of [Fe(NH2-trz)3]Br2.3H2O (with NH2trz=4-amino-1,2,4-triazole) can be controlled. On the macroscopic scale this complex exhibits cooperative thermal spin crossovers at 305 and 320 K. We find that when the size is reduced down to 50 nm, the spin transition becomes gradual and no hysteresis can be detected. For our data it seems that the critical size, for which the existence of a thermal hysteresis can be detected, is around 50 nm. Interestingly, the change of the particle size induces almost no change in the temperature of the thermal spin transition. A systematic determination of coherent domain size carried out on the nanoparticles by powder X-ray diffraction indicates that at approximately 30 nm individual particles consist of one coherent domain. PMID:19504472

  4. Electric utilities and telecommunications

    SciTech Connect

    Moeller, J.W.

    1995-08-01

    Part I of this article will provide some background on the involvement of electric utilities in telecommunications. It will discuss the Power Radio Services, under which the FCC regulates radio communications of electric utilities, the pole attachment statute of the Communications Act, which authorized the FCC to regulate attachments of cable television cables to electric utility poles, and a recent Department of Energy (DOE) report on the need for a demonstration on the use of telecommunications for DSM. Part I will also discuss several recent developments relative to the Power Radio Services and the pole attachment statute. Part II will discuss electric utilities and telecommunications under PUHCA. It will outline the extensive and complex requirements of PUHCA that are applicable to public utility holding companies, as well as the specific requirements of PUHCA for the formation by public utility holding companies of subsidiaries to engage in telecommunications activities. It will also discuss the seven instances in the past decade in which the SEC has approved the formation by public utility holding companies of such subsidiaries. Part III of this article will discuss a principal obstacle to expanded electric utility involvement in telecommunications activities-a series of administrative and judicial decisions that illustrate the potential for dual regulation by the SEC and the FERC to result in confusion and inefficiencies. It will also discuss proposals in Congress to minimize this potential. Part IV will discuss House Bill 3636 and Senate Bill 1822 and their proposals to amend PUHCA to facilitate the formation or acquisition by public utility holding companies of non-utility subsidiaries to engage in telecommunications activities. It will also discuss their proposals to address the potential consequences of dual regulation by the SEC and the FERC of electric utilities involved in telecommunications.

  5. LIGHT WATER MODERATED NEUTRONIC REACTOR

    DOEpatents

    Christy, R.F.; Weinberg, A.M.

    1957-09-17

    A uranium fuel reactor designed to utilize light water as a moderator is described. The reactor core is in a tank at the bottom of a substantially cylindrical cross-section pit, the core being supported by an apertured grid member and comprised of hexagonal tubes each containing a pluralily of fuel rods held in a geometrical arrangement between end caps of the tubes. The end caps are apertured to permit passage of the coolant water through the tubes and the fuel elements are aluminum clad to prevent corrosion. The tubes are hexagonally arranged in the center of the tank providing an amulus between the core and tank wall which is filled with water to serve as a reflector. In use, the entire pit and tank are filled with water in which is circulated during operation by coming in at the bottom of the tank, passing upwardly through the grid member and fuel tubes and carried off near the top of the pit, thereby picking up the heat generated by the fuel elements during the fission thereof. With this particular design the light water coolant can also be used as the moderator when the uranium is enriched by fissionable isotope to an abundance of U/sup 235/ between 0.78% and 2%.

  6. Criticality of spent reactor fuel

    SciTech Connect

    Harris, D.R.

    1987-01-01

    The storage capacity of spent reactor fuel pools can be greatly increased by consolidation. In this process, the fuel rods are removed from reactor fuel assemblies and are stored in close-packed arrays in a canister or skeleton. An earlier study examined criticality consideration for consolidation of Westinghouse fuel, assumed to be fresh, in canisters at the Millstone-2 spent-fuel pool and in the General Electric IF-300 shipping cask. The conclusions were that the fuel rods in the canister are so deficient in water that they are adequately subcritical, both in normal and in off-normal conditions. One potential accident, the water spill event, remained unresolved in the earlier study. A methodology is developed here for spent-fuel criticality and is applied to the water spill event. The methodology utilizes LEOPARD to compute few-group cross sections for the diffusion code PDQ7, which then is used to compute reactivity. These codes give results for fresh fuel that are in good agreement with KENO IV-NITAWL Monte Carlo results, which themselves are in good agreement with continuous energy Monte Carlo calculations. These methodologies are in reasonable agreement with critical measurements for undepleted fuel.

  7. Validation of the neutron and gamma fields in the JSI TRIGA reactor using in-core fission and ionization chambers.

    PubMed

    Žerovnik, Gašper; Kaiba, Tanja; Radulović, Vladimir; Jazbec, Anže; Rupnik, Sebastjan; Barbot, Loïc; Fourmentel, Damien; Snoj, Luka

    2015-02-01

    CEA developed fission chambers and ionization chambers were utilized at the JSI TRIGA reactor to measure neutron and gamma fields. The measured axial fission rate distributions in the reactor core are generally in good agreement with the calculated values using the Monte Carlo model of the reactor thus verifying both the computational model and the fission chambers. In future, multiple absolutely calibrated fission chambers could be used for more accurate online reactor thermal power monitoring. PMID:25479432

  8. Instructional Facility Utilization.

    ERIC Educational Resources Information Center

    Kalamazoo Valley Community Coll., MI.

    Data describing campus facility use for instructional and related purposes for one week of activity in Fall 1978 were collected and evaluated at Kalamazoo Valley Community College. Four measures of space utilization were used: (1) percent of available time used; (2) percent of available space used; (3) percent of scheduled space utilized; and (4)…

  9. Teuchos Utility Package

    Energy Science and Technology Software Center (ESTSC)

    2004-03-01

    Teuchos is designed to provide portable, object-oriented tools for Trillnos developers and users. This includes templated wrappers to BLAS/LAPACK, a serial dense matrix class, a parameter list, XML parsing utilities, reference counted pointer (smart pointer) utilities, and more. These tools are designed to run on both serial and parallel computers.

  10. Nuclear reactor control column

    SciTech Connect

    Bachovchin, D.M.

    1982-08-10

    The nuclear reactor control column comprises a column disposed within the nuclear reactor core having a variable cross-section hollow channel and containing balls whose vertical location is determined by the flow of the reactor coolant through the column. The control column is divided into three basic sections wherein each of the sections has a different cross-sectional area. The uppermost section of the control column has the greatest crosssectional area, the intermediate section of the control column has the smallest cross-sectional area, and the lowermost section of the control column has the intermediate cross-sectional area. In this manner, the area of the uppermost section can be established such that when the reactor coolant is flowing under normal conditions therethrough, the absorber balls will be lifted and suspended in a fluidized bed manner in the upper section. However, when the reactor coolant flow falls below a predetermined value, the absorber balls will fall through the intermediate section and into the lowermost section, thereby reducing the reactivity of the reactor core and shutting down the reactor.

  11. Nuclear reactor control column

    DOEpatents

    Bachovchin, Dennis M.

    1982-01-01

    The nuclear reactor control column comprises a column disposed within the nuclear reactor core having a variable cross-section hollow channel and containing balls whose vertical location is determined by the flow of the reactor coolant through the column. The control column is divided into three basic sections wherein each of the sections has a different cross-sectional area. The uppermost section of the control column has the greatest cross-sectional area, the intermediate section of the control column has the smallest cross-sectional area, and the lowermost section of the control column has the intermediate cross-sectional area. In this manner, the area of the uppermost section can be established such that when the reactor coolant is flowing under normal conditions therethrough, the absorber balls will be lifted and suspended in a fluidized bed manner in the upper section. However, when the reactor coolant flow falls below a predetermined value, the absorber balls will fall through the intermediate section and into the lowermost section, thereby reducing the reactivity of the reactor core and shutting down the reactor.

  12. Reactor Safety Research Programs

    SciTech Connect

    Edler, S. K.

    1981-07-01

    This document summarizes the work performed by Pacific Northwest Laboratory (PNL) from January 1 through March 31, 1981, for the Division of Reactor Safety Research within the U.S. Nuclear Regulatory Commission (NRC). Evaluations of nondestructive examination (NDE) techniques and instrumentation are reported; areas of investigation include demonstrating the feasibility of determining the strength of structural graphite, evaluating the feasibility of detecting and analyzing flaw growth in reactor pressure boundary systems, examining NDE reliability and probabilistic fracture mechanics, and assessing the integrity of pressurized water reactor (PWR) steam generator tubes where service-induced degradation has been indicated. Experimental data and analytical models are being provided to aid in decision-making regarding pipeto- pipe impacts following postulated breaks in high-energy fluid system piping. Core thermal models are being developed to provide better digital codes to compute the behavior of full-scale reactor systems under postulated accident conditions. Fuel assemblies and analytical support are being provided for experimental programs at other facilities. These programs include loss-ofcoolant accident (LOCA) simulation tests at the NRU reactor, Chalk River, Canada; fuel rod deformation, severe fuel damage, and postaccident coolability tests for the ESSOR reactor Super Sara Test Program, Ispra, Italy; the instrumented fuel assembly irradiation program at Halden, Norway; and experimental programs at the Power Burst Facility, Idaho National Engineering Laboratory (INEL). These programs will provide data for computer modeling of reactor system and fuel performance during various abnormal operating conditions.

  13. Slurry reactor design studies

    SciTech Connect

    Fox, J.M.; Degen, B.D.; Cady, G.; Deslate, F.D.; Summers, R.L. ); Akgerman, A. ); Smith, J.M. )

    1990-06-01

    The objective of these studies was to perform a realistic evaluation of the relative costs of tublar-fixed-bed and slurry reactors for methanol, mixed alcohols and Fischer-Tropsch syntheses under conditions where they would realistically be expected to operate. The slurry Fischer-Tropsch reactor was, therefore, operated at low H{sub 2}/CO ratio on gas directly from a Shell gasifier. The fixed-bed reactor was operated on 2.0 H{sub 2}/CO ratio gas after adjustment by shift and CO{sub 2} removal. Every attempt was made to give each reactor the benefit of its optimum design condition and correlations were developed to extend the models beyond the range of the experimental pilot plant data. For the methanol design, comparisons were made for a recycle plant with high methanol yield, this being the standard design condition. It is recognized that this is not necessarily the optimum application for the slurry reactor, which is being proposed for a once-through operation, coproducing methanol and power. Consideration is also given to the applicability of the slurry reactor to mixed alcohols, based on conditions provided by Lurgi for an Octamix{trademark} plant using their standard tubular-fixed reactor technology. 7 figs., 26 tabs.

  14. REACTOR BASE, SOUTHEAST CORNER. INTERIOR WILL CONTAIN REACTOR TANK, COOLING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    REACTOR BASE, SOUTHEAST CORNER. INTERIOR WILL CONTAIN REACTOR TANK, COOLING WATER PIPES, COOLING AIR DUCTS, AND SHIELDING. INL NEGATIVE NO. 776. Unknown Photographer, 10/1950 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  15. Benchmarking NSP Reactors with CORETRAN-01

    SciTech Connect

    Hines, Donald D.; Grow, Rodney L.; Agee, Lance J

    2004-10-15

    As part of an overall verification and validation effort, the Electric Power Research Institute's (EPRIs) CORETRAN-01 has been benchmarked against Northern States Power's Prairie Island and Monticello reactors through 12 cycles of operation. The two Prairie Island reactors are Westinghouse 2-loop units with 121 asymmetric 14 x 14 lattice assemblies utilizing up to 8 wt% gadolinium while Monticello is a General Electric 484 bundle boiling water reactor. All reactor cases were executed in full core utilizing 24 axial nodes per assembly in the fuel with 1 additional reflector node above, below, and around the perimeter of the core. Cross-section sets used in this benchmark effort were generated by EPRI's CPM-3 as well as Studsvik's CASMO-3 and CASMO-4 to allow for separation of the lattice calculation effect from the nodal simulation method. These cases exercised the depletion-shuffle-depletion sequence through four cycles for each unit using plant data to follow actual operations. Flux map calculations were performed for comparison to corresponding measurement statepoints. Additionally, start-up physics testing cases were used to predict cycle physics parameters for comparison to existing plant methods and measurements.These benchmark results agreed well with both current analysis methods and plant measurements, indicating that CORETRAN-01 may be appropriate for steady-state physics calculations of both the Prairie Island and Monticello reactors. However, only the Prairie Island results are discussed in this paper since Monticello results were of similar quality and agreement. No attempt was made in this work to investigate CORETRAN-01 kinetics capability by analyzing plant transients, but these steady-state results form a good foundation for moving in that direction.

  16. Neutronic analysis of a fusion hybrid reactor

    SciTech Connect

    Kammash, T.

