A neutron poison tritium breeding controller applied to a water cooled fusion reactor model

International Nuclear Information System (INIS)

Morgan, L.W.G.; Packer, L.W.

2014-01-01

Highlights: • The issue of a potentially producing a large tritium surplus inventory, within a solid breeder, is addressed. • A possible solution to this problem is presented in the form of a neutron poison based tritium production controller. • The tritium surplus inventory has been modelled by the FATI code for a simplified WCCB model and as a function of time. • It has been demonstrated that the tritium surplus inventory can be managed, which may impact on safety considerations. - Abstract: The generation of tritium in sufficient quantities is an absolute requirement for a next step fusion device such as DEMO due to the scarcity of tritium sources. Although the production of sufficient quantities of tritium will be one of the main challenges for DEMO, within an energy economy featuring several fusion power plants the active control of tritium production may be required in order to manage surplus tritium inventories at power plant sites. The primary reason for controlling the tritium inventory in such an economy would therefore be to minimise the risk and storage costs associated with large quantities of surplus tritium. In order to ensure that enough tritium will be produced in a reactor which contains a solid tritium breeder, over the reactor's lifetime, the tritium breeding rate at the beginning of its lifetime is relatively high and reduces over time. This causes a large surplus tritium inventory to build up until approximately halfway through the lifetime of the blanket, when the inventory begins to decrease. This surplus tritium inventory could exceed several tens of kilograms of tritium, impacting on possible safety and licensing conditions that may exist. This paper describes a possible solution to the surplus tritium inventory problem that involves neutron poison injection into the coolant, which is managed with a tritium breeding controller. A simple PID controller and is used to manage the injection of the neutron absorbing compounds into

A neutron poison tritium breeding controller applied to a water cooled fusion reactor model

Energy Technology Data Exchange (ETDEWEB)

Morgan, L.W.G., E-mail: Lee.Morgan@CCFE.ac.uk; Packer, L.W.

2014-10-15

Highlights: • The issue of a potentially producing a large tritium surplus inventory, within a solid breeder, is addressed. • A possible solution to this problem is presented in the form of a neutron poison based tritium production controller. • The tritium surplus inventory has been modelled by the FATI code for a simplified WCCB model and as a function of time. • It has been demonstrated that the tritium surplus inventory can be managed, which may impact on safety considerations. - Abstract: The generation of tritium in sufficient quantities is an absolute requirement for a next step fusion device such as DEMO due to the scarcity of tritium sources. Although the production of sufficient quantities of tritium will be one of the main challenges for DEMO, within an energy economy featuring several fusion power plants the active control of tritium production may be required in order to manage surplus tritium inventories at power plant sites. The primary reason for controlling the tritium inventory in such an economy would therefore be to minimise the risk and storage costs associated with large quantities of surplus tritium. In order to ensure that enough tritium will be produced in a reactor which contains a solid tritium breeder, over the reactor's lifetime, the tritium breeding rate at the beginning of its lifetime is relatively high and reduces over time. This causes a large surplus tritium inventory to build up until approximately halfway through the lifetime of the blanket, when the inventory begins to decrease. This surplus tritium inventory could exceed several tens of kilograms of tritium, impacting on possible safety and licensing conditions that may exist. This paper describes a possible solution to the surplus tritium inventory problem that involves neutron poison injection into the coolant, which is managed with a tritium breeding controller. A simple PID controller and is used to manage the injection of the neutron absorbing compounds into

Reactivity and neutron flux measurements in IPEN/MB-01 reactor with B4C burnable poison

International Nuclear Information System (INIS)

Fer, Nelson Custodio; Moreira, Joao Manoel Losada

2000-01-01

Burnable poison rods, made of B 4 C- Al 2 O 3 pellets with 5.01 mg/cm 3 10 B concentration, have been manufactured for a set of experiments in the IPEN/MB-01 zero-power reactor. Several core parameters which are affected by the burnable poisons rods have been measured. The principal results, for the situation in which the burnable poison rods are located near the absorber rods of a control rod, are they cause a 29% rod worth shadowing, a reduction of 39% in the local void coefficient of reactivity, a reduction of 4.8% in the isothermal temperature coefficient of reactivity, and a reduction of 9% in the thermal neutron flux in the region where the burnable poison rods are located. These experimental results will be used for the validation of burnable poison calculation methods in the CTMSP. (author)

A new fast neutron collar for safeguards inspection measurements of fresh low enriched uranium fuel assemblies containing burnable poison rods

Energy Technology Data Exchange (ETDEWEB)

Evans, Louise G., E-mail: evanslg@ornl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Swinhoe, Martyn T.; Menlove, Howard O. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Schwalbach, Peter; Baere, Paul De [European Commission, Euratom Safeguards Office (Luxembourg); Browne, Michael C. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2013-11-21

Safeguards inspection measurements must be performed in a timely manner in order to detect the diversion of significant quantities of nuclear material. A shorter measurement time can increase the number of items that a nuclear safeguards inspector can reliably measure during a period of access to a nuclear facility. In turn, this improves the reliability of the acquired statistical sample, which is used to inform decisions regarding compliance. Safeguards inspection measurements should also maintain independence from facility operator declarations. Existing neutron collars employ thermal neutron interrogation for safeguards inspection measurements of fresh fuel assemblies. A new fast neutron collar has been developed for safeguards inspection measurements of fresh low-enriched uranium (LEU) fuel assemblies containing gadolinia (Gd{sub 2}O{sub 3}) burnable poison rods. The Euratom Fast Collar (EFC) was designed with high neutron detection efficiency to make a fast (Cd) mode measurement viable whilst meeting the high counting precision and short assay time requirements of the Euratom safeguards inspectorate. A fast mode measurement reduces the instrument sensitivity to burnable poison rod content and therefore reduces the applied poison correction, consequently reducing the dependence on the operator declaration of the poison content within an assembly. The EFC non-destructive assay (NDA) of typical modern European pressurized water reactor (PWR) fresh fuel assembly designs have been simulated using Monte Carlo N-particle extended transport code (MCNPX) simulations. Simulations predict that the EFC can achieve 2% relative statistical uncertainty on the doubles neutron counting rate for a fast mode measurement in an assay time of 600 s (10 min) with the available {sup 241}AmLi (α,n) interrogation source strength of 5.7×10{sup 4} s{sup −1}. Furthermore, the calibration range of the new collar has been extended to verify {sup 235}U content in variable PWR fuel

A new fast neutron collar for safeguards inspection measurements of fresh low enriched uranium fuel assemblies containing burnable poison rods

International Nuclear Information System (INIS)

Evans, Louise G.; Swinhoe, Martyn T.; Menlove, Howard O.; Schwalbach, Peter; Baere, Paul De; Browne, Michael C.

2013-01-01

Safeguards inspection measurements must be performed in a timely manner in order to detect the diversion of significant quantities of nuclear material. A shorter measurement time can increase the number of items that a nuclear safeguards inspector can reliably measure during a period of access to a nuclear facility. In turn, this improves the reliability of the acquired statistical sample, which is used to inform decisions regarding compliance. Safeguards inspection measurements should also maintain independence from facility operator declarations. Existing neutron collars employ thermal neutron interrogation for safeguards inspection measurements of fresh fuel assemblies. A new fast neutron collar has been developed for safeguards inspection measurements of fresh low-enriched uranium (LEU) fuel assemblies containing gadolinia (Gd 2 O 3 ) burnable poison rods. The Euratom Fast Collar (EFC) was designed with high neutron detection efficiency to make a fast (Cd) mode measurement viable whilst meeting the high counting precision and short assay time requirements of the Euratom safeguards inspectorate. A fast mode measurement reduces the instrument sensitivity to burnable poison rod content and therefore reduces the applied poison correction, consequently reducing the dependence on the operator declaration of the poison content within an assembly. The EFC non-destructive assay (NDA) of typical modern European pressurized water reactor (PWR) fresh fuel assembly designs have been simulated using Monte Carlo N-particle extended transport code (MCNPX) simulations. Simulations predict that the EFC can achieve 2% relative statistical uncertainty on the doubles neutron counting rate for a fast mode measurement in an assay time of 600 s (10 min) with the available 241 AmLi (α,n) interrogation source strength of 5.7×10 4 s −1 . Furthermore, the calibration range of the new collar has been extended to verify 235 U content in variable PWR fuel designs in the presence of up to

Calculation of depletion with optimal distribution of initial control poison

International Nuclear Information System (INIS)

Castro Lobo, P.D. de.

1978-03-01

The spatial depletion equations are linearized within the time intervals and their solution is obtained by modal analysis. At the beginning of life an optimal poison distribution that maximizes neutron economy and the corresponding flux is determined. At the start of the subsequent time steps the flux distributions are obtained by pertubation method in relation to the start of the previous time steps. The problem was studied with constant poison distribution in order to evaluate the influence of the poison at the beginning of life. The results obtained by the modal expansion techniques are satisfactory. However, the optimization of the initial distribution of the control poison does not indicate any significant effect on the core life [pt

In-core LOCA-s: analytical solution for the delayed mixing model for moderator poison concentration

International Nuclear Information System (INIS)

Firla, A.P.

1995-01-01

Solutions to dynamic moderator poison concentration model with delayed mixing under single pressure tube / calandria tube rupture scenario are discussed. Such a model is described by a delay differential equation, and for such equations the standard ways of solution are not directly applicable. In the paper an exact, direct time-domain analytical solution to the delayed mixing model is presented and discussed. The obtained solution has a 'marching' form and is easy to calculate numerically. Results of the numerical calculations based on the analytical solution indicate that for the expected range of mixing times the existing uniform mixing model is a good representation of the moderator poison mixing process for single PT/CT breaks. However, for postulated multi-pipe breaks ( which is very unlikely to occur ) the uniform mixing model is not adequate any more; at the same time an 'approximate' solution based on Laplace transform significantly overpredicts the rate of poison concentration decrease, resulting in excessive increase in the moderator dilution factor. In this situation the true, analytical solution must be used. The analytical solution presented in the paper may also serve as a bench-mark test for the accuracy of the existing poison mixing models. Moreover, because of the existing oscillatory tendency of the solution, special care must be taken in using delay differential models in other applications. (author). 3 refs., 3 tabs., 8 figs

Evaluation of neutronic characteristics of STACY 80-cm-diameter cylindrical core fueled with 6% enriched uranyl nitrate solution

International Nuclear Information System (INIS)

Yanagisawa, Hiroshi; Sono, Hiroki

2003-06-01

For the examination of neutronic safety design of forthcoming experimental core configurations in the Static Experiment Critical Facility (STACY), neutronic characteristics of 80-cm-diameter cylindrical cores fueled with 6% enriched uranyl nitrate solution have been evaluated by computational analyses. In the analyses, the latest nuclear data library, JENDL-3.3, was used as neutron cross section data. The neutron diffusion and transport calculations were performed using a diffusion code, CITATION, in the SRAC code system and a continuous-energy Monte Carlo code, MVP. Critical level heights of the cores were obtained using such parameters as uranium concentration (up to 500 gU/l), free nitric acid concentration (up to 8 mol/l), and concentration of soluble neutron poisons, gadolinium and boron. It has been confirmed from the evaluation that all critical cores comply with safety criteria required in the STACY operation concerning excess reactivity, reactivity addition rates and shutdown margins by safety rods. (author)

Neutron physical investigations on the use of burnable poisons and gray absorber rods in large pressurized water reactors

International Nuclear Information System (INIS)

Brosche, C.; Katinger, T.; Kollmar, W.; Thieme, K.; Wagner, M.R.

1977-11-01

Methods and results of neutron physics calculations are described using burnable poisons and gray absorber rods in large PWR's. Calculated and measured values are compared, the effort for programming has been guessed. (orig.) [de

Intrinsic neutron source strengths in uranium solutions

International Nuclear Information System (INIS)

Anderson, R.E.; Robba, A.A.; Seale, R.L.; Rutherford, D.A.; Butterfield, K.B.; Brunson, G.S.

1991-01-01

Neutron production rates for 5% enriched uranyl fluoride and 93% uranyl nitrate solutions have been measured using a high-efficiency neutron well counter. Measurements were made for both solution types as a function of sample volume. These results were extrapolated to zero sample volume to eliminate sample size effects, such as multiplication and absorption. For the 5% enriched uranyl fluoride solution, a neutron production rate of 0.0414 ± 0.0041 n/s/ml was measured; for the 93% enriched uranyl nitrate solution, a neutron production rate of 0.0232 ± 0.0023 n/s/ml was measured. The biggest uncertainty is in measuring the detector efficiency, and further work on this aspect of the experiment is planned. Calculations for the neutron production rates based on measured thick-target (alpha, n) production rates and shown alpha stopping powers are in reasonable agreement with the data for the uranyl nitrate solution, but are in poor agreement with the data for the uranyl fluoride solution. 8 refs., 7 figs., 5 tabs

Low reactivity penalty burnable poison rods

International Nuclear Information System (INIS)

1978-01-01

A nuclear reactor burnable poison rod is described which consists of an elongated tubular sheath enclosing a neutron absorbing material which, at least during reactor operation, also encloses a neutron moderating material. The excess reactivity existing at the beginning of core life is compensated for by the depletion of the burnable poison throughout the life of the core, so that the life of the core is extended. (UK)

Measurement of the Decay of Thermal Neutrons in Water Poisoned with the Non-1/v Neutron Absorber Cadmium

Energy Technology Data Exchange (ETDEWEB)

Larsson, L G; Moeller, E

1968-01-15

Measurements have been made of the decay constant of thermal neutrons in water poisoned with the non-1/v absorber cadmium. An experimental method has been used in which proper spatial integration of the neutron flux enables data, representative of the infinite medium to be accumulated without waiting for the establishment of a fundamental mode distribution. The change in effective cross section with concentration of the dissolved cadmium, d{sigma}{sub eff}/dN. has been determined for infinite medium at 20 deg C. Two- and three parameter fits of the decay constant yield -(0.32 {+-} 0.09) x 10{sup -17} barn cm{sup 3} and -(0.47 {+-} 0.10) x 10{sup -17} barn cm{sup 3}, respectively. Earlier published measurements have resulted in two to five times larger values, whereas a published calculated value of Nelkin's model is - 0.33 x 10{sup -17} barn cm{sup 3}.

Measurement of the Decay of Thermal Neutrons in Water Poisoned with the Non-1/v Neutron Absorber Cadmium

International Nuclear Information System (INIS)

Larsson, L.G.; Moeller, E.

1968-01-01

Measurements have been made of the decay constant of thermal neutrons in water poisoned with the non-1/v absorber cadmium. An experimental method has been used in which proper spatial integration of the neutron flux enables data, representative of the infinite medium to be accumulated without waiting for the establishment of a fundamental mode distribution. The change in effective cross section with concentration of the dissolved cadmium, dσ eff /dN. has been determined for infinite medium at 20 deg C. Two- and three parameter fits of the decay constant yield -(0.32 ± 0.09) x 10 -17 barn cm 3 and -(0.47 ± 0.10) x 10 -17 barn cm 3 , respectively. Earlier published measurements have resulted in two to five times larger values, whereas a published calculated value of Nelkin's model is - 0.33 x 10 -17 barn cm 3

Determination of mercury in human tissues after acute poisoning by neutron activation

International Nuclear Information System (INIS)

Rakovic, M.; Glagolicova, A.; Prouza, Z.; Gregora, Z.

1976-01-01

The non-destructive determination of mercury in human tissues after acute poisoning based on the use of a γ-ray spectometer with a Ge(Li) semiconductor detector is described. Samples were irradiated at a thermal neutron flux density of about 10 12 n cm -2 s -1 for 4 hrs. From the results of the preliminary experiments the following conclusions have been drawn. The mercury losses should be negligible when drying of the biological samples at 80 deg C. To irradiate samples for mercury determination is preferable in silica tubes than in polyethylene ones. (T.I.)

Determination of As by instrumental neutron activation analysis in sectioned hair samples for forensic purposes: chronic or acute poisoning?

Czech Academy of Sciences Publication Activity Database

Kučera, Jan; Kofronova, K.

2011-01-01

Roč. 287, č. 3 (2011), s. 769-772 ISSN 0236-5731 Institutional research plan: CEZ:AV0Z10480505 Keywords : Instrumental neutron activation analysis * Hair * Arsenic poisoning Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.520, year: 2011

Exact solution of the neutron transport equation in spherical geometry

Energy Technology Data Exchange (ETDEWEB)

Anli, Fikret; Akkurt, Abdullah; Yildirim, Hueseyin; Ates, Kemal [Kahramanmaras Suetcue Imam Univ. (Turkey). Faculty of Sciences and Letters

2017-03-15

Solution of the neutron transport equation in one dimensional slab geometry construct a basis for the solution of neutron transport equation in a curvilinear geometry. Therefore, in this work, we attempt to derive an exact analytical benchmark solution for both neutron transport equations in slab and spherical medium by using P{sub N} approximation which is widely used in neutron transport theory.

Moderator poison design and burn-up calculations at the SNS

International Nuclear Information System (INIS)

Lu, W.; Ferguson, P.D.; Iverson, E.B.; Gallmeier, F.X.; Popova, I.

2008-01-01

The spallation neutron source (SNS) at Oak Ridge National Laboratory was commissioned in April 2006. At the nominal operating power (1.4 MW), it will have thermal neutron fluxes approximately an order of magnitude greater than any existing pulsed spallation source. It thus brings a serious challenge to the lifetime of the moderator poison sheets. The SNS moderators are integrated with the inner reflector plug (IRP) at a cost of ∼$2 million a piece. A replacement of the inner reflector plug presents a significant drawback to the facility due to the activation and the operation cost. Although there are a lot of factors limiting the lifetime of the inner reflector plug, like radiation damage to the structural material and helium production of beryllium, the bottle-neck is the lifetime of the moderator poison sheets. Increasing the thickness of the poison sheet extends the lifetime but would sacrifice the neutronic performance of the moderators. A compromise is accepted at the current SNS target system which uses thick Gd poison sheets at a projected lifetime of 6 MW-years of operation. The calculations in this paper reveal that Cd may be a better poison material from the perspective of lifetime and neutronic performance. In replacing Gd, the inner reflector plug could reach a lifetime of 8 MW-years with ∼5% higher peak neutron fluxes at almost no loss of energy resolution

Adjoint P1 equations solution for neutron slowing down

International Nuclear Information System (INIS)

Cardoso, Carlos Eduardo Santos; Martinez, Aquilino Senra; Silva, Fernando Carvalho da

2002-01-01

In some applications of perturbation theory, it is necessary know the adjoint neutron flux, which is obtained by the solution of adjoint neutron diffusion equation. However, the multigroup constants used for this are weighted in only the direct neutron flux, from the solution of direct P1 equations. In this work, the adjoint P1 equations are derived by the neutron transport equation, the reversion operators rules and analogies between direct and adjoint parameters. The direct and adjoint neutron fluxes resulting from the solution of P 1 equations were used to three different weighting processes, to obtain the macrogroup macroscopic cross sections. It was found out noticeable differences among them. (author)

Potential use of hyperoxygenated solution as a treatment strategy for carbon monoxide poisoning.

Directory of Open Access Journals (Sweden)

Xingxing Sun

Full Text Available AIM: Carbon monoxide (CO poisoning can cause permanent damage in tissues that are sensitive to hypoxia. We explored the feasibility and efficacy of using a hyperoxygenated solution (HOS to treat severe acute CO poisoning in an animal model. METHODS: Male Sprague-Dawley rats were subjected to CO poisoning. The HOS was administered into the femoral vein of these rats through a catheter (10 ml/kg. Carboxyhemoglobin (COHb and blood gases were used to assess the early damage caused by CO poisoning. S100β was measured to predict the development of late cognitive sequelae of CO. The Morris water maze test was performed to assess cognitive function, and Nissl staining was performed to observe histologic change. RESULTS: The COHb concentrations rapidly decreased at 5 min after the HOS administration; however, the PaO2 and SaO2 in rats treated with HOS increased significantly 5 min after the HOS administration. The S100β concentrations, which increased significantly after CO poisoning, increased at a much slower rate in the rats treated with HOS (HOS group compared with the rats treated with O2 inhalation (O2 group. The escape latency in the place navigation test was shortened after CO poisoning on days 11-15 and days 26-30, and the swimming time in quadrant 4 in the spatial probe test on days 15 and 30 after CO poisoning was prolonged in the rats treated with HOS injection compared with the rats treated with oxygen inhalation or normal saline injection. The neuronal degeneration in the HOS group was alleviated than that in the CO or O2 group. CONCLUSION: HOS efficiently alleviates the brain damage in acute CO-poisoned rats and thus may serve as a new way to treat human patients with CO poisoning in clinical practice.

Approximate solution for the reactor neutron probability distribution

International Nuclear Information System (INIS)

Ruby, L.; McSwine, T.L.

1985-01-01

Several authors have studied the Kolmogorov equation for a fission-driven chain-reacting system, written in terms of the generating function G(x,y,z,t) where x, y, and z are dummy variables referring to the neutron, delayed neutron precursor, and detector-count populations, n, m, and c, respectively. Pal and Zolotukhin and Mogil'ner have shown that if delayed neutrons are neglected, the solution is approximately negative binomial for the neutron population. Wang and Ruby have shown that if the detector effect is neglected, the solution, including the effect of delayed neutrons, is approximately negative binomial. All of the authors assumed prompt-neutron emission not exceeding two neutrons per fission. An approximate method of separating the detector effect from the statistics of the neutron and precursor populations has been proposed by Ruby. In this weak-coupling limit, it is assumed that G(x,y,z,t) = H(x,y)I(z,t). Substitution of this assumption into the Kolmogorov equation separates the latter into two equations, one for H(x,y) and the other for I(z,t). Solution of the latter then gives a generating function, which indicates that in the weak-coupling limit, the detector counts are Poisson distributed. Ruby also showed that if the detector effect is neglected in the equation for H(x,y), i.e., the detector efficiency is set to zero, then the resulting equation is identical with that considered by Wang and Ruby. The authors present here an approximate solution for H(x,y) that does not set the detector efficiency to zero

RPV housed ATWS poison tank

International Nuclear Information System (INIS)

Oosterkamp, W.J.

1992-01-01

This patent describes a boiling water reactor (BWR) wherein housed within a reactor pressure vessel (RPV) is a nuclear core and an upper steam dome connected to a steam outlet in the RPV. The improvement comprises: a pressurized vessel disposed in the steam dome containing a neutron poison effective for inactivating the core and a first line for assaying the poison which first line runs to the outside of the RPV, the vessel being vented to the steam dome to pressurize the poison contained therein, the vessel being connected by a second line terminating beneath the core, the second line containing a valve which is actuable to release the poison through the line upon its actuation

Neutron scattering study of dilute supercritical solutions

International Nuclear Information System (INIS)

Cochran, H.D.; Wignall, G.D.; Shah, V.M.; Londono, J.D.; Bienkowski, P.R.

1994-01-01

Dilute solutions in supercritical solvents exhibit interesting microstructures that are related to their dramatic macroscopic behavior. In typical attractive solutions, solutes are believed to be surrounded by clusters of solvent molecules, and solute molecules are believed to congregate in the vicinity of one another. Repulsive solutions, on the other hand, exhibit a local region of reduced solvent density around the solute with solute-solute congregation. Such microstructures influence solubility, partial molar volume, reaction kinetics, and many other properties. We have undertaken to observe these interesting microstructures directly by neutron scattering experiments on dilute noble gas systems including Ar. The three partial structure factors for such systems and the corresponding pair correlation functions can be determined by using the isotope substitution technique. The systems studied are uniquely suited for our objectives because of the large coherent neutron scattering length of the isotope 36 Ar and because of the accurate potential energy functions that are available for use in molecular simulations and theoretical calculations to be compared with the scattering results. We will describe our experiment, the unique apparatus we have built for it, and the neutron scattering results from our initial allocations of beam time. We will also describe planned scattering experiments to follow those with noble gases, including study of long-chain molecules in supercritical solvents. Such studies will involve hydrocarbon mixtures with and without deuteration to provide contrast

Usage of burnable poison on research reactors

International Nuclear Information System (INIS)

Villarino, Eduardo Anibal

2002-01-01

The fuel assemblies with burnable poison are widely used on power reactors, but there are not commonly used on research reactors. This paper shows a neutronic analysis of the advantages and disadvantages of the burnable poison usage on research reactors. This paper analyses both burnable poison design used on research reactors: Boron on the lateral wall and Cadmium wires. Both designs include a parametric study on the design parameters like the amount and geometry of the burnable poison. This paper presents the design flexibility using burnable poisons, it does not find an optimal or final design, which it will strongly depend on the core characteristics and fuel management strategy. (author)

Determination of As by instrumental neutron activation analysis in sectioned hair samples for forensic purposes: chronic or acute poisoning?

International Nuclear Information System (INIS)

Kucera, J.; Kofronova, K.

2011-01-01

Autopsy of 29-year old woman suspicious of committing suicide by the ingestion of As 2 O 3 yielded contradictory findings. All pathological findings as well as clinical symptoms suggested acute poisoning, while a highly elevated As level of 26.4 μg g -1 in her hair collected at the autopsy, which was determined with inductively coupled plasma mass spectrometry indicated chronic poisoning. To elucidate this discrepancy, instrumental neutron activation analysis (INAA) with proven accuracy was performed of another set of sectioned hair samples. Levels of As found by INAA in the range of 0.16-0.26 μg g -1 excluded chronic poisoning, because the person died after approximately 14 h after the As 2 O 3 ingestion. Two reasons for the discordant As results obtained by ICP-MS and INAA are considered: (1) accidental, non-removed contamination of hair on the As 2 O 3 ingestion; (2) erroneous performance of ICP-MS. (author)

Sharp Reduction in Maximum LEU Fuel Temperatures during Loss of Coolant Accidents in a PBMR DPP-400 core by means of Optimised Placement of Neutron Poisons: Implications for Pu fuel-cycles

International Nuclear Information System (INIS)

Serfontein, Dawid E.

2013-01-01

The optimisation of the power profiles by means of placing an optimised distribution of neutron poison concentrations in the central reflector resulted in a large reduction in the maximum DLOFC temperature, which may produce far reaching safety and licensing benefits. Unfortunately this came at the expense of losing the ability to execute effective load following. The neutron poisons also caused a large reduction of 22% in the average burn-up of the fuel. Further optimisation is required to counter this reduction in burn-up

Criticality effects of longitudinal gaps in poison for storage/transport casks

International Nuclear Information System (INIS)

Wells, A.H.

1985-01-01

A series of criticality calculations was performed with the AMPX/KENO system to determine the sensitivity of the NAC S/T cask 31 assembly basket, which is optimized for a design-basis fuel enrichment of 3.7 wt % 235 U, to axial gaps in the boron neutron poison. The results of these calculations show that axial gaps in the boron cause no statistically detectable change in k/sub eff/ until a minimum gap size is reached. The minimum gap size to change k/sub eff/ is dependent on the basket segment length, because a longer segment length results in fewer gaps for a given active fuel length. Longer segment lengths are less sensitive to gaps in the neutron poison. A typical segment length of 12 to 18 in. is projected for a casting of aluminum/boron alloy, indicating that axial gaps in the neutron poison of 1 in. would be acceptable. This gap thickness is much greater than the intersegment gap produced by modern casting techniques. The investigation described here demonstrated that an axial gap in neutron poison is acceptable for basket castings of large storage/transport casks. A precedent for such gaps is the NLI-6502 cask, so a cask basket with intersegment gaps should be licensable

Burnable poison fuel element and its fabrication

International Nuclear Information System (INIS)

Zukeran, Atsushi; Inoue, Kotaro; Aizawa, Hiroko.

1985-01-01

Purpose: To enable to optionally vary the excess reactivity and fuel reactivity. Method: Burnable poisons with a large neutron absorption cross section are contained in fuel material, by which the excess reactivity at the initial stage in the reactor is suppressed by the burnable poisons and the excess reactivity is released due to the reduction in the atomic number density of the burnable poisons accompanying the burning. The burnable poison comprises spherical or rod-like body made of a single material or spherical or rod-like member made of a plurality kind of materials laminated in a layer. These spheres or rods are dispersed in the fuel material. By adequately selecting the shape, combination and the arrangement of the burnable poisons, the axial power distribution of the fuel rods are flattened. (Moriyama, K.)

Preparation and study of the critical-mass-free plutonium ceramics with neutron poisons Hf, Gd and Li

International Nuclear Information System (INIS)

Timoefeeva, L.F.; Orlov, V.K.; Malyukov, E.E.; Molomin, V.I.; Zhmak, V.A.; Semova, E.A.; Shishkov, N.V.; Nadykto, B.A.

2002-01-01

Powder sintering was used to produce homogeneous type oxide ceramics of Pu with Hf, Gd and Li 6 . In all the ceramics, there is the number of neutron poison (Hf, Gd and Li) atoms per plutonium atom needed, according to the physical calculation, for them to be free of critical mass. PuO 2 stabilizers high-temperature modifications of cubic HfO 2 or hexagonal Gd 2 O 3 , however, at the ratio given by the physical calculation, the plutonium is insufficient for their full stabilization. Addition of yttrium oxide as an additive stabilizing the fcc phase of HfO 2 resulted in cubic solid solution (Pu, Hf, Y)O 2-x . Pu/Li/Hf and Pu/Li/Si ceramics produced by sintering of PuO 2 and compound Li 2 HfO 3 or 6 Li 4 SiO 4 powders is characterized with presence of two phases. The method of differential thermal analysis demonstrated the phase stability of (Pu-Hf, Pu-Gd, Pu-Li-Hf) oxide ceramics in the 20-1500degC temperature range. Ceramic (Pu/Li/Si) has several endothermal effects. Tests in boiling water solutions of various composition suggest that the specimens of Pu, Hf oxides and ternary oxides (Pu, Hf, Y)O 2 are less stable in weakly acidic media than in weakly alkaline medium and distilled water. The obtained results were used as a basis to estimate the assumed solid solution region boundaries for binary Hf, Pu and ternary Hf, Pu, Y oxides on the side of HfO 2 . (author)

Neutronic performance issues for the Spallation Neutron Source moderators

International Nuclear Information System (INIS)

Iverson, E.B.; Murphy, B.D.

2001-01-01

We continue to develop the neutronic models of the Spallation Neutron Source target station and moderators in order to better predict the neutronic performance of the system as a whole and in order to better optimize that performance. While we are not able to say that every model change leads to more intense neutron beams being predicted, we do feel that such changes are advantageous in either performance or in the accuracy of the prediction of performance. We have computationally and experimentally studied the neutronics of hydrogen-water composite moderators such as are proposed for the SNS Project. In performing these studies, we find that the composite moderator, at least in the configuration we have examined, does not provide performance characteristics desirable for the instruments proposed and being designed for this neutron scattering facility. The pulse width as a function of energy is significantly broader than for other moderators, limiting attainable resolution-bandwidth combinations. Furthermore, there is reason to expect that higher-energy (0.1-1 eV) applications will be significantly impacted by bimodal pulse shapes requiring enormous effort to parameterize. As a result of these studies, we have changed the SNS design, and will not use a composite moderator at this time. We have analyzed the depletion of a gadolinium poison plate in a hydrogen moderator at the Spallation Neutron Source, and found that conventional poison thicknesses will be completely unable to last the desired component lifetime of three operational years. A poison plate 300-600 μm thick will survive for the required length of time, but will somewhat degrade the intensity (by as much as 15% depending on neutron energy) and the consistency of the neutron source performance. Our results should scale fairly easily to other moderators on this or any other spallation source. While depletion will be important for all highly-absorbing materials in high-flux regions, we feel it likely that

Adjoint P1 equations solution for neutron slowing down; Solucao das equacoes P1 adjuntas para moderacao de neutrons

Energy Technology Data Exchange (ETDEWEB)

Cardoso, Carlos Eduardo Santos; Martinez, Aquilino Senra; Silva, Fernando Carvalho da [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear

2002-07-01

In some applications of perturbation theory, it is necessary know the adjoint neutron flux, which is obtained by the solution of adjoint neutron diffusion equation. However, the multigroup constants used for this are weighted in only the direct neutron flux, from the solution of direct P1 equations. In this work, the adjoint P1 equations are derived by the neutron transport equation, the reversion operators rules and analogies between direct and adjoint parameters. The direct and adjoint neutron fluxes resulting from the solution of P{sub 1} equations were used to three different weighting processes, to obtain the macrogroup macroscopic cross sections. It was found out noticeable differences among them. (author)

Heterogeneous burnable poisons:

International Nuclear Information System (INIS)

Leiva, Sergio; Agueda, Horacio; Russo, Diego

1989-01-01

The use of materials possessing high neutron absorption cross-section commonly known as 'burnable poisons' have its origin in BWR reactors with the purpose of improving the efficiency of the first fuel load. Later on, it was extended to PWR to compensate of initial reactivity without infringing the requirement of maintaining a negative moderator coefficient. The present tendency is to increase the use of solid burnable poisons to extend the fuel cycle life and discharge burnup. There are two concepts for the burnable poisons utilization: 1) heterogeneously distributions in the form of rods, plates, etc. and 2) homogeneous dispersions of burnable poisons in the fuel. The purpose of this work is to present the results of sinterability studies, performed on Al 2 O 3 -B 4 C and Al 2 O 3 -Gd 2 O 3 systems. Experiments were carried on pressing at room temperature mixtures of powders containing up to 5 wt % of B 4 C or Gd 2 O 3 in Al 2 O 3 and subsequently sintering at 1750 deg C in reducing atmosphere. Evaluation of density, porosity and microstructures were done and a comparison with previous experiences is shown. (Author) [es

Assay of fissionable isotopes in aqueous solution by pulsed neutron interrogation

International Nuclear Information System (INIS)

Campbell, P.; Gardy, E.M.; Boase, D.G.

1978-04-01

Non-destructive assay of uranium-235 and thorium-232 in aqueous nitric acid solutions has been accomplished by irradiation with pulses of neutrons from a 14-MeV Cockcroft-Walton neutron generator, and counting of the delayed neutrons emitted from the fissions induced. Design of the delayed neutron detector assemblies is described, together with the neutron pulse timing and counting systems. The effects of irradiation time, counting time, neutron moderation, detector design and sample geometry on the delayed neutron response from uranium-235 and 238 and thorium-232 are discussed. By using polyethylene to moderate the interrogating neutrons, solutions can be analyzed for both uranium-235 and thorium. Comparative analyses with chemical and γ-spectrometric methods show good agreement. The neutron method is rapid and is shown to be unaffected by the presence in solution of impurities such as iron, nickel, chromium, and aluminum. With the experimental equipment described, detection limits of 0.6 mg of 235 U and 9 mg of 232 Th in a sample volume of 25 mL have been achieved. Analyses of highly radioactive samples may be done easily since the measurements are not affected by the presence of large amounts of βγ radiation. Samples can be enclosed in small lead-shielded flasks during analysis to protect the analyst. The potential of the technique to on-line analysis applications is explored briefly. (author)

Copper sulphate poisoning in horses

Energy Technology Data Exchange (ETDEWEB)

Bauer, M

1975-01-01

In the archives of the Clinic for Internal Diseases of Domestic Animals at the Veterinary Faculty of Zagreb University some thirty cases of horse disease diagnosed as copper sulphate poisoning were noted. The data correspond in many respects to the clinical findings of copper sulphate poisoning in other domestic animals. A series of experimental horse poisonings were undertaken in order to determine the toxicity of copper sulphate. The research results are as follows: Horses are sensitive to copper sulphate. Even a single application of 0.125 g/kg body weight in 1% concentration by means of incubation into the stomach causes stomach and gut disturbances and other poisoning symptoms. Poisoning occurs in two types: acute and chronic. The former appears after one to three applications of copper sulphate solution and is characterized by gastroenteritis, haemolysis, jaundice and haemoglobinuria with signs of consecutive damage of kidney, liver and other organs. The disease, from the first application to death lasts for two weeks. Chronic poisoning is caused by ingestion of dry copper sulphate in food (1% solution dried on hay or clover) for two or more months. There are chronic disturbances of stomach and gut and loss of weight, and consecutive (three to four) haemolytic crises similar to those of acute poisoning. From the beginning of poisoning to death six or more months can elapse.

A three-dimensional neutron transport benchmark solution

International Nuclear Information System (INIS)

Ganapol, B.D.; Kornreich, D.E.

1993-01-01

For one-group neutron transport theory in one dimension, several powerful analytical techniques have been developed to solve the neutron transport equation, including Caseology, Wiener-Hopf factorization, and Fourier and Laplace transform methods. In addition, after a Fourier transform in the transverse plane and formulation of a pseudo problem, two-dimensional (2-D) and three-dimensional (3-D) problems can be solved using the techniques specifically developed for the one-dimensional (1-D) case. Numerical evaluation of the resulting expressions requiring an inversion in the transverse plane have been successful for 2-D problems but becomes exceedingly difficult in the 3-D case. In this paper, we show that by using the symmetry along the beam direction, a 2-D problem can be transformed into a 3-D problem in an infinite medium. The numerical solution to the 3-D problem is then demonstrated. Thus, a true 3-D transport benchmark solution can be obtained from a well-established numerical solution to a 2-D problem

Reactivity effects due to beryllium poisoning of BR2

International Nuclear Information System (INIS)

Kalcheva, S.; Ponsard, B.; Koonen, E.

2004-01-01

This paper illustrates the impact of the poisoning of the beryllium reflector on reactivity variations of the Belgian MTR BR2 in SCK.CEN. Detailed calculations by MCNP-4C of reactivity effects caused by strong neutron absorbers 3 He and 6 Li during reactor operation history are presented. The importance of beryllium poisoning for the accuracy of reactivity predictions is discussed. (authors)

The power of poison: pesticide poisoning of Africa's wildlife.

Science.gov (United States)

Ogada, Darcy L

2014-08-01

Poisons have long been used to kill wildlife throughout the world. An evolution has occurred from the use of plant- and animal-based toxins to synthetic pesticides to kill wildlife, a method that is silent, cheap, easy, and effective. The use of pesticides to poison wildlife began in southern Africa, and predator populations were widely targeted and eliminated. A steep increase has recently been observed in the intensity of wildlife poisonings, with corresponding population declines. However, the majority of poisonings go unreported. Under national laws, it is illegal to hunt wildlife using poisons in 83% of African countries. Pesticide regulations are inadequate, and enforcement of existing legislation is poor. Few countries have forensic field protocols, and most lack storage and testing facilities. Methods used to poison wildlife include baiting carcasses, soaking grains in pesticide solution, mixing pesticides to form salt licks, and tainting waterholes. Carbofuran is the most widely abused pesticide in Africa. Common reasons for poisoning are control of damage-causing animals, harvesting fish and bushmeat, harvesting animals for traditional medicine, poaching for wildlife products, and killing wildlife sentinels (e.g., vultures because their aerial circling alerts authorities to poachers' activities). Populations of scavengers, particularly vultures, have been decimated by poisoning. Recommendations include banning pesticides, improving pesticide regulations and controlling distribution, better enforcement and stiffer penalties for offenders, increasing international support and awareness, and developing regional pesticide centers. © 2014 New York Academy of Sciences.

Neutrons for global energy solutions. Book of abstracts

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

The book of abstracts of the conference on neutrons for global energy solutions include contributions to the following topics: Views from politics: What do we need in European energy research: cooperation, large facilities, more science? Fundamental research for energy supply. View from the United States. View from industry: Neutrons for nuclear reactor development in transition stage between generation III and generation IV. Toyotas's expectations for neutron analysis. Instrumentation and cross cutting issues. Energy sources. Waste management and environment. Li ion batteries. Photovoltaics. Savings and catalysis. Fuel cells. Hydrogen storage.

Neutrons for global energy solutions. Book of abstracts

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

The book of abstracts of the conference on neutrons for global energy solutions include contributions to the following topics: Views from politics: What do we need in European energy research: cooperation, large facilities, more science? Fundamental research for energy supply. View from the United States. View from industry: Neutrons for nuclear reactor development in transition stage between generation III and generation IV. Toyotas's expectations for neutron analysis. Instrumentation and cross cutting issues. Energy sources. Waste management and environment. Li ion batteries. Photovoltaics. Savings and catalysis. Fuel cells. Hydrogen storage.

Neutron dosimetry using aqueous solutions of lithium acetate

International Nuclear Information System (INIS)

Rakovan, L.J.

1996-01-01

A thermal neutron dosimetry system using the 6 Li(n,α) 3 H reaction and liquid scintillation counting of tritium was developed. Lithium acetate was chosen to supply the 6 Li in the aqueous dosimetry solutions. Neutron irradiations were completed using The Ohio State University Research Reactor. After two sets of samples were irradiated, variables in the system such as the mass of lithium acetate in the solutions and the counting window of the liquid scintillation counter used to analyze the sample were chosen. The system was evaluated by completing two sets of 23 minute irradiations with the reactor at 500 kW, 50 kW, 5 kW, and one irradiation at 500 W. The samples irradiated at 500 W were below the threshold of the system, and could not be used. Prompt analysis was essential due to loss of detectable emissions in the dosimetry solutions over time. The thermal neutron fluences calculated with the data from the samples were compared to the fluences determined from gold wire irradiations. The fluence values differed at most by 6%. The fluence values calculated from the samples were consistently less than those determined from the gold wires

Investigation of solid solution of hydrogen in α-manganese by neutron diffraction and inelastic neutron scattering

International Nuclear Information System (INIS)

Fedotov, V.K.; Antonov, V.E.; Kolesnikov, A.I.; Kornell, K.; Vipf, G.; Grosse, G.; Vagner, F.Eh.; Sikolenko, V.V.; Sumin, V.V.; )

1997-01-01

The FCC-lattice of the solid solution α-MnH 0.073 with the mass of 8.45 g is investigated by the neutron diffraction method and the inelastic neutron scattering technique. The neutron diffraction measurements are made by the diffractometer D1B with pyrographite monochromator and the high-resolution Fourier diffractometer HRFD at 300 K. The study of the inelastic incoherent neutron scattering is carried out by means of the inverse geometry spectrometer KDSOG-M at 90 K. The comparative analysis of α-MnH 0.073 and α-Mn spectra is fulfilled for the more correct separation of effects of hydrogen introduction. It is found out that the structure of the solid solution α-MnH 0.073 belongs to the same spatial group I-43m as the structure of α-Mn [ru

Neutronics of pulsed spallation neutron sources

International Nuclear Information System (INIS)

Watanabe, Noboru

2003-01-01

Various topics and issues on the neutronics of pulsed spallation neutron sources, mainly for neutron scattering experiments, are reviewed to give a wide circle of readers a better understanding of these sources in order to achieve a high neutronic performance. Starting from what neutrons are needed, what the spallation reaction is and how to produce slow-neutrons more efficiently, the outline of the target and moderator neutronics are explained. Various efforts with some new concepts or ideas have already been devoted to obtaining the highest possible slow-neutron intensity with desired pulse characteristics. This paper also reviews the recent progress of such efforts, mainly focused on moderator neutronics, since moderators are the final devices of a neutron source, which determine the source performance. Various governing parameters for neutron-pulse characteristics such as material issues, geometrical parameters (shape and dimensions), the target-moderator coupling scheme, the ortho-para-hydrogen ratio, poisoning, etc are discussed, aiming at a high performance pulsed spallation source

Fuel assembly and burnable poison rod

International Nuclear Information System (INIS)

Hirukawa, Koji.

1993-01-01

In a fuel assembly having burnable poison rods arranged therein, the burnable poison comprises an elongate small outer tube and an inner tube coaxially disposed within the outer tube. Upper and lower end tubes each sealed at one end are connected to both of the upper and lower ends in the inner and the outer tubes respectively. A coolant inlet hole is disposed to the lower end tube, while a coolant leakage hole is disposed to the upper end tube. Burnable poison members are filled in an annular space. Further, the burnable poison-filling region is disposed excepting portions for 1/20 - 1/12 of the effective fuel length at each of the upper and the lower ends of the fuel rod. Then, the concentration of the burnable poisons in a region above a boundary defined at a position 1/3 - 1/2, from beneath, of the effective fuel length is made smaller than that in the lower region. This enables to suppress excess reactions of fuels to reduce the mass of the burnable neutron. Excellent reactivity control performance at the initial stage of the burning can be attained. (T.M.)

Irradiation test of borosilicate glass burnable poison

International Nuclear Information System (INIS)

Feng Mingquan; Liao Zumin; Yang Mingjin; Lu Changlong; Huang Deyang; Zeng Wangchun; Zhao Xihou

1991-08-01

The irradiation test and post-irradiation examinations for borosilicate glass burnable poison are introduced. Examinations include visual examination, measurement of dimensions and density, and determination of He gas releasing and 10 B burnup. The corrosion and phenomenon of irradiation densification are also discussed. Two type glass samples have been irradiated with different levels of neutron flux. It proved that the GG-17 borosilicate glass can be used as burnable poison to replace the 10 B stainless steel in the Qinshan Nuclear Power Plant, and it is safe, economical and reasonable

Neutron Collar Evolution and Fresh PWR Assembly Measurements with a New Fast Neutron Passive Collar

Energy Technology Data Exchange (ETDEWEB)

Menlove, Howard Olsen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Geist, William H. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Root, Margaret A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rael, Carlos D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Belian, Anthony P. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-11-02

The passive neutron collar approach removes the effect of poison rods when using a 1mm Gd liner. This project sets out to solve the following challenges: BWR fuel assemblies have less mass and less neutron multiplication than PWR; and effective removal of cosmic ray spallation neutron bursts needed via QC tests.

Iterative solution to the optimal poison management problem in pressurized water reactors

International Nuclear Information System (INIS)

Colletti, J.P.; Levine, S.H.; Lewis, J.B.

1983-01-01

A new method for solving the optimal poison management problem for a multiregion pressurized water reactor has been developed. The optimization objective is to maximize the end-of-cycle core excess reactivity for any given beginning-of-cycle fuel loading. The problem is treated as an optimal control problem with the region burnup and control absorber concentrations acting as the state and control variables, respectively. Constraints are placed on the power peaking, soluble boron concentration, and control absorber concentrations. The solution method consists of successive relinearizations of the system equations resulting in a sequence of nonlinear programming problems whose solutions converge to the desired optimal control solution. Application of the method to several test problems based on a simplified three-region reactor suggests a bang-bang optimal control strategy with the peak power location switching between the inner and outer regions of the core and the critical soluble boron concentration as low as possible throughout the cycle

Comparison of xenon-135 and samarium-149 poisoning in the Miniature Neutron Source Reactor

International Nuclear Information System (INIS)

Khattab, K.

2005-05-01

The Xe-135 equilibrium reactivity was calculated previously using the WIMSD4 and CITATION codes to estimate the fission product poisoning factor in the Syrian Miniature Neutron Source Reactor (MNSR). The fission product poisoning factor was used to calculate the Xe-135 concentrations and reactivities during the reactor operation, at saturation, and after shutdown. The fission product poisoning factor is used in this study to calculate the Sm-149 concentrations and reactivities during the reactor operation, at saturation, and after shutdown. The results are compared with Xe-135 concentrations and reactivities which were calculated before. The Xe-135 concentration increases versus the reactor operation time and reaches 2.836*10 13 atoms/cm 3 after 6 hours, where the Sm-149 concentration reaches 0.745*10 12 atoms/cm 3 . The Xe-135 and Sm-149 reactivities reach -0.451 and -0.256*10 -3 mk respectively after 6 hours of the reactor operation time. It is found that the Xe-135 and Sm-149 reactivities do not reach the equilibrium reactivities during typical reactor daily operating time. The Xe-235 concentration and reactivity are increased and reach to maximum values after 30000 second from the reactor shut down. Its maximum reactivity is -0.903 mk. Hence, the Xe-235 generates -0.452 mk extra reactivity after the reactor shutdown. The Sm-149 concentration and reactivates are increased after the reactor shut down. The Sm-149 reactivity reaches -0.249*10 -2 mk after 100000 second from the reactor shut down, and the Sm-149 introduces -2.231*10 -3 mk extra reactivity after the reactor shut down. Finally, the amount of Sm-149 accumulated in the reactor core after 1, 2, 5, and 10 years of the reactor operation time are: 3.995*10 -3 , 7.694*10 -3 , 17.226*10 -3 , and 2.892*10 -2 grams respectively. (Author)

Neutronic moderator design for the Spallation Neutron Source (SNS)

International Nuclear Information System (INIS)

Charlton, L.A.; Barnes, J.M.; Johnson, J.O.; Gabriel, T.A.

1998-01-01

Neutronics analyses are now in progress to support the initial selection of moderator design parameters for the Spallation Neutron Source (SNS). The results of the initial optimization studies involving moderator poison plate location, moderator position, and premoderator performance for the target system are presented in this paper. Also presented is an initial study of the use of a composite moderator to produce a liquid methane like spectrum

Nuclear fuel saving assessment of poison-free control in LWRs [light water reactors

International Nuclear Information System (INIS)

Abu-Zaied, G.

1988-01-01

If neutron losses to control absorbers are to be eliminated, an alternative reactivity control system has to be introduced. Due to improved neutron economy, the fuel utilization of these other alternatives is better than for a conventional poison-controlled PWR [pressurized water reactor]. It is the objective in this work to assess the uranium savings attributable to reactivity control without poison. An investigation into the savings due to the elimination of PWR control by neutron capture has been carried out. The most important finding was that up to a 30% savings in natural uranium can be achieved if fuel to moderator ratio, V f /V m , of SSC [spectral-shift-control] core at EOC [end of cycle] is similar to the standard core V f /V m

An accurate solution of point reactor neutron kinetics equations of multi-group of delayed neutrons

International Nuclear Information System (INIS)

Yamoah, S.; Akaho, E.H.K.; Nyarko, B.J.B.

2013-01-01

Highlights: ► Analytical solution is proposed to solve the point reactor kinetics equations (PRKE). ► The method is based on formulating a coefficient matrix of the PRKE. ► The method was applied to solve the PRKE for six groups of delayed neutrons. ► Results shows good agreement with other traditional methods in literature. ► The method is accurate and efficient for solving the point reactor kinetics equations. - Abstract: The understanding of the time-dependent behaviour of the neutron population in a nuclear reactor in response to either a planned or unplanned change in the reactor conditions is of great importance to the safe and reliable operation of the reactor. In this study, an accurate analytical solution of point reactor kinetics equations with multi-group of delayed neutrons for specified reactivity changes is proposed to calculate the change in neutron density. The method is based on formulating a coefficient matrix of the homogenous differential equations of the point reactor kinetics equations and calculating the eigenvalues and the corresponding eigenvectors of the coefficient matrix. A small time interval is chosen within which reactivity relatively stays constant. The analytical method was applied to solve the point reactor kinetics equations with six-groups delayed neutrons for a representative thermal reactor. The problems of step, ramp and temperature feedback reactivities are computed and the results compared with other traditional methods. The comparison shows that the method presented in this study is accurate and efficient for solving the point reactor kinetics equations of multi-group of delayed neutrons

Fissile materials in solution concentration measured by active neutron interrogation

International Nuclear Information System (INIS)

Romeyer Dherbey, J.; Passard, Ch.; Cloue, J.; Bignan, G.

1993-01-01

The use of the active neutron interrogation to measure the concentration of plutonium contained in flow solutions is particularly interesting for fuel reprocessing plants. Indeed, this method gives a signal which is in a direct relation with the fissile materials concentration. Moreover, it is less sensitive to the gamma dose rate than the other nondestructive methods. Two measure methods have been evolved in CEA. Their principles are given into details in this work. The first one consists to detect fission delayed neutrons induced by a 252 Cf source. In the second one fission prompt neutrons induced by a neutron generator of 14 MeV are detected. (O.M.)

Minor actinide transmutation on PWR burnable poison rods

International Nuclear Information System (INIS)

Hu, Wenchao; Liu, Bin; Ouyang, Xiaoping; Tu, Jing; Liu, Fang; Huang, Liming; Fu, Juan; Meng, Haiyan

2015-01-01

Highlights: • Key issues associated with MA transmutation are the appropriate loading pattern. • Commercial PWRs are the only choice to transmute MAs in large scale currently. • Considerable amount of MA can be loaded to PWR without disturbing k eff markedly. • Loading MA to PWR burnable poison rods for transmutation is an optimal loading pattern. - Abstract: Minor actinides are the primary contributors to long term radiotoxicity in spent fuel. The majority of commercial reactors in operation in the world are PWRs, so to study the minor actinide transmutation characteristics in the PWRs and ultimately realize the successful minor actinide transmutation in PWRs are crucial problem in the area of the nuclear waste disposal. The key issues associated with the minor actinide transmutation are the appropriate loading patterns when introducing minor actinides to the PWR core. We study two different minor actinide transmutation materials loading patterns on the PWR burnable poison rods, one is to coat a thin layer of minor actinide in the water gap between the zircaloy cladding and the stainless steel which is filled with water, another one is that minor actinides substitute for burnable poison directly within burnable poison rods. Simulation calculation indicates that the two loading patterns can load approximately equivalent to 5–6 PWR annual minor actinide yields without disturbing the PWR k eff markedly. The PWR k eff can return criticality again by slightly reducing the boric acid concentration in the coolant of PWR or removing some burnable poison rods without coating the minor actinide transmutation materials from PWR core. In other words, loading minor actinide transmutation material to PWR does not consume extra neutron, minor actinide just consumes the neutrons which absorbed by the removed control poisons. Both minor actinide loading patterns are technically feasible; most importantly do not need to modify the configuration of the PWR core and

Processing of poison rods with a view to disposal

International Nuclear Information System (INIS)

Bichet, R.; Charamathieu, A.; Lasseur, C.; Golicheff, I.; Pouteaux, M.

1979-01-01

In the core of the French 900 and 1300 MW reactors, a certain number of rods have to be processed as wastes, particularly the burnable poison rods used during reactor start-up (900 MW: 68 rods; 1300 MW: 96 rods). Several solutions are possible: cutting and conditionning in reactor pool; transfer of the poison rods to a cutting and conditionning facility; transfer of the poison rods and fuel assemblies to a storage area where they are cutted and stored. Each of these solutions are studied, the advantages and disadvantages being presented

Contribution to analytical solution of neutron slowing down problem in homogeneous and heterogeneous media

International Nuclear Information System (INIS)

Stefanovic, D.B.

1970-12-01

The objective of this work is to describe the new analytical solution of the neutron slowing down equation for infinite monoatomic media with arbitrary energy dependence of cross section. The solution is obtained by introducing Green slowing down functions instead of starting from slowing down equations directly. The previously used methods for calculation of fission neutron spectra in the reactor cell were numerical. The proposed analytical method was used for calculating the space-energy distribution of fast neutrons and number of neutron reactions in a thermal reactor cell. The role of analytical method in solving the neutron slowing down in reactor physics is to enable understating of the slowing down process and neutron transport. The obtained results could be used as standards for testing the accuracy od approximative and practical methods

Exact analytical solution of time-independent neutron transport equation, and its applications to systems with a point source

International Nuclear Information System (INIS)

Mikata, Y.

2014-01-01

Highlights: • An exact solution for the one-speed neutron transport equation is obtained. • This solution as well as its derivation are believed to be new. • Neutron flux for a purely absorbing material with a point neutron source off the origin is obtained. • Spherically as well as cylindrically piecewise constant cross sections are studied. • Neutron flux expressions for a point neutron source off the origin are believed to be new. - Abstract: An exact analytical solution of the time-independent monoenergetic neutron transport equation is obtained in this paper. The solution is applied to systems with a point source. Systematic analysis of the solution of the time-independent neutron transport equation, and its applications represent the primary goal of this paper. To the best of the author’s knowledge, certain key results on the scalar neutron flux as well as their derivations are new. As an application of these results, a scalar neutron flux for a purely absorbing medium with a spherically piecewise constant cross section and an isotropic point neutron source off the origin as well as that for a cylindrically piecewise constant cross section with a point neutron source off the origin are obtained. Both of these results are believed to be new

Neutron diffusion approximation solution for the the three layer borehole cylindrical geometry. Pt. 1. Theoretical description

International Nuclear Information System (INIS)

Czubek, J.A.; Woznicka, U.

1997-01-01

A solution of the neutron diffusion equation is given for a three layer cylindrical coaxial geometry. The calculation is performed in two neutron-energy groups which distinguish the thermal and epithermal neutron fluxes in the media irradiated by the fast point neutron source. The aim of the calculation is to define the neutron slowing down and migration lengths which are observed at a given point of the system. Generally, the slowing down and migration lengths are defined for an infinite homogenous medium (irradiated by the point neutron source) as a quotient of the neutron flux moment of the (2n + 2)-order to the moment of the 2n-order. Czubek(1992) introduced in the same manner the apparent neutron slowing down length and the apparent migration length for a given multi-region cylindrical geometry. The solutions in the present paper are applied to the method of semi-empirical calibration of neutron well-logging tools. The three-region cylindrical geometry corresponds to the borehole of radius R 1 surrounded by the intermediate region (e.g. mud cake) of thickness (R 2 -R 1 ) and finally surrounded by the geological formation which spreads from R 2 up to infinity. The cylinders of an infinite length are considered. The paper gives detailed solutions for the 0-th, 2-nd and 4-th neutron moments of the neutron fluxes for each neutron energy group and in each cylindrical layer. A comprehensive list of the solutions for integrals containing Bessel functions or their derivatives, which are absent in common tables of integrals, is also included. (author)

HAMCIND, Cell Burnup with Fission Products Poisoning

International Nuclear Information System (INIS)

Abe, Alfredo Y.; Dos Santos, Adimir

2002-01-01

1 - Description of program or function: HAMCIND is a cell burnup code based in a coupling between HAMMER-TECHNION and CINDER. The fission product poisoning is taken into account in an explicit fashion. 2 - Method of solution: The nonlinear coupled set of equations for the neutron transport and nuclide transmutation equations and nuclide transmutation equations in a unit cell is solved by HAMCIND in a quasi-static approach. The spectral transport equation is solved by HAMMER-TECHNION at the beginning of each time-step while the nuclide transmutation equations are solved by CINDER for every time-step. The HAMMER-TECHNION spectral calculations are performed taking into account the fission product contribution to the macroscopic cross sections (fast and thermal), in the inelastic scattering matrix and even in the thermal scattering matrices. 3 - Restrictions on the complexity of the problem: Restrictions and/or limitations for HAMCIND depend upon the local operating system

Solution for the multigroup neutron space kinetics equations by the modified Picard algorithm

International Nuclear Information System (INIS)

Tavares, Matheus G.; Petersen, Claudio Z.; Schramm, Marcelo; Zanette, Rodrigo

2017-01-01

In this work, we used a modified Picards method to solve the Multigroup Neutron Space Kinetics Equations (MNSKE) in Cartesian geometry. The method consists in assuming an initial guess for the neutron flux and using it to calculate a fictitious source term in the MNSKE. A new source term is calculated applying its solution, and so on, iteratively, until a stop criterion is satisfied. For the solution of the fast and thermal neutron fluxes equations, the Laplace Transform technique is used in time variable resulting in a rst order linear differential matrix equation, which are solved by classical methods in the literature. After each iteration, the scalar neutron flux and the delayed neutron precursors are reconstructed by polynomial interpolation. We obtain the fluxes and precursors through Numerical Inverse Laplace Transform using the Stehfest method. We present numerical simulations and comparisons with available results in literature. (author)

Solution for the multigroup neutron space kinetics equations by the modified Picard algorithm

Energy Technology Data Exchange (ETDEWEB)

Tavares, Matheus G.; Petersen, Claudio Z., E-mail: matheus.gulartetavares@gmail.com [Universidade Federal de Pelotas (UFPEL), Capao do Leao, RS (Brazil). Departamento de Matematica e Estatistica; Schramm, Marcelo, E-mail: schrammmarcelo@gmail.com [Universidade Federal de Pelotas (UFPEL), RS (Brazil). Centro de Engenharias; Zanette, Rodrigo, E-mail: rodrigozanette@hotmail.com [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Instituto de Matematica e Estatistica

2017-07-01

In this work, we used a modified Picards method to solve the Multigroup Neutron Space Kinetics Equations (MNSKE) in Cartesian geometry. The method consists in assuming an initial guess for the neutron flux and using it to calculate a fictitious source term in the MNSKE. A new source term is calculated applying its solution, and so on, iteratively, until a stop criterion is satisfied. For the solution of the fast and thermal neutron fluxes equations, the Laplace Transform technique is used in time variable resulting in a rst order linear differential matrix equation, which are solved by classical methods in the literature. After each iteration, the scalar neutron flux and the delayed neutron precursors are reconstructed by polynomial interpolation. We obtain the fluxes and precursors through Numerical Inverse Laplace Transform using the Stehfest method. We present numerical simulations and comparisons with available results in literature. (author)

A new method to measure the U-235 content in fresh LWR fuel assemblies via fast-neutron passive self-interrogation

Science.gov (United States)

Menlove, Howard; Belian, Anthony; Geist, William; Rael, Carlos

2018-01-01

The purpose of this paper is to provide a solution to a decades old safeguards problem in the verification of the fissile concentration in fresh light water reactor (LWR) fuel assemblies. The problem is that the burnable poison (e.g. Gd2O3) addition to the fuel rods decreases the active neutron assay for the fuel assemblies. This paper presents a new innovative method for the verification of the 235U linear mass density in fresh LEU fuel assemblies that is insensitive to the burnable poison content. The technique makes use of the 238U atoms in the fuel rods to self-interrogate the 235U mass. The innovation for the new approach is that the 238U spontaneous fission (SF) neutrons from the rods induces fission reactions (IF) in the 235U that are time correlated with the SF source neutrons. Thus, the coincidence gate counting rate benefits from both the nu-bar of the 238U SF (2.07) and the 235U IF (2.44) for a fraction of the IF reactions. Whereas, the 238U SF background has no time-correlation boost. The higher the detection efficiency, the higher the correlated boost because background neutron counts from the SF are being converted to signal doubles. This time-correlation in the IF signal increases signal/background ratio that provides a good precision for the net signal from the 235U mass. The hard neutron energy spectrum makes the technique insensitive to the burnable poison loading where a Cd or Gd liner on the detector walls is used to prevent thermal-neutron reflection back into the fuel assembly from the detector. We have named the system the fast-neutron passive collar (FNPC).

Solution of two energy-group neutron diffusion equation by triangular elements

International Nuclear Information System (INIS)

Correia Filho, A.

1981-01-01

The application of the triangular finite elements of first order in the solution of two energy-group neutron diffusion equation in steady-state conditions is aimed at. The EFTDN (triangular finite elements in neutrons diffusion) computer code in FORTRAN IV language is developed. The discrete formulation of the diffusion equation is obtained applying the Galerkin method. The power method is used to solve the eigenvalues' problem and the convergence is accelerated through the use of Chebshev polynomials. For the equation systems solution the Gauss method is applied. The results of the analysis of two test-problems are presented. (Author) [pt

Neutron diffusion approximation solution for the the three layer borehole cylindrical geometry. Pt. 1. Theoretical description

Energy Technology Data Exchange (ETDEWEB)

Czubek, J.A.; Woznicka, U. [The H. Niewodniczanski Inst. of Nuclear Physics, Cracow (Poland)

1997-12-31

A solution of the neutron diffusion equation is given for a three layer cylindrical coaxial geometry. The calculation is performed in two neutron-energy groups which distinguish the thermal and epithermal neutron fluxes in the media irradiated by the fast point neutron source. The aim of the calculation is to define the neutron slowing down and migration lengths which are observed at a given point of the system. Generally, the slowing down and migration lengths are defined for an infinite homogenous medium (irradiated by the point neutron source) as a quotient of the neutron flux moment of the (2n{sup +}2)-order to the moment of the 2n-order. Czubek(1992) introduced in the same manner the apparent neutron slowing down length and the apparent migration length for a given multi-region cylindrical geometry. The solutions in the present paper are applied to the method of semi-empirical calibration of neutron well-logging tools. The three-region cylindrical geometry corresponds to the borehole of radius R{sub 1} surrounded by the intermediate region (e.g. mud cake) of thickness (R{sub 2}-R{sub 1}) and finally surrounded by the geological formation which spreads from R{sub 2} up to infinity. The cylinders of an infinite length are considered. The paper gives detailed solutions for the 0-th, 2-nd and 4-th neutron moments of the neutron fluxes for each neutron energy group and in each cylindrical layer. A comprehensive list of the solutions for integrals containing Bessel functions or their derivatives, which are absent in common tables of integrals, is also included. (author) 6 refs, 2 figs

Small angle neutron scattering by polymer solutions

International Nuclear Information System (INIS)

Farnoux, B.; Jannink, G.

1980-08-01

Small angle neutron scattering is an experimental technique introduced since about 10 years for the observation of the polymer conformation in all the concentration range from dilute solution to the melt. After a brief recall of the elementary relations between scattering amplitude, index of refraction and scattered intensity, two concepts related to this last quantity (the contrast and the pair correlation function) are discussed in details

Storage of plutonium and nuclear power plant actinide waste in the form of critical-mass-free ceramics containing neutron poisons

Energy Technology Data Exchange (ETDEWEB)

Nadykto, B.A. [RFNC-VNIIEF, Nizhni Novgorod Region (Russian Federation)

2001-07-01

The nuclear weapons production has resulted in accumulation of a large quantity of plutonium and uranium highly enriched with uranium-235 isotope (many tons). The work under ISTC Project 332B-97 treated the issues of safe plutonium storage through making critical-mass-free plutonium oxide compositions with neutron poisons. This completely excludes immediate utilization (without chemical reprocessing) of retained plutonium in nuclear devices. It is therewith possible to locate plutonium most compactly in the storage facility, which would allow reduction in required storage areas and costs. The issues of the surplus weapon-grade plutonium management and utilization have been comprehensively studied in the recent decade. The issues are treated in multiple scientific publications, conferences, and seminars. At the same time, issues of nuclear power engineering actinide waste storage are studied no less extensively. The general issues are material radioactivity and energy release and nuclear accident hazards due to critical mass generation. Plutonium accumulated in nuclear power plant spent fuel is more accessible than weapon-grade plutonium and can become of higher and higher interest with time as its activity reduces, including as material for nuclear devices. The urgency of plutonium management is presently related not only to accumulation of surplus weapon-grade plutonium, but also to the fact that it is high time to decide what has to be done regarding reactor plutonium. Presently, the possibility of actinide separation from NPP spent nuclear fuel and compact underground burial separately from other (mainly fragment) activity is being considered. Actinide and neutron poison base critical-mass-free ceramic materials (similar to plutonium ceramics) may be useful for this burial method. (author)

Storage of plutonium and nuclear power plant actinide waste in the form of critical-mass-free ceramics containing neutron poisons

International Nuclear Information System (INIS)

Nadykto, B.A.

2001-01-01

The nuclear weapons production has resulted in accumulation of a large quantity of plutonium and uranium highly enriched with uranium-235 isotope (many tons). The work under ISTC Project 332B-97 treated the issues of safe plutonium storage through making critical-mass-free plutonium oxide compositions with neutron poisons. This completely excludes immediate utilization (without chemical reprocessing) of retained plutonium in nuclear devices. It is therewith possible to locate plutonium most compactly in the storage facility, which would allow reduction in required storage areas and costs. The issues of the surplus weapon-grade plutonium management and utilization have been comprehensively studied in the recent decade. The issues are treated in multiple scientific publications, conferences, and seminars. At the same time, issues of nuclear power engineering actinide waste storage are studied no less extensively. The general issues are material radioactivity and energy release and nuclear accident hazards due to critical mass generation. Plutonium accumulated in nuclear power plant spent fuel is more accessible than weapon-grade plutonium and can become of higher and higher interest with time as its activity reduces, including as material for nuclear devices. The urgency of plutonium management is presently related not only to accumulation of surplus weapon-grade plutonium, but also to the fact that it is high time to decide what has to be done regarding reactor plutonium. Presently, the possibility of actinide separation from NPP spent nuclear fuel and compact underground burial separately from other (mainly fragment) activity is being considered. Actinide and neutron poison base critical-mass-free ceramic materials (similar to plutonium ceramics) may be useful for this burial method. (author)

An Explicit Finite Difference scheme for numerical solution of fractional neutron point kinetic equation

International Nuclear Information System (INIS)

Saha Ray, S.; Patra, A.

2012-01-01

Highlights: ► In this paper fractional neutron point kinetic equation has been analyzed. ► The numerical solution for fractional neutron point kinetic equation is obtained. ► Explicit Finite Difference Method has been applied. ► Supercritical reactivity, critical reactivity and subcritical reactivity analyzed. ► Comparison between fractional and classical neutron density is presented. - Abstract: In the present article, a numerical procedure to efficiently calculate the solution for fractional point kinetics equation in nuclear reactor dynamics is investigated. The Explicit Finite Difference Method is applied to solve the fractional neutron point kinetic equation with the Grunwald–Letnikov (GL) definition (). Fractional Neutron Point Kinetic Model has been analyzed for the dynamic behavior of the neutron motion in which the relaxation time associated with a variation in the neutron flux involves a fractional order acting as exponent of the relaxation time, to obtain the best operation of a nuclear reactor dynamics. Results for neutron dynamic behavior for subcritical reactivity, supercritical reactivity and critical reactivity and also for different values of fractional order have been presented and compared with the classical neutron point kinetic (NPK) equation as well as the results obtained by the learned researchers .

Analytical model for performance verification of liquid poison injection system of a nuclear reactor

International Nuclear Information System (INIS)

Kansal, Anuj Kumar; Maheshwari, Naresh Kumar; Vijayan, Pallippattu Krishnan

2014-01-01

Highlights: • One-dimensional modelling of shut down system-2. • Semi-empirical correlation poison jet progression. • Validation of code. - Abstract: Shut down system-2 (SDS-2) in advanced vertical pressure tube type reactor, provides rapid reactor shutdown by high pressure injection of a neutron absorbing liquid called poison, into the moderator in the calandria. Poison inside the calandria is distributed by poison jets issued from holes provided in the injection tubes. Effectiveness of the system depends on the rate and spread of the poison in the moderator. In this study, a transient one-dimensional (1D) hydraulic code, COPJET is developed, to predict the performance of system by predicting progression of poison jet with time. Validation of the COPJET is done with the data available in literature. Thereafter, it is applied for advanced vertical pressure type reactor

Neutron evaluation of burnable poison insertion in pressurized water reactor

International Nuclear Information System (INIS)

Faria, Rochkhudson Batista de

2013-01-01

The development of this work was to match the 'Burn-up Credit Criticality Benchmark - Phase II-D - PWR-UO 2 Assembly Study of Control Rod Effects on Spent Fuel Composition' (case 15), which was modeled using the code MCNP5 and SCALE 6.0. The results of the infinite multiplication factor (k inf ) were compared with those obtained by international institutions. Later we performed in this same benchmark, a sensitivity analysis using SCALE 6.0. Thus, we tested several changes in case 15 of Benchmark, such as insertion of different percentages of burnable poison, changing the number and positions of the rods. In all cases were analyzed, comparisons and discussions about the results. The same methodology was applied to the reactor core of the Nuclear Plant in Brazil, Angra II, initially to evaluate its behavior when subjected to a variation in the percentage of burnable poison and then, introduce changes also in the enrichment of nuclear fuel, doing the appropriate comparisons of results. Considering results and experience gained, the Department of Nuclear Engineering, is prepared to control analysis of reactivity with the use of different types of burnable poisons under the code SCALE 6.0 through its various modules. (author)

An Exact Solution of The Neutron Slowing Down Equation

Energy Technology Data Exchange (ETDEWEB)

Stefanovic, D [Boris Kidric Vinca Institute of Nuclear Sciences, Vinca, Belgrade (Yugoslavia)

1970-07-01

The slowing down equation for an infinite homogeneous monoatomic medium is solved exactly. The cross sections depend on neutron energy. The solution is given in analytical form within each of the lethargy intervals. This analytical form is the sum of probabilities which are given by the Green functions. The calculated collision density is compared with the one obtained by Bednarz and also with an approximate Wigner formula for the case of a resonance not wider than one collision interval. For the special case of hydrogen, the present solution reduces to Bethe's solution. (author)

Development and validation of a model for high pressure liquid poison injection for CANDU-6 shutdown system no.2

International Nuclear Information System (INIS)

Rhee, B.-W.; Jeong, C.J.; Choi, J.H.; Yoo, S.-Y.

2002-01-01

In CANDU reactor one of the two reactor shutdown systems is the liquid poison injection system which injects the highly pressurized liquid neutron poison into the moderator tank via small holes on the nozzle pipes. To ensure the safe shutdown of a reactor it is necessary for the poison curtains generated by jets provide quick, and enough negative reactivity to the reactor during the early stage of the accident. In order to produce the neutron cross section necessary to perform this work, the poison concentration distribution during the transient is necessary. In this study, a set of models for analyzing the transient poison concentration induced by this high pressure poison injection jet activated upon the reactor trip in a CANDU-6 reactor moderator tank has been developed and used to generate the poison concentration distribution of the poison curtains induced by the high pressure jets injected into the vacant region between the calandria tube banks. The poison injection rate through the jet holes drilled on the nozzle pipes is obtained by a 1-D transient hydrodynamic code called, ALITRIG, and this injection rate is used to provide the inlet boundary condition to a 3-D CFD model of the moderator tank based on CFX4.3, an AEA Technology CFD code, to simulate the formation and growth of the poison jet curtain inside the moderator tank. For validation, the current model is validated against a poison injection experiment performed at BARC, India and another poison jet experiment for Generic CANDU-6 performed at AECL, Canada. In conclusion this set of models is considered to predict the experimental results in a physically reasonable and consistent manner. (author)

Parallel solutions of the two-group neutron diffusion equations

International Nuclear Information System (INIS)

Zee, K.S.; Turinsky, P.J.

1987-01-01

Recent efforts to adapt various numerical solution algorithms to parallel computer architectures have addressed the possibility of substantially reducing the running time of few-group neutron diffusion calculations. The authors have developed an efficient iterative parallel algorithm and an associated computer code for the rapid solution of the finite difference method representation of the two-group neutron diffusion equations on the CRAY X/MP-48 supercomputer having multi-CPUs and vector pipelines. For realistic simulation of light water reactor cores, the code employees a macroscopic depletion model with trace capability for selected fission product transients and critical boron. In addition to this, moderator and fuel temperature feedback models are also incorporated into the code. The validity of the physics models used in the code were benchmarked against qualified codes and proved accurate. This work is an extension of previous work in that various feedback effects are accounted for in the system; the entire code is structured to accommodate extensive vectorization; and an additional parallelism by multitasking is achieved not only for the solution of the matrix equations associated with the inner iterations but also for the other segments of the code, e.g., outer iterations

Solution to the monoenergetic time-dependent neutron transport equation with a time-varying source

International Nuclear Information System (INIS)

Ganapol, B.D.

1986-01-01

Even though fundamental time-dependent neutron transport problems have existed since the inception of neutron transport theory, it has only been recently that a reliable numerical solution to one of the basic problems has been obtained. Experience in generating numerical solutions to time-dependent transport equations has indicated that the multiple collision formulation is the most versatile numerical technique for model problems. The formulation coupled with a moment reconstruction of each collided flux component has led to benchmark-quality (four- to five-digit accuracy) numerical evaluation of the neutron flux in plane infinite geometry for any degree of scattering anisotropy and for both pulsed isotropic and beam sources. As will be shown in this presentation, this solution can serve as a Green's function, thus extending the previous results to more complicated source situations. Here we will be concerned with a time-varying source at the center of an infinite medium. If accurate, such solutions have both pedagogical and practical uses as benchmarks against which other more approximate solutions designed for a wider class of problems can be compared

Comparison of analytical transport and stochastic solutions for neutron slowing down in an infinite medium

International Nuclear Information System (INIS)

Jahshan, S.N.; Wemple, C.A.; Ganapol, B.D.

1993-01-01

A comparison of the numerical solutions of the transport equation describing the steady neutron slowing down in an infinite medium with constant cross sections is made with stochastic solutions obtained from tracking successive neutron histories in the same medium. The transport equation solution is obtained using a numerical Laplace transform inversion algorithm. The basis for the algorithm is an evaluation of the Bromwich integral without analytical continuation. Neither the transport nor the stochastic solution is limited in the number of scattering species allowed. The medium may contain an absorption component as well. (orig.)

Application of imaging plate neutron detector to neutron radiography

CERN Document Server

Fujine, S; Kamata, M; Etoh, M

1999-01-01

As an imaging plate neutron detector (IP-ND) has been available for thermal neutron radiography (TNR) which has high resolution, high sensitivity and wide range, some basic characteristics of the IP-ND system were measured at the E-2 facility of the KUR. After basic performances of the IP were studied, images with high quality were obtained at a neutron fluence of 2 to 7x10 sup 8 n cm sup - sup 2. It was found that the IP-ND system with Gd sub 2 O sub 3 as a neutron converter material has a higher sensitivity to gamma-ray than that of a conventional film method. As a successful example, clear radiographs of the flat view for the fuel side plates with boron burnable poison were obtained. An application of the IP-ND system to neutron radiography (NR) is presented in this paper.

Application of synthetic diffusion method in the numerical solution of the equations of neutron transport in slab geometry

International Nuclear Information System (INIS)

Valdes Parra, J.J.

1986-01-01

One of the main problems in reactor physics is to determine the neutron distribution in reactor core, since knowing that, it is possible to calculate the rapidity of occurrence of different nuclear reaction inside the reactor core. Within different theories existing in nuclear reactor physics, is neutron transport the one in which equation who govern the exact behavior of neutronic distribution are developed even inside the proper neutron transport theory, there exist different methods of solution which are approximations to exact solution; still more, with the purpose to reach a more precise solution, the majority of methods have been approached to the obtention of solutions in numerical form with the aim of take the advantages of modern computers, and for this reason a great deal of effort is dedicated to numerical solution of the equations of neutron transport. In agreement with the above mentioned, in this work has been developed a computer program which uses a relatively new techniques known as 'acceleration of synthetic diffusion' which has been applied to solve the neutron transport equation with 'classical schemes of spatial integration' obtaining results with a smaller quantity of interactions, if they compare to done without using such equation (Author)

Exact solutions of the neutron slowing down equation

International Nuclear Information System (INIS)

Dawn, T.Y.; Yang, C.N.

1976-01-01

The problem of finding the exact analytic closed-form solution for the neutron slowing down equation in an infinite homogeneous medium is studied in some detail. The existence and unique properties of the solution of this equation for both the time-dependent and the time-independent cases are studied. A direct method is used to determine the solution of the stationary problem. The final result is given in terms of a sum of indefinite multiple integrals by which solutions of some special cases and the Placzek-type oscillation are examined. The same method can be applied to the time-dependent problem with the aid of the Laplace transformation technique, but the inverse transform is, in general, laborious. However, the solutions of two special cases are obtained explicitly. Results are compared with previously reported works in a variety of cases. The time moments for the positive integral n are evaluated, and the conditions for the existence of the negative moments are discussed

Positive solution of a time and energy dependent neutron transport problem

International Nuclear Information System (INIS)

Pao, C.V.

1975-01-01

A constructive method is given for the determination of a solution and an existence--uniqueness theorem for some nonlinear time and energy dependent neutron transport problems, including the linear transport system. The geometry of the medium under consideration is allowed to be either bounded or unbounded which includes the geometry of a finite or infinite cylinder, a half-space and the whole space R/subm/ (m=1,2,center-dotcenter-dotcenter-dot). Our approach to the problem is by successive approximation which leads to various recursion formulas for the approximations in terms of explicit integrations. It is shown under some Lipschitz conditions on the nonlinear functions, which describe the process of neutrons absorption, fission, and scattering, that the sequence of approximations converges to a unique positive solution. Since these conditions are satisfied by the linear transport equation, all the results for the nonlinear system are valid for the linear transport problem. In the general nonlinear problem, the existence of both local and global solutions are discussed, and an iterative process for the construction of the solution is given

Development of Improved Burnable Poisons for Commercial Nuclear Power Reactors

International Nuclear Information System (INIS)

Grossbeck, M. L.; Renier, J-P.A.; Bigelow, Tim

2003-01-01

Burnable poisons are used in nuclear reactors to produce a more level distribution of power in the reactor core and to reduce to necessity for a large control system. An ideal burnable poison would burn at the same rate as the fuel. In this study, separation of neutron-absorbing isotopes was investigated in order to eliminate isotopes that remain as absorbers at the end of fuel life, thus reducing useful fuel life. The isotopes Gd-157, Dy-164, and Er-167 were found to have desirable properties. These isotopes were separated from naturally occurring elements by means of plasma separation to evaluate feasibility and cost. It was found that pure Gd-157 could save approximately $6 million at the end of four years. However, the cost of separation, using the existing facility, made separation cost- ineffective. Using a magnet with three times the field strength is expected to reduce the cost by a factor of ten, making isotopically separated burnable poisons a favorable method of increasing fuel life in commercial reactors, in particular Generation-IV reactors. The project also investigated various burnable poison configurations, and studied incorporation of metallic burnable poisons into fuel cladding

Exact solution of equations for proton localization in neutron star matter

Science.gov (United States)

Kubis, Sebastian; Wójcik, Włodzimierz

2015-11-01

The rigorous treatment of proton localization phenomenon in asymmetric nuclear matter is presented. The solution of proton wave function and neutron background distribution is found by the use of the extended Thomas-Fermi approach. The minimum of energy is obtained in the Wigner-Seitz approximation of a spherically symmetric cell. The analysis of four different nuclear models suggests that the proton localization is likely to take place in the interior of a neutron star.

Analysis of cadmium in high alpha solutions

International Nuclear Information System (INIS)

Gray, L.W.; Overman, L.A.; Hodgens, H.F.

1977-07-01

Cadmium nitrate is occasionally used as a neutron poison for convenience in the separation of uranium, neptunium, and plutonium. As the classical methods of analysis for cadmium are very time-consuming, a method to isolate it in solution using solvent extraction of uranium, neptunium, and plutonium with TBP in an n-paraffin hydrocarbon was investigated. After removal of the radionuclides, the cadmium is determined by atomic absorption spectroscopy. Precision of the method at the 95 percent confidence level is +-2.4 percent. Alpha content of the solutions was typically reduced from 1-10 x 10 11 dis/(min ml) 238 Pu to 1-15 x 10 4 dis/(min ml). Analysis time was typically reduced from approximately 24 hours per sample to less than 1 hour

Neutron noise calculations in a hexagonal geometry and comparison with analytical solutions

International Nuclear Information System (INIS)

Tran, H. N.; Demaziere, C.

2012-01-01

This paper presents the development of a neutronic and kinetic solver for hexagonal geometries. The tool is developed based on the diffusion theory with multi-energy groups and multi-groups of delayed neutron precursors allowing the solutions of forward and adjoint problems of static and dynamic states, and is applicable to both thermal and fast systems with hexagonal geometries. In the dynamic problems, the small stationary fluctuations of macroscopic cross sections are considered as noise sources, and then the induced first order noise is calculated fully in the frequency domain. Numerical algorithms for solving the static and noise equations are implemented with a spatial discretization based on finite differences and a power iterative solution. A coarse mesh finite difference method has been adopted for speeding up the convergence. Since no other numerical tool could calculate frequency-dependent noise in hexagonal geometry, validation calculations have been performed and benchmarked to analytical solutions based on a 2-D homogeneous system with two-energy groups and one-group of delayed neutron precursor, in which point-like perturbations of thermal absorption cross section at central and non-central positions are considered as noise sources. (authors)

Diffuse neutron scattering study of metallic interstitial solid solutions

International Nuclear Information System (INIS)

Barberis, P.

1991-10-01

We studied two interstitial solid solutions (Ni-C(1at%) and Nb-O(2at%) and two stabilized zirconia (ZrO2-CaO(13.6mol%) and ZrO2-Y2O3(9.6mol%) by elastic diffuse neutron scattering. We used polarized neutron scattering in the case of the ferromagnetic Ni-based sample, in order to determine the magnetic perturbation induced by the C atoms. Measurements were made on single crystals in the Laboratoire Leon Brillouin (CEA-CNRS, Saclay, France). An original algorithm to deconvolve time-of-flight spectra improved the separation between elastically and inelastically scattered intensities. In the case of metallic solutions, we used a simple non-linear model, assuming that interstitials are isolated and located in octahedral sites. Results are: - in both compounds, nearest neighbours are widely displaced away from the interstitial, while next nearest neighbours come slightly closer. - the large magnetic perturbation induced by carbon in Nickel decreases with increasing distance on the three first neighbour shells and is in good agreement with the total magnetization variation. - no chemical order between solute atoms could be evidenced. Stabilized zirconia exhibit a strong correlation between chemical order and the large displacements around vacancies and dopants. (Author). 132 refs., 38 figs., 13 tabs

Solution of Point Reactor Neutron Kinetics Equations with Temperature Feedback by Singularly Perturbed Method

Directory of Open Access Journals (Sweden)

Wenzhen Chen

2013-01-01

Full Text Available The singularly perturbed method (SPM is proposed to obtain the analytical solution for the delayed supercritical process of nuclear reactor with temperature feedback and small step reactivity inserted. The relation between the reactivity and time is derived. Also, the neutron density (or power and the average density of delayed neutron precursors as the function of reactivity are presented. The variations of neutron density (or power and temperature with time are calculated and plotted and compared with those by accurate solution and other analytical methods. It is shown that the results by the SPM are valid and accurate in the large range and the SPM is simpler than those in the previous literature.

Optimisation studies for a moderator on a pulsed neutron source

International Nuclear Information System (INIS)

Picton, D.J.; Ross, D.K.; Taylor, A.D.

1982-01-01

Having reviewed general aspects of moderator design for pulsed neutron sources, calculations are presented on a number of aspects of moderator optimization. Results of time-independent calculations on metal hydride moderators and a detailed method of evaluating moderated pulse intensities and time distributions, are given. Using computer codes, neutron cross-sections have been calculated from vibrational frequency distributions and time-dependent moderator calculations performed by Monte Carlo methods. The choice of an ambient moderator material and the optimum configuration of heterogeneous poisoning are examined and evaluations of liquid-nitrogen-cooled moderators are presented. Conclusions are drawn concerning the relative merits of cooled and poisoned moderators and an evaluation presented of solid methane at 20 K as a moderator for the production of cold neutrons. (U.K.)

Prototype Stilbene Neutron Collar

Energy Technology Data Exchange (ETDEWEB)

Prasad, M. K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Shumaker, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Snyderman, N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Verbeke, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wong, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2016-10-26

A neutron collar using stilbene organic scintillator cells for fast neutron counting is described for the assay of fresh low enriched uranium (LEU) fuel assemblies. The prototype stilbene collar has a form factor similar to standard He-3 based collars and uses an AmLi interrogation neutron source. This report describes the simulation of list mode neutron correlation data on various fuel assemblies including some with neutron absorbers (burnable Gd poisons). Calibration curves (doubles vs ²³⁵U linear mass density) are presented for both thermal and fast (with Cd lining) modes of operation. It is shown that the stilbene collar meets or exceeds the current capabilities of He-3 based neutron collars. A self-consistent assay methodology, uniquely suited to the stilbene collar, using triples is described which complements traditional assay based on doubles calibration curves.

Acceleration of criticality analysis solution convergence by matrix eigenvector for a system with weak neutron interaction

Energy Technology Data Exchange (ETDEWEB)

Nomura, Yasushi; Takada, Tomoyuki; Kuroishi, Takeshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kadotani, Hiroyuki [Shizuoka Sangyo Univ., Iwata, Shizuoka (Japan)

2003-03-01

In the case of Monte Carlo calculation to obtain a neutron multiplication factor for a system of weak neutron interaction, there might be some problems concerning convergence of the solution. Concerning this difficulty in the computer code calculations, theoretical derivation was made from the general neutron transport equation and consideration was given for acceleration of solution convergence by using the matrix eigenvector in this report. Accordingly, matrix eigenvector calculation scheme was incorporated together with procedure to make acceleration of convergence into the continuous energy Monte Carlo code MCNP. Furthermore, effectiveness of acceleration of solution convergence by matrix eigenvector was ascertained with the results obtained by applying to the two OECD/NEA criticality analysis benchmark problems. (author)

Development of Improved Burnable Poisons for Commercial Nuclear Power Reactors

Energy Technology Data Exchange (ETDEWEB)

Renier, J.A.