    2012-07-01

    In a PHYSOR 2010 paper(1) we introduced a fusion hybrid reactor whose fusion component is the gasdynamic mirror (GDM), and whose blanket was made of thorium - 232. The thrust of that study was to demonstrate the performance of such a reactor by establishing the breeding of uranium - 233 in the blanket, and the burning thereof to produce power. In that analysis, we utilized the diffusion equation for one-energy neutron group, namely, those produced by the fusion reactions, to establish the power distribution and density in the system. Those results should be viewed as a first approximation since the high energy neutrons are not effective in inducing fission, but contribute primarily to the production of actinides. In the presence of a coolant, however, such as water, these neutrons tend to thermalize rather quickly, hence a better assessment of the reactor performance would require at least a two group analysis, namely the fast and thermal groups. We follow that approach and write an approximate set of equations for the fluxes of these groups. From these relations we deduce the all-important quantity, k{sub eff}, which we utilize to compute the multiplication factor, and subsequently, the power density in the reactor. We show that k{sub eff} can be made to have a value of 0.99, thus indicating that 100 thermal neutrons are generated per fusion neutron, while allowing the system to function as 'subcritical.' Moreover, we show that such a hybrid reactor can generate hundreds of megawatts of thermal power per cm of length depending on the flux of the fusion neutrons impinging on the blanket. (authors)

  17. Fast Breeder Reactor studies

    SciTech Connect

    Till, C.E.; Chang, Y.I.; Kittel, J.H.; Fauske, H.K.; Lineberry, M.J.; Stevenson, M.G.; Amundson, P.I.; Dance, K.D.

    1980-07-01

    This report is a compilation of Fast Breeder Reactor (FBR) resource documents prepared to provide the technical basis for the US contribution to the International Nuclear Fuel Cycle Evaluation. The eight separate parts deal with the alternative fast breeder reactor fuel cycles in terms of energy demand, resource base, technical potential and current status, safety, proliferation resistance, deployment, and nuclear safeguards. An Annex compares the cost of decommissioning light-water and fast breeder reactors. Separate abstracts are included for each of the parts.

  18. Reactor safety assessment system

    SciTech Connect

    Sebo, D.E.; Bray, M.A.; King, M.A.

    1987-01-01

    The Reactor Safety Assessment System (RSAS) is an expert system under development for the United States Nuclear Regulatory Commission (USNRC). RSA is designed for use at the USNRC Operations Center in the event of a serious incident at a licensed nuclear power plant. RSAS is a situation assessment expert system which uses plant parametric data to generate conclusions for use by the NRC Reactor Safety Team. RSAS uses multiple rule bases and plant specific setpoint files to be applicable to all licensed nuclear power plants in the United States. RSAS currently covers several generic reactor categories and multiple plants within each category.

  19. Spherical torus fusion reactor

    DOEpatents

    Martin Peng, Y.K.M.

    1985-10-03

    The object of this invention is to provide a compact torus fusion reactor with dramatic simplification of plasma confinement design. Another object of this invention is to provide a compact torus fusion reactor with low magnetic field and small aspect ratio stable plasma confinement. In accordance with the principles of this invention there is provided a compact toroidal-type plasma confinement fusion reactor in which only the indispensable components inboard of a tokamak type of plasma confinement region, mainly a current conducting medium which carries electrical current for producing a toroidal magnet confinement field about the toroidal plasma region, are retained.

  20. NEUTRONIC REACTOR CONTROL

    DOEpatents

    Metcalf, H.E.

    1958-10-14

    Methods of controlling reactors are presented. Specifically, a plurality of neutron absorber members are adjustably disposed in the reactor core at different distances from the center thereof. The absorber members extend into the core from opposite faces thereof and are operated by motive means coupled in a manner to simultaneously withdraw at least one of the absorber members while inserting one of the other absorber members. This feature effects fine control of the neutron reproduction ratio by varying the total volume of the reactor effective in developing the neutronic reaction.

  1. Microfluidic electrochemical reactors

    DOEpatents

    Nuzzo, Ralph G.; Mitrovski, Svetlana M.

    2011-03-22

    A microfluidic electrochemical reactor includes an electrode and one or more microfluidic channels on the electrode, where the microfluidic channels are covered with a membrane containing a gas permeable polymer. The distance between the electrode and the membrane is less than 500 micrometers. The microfluidic electrochemical reactor can provide for increased reaction rates in electrochemical reactions using a gaseous reactant, as compared to conventional electrochemical cells. Microfluidic electrochemical reactors can be incorporated into devices for applications such as fuel cells, electrochemical analysis, microfluidic actuation, pH gradient formation.

  2. NUCLEAR REACTOR FUEL SYSTEMS

    DOEpatents

    Thamer, B.J.; Bidwell, R.M.; Hammond, R.P.

    1959-09-15

    Homogeneous reactor fuel solutions are reported which provide automatic recombination of radiolytic gases and exhibit large thermal expansion characteristics, thereby providing stability at high temperatures and enabling reactor operation without the necessity of apparatus to recombine gases formed by the radiolytic dissociation of water in the fuel and without the necessity of liquid fuel handling outside the reactor vessel except for recovery processes. The fuels consist of phosphoric acid and water solutions of enriched uranium, wherein the uranium is in either the hexavalent or tetravalent state.

  3. Nuclear reactor reflector

    DOEpatents

    Hopkins, Ronald J.; Land, John T.; Misvel, Michael C.

    1994-01-01

    A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled.

  4. Nuclear reactor reflector

    DOEpatents

    Hopkins, R.J.; Land, J.T.; Misvel, M.C.

    1994-06-07

    A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled. 12 figs.

  5. CONTROL FOR NEUTRONIC REACTOR

    DOEpatents

    Lichtenberger, H.V.; Cameron, R.A.

    1959-03-31

    S>A control rod operating device in a nuclear reactor of the type in which the control rod is gradually withdrawn from the reactor to a position desired during stable operation is described. The apparatus is comprised essentially of a stop member movable in the direction of withdrawal of the control rod, a follower on the control rod engageable with the stop and means urging the follower against the stop in the direction of withdrawal. A means responsive to disengagement of the follower from the stop is provided for actuating the control rod to return to the reactor shut-down position.

  6. REACTOR CONTROL SYSTEM

    DOEpatents

    MacNeill, J.H.; Estabrook, J.Y.

    1960-05-10

    A reactor control system including a continuous tape passing through a first coolant passageway, over idler rollers, back through another parallel passageway, and over motor-driven rollers is described. Discrete portions of fuel or poison are carried on two opposed active sections of the tape. Driving the tape in forward or reverse directions causes both active sections to be simultaneously inserted or withdrawn uniformly, tending to maintain a more uniform flux within the reactor. The system is particularly useful in mobile reactors, where reduced inertial resistance to control rod movement is important.

  7. Control console replacement at the WPI Reactor. [Final report

    SciTech Connect

    Not Available

    1992-12-31

    With partial funding from the Department of Energy (DOE) University Reactor Instrumentation Upgrade Program (DOE Grant No. DE-FG02-90ER12982), the original control console at the Worcester Polytechnic Institute (WPI) Reactor has been replaced with a modern system. The new console maintains the original design bases and functionality while utilizing current technology. An advanced remote monitoring system has been added to augment the educational capabilities of the reactor. Designed and built by General Electric in 1959, the open pool nuclear training reactor at WPI was one of the first such facilities in the nation located on a university campus. Devoted to undergraduate use, the reactor and its related facilities have been since used to train two generations of nuclear engineers and scientists for the nuclear industry. The reactor power level was upgraded from 1 to 10 kill in 1969, and its operating license was renewed for 20 years in 1983. In 1988, the reactor was converted to low enriched uranium. The low power output of the reactor and ergonomic facility design make it an ideal tool for undergraduate nuclear engineering education and other training.

  8. Submerged bed versus unsaturated flow reactor: A pressurized hydrogenotrophic denitrification reactor as a case study.

    PubMed

    Epsztein, Razi; Beliavski, Michael; Tarre, Sheldon; Green, Michal

    2016-10-01

    The paper compares the main features of a submerged bed reactor (SuBR) with bubbling and recirculation of gas to those of an unsaturated flow reactor (uSFR) with liquid recirculation. A novel pressurized closed-headspace hydrogenotrophic denitrification system characterized by safe and economic utilization of H2 gas was used for the comparison. Under similar conditions, denitrification rates were lower in the SuBR as a result of a lower effective biofilm surface area and overall gas-liquid mass transfer coefficient kLa. Similar values of effluent DOC were achieved for both reactors, although effluent suspended solids concentration of the SuBR were substantially higher. On the other hand, the required cleaning frequency in the SuBR was 2.5 times lower. Moreover, the SuBR is expected to reduce the recirculation energy consumption by 0.35 kWh/m(3) treated. PMID:27424057

  9. Reactor hot spot analysis

    SciTech Connect

    Vilim, R.B.

    1985-08-01

    The principle methods for performing reactor hot spot analysis are reviewed and examined for potential use in the Applied Physics Division. The semistatistical horizontal method is recommended for future work and is now available as an option in the SE2-ANL core thermal hydraulic code. The semistatistical horizontal method is applied to a small LMR to illustrate the calculation of cladding midwall and fuel centerline hot spot temperatures. The example includes a listing of uncertainties, estimates for their magnitudes, computation of hot spot subfactor values and calculation of two sigma temperatures. A review of the uncertainties that affect liquid metal fast reactors is also presented. It was found that hot spot subfactor magnitudes are strongly dependent on the reactor design and therefore reactor specific details must be carefully studied. 13 refs., 1 fig., 5 tabs.

  10. Packed Bed Reactor Experiment

    NASA Video Gallery

    The purpose of the Packed Bed Reactor Experiment in low gravity is to determine how a mixture of gas and liquid flows through a packed bed in reduced gravity. A packed bed consists of a metal pipe ...

  11. NEUTRONIC REACTOR STRUCTURE

    DOEpatents

    Daniels, F.

    1961-10-24

    A reactor core, comprised of vertical stacks of hexagonal blocks of beryllium oxide having axial cylindrical apertures extending therethrough and cylindrical rods of a sintered mixture of uranium dioxide and beryllium oxide, is described. (AEC)

  12. Research Reactor Benchmarks

    SciTech Connect

    Ravnik, Matjaz; Jeraj, Robert

    2003-09-15

    A criticality benchmark experiment performed at the Jozef Stefan Institute TRIGA Mark II research reactor is described. This experiment and its evaluation are given as examples of benchmark experiments at research reactors. For this reason the differences and possible problems compared to other benchmark experiments are particularly emphasized. General guidelines for performing criticality benchmarks in research reactors are given. The criticality benchmark experiment was performed in a normal operating reactor core using commercially available fresh 20% enriched fuel elements containing 12 wt% uranium in uranium-zirconium hydride fuel material. Experimental conditions to minimize experimental errors and to enhance computer modeling accuracy are described. Uncertainties in multiplication factor due to fuel composition and geometry data are analyzed by sensitivity analysis. The simplifications in the benchmark model compared to the actual geometry are evaluated. Sample benchmark calculations with the MCNP and KENO Monte Carlo codes are given.

  13. Electric Utility Observers' Forum

    SciTech Connect

    Smartt, L.E.

    1982-05-13

    This second Observers' Forum of Public Utilities Fortnightly includes invited comments from 19 key legislators, utility consultants, and recognized figures in service industries on any subject to which the contributor wished to direct the attention of the industry leadership and which has a public-interest aspect. Participants were free to point to what they think the industry is doing, either right or wrong, and to areas where the industry might improve its performance. There is no single overriding message, but there is a prevalent mood that the electric-utility industry may have turned a corner despite some remaining problems.

  14. US Department of Energy 1992--1993 Reactor Sharing Program. Final report

    SciTech Connect

    Vernetson, W.G.

    1994-04-01

    The University of Florida Training Reactor serves as a host institution to support various educational institutions which are located primarily within the state of Florida. All users and uses were carefully screened to assure the usage was for educational institutions eligible for participation in the Reactor Sharing Program. Three tables are included that provide basic information about the 1992--1993 program and utilization of the reactor facilities by user institutions.

  15. Advances in Process Intensification through Multifunctional Reactor Engineering

    SciTech Connect

    O'Hern, Timothy; Evans, Lindsay; Miller, Jim; Cooper, Marcia; Torczynski, John; Pena, Donovan; Gill, Walt

    2011-02-01

    This project was designed to advance the art of process intensification leading to a new generation of multifunctional chemical reactors utilizing pulse flow. Experimental testing was performed in order to fully characterize the hydrodynamic operating regimes associated with pulse flow for implementation in commercial applications. Sandia National Laboratories (SNL) operated a pilot-scale multifunctional reactor experiment for operation with and investigation of pulse flow operation. Validation-quality data sets of the fluid dynamics, heat and mass transfer, and chemical kinetics were acquired and shared with Chemical Research and Licensing (CR&L). Experiments in a two-phase air-water system examined the effects of bead diameter in the packing, and viscosity. Pressure signals were used to detect pulsing. Three-phase experiments used immiscible organic and aqueous liquids, and air or nitrogen as the gas phase. Hydrodynamic studies of flow regimes and holdup were performed for different types of packing, and mass transfer measurements were performed for a woven packing. These studies substantiated the improvements in mass transfer anticipated for pulse flow in multifunctional reactors for the acid-catalyzed C4 paraffin/olefin alkylation process. CR&L developed packings for this alkylation process, utilizing their alkylation process pilot facilities in Pasadena, TX. These packings were evaluated in the pilot-scale multifunctional reactor experiments established by Sandia to develop a more fundamental understanding of their role in process intensification. Lummus utilized the alkylation technology developed by CR&L to design and optimize the full commercial process utilizing multifunctional reactors containing the packings developed by CR&L and evaluated by Sandia. This hydrodynamic information has been developed for multifunctional chemical reactors utilizing pulse flow, for the acid-catalyzed C4 paraffin/olefin alkylation process, and is now accessible for use in

  16. Advances in Process Intensification through Multifunctional Reactor Engineering

    SciTech Connect

    O'Hern, Timothy; Evans, Lindsay; Miller, Jim; Cooper, Marcia; Torczynski, John; Pena, Donovan; Gill, Walt; Groten, Will; Judzis, Arvids; Foley, Richard; Smith, Larry; Cross, Will; Vogt, T.