2002-04-17

Burnable poisons are used in all modern nuclear reactors to permit higher loading of fuel without the necessity of an overly large control rod system. This not only permits a longer core life but can also be used to level the power distribution. Commercial nuclear reactors commonly use B{sub 4}C in separate non-fueled rods and more recently, zirconium boride coatings on the fuel pellets or gadolinium oxide mixed with the fuel. Although the advantages are great, there are problems with using these materials. Boron, which is an effective neutron absorber, transmutes to lithium and helium upon absorption of a neutron. Helium is insoluble and is eventually released to the interior of the fuel rod, where it produces an internal pressure. When sufficiently high, this pressure stress could cause separation of the cladding from the fuel, causing overly high centerline temperatures. Gadolinium has several very strongly absorbing isotopes, but not all have large cross sections and result in residual burnable poison reactivity worth at the end of the fuel life. Even if the amount of this residual absorber is small and the penalty in operation small, the cost of this penalty, even if only several days, can be very high. The objective of this investigation was to study the performance of single isotopes in order to reduce the residual negative reactivity left over at the end of the fuel cycle. Since the behavior of burnable poisons can be strongly influenced by their configuration, four forms for the absorbers were studied: homogeneously mixed with the fuel, mixed with only the outer one-third of the fuel pellet, coated on the perimeter of the fuel pellets, and alloyed with the cladding. In addition, the numbers of fuel rods containing burnable poison were chosen as 8, 16, 64, and 104. Other configurations were chosen for a few special cases. An enrichment of 4.5 wt% {sup 235}U was chosen for most cases for study in order to achieve a 4-year fuel cycle. A standard pressurized

Spherical harmonics and energy polynomial solution of the Boltzmann equation for neutrons, 1

International Nuclear Information System (INIS)

Toledo, P.S. de

1974-01-01

The approximate solution of the source-free energy-dependent Boltzmann transport equation for neutrons in plane geometry and isotropic scattering case was given by Leonard and Ferziger using a truncated development in a series of energy-polynomials for the energy dependent neutron flux and solving exactly for the angular dependence. The presence in the general solution of eigenfunctions belonging to a continuous spectrum gives rise to difficult analytical problems in the application of their method even to simple problems. To avoid such difficulties, the angular dependence is treated by a spherical harmonics method and a general solution of the energy-dependent transport equation in plane geometry and isotropic scattering is obtained, in spite of the appearance of matrices as argument of the angular polynomials [pt

Solution of the multilayer multigroup neutron diffusion equation in cartesian geometry by fictitious borders power method

Energy Technology Data Exchange (ETDEWEB)

Zanette, Rodrigo; Petersen, Caudio Zen [Univ. Federal de Pelotas, Capao do Leao (Brazil). Programa de Pos Graduacao em Modelagem Matematica; Schramm, Marcello [Univ. Federal de Pelotas (Brazil). Centro de Engenharias; Zabadal, Jorge Rodolfo [Univ. Federal do Rio Grande do Sul, Tramandai (Brazil)

2017-05-15

In this paper a solution for the one-dimensional steady state Multilayer Multigroup Neutron Diffusion Equation in cartesian geometry by Fictitious Borders Power Method and a perturbative analysis of this solution is presented. For each new iteration of the power method, the neutron flux is reconstructed by polynomial interpolation, so that it always remains in a standard form. However when the domain is long, an almost singular matrix arises in the interpolation process. To eliminate this singularity the domain segmented in R regions, called fictitious regions. The last step is to solve the neutron diffusion equation for each fictitious region in analytical form locally. The results are compared with results present in the literature. In order to analyze the sensitivity of the solution, a perturbation in the nuclear parameters is inserted to determine how a perturbation interferes in numerical results of the solution.

Absorber management using burnable poisons

International Nuclear Information System (INIS)

Mortensen, L.

1977-06-01

An investigation of the problem of optimal control carried out by means of a two-dimensional model of a PWR reactor. A solution is found to the problem, and the possibility of achieving optimal control with burnable poisons such as boron, cadmium and gadolinium is discussed. Further, an attempt is made to solve the control problem of BWR, but no final solution is found. (author)

Structure solution from powder neutron and x-ray diffraction data: getting the best of both worlds

International Nuclear Information System (INIS)

Hunter, B.A.

2000-01-01

Full text: Powder diffraction methods have traditionally been used in three main areas: phase identification and quantification, lattice parameter determination and structure refinement. Until recently structure solution has been the almost exclusive domain of single crystal diffraction methods, predominantly using x-rays. The increasing use of synchrotron and neutron sources, and the unrelenting advances in computing hardware and software means that powder methods are challenging single crystal methods as a practical method for structure solution, especially when single crystal method can not be applied. It is known that structural refinements from a known starting structure using combined X-ray and neutron data sets are capable of providing highly accurate structures. Likewise, using combined x-ray and neutron powder diffraction data in the structure solution process should also be a powerful technique, although to date no one is pursuing this methodology. This paper present examples of solutions to the problem. Namely we are using high resolution powder X-ray and neutron methods to solve the structures of molecular materials and minerals, then refining the structures using both sets of data. In this way we exploit the advantages of both methods while minimising the disadvantages. We present our solution for a small amino acid structure, a metalorganic and a mineral structure

Arbitrary quadrature: its application in the solution of one-dimensional, planar neutron transport problems

International Nuclear Information System (INIS)

Sanchez, J.

2010-10-01

A standard numerical procedure for the solution of singular integral equations is applied to the one-dimensional transport equation for monoenergetic neutrons. As is usual in quadrature methods, the procedure yields an Eigen system whose solution provide, for the critical slab, both the eigenvalue which is proportional to the number of secondary neutrons per collision, and the density as a function of position. The results obtained with two versions of the procedure, differing only in the extent of the basic region to which they are applied, are compared with analytically derived results available for benchmarking. The procedures considered yield consistent results for the calculated neutron densities and eigenvalues. Since the one-dimensional transport kernel and its spatial moments are integrable and their integrals can be put in terms of exponential integral functions, the resulting approximations to the neutron density yield somewhat lengthy but closed, forms. These approximate expressions of the neutron density can be used to render, after they are operated on, closed-form formulas for build-up factors, extrapolation distances or angular densities or employed for other purposes that require an analytical expression of the neutron density. As an example of this latter capability, the results of the calculation of the angular density at the surface of the slab are provided. (Author)

Solution of two-dimensional equations of neutron transport in 4P0-approximation of spherical harmonics method

International Nuclear Information System (INIS)

Polivanskij, V.P.

1989-01-01

The method to solve two-dimensional equations of neutron transport using 4P 0 -approximation is presented. Previously such approach was efficiently used for the solution of one-dimensional problems. New an attempt is made to apply the approach to solution of two-dimensional problems. Algorithm of the solution is given, as well as results of test neutron-physical calculations. A considerable as compared with diffusion approximation is shown. 11 refs

Burnable neutron absorbers

International Nuclear Information System (INIS)

Radford, K.C.; Carlson, W.G.

1985-01-01

This patent deals with the fabrication of pellets for neutron absorber rods. Such a pellet includes a matrix of a refractory material which may be aluminum or zirconium oxide, and a burnable poison distributed throughout the matrix. The neutron absorber material may consist of one or more elements or compounds of the metals boron, gadolinium, samarium, cadmium, europium, hafnium, dysprosium and indium. The method of fabricating pellets of these materials outlined in this patent is designed to produce pores or voids in the pellets that can be used to take up the expansion of the burnable poison and to absorb the helium gas generated. In the practice of this invention a slurry of Al 2 O 3 is produced. A hard binder is added and the slurry and binder are spray dried. This powder is mixed with dry B 4 C powder, forming a homogeneous mixture. This mixture is pressed into green tubes which are then sintered. During sintering the binder volatilizes leaving a ceramic with nearly spherical high-density regions of

Solution of the neutron point kinetics equations with temperature feedback effects applying the polynomial approach method

International Nuclear Information System (INIS)

Tumelero, Fernanda; Petersen, Claudio Z.; Goncalves, Glenio A.; Lazzari, Luana

2015-01-01

In this work, we present a solution of the Neutron Point Kinetics Equations with temperature feedback effects applying the Polynomial Approach Method. For the solution, we consider one and six groups of delayed neutrons precursors with temperature feedback effects and constant reactivity. The main idea is to expand the neutron density, delayed neutron precursors and temperature as a power series considering the reactivity as an arbitrary function of the time in a relatively short time interval around an ordinary point. In the first interval one applies the initial conditions of the problem and the analytical continuation is used to determine the solutions of the next intervals. With the application of the Polynomial Approximation Method it is possible to overcome the stiffness problem of the equations. In such a way, one varies the time step size of the Polynomial Approach Method and performs an analysis about the precision and computational time. Moreover, we compare the method with different types of approaches (linear, quadratic and cubic) of the power series. The answer of neutron density and temperature obtained by numerical simulations with linear approximation are compared with results in the literature. (author)

Solution of the neutron point kinetics equations with temperature feedback effects applying the polynomial approach method

Energy Technology Data Exchange (ETDEWEB)

Tumelero, Fernanda, E-mail: fernanda.tumelero@yahoo.com.br [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Petersen, Claudio Z.; Goncalves, Glenio A.; Lazzari, Luana, E-mail: claudiopeteren@yahoo.com.br, E-mail: gleniogoncalves@yahoo.com.br, E-mail: luana-lazzari@hotmail.com [Universidade Federal de Pelotas (DME/UFPEL), Capao do Leao, RS (Brazil). Instituto de Fisica e Matematica

2015-07-01

In this work, we present a solution of the Neutron Point Kinetics Equations with temperature feedback effects applying the Polynomial Approach Method. For the solution, we consider one and six groups of delayed neutrons precursors with temperature feedback effects and constant reactivity. The main idea is to expand the neutron density, delayed neutron precursors and temperature as a power series considering the reactivity as an arbitrary function of the time in a relatively short time interval around an ordinary point. In the first interval one applies the initial conditions of the problem and the analytical continuation is used to determine the solutions of the next intervals. With the application of the Polynomial Approximation Method it is possible to overcome the stiffness problem of the equations. In such a way, one varies the time step size of the Polynomial Approach Method and performs an analysis about the precision and computational time. Moreover, we compare the method with different types of approaches (linear, quadratic and cubic) of the power series. The answer of neutron density and temperature obtained by numerical simulations with linear approximation are compared with results in the literature. (author)

Initial study on burnable poisons in the Dragon HTR design

Energy Technology Data Exchange (ETDEWEB)

Hansen, U; Pedersen, J

1971-06-15

A first study on the effects of burnable poisons in a High Temperature Reactor is given in this paper, and some of the problems concerning the layout and distribution of burnable poison sticks in the core are explained. Time has not allowed us to obtain satisfactory solutions to these problems, but we hope, that this study could form the basis of valuable discussions on ways and means to overcome the difficulties of burnable poison management in HTRs.

An analytical solution for the two-group kinetic neutron diffusion equation in cylindrical geometry

International Nuclear Information System (INIS)

Fernandes, Julio Cesar L.; Vilhena, Marco Tullio; Bodmann, Bardo Ernst

2011-01-01

Recently the two-group Kinetic Neutron Diffusion Equation with six groups of delay neutron precursor in a rectangle was solved by the Laplace Transform Technique. In this work, we report on an analytical solution for this sort of problem but in cylindrical geometry, assuming a homogeneous and infinite height cylinder. The solution is obtained applying the Hankel Transform to the Kinetic Diffusion equation and solving the transformed problem by the same procedure used in the rectangle. We also present numerical simulations and comparisons against results available in literature. (author)

Optimization of PWR fuel assembly radial enrichment and burnable poison location based on adaptive simulated annealing

International Nuclear Information System (INIS)

Rogers, Timothy; Ragusa, Jean; Schultz, Stephen; St Clair, Robert

2009-01-01

The focus of this paper is to present a concurrent optimization scheme for the radial pin enrichment and burnable poison location in PWR fuel assemblies. The methodology is based on the Adaptive Simulated Annealing (ASA) technique, coupled with a neutron lattice physics code to update the cost function values. In this work, the variations in the pin U-235 enrichment are variables to be optimized radially, i.e., pin by pin. We consider the optimization of two categories of fuel assemblies, with and without Gadolinium burnable poison pins. When burnable poisons are present, both the radial distribution of enrichment and the poison locations are variables in the optimization process. Results for 15 x 15 PWR fuel assembly designs are provided.

A comparison of certain variational solutions of neutron diffusion equation

International Nuclear Information System (INIS)

Altiparmakov, D.V.; Milgram, M.S.

1987-01-01

Using the R-function theory and the variational method of Kantorovich, an approximate solution of the neutron diffusion equation is constructed for a homogeneous spatial domain of arbitrary shape. Calculations have been carried out by five different types of trial functions for certain characteristic domains of polygonal shape (square, triangle, hexagon, rhombus nad L-shaped domain). In the case of non-convex polygons, the consequence of the R-function solution is very poor and a separate treatment of singularity seems to be necessary. Compared to the R-function solution, the singular function development is mathematically more complicated but superior in respect to convergence rate. (author)

High-resolution neutron spectroscopy on protein solution samples

International Nuclear Information System (INIS)

Grimaldo, M.; Henning, M.; Roosen-Runge, F.; Seydel, T.; Jalarvo, N.; Zamponi, M.; Zanini, F.; Zhang, F.; Schreiber, F.

2015-01-01

Proteins in solution are subject to a complex superposition of global translational and rotational diffusion as well as internal relaxations covering a wide range of time scales. With the advent of new high-flux neutron spectrometers in combination with enhanced analysis frameworks it has become possible to separate these different contributions. We discuss new approaches to the analysis by presenting example spectra and fits from data recorded on the backscattering spectrometers IN16, IN16B, and BASIS on the same protein solution sample. We illustrate the separation of the rotational and translational diffusion contribution, the accurate treatment of the solvent contribution, and the extraction of information on internal fluctuations. We also highlight the progress made in passing from second- to third-generation backscattering spectrometers. (authors)

On the Solution of the Neutron Transport Equation

Energy Technology Data Exchange (ETDEWEB)

Depken, S

1962-12-15

The neutron transport equation has occupied the attention of many authors since Placzek, Wick and others made their first attempts to solve it, Even in the simple case of energy independent cross-sections, and disregarding the motion of the scattering nucleons, it is difficult to find a solution in an analytical form which is easily surveyable and fitted for numerical calculations. In Part I of this paper some new viewpoints will be introduced which enable the solution to be presented in its simplest possible form. Part II is devoted to an investigation of some functions introduced in Part I. In Part III the results are applied to the case of large energy lethargy, and the validity of derived formulas is discussed.

Multipolar electromagnetic fields around neutron stars: general-relativistic vacuum solutions

Science.gov (United States)

Pétri, J.

2017-12-01

Magnetic fields inside and around neutron stars are at the heart of pulsar magnetospheric activity. Strong magnetic fields are responsible for quantum effects, an essential ingredient to produce leptonic pairs and the subsequent broad-band radiation. The variety of electromagnetic field topologies could lead to the observed diversity of neutron star classes. Thus, it is important to include multipolar components to a presumably dominant dipolar magnetic field. Exact analytical solutions for these multipoles in Newtonian gravity have been computed in recent literature. However, flat space-time is not adequate to describe physics in the immediate surroundings of neutron stars. We generalize the multipole expressions to the strong gravity regime by using a slowly rotating metric approximation such as the one expected around neutron stars. Approximate formulae for the electromagnetic field including frame dragging are computed from which we estimate the Poynting flux and the braking index. Corrections to leading order in compactness and spin parameter are presented. As far as spin-down luminosity is concerned, it is shown that frame dragging remains irrelevant. For high-order multipoles starting from the quadrupole, the electric part can radiate more efficiently than the magnetic part. Both analytical and numerical tools are employed.

On the numerical solution of the neutron fractional diffusion equation

International Nuclear Information System (INIS)

Maleki Moghaddam, Nader; Afarideh, Hossein; Espinosa-Paredes, Gilberto

2014-01-01

Highlights: • The new version of neutron diffusion equation which established on the fractional derivatives is presented. • The Neutron Fractional Diffusion Equation (NFDE) is solved in the finite differences frame. • NFDE is solved using shifted Grünwald-Letnikov definition of fractional operators. • The results show that “K eff ” strongly depends on the order of fractional derivative. - Abstract: In order to core calculation in the nuclear reactors there is a new version of neutron diffusion equation which is established on the fractional partial derivatives, named Neutron Fractional Diffusion Equation (NFDE). In the NFDE model, neutron flux in each zone depends directly on the all previous zones (not only on the nearest neighbors). Under this circumstance, it can be said that the NFDE has the space history. We have developed a one-dimension code, NFDE-1D, which can simulate the reactor core using arbitrary exponent of differential operators. In this work a numerical solution of the NFDE is presented using shifted Grünwald-Letnikov definition of fractional derivative in finite differences frame. The model is validated with some numerical experiments where different orders of fractional derivative are considered (e.g. 0.999, 0.98, 0.96, and 0.94). The results show that the effective multiplication factor (K eff ) depends strongly on the order of fractional derivative

Solution of two-dimensional neutron diffusion equation for triangular region by finite Fourier transformation

International Nuclear Information System (INIS)

Kobayashi, Keisuke; Ishibashi, Hideo

1978-01-01

A two-dimensional neutron diffusion equation for a triangular region is shown to be solved by the finite Fourier transformation. An application of the Fourier transformation to the diffusion equation for triangular region yields equations whose unknowns are the expansion coefficients of the neutron flux and current in Fourier series or Legendre polynomials expansions only at the region boundary. Some numerical calculations have revealed that the present technique gives accurate results. It is shown also that the solution using the expansion in Legendre polynomials converges with relatively few terms even if the solution in Fourier series exhibits the Gibbs' phenomenon. (auth.)

Study on thermal neutron spectra in reactor moderators by time-of-flight method

International Nuclear Information System (INIS)

Akino, Fujiyoshi

1982-12-01

Prediction of thermal neutron spectra in a reactor core plays very important role in the neutronic design of the reactor for obtaining the accurate thermal group constants. It is well known that the neutron scattering properties of the moderator materials markedly influence the thermal neutron spectra. Therefore, 0 0 angular dependent thermal neutron spectra were measured by the time-of-flight method in the following moderator bulks 1) Graphite bulk poisoned with boron at the temperatures from 20 to 800 0 C, 2) Light water bulk poisoned with Cadmium and/or Indium, 3) Light water-natural uranium heterogeneous bulk. The measured results were compared with calculation utilizing Young-Koppel and Haywood scattering model for graphite and light water respectively. On the other hand, a variety of 20% enriched uranium loaded and graphite moderated cores consisting of the different lattice cell in a wide range of the carbon to uranium atomic ratio have been built at Semi-Homogeneous Critical Experimental Assembly (SHE) to perform the critical experiments related to Very High Temperature Reactor (VHTR). The experimental data were for the critical masses in 235 U, reactivity worths of experimental burnable poison rods, thorium rods, natural-uranium rods and experimental control rods and kinetic parameters. It is made clear from comparison between measurement and calculation that the accurate thermal group constants can be obtained by use of the Young-Koppel and Haywood neutron scattering models if heterogeneity of reactor core lattices is taken into account precisely. (author)

Presentation of some methods for the solution of the monoenergetic neutrons transport equation

International Nuclear Information System (INIS)

Valle G, E. del.

1978-01-01

The neutrons transport theory problems whose solution has been reached were collected in order to show that the transport equation is so complicated that different techniques were developed so as to give approximative numerical solutions to problems concerning the practical application. Such a technique, which had not been investigated in the literature dealing with these problems, is described here. The results which were obtained through this technique in undimensional problems of criticity are satisfactory and speaking in a conceptual way this method is extremely simple because it times. There is no limitation to deal with problems related neutrons sources with an arbitrary distribution and in principle the application of this technique can be extended to unhomogeneous environments. (author)

Operation databook of the fuel treatment system of the Static Experiment Critical Facility (STACY) and the Transient Experiment Critical Facility (TRACY). JFY 2004 to JFY 2008

International Nuclear Information System (INIS)

Kokusen, Junya; Sumiya, Masato; Seki, Masakazu; Kobayashi, Fuyumi; Ishii, Junichi; Umeda, Miki

2013-02-01

Uranyl nitrate solution fuel used in the Static Experiment Critical Facility (STACY) and the Transient Experiment Critical Facility (TRACY) is adjusted in the Fuel Treatment System, in which such parameters are varied as concentration of uranium, free nitric acid, soluble neutron poison, and so on. Operations for concentration and denitration of the solution fuel were carried out with an evaporator from JFY 2004 to JFY 2008 in order to adjust the fuel to the experimental condition of the STACY and the TRACY. In parallel, the solution fuel in which some kinds of soluble neutron poison were doped was also adjusted in JFY 2005 and JFY 2006 for the purpose of the STACY experiments to determine neutron absorption effects brought by fission products, etc. After these experiments in the STACY, a part of the solution fuel including the soluble neutron poison was purified by the solvent extraction method with mixer-settlers in JFY 2006 and JFY 2007. This report summarizes operation data of the Fuel Treatment System from JFY 2004 to JFY 2008. (author)

On solution to the problem of reactor kinetics with delayed neutrons by Monte Carlo method

International Nuclear Information System (INIS)

Kyncl, Jan

2013-07-01

The initial value problem is addressed for the neutron transport equation and for the system of equations that describe the behaviour of emitters of delayed neutrons. Examination of the solution to this problem is based on several main assumptions concerning the behaviour of macroscopic effective cross-sections describing the reaction of the neutron with the medium, the temperature of medium and the remaining parameters of the equations. Formulation of these assumptions is adequately general and is in agreement with the properties of all known models of the physical quantities involved. Among others, the assumptions admit dependence of the macroscopic effective cross-sections and temperature on spatial coordinates and time that can be arbitrary to a great extent. The problem starts from a set of integro-differential equations. This problem is first transposed into the equivalent problem of solving a linear integral equation for neutron flux. This integral equation is solved by the method of successive iterations and its uniqueness is demonstrated. Numeric solution to the integral equation by Monte Carlo method consists in finding a functional of the exact solution. For this, a random process is set up and some random variables are proposed. Then it is demonstrated that each of these variables is an unbiased estimator of that functional. (author)

House of Poison: Poisons in the Home.

Science.gov (United States)

Keller, Rosanne

One of a series of instructional materials produced by the Literacy Council of Alaska, this booklet provides information about common household poisons. Using a simplified vocabulary and shorter sentences, it provides statistics concerning accidental poisonings; a list of the places poisons are usually found in the home; steps to make the home…

Poison Ivy Rash

Science.gov (United States)

Poison ivy rash Overview Poison ivy rash is caused by an allergic reaction to an oily resin called urushiol (u-ROO-she-ol). This oil is in the leaves, stems and roots of poison ivy, poison oak and poison sumac. Wash your ...

Dieffenbachia poisoning

Science.gov (United States)

Dumbcane poisoning; Leopard lily poisoning; Tuft root poisoning ... Get the following information: Person's age, weight, and condition Parts of the plant that were eaten, if known Time swallowed Amount swallowed

The good and the bad of poisonous plants: an introduction to the USDA-ARS Poisonous Plant Research Laboratory.

Science.gov (United States)

Welch, Kevin D; Panter, Kip E; Gardner, Dale R; Stegelmeier, Bryan L

2012-06-01

This article provides an overview of the Poisonous Plant Research Laboratory (PPRL), about the unique services and activities of the PPRL and the potential assistance that they can provide to plant poisoning incidences. The PPRL is a federal research laboratory. It is part of the Agricultural Research Service, the in-house research arm of the U.S. Department of Agriculture. The mission of the PPRL is to identify toxic plants and their toxic compounds, determine how the plants poison animals, and develop diagnostic and prognostic procedures for poisoned animals. Furthermore, the PPRL's mission is to identify the conditions under which poisoning occurs and develop management strategies and treatments to reduce losses. Information obtained through research efforts at the PPRL is mostly used by the livestock industry, natural resource managers, veterinarians, chemists, plant and animal scientists, extension personnel, and other state and federal agencies. PPRL currently has 9 scientists and 17 support staff, representing various disciplines consisting of toxicology, reproductive toxicology, veterinary medicine, chemistry, animal science, range science, and plant physiology. This team of scientists provides an interdisciplinary approach to applied and basic research to develop solutions to plant intoxications. While the mission of the PPRL primarily impacts the livestock industry, spinoff benefits such as development of animal models, isolation and characterization of novel compounds, elucidation of biological and molecular mechanisms of action, national and international collaborations, and outreach efforts are significant to biomedical researchers. The staff at the PPRL has extensive knowledge regarding a number of poisonous plants. Although the focus of their knowledge is on plants that affect livestock, oftentimes, these plants are also poisonous to humans, and thus, similar principles could apply for cases of human poisonings. Consequently, the information provided

Neutron diffraction radiation of solid solution of carbon and hydrogen in the α-titanium in the homogeneity domain

International Nuclear Information System (INIS)

Mirzaev, B.B.; Khidirov, I.; Mukhtarova, N.N.

2005-01-01

In the work by the neutron-graph the homogeneity domain of the introduction solid solution TiC x H y is determined. The sample neutron grams have been taken on the neutron diffractometer (λ=.1085 nm) installed at the thermal column of the WWR-SM reactor (INF AN RUz). For the phase analysis and estimation of solid solutions homogeneity the X-ray graph was used. X-ray grams were taken on the X-ray diffractometer DRON-3M with use of CuK α radiation (λ=0.015418 nm)

Preliminary Experiment on Neutron-Induced Mn Activity in Mn-Cd Solutions

Energy Technology Data Exchange (ETDEWEB)

Broda, E.

1942-07-01

This report was written by E. Broda, J. Gueron and L. Kowarski at the Cavendish Laboratory (Cambridge) in June 1942 and is about a preliminary experiment on neutron-induced Mn activity in Mn-Cd solutions. The description of the experiment and the results can be found also in this report. (nowak)

Fast solution of neutron diffusion problem by reduced basis finite element method

International Nuclear Information System (INIS)

Chunyu, Zhang; Gong, Chen

2018-01-01

Highlights: •An extremely efficient method is proposed to solve the neutron diffusion equation with varying the cross sections. •Three orders of speedup is achieved for IAEA benchmark problems. •The method may open a new possibility of efficient high-fidelity modeling of large scale problems in nuclear engineering. -- Abstract: For the important applications which need carry out many times of neutron diffusion calculations such as the fuel depletion analysis and the neutronics-thermohydraulics coupling analysis, fast and accurate solutions of the neutron diffusion equation are demanding but necessary. In the present work, the certified reduced basis finite element method is proposed and implemented to solve the generalized eigenvalue problems of neutron diffusion with variable cross sections. The order reduced model is built upon high-fidelity finite element approximations during the offline stage. During the online stage, both the k eff and the spatical distribution of neutron flux can be obtained very efficiently for any given set of cross sections. Numerical tests show that a speedup of around 1100 is achieved for the IAEA two-dimensional PWR benchmark problem and a speedup of around 3400 is achieved for the three-dimensional counterpart with the fission cross-sections, the absorption cross-sections and the scattering cross-sections treated as parameters.

Mistletoe poisoning

Science.gov (United States)

... if known Time it was swallowed Amount swallowed Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

Detergent poisoning

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... if known) Time it was swallowed Amount swallowed Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

Kerosene poisoning

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... if known) Time it was swallowed Amount swallowed Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

Zinc poisoning

Science.gov (United States)

... help if this information is not immediately available. Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

Foxglove poisoning

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... if known Time it was swallowed Amount swallowed Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

Cologne poisoning

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... the product Time it was swallowed Amount swallowed Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

Oleander poisoning

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... if known Time it was swallowed Amount swallowed Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

Ammonia poisoning

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... if known) Time it was swallowed Amount swallowed Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

Yew poisoning

Science.gov (United States)

... if known Time it was swallowed Amount swallowed Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

Philodendron poisoning

Science.gov (United States)

... if known Time it was swallowed Amount swallowed Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

Bee poison

Science.gov (United States)

... page: //medlineplus.gov/ency/article/002847.htm Bee poison To use the sharing features on this page, ... Time of the sting Location of the sting Poison Control Your local poison center can be reached ...

Insecticide poisoning

Science.gov (United States)

... if known) Time it was swallowed Amount swallowed Poison Control Your local poison control center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

Neutron absorption profile in a reactor moderated by different mixtures of light and heavy waters

International Nuclear Information System (INIS)

Nagy, Mohamed E.; Aly, Mohamed N.; Gaber, Fatma A.; Dorrah, Mahmoud E.

2014-01-01

Highlights: • We studied neutron absorption spectra in a mixed water moderated reactor. • Changing D 2 O% in moderator induced neutron energy spectral shift. • Most of the neutrons absorbed in control rods were epithermal. • Control rods worth changes were not proportional to changes of D 2 O% in moderator. • Control rod arrangement influenced the neutronic behavior of the reactor. - Abstract: A Monte-Carlo parametric study was carried out to investigate the neutron absorption profile in a model of LR-0 reactor when it is moderated by different mixtures of heavy/light waters at molecular ratios ranging from 0% up to 100% D 2 O at increments of 10% in D 2 O. The tallies included; neutron absorption profiles in control rods and moderator, and neutron capture profile in 238 U. The work focused on neutron absorption in control rods entailing; total mass of control rods needed to attain criticality, neutron absorption density and total neutron absorption in control rods at each of the studied mixed water moderators. The aim was to explore whether thermal neutron poisons are the most suitable poisons to be used in control rods of nuclear reactors moderated by mixed heavy/light water moderators

Solution Synthesis and Processing of PZT Materials for Neutron Generator Applications

Energy Technology Data Exchange (ETDEWEB)

Anderson, M.A.; Ewsuk, K.G.; Montoya, T.V.; Moore, R.H.; Sipola, D.L.; Tuttle, B.A.; Voigt, J.A.

1998-12-01

A new solution synthesis route has been developed for the preparation of lead-based ferroelectric materials (patent filed). The process produces controlled stoichiometry precursor powders by non-aqueous precipitation. For a given ferroelectric material to be prepared, a metal acetate/alkoxide solution containing constituent metal species in the appropriate ratio is mixed with an oxalic acid/n-propanol precipitant solution. An oxalate coprecipitate is instantly fonned upon mixing that quantitatively removes the metals from solution. Most of the process development was focused on the synthesis and processing of niobium-substituted lead zirconate titanate with a Zr-to-Ti ratio of 95:5 (PNZT 95/5) that has an application in neutron generator power supplies. The process was scaled to produce 1.6 kg of the PNZT 95/5 powder using either a sen-ii-batch or a continuous precipitation scheme. Several of the PNZT 95/5 powder lots were processed into ceramic slug form. The slugs in turn were processed into components and characterized. The physical properties and electrical performance (including explosive functional testing of the components met the requirements set for the neutron generator application. Also, it has been demonstrated that the process is highly reproducible with respect to the properties of the powders it produces and the properties of the ceramics prepared from its powders. The work described in this report was funded by Sandia's Laboratory Directed Research and Development Program.

On the exact solution for the multi-group kinetic neutron diffusion equation in a rectangle

International Nuclear Information System (INIS)

Petersen, C.Z.; Vilhena, M.T.M.B. de; Bodmann, B.E.J.

2011-01-01

In this work we consider the two-group bi-dimensional kinetic neutron diffusion equation. The solution procedure formalism is general with respect to the number of energy groups, neutron precursor families and regions with different chemical compositions. The fast and thermal flux and the delayed neutron precursor yields are expanded in a truncated double series in terms of eigenfunctions that, upon insertion into the kinetic equation and upon taking moments, results in a first order linear differential matrix equation with source terms. We split the matrix appearing in the transformed problem into a sum of a diagonal matrix plus the matrix containing the remaining terms and recast the transformed problem into a form that can be solved in the spirit of Adomian's recursive decomposition formalism. Convergence of the solution is guaranteed by the Cardinal Interpolation Theorem. We give numerical simulations and comparisons with available results in the literature. (author)

Quasielastic scattering of slow-neutron in water-alcohol solutions

Directory of Open Access Journals (Sweden)

N. O. Atamas

2010-06-01

Full Text Available Research of molecules dynamics of solutions “water - propyl alcohol” of different concentration at the temperature 281 K is conducted by the method of slow-neutron quasi-elastic scattering. There were experimentally exposed the feature of effective self-diffusion coefficient of molecules of the indicated solutions. Based on the time- scale hierarchy the division of selfdiffusion coefficient to one-particle and collective contributions was conducted, and the time of the molecules settled life in position of equilibrium was calculated. There were also exposed the feature of self-diffusion concentration dependence of coefficient of self-diffusion and his selfpart contribution, namely: presence of two minimums is in the areas of concentrations (0,04 ÷ 0,05 of mass fraction and (0,18 ÷ 0,22 m.c. of the alcohol and continuous character of diffusion at concentrations higher then 0,4 m.c. of the alcohol. It is shown that the indicated concentration areas correspond the certain local structures of investigational solution.

Quadrature with arbitrary weight for the numerical solution of the critical slab Neutron Transport Equation

International Nuclear Information System (INIS)

Sanchez G, J.

2007-01-01

A standard procedure for the solution of singular integral equations is applied to the one-dimensional transport equation for monoenergetic neutrons. The results obtained with two versions of the procedure, differing only in the extent of the basic region to which they are applied, are compared with analytically derived results available for benchmarking. The procedures considered yield consistent results for the calculated neutron densities and eigenvalues. Several approximate expressions of the neutron density are used to render closed-form formulas for the densities which can then be analytically operated on to obtain expressions for extrapolation distances or angular densities or serve other purposes that require an analytical expression of the neutron density. (Author)

Matching of analytical and numerical solutions for neutron stars of arbitrary rotation

International Nuclear Information System (INIS)

Pappas, George

2009-01-01

We demonstrate the results of an attempt to match the two-soliton analytical solution with the numerically produced solutions of the Einstein field equations, that describe the spacetime exterior of rotating neutron stars, for arbitrary rotation. The matching procedure is performed by equating the first four multipole moments of the analytical solution to the multipole moments of the numerical one. We then argue that in order to check the effectiveness of the matching of the analytical with the numerical solution we should compare the metric components, the radius of the innermost stable circular orbit (R ISCO ), the rotation frequency and the epicyclic frequencies Ω ρ , Ω z . Finally we present some results of the comparison.

Matching of analytical and numerical solutions for neutron stars of arbitrary rotation

Energy Technology Data Exchange (ETDEWEB)

Pappas, George, E-mail: gpappas@phys.uoa.g [Section of Astrophysics, Astronomy, and Mechanics, Department of Physics, University of Athens, Panepistimiopolis Zografos GR15783, Athens (Greece)

2009-10-01

We demonstrate the results of an attempt to match the two-soliton analytical solution with the numerically produced solutions of the Einstein field equations, that describe the spacetime exterior of rotating neutron stars, for arbitrary rotation. The matching procedure is performed by equating the first four multipole moments of the analytical solution to the multipole moments of the numerical one. We then argue that in order to check the effectiveness of the matching of the analytical with the numerical solution we should compare the metric components, the radius of the innermost stable circular orbit (R{sub ISCO}), the rotation frequency and the epicyclic frequencies {Omega}{sub {rho}}, {Omega}{sub z}. Finally we present some results of the comparison.

Structure of fullerene aggregates in pyridine/water solutions by small-angle neutron scattering

International Nuclear Information System (INIS)

Aksenov, V.L.; Belushkin, A.V.; Avdeev, M.V.; Rosta, L.; Mihailovic, D.; Mrzel, A.; Serdyuk, I.N.; Timchenko, A.A.

2001-01-01

Results of small-angle neutron scattering experiments on fullerenes (C 60 ) in pyridine/water solutions are reported. They confirm conclusions of the previous studies, in particular, dynamic light scattering experiments. Aggregates with characteristic radius of about 20 nm are formed in the solutions. The contrast variation using different combinations of protonated/deuterated components (water and pyridine) of the solutions points to the small pyridine content inside the aggregates. This fact testifies that the aggregates consist of a massive fullerene core covered by a thin pyridine shell

Molecular Dynamics and Neutron Scattering Studies of Mixed Solutions of Caffeine and Pyridine in Water.

Science.gov (United States)

Tavagnacco, Letizia; Mason, Philip E; Neilson, George W; Saboungi, Marie-Louise; Cesàro, Attilio; Brady, John W

2018-05-31

Insight into the molecular interactions of homotactic and heterotactic association of caffeine and pyridine in aqueous solution is given on the basis of both experimental and simulation studies. Caffeine is about 5 times more soluble in a 3 m aqueous pyridine solution than it is in pure water (an increase from ∼0.1 m to 0.5 m). At this elevated concentration the system becomes suitable for neutron scattering study. Caffeine-pyridine interactions were studied by neutron scattering and molecular dynamics simulations, allowing a detailed characterization of the spatial and orientational structure of the solution. It was found that while pyridine-caffeine interactions are not as strong as caffeine-caffeine interactions, the pyridine-caffeine interactions still significantly disrupted caffeine-caffeine stacking. The alteration of the caffeine-caffeine stacking, occasioned by the presence of pyridine molecules in solution and the consequent formation of heterotactic interactions, leads to the experimentally detected increase in caffeine solubility.

An analytical solution of the one-dimensional neutron diffusion kinetic equation in cartesian geometry

International Nuclear Information System (INIS)

Ceolin, Celina; Vilhena, Marco T.; Petersen, Claudio Z.

2009-01-01

In this work we report an analytical solution for the monoenergetic neutron diffusion kinetic equation in cartesian geometry. Bearing in mind that the equation for the delayed neutron precursor concentration is a first order linear differential equation in the time variable, to make possible the application of the GITT approach to the kinetic equation, we introduce a fictitious diffusion term multiplied by a positive small value ε. By this procedure, we are able to solve this set of equations. Indeed, applying the GITT technique to the modified diffusion kinetic equation, we come out with a matrix differential equation which has a well known analytical solution when ε goes to zero. We report numerical simulations as well study of numerical convergence of the results attained. (author)

Neutron thermalization in light water

International Nuclear Information System (INIS)

Abbate, M.J.; Lolich, J.V.

1975-05-01

Investigations related to neutron thermalization in light water have been made. Neutron spectra under quasi-infinite-medium conditions have been measured by the time-of-flight technique and calculations were performed with different codes. Through the use of improved experimental techniques and the best known calculational techniques available, the known discrepancies between experimentals and theoretical values were below from 40% to 16%. The present disagreement is believed to be due the scattering model used (ENDF-GASKET, based on the modified Haywood II frequency spectra), that shows to be very satisfactory for poisoned light water cases. Moreover, previous experiments were completed and differential, integral and pulse-source experimental techniques were improved. Also a second step of a neutron and reactor calculation system was completed. (author)

Scombroid fish poisoning: an overlooked marine food poisoning.

Science.gov (United States)

Wu, M L; Yang, C C; Yang, G Y; Ger, J; Deng, J F

1997-08-01

Scombroid fish poisoning is a food-borne chemical intoxication caused by certain spoiled fish that contain a large amount of histamine and some biogenic diamines. It has gradually become a world-wide medical problem and probably is the most common cause of fish poisoning. As the data on the incidents of scombroid fish poisoning in Taiwan remains scarce, we report 2 incidents of scombroid fish poisoning in Northern Taiwan. We collected data of the 2 outbreaks of suspected fish poisoning which were reported to us in 1996. An epidemiological investigation was undertaken. Questionnaire interviews were given to persons who ate lunch in the same cafeteria in outbreak 2. The leftover fish were sent for species identification and toxin analysis. The first incident involving 4 women occurred in March 1996. All cases experienced flush, dizziness, blurred vision and skin rashes after eating lunch. A non-scombroid fish of Makaira with histamine levels as high as 84.13 mg/100 g flesh was implicated in this incident. In August 1996, another incident involving some cases who ate lunch at the same cafeteria were investigated. A total of 146 questionnaires were distributed with a return of 132 questionnaires (90.4%). Fifty-five employees reported positive signs or symptoms; 48 persons who ate fish and 7 women who did not eat fish were ill. Fish was the only food associated with the illness with an attack rate of 73.8% (p < 0.001). The incriminated fish was later identified as a scombroid fish of Euthynnus with a histamine content of 271.9 mg/100 g flesh in 1 leftover piece and 118.5 mg/100 g flesh in another piece. Most cases in these 2 outbreaks received treatment with antihistamines and had rapid and complete recovery. The diagnosis of scombroid fish poisoning could be misdiagnosed as food allergy or bacterial food poisoning if physicians are not aware of such poisoning. The nonspecific but characteristic symptomatology of histamine food poisoning and previous consumption of fish

Small angle neutron scattering study of the gemini nonionic surfactant in heavy water solutions

International Nuclear Information System (INIS)

Rajewska, A

2012-01-01

The nonionic gemini surfactant α α'-[2,4,7,9-tetramethyl-5-decyne-4,7diyl]bis[ω hydroxyl-polyoxyethylene] (S-10) was investigated in heavy water solutions only for concentrations: 2.3%, 2.5%,3%, 3.4%, 4% and 5% at temperature 25 C with small angle neutron scattering (SANS) method. All of surfactants solutions were prepared using D 2 O (99.9% deuterated, Prikladnaia Chimia, St. Petersburg, Russia) as a solvent. The nonionic gemini surfactant S-10 was obtained from Air Products and Chemicals, Inc., and used without further purification. All SANS measurements were performed on V-4 SANS spectrometer at BENSC, Berlin (Germany). Neutrons were used in wavelength range of 0.02 - 4 nm - 1. For the measurements quartz cells of were used during experiment. Up to 14 such cells were placed in a holder. Results from experiment was calculated and evaluated with PCG 2.0 program from Graz University (Austria). In the investigated solutions two axis ellipsoidal micelles was observed.

Poisoning

Science.gov (United States)

... your home. Regularly test and replace the batteries. Poisoning treatment Treatment depends on the person and the type ... Injury Prevention, Prevention and Wellness, Staying HealthyTags: chemical ... poison treatments, snakebite, syrup of ipecac July 12, 2017 Featured ...

Measurement of low neutron fluences with polycarbonate foils electrochemically etched with methyl alcohol-KOH solution

International Nuclear Information System (INIS)

Kumamoto, Y.

1982-01-01

Electrochemical etching of polycarbonate foils was performed using a KOH solution with a high concentration of methyl alcohol under different conditions of field strength, frequency, temperature and etching time. These studies showed that the highest neutron sensitivity relative to the inherent background in the foil was obtained under the following etching conditions: 52 kV/cm, 1 kHz, 30 0 C, 30 min in a solution of 45 gm KOH + 80 cc CH 3 OH + 20 cc H 2 O. Under these conditions, 100 mrem of neutrons from a Ra-Be source gave 70 pits per cm 2 while background was 7 +- 3 pits per cm 2 (10 +- 5 mrem). The pit diameters were about 90 μm. This sensitivity (giving lowest measurable dose of 15 mrem) is quite sufficient for personnel neutron dosimetry applications and the size of the pits is large enough for easy counting using a microscope at magnification of 40X. (author)

Thermal neutron absorption cross-section for small samples (experiments in cylindrical geometry)

International Nuclear Information System (INIS)

Czubek, J.A.; Drozdowicz, K.; Igielski, A.; Krynicka-Drozdowicz, E.; Woznicka, U.