    2011-06-27

    This project was designed to advance the art of process intensification leading to a new generation of multifunctional chemical reactors utilizing pulse flow. Experimental testing was performed in order to fully characterize the hydrodynamic operating regimes associated with pulse flow for implementation in commercial applications. Sandia National Laboratories (SNL) operated a pilot-scale multifunctional reactor experiment for operation with and investigation of pulse flow operation. Validation-quality data sets of the fluid dynamics, heat and mass transfer, and chemical kinetics were acquired and shared with Chemical Research and Licensing (CR&L). Experiments in a two-phase air-water system examined the effects of bead diameter in the packing, and viscosity. Pressure signals were used to detect pulsing. Three-phase experiments used immiscible organic and aqueous liquids, and air or nitrogen as the gas phase. Hydrodynamic studies of flow regimes and holdup were performed for different types of packing, and mass transfer measurements were performed for a woven packing. These studies substantiated the improvements in mass transfer anticipated for pulse flow in multifunctional reactors for the acid-catalyzed C4 paraffin/olefin alkylation process. CR&L developed packings for this alkylation process, utilizing their alkylation process pilot facilities in Pasadena, TX. These packings were evaluated in the pilot-scale multifunctional reactor experiments established by Sandia to develop a more fundamental understanding of their role in process intensification. Lummus utilized the alkylation technology developed by CR&L to design and optimize the full commercial process utilizing multifunctional reactors containing the packings developed by CR&L and evaluated by Sandia. This hydrodynamic information has been developed for multifunctional chemical reactors utilizing pulse flow, for the acid-catalyzed C4 paraffin/olefin alkylation process, and is now accessible for use in

  17. Compact power reactor

    DOEpatents

    Wetch, Joseph R.; Dieckamp, Herman M.; Wilson, Lewis A.

    1978-01-01

    There is disclosed a small compact nuclear reactor operating in the epithermal neutron energy range for supplying power at remote locations, as for a satellite. The core contains fuel moderator elements of Zr hydride with 7 w/o of 93% enriched uranium alloy. The core has a radial beryllium reflector and is cooled by liquid metal coolant such as NaK. The reactor is controlled and shut down by moving portions of the reflector.

  18. Nuclear reactor control

    SciTech Connect

    Ingham, R.V.

    1980-01-01

    A liquid metal cooled fast breeder nuclear reactor has power setback means for use in an emergency. On initiation of a trip-signal a control rod is injected into the core in two stages, firstly, by free fall to effect an immediate power-set back to a safe level and, secondly, by controlled insertion. Total shut-down of the reactor under all emergencies is avoided. 4 claims.

  19. Molten metal reactors

    SciTech Connect

    Bingham, Dennis N; Klingler, Kerry M; Turner, Terry D; Wilding, Bruce M

    2013-11-05

    A molten metal reactor for converting a carbon material and steam into a gas comprising hydrogen, carbon monoxide, and carbon dioxide is disclosed. The reactor includes an interior crucible having a portion contained within an exterior crucible. The interior crucible includes an inlet and an outlet; the outlet leads to the exterior crucible and may comprise a diffuser. The exterior crucible may contain a molten alkaline metal compound. Contained between the exterior crucible and the interior crucible is at least one baffle.

  20. Future reactor experiments

    NASA Astrophysics Data System (ADS)

    Wen, Liangjian

    2015-07-01

    The non-zero neutrino mixing angle θ13 has been discovered and precisely measured by the current generation short-baseline reactor neutrino experiments. It opens the gate of measuring the leptonic CP-violating phase and enables the neutrino mass ordering. The JUNO and RENO-50 proposals aim at resolving the neutrino mass ordering using reactors. The experiment design, physics sensitivity, technical challenges as well as the progresses of those two proposed experiments are reviewed in this paper.

  1. Future reactor experiments

    SciTech Connect

    Wen, Liangjian

    2015-07-15

    The non-zero neutrino mixing angle θ{sub 13} has been discovered and precisely measured by the current generation short-baseline reactor neutrino experiments. It opens the gate of measuring the leptonic CP-violating phase and enables the neutrino mass ordering. The JUNO and RENO-50 proposals aim at resolving the neutrino mass ordering using reactors. The experiment design, physics sensitivity, technical challenges as well as the progresses of those two proposed experiments are reviewed in this paper.

  2. Moon base reactor system

    NASA Technical Reports Server (NTRS)

    Chavez, H.; Flores, J.; Nguyen, M.; Carsen, K.

    1989-01-01

    The objective of our reactor design is to supply a lunar-based research facility with 20 MW(e). The fundamental layout of this lunar-based system includes the reactor, power conversion devices, and a radiator. The additional aim of this reactor is a longevity of 12 to 15 years. The reactor is a liquid metal fast breeder that has a breeding ratio very close to 1.0. The geometry of the core is cylindrical. The metallic fuel rods are of beryllium oxide enriched with varying degrees of uranium, with a beryllium core reflector. The liquid metal coolant chosen was natural lithium. After the liquid metal coolant leaves the reactor, it goes directly into the power conversion devices. The power conversion devices are Stirling engines. The heated coolant acts as a hot reservoir to the device. It then enters the radiator to be cooled and reenters the Stirling engine acting as a cold reservoir. The engines' operating fluid is helium, a highly conductive gas. These Stirling engines are hermetically sealed. Although natural lithium produces a lower breeding ratio, it does have a larger temperature range than sodium. It is also corrosive to steel. This is why the container material must be carefully chosen. One option is to use an expensive alloy of cerbium and zirconium. The radiator must be made of a highly conductive material whose melting point temperature is not exceeded in the reactor and whose structural strength can withstand meteor showers.

  3. Reactor Safety Research Programs

    SciTech Connect

    Dotson, CW

    1980-08-01

    This document summarizes the work performed by Pacific Northwest laboratory from October 1 through December 31, 1979, for the Division of Reactor Safety Research within the Nuclear Regulatory Commission. Evaluation of nondestructive examination (NDE) techniques and instrumentation are reported; areas of investigation include demonstrating the feasibilty of determining structural graphite strength, evaluating the feasibilty of detecting and analyzing flaw growth in reactor pressure boundary systems, examining NDE reliability and probabilistic fracture mechanics, and assessing the remaining integrity of pressurized water reactor steam generator tubes where service-induced degradation has been indicated. Test assemblies and analytical support are being provided for experimental programs at other facilities. These programs include the loss-of-coolant accident simulation tests at the NRU reactor, Chalk River, Canada; the fuel rod deformation and post-accident coolability tests for the ESSOR Test Reactor Program, lspra, Italy; the blowdown and reflood tests in the test facility at Cadarache, France; the instrumented fuel assembly irradiation program at Halden, Norway; and the experimental programs at the Power Burst Facility, Idaho National Engineering Laboratory. These programs will provide data for computer modeling of reactor system and fuel performance during various abnormal operating conditions.

  4. F Reactor Inspection

    SciTech Connect

    Grindstaff, Keith; Hathaway, Boyd; Wilson, Mike

    2014-10-29

    Workers from Mission Support Alliance, LLC., removed the welds around the steel door of the F Reactor before stepping inside the reactor to complete its periodic inspection. This is the first time the Department of Energy (DOE) has had the reactor open since 2008. The F Reactor is one of nine reactors along the Columbia River at the Department's Hanford Site in southeastern Washington State, where environmental cleanup has been ongoing since 1989. As part of the Tri-Party Agreement, the Department completes surveillance and maintenance activities of cocooned reactors periodically to evaluate the structural integrity of the safe storage enclosure and to ensure confinement of any remaining hazardous materials. "This entry marks a transition of sorts because the Hanford Long-Term Stewardship Program, for the first time, was responsible for conducting the entry and surveillance and maintenance activities," said Keith Grindstaff, Energy Department Long-Term Stewardship Program Manager. "As the River Corridor cleanup work is completed and transitioned to long-term stewardship, our program will manage any on-going requirements."

  5. F Reactor Inspection

    ScienceCinema

    Grindstaff, Keith; Hathaway, Boyd; Wilson, Mike

    2014-11-24

    Workers from Mission Support Alliance, LLC., removed the welds around the steel door of the F Reactor before stepping inside the reactor to complete its periodic inspection. This is the first time the Department of Energy (DOE) has had the reactor open since 2008. The F Reactor is one of nine reactors along the Columbia River at the Department's Hanford Site in southeastern Washington State, where environmental cleanup has been ongoing since 1989. As part of the Tri-Party Agreement, the Department completes surveillance and maintenance activities of cocooned reactors periodically to evaluate the structural integrity of the safe storage enclosure and to ensure confinement of any remaining hazardous materials. "This entry marks a transition of sorts because the Hanford Long-Term Stewardship Program, for the first time, was responsible for conducting the entry and surveillance and maintenance activities," said Keith Grindstaff, Energy Department Long-Term Stewardship Program Manager. "As the River Corridor cleanup work is completed and transitioned to long-term stewardship, our program will manage any on-going requirements."

  6. New measurement system for on line in core high-energy neutron flux monitoring in materials testing reactor conditions

    SciTech Connect

    Geslot, B.; Filliatre, P.; Barbot, L.; Jammes, C.; Breaud, S.; Oriol, L.; Villard, J.-F.; Lopez, A. Legrand

    2011-03-15

    Flux monitoring is of great interest for experimental studies in material testing reactors. Nowadays, only the thermal neutron flux can be monitored on line, e.g., using fission chambers or self-powered neutron detectors. In the framework of the Joint Instrumentation Laboratory between SCK-CEN and CEA, we have developed a fast neutron detector system (FNDS) capable of measuring on line the local high-energy neutron flux in fission reactor core and reflector locations. FNDS is based on fission chambers measurements in Campbelling mode. The system consists of two detectors, one detector being mainly sensitive to fast neutrons and the other one to thermal neutrons. On line data processing uses the CEA depletion code DARWIN in order to disentangle fast and thermal neutrons components, taking into account the isotopic evolution of the fissile deposit. The first results of FNDS experimental test in the BR2 reactor are presented in this paper. Several fission chambers have been irradiated up to a fluence of about 7 x 10{sup 20} n/cm{sup 2}. A good agreement (less than 10% discrepancy) was observed between FNDS fast flux estimation and reference flux measurement.

  7. SPAR data handling utilities

    NASA Technical Reports Server (NTRS)

    Giles, G. L.; Haftka, R. T.

    1978-01-01

    The SPAR computer software system is a collection of processors that perform particular steps in the finite-element structural analysis procedure. The data generated by each processor are stored on a data base complex residing on an auxiliary storage device, and these data are then used by subsequent processors. The SPAR data handling utilities use routines to transfer data between the processors and the data base complex. A detailed description of the data base complex organization is presented. A discussion of how these SPAR data handling utilities are used in an application program to perform desired user functions is given with the steps necessary to convert an existing program to a SPAR processor by incorporating these utilities. Finally, a sample SPAR processor is included to illustrate the use of the data handling utilities.

  8. PAM stack test utility

    Energy Science and Technology Software Center (ESTSC)

    2007-08-22

    The pamtest utility calls the normal PAM hooks using a service and username supplied on the command line. This allows an administratory to test any one of many configured PAM stacks as any existing user on the machine.

  9. NEUTRONIC REACTOR CONSTRUCTION AND OPERATION

    DOEpatents

    West, J.M.; Weills, J.T.

    1960-03-15

    A method is given for operating a nuclear reactor having a negative coefficient of reactivity to compensate for the change in reactor reactivity due to the burn-up of the xenon peak following start-up of the reactor. When it is desired to start up the reactor within less than 72 hours after shutdown, the temperature of the reactor is lowered prior to start-up, and then gradually raised after start-up.

  10. 10 CFR 50.46a - Acceptance criteria for reactor coolant system venting systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Acceptance criteria for reactor coolant system venting systems. 50.46a Section 50.46a Energy NUCLEAR REGULATORY COMMISSION DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION FACILITIES Standards for Licenses, Certifications, and Regulatory Approvals § 50.46a Acceptance criteria for reactor coolant...

  11. 10 CFR Appendix H to Part 50 - Reactor Vessel Material Surveillance Program Requirements

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Reactor Vessel Material Surveillance Program Requirements H Appendix H to Part 50 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION FACILITIES Pt. 50, App. H Appendix H to Part 50—Reactor Vessel Material Surveillance Program Requirements I. Introduction II....

  12. 10 CFR Appendix H to Part 50 - Reactor Vessel Material Surveillance Program Requirements

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Reactor Vessel Material Surveillance Program Requirements H Appendix H to Part 50 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION FACILITIES Pt. 50, App. H Appendix H to Part 50—Reactor Vessel Material Surveillance Program Requirements I. Introduction II....

  13. 10 CFR Appendix H to Part 50 - Reactor Vessel Material Surveillance Program Requirements

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Reactor Vessel Material Surveillance Program Requirements H Appendix H to Part 50 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION FACILITIES Pt. 50, App. H Appendix H to Part 50—Reactor Vessel Material Surveillance Program Requirements I. Introduction II....

  14. 10 CFR Appendix H to Part 50 - Reactor Vessel Material Surveillance Program Requirements

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Reactor Vessel Material Surveillance Program Requirements H Appendix H to Part 50 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION FACILITIES Pt. 50, App. H Appendix H to Part 50—Reactor Vessel Material Surveillance Program Requirements I. Introduction II....

  15. 10 CFR Appendix H to Part 50 - Reactor Vessel Material Surveillance Program Requirements

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Reactor Vessel Material Surveillance Program Requirements H Appendix H to Part 50 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION FACILITIES Pt. 50, App. H Appendix H to Part 50—Reactor Vessel Material Surveillance Program Requirements I. Introduction II....

  16. 10 CFR 50.44 - Combustible gas control for nuclear power reactors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Combustible gas control for nuclear power reactors. 50.44 Section 50.44 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION... for nuclear power reactors. (a) Definitions—(1) Inerted atmosphere means a containment atmosphere...

  17. 10 CFR 50.44 - Combustible gas control for nuclear power reactors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Combustible gas control for nuclear power reactors. 50.44 Section 50.44 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION... for nuclear power reactors. (a) Definitions—(1) Inerted atmosphere means a containment atmosphere...

  18. Technology Implementation Plan. Fully Ceramic Microencapsulated Fuel for Commercial Light Water Reactor Application

    SciTech Connect

    Snead, Lance Lewis; Terrani, Kurt A.; Powers, Jeffrey J.; Worrall, Andrew; Robb, Kevin R.; Snead, Mary A.

    2015-04-01

    This report is an overview of the implementation plan for ORNL's fully ceramic microencapsulated (FCM) light water reactor fuel. The fully ceramic microencapsulated fuel consists of tristructural isotropic (TRISO) particles embedded inside a fully dense SiC matrix and is intended for utilization in commercial light water reactor application.

  19. Application of MCNP for neutronic calculations at VR-1 training reactor

    NASA Astrophysics Data System (ADS)

    Huml, Ondřej; Rataj, Jan; Bílý, Tomáš

    2014-06-01

    The paper presents utilization of Monte Carlo MCNP transport code for neutronic calculations of training reactor VR-1. Results of calculations are compared with results of measurements realized during last few critical experiments with various reactor core configurations. Very good agreement between calculations and measurements is observed.

  20. 77 FR 38338 - Dairyland Power Cooperative; La Crosse Boiling Water Reactor Exemption From Certain Security...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-27

    ..., which utilized a forced-circulation, direct-cycle boiling water reactor as its heat source. The plant is... March 27, 2009 (74 FR 13926). The revised regulation stated that it was applicable to all Part 50... COMMISSION Dairyland Power Cooperative; La Crosse Boiling Water Reactor Exemption From Certain...

  1. Utility straight sections

    SciTech Connect

    Leemann, B.; Peggs, S.; Peterson, J.

    1985-10-01

    Utility straight sections are insertions in the SSC lattice to provide relatively free space to facilitate various beam manipulations. These uses include beam-abort, injection (and conceivably ejection), space for the rf system, and collimation. A typical utility straight section is 1500 meters in overall length (ranging from 500 to 1200 meters). It has zero dispersion and high values of the beta functions. The betatron phase shift across the insertion is about 90{degrees} in each plane.

  2. Praxis conversion utilities

    SciTech Connect

    Duffy, J.M.; Greenwood, J.R.; Shapiro, R.

    1981-12-02

    The Praxis Conversion Utilities are a set of Praxis routines which convert data objects to/from Ascii strings. For instance, the AsciiInteger function converts an array of characters to an integer value. These routines are implemented as a consistent set of utilities with complete control over the various formatting options and fill characters. Most of the parameters for each routine are optional such that they are easy to invoke for standard cases, yet allowing the detailed control when necessary.

  3. Liquid uranium alloy-helium fission reactor

    DOEpatents

    Minkov, Vladimir

    1986-01-01

    This invention teaches a nuclear fission reactor having a core vessel and at least one tandem heat exchanger vessel coupled therewith across upper and lower passages to define a closed flow loop. Nuclear fuel such as a uranium alloy in its liquid phase fills these vessels and flow passages. Solid control elements in the reactor core vessel are adapted to be adjusted relative to one another to control fission reaction of the liquid fuel therein. Moderator elements in the other vessel and flow passages preclude fission reaction therein. An inert gas such as helium is bubbled upwardly through the heat exchanger vessel operable to move the liquid fuel upwardly therein and unidirectionally around the closed loop and downwardly through the core vessel. This helium gas is further directed to heat conversion means outside of the reactor vessels to utilize the heat from the fission reaction to generate useful output. The nuclear fuel operates in the 1200.degree.-1800.degree. C. range, and even higher to 2500.degree. C., limited only by the thermal effectiveness of the structural materials, increasing the efficiency of power generation from the normal 30-35% with 300.degree.-500.degree. C. upper limit temperature to 50-65%. Irradiation of the circulating liquid fuel, as contrasted to only localized irradiation of a solid fuel, provides improved fuel utilization.

  4. MONTE CARLO SIMULATIONS OF PERIODIC PULSED REACTOR WITH MOVING GEOMETRY PARTS

    SciTech Connect

    Cao, Yan; Gohar, Yousry

    2015-11-01

    In a periodic pulsed reactor, the reactor state varies periodically from slightly subcritical to slightly prompt supercritical for producing periodic power pulses. Such periodic state change is accomplished by a periodic movement of specific reactor parts, such as control rods or reflector sections. The analysis of such reactor is difficult to perform with the current reactor physics computer programs. Based on past experience, the utilization of the point kinetics approximations gives considerable errors in predicting the magnitude and the shape of the power pulse if the reactor has significantly different neutron life times in different zones. To accurately simulate the dynamics of this type of reactor, a Monte Carlo procedure using the transfer function TRCL/TR of the MCNP/MCNPX computer programs is utilized to model the movable reactor parts. In this paper, two algorithms simulating the geometry part movements during a neutron history tracking have been developed. Several test cases have been developed to evaluate these procedures. The numerical test cases have shown that the developed algorithms can be utilized to simulate the reactor dynamics with movable geometry parts.

  5. Fuel Cycle Performance of Thermal Spectrum Small Modular Reactors

    SciTech Connect

    Worrall, Andrew; Todosow, Michael

    2016-01-01

    metrics for a small modular reactor are compared to a conventional three-batch light water reactor in the following areas: nuclear waste management, environmental impact, and resource utilization. Metrics performance for a small modular reactor are degraded for mass of spent nuclear fuel and high level waste disposed, mass of depleted uranium disposed, land use per energy generated, and carbon emission per energy generated

  6. Evaluation of Metal-Fueled Surface Reactor Concepts

    SciTech Connect

    Poston, David I.; Marcille, Thomas F.; Kapernick, Richard J.; Hiatt, Matthew T.; Amiri, Benjamin W.

    2007-01-30

    Surface fission power systems for use on the Moon and Mars may provide the first use of near-term reactor technology in space. Most near-term surface reactor concepts specify reactor temperatures <1000 K to allow the use of established material and power conversion technology and minimize the impact of the in-situ environment. Metal alloy fuels (e.g. U-10Zr and U-10Mo) have not traditionally been considered for space reactors because of high-temperature requirements, but they might be an attractive option for these lower temperature surface power missions. In addition to temperature limitations, metal fuels are also known to swell significantly at rather low fuel burnups ({approx}1 a/o), but near-term surface missions can mitigate this concern as well, because power and lifetime requirements generally keep fuel burnups <1 a/o. If temperature and swelling issues are not a concern, then a surface reactor concept may be able to benefit from the high uranium density and relative ease of manufacture of metal fuels. This paper investigates two reactor concepts that utilize metal fuels. It is found that these concepts compare very well to concepts that utilize other fuels (UN, UO2, UZrH) on a mass basis, while also providing the potential to simplify material safeguards issues.

  7. Proposed power upgrade of the Hot Fuel Examination Facility's neutron radiography reactor. [NRAD reactor

    SciTech Connect

    Pruett, D.P.; Richards, W.J.; Heidel, C.C.

    1984-01-01

    The Hot Fuel Examination Facility, HFEF, is one of several facilities located at the Argonne Site. HFEF comprises a large hot cell where both non-destructive and destructive examination of highly-irradiated reactor fuels are conducted in support of the LMFBR program. One of the non-destructive examination techniques utilized at HFEF is neutron radiography. Neutron radiography is provided by the NRAD reactor facility, which is located beneath the HFEF hot cell. The NRAD reactor is a TRIGA reactor and is operated at a steady state power level of 250 kW solely for neutron radiography and the development of radiography techniques. When the NRAD facility was designed and constructed, an operating power level of 250 kW was considered to be adequate for obtaining radiographs of the type of specimens envisaged at that time. A typical radiograph required approximately a twenty-minute exposure time. Specimens were typically single fuel rods placed in an aluminum tray. Since that time, however, several things have occurred that have tended to increase radiography exposure times to as much as 90 minutes each. In order to decrease exposure times, the reactor power level is to be increased from 250 kw to 1 MW. This increase in power will necessitate several engineering and design changes. These changes are described.

  8. REACTOR GROUT THERMAL PROPERTIES

    SciTech Connect

    Steimke, J.; Qureshi, Z.; Restivo, M.; Guerrero, H.

    2011-01-28

    Savannah River Site has five dormant nuclear production reactors. Long term disposition will require filling some reactor buildings with grout up to ground level. Portland cement based grout will be used to fill the buildings with the exception of some reactor tanks. Some reactor tanks contain significant quantities of aluminum which could react with Portland cement based grout to form hydrogen. Hydrogen production is a safety concern and gas generation could also compromise the structural integrity of the grout pour. Therefore, it was necessary to develop a non-Portland cement grout to fill reactors that contain significant quantities of aluminum. Grouts generate heat when they set, so the potential exists for large temperature increases in a large pour, which could compromise the integrity of the pour. The primary purpose of the testing reported here was to measure heat of hydration, specific heat, thermal conductivity and density of various reactor grouts under consideration so that these properties could be used to model transient heat transfer for different pouring strategies. A secondary purpose was to make qualitative judgments of grout pourability and hardened strength. Some reactor grout formulations were unacceptable because they generated too much heat, or started setting too fast, or required too long to harden or were too weak. The formulation called 102H had the best combination of characteristics. It is a Calcium Alumino-Sulfate grout that contains Ciment Fondu (calcium aluminate cement), Plaster of Paris (calcium sulfate hemihydrate), sand, Class F fly ash, boric acid and small quantities of additives. This composition afforded about ten hours of working time. Heat release began at 12 hours and was complete by 24 hours. The adiabatic temperature rise was 54 C which was within specification. The final product was hard and displayed no visible segregation. The density and maximum particle size were within specification.

  9. Reactor Safety Planning for Prometheus Project, for Naval Reactors Information

    SciTech Connect

    P. Delmolino

    2005-05-06

    The purpose of this letter is to submit to Naval Reactors the initial plan for the Prometheus project Reactor Safety work. The Prometheus project is currently developing plans for cold physics experiments and reactor prototype tests. These tests and facilities may require safety analysis and siting support. In addition to the ground facilities, the flight reactor units will require unique analyses to evaluate the risk to the public from normal operations and credible accident conditions. This letter outlines major safety documents that will be submitted with estimated deliverable dates. Included in this planning is the reactor servicing documentation and shipping analysis that will be submitted to Naval Reactors.

  10. Assessment of light water reactor accident management programs and experience

    SciTech Connect

    Hammersley, R.J.

    1992-03-01

    The objective of this report is to provide an assessment of the current light water reactor experience regarding accident management programs and associated technology developments. This assessment for light water reactor (LWR) designs is provided as a resource and reference for the development of accident management capabilities for the production reactors at the Savannah River Site. The specific objectives of this assessment are as follows: 1. Perform a review of the NRC, utility, and industry (NUMARC, EPRI) accident management programs and implementation experience. 2. Provide an assessment of the problems and opportunities in developing an accident management program in conjunction or following the Individual Plant Examination process. 3. Review current NRC, utility, and industry technological developments in the areas of computational tools, severe accident predictive tools, diagnostic aids, and severe accident training and simulation.