1982-01-01

Measurement results for thermal neutron macroscopic absorption cross-sections Σsub(a)1 when applying the cylindrical sample-moderator system are presented. Experiments for liquid (water solutions of H 3 BO 3 ) and solid (crushed basalts) samples are reported. Solid samples have been saturated with the H 3 BO 3 ''poisoning'' solution. The accuracy obtained for the determination of the absorption cross-section of the solid material was σ(Σsub(ma))=(1.2+2.2) c.u. in the case when porosity was measured with the accuracy of σ(phi)=0.001+0.002. The dispersion of the Σsub(ma) data obtained for basalts (taken from different quarries) was higher than the accuracy of the measurement. All experimental data for the fundamental decay constants lambda 0 together with the whole information about the samples are given. (author)

Solution of the multigroup neutron diffusion Eigenvalue problem in slab geometry by modified power method

Energy Technology Data Exchange (ETDEWEB)

Zanette, Rodrigo [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Programa de Pós-Graduação em Matemática Aplicada; Petersen, Claudio Z.; Tavares, Matheus G., E-mail: rodrigozanette@hotmail.com, E-mail: claudiopetersen@yahoo.com.br, E-mail: matheus.gulartetavares@gmail.com [Universidade Federal de Pelotas (UFPEL), RS (Brazil). Programa de Pós-Graduação em Modelagem Matemática

2017-07-01

We describe in this work the application of the modified power method for solve the multigroup neutron diffusion eigenvalue problem in slab geometry considering two-dimensions for nuclear reactor global calculations. It is well known that criticality calculations can often be best approached by solving eigenvalue problems. The criticality in nuclear reactors physics plays a relevant role since establishes the ratio between the numbers of neutrons generated in successive fission reactions. In order to solve the eigenvalue problem, a modified power method is used to obtain the dominant eigenvalue (effective multiplication factor (K{sub eff})) and its corresponding eigenfunction (scalar neutron flux), which is non-negative in every domain, that is, physically relevant. The innovation of this work is solving the neutron diffusion equation in analytical form for each new iteration of the power method. For solve this problem we propose to apply the Finite Fourier Sine Transform on one of the spatial variables obtaining a transformed problem which is resolved by well-established methods for ordinary differential equations. The inverse Fourier transform is used to reconstruct the solution for the original problem. It is known that the power method is an iterative source method in which is updated by the neutron flux expression of previous iteration. Thus, for each new iteration, the neutron flux expression becomes larger and more complex due to analytical solution what makes propose that it be reconstructed through an polynomial interpolation. The methodology is implemented to solve a homogeneous problem and the results are compared with works presents in the literature. (author)

Neutron transport. Physics and calculation of nuclear reactors with applications to pressurized water reactors and fast neutron reactors. 2 ed.

International Nuclear Information System (INIS)

Bussac, J.; Reuss, P.

1985-01-01

This book presents the main physical bases of neutron theory and nuclear reactor calculation. 1) Interactions of neutrons with matter and basic principles of neutron transport; 2) Neutron transport in homogeneous medium and the neutron field: kinetic behaviour, slowing-down, resonance absorption, diffusion equation, processing methods; 3) Theory of a reactor constituted with homogeneous zones: critical condition, kinetics, separation of variables, calculation and neutron balance of the fundamental mode, one-group and multigroup theories; 4) Study of heterogeneous cell lattices: fast fission factor, resonance absorption, thermal output factor, diffusion coefficient, computer codes; 5) Operation and control of reactors: perturbation theory, reactivity, fuel properties evolution, poisoning by fission products, calculation of a reactor and fuel management; 6) Study of some types of reactors: PWR and fast breeder reactors, the main reactor types of the present French program [fr

Preliminary Formulation of Finite Element Solution for the 1-D, 1-G Time Dependent Neutron Diffusion Equation without Consideration about Delay Neutron

Energy Technology Data Exchange (ETDEWEB)

Ryu, Eun Hyun; Song, Yong Mann; Park, Joo Hwan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2013-05-15

If time-dependent equation is solved with the FEM, the limitation of the input geometry will disappear. It has often been pointed out that the numerical methods implemented in the RFSP code are not state-of-the-art. Although an acceleration method such as the Coarse Mesh Finite Difference (CMFD) for Finite Difference Method (FDM) does not exist for the FEM, one should keep in mind that the number of time steps for the transient simulation is not large. The rigorous formulation in this study will richen the theoretical basis of the FEM and lead to an extension of the dynamics code to deal with a more complicated problem. In this study, the formulation for the 1-D, 1-G Time Dependent Neutron Diffusion Equation (TDNDE) without consideration of the delay neutron will first be done. A problem including one multiplying medium will be solved. Also several conclusions from a comparison between the numerical and analytic solutions, a comparison between solutions with various element orders, and a comparison between solutions with different time differencing will be made to be certain about the formulation and FEM solution. By investigating various cases with different values of albedo, theta, and the order of elements, it can be concluded that the finite element solution is agree well with the analytic solution. The higher the element order used, the higher the accuracy improvements are obtained.

Neutronic-thermohydraulic oscillatory instability in modern PWRs due to high concentrations of boron in the water

International Nuclear Information System (INIS)

Novelli, A.

1985-01-01

Conspicuous amounts of boric acid are normally dissolved into the moderator of a modern PWR, especially in BOL operative conditions. If the concentration of such a neutronic poison attains certain limits, the nuclear temperature coefficient of the moderator, which is highly negative in the absence of boron, may turn about and reach positive values, due to the strong thermal expansion of the water. A dynamical model of a PWR system is presented, facilitating a quick stability analysis related to the co-ordination of boric acid solution in the water and control-rod insertion in the core. (author)

Substitution of the soluble boron reactivity control system of a pressurized water reactor by gadolinium burnable poisons

International Nuclear Information System (INIS)

Galperin, A.; Segev, M.; Radkowsky, A.

1986-01-01

The results are presented of a research project that is aimed at designing a gadolinium burnable poison (BP) system for complete reactivity control of a pressurized water reactor (PWR) core during the ''equilibrium'' cycle, resulting in the elimination of the soluble boron system, which represents a considerable saving in both capital and operating costs. A flat and strong negative moderator temperature coefficient is assured for a poison-free moderator. The design analysis of a core, heavily loaded with gadolinium BP rods, was based on a BGUCORE neutronic package and cluster model of a fuel assembly. The project objective was achieved by a novel lumped BP rod, designed as an annulus of gadolinium, clad by zirconium, and inserted into vacant guide thimbles of fresh-fuel assemblies. Specific combinations were found for the inner/outer radii of the poison ring, gadolinium densities, and number of rods per assembly, resulting in an almost flat criticality curve during the cycle. A reactivity swing of ≅1% ΔK can be easily controlled by an existing system of control rods. Comparison of the fuel cycle length of a gadolinium-controlled core with that of the reference, soluble, boron-controlled core indicated that there is no penalty due to residual poison at end of life. Unique guidelines for the fuel loading strategy were applied to find a practical fuel-shuffling scheme by which the design and operational constraints of a typical PWR core of current design were satisfied. Several problems should be solved for a practical implementation of the presented design relative to operational and safety requirements of the existing control rod system. Adequate movement of the regulating rods should be determined and shutdown margins of the safety rods should be ascertained. Final judgment of the feasibility of the concept may be made following the solution of these and other regulatory-related issues

Crystal structure solution of hydrides containing natEu from neutron powder diffraction data

International Nuclear Information System (INIS)

Kohlmann, H.

1999-01-01

Complete text of publication follows. The location of hydrogen in crystal structures of metal hydrides usually requires neutron diffraction data. Some elements, however, show excessively high absorption cross sections, σ a , for neutrons, thus making this technique seemingly impractical. Therefore no complete, refined crystal structure data of europium hydrides (σ a ( nat Eu) = .4530 barns at λ = 179.8 pm [1]) have been reported so far. It is shown that the absorption can be reduced to a value reasonable for neutron diffraction experiments by taking advantage of the wavelength dependence of σ a combined with the use of annular samples at advanced diffractometers. Neutron powder diffraction data on several nat Eu containing deuterides suitable for the ab initio crystal structure solution and refinement have been taken at D20 and D4 (ILL, Grenoble). The crystal chemistry of these europium hydrides, among them the two new compounds EuMg 2 H 6 and EuMgH 4 [2], is discussed. (author) [1] V.F. Sears, Neutron News 1992, 3, 26-37.; [2] H. Kohlmann, F. Gingl, T. Hansen, K. Yvon, Angew. Chem. Int. Ed. Eng. 1999, 38, accepted

Poisoning - fish and shellfish

Science.gov (United States)

Fish poisoning; Dinoflagellate poisoning; Seafood contamination; Paralytic shellfish poisoning; Ciguatera poisoning ... algae and algae-like organisms called dinoflagellates. Small fish that eat the algae become contaminated. If larger ...

Solutions of Boltzmann`s Equation for Mono-energetic Neutrons in an Infinite Homogeneous Medium

Science.gov (United States)

Wigner, E. P.

1943-11-30

Boltzman's equation is solved for the case of monoenergetic neutrons created by a plane or point source in an infinite medium which has spherically symmetric scattering. The customary solution of the diffusion equation appears to be multiplied by a constant factor which is smaller than 1. In addition to this term the total neutron density contains another term which is important in the neighborhood of the source. It varies as 1/r{sup 2} in the neighborhood of a point source. (auth)

Bug spray poisoning

Science.gov (United States)

... was swallowed or inhaled Amount swallowed or inhaled Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

Burnable neutron absorbers

International Nuclear Information System (INIS)

Radford, K.C.; Carlson, W.G.

1983-01-01

A neutron-absorber body for use in burnable poison rods in a nuclear reactor. The body is composed of a matrix of Al 2 O 3 containing B 4 C, the neutron absorber. Areas of high density polycrystalline Al 2 O 3 particles are predominantly encircled by pores in some of which there are B 4 C particles. This body is produced by initially spray drying a slurry of A1 2 O 3 powder to which a binder has been added. The powder of agglomerated spheres of the A1 2 O 3 with the binder are dry mixed with B 4 C powder. The mixed powder is formed into a green body by isostatic pressure and the green body is sintered. The sintered body is processed to form the neutron-absorber body. In this case the B 4 C particles are separate from the spheres resulting from the spray drying instead of being embedded in the sphere

Managing the reactivity excess of the gas turbine-modular helium reactor by burnable poison and control rods

International Nuclear Information System (INIS)

Talamo, Alberto

2006-01-01

The gas turbine-modular helium reactor coupled to the deep burn in-core fuel management strategy offers the extraordinary capability to incinerate over 50% of the initial inventory of fissile material. This extraordinary feature, coming from an advanced and well tested fuel element design, which takes advantage of the TRISO particles technology, is maintained while the reactor is loaded with the most different types of fuels. In the present work, we assumed the reactor operating at the equilibrium of the fuel composition, obtained by a 6 years irradiation of light water reactor waste, and we investigated the effects of the introduction of the burnable poison and the control rods; we equipped the core with all the three types of control rods: operational, startup and shutdown ones. We employed as burnable poison natural erbium, due to the 167 Er increasing neutron capture microscopic cross-section in the energy range where the neutron spectrum exhibits the thermal peak; in addition, we utilized boron carbide, with 90% enrichment in 1 B, as the absorption material of the control rods. Concerning the burnable poison studies, we focused on the k eff value, the 167 Er mass during burnup, the influence of modifying the radius of the BISO particles kernel and the fuel and moderator coefficients of temperature. Concerning the control rods studies, we investigated the reactivity worth, the changes in the neutron flux profile due to a partial insertion, the influence of modifying the radius of the BISO particles kernel and the β eff , at the beginning of the operation

Managing the reactivity excess of the gas turbine-modular helium reactor by burnable poison and control rods

Energy Technology Data Exchange (ETDEWEB)

Talamo, Alberto [Department of Nuclear and Reactor Physics, Royal Institute of Technology, Roslagstullsbacken 21, S-10691, Stockholm (Sweden)]. E-mail: alby@neutron.kth.se

2006-01-15

The gas turbine-modular helium reactor coupled to the deep burn in-core fuel management strategy offers the extraordinary capability to incinerate over 50% of the initial inventory of fissile material. This extraordinary feature, coming from an advanced and well tested fuel element design, which takes advantage of the TRISO particles technology, is maintained while the reactor is loaded with the most different types of fuels. In the present work, we assumed the reactor operating at the equilibrium of the fuel composition, obtained by a 6 years irradiation of light water reactor waste, and we investigated the effects of the introduction of the burnable poison and the control rods; we equipped the core with all the three types of control rods: operational, startup and shutdown ones. We employed as burnable poison natural erbium, due to the {sup 167}Er increasing neutron capture microscopic cross-section in the energy range where the neutron spectrum exhibits the thermal peak; in addition, we utilized boron carbide, with 90% enrichment in {sup 1}B, as the absorption material of the control rods. Concerning the burnable poison studies, we focused on the k {sub eff} value, the {sup 167}Er mass during burnup, the influence of modifying the radius of the BISO particles kernel and the fuel and moderator coefficients of temperature. Concerning the control rods studies, we investigated the reactivity worth, the changes in the neutron flux profile due to a partial insertion, the influence of modifying the radius of the BISO particles kernel and the {beta} {sub eff}, at the beginning of the operation.

Poison Control Centers

Science.gov (United States)

... 1222 immediately. Name State American Association of Poison Control Centers Address AAPCC Central Office NOT A POISON ... not for emergency use. Arkansas ASPCA Animal Poison Control Center Address 1717 S. Philo Road, Suite 36 Urbana, ...

Finite element based composite solution for neutron transport problems

International Nuclear Information System (INIS)

Mirza, A.N.; Mirza, N.M.

1995-01-01

A finite element treatment for solving neutron transport problems is presented. The employs region-wise discontinuous finite elements for the spatial representation of the neutron angular flux, while spherical harmonics are used for directional dependence. Composite solutions has been obtained by using different orders of angular approximations in different parts of a system. The method has been successfully implemented for one dimensional slab and two dimensional rectangular geometry problems. An overall reduction in the number of nodal coefficients (more than 60% in some cases as compared to conventional schemes) has been achieved without loss of accuracy with better utilization of computational resources. The method also provides an efficient way of handling physically difficult situations such as treatment of voids in duct problems and sharply changing angular flux. It is observed that a great wealth of information about the spatial and directional dependence of the angular flux is obtained much more quickly as compared to Monte Carlo method, where most of the information in restricted to the locality of immediate interest. (author)

Development of liquid poison injection system (SDS-2) for 500 MWe PHWRs

International Nuclear Information System (INIS)

Nawathe, Shirish; Umashankari, P.; Balakrishnan, Kamala; Mahajan, S.C.; Kakodkar, A.

1991-01-01

A secondary shut-down system (SDS-2) in the form of a mecahnism for introducing poison into the moderator of the PHWR is under development in Reactor Engineering Division of BARC. The system, as conceived, consists of a tank containing pressurised helium connected to poison tanks through quick opening solenoid valves. The tanks are connected to horizontal injection tubes in the calandria. On system actuation, gadolinium nitrate solution from the tanks passes to the injection tubes which have a number of holes through which the poison enters the moderator. This report details the development work being done on this poison injection system. An experimental facility was set up to measure the poison jet growth rate and the jet spread after injection, and mathematical models were developed to convert the observed jets into reactivity worth values. A description of the work and the computed results are presented. (author). 21 graphs. , 15 tabs

Determination of 2,4-D in aqueous solution by neutron activation analysis

International Nuclear Information System (INIS)

Martinez-Miranda, V.; Esteller, M.V.

1999-01-01

A method based on neutron activation analysis was developed for the determination of fractions of milligrams of 2,4-D (2,4-dichlorophenoxy acetic acid) in aqueous solution in laboratory tests. The indirect determination of 2,4-D was based on the quantification of chlorine, 38 Cl, produced by neutron activation. The range of application was 0.01 - 100 mg x l -1 . No loss of 38 Cl by chemical effects of the nuclear reaction was found. The advantages of the proposed method include high precision and sensitivity of determination. Results were compared with those obtained by UV-Vis spectrophotometry, where concentrations less than 1 mg x l -1 were not detected. (author)

Neutron dosimetry program at Mound - problems and solutions

International Nuclear Information System (INIS)

Winegardner, M.K.

1991-01-01

The Mound personnel neutron dosimetry program utilizes TLD albedo technology. The neutron dosimeter design incorporates a two-element spectrometer for site-specific neutron quality determination and empirical application of field neutron calibration factors. Design elements feature two Li(6)F (TLD- 600) chips for neutron detection and one Li(7)F (TLD-700) chip for gamma compensation of the TLD- 600 chips. One TLD-600 chip is Cadmium shielded on the front side of the dosimeter, the other is Cadmium shielded from the back side. Tin filters are placed opposite of the Cadmium shield on each of the TLD-600 chips and on both sides of the TLD-700 chip for symmetrically equivalent gamma absorption characteristics. Neutron quality determination is accomplished by the albedo neutron-to- incident thermal neutron response ratio above the Cadmium cutoff. This front Cadmium shielded-to-back Cadmium shielded response ratio, compensated for the presence of gamma radiation, provides the basis for neutron energy calibration via the albedo response curve

Analysis of intentional drug poisonings using Ohio Poison Control Center Data, 2002-2014.

Science.gov (United States)

Pringle, Kelsey; Caupp, Sarah; Shi, Junxin; Wheeler, Krista K; Spiller, Henry A; Casavant, Marcel J; Xiang, Henry

2017-08-01

Pharmaceutical drug poisonings, especially those that are intentional, are a serious problem for adolescents and young adults. Poison control center data is a viable tool to track intentional drug poisonings in near real-time. To determine intentional drug poisoning rates among adolescents and young adults in Ohio using poison control center data. We analyzed data from 2002 to 2014 obtained by Ohio's three poison control centers. Inclusion variables were calls made to the centers that had appropriate subject age (10-29 years old), subject sex, involved substance (all drug classes), and medical outcome (no effect, minor effect, moderate effect, major effect, and death). Intentional drug poisoning reports were also separated into subgroups to compare suspected suicide reports to misuse and abuse reports. Finally, resident population estimates were used to generate 2014 intentional drug poisoning rates for each county in Ohio. The most common age group for intentional drug poisonings was 18-24. Females reported more suspected suicide drug poisonings while males reported more misuse/abuse drug poisonings. The most reported drug class across all ages was analgesics. Of the 88 counties in Ohio, Hamilton, Williams, Washington, and Guernsey counties had the highest rates of intentional drug poisonings. The high report rate of suspected suicides and analgesic class drugs demonstrates the need for preventative measures for adolescents and young adults in Ohio. Any interventions, along with legislative changes, will need to take place in our local communities.

Neutron studies of paramagnetic fullerenols’ assembly in aqueous solutions

Science.gov (United States)

Lebedev, V. T.; Szhogina, A. A.; Suyasova, M. V.

2018-03-01

Recent results on structural studies of aqueous solutions of water-soluble derivatives of endofullerenes encapsulating 4f- and 3d-elements have been presented. Neutron small angle scattering experiments allowed recognize subtle features of fullerenols assembly as dependent on chemical nature (atomic number) of interior atom, pH-factor and temperature of solutions. It was observed a fractal-type fullerenols’ ordering at the scale of correlation radii ∼ 10-20 nm when molecules with iron atoms are integrated into branched structures at low concentrations (C ≤ 1 % wt.) and organized into globular aggregates at higher amounts (C > 1 % wt.). On the other hand, for Lanthanides captured in carbon cages the supramolecular structures are mostly globular and have larger gyration radii ∼ 30 nm. They demonstrated a good stability in acidic (pH ∼ 3) and neutral (pH ∼ 7) media that is important for forthcoming medical applications.

Proceedings of the 182nd basic science seminar (The workshop on neutron structural biology ) 'New frontiers of structural biology advanced by solution scattering'

International Nuclear Information System (INIS)

Fujiwara, Satoru

2001-03-01

182nd advanced science seminar (the workshop on neutron structural biology) was held in February 9-10, 2000 at Tokai. Thirty-six participants from universities, research institutes, and private companies took part in the workshop, and total of 24 lectures were given. This proceedings collects abstracts, the figures and tables, which the speakers used in their lectures. The proceedings contains two reviews from the point of view of x-ray and neutron scatterings, and six subjects (21 papers) including neutron and x-ray scattering in the era of structure genomics, structural changes detected with solution scattering, a new way in structural biology opened by neutron crystallography and neutron scattering, x-ray sources and detectors, simulation and solution scattering, and neutron sources and detectors. (Kazumata, Y.)

Development and validation of a model for CANDU-6 SDS2 poison injection analysis

International Nuclear Information System (INIS)

Lee, B. W.; Jung, C. J.; Min, B. J.; Yoon, H. J.; Choi, J. H.; Jang, D. S.

2002-01-01

In CANDU-6 reactor there are two independent reactor shutdown systems. The shutdown system no. 2(SDS2) injects the liquid poison into the moderator tank by high pressure via small holes on the 6 nozzle pipes and stops the nuclear chain reaction. To ensure the safe shutdown of a reactor loaded with either DUPIC or SEU fuels it is necessary for the poison curtains generated by jets provide quick, and enough negative reactivity to the reactor during the early stage of the accident. In order to produce the neutron cross section necessary to perform this work, the poison concentration distribution during the transient is necessary. The motivation for this work arose from the fact that the computer code package for performing this task is not transfered to Korea yet. In this study, a set of models for analyzing the transient poison concentration induced by this high pressure poison injection jet activated upon the reactor trip in a CANDU-6 reactor moderator tank has been developed and used to generate the poison concentration distribution of the poison curtains induced by the high pressure jets injected into the vacant region between the pressure tube banks. The poison injection rate through the jet holes drilled on the nozzle pipes is obtained by a 1-D transient hydrodynamic code called, ALITRIG, and this injection rate is used to provide the inlet boundary condition to a 3-D CFD model of the moderator tank based on CFX4.3, a commercial CFD code developed by AEA technology, to simulate the formation of the poison jet curtain inside the moderator tank. For the validation, a simulation for a generic CANDU-6 SDS2 design poison jet growth experiment was made to evaluate this model's capability against experiment. As no concentration field was measured and only the growth of the poison jet height was obtained by high speed camera, the validation was limited as such. The result showed that if one assume the jet front corresponds to 200 ppm of the poison the model succeed to

Gadolinium for neutron detection in current nuclear instrumentation research: A review

Science.gov (United States)

Dumazert, J.; Coulon, R.; Lecomte, Q.; Bertrand, G. H. V.; Hamel, M.

2018-02-01

Natural gadolinium displays a number of remarkable physical properties: it is a rare earth element, composed of seven stable or quasi-stable isotopes, with an exceptionally high magnetization and a Curie point near room temperature. Its use in the field of nuclear instrumentation historically relates to its efficiency as a neutron poison in power reactors. Gadolinium is indeed the naturally occurring element with the highest interaction probability with neutrons at thermal energy, shared between Gd-157 (15.65%, 254000 b cross section) and Gd-155 (14.8%, 60900 b) isotopes. Considering that neutron capture results in an isotopic change, followed by a radiative rearrangement of nuclear and atomic structures, Gd may be embodied not merely as a neutron poison but as a neutron converter into a prompt photon and an electron source term. Depending on the nature and energy of the reaction products (from a few-keV Auger electrons up to 8 MeV gamma rays) that the detector aims at isolating as an indirect neutron signature, a variety of sensor media and counting methods have been introduced during the last decades. This review first draws a theoretical description of the radiative cascade following Gd(n , γ) capture. The cascade may be subdivided into regions of interest, each corresponding to dedicated detection designs and optimizations whose current status is detailed. This inventory has allowed the authors to extract and benchmark key figures of merit for the definition of a detection scheme: neutron attenuation, neutron sensitivity (cps/nv), gamma rejection, neutron detection limit in a mixed field, intrinsic or extrinsic moderation, and transportability. On this basis, the authors have identified promising paths for Gd-based neutron detection in contemporary instrumentation.

Benzene poisoning

Science.gov (United States)

... may be admitted to the hospital if the poisoning is severe. ... benzene they swallowed and how quickly they receive treatment. The ... Poisoning can cause rapid death. However, deaths have occurred ...

The isolation of lutetium from gadolinium contained in Purex process solutions

International Nuclear Information System (INIS)

Bostick, D.T.; Vick, D.O.; May, M.P.; Walker, R.L.

1992-09-01

A chemical separation procedure has been devised to isolate Lu from Purex dissolver solutions containing the neutron poison, Gd. The isolation procedure involves the removal of U and >Pu from a dissolver solution using tributylphosphate solvent extraction. If required, solvent extraction using di-(2-ethylhexyl) phosphoric acid can be employed to further purify the sample be removing alkali and alkali earth elements. Finally, Lu is chromatographically separated from Gd and rare earth fission products on a Dowex 50W-X8 resin column using an alpha-hydroxyisobutyrate eluant. The success of the chemical separation procedure has been demonstrated in the quantitative recovery of as little as 1.4 ng Lu from solutions containing a 5000-fold excess of Gd. Additionally, Lu has been isolated from synthetic dissolver samples containing U, Ba, Cs, and Gd. Thermal emission MS data indicated that the Lu fraction of the synthetic sample was free of Gd interference

Thermal, thermoelectric, and cathode poisoning effects in cold fusion experiments

International Nuclear Information System (INIS)

Keesing, R.G.; Greenhow, R.C.; Cohler, M.D.; McQuillan, A.J.

1991-01-01

This paper reports on an unsuccessful attempt to repeat the observations by Fleischmann and Pons of cold nuclear fusion in deuterium-charged palladium; no excess heat is found, nor is any gamma or neutron activity identified. Peltier heating at the palladium/platinum junction is investigated, but no effects are seen; the possibility remains, however, that a large Peltier coefficient may arise for deuterium concentrations that render the palladium-deuterium semiconducting. Finally, the effects of poisoning the palladium with cyanide were investigated

Malathion poisoning

Science.gov (United States)

... Prolonged treatment often is needed to reverse the poisoning. This may include staying in the hospital intensive care unit and getting long-term therapy. Some effects of the poison may last for ...

Diazinon poisoning

Science.gov (United States)

... Prolonged treatment often is needed to reverse the poisoning. This may include staying in the hospital intensive care unit and getting long-term therapy. Some effects of the poison may last for ...

The solution of the multigroup neutron transport equation using spherical harmonics

International Nuclear Information System (INIS)

Fletcher, K.

1981-01-01

A solution of the multi-group neutron transport equation in up to three space dimensions is presented. The flux is expanded in a series of unnormalised spherical harmonics. Using the various recurrence formulae a linked set of first order differential equations is obtained for the moments psisup(g)sub(lm)(r), γsup(g)sub(lm)(r). Terms with odd l are eliminated resulting in a second order system which is solved by two methods. The first is a finite difference formulation using an iterative procedure, secondly, in XYZ and XY geometry a finite element solution is given. Results for a test problem using both methods are exhibited and compared. (orig./RW) [de

Solution of two group neutron diffusion equation by using homotopy analysis method

International Nuclear Information System (INIS)

Cavdar, S.

2010-01-01

The Homotopy Analysis Method (HAM), proposed in 1992 by Shi Jun Liao and has been developed since then, is based on differential geometry as well as homotopy which is a fundamental concept in topology. It has proved to be useful for obtaining series solutions of many such problems involving algebraic, linear/non-linear, ordinary/partial differential equations, differential-integral equations, differential-difference equations, and coupled equations of them. Briefly, through HAM, it is possible to construct a continuous mapping of an initial guess approximation to the exact solution of the equation of concern. An auxiliary linear operator is chosen to construct such kind of a continuous mapping and an auxiliary parameter is used to ensure the convergence of series solution. We present the solutions of two-group neutron diffusion equation through HAM in this work. We also compare the results with that obtained by other well-known solution analytical and numeric methods.

Using poison center exposure calls to predict methadone poisoning deaths.

Directory of Open Access Journals (Sweden)

Nabarun Dasgupta

Full Text Available PURPOSE: There are more drug overdose deaths in the Untied States than motor vehicle fatalities. Yet the US vital statistics reporting system is of limited value because the data are delayed by four years. Poison centers report data within an hour of the event, but previous studies suggested a small proportion of poisoning deaths are reported to poison centers (PC. In an era of improved electronic surveillance capabilities, exposure calls to PCs may be an alternate indicator of trends in overdose mortality. METHODS: We used PC call counts for methadone that were reported to the Researched Abuse, Diversion and Addiction-Related Surveillance (RADARS® System in 2006 and 2007. US death certificate data were used to identify deaths due to methadone. Linear regression was used to quantify the relationship of deaths and poison center calls. RESULTS: Compared to decedents, poison center callers tended to be younger, more often female, at home and less likely to require medical attention. A strong association was found with PC calls and methadone mortality (b=0.88, se=0.42, t=9.5, df=1, p<0.0001, R(2 =0.77. These findings were robust to large changes in a sensitivity analysis assessing the impact of underreporting of methadone overdose deaths. CONCLUSIONS: Our results suggest that calls to poison centers for methadone are correlated with poisoning mortality as identified on death certificates. Calls received by poison centers may be used for timely surveillance of mortality due to methadone. In the midst of the prescription opioid overdose epidemic, electronic surveillance tools that report in real-time are powerful public health tools.

Reevaluation of the case, de Hoffman, and Placzek one-group neutron transport benchmark solution in plane geometry

International Nuclear Information System (INIS)

Ganapol, B.D.

1986-01-01

In a course on neutron transport theory and also in the analytical neutron transport theory literature, the pioneering work of Case et al. (CdHP) is often referenced. This work was truly a monumental effort in that it treated the fundamental mathematical properties of the one-group neutron Boltzmann equation in detail as well as the numerical evaluation of most of the resulting solutions. Many mathematically and numerically oriented dissertations were based on this classic monograph. In light of the considerable advances made both in numerical methods and computer technology since 1953, when the historic CdHP monograph first appeared, it seems appropriate to reevaluate the numerical benchmark solutions found therein with present-day computational technology. In most transport theory courses, the subject of proper benchmarking of numerical algorithms and transport codes is seldom addressed at any great length. This may be the reason that the benchmarking procedure is so rarely practiced in the nuclear community and when practiced is improperly applied. In this presentation, the development of a new benchmark for the one-group neutron flux in an infinite medium will be detailed with emphasis placed on the educational aspects of the benchmarking activity

Poisoning in Israel: annual report of the Israel Poison Information Center, 2012.

Science.gov (United States)

Bentur, Yedidia; Lurie, Yael; Cahana, Alfred; Kovler, Nona; Bloom-Krasik, Anna; Gurevych, Bella; Klein-Schwartz, Wendy

2014-11-01

The Israel National Poison Information Center (IPIC), Rambam Health Care Campus, provides 24 hour telephone consultations in clinical toxicology as well as drug and teratogen information. It participates in research, teaching and regulatory activities, and also provides laboratory services. To report data on the epidemiology of poisonings and poison exposures in Israel. We made computerized queries and descriptive analyses of the medical records database of the IPIC during 2012. A total of 31,519 poison exposure cases were recorded, a 157.6% increase compared with 1995. Children snake venom. Four fatalities were recorded; all were intentional exposures in adults (corrosive, medications, energy drink). Poison exposures and poisonings have increased significantly and have contributed substantially to morbidity and mortality in Israel. The IPIC database is a valuable national resource for the collection and monitoring of poisoning exposure cases. It can be used as a real-time surveillance system for the benefit of public health. It is recommended that reporting to the IPIC become mandatory and its activities be adequately supported by national resources.

The mechanism of solute-enriched clusters formation in neutron-irradiated pressure vessel steels: The case of Fe-Cu model alloys

Energy Technology Data Exchange (ETDEWEB)

Subbotin, A.V., E-mail: Alexey.V.Subbotin@gmail.com [Scientific and Production Complex Atomtechnoprom, Moscow 119180 (Russian Federation); Panyukov, S.V., E-mail: panyukov@lpi.ru [PN Lebedev Physics Institute, Russian Academy of Sciences, Moscow 117924 (Russian Federation)

2016-08-15

Mechanism of solute-enriched clusters formation in neutron-irradiated pressure vessel steels is proposed and developed in case of Fe-Cu model alloys. The suggested solute-drag mechanism is analogous to the well-known zone-refining process. We show that the obtained results are in good agreement with available experimental data on the parameters of clusters enriched with the alloying elements. Our model explains why the formation of solute-enriched clusters does not happen in austenitic stainless steels with fcc lattice structure. It also allows to quantify the method of evaluation of neutron irradiation dose for the process of RPV steels hardening.

Neutronic design of an ADS

International Nuclear Information System (INIS)

Cintas, A; Lopasso, E.M; Marquez Damian, J.I

2009-01-01

We present a LEU-ADS design based on an existing Argentine experimental facility, the RA-8 pool type zero power reactor. The versatility of this reactor allows measurement of different core configurations using different fuel enrichment, burnable poison rods, water perturbations and different control rods types in critical or subcritical configurations with an external source. To assess the feasibility of the LEU-ADS, multiplication factors, kinetic parameters, spectra, and time flux evolution were computed. Two external sources were considered: an isotopic 252 C f source, and a D-D pulsed neutron source. Parameters for different core configurations were calculated, and the feasibility of using continuous and pulsed neutron sources was verified. [es

COSTANZA-AX, 1-D Neutronics and Thermodynamics of Liquid Cooled Reactor in Axial Geometry. COSTANZA-CYL, 1-D Neutronics and Thermodynamics of Liquid Cooled Reactor in Cylindrical Geometry

International Nuclear Information System (INIS)

Agazzi, A.; Forti, G.; Vincenti, E.

1984-01-01

1 - Nature of physical problem solved: Purpose of the programmes is to study reactor dynamics, considering the variation of the spatial flux distribution. The two programmes COSTANZA-CYL and COSTANZA-AX, solve the kinetics diffusion equations in two groups and one dimension (plane geometry for COSTANZA-AX, radial geometry for COSTANZA-CYL). The neutronic calculation is coupled with the calculation of the heat transmission from the fuel to the cladding and to the coolant, and with the thermo-hydraulics of channels with forced circulation of liquid coolant. The geometry of fuel element and channel may be cylindrical or slab. Up to ten groups of delayed neutrons are allowed. Temperature feedback of fuel (Doppler) and coolant are considered independently and affect the nuclear constants. Control rod movement or diffused poison concentrations are simulated by externally imposed variations of the thermal absorption cross section in the different regions of the reactors. Inlet temperatures and mass flow in the coolant channels may be varied according to any externally given time table. 2 - Method of solution: The kinetic diffusion equations in two groups are solved by finite-difference method. 3 - Restrictions on the complexity of the problem: 10 concentric regions; 10 coolant channels; 10 groups of delayed neutrons

Merthiolate poisoning

Science.gov (United States)

Merthiolate poisoning is difficult to treat. How well a person does depends on the amount of poison swallowed and how quickly treatment was received. The faster a person gets medical help, the better the chance for recovery. Kidney dialysis ( ...

Neutron spin echo spectroscopy. Its application to the study of the dynamics of polymers in solution; La spectrometrie par echos de spins de neutrons. Application a l'etude de la dynamique des polymeres en solution

Energy Technology Data Exchange (ETDEWEB)

Papoular, Robert

1992-06-15

This work focuses on Neutron Spin Echo (NSE) spectroscopy and on the NSE spectrometer MESS, which we have built at the L.L.B. (CE Saclay). After analyzing in detail the classical and quantum principles of this type of instrument, and illustrated them with optical analogies, we expound a simple formalism for the interpretation of polarized neutron experiments of the most general type. In a second part, we describe the MESS spectrometer extensively; its characteristics and performances as well as the first results obtained with this instrument. In particular, we include two papers showing how the neutron depolarization, spin rotation and echoes can be used to investigate high-Tc superconductors. The last part deals with the dynamics of Polymer-Polymer-Solvent ternary solutions and demonstrates how the Neutron Spin Echo technique becomes a privileged tool for such physico-chemical studies thanks to the joint use of NSE and contrast variation methods, coupled with the adequate ranges of time and scattering vectors accessible. Finally, we describe the specific case of partially deuterated polydimethyl-siloxane (PDMS) in semi-dilute solution in Toluene. We have experimentally and separately evidenced the cooperative and inter-diffusive diffusion modes predicted by the theory of Akcasu, Benoit, Benmouna et al. These results, obtained at the L.L.B. (CE Saclay) are the subject matter of the last paper included in this work. (author) [French] Ce memoire est centre sur la spectroscopie par echos de spins de neutrons, et plus particulierement, sur le spectrometre a echos de spins MESS que nous avons construit au L.L.B (CE/Saclay). Apres avoir detaille les principes classique et quantique de ce type d'instrument et les avoir illustres par des analogies optiques, nous detaillons un formalisme simple permettant d'interpreter les experiences utilisant les neutrons polarises dans le cas le plus general. Une seconde partie decrit de maniere approfondie le spectrometre MESS de Saclay

Diagnosis of acute poisoning | Tygerberg Poison Information Centre ...

African Journals Online (AJOL)

Continuing Medical Education. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 21, No 8 (2003) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Diagnosis of acute poisoning. - Tygerberg Poison ...

Calcium ions in aqueous solutions: Accurate force field description aided by ab initio molecular dynamics and neutron scattering

Science.gov (United States)

Martinek, Tomas; Duboué-Dijon, Elise; Timr, Štěpán; Mason, Philip E.; Baxová, Katarina; Fischer, Henry E.; Schmidt, Burkhard; Pluhařová, Eva; Jungwirth, Pavel

2018-06-01

We present a combination of force field and ab initio molecular dynamics simulations together with neutron scattering experiments with isotopic substitution that aim at characterizing ion hydration and pairing in aqueous calcium chloride and formate/acetate solutions. Benchmarking against neutron scattering data on concentrated solutions together with ion pairing free energy profiles from ab initio molecular dynamics allows us to develop an accurate calcium force field which accounts in a mean-field way for electronic polarization effects via charge rescaling. This refined calcium parameterization is directly usable for standard molecular dynamics simulations of processes involving this key biological signaling ion.

Beryllium poisonings

International Nuclear Information System (INIS)

Alibert, S.

1959-03-01

This note reports a bibliographical study of beryllium toxicity. Thus, this bibliographical review addresses and outlines aspects and issues like aetiology, cases of acute poisoning (cutaneous manifestations, pulmonary manifestations), chronic poisoning (cutaneous, pulmonary and bone manifestations), excretion and localisation, and prognosis

Spherical harmonics solutions of multi-dimensional neutron transport equation by finite Fourier transformation

International Nuclear Information System (INIS)

Kobayashi, Keisuke

1977-01-01

A method of solution of a monoenergetic neutron transport equation in P sub(L) approximation is presented for x-y and x-y-z geometries using the finite Fourier transformation. A reactor system is assumed to consist of multiregions in each of which the nuclear cross sections are spatially constant. Since the unknown functions of this method are the spherical harmonics components of the neutron angular flux at the material boundaries alone, the three- and two-dimensional equations are reduced to two- and one-dimensional equations, respectively. The present approach therefore gives fewer unknowns than in the usual series expansion method or in the finite difference method. Some numerical examples are shown for the criticality problem. (auth.)

Evaluation of poison information services provided by a new poison information center.

Science.gov (United States)

Churi, Shobha; Abraham, Lovin; Ramesh, M; Narahari, M G

2013-01-01

The aim of this study is to assess the nature and quality of services provided by poison information center established at a tertiary-care teaching hospital, Mysore. This was a prospective observational study. The poison information center was officially established in September 2010 and began its functioning thereafter. The center is equipped with required resources and facility (e.g., text books, Poisindex, Drugdex, toll free telephone service, internet and online services) to provide poison information services. The poison information services provided by the center were recorded in documentation forms. The documentation form consists of numerous sections to collect information on: (a) Type of population (children, adult, elderly or pregnant) (b) poisoning agents (c) route of exposure (d) type of poisoning (intentional, accidental or environmental) (e) demographic details of patient (age, gender and bodyweight) (f) enquirer details (background, place of call and mode of request) (g) category and purpose of query and (h) details of provided service (information provided, mode of provision, time taken to provide information and references consulted). The nature and quality of poison information services provided was assessed using a quality assessment checklist developed in accordance with DSE/World Health Organization guidelines. Chi-Square test (χ(2)). A total of 419 queries were received by the center. A majority (n = 333; 79.5%) of the queries were asked by the doctors to provide optimal care (n = 400; 95.5%). Most of the queries were received during ward rounds (n = 201; 48.0%), followed by direct access (n = 147; 35.1%). The poison information services were predominantly provided through verbal communication (n = 352; 84.0%). Upon receipt of queries, the required service was provided immediately (n = 103; 24.6%) or within 10-20 min (n = 296; 70.6%). The queries were mainly related to intentional poisoning (n = 258; 64.5%), followed by accidental poisoning

Sources of neutronics data involving thorium of 233U and light water moderation

International Nuclear Information System (INIS)

Davenport, L.C.

1978-11-01

A literature search has been conducted to locate sources of neutronics data for light water moderated systems which contain thorium and/or uranium-233. It is concluded that insufficient data is currently available to validate neutronics design methods for licensing the 233 UO 2 -ThO 2 fuel cycle in light water reactors. A summary of the neutronics data sources found is reported in this document. These sources include critical and exponential experiments with lattices of fuel rods containing 233 U + Th or 235 U + Th. A few experiments using homogeneous aqueous solutions of 233 UO 2 (NO 3 ) 2 or 233 UO 2 F 2 are also included. The only critical lattice data using both 233 U and Th came from the LWBR program. All these experiments were zoned radially and in most cases axially also. Geometrically clean lattice critical data were measured for the CETR and TUPE programs. Both series used 235 UO 2 -ThO 2 pellets. A series of 21 exponential experiments using 3% 233 UO 2 - 97% ThO 2 fuel vibratory compacted to 92% of theoretical density in Zircaloy-2 tubing was performed at BNL using both unpoisoned and boric acid poisoned H 2 O moderator. For completeness, homogeneous systems are listed in which basic neutronics data have been measured. However, it is expected that most data concerning homogeneous systems will be applied to criticality safety problems rather than neutronics methods validation

Advances in the solution of three-dimensional nodal neutron transport equation

International Nuclear Information System (INIS)

Pazos, Ruben Panta; Hauser, Eliete Biasotto; Vilhena, Marco Tullio de

2003-01-01

In this paper we study the three-dimensional nodal discrete-ordinates approximations of neutron transport equation in a convex domain with piecewise smooth boundaries. We use the combined collocation method of the angular variables and nodal approach for the spatial variables. By nodal approach we mean the iterated transverse integration of the S N equations. This procedure leads to the set of one-dimensional averages angular fluxes in each spatial variable. The resulting system of equations is solved with the LTS N method, first applying the Laplace transform to the set of the nodal S N equations and then obtaining the solution by symbolic computation. We include the LTS N method by diagonalization to solve the nodal neutron transport equation and then we outline the convergence of these nodal-LTS N approximations with the help of a norm associated to the quadrature formula used to approximate the integral term of the neutron transport equation. We give numerical results obtained with an algebraic computer system (for N up to 8) and with a code for higher values of N. We compare our results for the geometry of a box with a source in a vertex and a leakage zone in the opposite with others techniques used in this problem. (author)

Small-angle neutron scattering study of D2O-alcohol solutions

International Nuclear Information System (INIS)

D'Arrigo, G.

1990-01-01

Small-angle neutron scattering (SANS) measurements have been carried out on heavy water solutions of ethanol, isopropyl alcohol, n-propyl alcohol, t-butyl alcohol and butoxyethanol between 5 and 37 0 C at the concentrations where ultrasonic attenuation exhibits peak values. The wavevector dependence and the absolute intensity of the scattered intensities were analysed according to a microscopic model of the solutions in terms of aggregated complexes. The results indicate that at 25 0 C there exist either alcohol 'micelle-like' structures or alcohol-heavy water complexes which increase on going from the lower to higher alcohol solutions. As temperature increases from 25 to 37 0 C a higher aggregation is observed in butyl alcohol and butoxyethanol solutions. This behaviour is attributed to the demixing tendency of these systems at high temperatures. On going from 25 to 5 0 C the aggregation increases again. This trend is associated with the anomalous behaviour of the specific heat and ultrasonic attenuation of these systems. The occurrence of a low-temperature phase transition suggested by these anomalies is supported by our results. (author)

Comparative study of structural properties of trehalose water solutions by neutron diffraction, synchrotron radiation and simulation

Energy Technology Data Exchange (ETDEWEB)

Cesaro, A.; Magazu, V.; Migliardo, F.; Sussich, F.; Vadala, M

2004-07-15

Neutron diffraction measurements combined with H/D substitution have been performed on trehalose aqueous solutions as a function of temperature and concentration by using the SANDALS diffractometer at ISIS Facility (UK). The findings point out a high capability of trehalose to strongly affect the tetrahedral hydrogen bond network of water. The neutron diffraction results are also compared with simulation and experimental data obtained by synchrotron radiation on the phospholipid bilayer membranes (DPPC)/trehalose/H{sub 2}O ternary system.

Concentration dependence of solute atoms on vacancy cluster formation in neutron irradiated Ni alloy

International Nuclear Information System (INIS)

Sato, K.; Itoh, D.; Yoshiie, T.; Xu, Q.