  11. Nuclear Safeguards Considerations For The Pebble Bed Modular Reactor (PBMR)

    SciTech Connect

    Phillip Casey Durst; David Beddingfield; Brian Boyer; Robert Bean; Michael Collins; Michael Ehinger; David Hanks; David L. Moses; Lee Refalo

    2009-10-01

    High temperature reactors (HTRs) have been considered since the 1940s, and have been constructed and demonstrated in the United Kingdom (Dragon), United States (Peach Bottom and Fort Saint Vrain), Japan (HTTR), Germany (AVR and THTR-300), and have been the subject of conceptual studies in Russia (VGM). The attraction to these reactors is that they can use a variety of reactor fuels, including abundant thorium, which upon reprocessing of the spent fuel can produce fissile U-233. Hence, they could extend the stocks of available uranium, provided the fuel is reprocessed. Another attractive attribute is that HTRs typically operate at a much higher temperature than conventional light water reactors (LWRs), because of the use of pyrolytic carbon and silicon carbide coated (TRISO) fuel particles embedded in ceramic graphite. Rather than simply discharge most of the unused heat from the working fluid in the power plant to the environment, engineers have been designing reactors for 40 years to recover this heat and make it available for district heating or chemical conversion plants. Demonstrating high-temperature nuclear energy conversion was the purpose behind Fort Saint Vrain in the United States, THTR-300 in Germany, HTTR in Japan, and HTR-10 and HTR-PM, being built in China. This resulted in nuclear reactors at least 30% or more thermodynamically efficient than conventional LWRs, especially if the waste heat can be effectively utilized in chemical processing plants. A modern variant of high temperature reactors is the Pebble Bed Modular Reactor (PBMR). Originally developed in the United States and Germany, it is now being redesigned and marketed by the Republic of South Africa and China. The team examined historical high temperature and high temperature gas reactors (HTR and HTGR) and reviewed safeguards considerations for this reactor. The following is a preliminary report on this topic prepared under the ASA-100 Advanced Safeguards Project in support of the NNSA Next

  12. Magnetic switch for reactor control rod

    DOEpatents

    Germer, John H.

    1986-01-01

    A magnetic reed switch assembly for activating an electromagnetic grapple utilized to hold a control rod in position above a reactor core. In normal operation the magnetic field of a permanent magnet is short-circuited by a magnetic shunt, diverting the magnetic field away from the reed switch. The magnetic shunt is made of a material having a Curie-point at the desired release temperature. Above that temperature the material loses its ferromagnetic properties, and the magnetic path is diverted to the reed switch which closes and short-circuits the control circuit for the control rod electromagnetic grapple which allows the control rod to drop into the reactor core for controlling the reactivity of the core.

  13. Magnetic switch for reactor control rod. [LMFBR

    DOEpatents

    Germer, J.H.

    1982-09-30

    A magnetic reed switch assembly is described for activating an electromagnetic grapple utilized to hold a control rod in position above a reactor core. In normal operation the magnetic field of a permanent magnet is short-circuited by a magnetic shunt, diverting the magnetic field away from the reed switch. The magnetic shunt is made of a material having a Curie-point at the desired release temperature. Above that temperature the material loses its ferromagnetic properties, and the magnetic path is diverted to the reed switch which closes and short-circuits the control circuit for the control rod electro-magnetic grapple which allows the control rod to drop into the reactor core for controlling the reactivity of the core.

  14. Plasma generators, reactor systems and related methods

    DOEpatents

    Kong, Peter C.; Pink, Robert J.; Lee, James E.

    2007-06-19

    A plasma generator, reactor and associated systems and methods are provided in accordance with the present invention. A plasma reactor may include multiple sections or modules which are removably coupled together to form a chamber. Associated with each section is an electrode set including three electrodes with each electrode being coupled to a single phase of a three-phase alternating current (AC) power supply. The electrodes are disposed about a longitudinal centerline of the chamber and are arranged to provide and extended arc and generate an extended body of plasma. The electrodes are displaceable relative to the longitudinal centerline of the chamber. A control system may be utilized so as to automatically displace the electrodes and define an electrode gap responsive to measure voltage or current levels of the associated power supply.

  15. Device and method for shortening reactor process tubes

    DOEpatents

    Frantz, Charles E.; Alexander, William K.; Lander, Walter E. B.

    1980-01-01

    This disclosure describes a device and method for in situ shortening of nuclear reactor zirconium alloy process tubes which have grown as a result of radiation exposure. An upsetting technique is utilized which involves inductively heating a short band of a process tube with simultaneous application of an axial load sufficient to cause upsetting with an attendant decrease in length of the process tube.

  16. Passive cooling system for nuclear reactor containment structure

    DOEpatents

    Gou, Perng-Fei; Wade, Gentry E.

    1989-01-01

    A passive cooling system for the contaminant structure of a nuclear reactor plant providing protection against overpressure within the containment attributable to inadvertent leakage or rupture of the system components. The cooling system utilizes natural convection for transferring heat imbalances and enables the discharge of irradiation free thermal energy to the atmosphere for heat disposal from the system.

  17. Natural circulating passive cooling system for nuclear reactor containment structure

    DOEpatents

    Gou, Perng-Fei; Wade, Gentry E.

    1990-01-01

    A passive cooling system for the contaminant structure of a nuclear reactor plant providing protection against overpressure within the containment attributable to inadvertent leakage or rupture of the system components. The cooling system utilizes natural convection for transferring heat imbalances and enables the discharge of irradiation free thermal energy to the atmosphere for heat disposal from the system.

  18. Utility terrestrial biodiversity issues

    SciTech Connect

    Breece, G.A.; Ward, B.J.

    1996-11-01

    Results from a survey of power utility biologists indicate that terrestrial biodiversity is considered a major issued by only a few utilities; however, a majority believe it may be a future issue. Over half of the respondents indicated that their company is involved in some management for biodiversity, and nearly all feel that it should be a goal for resource management. Only a few utilities are funding biodiversity research, but a majority felt more research was needed. Generally, larger utilities with extensive land holdings had greater opportunities and resources for biodiversity management. Biodiversity will most likely be a concern with transmission rights-of-way construction and maintenance, endangered species issues and general land resource management, including mining reclamation and hydro relicensing commitments. Over half of the companies surveyed have established voluntary partnerships with management groups, and biodiversity is a goal in nearly all the joint projects. Endangered species management and protection, prevention of forest fragmentation, wetland protection, and habitat creation and protection are the most common partnerships involving utility companies. Common management practices and unique approaches are presented, along with details of the survey. 4 refs.

  19. REACTOR AND NOVEL METHOD

    DOEpatents

    Young, G.J.; Ohlinger, L.A.

    1958-06-24

    A nuclear reactor of the type which uses a liquid fuel and a method of controlling such a reactor are described. The reactor is comprised essentially of a tank for containing the liquid fuel such as a slurry of discrete particles of fissionnble material suspended in a heavy water moderator, and a control means in the form of a disc of neutron absorbirg material disposed below the top surface of the slurry and parallel thereto. The diameter of the disc is slightly smaller than the diameter of the tank and the disc is perforated to permit a flow of the slurry therethrough. The function of the disc is to divide the body of slurry into two separate portions, the lower portion being of a critical size to sustain a nuclear chain reaction and the upper portion between the top surface of the slurry and the top surface of the disc being of a non-critical size. The method of operation is to raise the disc in the reactor until the lower portion of the slurry has reached a critical size when it is desired to initiate the reaction, and to lower the disc in the reactor to reduce the size of the lower active portion the slurry to below criticality when it is desired to stop the reaction.

  20. EBT reactor analysis

    SciTech Connect

    Uckan, N. A.; Jaeger, E. F.; Santoro, R. T.; Spong, D. A.; Uckan, T.; Owen, L. W.; Barnes, J. M.; McBride, J. B.

    1983-08-01

    This report summarizes the results of a recent ELMO Bumpy Torus (EBT) reactor study that includes ring and core plasma properties with consistent treatment of coupled ring-core stability criteria and power balance requirements. The principal finding is that constraints imposed by these coupling and other physics and technology considerations permit a broad operating window for reactor design optimization. Within this operating window, physics and engineering systems analysis and cost sensitivity studies indicate that reactors with <..beta../sub core/> approx. 6 to 10%, P approx. 1200 to 1700 MW(e), wall loading approx. 1.0 to 2.5 MW/m/sup 2/, and recirculating power fraction (including ring-sustaining power and all other reactors auxiliaries) approx. 10 to 15% are possible. A number of concept improvements are also proposed that are found to offer the potential for further improvement of the reactor size and parameters. These include, but are not limited to, the use of: (1) supplementary coils or noncircular mirror coils to improve magnetic geometry and reduce size, (2) energetic ion rings to improve ring power requirements, (3) positive potential to enhance confinement and reduce size, and (4) profile control to improve stability and overall fusion power density.

  1. Brewery wastewater treatment using anaerobic inverse fluidized bed reactors.

    PubMed

    Alvarado-Lassman, A; Rustrián, E; García-Alvarado, M A; Rodríguez-Jiménez, G C; Houbron, E

    2008-05-01

    Two anaerobic inverse fluidized bed reactors were utilized to evaluate organic matter removal from brewery wastewater, applying different OLR and testing two support materials. Hydrodynamic tests varying liquid flow and solid concentration were developed on the supports in order to establish operational conditions. A batch colonization stage was applied using 25% active volume of extendosphere and triturated polyethylene as support materials. The reactors were subsequently operated continuously with stepwise increments in organic loading rate until limiting conditions was reached. For the supports studied, IFBR technology was suitable for organic matter removal present in brewery wastewater with COD removal efficiencies greater than 90%. The reactor with triturated polyethylene support showed an excellent COD removal with OLR values up to 10 g COD/Ld, whereas the reactor with extendosphere support had an excellent hydrodynamic and biologic behavior working with OLR values up to 70 g COD/Ld. PMID:17716891

  2. WILDCAT: a catalyzed D-D tokamak reactor

    SciTech Connect

    Evans, K. Jr.; Baker, C.C.; Brooks, J.N.

    1981-11-01

    WILDCAT is a conceptual design of a catalyzed D-D, tokamak, commercial, fusion reactor. WILDCAT utilizes the beneficial features of no tritium breeding, while not extrapolating unnecessarily from existing D-T designs. The reactor is larger and has higher magnetic fields and plasma pressures than typical D-T devices. It is more costly, but eliminates problems associated with tritium breeding and has tritium inventories and throughputs approximately two orders of magnitude less than typical D-T reactors. There are both a steady-state version with Alfven-wave current drive and a pulsed version. Extensive comparison with D-T devices has been made, and cost and safety analyses have been included. All of the major reactor systems have been worked out to a level of detail appropriate to a complete, conceptual design.

  3. Simulated antineutrino signatures of nuclear reactors for nonproliferation applications

    NASA Astrophysics Data System (ADS)

    Misner, Alex C.

    2008-10-01

    Antineutrino detectors could provide a valuable addition to current safeguards regimes. Antineutrinos are an attractive emission to monitor due to their low interaction cross-section that prevents them from being shielded and the dependence of their spectrum on the power level and isotopic content of a reactor core. While there are antineutrino detectors currently deployed at an operational reactor, such observations cannot predict the effect of the diversion of nuclear material on the antineutrino emissions. Utilizing simulation tools, one can predict the antineutrino signatures of such abnormal operations and other reactor types that have not been experimentally measured. This study simulates reactor cores with assembly-level resolution for both baseline and diversion cases in order to predict the properties of a detector for measuring the differences in the antineutrino signatures.

  4. Methanation assembly using multiple reactors

    DOEpatents

    Jahnke, Fred C.; Parab, Sanjay C.

    2007-07-24

    A methanation assembly for use with a water supply and a gas supply containing gas to be methanated in which a reactor assembly has a plurality of methanation reactors each for methanating gas input to the assembly and a gas delivery and cooling assembly adapted to deliver gas from the gas supply to each of said methanation reactors and to combine water from the water supply with the output of each methanation reactor being conveyed to a next methanation reactor and carry the mixture to such next methanation reactor.

  5. Redeveloping utility plants

    SciTech Connect

    Gottlieb, J.W. )

    1994-01-01

    In 1987, Adirondack Hydro Development Corp., a Glens Falls, NY-based developer of independent hydropower projects, successfully won Niagara Mohawk's bid for proposals to redevelop the Middle Falls project. The benefits Adirondack Hydro offered Niagara Mohawk included savings in revenue requirements for the utility and its ratepayers, savings in avoided cost payments, avoidance of the risk associated with redeveloping the project, an increase in the generation and capacity of the project, and additional revenues for the utility through payments for the lease of the site. In return, Adirondack received a 40-year power purchase contract at competitive prices for any electricity generated by the project and a long-term source of income for the company and its shareholders. The redeveloped Middle Falls project has been generating electricity and providing benefits to Adirondack Hydro, Niagara Mohawk and its ratepayers since 1990. This example demonstrates an alternative for hydropower developers who are finding new project development problematic at best - especially in the United States. Federal regulatory initiatives and new state activism are combining to make greenfield development more difficult. Nevertheless, developers and utilities are exploring market niches for the deployment of new technologies and the opportunities for redevelopment and expanded operation of existing hydroelectric projects. At the same time, the new competitive utility marketplace has caused investor-owned utilities to explore ways to reduce or eliminate operating expenses on their systems in an effort to increase shareholder earnings while decreasing the cost of service. These elements have combined to create opportunities for the redevelopment of utility-owned hydroelectric projects such as was done with the Middle Falls Project.