2007-01-01

Full text of publication follows: One dimensional (1-D) motion of interstitial clusters is important for the microstructural evolution in metals. The movement of interstitial clusters was often observed in neutron irradiated metals by transmission electron microscopy (TEM). Alloying elements are expected to affect the motion of interstitial clusters. Yoshiie et al. have studied the effect of alloying elements in Ni. For example, in neutron irradiated pure Ni, well-developed dislocation networks and voids were observed at 573 K at a dose of 0.026 dpa by TEM. After the addition of 2at.%Si (-5.81% volume size factor to Ni) and Sn (74.08% volume size factor), no voids were detected by TEM observation and positron lifetime measurement. Alloying elements of Si and Sn were expected to prevent the 1-D motion of the interstitial clusters. In this study, the concentration dependence of alloying elements on the 1-D motion of the interstitial clusters was investigated by positron annihilation lifetime measurements, and the microstructural evolution was discussed. Specimens irradiated were 99.99 pure Ni (Johnson Matthey) and Ni based binary alloys, which contain Si, Cu, Ge and Sn as solute atoms. The concentration of solute atoms was 0.05at.%o, 0.3at.% and 2at.%. Neutron irradiation was performed with the Kyoto University Reactor (KUR) and Japan materials testing reactor (JMTR) at Japan Atomic Energy Agency. Neutron dose was 6x10 -5 -1x10 -2 dpa at KUR, and 8x10 -3 -0.3 dpa at JMTR. Irradiation temperature was 573 K at KUR and 563 K at JMTR. After the neutron irradiation, positron annihilation lifetime measurements were performed at room temperature. Microvoids were detected in pure Ni, Ni-0.05%Si, Ni-0.05%Sn, Ni-Cu and Ni-Ge alloys. In Ni-Si and Ni-Sn alloys, the size of microvoids decreased as the concentration of solute atoms increased. This is because the frequency of 1-D motion of the interstitial clusters depends on the alloy concentration. High concentration of alloying

Concentration dependence of solute atoms on vacancy cluster formation in neutron irradiated Ni alloy

Energy Technology Data Exchange (ETDEWEB)

Sato, K.; Itoh, D.; Yoshiie, T.; Xu, Q. [Kyoto Univ., Research Reactor Institute, Osaka (Japan)

2007-07-01

Full text of publication follows: One dimensional (1-D) motion of interstitial clusters is important for the microstructural evolution in metals. The movement of interstitial clusters was often observed in neutron irradiated metals by transmission electron microscopy (TEM). Alloying elements are expected to affect the motion of interstitial clusters. Yoshiie et al. have studied the effect of alloying elements in Ni. For example, in neutron irradiated pure Ni, well-developed dislocation networks and voids were observed at 573 K at a dose of 0.026 dpa by TEM. After the addition of 2at.%Si (-5.81% volume size factor to Ni) and Sn (74.08% volume size factor), no voids were detected by TEM observation and positron lifetime measurement. Alloying elements of Si and Sn were expected to prevent the 1-D motion of the interstitial clusters. In this study, the concentration dependence of alloying elements on the 1-D motion of the interstitial clusters was investigated by positron annihilation lifetime measurements, and the microstructural evolution was discussed. Specimens irradiated were 99.99 pure Ni (Johnson Matthey) and Ni based binary alloys, which contain Si, Cu, Ge and Sn as solute atoms. The concentration of solute atoms was 0.05at.%o, 0.3at.% and 2at.%. Neutron irradiation was performed with the Kyoto University Reactor (KUR) and Japan materials testing reactor (JMTR) at Japan Atomic Energy Agency. Neutron dose was 6x10{sup -5}-1x10{sup -2} dpa at KUR, and 8x10{sup -3} -0.3 dpa at JMTR. Irradiation temperature was 573 K at KUR and 563 K at JMTR. After the neutron irradiation, positron annihilation lifetime measurements were performed at room temperature. Microvoids were detected in pure Ni, Ni-0.05%Si, Ni-0.05%Sn, Ni-Cu and Ni-Ge alloys. In Ni-Si and Ni-Sn alloys, the size of microvoids decreased as the concentration of solute atoms increased. This is because the frequency of 1-D motion of the interstitial clusters depends on the alloy concentration. High

Neutron collar calibration for assay of LWR [light-water reactor] fuel assemblies

International Nuclear Information System (INIS)

Menlove, H.O.; Pieper, J.E.

1987-03-01

The neutron-coincidence collar is used for the verification of the uranium content in light-water reactor fuel assemblies. An AmLi neutron source is used to give an active interrogation of the fuel assembly to measure the 235 U content, and the 238 U content is verified from a passive neutron-coincidence measurement. This report gives the collar calibration data of pressurized-water reactor and boiling-water reactor fuel assemblies. Calibration curves and correction factors are presented for neutron absorbers (burnable poisons) and different fuel assembly sizes. The data were collected at Exxon Nuclear, Franco-Belge de Fabrication de Combustibles, ASEA-Atom, and other nuclear fuel fabrication facilities

Neutron spin echo spectroscopy. Its application to the study of the dynamics of polymers in solution

International Nuclear Information System (INIS)

Papoular, Robert

1992-06-01

This work focuses on Neutron Spin Echo (NSE) spectroscopy and on the NSE spectrometer MESS, which we have built at the L.L.B. (CE Saclay). After analyzing in detail the classical and quantum principles of this type of instrument, and illustrated them with optical analogies, we expound a simple formalism for the interpretation of polarized neutron experiments of the most general type. In a second part, we describe the MESS spectrometer extensively; its characteristics and performances as well as the first results obtained with this instrument. In particular, we include two papers showing how the neutron depolarization, spin rotation and echoes can be used to investigate high-Tc superconductors. The last part deals with the dynamics of Polymer-Polymer-Solvent ternary solutions and demonstrates how the Neutron Spin Echo technique becomes a privileged tool for such physico-chemical studies thanks to the joint use of NSE and contrast variation methods, coupled with the adequate ranges of time and scattering vectors accessible. Finally, we describe the specific case of partially deuterated polydimethyl-siloxane (PDMS) in semi-dilute solution in Toluene. We have experimentally and separately evidenced the cooperative and inter-diffusive diffusion modes predicted by the theory of Akcasu, Benoit, Benmouna et al. These results, obtained at the L.L.B. (CE Saclay) are the subject matter of the last paper included in this work. (author) [fr

Proceedings of the 182nd basic science seminar (The workshop on neutron structural biology ) 'New frontiers of structural biology advanced by solution scattering'

Energy Technology Data Exchange (ETDEWEB)

Fujiwara, Satoru (ed.) [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2001-03-01

182nd advanced science seminar (the workshop on neutron structural biology) was held in February 9-10, 2000 at Tokai. Thirty-six participants from universities, research institutes, and private companies took part in the workshop, and total of 24 lectures were given. This proceedings collects abstracts, the figures and tables, which the speakers used in their lectures. The proceedings contains two reviews from the point of view of x-ray and neutron scatterings, and six subjects (21 papers) including neutron and x-ray scattering in the era of structure genomics, structural changes detected with solution scattering, a new way in structural biology opened by neutron crystallography and neutron scattering, x-ray sources and detectors, simulation and solution scattering, and neutron sources and detectors. (Kazumata, Y.)

Lead Poisoning (For Parents)

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español Lead Poisoning KidsHealth / For Parents / Lead Poisoning What's in ... Print en español La intoxicación por plomo About Lead Poisoning If you have young kids, it's important ...

Optimization of gadolinium burnable poison loading by the conjugate gradients method

International Nuclear Information System (INIS)

Drumm, C.R.

1984-01-01

Improved use of burnable poison is suggested for pressurized water reactors (PWR's) to insure a sufficiently negative moderator temperature coefficient of reactivity for extended burnup cycles and low leakage refueling patterns. The use of gadolinium as a burnable poison can lead to large axial fluctuations in the power distribution through the cycle. The goal of this work is to determine the optimal axial distribution of gadolinium burnable poison in a PWR to overcome the axial fluctuations, yielding an improved power distribution. The conjugate gradients optimization method is used in this work because of the high degree of nonlinearity of the problem. The neutron diffusion and depletion equations are solved for a one-dimensional one-group core model. The state variables are the flux, the critical soluble boron concentration, and the burnup. The control variables are the number of gadolinium pins per assembly and the beginning-of-cycle gadolinium concentration, which determine the gadolinium cross section. Two separate objectives are considered: 1) to minimize the power peaking factor, which will minimize the capital cost of the plant; and 2) to maximize the cycle length, which will minimize the fuel cost for the plant. It is shown in this work that optimizing the gadolinium distribution can yield an improved power distribution

Reactor neutron converter into antineutrinos on base of lithium compounds and their solutions

International Nuclear Information System (INIS)

Lyutostanskij, Yu.S.; Lyashchuk, V.I.

1990-01-01

A study on the possibility of using various lithium compounds as substances for reactor neutron converter into antineutrinos, was made. It is concluded that heavy water LiOD, LiODxD 2 O, LiD solutions are the most promising ones. They provide for high efficiency with reduction of the required lithium mass (300-350 times maximum) as compared with pure lithium converter

Tropical fish poisoning in temperate climates: food poisoning from ciguatera toxin presenting in Avonmouth.

Science.gov (United States)

Kipping, Ruth; Eastcott, Howard; Sarangi, Joyshri

2006-12-01

Ciguatera toxin causes a range of gastrointestinal, cardiovascular and neurological symptoms that occur within 1-6 h of ingesting fish with the toxin and can last for days, months or years. It is a well-recognized problem in the tropics. Avon Health Protection Team investigated food poisoning on a ship at Avonmouth, which was thought by the crew to be related to a white snapper fish from the Caribbean. The symptoms were initially thought to be scombroid fish poisoning but were consistent with ciguatera fish poisoning. Cases of fish poisoning from fish imported from the Caribbean and Pacific or travellers returning from tropical countries may be ciguatera fish poisoning, but mistakenly diagnosed as scombroid fish poisoning.

Fuelling study of CANDU reactors using neutron absorber poisoned fuel

Energy Technology Data Exchange (ETDEWEB)

Song, J.J.; Chan, P.K.; Bonin, H.W., E-mail: s25815@rmc.ca [Royal Military College of Canada, Kingston, ON (Canada)

2014-07-01

A comparative fuelling study is conducted to determine the potential gain in operating margin for CANDU reactors incurred by implementing a change to the design of the conventional 37-element natural uranium (NU) fuel. The change involves insertion of minute quantities of neutron absorbers, Gd{sub 2}O{sub 3} and Eu{sub 2}O{sub 3}, into the fuel pellets. The Reactor Fuelling Simulation Program (RFSP) is used to conduct core-following simulations, for the regular 37-element NU fuel, which is to be used as control for comparison. Preliminary results are presented for fuelling with the regular 37-element NU fuel, which indicate constraints on fuelling that may be relaxed with addition of neutron absorbers. (author)

Optimization of control poison management by dynamic programming

International Nuclear Information System (INIS)

Ponzoni Filho, P.

1974-01-01

A dynamic programming approach was used to optimize the poison distribution in the core of a nuclear power plant between reloading. This method was applied to a 500 M We PWR subject to two different fuel management policies. The beginning of a stage is marked by a fuel management decision. The state vector of the system is defined by the burnups in the three fuel zones of the core. The change of the state vector is computed in several time steps. A criticality conserving poison management pattern is chosen at the beginning of each step. The burnups at the end of a step are obtained by means of depletion calculations, assuming constant neutron distribution during the step. The violation of burnup and power peaking constraints during the step eliminates the corresponding end states. In the case of identical end states, all except that which produced the largest amount of energy, are eliminated. Among the several end states one is selected for the subsequent stage, when it is subjected to a fuel management decision. This selection is based on an optimally criterion previously chosen, such as: discharged fuel burnup maximization, energy generation cost minimization, etc. (author)

Extracorporeal Treatment for Lithium Poisoning

DEFF Research Database (Denmark)

Decker, Brian S; Goldfarb, David S; Dargan, Paul I

2015-01-01

The Extracorporeal Treatments in Poisoning Workgroup was created to provide evidence-based recommendations on the use of extracorporeal treatments in poisoning. Here, the EXTRIP workgroup presents its recommendations for lithium poisoning. After a systematic literature search, clinical and toxico......The Extracorporeal Treatments in Poisoning Workgroup was created to provide evidence-based recommendations on the use of extracorporeal treatments in poisoning. Here, the EXTRIP workgroup presents its recommendations for lithium poisoning. After a systematic literature search, clinical...... extraction of patient-level data. The workgroup concluded that lithium is dialyzable (Level of evidence=A) and made the following recommendations: Extracorporeal treatment is recommended in severe lithium poisoning (1D). Extracorporeal treatment is recommended if kidney function is impaired and the [Li...... treatment (1D), but continuous RRT is an acceptable alternative (1D). The workgroup supported the use of extracorporeal treatment in severe lithium poisoning. Clinical decisions on when to use extracorporeal treatment should take into account the [Li(+)], kidney function, pattern of lithium toxicity...

Pick your poison: what's new in poison control for the preschooler.

Science.gov (United States)

Glenn, Lauren

2015-01-01

Accidental childhood poisonings are a major public health concern despite many efforts to alleviate this problem. While the rate of pediatric fatalities due to poisonings have decreased over the last two decades, poison control centers around the US have collectively fielded over one million calls with regard to toxic exposures in the preschool age group. According to the American Association of Poison Control Centers nearly half of all human exposures reported last year involved children under six. By focusing poison prevention efforts on the preschooler, we can attempt to decrease morbidity and mortality in the most vulnerable age group affected. Although the subject is still prevalent, current discussion on this topic is limited. Newer literature discusses past initiatives such as child resistant packaging and sticker deterrent programs and addresses their efficacy. This article revisits older mechanisms of prevention as well as the science behind the human motivation to change one's own practice and behavior. Copyright © 2015 Elsevier Inc. All rights reserved.

Dynamical scaling in polymer solutions investigated by the neutron spin echo technique

International Nuclear Information System (INIS)

Richter, D.; Ewen, B.

1979-01-01

Chain dynamics in polymer solutions was investigated by means of the recently developed neutron spin echo spectroscopy. - By this technique, it was possible for the first time to verify unambiguously the scaling predictions of the Zimm model in the case of single chain behaviour and to observe the cross over to many chain behaviour. The segmental diffusion of single chains exhibits deviations from a simple exponential law, indicating the importance of memory effects. (orig.) [de

The KASY synthesis programme for the approximative solution of the 3-dimensional neutron diffusion equation

International Nuclear Information System (INIS)

Buckel, G.; Wouters, R. de; Pilate, S.

1977-01-01

The synthesis code KASY for an approximate solution of the three-dimensional neutron diffusion equation is described; the state of the art as well as envisaged program extensions and the application to tasks from the field of reactor designing are dealt with. (RW) [de

Comparison of poisonings managed at military and Veterans Administration hospitals reported to Texas poison centers.

Science.gov (United States)

Forrester, M B

2017-01-01

There is little information on poisonings managed at military and Veterans Administration (VA) hospitals. This investigation described and compared poisonings reported to Texas poison centers that were managed at military and VA hospitals. Retrospective analysis of poison centre data. Cases were poisonings among patients aged 18 years or more reported to Texas poison centers during 2000-2015 where management occurred at a military or VA hospital. The distribution of exposures for various demographic and clinical factors was determined for military and veterans hospitals and comparisons were made between the two groups. There were 4353 and 1676 poisonings managed at military and VA hospitals, resepctively. Males accounted for 50.5% of the military hospital patients and 84.9% of the VA hospital patients. The mean age for military hospital patients was 31 years and for VA hospital patients was 50 years. The proportion of poisonings managed at military hospitals and VA hospitals, respectively, were intentional (70.0% vs 64.1%), particularly suspected attempted suicide (57.3% vs 47.7%), and unintentional (25.0% vs 30.5%). More than one substance was reported in 37.7% of military and 33.2% of VA hospital poisonings. The most commonly reported substance categories for poisonings managed at military and VA hospitals, respectively, were analgesics (28.4% vs 19.7%), sedatives/hypnotics/antipsychotics (24.7% vs 23.4%), antidepressants (18.7% vs 19.7%) and alcohol (11.3% vs 10.6%). A number of differences were observed between poisonings managed at military and VA hospitals. These differing patterns of poisonings may need to be taken into account in the education, prevention and treatment of poisonings at these hospitals and among the populations they serve. Copyright © 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Dissolution of Simulated and Radioactive Savannah River Site High-Level Waste Sludges with Oxalic Acid & Citric Acid Solutions

International Nuclear Information System (INIS)

STALLINGS, MARY

2004-01-01

This report presents findings from tests investigating the dissolution of simulated and radioactive Savannah River Site sludges with 4 per cent oxalic acid and mixtures of oxalic and citric acid previously recommended by a Russian team from the Khlopin Radium Institute and the Mining and Chemical Combine (MCC). Testing also included characterization of the simulated and radioactive waste sludges. Testing results showed the following: Dissolution of simulated HM and PUREX sludges with oxalic and citric acid mixtures at SRTC confirmed general trends reported previously by Russian testing. Unlike the previous Russian testing six sequential contacts of a mixture of oxalic acid citric acids at a 2:1 ratio (v/w) of acid to sludge did not produce complete dissolution of simulated HM and PUREX sludges. We observed that increased sludge dissolution occurred at a higher acid to sludge ratio, 50:1 (v/w), compared to the recommended ratio of 2:1 (v/w). We observed much lower dissolution of aluminum in a simulated HM sludge by sodium hydroxide leaching. We attribute the low aluminum dissolution in caustic to the high fraction of boehmite present in the simulated sludge. Dissolution of HLW sludges with 4 per cent oxalic acid and oxalic/citric acid followed general trends observed with simulated sludges. The limited testing suggests that a mixture of oxalic and citric acids is more efficient for dissolving HM and PUREX sludges and provides a more homogeneous dissolution of HM sludge than oxalic acid alone. Dissolution of HLW sludges in oxalic and oxalic/citric acid mixtures produced residual sludge solids that measured at higher neutron poison to equivalent 235U weight ratios than that in the untreated sludge solids. This finding suggests that residual solids do not present an increased nuclear criticality safety risk. Generally the neutron poison to equivalent 235U weight ratios of the acid solutions containing dissolved sludge components are lower than those in the untreated

Contribution to analytical solution of neutron slowing down problem in homogeneous and heterogeneous media; Prilog analitickom resavanju problema usporavanja neutrona u homogenim i heterogenim sredinama

Energy Technology Data Exchange (ETDEWEB)

Stefanovic, D B [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Yugoslavia)

1970-07-01

The objective of this work is to describe the new analytical solution of the neutron slowing down equation for infinite monoatomic media with arbitrary energy dependence of cross section. The solution is obtained by introducing Green slowing down functions instead of starting from slowing down equations directly. The previously used methods for calculation of fission neutron spectra in the reactor cell were numerical. The proposed analytical method was used for calculating the space-energy distribution of fast neutrons and number of neutron reactions in a thermal reactor cell. The role of analytical method in solving the neutron slowing down in reactor physics is to enable understating of the slowing down process and neutron transport. The obtained results could be used as standards for testing the accuracy od approximative and practical methods.

Poison control services in China

International Nuclear Information System (INIS)

Wu Yiqun; Sun Chengye

2004-01-01

The following aspects are discussed: the public health problems of acute poisoning in China in recent years; the characteristics of acute poisoning; the negative effects of poison cases on the society and economy. The four stages of development of a poison control system in China are: (1) clinical hospital as the only facility used for detoxification; (2) institutes and hospitals of occupational medicine got involved in the program; (3) the traditional model of poison control changed to the modern National Poison Control Center (NPCC), and its network got established and it began to play a key role; (4) establishment of a multi-disciplinary network for dealing with emergencies in which chemical poison control is an important component. Introduction of the operations of the NPCC: the functions of the center are a 24 h hotline service, clinical consultants service, poison identification and diagnosis, laboratory analysis, education for public, training for physicians, coordination of anti-dotes, and the development of a network of poison control centers for dealing with chemical emergencies. The work practice and achievement of NPCC and its network in the field of poison control during the last 3 years is discussed. Lessons from SARS infection: to extend the network, to strengthen multi-disciplinary cooperation, enhance communication between centers, to pay attention to capacity building, to improve reporting systems, and to share resources

Solution and Study of the Two-Dimensional Nodal Neutron Transport Equation

International Nuclear Information System (INIS)

Panta Pazos, Ruben; Biasotto Hauser, Eliete; Tullio de Vilhena, Marco

2002-01-01

In the last decade Vilhena and coworkers reported an analytical solution to the two-dimensional nodal discrete-ordinates approximations of the neutron transport equation in a convex domain. The key feature of these works was the application of the combined collocation method of the angular variable and nodal approach in the spatial variables. By nodal approach we mean the transverse integration of the SN equations. This procedure leads to a set of one-dimensional S N equations for the average angular fluxes in the variables x and y. These equations were solved by the old version of the LTS N method, which consists in the application of the Laplace transform to the set of nodal S N equations and solution of the resulting linear system by symbolic computation. It is important to recall that this procedure allow us to increase N the order of S N up to 16. To overcome this drawback we step forward performing a spectral painstaking analysis of the nodal S N equations for N up to 16 and we begin the convergence of the S N nodal equations defining an error for the angular flux and estimating the error in terms of the truncation error of the quadrature approximations of the integral term. Furthermore, we compare numerical results of this approach with those of other techniques used to solve the two-dimensional discrete approximations of the neutron transport equation. (authors)

[Plant poisoning cases in Turkey].

Science.gov (United States)

Oztekin-Mat, A

1994-01-01

In Turkey, the majority of the population live in rural areas where they use wild plants as food and medicine. The confusion of an edible plant with a poisonous one give rise to serious poisoning which may even result in death. The incidence of plant poisoning in Turkey is about 6% and especially high among children between ages of 2 and 11 living in rural areas. The number of species that cause poisoning is around twenty and Hyoscyamus niger (Solanaceae), Colchicum species (Liliaceae), Conium maculatum (Umbelliferae) and Prunus species (Rosaceae) are the most important. Mushroom poisoning is more frequent in spring and fall. The main reasons are their widespread usage as food and the inexperience of the gatherers in distinguishing the edibles from the poisonous. Amanita phalloides, A. verna, A. muscaria, A. pantherina are responsible for severe cases of poisoning.

Solution and study of nodal neutron transport equation applying the LTSN-DiagExp method

International Nuclear Information System (INIS)

Hauser, Eliete Biasotto; Pazos, Ruben Panta; Vilhena, Marco Tullio de; Barros, Ricardo Carvalho de

2003-01-01

In this paper we report advances about the three-dimensional nodal discrete-ordinates approximations of neutron transport equation for Cartesian geometry. We use the combined collocation method of the angular variables and nodal approach for the spatial variables. By nodal approach we mean the iterated transverse integration of the S N equations. This procedure leads to the set of one-dimensional averages angular fluxes in each spatial variable. The resulting system of equations is solved with the LTS N method, first applying the Laplace transform to the set of the nodal S N equations and then obtained the solution by symbolic computation. We include the LTS N method by diagonalization to solve the nodal neutron transport equation and then we outline the convergence of these nodal-LTS N approximations with the help of a norm associated to the quadrature formula used to approximate the integral term of the neutron transport equation. (author)

Solution of the neutron transport problem with anisotropic scattering in cylindrical geometry by the decomposition method

International Nuclear Information System (INIS)

Goncalves, G.A.; Bogado Leite, S.Q.; Vilhena, M.T. de

2009-01-01

An analytical solution has been obtained for the one-speed stationary neutron transport problem, in an infinitely long cylinder with anisotropic scattering by the decomposition method. Series expansions of the angular flux distribution are proposed in terms of suitably constructed functions, recursively obtainable from the isotropic solution, to take into account anisotropy. As for the isotropic problem, an accurate closed-form solution was chosen for the problem with internal source and constant incident radiation, obtained from an integral transformation technique and the F N method

An approach to estimate the reactivity worth of R-5 poison tube system and experimental verification in ZERLINA reactor

International Nuclear Information System (INIS)

Khosla, S.K.; Paul, O.P.K.; Sengupta, S.N.

1976-01-01

It is proposed to employ a liquid poison injection system as an emergency shut down device for R-5 reactor. The liquid poison consists of gadolinium nitrate solution, which is injected into twenty poison tubes made of zircaloy that are located in between the regular lattice positions in R-5 reactor. The calculational model adopted to estimate the reactivity worth of the poison tubes so as to hold the reactor subcritical by 50 mk at full tank, is described. Similar reactivity estimates have also been carried out for R-5 poison tubes installed in Zerlina reactor in order to assess the adequacy of the calculational mode. The results of the calculations are compared with experimental values for single poison tubes. (author)

Poisoning of liquid membrane carriers in extraction of metal ions

International Nuclear Information System (INIS)

Wang, Yuchun; Wang, Dexian

1992-01-01

As means of effective separation and preconcentration, emulsion liquid membranes (ELMs) have found application in many fields including biochemical separation, wastewater treatment, hydrometallurgy, and preconcentration in analytical chemistry. In the extraction of desired metal (scandium, mixed rare earths) ions using chelating extractants (TTA, HDEHP) as liquid membrane carriers, the carriers will become poisoned owing to the presence of even minute quantity of certain high ionic potential ions in the feed solution. The reason for the poisoning of carriers is that those ions have so much greater affinity than the desired ions for the membrane carrier that the ion-carrier coordination compound cannot be stripped at the interior interface of the membrane and gradually no more free carrier transports any metal ions across the membrane. The calculated results are in agreement with the experiments, and methods to avoid the poisoning are given in the paper

Mercuric chloride poisoning

Science.gov (United States)

... page: //medlineplus.gov/ency/article/002474.htm Mercuric chloride poisoning To use the sharing features on this page, please enable JavaScript. Mercuric chloride is a very poisonous form of mercury. It ...

Hair straightener poisoning

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/002706.htm Hair straightener poisoning To use the sharing features on this page, please enable JavaScript. Hair straightener poisoning occurs when someone swallows products that ...

Hair spray poisoning

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/002705.htm Hair spray poisoning To use the sharing features on this page, please enable JavaScript. Hair spray poisoning occurs when someone breathes in (inhales) ...

Determinants of U.S. poison center utilization.

Science.gov (United States)

Litovitz, Toby; Benson, Blaine E; Youniss, Jessica; Metz, Edward

2010-06-01

High poison center utilization has been associated with decreased emergency department usage and hospitalization rates. However, utilization requires awareness of the poison center. Penetrance, defined as the number of human poison exposures reported to a poison center per 1,000 population, has been used as a marker of poison center awareness. To identify factors that influence poison center penetrance to optimize the life- and cost-saving benefits of poison control centers. Human poison exposures that were reported to the National Poison Data System in 2001 were analyzed to identify and rank factors affecting poison center penetrance. Overall penetrance correlated with pediatric penetrance (R(2) = 0.75, p poison center that were already in or en route to a healthcare facility at the time of the call to the poison center (R(2) = 0.41, p poison center service populations were associated with lower penetrance (R(2) = 0.23, p poison center (multiple regression). Positive predictors included the percentage of the population younger than 5 years, the percentage of the adult population with a bachelor's degree, poison center certification, poison center educator FTEs (full time equivalents), Asian population percentage, and population density. The inverse correlation between pediatric penetrance and healthcare facility utilization supports prior observations of excessive healthcare utilization when a poison center is not called. Since race, language and distance are barriers to poison center utilization, and since healthcare utilization increases when poison center penetrance declines, low penetrance suggests a lack of awareness of the poison center rather than a low incidence of poisonings. Strategies to raise penetrance should be informed by an understanding of the barriers to utilization - language, Black/African American race, distance from the poison center, poverty, and lower education levels.

The solution of the neutron point kinetics equation with stochastic extension: an analysis of two moments

Energy Technology Data Exchange (ETDEWEB)

Silva, Milena Wollmann da; Vilhena, Marco Tullio M.B.; Bodmann, Bardo Ernst J.; Vasques, Richard, E-mail: milena.wollmann@ufrgs.br, E-mail: vilhena@mat.ufrgs.br, E-mail: bardobodmann@ufrgs.br, E-mail: richard.vasques@fulbrightmail.org [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica

2015-07-01

The neutron point kinetics equation, which models the time-dependent behavior of nuclear reactors, is often used to understand the dynamics of nuclear reactor operations. It consists of a system of coupled differential equations that models the interaction between (i) the neutron population; and (II) the concentration of the delayed neutron precursors, which are radioactive isotopes formed in the fission process that decay through neutron emission. These equations are deterministic in nature, and therefore can provide only average values of the modeled populations. However, the actual dynamical process is stochastic: the neutron density and the delayed neutron precursor concentrations vary randomly with time. To address this stochastic behavior, Hayes and Allen have generalized the standard deterministic point kinetics equation. They derived a system of stochastic differential equations that can accurately model the random behavior of the neutron density and the precursor concentrations in a point reactor. Due to the stiffness of these equations, this system was numerically implemented using a stochastic piecewise constant approximation method (Stochastic PCA). Here, we present a study of the influence of stochastic fluctuations on the results of the neutron point kinetics equation. We reproduce the stochastic formulation introduced by Hayes and Allen and compute Monte Carlo numerical results for examples with constant and time-dependent reactivity, comparing these results with stochastic and deterministic methods found in the literature. Moreover, we introduce a modified version of the stochastic method to obtain a non-stiff solution, analogue to a previously derived deterministic approach. (author)

The solution of the neutron point kinetics equation with stochastic extension: an analysis of two moments

International Nuclear Information System (INIS)

Silva, Milena Wollmann da; Vilhena, Marco Tullio M.B.; Bodmann, Bardo Ernst J.; Vasques, Richard

2015-01-01

The neutron point kinetics equation, which models the time-dependent behavior of nuclear reactors, is often used to understand the dynamics of nuclear reactor operations. It consists of a system of coupled differential equations that models the interaction between (i) the neutron population; and (II) the concentration of the delayed neutron precursors, which are radioactive isotopes formed in the fission process that decay through neutron emission. These equations are deterministic in nature, and therefore can provide only average values of the modeled populations. However, the actual dynamical process is stochastic: the neutron density and the delayed neutron precursor concentrations vary randomly with time. To address this stochastic behavior, Hayes and Allen have generalized the standard deterministic point kinetics equation. They derived a system of stochastic differential equations that can accurately model the random behavior of the neutron density and the precursor concentrations in a point reactor. Due to the stiffness of these equations, this system was numerically implemented using a stochastic piecewise constant approximation method (Stochastic PCA). Here, we present a study of the influence of stochastic fluctuations on the results of the neutron point kinetics equation. We reproduce the stochastic formulation introduced by Hayes and Allen and compute Monte Carlo numerical results for examples with constant and time-dependent reactivity, comparing these results with stochastic and deterministic methods found in the literature. Moreover, we introduce a modified version of the stochastic method to obtain a non-stiff solution, analogue to a previously derived deterministic approach. (author)

Extraction of the neutron-neutron scattering length ann from kinematically complete neutron-deuteron breakup experiments

International Nuclear Information System (INIS)

Witala, H.; Hueber, D.; Gloeckle, W.; Tornow, W.; Gonzalez Trotter, D.E.

1996-01-01

Data for the neutron-neutron final-state-interaction cross section obtained recently in a kinematically complete neutron-deuteron breakup experiment have been reanalyzed using rigorous solutions of the three-nucleon Faddeev equations with realistic nucleon-nucleon interactions. A discrepancy was found with respect to a recent analysis based on the W-matrix approximation to the Paris potential. We also estimate theoretical uncertainties in extracting the neutron-neutron scattering length resulting from the use of different nucleon-nucleon interactions and the possible action of the two pion-exchange three-nucleon force. We find that there exists a certain production angle for the interacting neutron-neutron pair where the uncertainties become minimal. (author)

Black-spot poison ivy.

Science.gov (United States)

Schram, Sarah E; Willey, Andrea; Lee, Peter K; Bohjanen, Kimberly A; Warshaw, Erin M

2008-01-01

In black-spot poison ivy dermatitis, a black lacquerlike substance forms on the skin when poison ivy resin is exposed to air. Although the Toxicodendron group of plants is estimated to be the most common cause of allergic contact dermatitis in the United States, black-spot poison ivy dermatitis is relatively rare.

Poisoning first aid

Science.gov (United States)

... page: //medlineplus.gov/ency/article/007579.htm Poisoning first aid To use the sharing features on this page, ... burns Stupor Unconsciousness (coma) Unusual breath odor Weakness First Aid Seek immediate medical help. For poisoning by swallowing ...

Isopropanol alcohol poisoning

Science.gov (United States)

Rubbing alcohol poisoning; Isopropyl alcohol poisoning ... Isopropyl alcohol can be harmful if it is swallowed or gets in the eyes. ... These products contain isopropanol: Alcohol swabs Cleaning supplies ... Rubbing alcohol Other products may also contain isopropanol.

Hydrochloric acid poisoning

Science.gov (United States)

Hydrochloric acid is a clear, poisonous liquid. It is highly corrosive, which means it immediately causes severe damage, such ... poisoning due to swallowing or breathing in hydrochloric acid. This article is for information only. Do NOT ...

On progress of the solution of the stationary 2-dimensional neutron diffusion equation: a polynomial approximation method with error analysis

International Nuclear Information System (INIS)

Ceolin, C.; Schramm, M.; Bodmann, B.E.J.; Vilhena, M.T.

2015-01-01

Recently the stationary neutron diffusion equation in heterogeneous rectangular geometry was solved by the expansion of the scalar fluxes in polynomials in terms of the spatial variables (x; y), considering the two-group energy model. The focus of the present discussion consists in the study of an error analysis of the aforementioned solution. More specifically we show how the spatial subdomain segmentation is related to the degree of the polynomial and the Lipschitz constant. This relation allows to solve the 2-D neutron diffusion problem for second degree polynomials in each subdomain. This solution is exact at the knots where the Lipschitz cone is centered. Moreover, the solution has an analytical representation in each subdomain with supremum and infimum functions that shows the convergence of the solution. We illustrate the analysis with a selection of numerical case studies. (author)

On progress of the solution of the stationary 2-dimensional neutron diffusion equation: a polynomial approximation method with error analysis

Energy Technology Data Exchange (ETDEWEB)

Ceolin, C., E-mail: celina.ceolin@gmail.com [Universidade Federal de Santa Maria (UFSM), Frederico Westphalen, RS (Brazil). Centro de Educacao Superior Norte; Schramm, M.; Bodmann, B.E.J.; Vilhena, M.T., E-mail: celina.ceolin@gmail.com [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica

2015-07-01

Recently the stationary neutron diffusion equation in heterogeneous rectangular geometry was solved by the expansion of the scalar fluxes in polynomials in terms of the spatial variables (x; y), considering the two-group energy model. The focus of the present discussion consists in the study of an error analysis of the aforementioned solution. More specifically we show how the spatial subdomain segmentation is related to the degree of the polynomial and the Lipschitz constant. This relation allows to solve the 2-D neutron diffusion problem for second degree polynomials in each subdomain. This solution is exact at the knots where the Lipschitz cone is centered. Moreover, the solution has an analytical representation in each subdomain with supremum and infimum functions that shows the convergence of the solution. We illustrate the analysis with a selection of numerical case studies. (author)

Mercurial poisoning

Energy Technology Data Exchange (ETDEWEB)

Gorton, B

1924-01-01

Cats which had been kept in a thermometer factory to catch rats were afflicted with mercury poisoning. So were the rats they were supposed to eat. The symptoms of mercury poisoning were the same in both species. The source of mercury for these animals is a fine film of the metal which coats floors, a result of accidental spills during the manufacturing process.

Neutrons moderation theory; Theorie du ralentissement des neutrons

Energy Technology Data Exchange (ETDEWEB)

Vigier, J P

1949-07-01

This report gives a summarized presentation of the theory of fast neutrons diffusion and moderation in a given environment as elaborated by M. Langevin, E. Fermi, R. Marshak and others. This statistical theory is based on three assumptions: there is no inelastic diffusion, the elastic diffusion has a spherical symmetry with respect to the center of gravity of the neutron-nucleus system (s-scattering), and the effects of chemical bonds and thermal agitation of nuclei are neglected. The first chapter analyzes the Boltzmann equation of moderation, its first approximate solution (age-velocity equation) and its domain of validity, the extension of the age-velocity theory (general solution) and the boundary conditions, the upper order approximation (spherical harmonics method and Laplace transformation), the asymptotic solutions, and the theory of spatial momenta. The second chapter analyzes the energy distribution of delayed neutrons (stationary and non-stationary cases). (J.S.)

Chelation Therapy for Mercury Poisoning

Directory of Open Access Journals (Sweden)

Rong Guan

2009-01-01

Full Text Available Chelation therapy has been the major treatment for heavy metal poisoning. Various chelating agents have been developed and tested for treatment of heavy metal intoxications, including mercury poisoning. It has been clearly shown that chelating agents could rescue the toxicity caused by heavy metal intoxication, but the potential preventive role of chelating agents against heavy metal poisoning has not been explored much. Recent paper by Siddiqi and colleagues has suggested a protective role of chelating agents against mercury poisoning, which provides a promising research direction for broader application of chelation therapy in prevention and treatment of mercury poisoning.

Optimization of Treatment Policy for Acute Carbon Monoxide Poisoning

Directory of Open Access Journals (Sweden)

R. N. Akalayev

2012-01-01

Full Text Available Objective: to evaluate the efficiency of combination use of hyperbaric oxygenation, succinate-containing solutions, and anti-edematous agents in patients with acute carbon monoxide poisoning. Subjects and methods. The results of treatment were analyzed in 32 patients admitted in 2009—2011 for severe acute carbon monoxide poisoning and a Glasgow coma score of 6—8. The patients were divided into 2 groups: 1 patients whose combination therapy involved hyperbaric oxygenation, Succinasol infusions, and L-lysine-aescinate injections; 2 those who received traditional therapy. All the patients underwent complex clinical, laboratory, and neurophysiologic examinations. Results. Just 24 hours after the combination use of Succinasol and L-lysine-aescinate, Group I patients were observed to have substantially reduced lactate, the content of the latter approached the normal value following 48 hours, which was much below the values in the control group. The similar pattern was observed when endogenous intoxication parameters were examined. During the performed therapy, the level of consciousness and that of intellect according to the MMSE and FAB scales were restored more rapidly in the study group patients than in Group 2. Conclusion. The combination use of hyperbaric oxygenation, the succinate-containing solution Succinasol, and the anti-edematous agent L-lysine-aescinate considerably enhances the efficiency of intensive therapy for acute carbon monoxide poisoning. Key words: carbon monoxide, toxic hypoxic encephalopathy, combination therapy, hyperbaric oxygenation, succinic acid, L-lysine-aescinate.

Extracorporeal treatment for thallium poisoning

DEFF Research Database (Denmark)

Ghannoum, Marc; Nolin, Thomas D; Goldfarb, David S

2012-01-01

The EXtracorporeal TReatments In Poisoning (EXTRIP) workgroup was formed to provide recommendations on the use of extracorporeal treatment (ECTR) in poisoning. To test and validate its methods, the workgroup reviewed data for thallium (Tl).......The EXtracorporeal TReatments In Poisoning (EXTRIP) workgroup was formed to provide recommendations on the use of extracorporeal treatment (ECTR) in poisoning. To test and validate its methods, the workgroup reviewed data for thallium (Tl)....

[Electronic poison information management system].

Science.gov (United States)

Kabata, Piotr; Waldman, Wojciech; Kaletha, Krystian; Sein Anand, Jacek

2013-01-01

We describe deployment of electronic toxicological information database in poison control center of Pomeranian Center of Toxicology. System was based on Google Apps technology, by Google Inc., using electronic, web-based forms and data tables. During first 6 months from system deployment, we used it to archive 1471 poisoning cases, prepare monthly poisoning reports and facilitate statistical analysis of data. Electronic database usage made Poison Center work much easier.

Pyrolytic Graphite as a Tunable Second order Neutron Filter

International Nuclear Information System (INIS)

Adib, M.

2009-01-01

A study has been carried out on the neutron transmission through pyrolytic graphite (PG) crystals in order to check its applicability as an efficient tunable second order neutron filter. The neutron transmission have been calculated as a function of neutron wavelengths in the range from 0.01 nm up to 0.7 nm at various PG mosaic spread, thickness and orientation of its c-axis with respect to the beam direction The Computer package Graphite has been used to provide the required calculation. It was shown that highly aligned (10 FWHM on mosaic spread) PG crystal ∼2 cm thick, may be tuned for optimum scattering of 2 second order neutrons within some favorable wavelength intervals in the range between 0.112 and 0.425 nm by adjusting the crystal in an appropriate orientation. .However, a less quality and thinner PG was found to almost eliminate 2 second order neutrons at only tuned values of wavelength corresponding to the poison of the triple intersection points of the curves (hkl) ± and (00l)

Carbon Monoxide Poisoning

Directory of Open Access Journals (Sweden)

Kamal Mishra

2016-01-01

Full Text Available Introduction: Carbon monoxide is known as the silent killer, being colorless, odourless, and tasteless. Initially non-irritating, it is very difficult for people to detect Carbon monoxide is a product of incomplete combustion of organic matter due to insufficient oxygen supply that prevents complete oxidation of carbon to C02. During World War II, Nazis used gas vans to kill an estimated over 700,000 prisoners by carbon monoxide poisoning. This method was also used in the gas chambers ofseveral death camps. The true number of incidents of carbon monoxide poisoning is unknown, since many non-lethal exposures go undetected From the available data, carbon monoxide poisoning is the most common cause of injury and death due to poisoning worldwide. Clinical features and management: The signs of carbon monoxide poisoning vary with concentration and length of exposure. Subtle cardiovascular or neurobehavioural effects occur at low concentration. The onset of chronic poisoning is usually insidious and easily mistaken for viral prodrome, depression, or gastroenteritis in children. The classic sign of carbon monoxide poisoning which is actually more often seen in the dead than the living is appearing red-cheeked and healthy. Cherry pink colour develops in nails, skin and mucosa. In acute poisoning, common abnormalities of posture and tone are cogwheel rigidity, opisthotonus, spasticity or flaccidity and seizures. Retinal haemorrhages and the classic cherry red skin colour are seldom seen. Different people andpopulations may have different carbon monoxide tolerance levels. On average, exposures at 100ppm or greater is dangerous to human health. Treatment and prevention: The mainstay of treatment is 100% oxygen administration until the COHb level is normal When the patient is stable enough to be transported, hyperbaric oxygen (HBOT should be considered This treatment is safe and well tolerated Public education about the danger of carbon monoxide, with

Successful treatment of polymedicamentous poisoning with metoprolol, diltiazem and cilazapril

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Radovanović Milan R.

2009-01-01

Full Text Available Introduction. Poisoning caused by drugs with cardiodepressive effects is an urgent condition in medicine which is associated with high mortality rate regardless of modern therapeutic methods. Accidental or intentional poisoning whit these drugs produces heart activity depression and cardiovascular collapse as consequences. Current therapy for severe poisoning caused by beta-blockers and calcium channel blockers includes both unspecific and specific antidote therapy whit glucagon, as well as application of adrenergic drugs, calcium, phosphodiesterase inhibitors and hyperinsulinemia/euglycemia therapy. However, even whit the application of these drugs, prompt measures of unspecific detoxication therapy and cardiopulmonary reanimation are crucial for survival of patients with severe poisoning. Case report. A 28-year-old female patient was hospitalized for cardiogenic shock and altered state of conscioussnes (Glasgow coma score = 4, caused by acute poisoning with 2 g of metoprolol (Presolol®, 1.8 g of diltiazem (Cortiazem® and 50 mg of cilazapril (Zobox®. Prolonged cardiopulmonary resuscitation was applied during the first 16 hours of hospitalization, including administration of crystaline solutions (8 L, 17 mg of adrenaline, 4 mg of atropine, 4 mg of glucagone and 1.6 g of dopamine, with electro-stimulation by temporary pacemaker and mechanical ventilation. In a defined time period, normalized state of consciousness was registered, mechanical ventilation was stopped and normal heart activity and hemodynamic stability were accomplished. During hospitalization the patient was treated for mild pneumonia and after ten days, completely recovered, was released and sent to home treatment. Conclusion. Prompt measures of cardiopulmonary resuscitation and multidisciplinary treatment in intensive care units significantly increase the chances of complete recovery of a patient with severe poisoning caused by drugs with cardiodepressive efects.