  6. TMI-2 in-vessel hydraulic systems utilize high water and high boron content fluids

    SciTech Connect

    Baston, V.F.; Hofstetter, K.J.; Hofman, L.A.; Gallagher, R.E.

    1987-01-01

    Choice of a hydraulic fluid for use in the Three Mile Island Unit 2 (TMI-2) reactor vessel defueling equipment required consideration of the following constraints for the hydraulic fluid given an accidental spill into the reactor coolant system (RCS). The TMI-2 RCS hydraulic fluid utilized in the hydraulic operations utilized a solution composition of 95 wt% water and 5 wt% of the above base fluid. The TMI-2 hydraulic system utilizes pressures up to 3500 psi. The selected hydraulic fluid has been in use since December 1986 with minimal operational difficulties.

  7. Degradation of Acid Orange 7 Dye in Two Hybrid Plasma Discharge Reactors

    NASA Astrophysics Data System (ADS)

    Shen, Yongjun; Lei, Lecheng; Zhang, Xingwang; Ding, Jiandong

    2014-11-01

    To get an optimized pulsed electrical plasma discharge reactor and to increase the energy utilization efficiency in the removal of pollutants, two hybrid plasma discharge reactors were designed and optimized. The reactors were compared via the discharge characteristics, energy transfer efficiency, the yields of the active species and the energy utilization in dye wastewater degradation. The results showed that under the same AC input power, the characteristics of the discharge waveform of the point-to-plate reactor were better. Under the same AC input power, the two reactors both had almost the same peak voltage of 22 kV. The peak current of the point-to-plate reactor was 146 A, while that of the wire-to-cylinder reactor was only 48.8 A. The peak powers of the point-to-plate reactor and the wire-to-cylinder reactor were 1.38 MW and 1.01 MW, respectively. The energy per pulse of the point-to-plate reactor was 0.2221 J, which was about 29.4% higher than that of the wire-to-cylinder reactor (0.1716 J). To remove 50% Acid Orange 7 (AO7), the energy utilizations of the point-to-plate reactor and the wire-to-cylinder reactor were 1.02 × 10-9 mol/L and 0.61 × 10-9 mol/L, respectively. In the point-to-plate reactor, the concentration of hydrogen peroxide in pure water was 3.6 mmol/L after 40 min of discharge, which was higher than that of the wire-to-cylinder reactor (2.5 mmol/L). The concentration of liquid phase ozone in the point-to-plate reactor (5.7 × 10-2 mmol/L) was about 26.7% higher than that in the wire-to-cylinder reactor (4.5 × 10-2 mmol/L). The analysis results of the variance showed that the type of reactor and reaction time had significant impacts on the yields of the hydrogen peroxide and ozone. The main degradation intermediates of AO7 identified by gas chromatography and mass spectrometry (GCMS) were acetic acid, maleic anhydride, p-benzoquinone, phenol, benzoic acid, phthalic anhydride, coumarin and 2-naphthol. Proposed degradation pathways were

  8. Deregulation of electric utilities

    SciTech Connect

    Zaccour, G.

    1998-07-01

    This volume is a collection of fourteen, mainly applied, economic papers examining electric utility deregulation in many parts of the world. These papers were presented at the International Workshop on Deregulation of Electric Utilities held in Montreal, Canada in September 1997. As the title suggests, these papers cover a broad range of topics. Despite the book's scattershot approach, a small subset of contributors asks a fundamental question: Is the industry sufficiently deregulated? This book succeeds in providing some concrete and well-analyzed examples that examine this important question.

  9. Dynamic Response Testing in an Electrically Heated Reactor Test Facility

    NASA Technical Reports Server (NTRS)

    Bragg-Sitton, Shannon M.; Morton, T. J.

    2006-01-01

    Non-nuclear testing can be a valuable tool in development of a space nuclear power or propulsion system. In a non-nuclear test bed, electric heaters are used to simulate the heat from nuclear fuel. Standard testing allows one to fully assess thermal, heat transfer, and stress related attributes of a given system, but fails to demonstrate the dynamic response that would be present in an integrated, fueled reactor system. The integration of thermal hydraulic hardware tests with simulated neutronic response provides a bridge between electrically heated testing and full nuclear testing. By implementing a neutronic response model to simulate the dynamic response that would be expected in a fueled reactor system, one can better understand system integration issues, characterize integrated system response times and response characteristics, and assess potential design improvements at a relatively small fiscal investment. Initial system dynamic response testing was demonstrated on the integrated SAFE-100a heat pipe cooled, electrically heated reactor and heat exchanger hardware, utilizing a one-group solution to the point kinetics equations to simulate the expected neutronic response of the system (Bragg-Sitton, 2005). The current paper applies the same testing methodology to a direct drive gas cooled reactor system, demonstrating the applicability of the testing methodology to any reactor type and demonstrating the variation in system response characteristics in different reactor concepts. In each testing application, core power transients were controlled by a point kinetics model with reactivity feedback based on core average temperature; the neutron generation time and the temperature feedback coefficient are provided as model inputs. Although both system designs utilize a fast spectrum reactor, the method of cooling the reactor differs significantly, leading to a variable system response that can be demonstrated and assessed in a non-nuclear test facility.

  10. Merchant Marine Ship Reactor

    DOEpatents

    Sankovich, M. F.; Mumm, J. F.; North, Jr, D. C.; Rock, H. R.; Gestson, D. K.

    1961-05-01

    A nuclear reactor for use in a merchant marine ship is described. The reactor is of pressurized, light water cooled and moderated design in which three passes of the water through the core in successive regions of low, intermediate, and high heat generation and downflow in a fuel region are made. The design makes a compact reactor construction with extended core life. The core has an egg-crate lattice containing the fuel elements that are confined between a lower flow baffle and upper grid plate, with the latter serving also as part of a turn- around manifold from which the entire coolant is distributed into the outer fuel elements for the second pass through the core. The inner fuel elements are cooled in the third pass. (AEC)

  11. MERCHANT MARINE SHIP REACTOR

    DOEpatents

    Mumm, J.F.; North, D.C. Jr.; Rock, H.R.; Geston, D.K.

    1961-05-01

    A nuclear reactor is described for use in a merchant marine ship. The reactor is of pressurized light water cooled and moderated design in which three passes of the water through the core in successive regions of low, intermediate, and high heat generation and downflow in a fuel region are made. The foregoing design makes a compact reactor construction with extended core life. The core has an egg-crate lattice containing the fuel elements confined between a lower flow baffle and upper grid plate, with the latter serving also as part of a turn- around manifold from which the entire coolant is distributed into the outer fuel elements for the second pass through the core. The inner fuel elements are cooled in the third pass.

  12. Heat dissipating nuclear reactor

    DOEpatents

    Hunsbedt, A.; Lazarus, J.D.

    1985-11-21

    Disclosed is a nuclear reactor containment adapted to retain and cool core debris in the unlikely event of a core meltdown and subsequent breach in the reactor vessel. The reactor vessel is seated in a cavity which has a thick metal sidewall that is integral with a thick metal basemat at the bottom of the cavity. The basemat extends beyond the perimeter of the cavity sidewall. Underneath the basemat is a porous bed with water pipes and steam pipes running into it. Water is introduced into the bed and converted into steam which is vented to the atmosphere. A plurality of metal pilings in the form of H-beams extend from the metal base plate downwardly and outwardly into the earth.

  13. Heat dissipating nuclear reactor

    DOEpatents

    Hunsbedt, Anstein; Lazarus, Jonathan D.

    1987-01-01

    Disclosed is a nuclear reactor containment adapted to retain and cool core debris in the unlikely event of a core meltdown and subsequent breach in the reactor vessel. The reactor vessel is seated in a cavity which has a thick metal sidewall that is integral with a thick metal basemat at the bottom of the cavity. The basemat extends beyond the perimeter of the cavity sidewall. Underneath the basemat is a porous bed with water pipes and steam pipes running into it. Water is introduced into the bed and converted into steam which is vented to the atmosphere. A plurality of metal pilings in the form of H-beams extends from the metal base plate downwardly and outwardly into the earth.

  14. Dynamic bed reactor

    DOEpatents

    Stormo, Keith E.

    1996-07-02

    A dynamic bed reactor is disclosed in which a compressible open cell foam matrix is periodically compressed and expanded to move a liquid or fluid through the matrix. In preferred embodiments, the matrix contains an active material such as an enzyme, biological cell, chelating agent, oligonucleotide, adsorbent or other material that acts upon the liquid or fluid passing through the matrix. The active material may be physically immobilized in the matrix, or attached by covalent or ionic bonds. Microbeads, substantially all of which have diameters less than 50 microns, can be used to immobilize the active material in the matrix and further improve reactor efficiency. A particularly preferred matrix is made of open cell polyurethane foam, which adsorbs pollutants such as polychlorophenol or o-nitrophenol. The reactors of the present invention allow unidirectional non-laminar flow through the matrix, and promote intimate exposure of liquid reactants to active agents such as microorganisms immobilized in the matrix.

  15. Reactor for exothermic reactions

    DOEpatents

    Smith, L.A. Jr.; Hearn, D.; Jones, E.M. Jr.

    1993-03-02

    A liquid phase process is described for oligomerization of C[sub 4] and C[sub 5] isoolefins or the etherification thereof with C[sub 1] to C[sub 6] alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300 F. Wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

  16. Dynamic bed reactor

    SciTech Connect

    Stormo, K.E.

    1996-07-02

    A dynamic bed reactor is disclosed in which a compressible open cell foam matrix is periodically compressed and expanded to move a liquid or fluid through the matrix. In preferred embodiments, the matrix contains an active material such as an enzyme, biological cell, chelating agent, oligonucleotide, adsorbent or other material that acts upon the liquid or fluid passing through the matrix. The active material may be physically immobilized in the matrix, or attached by covalent or ionic bonds. Microbeads, substantially all of which have diameters less than 50 microns, can be used to immobilize the active material in the matrix and further improve reactor efficiency. A particularly preferred matrix is made of open cell polyurethane foam, which adsorbs pollutants such as polychlorophenol or o-nitrophenol. The reactors of the present invention allow unidirectional non-laminar flow through the matrix, and promote intimate exposure of liquid reactants to active agents such as microorganisms immobilized in the matrix. 27 figs.

  17. NUCLEAR REACTOR UNLOADING APPARATUS

    DOEpatents

    Leverett, M.C.; Howe, J.P.

    1959-01-20

    An unloading device is described for a heterogeneous reactor of the type wherein the fuel elements are in the form of cylindrical slugs and are disposed in horizontal coolant tubes which traverse the reactor core, coolant fluid being circulated through the tubes. The coolant tubes have at least two inwardly protruding ribs from their lower surfaces to support the slugs in spaced relationship to the inside walls of the tubes. The unloading device consists of a ribbon-like extractor member insertable into the coolant tubes in the space between the ribs and adapted to slide under the fuel slugs thereby raising them off of the ribs and forming a slideway for removing them from the reactor. The fuel slugs are ejected by being forced out of the tubes by incoming new fuel slugs or by a push rod insentable through the inlet end of the fuel tubes.

  18. A NEUTRONIC REACTOR

    DOEpatents

    Luebke, E.A.; Vandenberg, L.B.

    1959-09-01

    A nuclear reactor for producing thermoelectric power is described. The reactor core comprises a series of thermoelectric assemblies, each assembly including fissionable fuel as an active element to form a hot junction and a thermocouple. The assemblies are disposed parallel to each other to form spaces and means are included for Introducing an electrically conductive coolant between the assemblies to form cold junctions of the thermocouples. An electromotive force is developed across the entire series of the thermoelectric assemblies due to fission heat generated in the fuel causing a current to flow perpendicular to the flow of coolant and is distributed to a load outside of the reactor by means of bus bars electrically connected to the outermost thermoelectric assembly.

  19. Colliding Beam Fusion Reactors

    NASA Astrophysics Data System (ADS)

    Rostoker, Norman; Qerushi, Artan; Binderbauer, Michl

    2003-06-01

    The recirculating power for virtually all types of fusion reactors has previously been calculated [1] with the Fokker-Planck equation. The reactors involve non-Maxwellian plasmas. The calculations are generic in that they do not relate to specific confinement devices. In all cases except for a Tokamak with D-T fuel the recirculating power was found to exceed the fusion power by a large factor. In this paper we criticize the generality claimed for this calculation. The ratio of circulating power to fusion power is calculated for the Colliding Beam Reactor with fuels D-T, D-He3 and p-B11. The results are respectively, 0.070, 0.141 and 0.493.

  20. Thermionic Reactor Design Studies

    SciTech Connect

    Schock, Alfred

    1994-08-01

    Paper presented at the 29th IECEC in Monterey, CA in August 1994. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their (thermionic reactor) performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling.

  1. Hanford plots reactor move

    SciTech Connect

    King, H.

    1993-10-04

    Anxious to show skeptics some bang for the mounting cleanup bucks, the US Dept. of Energy has taken steps to get a large and visible project under way at its Hanford weapon plant-moving eight old nuclear reactors to permanent burial at an inland dump site. The effort, conservatively budgeted at $235 million, will be the eastern Washington site's largest [open quotes]D D[close quotes]-decontamination and decommissioning-project yet. Last month, DOE unveiled its final record of decision for the plants that spells out D D options-from doing nothing to immediate removal of entire reactor blocks. At issue are reactors built from 1943 to 1963 along the Columbia River. Defunct since 1971, they once produced plutonium.

  2. Nuclear reactor safety device

    DOEpatents

    Hutter, Ernest

    1986-01-01

    A safety device is disclosed for use in a nuclear reactor for axially repositioning a control rod with respect to the reactor core in the event of an upward thermal excursion. Such safety device comprises a laminated helical ribbon configured as a tube-like helical coil having contiguous helical turns with slidably abutting edges. The helical coil is disclosed as a portion of a drive member connected axially to the control rod. The laminated ribbon is formed of outer and inner laminae. The material of the outer lamina has a greater thermal coefficient of expansion than the material of the inner lamina. In the event of an upward thermal excursion, the laminated helical coil curls inwardly to a smaller diameter. Such inward curling causes the total length of the helical coil to increase by a substantial increment, so that the control rod is axially repositioned by a corresponding amount to reduce the power output of the reactor.

  3. Breazeale Reactor Modernization Program

    SciTech Connect

    Davison, C. C.

    2003-04-16

    The Penn State Breazeale Nuclear Reactor is the longest operating licensed research reactor in the nation. The facility has played a key role in educating scientists, engineers and in providing facilities and services to researchers in many different disciplines. In order to remain a viable and effective research and educational institution, a multi-phase modernization project was proposed. Phase I was the replacement of the 25-year old reactor control and safety system along with associated wiring and hardware. This phase was fully funded by non-federal funds. Tasks identified in Phases II-V expand upon and complement the work done in Phase I to strategically implement state-of-the-art technologies focusing on identified national needs and priorities of the future.

  4. Reactor for exothermic reactions

    DOEpatents

    Smith, Jr., Lawrence A.; Hearn, Dennis; Jones, Jr., Edward M.

    1993-01-01

    A liquid phase process for oligomerization of C.sub.4 and C.sub.5 isoolefins or the etherification thereof with C.sub.1 to C.sub.6 alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120.degree. to 300.degree. F. Wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

  5. REACTOR CONTROL DEVICE

    DOEpatents

    Graham, R.H.

    1962-09-01

    A wholly mechanical compact control device is designed for automatically rendering the core of a fission reactor subcritical in response to core temperatures in excess of the design operating temperature limit. The control device comprises an expansible bellows interposed between the base of a channel in a reactor core and the inner end of a fuel cylinder therein which is normally resiliently urged inwardly. The bellows contains a working fluid which undergoes a liquid to vapor phase change at a temperature substantially equal to the design temperature limit. Hence, the bellows abruptiy expands at this limiting temperature to force the fuel cylinder outward and render the core subcritical. The control device is particularly applicable to aircraft propulsion reactor service. (AEC)

  6. Looking Southwest at Reactor Box Furnaces With Reactor Boxes and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Southwest at Reactor Box Furnaces With Reactor Boxes and Repossessed Uranium in Recycle Recovery Building - Hematite Fuel Fabrication Facility, Recycle Recovery Building, 3300 State Road P, Festus, Jefferson County, MO

  7. NEUTRONIC REACTOR SYSTEM

    DOEpatents

    Daniels, F.

    1957-10-15

    Gas-cooled solid-moderator type reactors wherein the fissionable fuel and moderator materials are each in the form of solid pebbles, or discrete particles, and are substantially homogeneously mixed in the proper proportion and placed within the core of the reactor are described. The shape of these discrete particles must be such that voids are present between them when mixed together. Helium enters the bottom of the core and passes through the voids between the fuel and moderator particles to absorb the heat generated by the chain reaction. The hot helium gas is drawn off the top of the core and may be passed through a heat exchanger to produce steam.

  8. Plug Flow Reactor Simulator

    SciTech Connect

    Larson, Richard S.

    1996-07-30

    PLUG is a computer program that solves the coupled steady state continuity, momentum, energy, and species balance equations for a plug flow reactor. Both homogeneous (gas-phase) and heterogenous (surface) reactions can be accommodated. The reactor may be either isothermal or adiabatic or may have a specified axial temperature or heat flux profile; alternatively, an ambient temperature and an overall heat-transfer coefficient can be specified. The crosssectional area and surface area may vary with axial position, and viscous drag is included. Ideal gas behavior and surface site conservation are assumed.

  9. Fusion reactor pumped laser

    DOEpatents

    Jassby, Daniel L.

    1988-01-01

    A nuclear pumped laser capable of producing long pulses of very high power laser radiation is provided. A toroidal fusion reactor provides energetic neutrons which are slowed down by a moderator. The moderated neutrons are converted to energetic particles capable of pumping a lasing medium. The lasing medium is housed in an annular cell surrounding the reactor. The cell includes an annular reflecting mirror at the bottom and an annular output window at the top. A neutron reflector is disposed around the cell to reflect escaping neutrons back into the cell. The laser radiation from the annular window is focused onto a beam compactor which generates a single coherent output laser beam.

  10. Diagnostics for hybrid reactors

    NASA Astrophysics Data System (ADS)

    Orsitto, Francesco Paolo

    2012-06-01

    The Hybrid Reactor(HR) can be considered an attractive actinide-burner or a fusion assisted transmutation for destruction of transuranic(TRU) nuclear waste. The hybrid reactor has two important subsystems: the tokamak neutron source and the blanket which includes a fuel zone where the TRU are placed and a tritium breeding zone. The diagnostic system for a HR must be as simple and robust as possible to monitor and control the plasma scenario, guarantee the protection of the machine and monitor the transmutation.

  11. THERMAL NUCLEAR REACTOR

    DOEpatents

    Fenning, F.W.; Jackson, R.F.

    1957-09-24

    Nuclear reactors of the graphite moderated air cooled type in which canned slugs or rods of fissile material are employed are discussed. Such a reactor may be provided with a means for detecting dust particles in the exhausted air. The means employed are lengths of dust absorbent cord suspended in vertical holes in the shielding structure above each vertical coolant flow channel to hang in the path of the cooling air issuing from the channels, and associated spindles and drive motors for hauling the cords past detectors, such as Geiger counters, for inspecting the cords periodically. This design also enables detecting the individual channel in which a fault condition may have occurred.

  12. Particle bed reactor modeling

    NASA Technical Reports Server (NTRS)

    Sapyta, Joe; Reid, Hank; Walton, Lew

    1993-01-01

    The topics are presented in viewgraph form and include the following: particle bed reactor (PBR) core cross section; PBR bleed cycle; fuel and moderator flow paths; PBR modeling requirements; characteristics of PBR and nuclear thermal propulsion (NTP) modeling; challenges for PBR and NTP modeling; thermal hydraulic computer codes; capabilities for PBR/reactor application; thermal/hydralic codes; limitations; physical correlations; comparison of predicted friction factor and experimental data; frit pressure drop testing; cold frit mask factor; decay heat flow rate; startup transient simulation; and philosophy of systems modeling.

  13. Perspectives on reactor safety

    SciTech Connect

    Haskin, F.E.; Camp, A.L.

    1994-03-01

    The US Nuclear Regulatory Commission (NRC) maintains a technical training center at Chattanooga, Tennessee to provide appropriate training to both new and experienced NRC employees. This document describes a one-week course in reactor, safety concepts. The course consists of five modules: (1) historical perspective; (2) accident sequences; (3) accident progression in the reactor vessel; (4) containment characteristics and design bases; and (5) source terms and offsite consequences. The course text is accompanied by slides and videos during the actual presentation of the course.

  14. NEUTRONIC REACTOR CONTROL ELEMENT

    DOEpatents

    Newson, H.W.

    1960-09-13

    A novel composite neutronic reactor control element is offered. The element comprises a multiplicity of sections arranged in end-to-end relationship, each of the sections having a markedly different neutron-reactive characteristic. For example, a three-section control element could contain absorber, moderator, and fuel sections. By moving such an element longitudinally through a reactor core, reactivity is decreased by the absorber, increased slightly by the moderator, or increased substantially by the fuel. Thus, control over a wide reactivity range is provided.

  15. Plug Flow Reactor Simulator

    Energy Science and Technology Software Center (ESTSC)

    1996-07-30

    PLUG is a computer program that solves the coupled steady state continuity, momentum, energy, and species balance equations for a plug flow reactor. Both homogeneous (gas-phase) and heterogenous (surface) reactions can be accommodated. The reactor may be either isothermal or adiabatic or may have a specified axial temperature or heat flux profile; alternatively, an ambient temperature and an overall heat-transfer coefficient can be specified. The crosssectional area and surface area may vary with axial position,more » and viscous drag is included. Ideal gas behavior and surface site conservation are assumed.« less

  16. Fast quench reactor method

    SciTech Connect

    Detering, Brent A.; Donaldson, Alan D.; Fincke, James R.; Kong, Peter C.; Berry, Ray A.

    1999-01-01

    A fast quench reaction includes a reactor chamber having a high temperature heating means such as a plasma torch at its inlet and a means of rapidly expanding a reactant stream, such as a restrictive convergent-divergent nozzle at its outlet end. Metal halide reactants are injected into the reactor chamber. Reducing gas is added at different stages in the process to form a desired end product and prevent back reactions. The resulting heated gaseous stream is then rapidly cooled by expansion of the gaseous stream.

  17. Fast quench reactor method

    DOEpatents

    Detering, B.A.; Donaldson, A.D.; Fincke, J.R.; Kong, P.C.; Berry, R.A.

    1999-08-10

    A fast quench reaction includes a reactor chamber having a high temperature heating means such as a plasma torch at its inlet and a means of rapidly expanding a reactant stream, such as a restrictive convergent-divergent nozzle at its outlet end. Metal halide reactants are injected into the reactor chamber. Reducing gas is added at different stages in the process to form a desired end product and prevent back reactions. The resulting heated gaseous stream is then rapidly cooled by expansion of the gaseous stream. 8 figs.

  18. Diagnostics for hybrid reactors

    SciTech Connect

    Orsitto, Francesco Paolo

    2012-06-19

    The Hybrid Reactor(HR) can be considered an attractive actinide-burner or a fusion assisted transmutation for destruction of transuranic(TRU) nuclear waste. The hybrid reactor has two important subsystems: the tokamak neutron source and the blanket which includes a fuel zone where the TRU are placed and a tritium breeding zone. The diagnostic system for a HR must be as simple and robust as possible to monitor and control the plasma scenario, guarantee the protection of the machine and monitor the transmutation.

  19. MEANS FOR SHIELDING REACTORS

    DOEpatents

    Garrison, W.M.; McClinton, L.T.; Burton, M.

    1959-03-10

    A reactor of the heterageneous, heavy water moderated type is described. The reactor is comprised of a plurality of vertically disposed fuel element tubes extending through a tank of heavy water moderator and adapted to accommodate a flow of coolant water in contact with the fuel elements. A tank containing outgoing coolant water is disposed above the core to function is a radiation shield. Unsaturated liquid hydrocarbon is floated on top of the water in the shield tank to reduce to a minimum the possibility of the occurrence of explosive gaseous mixtures resulting from the neutron bombardment of the water in the shield tank.

  20. Breeder reactors in France

    SciTech Connect

    Zaleski, C.P.

    1980-04-11

    France relies on nuclear power as an important part of her energy program. Anticipating problems with the availability of natural uranium before the year 2020, the French have been pursuing a three-stage program of development of breeder reactors. The third reactor in this program, the near-commercial plant Super Phenix Mark I, is expected to reach power operation in 1983. Although there are still some uncertainties, particularly about the date when the breeder will become competitive with other energy sources, the outlook is considered favorable and preliminary designs for commercial plants are under way.

  1. One utility`s approach to radwaste

    SciTech Connect

    O`Brian, G.