On the neutronics of spent fuel storage pools

International Nuclear Information System (INIS)

Caro, R.; Martinez-Val, J.M.; Donoso, E.

1980-01-01

The neutron physics of light-water-reactor fuel elements storage is analyzed for reviewing the calculation methodologies and pointing out its characteristics, specially those related to the safety analysis report. Some numerical results are presented, involving both clean and poisoned storage pools. Besides the conventional criticality calculations in nominal and accidental circumstances, the so-called optimum moderation phenomenon is dealt with special emphasis. (author)

Amnesic Shellfish Poisoning

Science.gov (United States)

... Since then, the death or stranding of other marine animals, including whales, has been suspected or confirmed to ... sickened or die due to domoic acid poisoning. Animals poisoned by domoic acid include seabirds and marine mammals, including sea lions, sea otters, whales. Domoic- ...

Lithium Poisoning

DEFF Research Database (Denmark)

Baird-Gunning, Jonathan; Lea-Henry, Tom; Hoegberg, Lotte C G

2017-01-01

Lithium is a commonly prescribed treatment for bipolar affective disorder. However, treatment is complicated by lithium's narrow therapeutic index and the influence of kidney function, both of which increase the risk of toxicity. Therefore, careful attention to dosing, monitoring, and titration...... is required. The cause of lithium poisoning influences treatment and 3 patterns are described: acute, acute-on-chronic, and chronic. Chronic poisoning is the most common etiology, is usually unintentional, and results from lithium intake exceeding elimination. This is most commonly due to impaired kidney...... function caused by volume depletion from lithium-induced nephrogenic diabetes insipidus or intercurrent illnesses and is also drug-induced. Lithium poisoning can affect multiple organs; however, the primary site of toxicity is the central nervous system and clinical manifestations vary from asymptomatic...

Numerical Solution of Fractional Neutron Point Kinetics Model in Nuclear Reactor

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Nowak Tomasz Karol

2014-06-01

Full Text Available This paper presents results concerning solutions of the fractional neutron point kinetics model for a nuclear reactor. Proposed model consists of a bilinear system of fractional and ordinary differential equations. Three methods to solve the model are presented and compared. The first one entails application of discrete Grünwald-Letnikov definition of the fractional derivative in the model. Second involves building an analog scheme in the FOMCON Toolbox in MATLAB environment. Third is the method proposed by Edwards. The impact of selected parameters on the model’s response was examined. The results for typical input were discussed and compared.

Numerical solution of neutron transport equations in discrete ordinates and slab geometry

International Nuclear Information System (INIS)

Serrano Pedraza, F.

1985-01-01

in developing of this work are presented. In Appendix B a general list of computer program is given, in Appendix C analytical solutions for two simple problems are presented and finally in appendix D some concepts and definitions about numerical stability are given. It can also be mentioned that computer code has no limitation with to number of regions and number of energy groups. Furnishing cross sections, the computer program gives the following results. 1) Angular flux when a problem with independent source without fissions are considered, 2) number of secondary neutrons for collition or 3) effective multiplication factor (Author)

Critical experiment program of heterogeneous core composed for LWR fuel rods and low enriched uranyl nitrate solution

International Nuclear Information System (INIS)

Miyoshi, Yoshinori; Yamamoto, Toshihiro; Watanabe, Shouichi; Nakamura, Takemi

2003-01-01

In order to stimulate the criticality characteristics of a dissolver in a reprocessing plant, a critical experiment program of heterogeneous cores is under going at a Static Critical Experimental Facility, STACY in Japan Atomic Energy Research Institute, JAERI. The experimental system is composed of 5w/o enriched PWR-type fuel rod array immersed in 6w/o enriched uranyl nitrate solution. First series of experiments are basic benchmark experiments on fundamental critical data in order to validate criticality calculation codes for 'general-form system' classified in the Japanese Criticality Safety Handbook, JCSHB. Second series of experiments are concerning the neutron absorber effects of fission products related to the burn-up credit Level-2. For demonstrating the reactivity effects of fission products, reactivity effects of natural elements such as Sm, Nd, Eu and 103 Rh, 133 Cs, solved in the nitrate solution are to be measured. The objective of third series of experiments is to validate the effect of gadolinium as a soluble neutron poison. Properties of temperature coefficients and kinetic parameters are also studied, since these parameters are important to evaluate the transient behavior of the criticality accident. (author)

Neutron diffraction studies on Ca1− xBaxZr4P6O24 solid solutions

Indian Academy of Sciences (India)

P6O24 compositions from combined Rietveld refinements of powder X-ray and neutron diffraction data. All the studied compositions crystallize in rhombohedral lattice (space group R-3 No. 148). A continuous solid solution is concluded from ...

Phosphorus poisoning in waterfowl

Science.gov (United States)

Coburn, D.R.; DeWitt, J.B.; Derby, J.V.; Ediger, E.

1950-01-01

Black ducks and mallards were found to be highly susceptible to phosphorus poisoning. 3 mg. of white phosphorus per kg. of body weight given in a single dose resulted in death of a black duck in 6 hours. Pathologic changes in both acute and chronic poisoning were studied. Data are presented showing that diagnosis can be made accurately by chemical analysis of stored tissues in cases of phosphorus poisoning.

Carbon Monoxide (CO) Poisoning Prevention

Science.gov (United States)

... family by acting wisely in case of a power outage and learning the symptoms of CO poisoning. How to Recognize CO Poisoning The most common symptoms of CO poisoning are headache, dizziness, weakness, nausea, vomiting, chest pain, and confusion. People who are sleeping or who ...

What is the definition of a poisoning?

Science.gov (United States)

Uges, D R

2001-03-01

New insights in medicine and acceptable treatments necessitates an adjustment of the existing definition of clinical or forensic poisoning to: 'An individual's medical or social unacceptable condition as a consequence of being under influence of an exogenous substance in a dose too high for the person concerned'. For medical and legal purposes it is important to know how the victim became poisoned. In general, there are three ways of causing medical poisoning: accidental poisoning, including iatrogenic poisoning, experimental and intentional poisoning. Nowadays iatrogenic intoxication, poisoning caused by the Münchhausen's syndrome (by proxy) and experimental poisoning (designer drugs) have a major place in contemporary toxicology. Although some toxicologists use the word 'intoxication' only overdoses with central effects, in this article 'intoxication' and 'poisoning' are considered to be synonymous.

Determination of boron in water solution by an indirect neutron activation technique from a 241Am/Be source

International Nuclear Information System (INIS)

Sales, H.B.

1981-08-01

Boron content in water solutions has been analysed by Indirect Activation Technique a twin 241 Am/Be neutron source with a source strength of 9x10 6 n/seg. The boron concentration was inferred from the measurement of the activity induced in a vanadium flux monitor. The vanadium rod was located inside the boron solution in a standart geometrical set up with respect to the neutron source. Boron concentrations in the range of 100 to 1000 ppm were determined with an overall accuracy of about 2% during a total analysis time of about 20 minutes. Eventhough the analysis is not selective for boron yet due the rapid, simple and precise nature, it is proposed for the analysis of boron in the primary coolant circuit of Nuclear Power Plants of PWR type. (Author) [pt

A Rare but Potentially Fatal Poisoning; Aluminum Phosphide Poisoning

Directory of Open Access Journals (Sweden)

Orkun Tolunay

2017-04-01

Full Text Available Phosphide, a very toxic gas, is used in our country as aluminium phosphide tablets impregnated in clay. It is widely used since it has a very high diffusion capacity, whereby it can eradicate all living creatures in any form of their life cycle and does not leave any remnants in agricultural products. Aluminum phosphide poisoning is among intoxications for which there are still no true antidotes. Mortality rate varies between 30% and 100%. This paper presents a case of aluminum phosphide poisoning caused by the uncompleted suicide attempt. A 14-year-old girl, who swallowed aluminum phosphate tablets, was brought to the emergency department with the complaints of nausea and vomiting. The patient was treated with gastric lavage and activated charcoal. Since the patient ingested a lethal amount of aluminum phosphide, she was referred to the pediatric intensive care unit. The patient was discharged in stable condition after supportive care and monitoring. Specific antidotes are life-saving in poisonings. However, this case was presented to show how general treatment principles and quick access to health services affect the result of treatment. Also, we aimed to highlight the uncontrolled selling of aluminum phosphate, which results in high mortality rates in case of poisoning.

Poisoning - Multiple Languages

Science.gov (United States)

... Well-Being 6 - Poison Safety - Amarɨñña / አማርኛ (Amharic) MP3 Siloam Family Health Center Arabic (العربية) Expand Section ... Well-Being 6 - Poison Safety - myanma bhasa (Burmese) MP3 Siloam Family Health Center Dari (دری) Expand Section ...

49 CFR 172.430 - POISON label.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false POISON label. 172.430 Section 172.430... SECURITY PLANS Labeling § 172.430 POISON label. (a) Except for size and color, the POISON label must be as follows: EC02MR91.029 (b) In addition to complying with § 172.407, the background on the POISON label must...

49 CFR 172.554 - POISON placard.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false POISON placard. 172.554 Section 172.554... SECURITY PLANS Placarding § 172.554 POISON placard. (a) Except for size and color, the POISON placard must be as follows: EC02MR91.057 (b) In addition to complying with § 172.519, the background on the POISON...

Solution of the linearly anisotropic neutron transport problem in a infinite cylinder combining the decomposition and HTSN methods

International Nuclear Information System (INIS)

Goncalves, Glenio A.; Bodmann, Bardo; Bogado, Sergio; Vilhena, Marco T.

2008-01-01

Analytical solutions for neutron transport in cylindrical geometry is available for isotropic problems, but to the best of our knowledge for anisotropic problems are not available, yet. In this work, an analytical solution for the neutron transport equation in an infinite cylinder assuming anisotropic scattering is reported. Here we specialize the solution, without loss of generality, for the linearly anisotropic problem using the combined decomposition and HTS N methods. The key feature of this method consists in the application of the decomposition method to the anisotropic problem by virtue of the fact that the inverse of the operator associated to isotropic problem is well know and determined by the HTS N approach. So far, following the idea of the decomposition method, we apply this operator to the integral term, assuming that the angular flux appearing in the integrand is considered to be equal to the HTS N solution interpolated by polynomial considering only even powers. This leads to the first approximation for an anisotropic solution. Proceeding further, we replace this solution for the angular flux in the integral and apply again the inverse operator for the isotropic problem in the integral term and obtain a new approximation for the angular flux. This iterative procedure yields a closed form solution for the angular flux. This methodology can be generalized, in a straightforward manner, for transport problems with any degree of anisotropy. For the sake of illustration, we report numerical simulations for linearly anisotropic transport problems. (author)

Radiolysis of some aqueous solutions of neutron absorbers; Etude des effets de certains absorbeurs de neutrons en solution sur la radiolyse de l'eau

Energy Technology Data Exchange (ETDEWEB)

Rozenberg, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1964-12-15

The initial yield of molecular hydrogen formed by radiolytic decomposition of water in reactor and {sup 60}Co gamma radiation is decreased by the presence of salts of polyvalent elements possessing only one stable valence, i.e cadmium, zinc, magnesium, gadolinium. This effect is favourable for the use of cadmium and gadolinium as soluble neutron absorber in heavy water reactors. Cations of these salts are not inert toward the primary products of water radiolysis. They have a high degree of reactivity toward the hydrated electron, which is the precursor of molecular hydrogen in neutral or alkaline aqueous media. The value of the rate constant for the reaction between cadmium ion and hydrated electron was shown to be (6.1 {+-} 1.8) 10{sup 10} M{sup -1} s{sup -1}. Boric acid at low concentration has no effect on the radiation chemistry of water. An isotope effect has been found in the radiolysis of heavy water, corresponding to a lowering of initial yield [G{sub 0}(D{sub 2}) < G{sub 0}(H{sub 2})]. additionally it was necessary to determine the influence of organic impurities, remaining after the purification of water, on the mechanism of its radiolytic decomposition. (author) [French] Le rendement initial de la formation d'hydrogene moleculaire dans la decomposition radiolytique de l'eau, sous l'effet du rayonnement des reacteurs nucleaires ou du cobalt 60, est diminue si le solute est un sel d'element polyvalent ne possedant qu'un seul etat stable de valence (cadmium, zinc, magnesium, gadolinium). Cet effet est favorable au choix des elements cadmium et gadolinium pour servir d'absorbeur soluble de neutrons dans un reacteur a eau lourde. Les cations de ces sels ne sont pas inertes vis-a-vis des produits primaires de la radiolyse. Ils ont une affinite notable pour l'electron solvate, precurseur de l'hydrogene moleculaire en milieu neutre ou alcalin. En particulier, la constante de vitesse de la reaction du cadmium ionise avec l'electron solvate a pu etre calculee. Sa

A solution of the thermal neutron diffusion equation for a two-region cyclindrical system program for ODRA-1305 computer

International Nuclear Information System (INIS)

Drozdowicz, K.; Woznicka, U.

1982-01-01

The program in FORTRAN for the ODRA-1305 computer is described. The dependence of the decay constant of the thermal neutron flux upon the dimensions of the two-region concentric cylindrical system is the result of the program. The solution (with a constant neutron flux in the inner medium assumed) is generally obtained in the one-group diffusion approximation by the method of the perturbation calculation. However, the energy distribution of the thermal neutron flux and the diffusion cooling are taken into account. The program is written for the case when the outer medium is hydrogenous. The listing of the program and an example of calculation results are included. (author)

Optimizing the use of gadolinium as burnable poison in nuclear fuel: towards a boron free PWR

International Nuclear Information System (INIS)

Pieck, D.

2013-01-01

Reactivity excess in Nuclear Power Plants is controlled by reactor's active systems: boric acid dilution and control rods. Alternatively, negative reactivity insertion can be made in a passive way using burnable poisons, i.e. neutron absorbers, this is the case of gadolinium (Gd). In the industrial framework of U 235 enrichment increase and boric acid restraint, the goal of this thesis is to optimize the distribution of gadolinium in UO 2 ceramics to obtain a high-performance provision of negative reactivity in Pressurized Water Reactors. In this sense, the work is focus on new gadolinium-rich materials. Thus, U-Gd-O phase diagram was explored in the field of high Gd contents. Two cubic phases were found and characterized: the C1 and C2 phases. With the aim of an industrial application, C1 phase was selected as candidate for Gd addition into UO 2 pellets. The optimal distribution of C1 phase within a nuclear fuel assembly was studied using APOLLO 2.8 neutron transport code. Parametric calculations were performed. These neutronic studies have ends in a successful 'concept of poisoned pellet'. Finally, some prototype pellets following this concept were made in laboratory to proof it feasibility. All the obtained results shows that the proposed concept of a neutro-phage C1-phase coating on UO 2 pellets is a convenient way to reduce reactivity excess within the framework of long irradiation cycles. This concept could be potentially applied in industrial scale. Consequently a patent application process was initiated.(author) [fr

Structure of polyacrylic acid and polymethacrylic acid solutions : a small angle neutron scattering study

OpenAIRE

Moussaid , A.; Schosseler , F.; Munch , J.; Candau , S.

1993-01-01

The intensity scattered from polyacrylic acid and polymethacrylic acid solutions has been measured by small angle neutron scattering experiemnts. The influence of polymer concentration, ionization degree, temperature and salt content has been investigated. Results are in qualitative agreement with a model which predicts the existence of microphases in the unstable region of the phase diagram. Quantitative comparison with the theory is performed by fitting the theoretical structure factor to t...

Extracorporeal treatment for barbiturate poisoning

DEFF Research Database (Denmark)

Mactier, Robert; Laliberté, Martin; Mardini, Joelle

2014-01-01

The EXTRIP (Extracorporeal Treatments in Poisoning) Workgroup conducted a systematic review of barbiturate poisoning using a standardized evidence-based process to provide recommendations on the use of extracorporeal treatment (ECTR) in patients with barbiturate poisoning. The authors reviewed all...... treatment should be continued during ECTR. (4) Cessation of ECTR is indicated when clinical improvement is apparent. This report provides detailed descriptions of the rationale for all recommendations. In summary, patients with long-acting barbiturate poisoning should be treated with ECTR provided at least......-acting barbiturates are dialyzable and short-acting barbiturates are moderately dialyzable. Four key recommendations were made. (1) The use of ECTR should be restricted to cases of severe long-acting barbiturate poisoning. (2) The indications for ECTR in this setting are the presence of prolonged coma, respiratory...

Bubble bath soap poisoning

Science.gov (United States)

... medlineplus.gov/ency/article/002762.htm Bubble bath soap poisoning To use the sharing features on this page, please enable JavaScript. Bubble bath soap poisoning occurs when someone swallows bubble bath soap. ...

Limitations for qualitative and quantitative neutron activation analysis using reactor neutrons

International Nuclear Information System (INIS)

El-Abbady, W.H.; El-Tanahy, Z.H.; El-Hagg, A.A.; Hassan, A.M.

1999-01-01

In this work, the most important limitations for qualitative and quantitative analysis using reactor neutrons for activation are reviewed. Each limitation is discussed using different examples of activated samples. Photopeak estimation, nuclear reactions interference and neutron flux measurements are taken into consideration. Solutions for high accuracy evaluation in neutron activation analysis applications are given. (author)

Structure and dynamics of nonaqueous electrolyte solutions by small angle neutron scattering, brownian dynamics and primitive model theories

International Nuclear Information System (INIS)

Kunz, W.; Turq, P.

1990-01-01

The study of electrolyte solutions by small angle neutron scattering (static) of quasi-elastic neutron scattering (dynamics) gives new perspectives to the primitive model of electrolytes, for both static and dynamic properties of those systems. Whereas all properties can be interpreted by brownian dynamics, integral equations cannot be used at the present time to get transport coefficients in all cases. As regards the choice of the potentials at the McMillan Mayer level, specific Gurney terms for solvation are not needed for tetraalkylammonium salts. (orig.)

CIGUATERA POISONING: PACIFIC DISEASE, FOODBORNE POISONING FROM FISH IN WARM SEAS AND OCEANS. Review

Directory of Open Access Journals (Sweden)

Snezha Zlateva

2017-02-01

Full Text Available Purpose: The review is provoked because of lack of awareness of the medical practitioners in Bulgaria concerning of the ethnology, pathogenesis, clinical symptoms and treatment of the ciguatera fish poisoning (CFP. This can be a source of prolonged diagnostic delays, as some cases reporting in another country in Europe, for example Germany, Spain and UK. Varna is the sea town with many sailor crews returning from tropical and subtropical regions, or CFP can affect people who travel to the Pacific and Caribbean or ate exotic fish from supermarket. The information of this fish food-borne poisoning is part of student’s education in discipline “Marine medicine” in Medical University, Varna. Materials and methods: To present better information from different authors and last scientific data, we made review of published materials of 58 issues to construct definition, history, etiology, pathogenesis (toxins and mechanisms of action, clinical symptoms, treatment and prevention of the Ciguatera or ichtyosarcotoxicosis, a wide spread food-born poisoning. Results: Ciguatera poisoning is ichtyosarcotoxicosis, a wide-spread foodborne poisoning in people after consumption of flesh of different kinds of fishes in which toxins produced by poisonous microorganisms (Dinoflagellates have accumulated. The poisoning develops by accumulating toxins higher up the food chain starting with toxin producing dinoflagellates (species: Gambierdiscus toxicus, Prorocentrum concavum, Pr. lima, Ostreoposis lenticularis, Ostr. Siamensis and others, continuing with the poisoned algae (species: Portieria, Halymenia, Turbinaria, Sargassum, and after that involving small crustacea and small fishes to greater fishes (vector fishes, genus Herbivores and Carnivores, in which the toxins have been stored in amount, great enough to cause foodborne poisoning in humans. This poisoning is widespread in tropical and subtropical regions, but because of its delayed toxic effects, lasting

Studying the effect of xenon poisoning on the power of the Syrian miniature neutron source reactor

International Nuclear Information System (INIS)

Khamis, I.; Khattab, K.

1999-07-01

The uranium 235 is often used as a fuel to produce the energy in nuclear reactors. Uranium nuclei are fissioned with thermal neutrons and produce energy plus a number of neutrons. A fraction of such fission neutrons is involved in other fission with new nuclei to sustain the fission reactions. The remain fraction of the neutrons is lost from the reactor in two ways: escaped from the reactor, or absorbed with other nuclei that exist in the reactor before or produced from fission. Fission nuclei which absorb neutrons heavily are called p oison , such as Xe 135. Because Xe 135 absorbs neutrons heavily, it reduces the number of neutrons in the reactor. Hence, Xe 135 is studied explicitly in the MNSR reactor, and calculation of its negative reactivity is presented in this research during the operation, equilibrium, and after the shutting down of the reactor. (author)

Hydration of the chloride ion in concentrated aqueous solutions using neutron scattering and molecular dynamics

Czech Academy of Sciences Publication Activity Database

Pluhařová, Eva; Fischer, H. E.; Mason, Philip E.; Jungwirth, Pavel

2014-01-01

Roč. 112, 9/10 (2014), s. 1230-1240 ISSN 0026-8976 R&D Projects: GA ČR GBP208/12/G016; GA MŠk LH12001 Grant - others:GA MŠk(CZ) LM2010005 Institutional support: RVO:61388963 Keywords : lithium * solution * molecular dynamics * chloride * neutron scattering Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.720, year: 2014

[Suicidal poisoning with benzodiazepines].

Science.gov (United States)

Chodorowski, Z; Sein Anand, J

1997-01-01

In the period from 1987 to 1996, 103 patients with suicidal benzodiazepines poisoning were treated, including 62 women and 41 men from 16 to 79 (mean 34) years old. 23 persons were poisoned only by benzodiazepines, in 80 remaining cases intoxications were mixed eg. including benzodiazepines and alcohol, tricyclic antidepressants, barbiturates, opioids, phenothiazines. The main causes of suicides were mainly depression, drug addiction and alcoholism. Nobody died in the benzodiazepines group, while mortality rate in the group of mixed poisoning was 4%. Prescribing benzodiazepines by physicians was quite often not justified and facilitated, among others, accumulation of the dose sufficient for suicide attempt. Flumazenil was efficient for leading out from coma in 86% of cases with poisoning only by benzodiazepines and 13% of cases with mixed intoxications mainly containing benzodiazepines and alcohol or carbamazepine.

Poison 1 - a programme for calculation of reactivity transients due to fission product poisoning and its application in continuous determination of xenon and samarium poisoning in reactor KS-150

International Nuclear Information System (INIS)

Rana, S.B.

1973-12-01

The report contains a user's description of the 3-dimensional programme POISON 1 for calculating reactivity transients due to fission-product poisoning during changes of reactor power. The chapter dealing with Xe poisoning contains a description of Xe tables, the method of operational determination of Xe poisoning, use of Xe transients for calibrating control rods and means of shutting down the reactor without being overriden by Xe poisoning. Sm poisoning is determined continuously on the basis of the power diagram of reactor operation. In conclusion a possibility of using the programme in a process computer in combination with self-powered detectors as local power sensors is indicated. (author)

Oil-based paint poisoning

Science.gov (United States)

Paint - oil-based - poisoning ... Hydrocarbons are the primary poisonous ingredient in oil paints. Some oil paints have heavy metals such as lead, mercury, cobalt, and barium added as pigment. These heavy metals can cause additional ...

Poison exposures in young Israeli military personnel: a National Poison Center Data analysis.

Science.gov (United States)

Lavon, Ophir; Bentur, Yedidia

2017-06-01

To characterize poison exposures in young Israeli military personnel as reported to the national poison center. Retrospective poison center chart review over a 14-year period. Cases included were Israeli soldiers aged 18-21 years, the compulsory military service age required by the Israeli law. 1770 records of poison exposures in young military personnel were identified. Most exposed individuals involved males (n = 1268, 71.6%). Main routes of exposure were ingestion (n = 854, 48.3%), inhalation (n = 328, 18.6%) and ocular (n = 211, 11.9%). Accidents or misuse (n = 712, 40.2%) were the most frequently reported circumstances, followed by suicide attempts (370, 20.9%), and bites and stings (161, 9.1%). More than half of the cases involved chemicals (n = 939, 53.1%); hydrocarbons, gases and corrosives were the main causative agents. Pharmaceuticals (mainly analgesics) were involved in 519 (29.3%) cases, venomous animals (mainly scorpions, centipedes, and snakes) in 79 (4.5%). Clinical manifestations were reported in 666 (37.6%) cases, mostly gastrointestinal, neurologic, and respiratory. The vast majority of cases (1634, 92.3%) were asymptomatic or mildly affected; no fatalities were recorded. In 831 (46.9%) cases the clinical toxicologist recommended referral to an emergency department; ambulatory observation was recommended in 563 (31.8%) cases, and hospitalization in 86 (4.9%). Our data show that poison exposures among young soldiers involve mainly males, accidents, misuse and suicides, oral route and chemicals; most exposures were asymptomatic or with mild severity. Repeated evaluations of poison center data pertaining to military personnel is advised for identifying trends in poison exposure and characteristics in this particular population.

Analytical solution of neutron transport equation in an annular reactor with a rotating pulsed source; Resolucao analitica da equacao de transporte de neutrons em um reator anelar com fonte pulsada rotativa

Energy Technology Data Exchange (ETDEWEB)

Teixeira, Paulo Cleber Mendonca

2002-12-01

In this study, an analytical solution of the neutron transport equation in an annular reactor is presented with a short and rotating neutron source of the type S(x) {delta} (x- Vt), where V is the speed of annular pulsed reactor. The study is an extension of a previous study by Williams [12] carried out with a pulsed source of the type S(x) {delta} (t). In the new concept of annular pulsed reactor designed to produce continuous high flux, the core consists of a subcritical annular geometry pulsed by a rotating modulator, producing local super prompt critical condition, thereby giving origin to a rotating neutron pulse. An analytical solution is obtained by opening up of the annular geometry and applying one energy group transport theory in one dimension using applied mathematical techniques of Laplace transform and Complex Variables. The general solution for the flux consists of a fundamental mode, a finite number of harmonics and a transient integral. A condition which limits the number of harmonics depending upon the circumference of the annular geometry has been obtained. Inverse Laplace transform technique is used to analyse instability condition in annular reactor core. A regenerator parameter in conjunction with perimeter of the ring and nuclear properties is used to obtain stable and unstable harmonics and to verify if these exist. It is found that the solution does not present instability in the conditions stated in the new concept of annular pulsed reactor. (author)

Lead poisoning in dogs

Energy Technology Data Exchange (ETDEWEB)

Wilson, M R; Lewis, G

1963-08-03

Within a short period, 14 cases of lead poisoning in the dogs have been encountered. A detailed record appears justified as no published reference can be found to this condition occurring in Britain and because reports from other countries stress the similarity of the clinical manifestations of lead poisoning to those of the common infections of the dog. Five of the 14 clinical cases of lead poisoning are described. The available literature is reviewed and the diagnosis and significance of the condition discussed. 19 references, 2 tables.

Aggregation in concentrated protein solutions: Insights from rheology, neutron scattering and molecular simulations

Science.gov (United States)

Castellanos, Maria Monica

Aggregation of therapeutic proteins is currently one of the major challenges in the bio-pharmaceutical industry, because aggregates could induce immunogenic responses and compromise the quality of the product. Current scientific efforts, both in industry and academia, are focused on developing rational approaches to screen different drug candidates and predict their stability under different conditions. Moreover, aggregation is promoted in highly concentrated protein solutions, which are typically required for subcutaneous injection. In order to gain further understanding about the mechanisms that lead to aggregation, an approach that combined rheology, neutron scattering, and molecular simulations was undertaken. Two model systems were studied in this work: Bovine Serum Albumin in surfactant-free Phosphate Buffered Saline at pH = 7.4 at concentrations from 11 mg/mL up to ˜519 mg/mL, and a monoclonal antibody in 20 mM Histidine/Histidine Hydrochloride at pH = 6.0 with 60 mg/mL trehalose and 0.2 mg/mL polysorbate-80 at concentrations from 53 mg/mL up to ˜220 mg/mL. The antibody used here has three mutations in the CH2 domain, which result in lower stability upon incubation at 40 °C with respect to the wild-type protein, based on size-exclusion chromatography assays. This temperature is below 49 °C, where unfolding of the least stable, CH2 domain occurs, according to differential scanning calorimetry. This dissertation focuses on identifying the role of aggregation on the viscosity of protein solutions. The protein solutions of this work show an increase in the low shear viscosity in the absence of surfactants, because proteins adsorb at the air/water interface forming a viscoelastic film that affects the measured rheology. Stable surfactant-laden protein solutions behave as simple Newtonian fluids. However, the surfactant-laden antibody solution also shows an increase in the low shear viscosity from bulk aggregation, after prolonged incubation at 40 °C. Small

Control rods

International Nuclear Information System (INIS)

Hirukawa, Koji.

1979-01-01

Purpose: To ensure the fuel safety by constituting a control rod with a plurality of poison bodies suspended in a cross-like section and shorter length poison bodies made movable and engageable in the gap between each of the above poison bodies thereby maintaining the function of the shorter length poison constant. Constitution: Cross-like supports are secured to the upper and lower parts of a driving shaft journaled in a sheath and poison bodies composed of neutron absorber poisons of a large thermal neutron absorption cross section and neutron absorber poison tubes for containing them are suspended from the supports. A movable cross-like support is mounted slidably at its base to the lower part of the driving shaft and poison bodies shorter than the above poison bodies and composed of neutron absorber poisons having a greater absorption cross section at the neutron energy region higher than thermal neutron region and neutron poison tubes for containing them are suspended to the movable support at the position capable of engaging in the gap between each of the poison bodies. (Kawakami, Y.)

Solution of the neutron diffusion equation at two groups of energy by method of triangular finite elements

International Nuclear Information System (INIS)

Correia Filho, A.

1981-04-01

The Neutron Diffusion Equation at two groups of energy is solved with the use of the Finite - Element Method with first order triangular elements. The program EFTDN (Triangular Finite Elements on Neutron Diffusion) was developed using the language FORTRAN IV. The discrete formulation of the Diffusion Equation is obtained with the application of the Galerkin's Method. In order to solve the eigenvalue - problem, the Method of the Power is applied and, with the purpose of the convergence of the results, Chebshev's polynomial expressions are applied. On the solution of the systems of equations Gauss' Method is applied, divided in two different parts: triangularization of the matrix of coeficients and retrosubstitution taking in account the sparsity of the system. Several test - problems are solved, among then two P.W.R. type reactors, the ZION-1 with 1300 MWe and the 2D-IAEA - Benchmark. Comparision of results with standard solutions show the validity of application of the EFM and precision of the results. (Author) [pt

Diagnosis of acute poisoning

African Journals Online (AJOL)

Chantel

functional tissue damage in ... cury or alcohol) .... †The degree of poisoning, together with drug or poison levels, usually determines the .... monoxide, caffeine and the sym- .... the brain. It usually occurs when two or more drugs, which increase.

Solution and study of nodal neutron transport equation applying the LTS{sub N}-DiagExp method

Energy Technology Data Exchange (ETDEWEB)

Hauser, Eliete Biasotto; Pazos, Ruben Panta [Pontificia Univ. Catolica do Rio Grande do Sul, Porto Alegre, RS (Brazil). Faculdade de Matematica]. E-mail: eliete@pucrs.br; rpp@mat.pucrs.br; Vilhena, Marco Tullio de [Pontificia Univ. Catolica do Rio Grande do Sul, Porto Alegre, RS (Brazil). Instituto de Matematica]. E-mail: vilhena@mat.ufrgs.br; Barros, Ricardo Carvalho de [Universidade do Estado, Nova Friburgo, RJ (Brazil). Instituto Politecnico]. E-mail: ricardo@iprj.uerj.br

2003-07-01

In this paper we report advances about the three-dimensional nodal discrete-ordinates approximations of neutron transport equation for Cartesian geometry. We use the combined collocation method of the angular variables and nodal approach for the spatial variables. By nodal approach we mean the iterated transverse integration of the S{sub N} equations. This procedure leads to the set of one-dimensional averages angular fluxes in each spatial variable. The resulting system of equations is solved with the LTS{sub N} method, first applying the Laplace transform to the set of the nodal S{sub N} equations and then obtained the solution by symbolic computation. We include the LTS{sub N} method by diagonalization to solve the nodal neutron transport equation and then we outline the convergence of these nodal-LTS{sub N} approximations with the help of a norm associated to the quadrature formula used to approximate the integral term of the neutron transport equation. (author)

Solving the uncommon reactor core neutronics problems

International Nuclear Information System (INIS)

Vondy, D.R.; Fowler, T.B.

1980-01-01

The common reactor core neutronics problems have fundamental neutron space, energy spectrum solutions. Typically the most positive eigenvalue is associated with an all-positive flux for the pseudo-steady-state condition (k/sub eff/), or the critical state is to be effected by selective adjustment of some variable such as the fuel concentration. With sophistication in reactor analysis has come the demand for solutions of other, uncommon neutronics problems. Importance functionss are needed for sensitivity and uncertainty analyses, as for ratios of intergral reaction rates such as the fuel conversion (breeding) ratio. The dominant higher harmonic solution is needed in stability analysis. Typically the desired neutronics solution must contain negative values to qualify as a higher harmonic or to satisfy a fixed source containing negative values. Both regular and adjoint solutions are of interest as are special integrals of the solutions to support analysis

Cardiological aspects of carbon monoxide poisoning.

Science.gov (United States)

Marchewka, Jakub; Gawlik, Iwona; Dębski, Grzegorz; Popiołek, Lech; Marchewka, Wojciech; Hydzik, Piotr

2017-01-01

The aim of this study was to assess cardiological manifestations of carbon monoxide (CO) poisoning. Background/introduction: Carbon monoxide intoxication is one of the most important toxicological causes of morbidity and mortality worldwide. Early clinical manifestation of CO poisoning is cardiotoxicity. We enrolled 75 patients (34 males and 41 females, mean age 37.6 ± 17.7 y/o) hospitalized due to CO poisoning. Laboratory tests including troponin I, blood pressure measurements, HR and electrocardiograms (ECG) were collected. Pach's scale scoring and grading system was used to establish severity of poisoning. Grade of poisoning is positively correlated with troponin I levels and systolic blood pressure. Moreover, troponin levels are significantly correlated with exposition time, lactates and are higher in tachycardiac, hypertensive and positive ECG subpopulations. COHb levels are indicative of exposure but do not correlate with grade of poisoning. The main cause of CO poisoning were bathroom heaters - 83%, only 11% of examined intoxicated population were equipped with CO detectors. Complex cardiological screening covering troponin levels, ECG, blood pressure and heart rate measurements as well as complete blood count with particular attention to platelet parameters should be performed in each case where CO intoxication is suspected. More emphasis on education on CO poisoning is needed.

Optimization of the indirect at neutron activation technique for the determination of boron in aqueous solutions

International Nuclear Information System (INIS)

Luz, L.C.Q.P. da.

1984-01-01

The purpose of this work was the development of an instrumental method for the optimization of the indirect neutron activation analysis of boron in aqueous solutions. The optimization took into account the analytical parameters under laboratory conditions: activation carried out with a 241 Am/Be neutron source and detection of the activity induced in vanadium with two NaI(Tl) gamma spectrometers. A calibration curve was thus obtained for a concentration range of 0 to 5000 ppm B. Later on, experimental models were built in order to study the feasibility of automation. The analysis of boron was finally performed, under the previously established conditions, with an automated system comprising the operations of transport, irradiation and counting. An improvement in the quality of the analysis was observed, with boron concentrations as low as 5 ppm being determined with a precision level better than 0.4%. The experimental model features all basic design elements for an automated device for the analysis of boron in agueous solutions wherever this is required, as in the operation of nuclear reactors. (Author) [pt

Plant Poisoning among Children in Rural Sri Lanka

Directory of Open Access Journals (Sweden)

M. B. Kavinda Chandimal Dayasiri

2017-01-01

Full Text Available Plant poisoning is a common presentation in paediatric practice and an important cause of preventable mortality and morbidity in Sri Lanka. The burden of plant poisoning is largely underexplored. The current multicenter study based in rural Sri Lanka assessed clinical profiles, poison related factors, clinical management, complications, outcomes, and risk factors associated with plant poisoning in the paediatric age group. Among 325 children, 57% were male with 64% being below five years of age. 99.4% had ingested the poison. Transfer rate was 66.4%. Most had unintentional poisoning. Commonest poison plant was Jatropha circus and poisoning event happened mostly in home garden. 29% of parents practiced harmful first-aid practices. 32% of children had delayed presentations to which the commonest reason was lack of parental concern regarding urgency of seeking medical care. Presence of poisonous plants in home garden was the strongest risk factor for plant poisoning. Mortality rate was 1.2% and all cases had Oleander poisoning. The study revealed the value of community awareness regarding risk factors and awareness among healthcare workers regarding the mostly benign nature of plant poisoning in children in view of limiting incidence of plant poisoning and reducing expenditure on patient management.

Slow arsenic poisoning of the contaminated groundwater users

International Nuclear Information System (INIS)

Uddin, M. M.; Harun-Ar-Rashid, A. K. M.; Hossain, S. M.; Hafiz, M. A.; Nahar, K.; Mubin, S. H.

2006-01-01

This paper gives impact of Arsenic contaminated water on human health as well as overview of the extent and severity of groundwater arsenic contamination in Bangladesh. Scalp hair is the most important part of the human body to monitor the accumulation of this type of poison. Therefore, an experiment has been carried out by Neutron Activation Analysis at Atomic Energy Research Establishment , Savar, Dhaka, Bangladesh on human hair of corresponding tube well water users of these areas to determine the total accumulation of arsenic to their body. Hair samples collected from the region where the groundwater was found highly contaminated with arsenic. The obtained results of arsenic concentration in the lower age (Hb) categories of users (below 12 years of age users) is in the range of 0.33 to 3.29 μg/g (ppm) and that in the Hu categories (upper 12 years of age users) is 0.47 to 6.64 μg/g (ppm). Where as maximum permissible range is 1 ppm certified from WHO. Results show that the peoples are highly affected where the groundwater is highly contaminated with arsenic and acts as the primary source of arsenic poisoning among the peoples of those areas. The results indicate that human population is affected with arsenic locally using the contaminated water for a long time

Carbon Monoxide Poisoning

Directory of Open Access Journals (Sweden)

Alisa Wray

2016-07-01

Full Text Available Audience: This oral boards case is appropriate for all emergency medicine learners (residents, interns, and medical students. Introduction: Carbon monoxide (CO is a colorless and odorless gas that typically results from combustion. It binds hemoglobin, dissociating oxygen, causing headache, weakness, confusion and possible seizure or coma. Pulse oxygen levels may be falsely elevated. Practitioners should maintain a high index of suspicion for carbon monoxide poisoning. If caught early CO poisoning is reversible with oxygen or hyperbaric oxygen therapy. Objectives: The learner will assess a patient with altered mental status and weakness, ultimately identifying that the patient has carbon monoxide poisoning. The learner will treat the patient with oxygen and admit/transfer the patient for hyperbaric oxygenation. Method: Oral boards case

Response of solute and precipitation-strengthened copper alloys at high neutron exposure

International Nuclear Information System (INIS)

Garner, F.A.; Hamilton, M.L.; Shikama, T.; Edwards, D.J.; Newkirk, J.W.

1991-11-01

A variety of solute and precipitation strengthened copper base alloys have been irradiated to neutron-induced displacement levels of 34 to 150 dpa at 415 degrees C and 32 dpa at 529 degrees C in the Fast Flux Test Facility to assess their potential for high heat flux applications in fusion reactors. Several MZC-type alloys appear to offer the most promise for further study. For low fluence applications CuBeNi and spinodally strengthened CuNiTi alloys may also be suitable. Although Cu-2Be resists swelling, it is not recommended for fusion reactor applications because of its low conductivity

Response of solute and precipitation-strengthened copper alloys at high neutron exposure

Energy Technology Data Exchange (ETDEWEB)

Garner, F.A.; Hamilton, M.L. [Pacific Northwest Lab., Richland, WA (United States); Shikama, T. [Tohoku Univ., Oarai Branch (Japan); Edwards, D.J.; Newkirk, J.W. [Missouri Univ., Rolla, MO (United States)

1991-11-01

A variety of solute and precipitation strengthened copper base alloys have been irradiated to neutron-induced displacement levels of 34 to 150 dpa at 415{degrees}C and 32 dpa at 529{degrees}C in the Fast Flux Test Facility to assess their potential for high heat flux applications in fusion reactors. Several MZC-type alloys appear to offer the most promise for further study. For low fluence applications CuBeNi and spinodally strengthened CuNiTi alloys may also be suitable. Although Cu-2Be resists swelling, it is not recommended for fusion reactor applications because of its low conductivity.

The numerical analysis of eigenvalue problem solutions in multigroup neutron diffusion theory

International Nuclear Information System (INIS)

Woznicki, Z.I.

1995-01-01

The main goal of this paper is to present a general iteration strategy for solving the discrete form of multidimensional neutron diffusion equations equivalent mathematically to an eigenvalue problem. Usually a solution method is based on different levels of iterations. The presented matrix formalism allows us to visualize explicitly how the used matrix splitting influences the matrix structure in an eigenvalue problem to be solved as well as the interdependence between inner and outer iterations within global iterations. Particular iterative strategies are illustrated by numerical results obtained for several reactor problems. (author). 21 refs, 35 figs, 16 tabs

Fission product poisoning in KS-150 reactor operation

International Nuclear Information System (INIS)

Rana, S.B.

1978-01-01

A three-dimensional model of the KS-150 reactor was used to study reactivity changes induced by reactor poisoning with fission products Xe 135 and Sm 149 . A comparison of transients caused by the poisoning showed the following differences: (1) the duration of the transient Xe poisoning (2 days) is shorter by one order of magnitude than the duration of Sm poisoning (20 days); however, the level of Xe poisoning is greater approximately by one order than the level of the Sm poisoning; (2) the level of steady-state Xe poisoning depends on the output level of the reactor; steady-state Sm poisoning does not depend on this level; (3) following reactor shutdown Xe poisoning may increase to the maximum value of up to Δrhosub(Xe)=20% and will then gradually decrease; Sm poisoning may reach maximum values of up to Δrhosub(Sm)=2% and does not decrease. (J.B.)

Arsenical poisoning of racehorses

Energy Technology Data Exchange (ETDEWEB)

Sutherland, G.N.; Fawell, E.V.; Brown, J.K.

1964-03-07

A case of arsenic poisoning in a training stable of Thoroughbred racehorses is described. This was due to the accidental spilling of an arsenical rat poison into the corn bin. Nine horses were affected. The mortality rate was 100 per cent. 1 table.

Potassium permanganate poisoning--a rare cause of fatal self poisoning.

OpenAIRE

Ong, K L; Tan, T H; Cheung, W L

1997-01-01

Attempted suicide by self poisoning is common because of the ready availability of drugs, whether prescribed or bought over the counter. In some cases, the ingestion of seemingly innocuous household products or chemicals can result in death. Potassium permanganate is an example. Poisoning with potassium permanganate can be fatal when a significant amount is ingested, as shown by a patient who suffered both the corrosive and systemic toxic effects of this chemical.

Cartap Hydrochloride Poisoning.

Science.gov (United States)

Kalyaniwala, Kimmin; Abhilash, Kpp; Victor, Peter John

2016-08-01

Cartap hydrochloride is a moderately hazardous nereistoxin insecticide that is increasingly used for deliberate self-harm in India. It can cause neuromuscular weakness resulting in respiratory failure. We report a patient with 4% Cartap hydrochloride poisoning who required mechanical ventilation for 36-hours. He recovered without any neurological deficits. We also review literature on Cartap hydrochloride poisoning. © Journal of the Association of Physicians of India 2011.

American Association of Poison Control Centers

Science.gov (United States)

... add poison control as a contact in your smartphone. Take the pledge! National Poison Prevention Week is March 19-25! Be a part of the conversation by following #PreventPoison and #NPPW2017 on social media, and check out AAPCC's NPPW webpage and press ...

Beginning-of-life neutronic analysis of a 3000-MW(t) HTGR

International Nuclear Information System (INIS)

Vigil, J.C.

1975-12-01

The results of a study of safety-related neutronic characteristics for the beginning-of-life core of a 3000-MW(t) High-Temperature Gas-Cooled Reactor are presented. Emphasis was placed on the temperature-dependent reactivity effects of fuel, moderator, control poisons, and fission products. Other neutronic characteristics studied were gross and local power distributions, neutron kinetics parameters, control rod and other material worths and worth distributions, and the reactivity worth of a selected hypothetical perturbation in the core configuration. The study was performed for the most part using discrete-ordinates transport theory codes and neutron cross sections that were interpolated from a four-parameter nine-group library supplied by the HTGR vendor. A few comparison calculations were also performed using nine-group data generated with an independent cross-section processing code system. Results from the study generally agree well with results reported by the HTGR vendor

49 CFR 172.540 - POISON GAS placard.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false POISON GAS placard. 172.540 Section 172.540... SECURITY PLANS Placarding § 172.540 POISON GAS placard. (a) Except for size and color, the POISON GAS... the POISON GAS placard and the symbol must be white. The background of the upper diamond must be black...

Multi-element neutron activation analysis and solution of classification problems using multidimensional statistics

International Nuclear Information System (INIS)

Vaganov, P.A.; Kol'tsov, A.A.; Kulikov, V.D.; Mejer, V.A.

1983-01-01

The multi-element instrumental neutron activation analysis of samples of mountain rocks (sandstones, aleurolites and shales of one of gold deposits) is performed. The spectra of irradiated samples are measured by Ge(Li) detector of the volume of 35 mm 3 . The content of 22 chemical elements is determined in each sample. The results of analysis serve as reliable basis for multi-dimensional statistic information processing, they constitute the basis for the generalized characteristics of rocks which brings about the solution of classification problem for rocks of different deposits

Common causes of poisoning: etiology, diagnosis and treatment.

Science.gov (United States)

Müller, Dieter; Desel, Herbert

2013-10-01

In 2011, German hospitals treated approximately 205 000 patients suffering from acute poisoning. Change is seen over time both in the types of poisoning that occur and in the indications for specific treatment. This article is based on a selective review of the literature, with special attention to the health reports of the German federal government, the annual reports of the GIZ-Nord Poisons Center (the poison information center for the four northwestern states of Germany, i.e. Bremen, Hamburg, Lower Saxony and Schleswig-Holstein), and the recommendations of international medical associations. From 1996 to 2011, the GIZ-Nord Poisons Center answered more than 450 000 inquiries, most of which involved exposures to medical drugs, chemicals, plants, foods, or cosmetics. Poisoning was clinically manifest in only a fraction of these cases. Ethanol intoxication is the commonest type of acute poisoning and suicide by medical drug overdose is the commonest type of suicide by poisoning. Death from acute poisoning is most commonly the result of either smoke inhalation or illegal drug use. Severe poisoning is only rarely due to the ingestion of chemicals (particularly detergents and cleaning products), cosmetics, or plant matter. Medical procedures that are intended to reduce the absorption of a poison or enhance its elimination are now only rarely indicated. Antidotes (e.g., atropine, 4-dimethylaminophenol, naloxone, toluidine blue) are available for only a few kinds of poisoning. Randomized clinical trials of treatment have been carried out for only a few substances. Most exposures to poisons can be treated with general emergency care and, if necessary, with symptomatic intensive-care measures. Poison information centers help ensure that cases of poisoning are dealt with efficiently. The data they collect are a useful aid to toxicological assessment and can serve as a point of departure for research projects.

49 CFR 172.416 - POISON GAS label.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false POISON GAS label. 172.416 Section 172.416... SECURITY PLANS Labeling § 172.416 POISON GAS label. (a) Except for size and color, the POISON GAS label... POISON GAS label and the symbol must be white. The background of the upper diamond must be black and the...

Modified poisoning severity score for early prognostic evaluation in acute paraquat poisoning

Directory of Open Access Journals (Sweden)

Feng-lin SONG

2018-04-01

Full Text Available Objective To study the applied value of modified poisoning severity score (PSS for early prognostic evaluation in acute paraquat poisoning. Methods Thirty-seven patients with acute paraquat poisoning from June 2013 to June 2016 were enrolled. The PSS score, the modified PSS score, the acute physiology and the chronic health status Ⅱ score (APACHE Ⅱ of the patients were calculated. The relationship between modified PSS and APACHE Ⅱ was analyzed. Also the factors that affect outcome were analyzed by logistic regression analysis. The work characteristic curve (ROC curve of the PSS, the modified PSS and the APECH Ⅱ were drawn and compared. Results There was a positive correlation between the risk of death and admission time, poisonous dose, the concentration of urine paraquat, and white blood cell count (P<0.05. There was a significant correlation between the modified PSS and the APACHE Ⅱ(P<0.0001. The immediate PSS score, the modified PSS score, and the APACHE Ⅱ score were significant for the prognosis of patients with acute paraquat poisoning. The area under the curve (AUC was in turn 0.774, 0.788, 0.799. Among them, the best bound of the modified PSS score was 6.5 (when the score is greater than 6.5, the risk of death is higher. Further comparison of the area under the three curves showed that there was no significant difference in the area under the ROC curve between the three scores in predicting the prognosis of death [P=0.7633(PSS-DPSS, P=0.7791(PSS-APACHE Ⅱ, P=0.8918(DPSS-APACHE Ⅱ]. Conclusion Modified PSS is helpful in early predicting the prognosis of acute paraquat poisoning. DOI: 10.11855/j.issn.0577-7402.2018.04.13

Chelation Therapy for Mercury Poisoning

OpenAIRE

Rong Guan; Han Dai

2009-01-01

Chelation therapy has been the major treatment for heavy metal poisoning. Various chelating agents have been developed and tested for treatment of heavy metal intoxications, including mercury poisoning. It has been clearly shown that chelating agents could rescue the toxicity caused by heavy metal intoxication, but the potential preventive role of chelating agents against heavy metal poisoning has not been explored much. Recent paper by Siddiqi and colleagues has suggested a protective role o...

National Poison Prevention Week Promotional Materials.

Science.gov (United States)

Poison Prevention Week Council, Washington, DC.

This collection of materials for parents, early childhood workers, the elderly, and anyone in situations requiring safeguards against poisoning, spans the years 1993 and 1994 and is intended to promote National Poison Prevention Week. The materials included are: (1) the 31-page, illustrated report on National Poison Prevention Week for 1993,…

Paraquat poisoning in the dog

International Nuclear Information System (INIS)

O'Sullivan, S.P.

1989-01-01

Recovery from paraquat poisoning in the dog is rare. This is a report of a case of recovery from confirmed paraquat poisoning in a clinical setting. The dog exhibited the usual signs of paraquat poisoning. The diagnosis was confirmed on toxicological analysis of urine using an ion exchange technique. The dog was treated with frusemide, nicotinamide, corticosteroids, α-tocopherol, vitamin A, etamiphylline camsylate and ampicillin. He recovered after seven weeks of intensive therapy. Alternative treatments are discussed

Dynamic proton polarisation on polymers in solution: creating contrast in neutron scattering

International Nuclear Information System (INIS)

Grinten, M.G.D. van der

1995-01-01

Dynamic nuclear polarisation (DNP) as an alternative or additional method to create contrast in neutron small angle scattering has been investigated with emphasis on the study of polymers in solution. The need for high polarisations imposes specific requirements on the sample and its environment. Vitreous beads have been used as samples. Nuclear relaxation times show that they contain dissolved air. Parasitic scattering from the solvent is observed, probably arising from nanometer air bubbles. DNP is shown to be useful, in particular for samples that consist of mixtures of hydrogen-free and hydrogen-rich molecules, where the different molecules can be highlighted by changing the polarisation. ((orig.))

Levothyroxine Poisoning - Symptoms and Clinical Outcome

DEFF Research Database (Denmark)

Nygaard, Birgitte; Saedder, Eva A; Dalhoff, Kim

2015-01-01

Levothyroxine (LT), T4, poisoning is rarely associated with a severe outcome. However, cases with significant complications have been reported. The aim of this study was to identify factors associated with symptoms of poisoning including late-onset symptoms. All enquiries to the Danish Poison...... Information Centre (DPIC) concerning LT poisoning between March 2007 and September 2012 were reviewed and the following parameters were recorded: age, dose, time from ingestion, multiple drug intake and symptoms. To evaluate the frequency of late-onset symptoms, a subgroup of patients without initial symptoms...... patients, neither in children nor in adults (age 16-92 years) (p poisoning at the time of enquiry; however, in 9 of 21 (43%) patients, we were able to contact, late-onset symptoms existed. In none of the cases...

Approximate solution to neutron transport equation with linear anisotropic scattering

International Nuclear Information System (INIS)

Coppa, G.; Ravetto, P.; Sumini, M.

1983-01-01

A method to obtain an approximate solution to the transport equation, when both sources and collisions show a linearly anisotropic behavior, is outlined and the possible implications for numerical calculations in applied neutronics as well as shielding evaluations are investigated. The form of the differential system of equations taken by the method is quite handy and looks simpler and more manageable than any other today available technique. To go deeper into the efficiency of the method, some typical calculations concerning critical dimension of multiplying systems are then performed and the results are compared with the ones coming from the classical Ssub(N) approximations. The outcome of such calculations leads us to think of interesting developments of the method which could be quite useful in alternative to other today widespread approximate procedures, for any geometry, but especially for curved ones. (author)

Fissile materials in solution concentration measured by active neutron interrogation; Mesure de concentration en matiere fissile dans les liquides par interrogation neutronique active

Energy Technology Data Exchange (ETDEWEB)

Romeyer Dherbey, J.; Passard, Ch.; Cloue, J.; Bignan, G.

1993-12-31

The use of the active neutron interrogation to measure the concentration of plutonium contained in flow solutions is particularly interesting for fuel reprocessing plants. Indeed, this method gives a signal which is in a direct relation with the fissile materials concentration. Moreover, it is less sensitive to the gamma dose rate than the other nondestructive methods. Two measure methods have been evolved in CEA. Their principles are given into details in this work. The first one consists to detect fission delayed neutrons induced by a {sup 252} Cf source. In the second one fission prompt neutrons induced by a neutron generator of 14 MeV are detected. (O.M.). 6 refs.

Characteristics of poisoning cases in Adiyaman city

Directory of Open Access Journals (Sweden)

Öznur Uludağ

2015-09-01

Full Text Available Objective: Aim of this study was to retrospectively evaluate poisoning cases in an intensive care unit (ICU in order to determine the profile of poisoning cases, update epidemiological data in Adiyaman, and contribute to data about poisoning in our country. Methods: Between 01-01-2012 and 31-12-2013 174 patients (116 males, 58 females with a mean age of 23.7 years were treated. Demographic characteristics, reasons and ways of poisoning, types of toxic substances, length of their ICU stay and prognosis were evaluated. Results: 2733 patients admitted to the intensive care unit were 174 poisoning cases. Poisoning ways were suicide by drug overdose (n=162, 93.1%, and accidental poisoning (n=12,6.9%.119 patients (66.5% had single drug intake, thirty-three patients (18.4% with multiple drug intake, and 16 (8.9% were poisoned by organic phosphates. The most common drug used for suicide was antidepressants (n=87.5%. 32 patients (18.4% took analgesics and anti-inflammatory drugs. A total of 152 patients taking the drug, 22 patients were poisoned by other means. The median length of patient stay was 2 days (range 1-20 days. Ninety-nine patients (56.9% recovered and were discharged.72 patients (41.4% were admitted to inpatient after intensive care unit. Patients were followed up by asking poisoning suicidal psychiatric consultation.1 patient was followed up for 20 days in intensive care due to alcohol poisoning but was died.2 patients (1.1% were referred to a center forward. Conclusion: Majority of the patients were females, who took drugs with suicidal intention. Frequent use of antidepressants, which are not subject to control by authorities, to commit suicide was remarkable.

Chronic arsenic poisoning following ayurvedic medication.

Science.gov (United States)

Pinto, Benzeeta; Goyal, Palvi; Flora, S J S; Gill, K D; Singh, Surjit

2014-12-01

Ayurveda, Indian traditional system of medicine, is practiced commonly in South East Asia and in many parts of the world. Many ayurvedic drugs contain heavy metals and may lead to metal toxicity. Of these, chronic lead poisoning is the most common. Chronic arsenic poisoning following the use of ayurvedic medication, though reported, is rare. We describe three patients who presented with features of chronic arsenic poisoning following prolonged ayurvedic medication use. The diagnosis of chronic arsenic poisoning was confirmed by high arsenic levels in the blood, urine, hair, and nails in all the three patients and in ayurvedic drug in two patients. The ayurvedic medication was discontinued and treatment with D-penicillamine started. At 6 months after treatment, blood arsenic levels returned to normal with clinical recovery in all of them. Arsenic poisoning following ayurvedic medication is much less common than lead poisoning, though mineral ayurvedic medicines may lead to it. We used D-penicillamine as chelator and all of them recovered. Whether withdrawal of medication alone or D-penicillamine also played a role in recovery is unclear and needs to be assessed.

Pulmonary edema in acute carbon monoxide poisoning

International Nuclear Information System (INIS)

Kim, Kun Sang; Chang, Kee Hyun; Lee, Myung Uk

1974-01-01

Acute carbon monoxide poisoning has frequently occurred in Korean, because of the coal briquette being widely used as fuel in Korean residences. Carbon monoxide poisoning has been extensively studied, but it has been sparsely reported that pulmonary edema may develop in acute CO poisoning. We have noticed nine cases of pulmonary edema in acute CO poisoning last year. Other possible causes of pulmonary edema could be exclude in all cases but one. The purpose of this paper is to describe nine cases of pulmonary edema complicated in acute CO poisoning and discuss the pathogenesis and the prognosis

Article Commentary: Chelation Therapy for Mercury Poisoning

Directory of Open Access Journals (Sweden)

Rong Guan

2009-01-01

Full Text Available Chelation therapy has been the major treatment for heavy metal poisoning. Various chelating agents have been developed and tested for treatment of heavy metal intoxications, including mercury poisoning. It has been clearly shown that chelating agents could rescue the toxicity caused by heavy metal intoxication, but the potential preventive role of chelating agents against heavy metal poisoning has not been explored much. Recent paper by Siddiqi and colleagues has suggested a protective role of chelating agents against mercury poisoning, which provides a promising research direction for broader application of chelation therapy in prevention and treatment of mercury poisoning.

Pulmonary edema in acute carbon monoxide poisoning

Energy Technology Data Exchange (ETDEWEB)

Kim, Kun Sang; Chang, Kee Hyun; Lee, Myung Uk [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1974-10-15

Acute carbon monoxide poisoning has frequently occurred in Korean, because of the coal briquette being widely used as fuel in Korean residences. Carbon monoxide poisoning has been extensively studied, but it has been sparsely reported that pulmonary edema may develop in acute CO poisoning. We have noticed nine cases of pulmonary edema in acute CO poisoning last year. Other possible causes of pulmonary edema could be exclude in all cases but one. The purpose of this paper is to describe nine cases of pulmonary edema complicated in acute CO poisoning and discuss the pathogenesis and the prognosis.

[A relational database to store Poison Centers calls].

Science.gov (United States)

Barelli, Alessandro; Biondi, Immacolata; Tafani, Chiara; Pellegrini, Aristide; Soave, Maurizio; Gaspari, Rita; Annetta, Maria Giuseppina

2006-01-01

Italian Poison Centers answer to approximately 100,000 calls per year. Potentially, this activity is a huge source of data for toxicovigilance and for syndromic surveillance. During the last decade, surveillance systems for early detection of outbreaks have drawn the attention of public health institutions due to the threat of terrorism and high-profile disease outbreaks. Poisoning surveillance needs the ongoing, systematic collection, analysis, interpretation, and dissemination of harmonised data about poisonings from all Poison Centers for use in public health action to reduce morbidity and mortality and to improve health. The entity-relationship model for a Poison Center relational database is extremely complex and not studied in detail. For this reason, not harmonised data collection happens among Italian Poison Centers. Entities are recognizable concepts, either concrete or abstract, such as patients and poisons, or events which have relevance to the database, such as calls. Connectivity and cardinality of relationships are complex as well. A one-to-many relationship exist between calls and patients: for one instance of entity calls, there are zero, one, or many instances of entity patients. At the same time, a one-to-many relationship exist between patients and poisons: for one instance of entity patients, there are zero, one, or many instances of entity poisons. This paper shows a relational model for a poison center database which allows the harmonised data collection of poison centers calls.

Outsmarting Poison Ivy and Other Poisonous Plants

Science.gov (United States)

... poison sumac. Protectants such as baking soda or colloidal oatmeal relieve minor irritation and itching. Aluminum acetate ... Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993 1-888-INFO-FDA (1- ...

16 CFR 1700.15 - Poison prevention packaging standards.

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Poison prevention packaging standards. 1700.15 Section 1700.15 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION POISON PREVENTION PACKAGING ACT OF 1970 REGULATIONS POISON PREVENTION PACKAGING § 1700.15 Poison prevention packaging...

Poison ivy - oak - sumac rash

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/000027.htm Poison ivy - oak - sumac rash To use the sharing features on this page, please enable JavaScript. Poison ivy, oak, and sumac are plants that commonly ...

Extracorporeal Treatment in Phenytoin Poisoning

DEFF Research Database (Denmark)

Anseeuw, Kurt; Mowry, James B; Burdmann, Emmanuel A

2016-01-01

The Extracorporeal Treatments in Poisoning (EXTRIP) Workgroup conducted a systematic literature review using a standardized process to develop evidence-based recommendations on the use of extracorporeal treatment (ECTR) in patients with phenytoin poisoning. The authors reviewed all articles......) despite its high protein binding and made the following recommendations. ECTR would be reasonable in select cases of severe phenytoin poisoning (neutral recommendation, 3D). ECTR is suggested if prolonged coma is present or expected (graded 2D) and it would be reasonable if prolonged incapacitating ataxia...... is present or expected (graded 3D). If ECTR is used, it should be discontinued when clinical improvement is apparent (graded 1D). The preferred ECTR modality in phenytoin poisoning is intermittent hemodialysis (graded 1D), but hemoperfusion is an acceptable alternative if hemodialysis is not available...

Acute selenium poisoning in cattle

Energy Technology Data Exchange (ETDEWEB)

Shortridge, E H; O' Hara, P J; Marshall, P M

1971-01-01

Three hundred and seventy-six (67%) of 557 calves of approximately 150-200 kg live-weight died following subcutaneous injection of a solution containing 100 mg selenium as sodium selenite. Eight per cent of the 254 heifer calves and 56% of the 303 steers died. The calves had endured the stress of being weaned twice and held in stockyards twice as well as encountering wet weather during the 4 days before receiving the selenium. The heifer calves were also vaccinated with Br. abortus strain 19 vaccine at the same time as receiving the selenium. The clinical signs and pathological findings of circulatory failure and myocardial damage were similar to those previously reported in acute selenium poisoning.

The influence of xenon poisoning in high-flux reactors on the choice of control rod speeds (1961); Influence de l'empoisonnement xenon dans les piles a haut flux sur le choix de la vitesse des barres de controle (1961)

Energy Technology Data Exchange (ETDEWEB)

Furet, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1961-07-01

- The general laws are restated concerning the changes in xenon and iodine concentrations in thermal neutron reactors, assuming an uniform neutron flux distribution in the core. It is shown how the evolution in the xenon poisoning influences the selection of the control rod speed, at start-up. Certain simple methods of calculation are developed making it possible to resolve the problem of the choice of this speed in the case where the xenon poisoning is taken into account. (author) [French] - On rappelle les lois generales relatives aux evolutions de concentration xenon et iode dans les piles atomiques a neutrons thermiques lorsqu'on suppose une repartition uniforme du flux de neutrons dans le coeur. On montre comment l'evolution de l'empoisonnement xenon influe sur le choix de la vitesse des barres de controle en periode de demarrage. On developpe certaines methodes de calculs simples permettant de resoudre le probleme du choix de la vitesse des barres de controle, dans le cas ou l'on tient compte de l'empoisonnement xenon. (auteur)

Is Your Child Safe from Lead Poisoning?

Centers for Disease Control (CDC) Podcasts

In this podcast, Dr. Mary Jean Brown, chief of CDC's Lead Poisoning and Prevention Program, discusses the importance of testing children for lead poisoning, who should be tested, and what parents can do to prevent lead poisoning.

Amnesic Shellfish Poisoning (ASP)

DEFF Research Database (Denmark)

Ravn, H.

HAB Publ. Ser. vol 1 is a supplement to Chapter 7 Mehtods for Domoic Acid, the Amnesic Shellfish Poisons in the IOC Manual of Harmful Marine Microalgae......HAB Publ. Ser. vol 1 is a supplement to Chapter 7 Mehtods for Domoic Acid, the Amnesic Shellfish Poisons in the IOC Manual of Harmful Marine Microalgae...

Methods of neutron spectrometry

International Nuclear Information System (INIS)

Doerschel, B.

1981-01-01

The different methods of neutron spectrometry are based on the direct measurement of neutron velocity or on the use of suitable energy-dependent interaction processes. In the latter case the measuring effect of a detector is connected with the searched neutron spectrum by an integral equation. The solution needs suitable unfolding procedures. The most important methods of neutron spectrometry are the time-of-flight method, the crystal spectrometry, the neutron spectrometry by use of elastic collisions with hydrogen nuclei, and neutron spectrometry with the aid of nuclear reactions, especially of the neutron-induced activation. The advantages and disadvantages of these methods are contrasted considering the resolution, the measurable energy range, the sensitivity, and the experimental and computational efforts. (author)

Some considerations on stochastic neutron populations (u)

International Nuclear Information System (INIS)

Souto, Francisco J.; Prinja, Anil K.

2010-01-01

The neutron population in a multiplying body containing a weak random source may depart considerably from its average or expected value. The resulting behavior of the system is then unpredictable and a fully stochastic description of the neutron population becomes necessary. Stochastic considerations are especially important when dealing with pulsed reactors or in the case of criticality excursions in the presence of a weak source. Using the theory of discrete-state continuous-time Markov processes, and subject to some physical approximations, Bell (I) obtained approximate solutions for the neutron number probability distributions (pdf), with and without an intrinsic rapdom neutron source, that were valid at late times and/ large neutron populations. In recent work (4), we obtained exact solutions for Bell's model problem, and in this paper we use these exact probability distributions to: (I) assess the accuracy of Bell's asymptotic solutions and show how the latter follow from the exact solutions, (2) rigorously examine the probability of obtaining a divergent chain reaction, and (3) demonstrate the existence of an abrupt transition from a stochastic to a deterministic phase with increasing source strength.

Reactor scram device using fluid poison tubes

International Nuclear Information System (INIS)

Iwasaki, Toshio; Hasegawa, Koji.

1979-01-01

Purpose: To improve the response function in the reactor scram with no wide space by injecting poisons in soluble poison guide tubes to such a liquid level as giving no effect on usual reactor operation. Constitution: Soluble poison guide tubes in a reactor are connected at their upper ends to a buffer tank and at their lower ends to a pressurizer by way of a header and an injection valve. The header is connected by way of a valve with a level meter, one end of which is connected to the buffer tank. During reactor operation, the injection valve is closed and the soluble poisons in the pressurizer vessel is maintained at a pressurized state and, while on the other hand, soluble poisons are injected by way of the header to the lower end of the soluble poison guide tubes by the opening of a valve, which is thereafter closed. Upon scram, a valve is closed to protect the level meter and pressurized poisons are rapidly filled in the guide tubes by the release of the injection valve. (Kawakami, Y.)

Carbon monoxide poisoning at motels, hotels, and resorts.

Science.gov (United States)

Weaver, Lindell K; Deru, Kayla

2007-07-01

Each year, more than 200 people in the United States die from carbon monoxide (CO) poisoning. Poisoning has occurred at motels, hotels, and resorts. Congressional mandate requires smoke alarms in all guest rooms; however, smoke alarms do not detect CO. Data on patients poisoned at hotels, motels, and resorts were evaluated at a hyperbaric medicine service. In 2005, legal databases and online news databanks were searched to discover additional incidents. Only victims evaluated in hospitals or declared dead at the scene were included. Cases of intentional poisoning and poisoning from fires were excluded. Between 1989 and 2004, 68 incidents of CO poisoning occurring at hotels, motels, and resorts were identified, resulting in 772 accidentally poisoned: 711 guests, 41 employees or owners, and 20 rescue personnel. Of those poisoned, 27 died, 66 had confirmed sequelae, and 6 had sequelae resulting in a jury verdict. Lodging-operated, faulty room heating caused 45 incidents, pool/spa boilers 16, CO entrained from outdoors 5, and unreported sources caused 2 incidents. Public verdicts have averaged $4.8 million per incident (range, $1 million to $17.5 million). Poisoning occurred at hotels of all classes. Despite these incidents, most properties did not install CO alarms, and requirements for CO alarms at hotels, motels, and resorts are rare. Guests of motels, hotels, and resorts remain at risk for injury or death from CO poisoning. Measures to prevent CO poisoning of guests and employees of the lodging industry should be evaluated.

The numerical analysis of eigenvalue problem solutions in the multigroup neutron diffusion theory

International Nuclear Information System (INIS)

Woznicki, Z.I.

1994-01-01

The main goal of this paper is to present a general iteration strategy for solving the discrete form of multidimensional neutron diffusion equations equivalent mathematically to an eigenvalue problem. Usually a solution method is based on different levels of iterations. The presented matrix formalism allows us to visualize explicitly how the used matrix splitting influences the matrix structure in an eigenvalue problem to be solved as well as the interdependence between inner and outer iteration within global iterations. Particular interactive strategies are illustrated by numerical results obtained for several reactor problems. (author). 21 refs, 32 figs, 15 tabs

The numerical analysis of eigenvalue problem solutions in the multigroup neutron diffusion theory

Energy Technology Data Exchange (ETDEWEB)

Woznicki, Z I [Institute of Atomic Energy, Otwock-Swierk (Poland)

1994-12-31

The main goal of this paper is to present a general iteration strategy for solving the discrete form of multidimensional neutron diffusion equations equivalent mathematically to an eigenvalue problem. Usually a solution method is based on different levels of iterations. The presented matrix formalism allows us to visualize explicitly how the used matrix splitting influences the matrix structure in an eigenvalue problem to be solved as well as the interdependence between inner and outer iteration within global iterations. Particular interactive strategies are illustrated by numerical results obtained for several reactor problems. (author). 21 refs, 32 figs, 15 tabs.

System of adjoint P1 equations for neutron moderation; Sistema de equacoes P1 adjuntas para a moderacao de neutrons

Energy Technology Data Exchange (ETDEWEB)

Martinez, Aquilino Senra; Silva, Fernando Carvalho da; Cardoso, Carlos Eduardo Santos [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear

2000-07-01

In some applications of perturbation theory, it is necessary know the adjoint neutron flux, which is obtained by the solution of adjoint neutron diffusion equation. However, the multigroup constants used for this are weighted in only the direct neutron flux, from the solution of direct P1 equations. In this work, this procedure is questioned and the adjoint P1 equations are derived by the neutron transport equation, the reversion operators rules and analogies between direct and adjoint parameters. (author)

Poison control center - emergency number

Science.gov (United States)

For a POISON EMERGENCY call: 1-800-222-1222 ANYWHERE IN THE UNITED STATES This national hotline number will let you ... is a free and confidential service. All local poison control centers in the United States use this ...

Benzodiazepine poisoning in elderly.

Science.gov (United States)

Vukcević, Natasa Perković; Ercegović, Gordana Vuković; Segrt, Zoran; Djordjević, Snezana; Stosić, Jasmina Jović

2016-03-01

Benzodiazepines are among the most frequently ingested drugs in self-poisonings. Elderly may be at greater risk compared with younger individuals due to impaired metabolism and increased sensitivity to benzodiazepines. The aim of this study was to assess toxicity of benzodiazepines in elderly attempted suicide. A retrospective study of consecutive presentations to hospital after self-poisoning with benzodiazepines was done. Collected data consisted of patient's characteristics (age, gender), benzodiazepine ingested with its blood concentrations at admission, clinical findings including vital signs and Glasgow coma score, routine blood chemistry, complications of poisoning, details of management, length of hospital stay and outcome. According the age, patients are classified as young (15-40-year old), middle aged (41-65-year old) and elderly (older than 65). During a 2-year observational period 387 patients were admitted because of pure benzodiazepine poisoning. The most frequently ingested drug was bromazepam, the second was diazepam. The incidence of coma was significantly higher, and the length of hospital stay significantly longer in elderly. Respiratory failure and aspiration pneumonia occurred more frequently in old age. Also, flumazenil was more frequently required in the group of elderly patients. Massive benzodiazepines overdose in elderly may be associated with a significant morbidity, including deep coma with aspiration pneumonia, respiratory failure, and even death. Flumazenil is indicated more often to reduce CNS depression and prevent complications of prolonged unconsciousness, but supportive treatment and proper airway management of comatose patients is the mainstay of the treatment of acute benzodiazepine poisoning.

Analytical representation for solution of the neutron point kinetics equation with time-dependent reactivity and free of the stiffness character

International Nuclear Information System (INIS)

Silva, Milena Wollmann da

2013-01-01

In this work, we report a genuine analytical representation for the solution of the neutron point kinetics equation free of the stiffness character, assuming that the reactivity is a continuous and sectionally continuous function of time. To this end, we initially cast the point kinetics equation in a first order linear differential equation. Next, we split the corresponding matrix as a sum of a diagonal matrix with a matrix, whose components contain the off-diagonal elements. Next, expanding the neutron density and the delayed neutron precursors concentrations in a truncated series, and replacing these expansions in the matrix equation, we come out with an equation, which allows to construct a recursive system, a first order matrix differential equation with source. The fundamental characteristic of this system relies on the fact that the corresponding matrix is diagonal, meanwhile the source term is written in terms of the matrix with the off-diagonal components. Further, the first equation of the recursive system has no source and satisfies the initial conditions. On the other hand, the remaining equations satisfy the null initial condition. Due to the diagonal feature of the matrix, we attain analytical solutions for these recursive equations. We also mention that we evaluate the results for any time value, without the analytical continuity because the purposed solution is free on the stiffness character. Finally, we present numerical simulations and comparisons against literature results, considering specific the applications for the following reactivity functions: constant, step, ramp, and sine. (author)

Poisoning of animals by industrial fumes

Energy Technology Data Exchange (ETDEWEB)

Hofmann, P

1937-01-01

Autopsy findings of game that died presumably due to poisoning by arsenic are presented. Corrosive gastroenteritis with edema and ecchymosis of the mucosa, and partly ulceration of the stomach, and fatty degeneration of the kidneys and liver were found in hares and stags. Arsenic was detected in the gastric content, liver, and other organs. These cases were diagnosed as acute to subacute poisoning by arsenic. Catarrhal gastrointestinal mucosa, pseudomembranes, in the esophagus, inflammatory edema of the nasal septum and laryngeai mucosa, and sometimes liver cirrhosis and edema of the spleen were found in red deer, roes, and hares. In these cases, poisoning by arsenic could not be identified as the primary cause of death. The symptoms of the poisoning were similar to cause of death. The symptoms of the poisoning were similar to those observed in game around a smelter prior to the installation of an efficient arsenic trap.

Determination of boron in aqueous solutions by solid state nuclear track detectors technique, using a filtered neutron beam

International Nuclear Information System (INIS)

Moraes, M.A.P.V. de; Pugliesi, R.; Khouri, M.T.F.C.

1985-11-01

The solid state nuclear track detectors technique has been used for determination of boron in aqueous solutions, using a filtered neutron beam. The particles tracks from the 10 B(n,α)Li 7 reaction were registered in the CR-39 film, chemically etched in a (30%) KOH solution 70 0 C during 90 minutes. The obtained results showed the usefulness of this technique for boron determination in the ppm range. The inferior detectable limit was 9 ppm. The combined track registration efficiency factor K has been evaluated in the solutions, for the CR-39 detector and its values is K= (4,60 - + 0,06). 10 -4 cm. (Author) [pt

Experimental lead poisoning in chickens

Energy Technology Data Exchange (ETDEWEB)

Silven, L.

1967-01-01

Poisoning of water fowl due to the intake of lead shot is not rare in the USA. In order to study this kind of poisoning more closely domestic fowl were given varying amounts of lead shot and lead powder. This treatment did not provoke any symptoms of poisoning. Chemical analyses of different organs, muscles, skeleton and eggs yielded low lead values. It is concluded that the low toxicity of lead administered as lead shot to the domestic fowl is due to a low absorption rate from the gastro-intestinal tract.

Vital Signs-Alcohol Poisoning Deaths

Centers for Disease Control (CDC) Podcasts

This podcast is based on the January 2015 CDC Vital Signs report. In the United States, an average of six people die every day from alcohol poisoning. Learn what you can do to prevent binge drinking and alcohol poisoning.

Fabrication of thin cadmium cylinder coated with aluminum for neutron irradiation capsules

International Nuclear Information System (INIS)

Takeyama, Tomonori; Chiba, Masaaki

2001-03-01

In order to fabricate the irradiation capsule screened thermal neutron, a thin cadmium cylinder coated with aluminum was developed. The capsule is used for the fast neutron irradiation test. Requested specification of the cylinder are the thickness of 5.5 mm, the inner diameter of 23 mm, the length of 750 mm and the coated thickness of aluminum of 0.75 mm. Moreover, cadmium and aluminum adhere to each other. The cylinder was developed and fabricated by means of casting. The a new vacuum chamber in which solving and casting work is possible was fabricated to prevent cadmium oxidation and work safely from poison of cadmium. (author)

Unearthing poison use and consequent anecdotal vulture mortalities ...

African Journals Online (AJOL)

Aldicarb or carbofuran were the most commonly used poisons, but strychnine is still used by about one farmer out of 10. Poison is typically used by means of distributing poisoned baits in the landscape. Furthermore, willingness to use poison in the future was highest for farmers who own large properties with high livestock ...

Study on the treatment of acute thallium poisoning.

Science.gov (United States)

Zhang, Hong-Tao; Qiao, Bao-Ping; Liu, Bao-Ping; Zhao, Xian-Guo

2014-05-01

Acute thallium poisoning rarely occurs but is a serious and even fatal medical condition. Currently, patients with acute thallium poisoning are usually treated with Prussian blue and blood purification therapy. However, there are few studies about these treatments for acute thallium poisoning. Nine patients with acute thallium poisoning from 1 family were treated successfully with Prussian blue and different types of blood purification therapies and analyzed. Prussian blue combined with sequential hemodialysis, hemoperfusion and/or continuous veno-venous hemofiltration were effective for the treatment of patients with acute thallium poisoning, even after delayed diagnosis. Blood purification therapies help in the clearance of thallium in those with acute thallium poisoning. Prussian blue treatment may do the benefit during this process.

Structure of polyacrylic acid and polymethacrylic acid solutions: a small angle neutron scattering study

Energy Technology Data Exchange (ETDEWEB)

Moussaid, A. (Lab. d' Ultrasons et de Dynamique des Fluides Complexes, Univ. Louis Pasteur, 67 - Strasbourg (France)); Schosseler, F. (Lab. d' Ultrasons et de Dynamique des Fluides Complexes, Univ. Louis Pasteur, 67 - Strasbourg (France)); Munch, J.P. (Lab. d' Ultrasons et de Dynamique des Fluides Complexes, Univ. Louis Pasteur, 67 - Strasbourg (France)); Candau, S.J. (Lab. d' Ultrasons et de Dynamique des Fluides Complexes, Univ. Louis Pasteur, 67 - Strasbourg (France))

1993-04-01

The intensity scattered from polyacrylic acid and polymethacrylic acid solutions has been measured by small angle neutron scattering experiments. The influence of polymer concentration, ionization degree, temperature and salt content has been investigated. Results are in qualitative agreement with a model which predicts the existence of microphases in the unstable region of the phase diagram. Quantitative comparison with the theory is performed by fitting the theoretical structure factor to the experimental data. For a narrow range of ionization degrees nearly quantitative agreement with the theory is found for the polyacrylic acid system. (orig.).

Structure of polyacrylic acid and polymethacrylic acid solutions : a small angle neutron scattering study

Science.gov (United States)

Moussaid, A.; Schosseler, F.; Munch, J. P.; Candau, S. J.

1993-04-01

The intensity scattered from polyacrylic acid and polymethacrylic acid solutions has been measured by small angle neutron scattering experiemnts. The influence of polymer concentration, ionization degree, temperature and salt content has been investigated. Results are in qualitative agreement with a model which predicts the existence of microphases in the unstable region of the phase diagram. Quantitative comparison with the theory is performed by fitting the theoretical structure factor to the experimental data. For a narrow range of ionizaiton degrees nearly quantitative agreement with the theory is found for the polyacrylic acide system.

Alcohol Poisoning Deaths PSA (:60)

Centers for Disease Control (CDC) Podcasts

This 60 second Public Service Announcement is based on the January 2015 CDC Vital Signs report. In the United States, an average of six people die every day from alcohol poisoning. Learn what you can do to prevent binge drinking and alcohol poisoning.

Presentations of patients of poisoning and predictors of poisoning-related fatality: Findings from a hospital-based prospective study

Directory of Open Access Journals (Sweden)

Lin Hung-Jung

2008-01-01

Full Text Available Abstract Background Poisoning is a significant public health problem worldwide and is one of the most common reasons for visiting emergency departments (EDs, but factors that help to predict overall poisoning-related fatality have rarely been elucidated. Using 1512 subjects from a hospital-based study, we sought to describe the demographic and clinical characteristics of poisoning patients and to identify predictors for poisoning-related fatality. Methods Between January 2001 and December 2002 we prospectively recruited poisoning patients through the EDs of two medical centers in southwest Taiwan. Interviews were conducted with patients within 24 hours after admission to collect relevant information. We made comparisons between survival and fatality cases, and used logistic regressions to identify predictors of fatality. Results A total of 1512 poisoning cases were recorded at the EDs during the study period, corresponding to an average of 4.2 poisonings per 1000 ED visits. These cases involved 828 women and 684 men with a mean age of 38.8 years, although most patients were between 19 and 50 years old (66.8%, and 29.4% were 19 to 30 years. Drugs were the dominant poisoning agents involved (49.9%, followed by pesticides (14.5%. Of the 1512 patients, 63 fatalities (4.2% occurred. Paraquat exposure was associated with an extremely high fatality rate (72.1%. The significant predictors for fatality included age over 61 years, insufficient respiration, shock status, abnormal heart rate, abnormal body temperature, suicidal intent and paraquat exposure. Conclusion In addition to well-recognized risk factors for fatality in clinical settings, such as old age and abnormal vital signs, we found that suicidal intent and ingestion of paraquat were significant predictors of poisoning-related fatality. Identification of these predictors may help risk stratification and the development of preventive interventions.

A quasi-elastic neutron scattering and neutron spin-echo study of hydrogen bonded system

Energy Technology Data Exchange (ETDEWEB)

Branca, C.; Faraone, A.; Magazu, S.; Maisano, G.; Mangione, A

2004-07-15

This work reports neutron spin echo results on aqueous solutions of trehalose, a naturally occurring disaccharide of glucose, showing an extraordinary bioprotective effectiveness against dehydration and freezing. We collected data using the SPAN spectrometer (BENSC, Berlin) on trehalose aqueous solutions at different temperature values. The obtained findings are compared with quasi-elastic neutron scattering results in order to furnish new results on the dynamics of the trehalose/water system on the nano and picoseconds scale.

Numerical solution of diffusion equation to study fast neutrons flux distribution for variant radii of nuclear fuel pin and moderator regions

Energy Technology Data Exchange (ETDEWEB)

Mousavi Shirazi, Seyed Alireza [Islamic Azad Univ. (I.A.U.), Dept. of Physics, Tehran (Iran, Islamic Republic of)

2015-07-15

In this symbolic investigation, a cylindrical cell in a LWR, which consists of one fuel pin and moderator (water), is considered. The width of this cylindrical cell is divided into 100 equal units. Since the neutron flux in a cylindrical fuel pin is resulting from the diffusion equation: -(1)/(r)(d)/(dr)Dr(d)/(dr)φ(r) + Σ{sub a}φ(r) = S(r), the amount of fast neutron fluxes are obtained on the basis of the numeric solution of this equation, and the applied boundary conditions are considered: φ'(0) = φ'(1) = 0. This differential equation is solved by the tridiagonal method for variant enrichments of uranium. Neutron fluxes are obtained in variant radii of fuel pin and moderator and are finally compared with each other. There are some interesting outcomes resulting from this investigation. It can be inferred that because of the fuel enrichment increment, the fast neutron flux increases significantly at the centre of core, while many of the fast neutrons produced are absorbed after entering the water region, moderation of lots of them causes the reduced neutron flux to get improved in this region.

14 CFR 137.39 - Economic poison dispensing.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Economic poison dispensing. 137.39 Section... AIRCRAFT OPERATIONS Operating Rules § 137.39 Economic poison dispensing. (a) Except as provided in... economic poison that is registered with the U.S. Department of Agriculture under the Federal Insecticide...

Transdermal carbamate poisoning – a case of misuse

Directory of Open Access Journals (Sweden)

Lalit Kumar Rajbanshi

2017-01-01

Full Text Available Acute pesticide poisoning is a common mode of intentional self harm. Oral ingestion is the usual mode of poisoning. However, inhalation, accidental or occupational transdermal exposure leading to acute or chronic poisoning can be the other route of poisoning. It has been seen that the purpose of poising is suicidal intensity in most of the cases. We report an unusual case where the victim had acute pesticide poisoning through transdermal route that was intended for non suicidal purpose. The patient was managed successfully with immediate decontamination and adequate antidote.

Canadian Neutron Source (CNS): a research reactor solution for medical isotopes and neutrons for science

International Nuclear Information System (INIS)

Chapman, D.

2009-01-01

This presentation describes a dual purpose research facility at the University of Saskatchewan for Canada for the production of medical isotopes and neutrons for scientific research. The proposed research reactor is intended to supply most of Canada's medical isotope requirements and provide a neutron source for Canada's research community. Scientific research would include materials research, biomedical research and imaging.

Benzodiazepine poisoning in elderly

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Perković-Vukčević Nataša

2016-01-01

Full Text Available Background/Aim. Benzodiazepines are among the most frequently ingested drugs in self-poisonings. Elderly may be at greater risk compared with younger individuals due to impaired metabolism and increased sensitivity to benzodiazepines. The aim of this study was to assess toxicity of benzodiazepines in elderly attempted suicide. Methods. A retrospective study of consecutive presentations to hospital after self-poisoning with benzodiazepines was done. Collected data consisted of patient's characteristics (age, gender, benzodiazepine ingested with its blood concentrations at admission, clinical findings including vital signs and Glasgow coma score, routine blood chemistry, complications of poisoning, details of management, length of hospital stay and outcome. According the age, patients are classified as young (15-40-year old, middle aged (41-65-year old and elderly (older than 65. Results. During a 2-year observational period 387 patients were admitted because of pure benzodiazepine poisoning. The most frequently ingested drug was bromazepam, the second was diazepam. The incidence of coma was significantly higher, and the length of hospital stay significantly longer in elderly. Respiratory failure and aspiration pneumonia occurred more frequently in old age. Also, flumazenil was more frequently required in the group of elderly patients. Conclusion. Massive benzodiazepines overdose in elderly may be associated with a significant morbidity, including deep coma with aspiration pneumonia, respiratory failure, and even death. Flumazenil is indicated more often to reduce CNS depression and prevent complications of prolonged unconsciousness, but supportive treatment and proper airway management of comatose patients is the mainstay of the treatment of acute benzodiazepine poisoning.

Benzodiazepine poisoning in elderly

OpenAIRE

Perković-Vukčević Nataša; Vuković-Ercegović Gordana; Šegrt Zoran; Đorđević Snežana; Jović-Stošić Jasmina

2016-01-01

Background/Aim. Benzodiazepines are among the most frequently ingested drugs in self-poisonings. Elderly may be at greater risk compared with younger individuals due to impaired metabolism and increased sensitivity to benzodiazepines. The aim of this study was to assess toxicity of benzodiazepines in elderly attempted suicide. Methods. A retrospective study of consecutive presentations to hospital after self-poisoning with benzodiazepines was done. Collecte...