    1995-11-01

    Recently, the Northern States Power Company (NSP) has taken a {open_quotes}very active{close_quotes} role in the High-Level Waste (HLW) issue. This decision was not an easy one for NSP which has traditionally been satisfied with remaining silent politically and active technically. However, all of the excellent technical efforts could go for naught based on a single political decision. In as much as the HLW and Low-Level Waste (LLW) issues are being decided in the political arena, I believe the industry can learn from our experience with the HLW issue. Therefore, I will explain the scenario of events and NSP`s reactions surrounding dry cask storage at NSP`s Prairie Island Nuclear Generating Plant, and how these reactions have helped us deal with the LLW issue. During the Plant Life EXtension (PLEX) project at the Monticello Nuclear Generating Plant, four critical issues were identified as requiring resolution prior to NSP committing additional resources toward the PLEX project. The HLW and LLW issues were among the list. Although the importance of the two issues had been realized prior to 1990, NSP did not make any appreciable changes to address either of these issues until an amendment was made in the 1992 Minnesota legislative session which would have removed the decision to approve the Prairie Island dry cask storage project from the jurisdiction of the Public Utilities Commission (PUC) and shifted it to the state legislature. Several plant employees met at the state capitol throughout the week to lobby against the amendment. Ultimately, the amendment was debated on the Senate floor and failed.

  2. Fly ash quality and utilization

    SciTech Connect

    Barta, L.E.; Lachner, L.; Wenzel, G.B.; Beer, M.J.

    1995-12-01

    The quality of fly ash is of considerable importance to fly ash utilizers. The fly ash puzzolanic activity is one of the most important properties that determines the role of fly ash as a binding agent in the cementing process. The puzzolanic activity, however is a function of fly ash particle size and chemical composition. These parameters are closely related to the process of fly ash formation in pulverized coal fired furnaces. In turn, it is essential to understand the transformation of mineral matter during coal combustion. Due to the particle-to-particle variation of coal properties and the random coalescence of mineral particles, the properties of fly ash particles e.g. size, SiO{sub 2} content, viscosity can change considerably from particle to particle. These variations can be described by the use of the probability theory. Since the mean values of these randomly changing parameters are not sufficient to describe the behavior of individual fly ash particles during the formation of concrete, therefore it is necessary to investigate the distribution of these variables. Examples of these variations were examined by the Computer Controlled Scanning Electron Microscopy (CCSEM) for particle size and chemical composition for Texas lignite and Eagel Butte mineral matter and fly ash. The effect of combustion on the variations of these properties for both the fly ash and mineral matter were studied by using a laminar flow reactor. It is shown in our paper, that there are significant variations (about 40-50% around the mean values) of the above-listed properties for both coal samples. By comparing the particle size and chemical composition distributions of the mineral matter and fly ash, it was possible to conclude that for the Texas lignite mineral matter, the combustion did not effect significantly the distribution of these properties, however, for the Eagel Butte coal the combustion had a major impact on these mineral matter parameters.

  3. Knowledge Production and Utilization.

    ERIC Educational Resources Information Center

    Beal, George M.; Meehan, Peter

    The study of knowledge production and utilization deals with the problems of how to translate theoretical concepts and knowledge into practical solutions to people's problems. Many criticisms have been leveled at aspects of previous information system models, including their linearity, one-way communication paths, overdependence on scientific…

  4. Male Adolescent Contraceptive Utilization.

    ERIC Educational Resources Information Center

    Finkel, Madelon Lubin; Finkel, David J.

    1978-01-01

    The contraceptive utilization of a sample of sexually active, urban, high school males (Black, Hispanic, and White) was examined by anonymous questionnaire. Contraceptive use was haphazard, but White males tended to be more effective contraceptors than the other two groups. Reasons for nonuse were also studied. (Author/SJL)

  5. NASA technology utilization house

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Following systems and features, which are predicted to save approximately $20,000 in utility costs over twenty year period, are incorporated into single-level, contemporarily designed, energy efficient residential structure: solar heating and cooling; energy efficient appliances; water recycling; security, smoke, and tornado detectors; and flat conductor electrical wiring.

  6. Module utilization committee

    NASA Technical Reports Server (NTRS)

    Volkmer, K.; Praver, G.

    1984-01-01

    Photovoltaic collector modules were declared surplus to the needs of the U.S. Dept. of Energy. The Module Utilization Committee was formed to make appropriate disposition of the surplus modules on a national basis and to act as a broker for requests for these modules originating outside of the National Photovoltaics Program.

  7. Utilities. [univac computer programs

    NASA Technical Reports Server (NTRS)

    Colquitt, W. N.

    1976-01-01

    Several sets of related Adage utility programs are described. A general description of the software group, instructions on how to use the programs, and a programmers description of the theory of operation are given along with a printed example of the program in use and a listing of the program.

  8. Technology utilization program report

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The application of aerospace technology to the solution of public health and industrial problems is reported. Data cover: (1) development of an externally rechargeable cardiac pacemaker, (2) utilization of ferrofluids-colloidal suspensions of ferrite particles - in the efficient separation of nonferrous metals as Ni, Zn, Cu, and Al from shredded automobile scrap, and (3) development of a breathing system for fire fighters.

  9. Classroom Use and Utilization.

    ERIC Educational Resources Information Center

    Fink, Ira

    2002-01-01

    Discusses how classrooms are distributed by size on a campus, how well they are used, and how their use changes with faculty and student needs and desires. Details how to analyze classroom space, use, and utilization, taking into account such factors as scheduling and classroom stations. (EV)

  10. A Classroom Mathematics Utility.

    ERIC Educational Resources Information Center

    Williams, Michael

    1984-01-01

    Reviews CATUSPLOT, a mathematics utility aimed at high school algebra through college-level calculus. Basic program capabilities include plotting, tabulating, integrating, and locating of intersections of functions composed of combinations of polynomial, trigonometric, and exponential functions. Rated excellent on all areas examined…

  11. Administrative Utility Analysis: Appendices.

    ERIC Educational Resources Information Center

    Peat, Marwick, Mitchell and Co., San Juan, Puerto Rico.

    Appendixes to a study on administrative utility analysis and vocational education programs for the Area of Vocational and Technical Education (AVTE) in the Puerto Rico Department of Education contain the planning and budgeting system elements, position descriptions, and information on the growth of vocational education in Puerto Rico. The elements…

  12. Utilizing Foundational Perspectives.

    ERIC Educational Resources Information Center

    Educational Foundations, 1991

    1991-01-01

    This theme issue of "Educational Foundations" contains five articles that utilize an array of foundational perspectives that give reader insight into the organization of schools, the viewpoints of children and parents, the ideological and political nature of community organizing, and mathematics instruction in the Soviet Union. In "Cooperative…

  13. Transport in a Microfluidic Catalytic Reactor

    SciTech Connect

    Park, H G; Chung, J; Grigoropoulos, C P; Greif, R; Havstad, M; Morse, J D

    2003-04-30

    A study of the heat and mass transfer, flow, and thermodynamics of the reacting flow in a catalytic microreactor is presented. Methanol reforming is utilized in the fuel processing system driving a micro-scale proton exchange membrane fuel cell. Understanding the flow and thermal transport phenomena as well as the reaction mechanisms is essential for improving the efficiency of the reforming process as well as the quality of the processed fuel. Numerical studies have been carried out to characterize the transport in a silicon microfabricated reactor system. On the basis of these results, optimized conditions for fuel processing are determined.

  14. The Neutron Radiography Reactor (NRAD)

    SciTech Connect

    Imel, G.R.; McClellan, G.C.; Pruett, D.P.

    1990-01-01

    The Neutron Radiography Reactor (NRAD) operated by Argonne National Laboratory is described in this paper. NRAD was designed to allow radiography of highly absorbing reactor fuel assemblies in the vertical position on the routine basis. 7 figs.

  15. Reactor operation environmental information document

    SciTech Connect

    Haselow, J.S.; Price, V.; Stephenson, D.E.; Bledsoe, H.W.; Looney, B.B.

    1989-12-01

    The Savannah River Site (SRS) produces nuclear materials, primarily plutonium and tritium, to meet the requirements of the Department of Defense. These products have been formed in nuclear reactors that were built during 1950--1955 at the SRS. K, L, and P reactors are three of five reactors that have been used in the past to produce the nuclear materials. All three of these reactors discontinued operation in 1988. Currently, intense efforts are being extended to prepare these three reactors for restart in a manner that protects human health and the environment. To document that restarting the reactors will have minimal impacts to human health and the environment, a three-volume Reactor Operations Environmental Impact Document has been prepared. The document focuses on the impacts of restarting the K, L, and P reactors on both the SRS and surrounding areas. This volume discusses the geology, seismology, and subsurface hydrology. 195 refs., 101 figs., 16 tabs.

  16. Determination of the Sensitivity of the Antineutrino Probe for Reactor Core Monitoring

    SciTech Connect

    Cormon, S.; Fallot, M. Bui, V.-M.; Cucoanes, A.; Estienne, M.; Lenoir, M.; Onillon, A.; Shiba, T.; Yermia, F.; Zakari-Issoufou, A.-A.

    2014-06-15

    This paper presents a feasibility study of the use of the detection of reactor-antineutrinos (ν{sup ¯}{sub e}) for non proliferation purpose. To proceed, we have started to study different reactor designs with our simulation tools. We use a package called MCNP Utility for Reactor Evolution (MURE), initially developed by CNRS/IN2P3 labs to study Generation IV reactors. The MURE package has been coupled to fission product beta decay nuclear databases for studying reactor antineutrino emission. This method is the only one able to predict the antineutrino emission from future reactor cores, which don't use the thermal fission of {sup 235}U, {sup 239}Pu and {sup 241}Pu. It is also the only way to include off-equilibrium effects, due to neutron captures and time evolution of the fission product concentrations during a reactor cycle. We will present here the first predictions of antineutrino energy spectra from innovative reactor designs (Generation IV reactors). We will then discuss a summary of our results of non-proliferation scenarios involving the latter reactor designs, taking into account reactor physics constraints.

  17. Irradiation performance of (Th,Pu)O2 fuel under Pressurized Water Reactor conditions

    NASA Astrophysics Data System (ADS)

    Boer, B.; Lemehov, S.; Wéber, M.; Parthoens, Y.; Gysemans, M.; McGinley, J.; Somers, J.; Verwerft, M.

    2016-04-01

    This paper examines the in-pile safety performance of (Th,Pu)O2 fuel pins under simulated Pressurized Water Reactor (PWR) conditions. Both sol-gel and SOLMAS produced (Th,Pu)O2 fuels at enrichments of 7.9% and 12.8% in Pu/HM have been irradiated at SCK·CEN. The irradiation has been performed under PWR conditions (155 bar, 300 °C) in a dedicated loop of the BR-2 reactor. The loop is instrumented with flow and temperature monitors at inlet and outlet, which allow for an accurate measurement of the deposited enthalpy. Between 2004 and 2006, four fuel segments were irradiated, with on-line recording of centerline temperature and rod pressure of the two instrumented rods and intermittent non-destructive hot-cell investigations of the other two non-instrumented rods. At the end of 2006, the instrumented rods were unloaded for hot-cell investigations. The hot-cell investigations reduced uncertainties in the power history to build a reliable and consistent irradiation history which can be used to assess and validate fuel performance codes. The on-line recorded temperatures of the instrumented rods are presented in this paper and are compared to corresponding calculations on the basis of the power history. One of the non-instrumented rods was re-inserted in the reactor in 2012 and attained a peak burnup level of 37 GWd/tHM by the end of 2014. The combined data set of on-line measurements and post irradiation examinations enables further code validation. In this context, the results of the in-house MACROS code of SCK·CEN have been compared with the experimental results. The code contains dedicated (Th,Pu)O2 models for the calculation of the thermal conductivity as a function of the burnup and models that determine the radial power profile within the pellet.

  18. Reactor operation safety information document

    SciTech Connect

    Not Available

    1990-01-01

    The report contains a reactor facility description which includes K, P, and L reactor sites, structures, operating systems, engineered safety systems, support systems, and process and effluent monitoring systems; an accident analysis section which includes cooling system anomalies, radioactive materials releases, and anticipated transients without scram; a summary of onsite doses from design basis accidents; severe accident analysis (reactor core disruption); a description of operating contractor organization and emergency planning; and a summary of reactor safety evolution. (MB)

  19. Reactor cell assembly for use in spectroscopy and microscopy applications

    SciTech Connect

    Grindstaff, Quirinus; Stowe, Ashley Clinton; Smyrl, Norm; Powell, Louis; McLane, Sam

    2015-08-04

    The present disclosure provides a reactor cell assembly that utilizes a novel design and that is wholly or partially manufactured from Aluminum, such that reactions involving Hydrogen, for example, including solid-gas reactions and thermal decomposition reactions, are not affected by any degree of Hydrogen outgassing. This reactor cell assembly can be utilized in a wide range of optical and laser spectroscopy applications, as well as optical microscopy applications, including high-temperature and high-pressure applications. The result is that the elucidation of the role of Hydrogen in the reactions studied can be achieved. Various window assemblies can be utilized, such that high temperatures and high pressures can be accommodated and the signals obtained can be optimized.

  20. Neutronic reactor thermal shield

    DOEpatents

    Wende, Charles W. J.

    1976-06-15

    1. The method of operating a water-cooled neutronic reactor having a graphite moderator which comprises flowing a gaseous mixture of carbon dioxide and helium, in which the helium comprises 40-60 volume percent of the mixture, in contact with the graphite moderator.