VENENO-PONZOÑA, ENVENENAMIENTO-EMPONZOÑAMIENTO, ANIMALES VENENOSOS-ANIMALES PONZOÑOSOS: ¿CUÁLES SON LAS DIFERENCIAS? | VENOM-POISON, ENVENOMATION-POISONING, VENOMOUS ANIMALS-POISONOUS ANIMALS: WHAT ARE THE DIFFERENCES?

Directory of Open Access Journals (Sweden)

Dalmiro Cazorla-Perfetti

2016-08-01

Full Text Available In the specialized scientific literature of Latin America, the terms venom and poison, envenomation and poisoning, venomous animals and poisonous animals are frequently implemented improperly as synonyms. Thus, in the present communication the differences of these terms are discussed in the context of the Clinical Toxinology lexic and the need for homogenizing such a nomenclature is highlighted.

Ciguatera and scombroid fish poisoning in the United States.

Science.gov (United States)

Pennotti, Radha; Scallan, Elaine; Backer, Lorraine; Thomas, Jerry; Angulo, Frederick J

2013-12-01

Ciguatera and scombroid fish poisonings are common causes of fish-related foodborne illness in the United States; however, existing surveillance systems underestimate the overall human health impact. This study aimed to describe existing data on ciguatera and scombroid fish poisonings from outbreak and poison control center reports and to estimate the overall number of ciguatera and scombroid fish-poisoning illnesses, hospitalizations, and deaths in the United States. We analyzed outbreak data from the Foodborne Disease Outbreak Surveillance Systems (FDOSS) from 2000 to 2007 and poison control center call data from the National Poison Data System (NPDS) from 2005 to 2009 for reports of ciguatera and scombroid fish poisonings. Using a statistical model with many inputs, we adjusted the outbreak data for undercounting due to underreporting and underdiagnosis to generate estimates. Underreporting and underdiagnosis multipliers were derived from the poison control call data and the published literature. Annually, an average of 15 ciguatera and 28 scombroid fish-poisoning outbreaks, involving a total of 60 and 108 ill persons, respectively, were reported to FDOSS (2000-2007). NPDS reported an average of 173 exposure calls for ciguatoxin and 200 exposure calls for scombroid fish poisoning annually (2005-2009). After adjusting for undercounting, we estimated 15,910 (90% credible interval [CrI] 4140-37,408) ciguatera fish-poisoning illnesses annually, resulting in 343 (90% CrI 69-851) hospitalizations and three deaths (90% CrI 1-7). We estimated 35,142 (90% CrI: 10,496-78,128) scombroid fish-poisoning illnesses, resulting in 162 (90% CrI 0-558) hospitalizations and 0 deaths. Ciguatera and scombroid fish poisonings affect more Americans than reported in surveillance systems. Although additional data can improve these assessments, the estimated number of illnesses caused by seafood intoxication illuminates this public health problem. Efforts, including education, can reduce

Depletion optimization of lumped burnable poisons in pressurized water reactors

International Nuclear Information System (INIS)

Kodah, Z.H.

1982-01-01

Techniques were developed to construct a set of basic poison depletion curves which deplete in a monotonical manner. These curves were combined to match a required optimized depletion profile by utilizing either linear or non-linear programming methods. Three computer codes, LEOPARD, XSDRN, and EXTERMINATOR-2 were used in the analyses. A depletion routine was developed and incorporated into the XSDRN code to allow the depletion of fuel, fission products, and burnable poisons. The Three Mile Island Unit-1 reactor core was used in this work as a typical PWR core. Two fundamental burnable poison rod designs were studied. They are a solid cylindrical poison rod and an annular cylindrical poison rod with water filling the central region.These two designs have either a uniform mixture of burnable poisons or lumped spheroids of burnable poisons in the poison region. Boron and gadolinium are the two burnable poisons which were investigated in this project. Thermal self-shielding factor calculations for solid and annular poison rods were conducted. Also expressions for overall thermal self-shielding factors for one or more than one size group of poison spheroids inside solid and annular poison rods were derived and studied. Poison spheroids deplete at a slower rate than the poison mixture because each spheroid exhibits some self-shielding effects of its own. The larger the spheroid, the higher the self-shielding effects due to the increase in poison concentration

Self-harm and self-poisoning in southern India

DEFF Research Database (Denmark)

Bose, Anuradha; Sandal Sejbaek, Camilla; Suganthy, Pearline

2009-01-01

over a period of 2 years. RESULTS AND CONCLUSION: The overall suicide rate was 71.4 per 100 000 population; the highest burden was among men. Most people died through hanging (81, 54%) and self-poisoning (46, 31%). Of the 46 who died from self-poisoning, 78.3% had taken pesticides and 19.7% had eaten...... poisonous plants. Eighty per cent of the self-poisoning cases obtained the poisonous substance in or in close proximity to the home, highlighting the importance of safe storage in the domestic environment. Of the 110 fatal and non-fatal self-poisoning cases, 87 (57.5%) were taken for treatment; 50 (57.......4%) went to government hospitals and 37 (42.5%) to private facilities. This indicates the importance of including the private sector in the efforts to improve case management. Furthermore, the fact that 31 (67%) of the self-poisoning patients, who eventually died, were alive after 4 h provides an incentive...

Theoretical analysis of nuclear reactors (Phase II), I-V, Part III, Reactor poisoning; Razrada metoda teorijske analize nuklearnih reaktora (II faza) I-V, III Deo, Zatrovanje reaktora, II faza

Energy Technology Data Exchange (ETDEWEB)

Pop-Jordanov, J [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Serbia and Montenegro)

1962-10-15

This phase is dealing with influence of all the fission products except Xe{sup 135} on the reactivity of a reactor, usually named as reactor poisoning. The first part of the report is a review of methods for calculation of reactor poisoning. The second part shows the most frequently used method for calculation of cross sections and yields of pseudo products (for thermal neutrons). The system of equations was adopted dependent on the conditions of the available computer system. It is described in part three. Detailed method for their application is described in part four and results obtained are presented in part five.

Cardiac Glycoside Plants Self-Poisoning

Directory of Open Access Journals (Sweden)

Radenkova-Saeva J.

2014-06-01

Full Text Available Cardiac glycosides are found in a diverse group of plants including Digitalis purpurea and Digitalis lanata (foxgloves, Nerium oleander, Convallaria majalis (lily of the valley, Strophanthus gratus, etc. Nerium Oleander is an indoor and ornamental plant of an evergreen shrub. It’s widespread in countries with a Mediterranean climate. Oleander is one of the most poisonous plants known to humans. All parts of the nerium oleander are poisonous, primarily due to the contained cardiac glycosides - oleandrin, nerin, digitoxigenin, and olinerin of which oleandrin is the principal toxin. The bark contains the toxic substances of rosagenin which causes strychnine-like effects. Signs of poisoning appear a few hours after the adoption of the parts of the plant. Two cases of Nerium Oleander poisoning were presented. Clinical picture included gastrointestinal, cardiovascular and central nervous system effects. The clinical symptoms were characterized by nausea, vomiting, salivation, colic, diarrhoea, ventricular tachycardia, dysrhythmia, heart block, ataxia, drowsiness, muscular tremor. Treatment included administration of activated charcoal, symptomatic and supportive care.

Coarse-grain parallel solution of few-group neutron diffusion equations

International Nuclear Information System (INIS)

Sarsour, H.N.; Turinsky, P.J.

1991-01-01

The authors present a parallel numerical algorithm for the solution of the finite difference representation of the few-group neutron diffusion equations. The targeted architectures are multiprocessor computers with shared memory like the Cray Y-MP and the IBM 3090/VF, where coarse granularity is important for minimizing overhead. Most of the work done in the past, which attempts to exploit concurrence, has concentrated on the inner iterations of the standard outer-inner iterative strategy. This produces very fine granularity. To coarsen granularity, the authors introduce parallelism at the nested outer-inner level. The problem's spatial domain was partitioned into contiguous subregions and assigned a processor to solve for each subregion independent of all other subregions, hence, processors; i.e., each subregion is treated as a reactor core with imposed boundary conditions. Since those boundary conditions on interior surfaces, referred to as internal boundary conditions (IBCs), are not known, a third iterative level, the recomposition iterations, is introduced to communicate results between subregions

Pre-hospital treatment of acute poisonings in Oslo

Science.gov (United States)

Heyerdahl, Fridtjof; Hovda, Knut E; Bjornaas, Mari A; Nore, Anne K; Figueiredo, Jose CP; Ekeberg, Oivind; Jacobsen, Dag

2008-01-01

Background Poisoned patients are often treated in and discharged from pre-hospital health care settings. Studies of poisonings should therefore not only include hospitalized patients. Aims: To describe the acutely poisoned patients treated by ambulance personnel and in an outpatient clinic; compare patients transferred to a higher treatment level with those discharged without transfer; and study the one-week mortality after pre-hospital discharge. Methods A one-year multi-centre study with prospective inclusion of all acutely poisoned patients ≥ 16 years of age treated in ambulances, an outpatient clinic, and hospitals in Oslo. Results A total of 3757 health service contacts from 2997 poisoning episodes were recorded: 1860 were treated in ambulances, of which 15 died and 750 (40%) were discharged without transfer; 956 were treated in outpatient clinic, of which 801 (84%) were discharged without transfer; and 941 episodes were treated in hospitals. Patients discharged alive after ambulance treatment were mainly poisoned by opiates (70%), were frequently comatose (35%), had respiratory depression (37%), and many received naloxone (49%). The majority of the patients discharged from the outpatient clinic were poisoned by ethanol (55%), fewer were comatose (10%), and they rarely had respiratory depression (4%). Among the hospitalized, pharmaceutical poisonings were most common (58%), 23% were comatose, and 7% had respiratory depression. Male patients comprised 69% of the pre-hospital discharges, but only 46% of the hospitalized patients. Except for one patient, who died of a new heroin overdose two days following discharge from an ambulance, there were no deaths during the first week after the poisonings in the 90% of the pre-hospital discharged patients with known identity. Conclusion More than half of the poisoned patients treated in pre-hospital treatment settings were discharged without transfer to higher levels. These poisonings were more often caused by drug and

Pre-hospital treatment of acute poisonings in Oslo

Directory of Open Access Journals (Sweden)

Nore Anne K

2008-11-01

Full Text Available Abstract Background Poisoned patients are often treated in and discharged from pre-hospital health care settings. Studies of poisonings should therefore not only include hospitalized patients. Aims: To describe the acutely poisoned patients treated by ambulance personnel and in an outpatient clinic; compare patients transferred to a higher treatment level with those discharged without transfer; and study the one-week mortality after pre-hospital discharge. Methods A one-year multi-centre study with prospective inclusion of all acutely poisoned patients ≥ 16 years of age treated in ambulances, an outpatient clinic, and hospitals in Oslo. Results A total of 3757 health service contacts from 2997 poisoning episodes were recorded: 1860 were treated in ambulances, of which 15 died and 750 (40% were discharged without transfer; 956 were treated in outpatient clinic, of which 801 (84% were discharged without transfer; and 941 episodes were treated in hospitals. Patients discharged alive after ambulance treatment were mainly poisoned by opiates (70%, were frequently comatose (35%, had respiratory depression (37%, and many received naloxone (49%. The majority of the patients discharged from the outpatient clinic were poisoned by ethanol (55%, fewer were comatose (10%, and they rarely had respiratory depression (4%. Among the hospitalized, pharmaceutical poisonings were most common (58%, 23% were comatose, and 7% had respiratory depression. Male patients comprised 69% of the pre-hospital discharges, but only 46% of the hospitalized patients. Except for one patient, who died of a new heroin overdose two days following discharge from an ambulance, there were no deaths during the first week after the poisonings in the 90% of the pre-hospital discharged patients with known identity. Conclusion More than half of the poisoned patients treated in pre-hospital treatment settings were discharged without transfer to higher levels. These poisonings were more often

Extracorporeal treatment for tricyclic antidepressant poisoning

DEFF Research Database (Denmark)

Yates, Christopher; Galvao, Tais; Sowinski, Kevin M

2014-01-01

The Extracorporeal Treatments In Poisoning (EXTRIP) workgroup was formed to provide recommendations on the use of extracorporeal treatments (ECTR) in poisoning. Here, the workgroup presents its results for tricyclic antidepressants (TCAs). After an extensive literature search, using a predefined...... methodology, the subgroup responsible for this poison reviewed the articles, extracted the data, summarized findings, and proposed structured voting statements following a predetermined format. A two-round modified Delphi method was chosen to reach a consensus on voting statements and RAND...... yielding a very low quality of evidence for all recommendations. Data on 108 patients, including 12 fatalities, were abstracted. The workgroup concluded that TCAs are not dialyzable and made the following recommendation: ECTR is not recommended in severe TCA poisoning (1D). The workgroup considers...

Evaluation of processed borax as antidote for aconite poisoning.

Science.gov (United States)

Sarkar, Prasanta Kumar; Prajapati, Pradeep K; Shukla, Vinay J; Ravishankar, Basavaiah

2017-06-09

Aconite root is very poisonous; causes cardiac arrhythmias, ventricular fibrillation and ventricular tachycardia. There is no specific antidote for aconite poisoning. In Ayurveda, dehydrated borax is mentioned for management of aconite poisoning. The investigation evaluated antidotal effect of processed borax against acute and sub-acute toxicity, cardiac toxicity and neuro-muscular toxicity caused by raw aconite. For acute protection Study, single dose of toxicant (35mg/kg) and test drug (22.5mg/kg and 112.5mg/kg) was administered orally, and then 24h survival of animals was observed. The schedule was continued for 30 days in sub-acute protection Study with daily doses of toxicant (6.25mg/kg), test drug (22.5mg/kg and 112.5mg/kg) and vehicle. Hematological and biochemical tests of blood and serum, histopathology of vital organs were carried out. The cardiac activity Study was continued for 30 days with daily doses of toxicant (6.25mg/kg), test drug (22.5mg/kg), processed borax solution (22.5mg/kg) and vehicle; ECG was taken after 1h of drug administration on 1 TB , 15th and on 30th day. For neuro-muscular activity Study, the leech dorsal muscle response to 2.5µg of acetylcholine followed by response of toxicant at 25µg and 50µg doses and then response of test drug at 25µg dose were recorded. Protection index indicates that treated borax gave protection to 50% rats exposed to the lethal dose of toxicant in acute protection Study. Most of the changes in hematological, biochemical parameters and histopathological Study induced by the toxicant in sub-acute protection Study were reversed significantly by the test drug treatment. The ventricular premature beat and ventricular tachyarrhythmia caused by the toxicant were reversed by the test drug indicate reversal of toxicant induced cardio-toxicity. The acetylcholine induced contractions in leech muscle were inhibited by toxicant and it was reversed by test drug treatment. The processed borax solution is found as an

Extracorporeal treatment for acetaminophen poisoning

DEFF Research Database (Denmark)

Gosselin, S; Juurlink, D N; Kielstein, J T

2014-01-01

BACKGROUND: The Extracorporeal Treatments in Poisoning (EXTRIP) workgroup was created to provide evidence-based recommendations on the use of extracorporeal treatments (ECTR) in poisoning and the results are presented here for acetaminophen (APAP). METHODS: After a systematic review of the litera...... of NAC has not been definitively demonstrated....

Poisonous plants in New Zealand: a review of those that are most commonly enquired about to the National Poisons Centre.

Science.gov (United States)

Slaughter, Robin J; Beasley, D Michael G; Lambie, Bruce S; Wilkins, Gerard T; Schep, Leo J

2012-12-14

New Zealand has a number of plants, both native and introduced, contact with which can lead to poisoning. The New Zealand National Poisons Centre (NZNPC) frequently receives enquiries regarding exposures to poisonous plants. Poisonous plants can cause harm following inadvertent ingestion, via skin contact, eye exposures or inhalation of sawdust or smoked plant matter. The purpose of this article is to determine the 15 most common poisonous plant enquiries to the NZNPC and provide a review of current literature, discussing the symptoms that might arise upon exposure to these poisonous plants and the recommended medical management of such poisonings. Call data from the NZNPC telephone collection databases regarding human plant exposures between 2003 and 2010 were analysed retrospectively. The most common plants causing human poisoning were selected as the basis for this review. An extensive literature review was also performed by systematically searching OVID MEDLINE, ISI Web of Science, Scopus and Google Scholar. Further information was obtained from book chapters, relevant news reports and web material. For the years 2003-2010 inclusive, a total of 256,969 enquiries were received by the NZNPC. Of these enquiries, 11,049 involved exposures to plants and fungi. The most common poisonous plant enquiries, in decreasing order of frequency, were: black nightshade (Solanum nigrum), arum lily (Zantedeschia aethiopica), kowhai (Sophora spp.), euphorbia (Euphorbia spp.), peace lily (Spathiphyllum spp.), agapanthus (Agapanthus spp.), stinking iris (Iris foetidissima), rhubarb (Rheum rhabarbarum), taro (Colocasia esculentum), oleander (Nerium oleander), daffodil (Narcissus spp.), hemlock (Conium maculatum), karaka (Corynocarpus laevigatus), foxglove (Digitalis purpurea) and ongaonga/New Zealand tree nettle (Urtica ferox). The combined total of enquiries for these 15 species was 2754 calls (representing approximately 25% of all enquiries regarding plant exposures). The signs

Toad poisoning in three dogs: case reports

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CM Barbosa

2009-01-01

Full Text Available Toad poisoning is frequent in dogs, but has been infrequently addressed in published case reports and review articles. Dogs can be poisoned when they bite a toad or otherwise ingest the venom. The venom effects manifest soon after the accident, since the toxin is rapidly absorbed by the mucous membrane of the digestive system. Hospital records of three dogs, diagnosed with toad poisoning, were retrospectively reviewed from January 2005 to July 2007. Poisoned dogs may present only local irritation or systemic signs in the gastrointestinal, cardiac and neurological systems. All three cases presented herein had clinical signs of gastrointestinal alterations including vomiting, sialorrhea and diarrhea. Two dogs developed abnormal cardiac rhythm and two exhibited neurological signs. A poisoned animal requires emergency care and symptomatic therapy with intense monitoring of its clinical parameters. Although there have been reports on the low mortality of dogs poisoned by toads, one animal died even after appropriate therapy. The severity of clinical signs and the risk of death must be considered by the veterinarian.

An Outbreak of Foxglove Leaf Poisoning

Directory of Open Access Journals (Sweden)

Chun-Chi Lin

2010-02-01

Full Text Available Comfrey (Symphytum officinale leaves resemble those of foxglove (Digitalis purpurea when the plant is not in bloom and, therefore, cardiac glycoside poisoning may occur when people confuse foxglove with comfrey. We report an outbreak of foxglove leaf poisoning following the use of alleged “comfrey” herbal tea. Nine patients were involved and initially presented with nausea, vomiting, diarrhea and dizziness. Significant cardiotoxicity developed later among the 3 patients who also had mild hyperkalemia. Peak serum digoxin concentration measured by immunoassay was elevated in all patients and ranged from 4.4 ng/mL to 139.5 ng/mL. Patients with severe cardiotoxicity were treated with temporary cardiac pacing. Moreover, 40–80 mg of digoxin-specific antibody therapy was given without any effect. All patients recovered uneventfully. Our report highlights the potential risk of misidentification of herbs; in this case, D. purpurea was mistaken for S. officinale. Physicians should be aware that cardiac glycoside poisoning could arise from such misidentification. Public education about the toxicity of D. purpurea poisoning may reduce the risk of misidentification and subsequent poisoning.

Burnable poison management in a HTR

Energy Technology Data Exchange (ETDEWEB)

Pedersen, J

1971-09-21

It is the purpose with this paper to describe the state-of-the-art of burnable poison investigations made within the Dragon Project and to give the results of a number of calculations, which show that it is possible to control the large initial surplus reactivity of the first core and the radial power distribution with two types of burnable poison sticks with Gadolinium (one type of stick to be used in the inner core region, the other in the outer core region), where the poison will burn away so that keff always stays around the desired value 1.03, and with the radial form-factor not exceeding 1.20. The calculations made for this paper are not too accurate, especially the chosen timestep for calculating the burn-up of the burnable poison stick proved to be too large. Nevertheless, the calculations are good enough to draw the above mentioned conclusions, although they have not given the concentration of Gadolinium to be used in the burnable poison sticks very accurately.

Is Your Child Safe from Lead Poisoning?

Centers for Disease Control (CDC) Podcasts

2008-10-02

In this podcast, Dr. Mary Jean Brown, chief of CDC's Lead Poisoning and Prevention Program, discusses the importance of testing children for lead poisoning, who should be tested, and what parents can do to prevent lead poisoning.  Created: 10/2/2008 by National Center for Environmental Health (NCEH).   Date Released: 10/2/2008.

Is poisoning a problem in South Sudan?

African Journals Online (AJOL)

2011-11-04

Nov 4, 2011 ... (e.g. mesothelioma caused by contact with asbestos). Criminal act of poisoning: e.g. “spiking” of a drink at a party. Poisoning in uganda. When I was working in Uganda I saw several cases of poisoning with organophosphates and was horrified by the mortality. Almost ten years ago, we carried out a simple.

Alcohol Withdrawal Mimicking Organophosphate Poisoning

Directory of Open Access Journals (Sweden)

Nezihat Rana Disel

2014-02-01

Full Text Available Organophosphates, which can cause occupational poisoning due to inappropriate personal protective measures, are widely used insecticides in agricultural regions of southern Turkey. Therefore, the classical clinical findings of this cholinergic poisoning are myosis, excessive secretions, bradicardia and fasciculations are easy to be recognized by local medical stuff. Diseases and conditions related to alcoholism such as mental and social impairments, coma, toxicity, withdrawal, and delirium are frequent causes of emergency visits of chronic alcoholic patients. Here we present a case diagnosed and treated as organophosphate poisoning although it was an alcohol withdrawal in the beginning and became delirium tremens, due to similar symptoms.

Acetone poisoning

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/002480.htm Acetone poisoning To use the sharing features on this page, please enable JavaScript. Acetone is a chemical used in many household products. ...

Carbon Monoxide Poisoning in Children

Directory of Open Access Journals (Sweden)

Chi-Hsiun Cho

2008-08-01

Conclusion: Children with CO poisoning had good outcomes in this series. Although improperly vented exhaust from water heaters and house fires were the most common causes, intentional poisoning by parents through charcoal burning was also an important factor. Early identification of DNS risk factors might help to provide better care.

Neutron-scattering study of the vibrational behavior of trehalose aqueous solutions

Energy Technology Data Exchange (ETDEWEB)

Branca, C.; Magazu, S.; Migliardo, F.; Romeo, G.; Villari, V.; Wanderlingh, U. [Dipartimento di Fisica and INFM, Universita' di Messina, PO Box 55, 98166 Messina (Italy); Colognesi, D. [DRAL-ISIS,Chilton, Oxford OX1 3PU (United Kingdom)

2002-07-01

Neutron spectra for hydrated trehalose samples have been obtained by using the time-of-flight spectrometer TOSCA at the ISIS Pulse Neutron Facility (Rutherford Appleton Laboratory, Chilton, UK). Neutron spectra have been compared to the absorbance spectra obtained by Fourier-transform infrared spectroscopy. Finally, a comparison with findings obtained by density functional theory has been performed. (orig.)

Electrochemical Corrosion Testing of Neutron Absorber Materials

International Nuclear Information System (INIS)

Tedd Lister; Ron Mizia; Sandra Birk; Brent Matteson; Hongbo Tian

2006-01-01

The Yucca Mountain Project (YMP) has been directed by DOE-RW to develop a new repository waste package design based on the transport, aging, and disposal canister (TAD) system concept. A neutron poison material for fabrication of the internal spent nuclear fuel (SNF) baskets for these canisters needs to be identified. A material that has been used for criticality control in wet and dry storage of spent nuclear fuel is borated stainless steel. These stainless products are available as an ingot metallurgy plate product with a molybdenum addition and a powder metallurgy product that meets the requirements of ASTM A887, Grade A. A new Ni-Cr-Mo-Gd alloy has been developed by the Idaho National Laboratory (INL) with its research partners (Sandia National Laboratory and Lehigh University) with DOE-EM funding provided by the National Spent Nuclear Fuel Program (NSNFP). This neutron absorbing alloy will be used to fabricate the SNF baskets in the DOE standardized canister. The INL has designed the DOE Standardized Spent Nuclear Fuel Canister for the handling, interim storage, transportation, and disposal in the national repository of DOE owned spent nuclear fuel (SNF). A corrosion testing program is required to compare these materials in environmental conditions representative of a breached waste canister. This report will summarize the results of crevice corrosion tests for three alloys in solutions representative of ionic compositions inside the waste package should a breech occur. The three alloys in these tests are Neutronit A978 (ingot metallurgy, hot rolled), Neutrosorb 304B4 Grade A (powder metallurgy, hot rolled), and Ni-Cr-Mo-Gd alloy (ingot metallurgy, hot rolled)

The Effect Of Beryllium Interaction With Fast Neutrons On the Reactivity Of ETRR-2 Research Reactor

International Nuclear Information System (INIS)

Aziz, M.; El Messiry, A.M.

2000-01-01

The effect of beryllium interactions with fast neutrons is studied for Etrr 2 research reactors. Isotope build up inside beryllium blocks is calculated under different irradiation times. a new model for the Etrr 2 research reactor is designed using MCNP code to calculate the reactivity and flux change of the reactor due to beryllium poison

Amitraz poisoning: case report

Directory of Open Access Journals (Sweden)

Jaime Alexander Molina-Bolaños

2017-10-01

Full Text Available Amitraz is an insecticide compound used worldwide for controlling pests, especially in agricultural and livestock areas. However, amitraz poisoning in Colombia is rare. This article reports the case of an 18-year-old female patient who was admitted in the emergency service 3 hours after the intake of an unknown amount of Triatox® (amitraz. The patient presented with a depressed level of consciousness, respiratory distress, hypotension, bradycardia, myosis and metabolic acidosis compensated with respiratory alkalosis. Initial treatment was provided using life support measures in the emergency ward, and subsequent transfer and support in the intensive care unit. She was discharged 24 hours after admission. This case considers the clinical similarity between amitraz poisoning and poisoning caused by other more frequent toxic compounds such as carbamates, organophosphates and opioids, which require different management.

A fully algebraic solution for multichannel scattering of neutrons from nuclei

International Nuclear Information System (INIS)

Amos, K.

2001-01-01

In this report I give the prescription by which an algebraic solution can be found for multichannel scattering of neutrons from nuclei. The theory, developed by the Padova group, is built upon the work of Rawitscher and Delic. The approach is predicated upon finite rank representations of realistic interaction potentials and the properties of scattering matrices for separable Schrodinger interactions. The Padova approach starts with a solvable auxiliary Sturmian function (Weinberg state) problem from which a first generation set of Sturmians are defined. That basis set is formed by choosing a solvable problem at a fixed negative energy, and thereby those Sturmians can be specified in closed analytic form. Second generation Sturmians built upon the interaction potential matrices for a multichannel scattering problem of interest then can be found as linear combinations of the first generation set. The expansion coefficients result from a matrix diagonalization process. The scheme enables an expansion (usually truncated to finite rank for convenience) of the interaction potential in terms of those second generation Sturmians and in the form of a sum of separable interactions. The analytic properties of the scattering matrix from a separable Schroedinger potential gives the means by which a full algebraic solution of the multichannel scattering problem can be realized. (author)

Neutron Absorbing Ability Variation in Neutron Absorbing Material Caused by the Neutron Irradiation in Spent Fuel Storage Facility

Energy Technology Data Exchange (ETDEWEB)

Sohn, Hee Dong; Han, Seul Gi; Lee, Sang Dong; Kim, Ki Hong; Ryu, Eag Hyang; Park, Hwa Gyu [Doosan Heavy Industries and Construction, Changwon (Korea, Republic of)

2014-10-15

In spent fuel storage facility like high density spent fuel storage racks and dry storage casks, spent fuels are stored with neutron absorbing materials installed as a part of those facilities, and they are used for absorbing neutrons emitted from spent fuels. Usually structural material with neutron absorbing material of racks and casks are located around spent fuels, so it is irradiated by neutrons for long time. Neutron absorbing ability could be changed by the variation of nuclide composition in neutron absorbing material caused by the irradiation of neutrons. So, neutron absorbing materials are continuously faced with spent fuels with boric acid solution or inert gas environment. Major nuclides in neutron absorbing material are Al{sup 27}, C{sup 12}, B{sup 11}, B{sup 10} and they are changed to numerous other ones as radioactive decay or neutron absorption reaction. The B{sup 10} content in neutron absorbing material dominates the neutron absorbing ability, so, the variation of nuclide composition including the decrease of B{sup 10} content is the critical factor on neutron absorbing ability. In this study, neutron flux in spent fuel, the activation of neutron absorbing material and the variation of nuclide composition are calculated. And, the minimum neutron flux causing the decrease of B{sup 10} content is calculated in spent fuel storage facility. Finally, the variation of neutron multiplication factor is identified according to the one of B{sup 10} content in neutron absorbing material. The minimum neutron flux to impact the neutron absorbing ability is 10{sup 10} order, however, usual neutron flux from spent fuel is 10{sup 8} order. Therefore, even though neutron absorbing material is irradiated for over 40 years, B{sup 10} content is little decreased, so, initial neutron absorbing ability could be kept continuously.

Neutron dosimetry; Dosimetria de neutrons

Energy Technology Data Exchange (ETDEWEB)

Fratin, Luciano

1993-12-31

A neutron irradiation facility was designed and built in order to establish a procedure for calibrating neutron monitors and dosemeters. A 185 GBq {sup 241} Am Be source of known is used as a reference source. The irradiation facility using this source in the air provides neutron dose rates between 9 nSv s{sup -1} and 0,5 {sup {mu}}Sv s{sup -1}. A calibrated 50 nSv s{sup -1} thermal neutron field is obtained by using a specially designed paraffin block in conjunction with the {sup 241} Am Be source. A Bonner multisphere spectrometer was calibrated, using a procedure based on three methods proposed by international standards. The unfold {sup 241} Am Be neutron spectrum was determined from the Bonner spheres data and resulted in a good agreement with expected values for fluence rate, dose rate and mean energy. A dosimetric system based on the electrochemical etching of CR-39 was developed for personal dosimetry. The dosemeter badge using a (n,{alpha}) converter, the etching chamber and high frequency power supply were designed and built specially for this project. The electrochemical etching (ECE) parameters used were: a 6N KOH solution, 59 deg C, 20 kV{sub pp} cm{sup -1}, 2,0 kHz, 3 hours of ECE for thermal and intermediate neutrons and 6 hours for fast neutrons. The calibration factors for thermal, intermediate and fast neutrons were determined for this personal dosemeter. The sensitivities determined for the developed dosimetric system were (1,46{+-} 0,09) 10{sup 4} tracks cm{sup -2} mSv{sup -1} for thermal neutrons, (9{+-}3) 10{sup 2} tracks cm{sup -2} mSV{sup -1} for intermediate neutrons and (26{+-}4) tracks cm{sup -2} mSv{sup -1} for fast neutrons. The lower and upper limits of detection were respectively 0,002 mSv and 0,6 mSv for thermal neutrons, 0,04 mSv and 8 mSv for intermediate neutrons and 1 mSv and 12 mSv for fast neutrons. In view of the 1990`s ICRP recommendations, it is possible to conclude that the personal dosemeter described in this work is

Neutron dosimetry; Dosimetria de neutrons

Energy Technology Data Exchange (ETDEWEB)

Fratin, Luciano

1994-12-31

A neutron irradiation facility was designed and built in order to establish a procedure for calibrating neutron monitors and dosemeters. A 185 GBq {sup 241} Am Be source of known is used as a reference source. The irradiation facility using this source in the air provides neutron dose rates between 9 nSv s{sup -1} and 0,5 {sup {mu}}Sv s{sup -1}. A calibrated 50 nSv s{sup -1} thermal neutron field is obtained by using a specially designed paraffin block in conjunction with the {sup 241} Am Be source. A Bonner multisphere spectrometer was calibrated, using a procedure based on three methods proposed by international standards. The unfold {sup 241} Am Be neutron spectrum was determined from the Bonner spheres data and resulted in a good agreement with expected values for fluence rate, dose rate and mean energy. A dosimetric system based on the electrochemical etching of CR-39 was developed for personal dosimetry. The dosemeter badge using a (n,{alpha}) converter, the etching chamber and high frequency power supply were designed and built specially for this project. The electrochemical etching (ECE) parameters used were: a 6N KOH solution, 59 deg C, 20 kV{sub pp} cm{sup -1}, 2,0 kHz, 3 hours of ECE for thermal and intermediate neutrons and 6 hours for fast neutrons. The calibration factors for thermal, intermediate and fast neutrons were determined for this personal dosemeter. The sensitivities determined for the developed dosimetric system were (1,46{+-} 0,09) 10{sup 4} tracks cm{sup -2} mSv{sup -1} for thermal neutrons, (9{+-}3) 10{sup 2} tracks cm{sup -2} mSV{sup -1} for intermediate neutrons and (26{+-}4) tracks cm{sup -2} mSv{sup -1} for fast neutrons. The lower and upper limits of detection were respectively 0,002 mSv and 0,6 mSv for thermal neutrons, 0,04 mSv and 8 mSv for intermediate neutrons and 1 mSv and 12 mSv for fast neutrons. In view of the 1990`s ICRP recommendations, it is possible to conclude that the personal dosemeter described in this work is

Cutting system for burnable poison rod

International Nuclear Information System (INIS)

Shiina, Atsushi; Toyama, Norihide; Koshino, Yasuo; Fujii, Toshio

1989-01-01

Burnable poison rods attached to spent fuels are contained in a containing box and transported to a receiving pool. The burnable poison rod-containing box is provisionally situated by the operation to a handling device to a provisional setting rack in a cutting pool and attached to a cutting guide of a cutting device upon cutting. The burnable poison rod is cut only in a cutting pool water and tritium generated upon cutting is dissolved into the cutting pool water. Diffusion of tritium is thus restricted. Further, the cutting pool is isolated by a partition device from the receiving pool during cutting of the burnable poison rod. Accordingly, water in which tritium is dissolved is inhibited from moving to the receiving pool and prevail of tritium contamination can be avoided. (T.M.)

Snakebite poisoning in Spain.

Science.gov (United States)

Martín-Sierra, Cristina; Nogué-Xarau, Santiago; Pinillos Echeverría, Miguel Ángel; Rey Pecharromán, José Miguel

2018-01-01

Emergencies due to snakebites, although unusual in Spain, are potentially serious. Of the 13 species native to the Iberian peninsula, only 5 are poisonous: 2 belong to the Colubridae family and 3 to the Viperidae family. Bites from these venemous snakes can be life-threatening, but the venomous species can be easily identified by attending to certain physical traits. Signs denoting poisoning from vipers, and the appropriate treatment to follow, have changed in recent years.

Part A. Neutron activation analysis of selenium and vanadium in biological matrices. Part B. Isomeric transition activation in aqueous solutions of alkyl bromides

International Nuclear Information System (INIS)

Ebrahim, A.

1988-01-01

Several procedures were evaluated for determination of selenium in biological fluids and vanadium in biological tissues by neutron activation analysis (NAA) employing 77m Se and 52 V isotopes, respectively. Procedures for determination of total selenium, trimethylselenonium (TMSe) ion and selenite (SeO 3 2- ) ion in urine and serum and for total selenoamino acids in urine were developed by utilizing anion exchange chromatography and molecular NAA. A pre-column derivatization of selenoamino acids with o-phthalaldehyde was necessary for their determination. Also an analytical approach was developed for determination of trace vanadium in liver samples from normal and diabetic rats as well as human and cow. Reactions of bromine-80 activated by radiative neutron capture and bromine-82 activated by isomeric transition were investigated in aqueous solutions of bromomethane and 1-bromobutane. Bromine-80 organic yields decreased with decreasing solute concentrations. The tendency for aggregation of the solute molecules diminished as the solute concentration approached zero where the probable state of the solute approached a monomolecular dispersion. Unlike reactions of 80 Br born by 79 Br(n,γ) 80 Br reaction, the total organic product yields resulting from the 82m Br(I.T.) 82 Br process showed no solute concentration dependence

Simulations of a PSD Plastic Neutron Collar for Assaying Fresh Fuel

Energy Technology Data Exchange (ETDEWEB)

Hausladen, Paul [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Newby, Jason [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); McElroy, Robert Dennis [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2016-11-01

The potential performance of a notional active coincidence collar for assaying uranium fuel based on segmented detectors constructed from the new PSD plastic fast organic scintillator with pulse shape discrimination capability was investigated in simulation. Like the International Atomic Energy Agency's present Uranium Neutron Collar for LEU (UNCL), the PSD plastic collar would also function by stimulating fission in the ²³⁵U content of the fuel with a moderated ²⁴¹Am/Li neutron source and detecting instances of induced fission via neutron coincidence counting. In contrast to the moderated detectors of the UNCL, the fast time scale of detection in the scintillator eliminates statistical errors due to accidental coincidences that limit the performance of the UNCL. However, the potential to detect a single neutron multiple times historically has been one of the properties of organic scintillator detectors that has prevented their adoption for international safeguards applications. Consequently, as part of the analysis of simulated data, a method was developed by which true neutron-neutron coincidences can be distinguished from inter-detector scatter that takes advantage of the position and timing resolution of segmented detectors. Then, the performance of the notional simulated coincidence collar was evaluated for assaying a variety of fresh fuels, including some containing burnable poisons and partial defects. In these simulations, particular attention was paid to the analysis of fast mode measurements. In fast mode, a Cd liner is placed inside the collar to shield the fuel from the interrogating source and detector moderators, thereby eliminating the thermal neutron flux that is most sensitive to the presence of burnable poisons that are ubiquitous in modern nuclear fuels. The simulations indicate that the predicted precision of fast mode measurements is similar to what can be achieved by the present UNCL in thermal mode. For example, the

PROFILE OF POISONING CASES IN A TERTIARY CARE HOSPITAL , TELANGANA , INDIA

Directory of Open Access Journals (Sweden)

Naresh

2015-05-01

Full Text Available BACKGROUND : Poisoning with various substances is an important cause of death and disability worldwide . The types of poisons that are encountered in the emergency medicine departments encompass a wide range of substances . Apparently , geographic location , socio - demographic factors , ease of availability of poisons and many other cryptic factors contribute to the wide spectrum of substances that cause poisoning . Pesticides , drugs and chemicals are reported to be the most commo nly used poisons in India . Management of poisoning is quite challenging for the health care professionals globally . Factors such as the uncertainty in the identification of allegedly consumed poison , varied clinical features and the need for timely access to specific information for treatment , complicates poisoning management . This study was therefore conducted to explore the clinical features , management and outcomes of poisoning cases reporting to a tertiary care centre in south India . OBJECTIVE : To ident ify the spectrum of poisons and evaluate their clinical manifestations , medical management and clinical outcomes . METHODOLOGY : All cases of poisoning that were reported at a tertiary care hospital in South India for a period of 18 months from January 1 , 20 13 to June 30 , 2014 were included in this study . A data abstraction sheet was designed to document demographic details ( age and gender , poison consumed , duration of stay in the hospital , clinical features , treatment administered , need for life support and patient outcomes . RESULTS : A total of 145 poisoning cases were reported during the study period . Among them , 58 . 5% were males and 41 . 3% were females . Majority of victims were in the age group of 21 - 30 years . Intentional poisoning was observed in 86 . 2% , whereas the rest were accidental poisonings . Organophosphorus ( OP poisoning was the most common poisoning encountered in this study . It accounted for 25 . 5% of the total

Lead poisoning

Energy Technology Data Exchange (ETDEWEB)

Beijers, J A

1952-01-01

Three cases of acute lead poisoning of cattle herds via ingestion are reported, and reference is made to several other incidents of lead in both humans and animals. The quantity of lead which was found in the livers of the dead cows varied from 6.5 to 19 mg/kg, while 1160 mg/kg of lead in the liver was found for a young cow which was poisoned experimentally with 5 gms of lead acetate per day; hence, there appears to be great variability in the amounts deposited that can lead to intoxication and death. No evidence was found for a lead seam around the teeth, prophyrinuria, or basophil granules in the erythrocytes during acute or chronic lead poisoning of cattle or horses examined. Reference is made to attempts of finding the boundary line between increased lead absorption and lead intoxication in humans, and an examination of 60 laborers in an offset-printing office containing a great deal of inhalable lead (0.16 to 1.9 mg/cu m air) is reviewed. Physical deviation, basophylic granulation of erythrocytes, increased lead content of the urine, and porphyrinuria only indicate an increased absorption of lead; the use of the term intoxication is justified if, in addition, there are complaints of lack of appetite, constipation, fatigue, abdominal pain, and emaciation.

Compendium on neutron spectra in criticality accident dosimetry

International Nuclear Information System (INIS)

Ing, H.

1978-01-01

Graphical and tabulated neutron spectra are presented: from selected critical assemblies; from critical solutions; of fission neutrons through shielding; of H 2 O-moderated fission neutrons through shielding; of D 2 O-moderated fission neutrons through shielding; of fission neutrons reflected from various materials; from the D(T, 4 He)n reaction (''14 MeV'' neutrons) through shielding and of ''14 MeV'' neutrons reflected from various materials

Activation analysis by filtered neutrons. Preliminary investigation

International Nuclear Information System (INIS)

Skarnemark, G.; Rodinson, T.; Skaalberg, M.; Tokay, R.K.

1986-01-01

In order to investigate if measuring sensibility and precision by epithermal neutron activation analysis may be improved, different types of geological and biologic test samples were radiated. The test samples were enclosed in an extra filter of tungsten or sodium in order to reduce the flux of those neutrons that otherwise would induce interfering activity in the sample. The geological test samples consist of granites containing lanthanides which had been crushed in tung- sten carbide grinder. Normally such test samples show a interferins 1 87W-activity. By use of a tungsten filter the activity was reduced by up to 60%, which resulted in a considerable improvement of sensibility and precision of the measurement. The biologic test samples consisted of evaporated urine from patients treated with the cell poison cis-platinol. A reliable method to measure the platinum content has not existed so far. This method, however, enables platinum contents as low as about 0.1 ppm to be determined which is quite adequate. To sum up this preliminary study has demonstrated that activation analysis using filtered neutrons, correctly applied, is a satisfactory method of reducing interferences without complicated and time-consuming chemical separation procedures. (O.S.)

System of adjoint P1 equations for neutron moderation

International Nuclear Information System (INIS)

Martinez, Aquilino Senra; Silva, Fernando Carvalho da; Cardoso, Carlos Eduardo Santos

2000-01-01

In some applications of perturbation theory, it is necessary know the adjoint neutron flux, which is obtained by the solution of adjoint neutron diffusion equation. However, the multigroup constants used for this are weighted in only the direct neutron flux, from the solution of direct P1 equations. In this work, this procedure is questioned and the adjoint P1 equations are derived by the neutron transport equation, the reversion operators rules and analogies between direct and adjoint parameters. (author)

Epidemiology of acute poisoning in children presenting to the poisoning treatment center at Ain Shams University in Cairo, Egypt, 2009-2013.

Science.gov (United States)

Azab, Sonya M S; Hirshon, Jon Mark; Hirshon, John Mark; Hayes, Bryan D; El-Setouhy, Maged; Smith, Gordon S; Sakr, Mahmoud Lotfy; Tawfik, Hany; Klein-Schwartz, Wendy

2016-01-01

Pediatric poisonings represent a major and preventable cause of morbidity and mortality throughout the world. Epidemiologic information about poisoning among children in many lower- and middle-income countries is scarce. This study describes the epidemiology of acute poisonings in children presenting to Ain Shams University's Poisoning Treatment Center (ASU-PTC) in Cairo and determines the causative agents and characteristics of acute poisoning in several pediatric age groups. This retrospective study involved acutely poisoned patients, 0-18 years of age, who presented to the ASU-PTC between 1 January 2009 and 31 December 2013. Data were extracted from electronic records maintained by the ASU-PTC. Collected data included demographics, substance of exposure, circumstances of the poisoning, patient disposition, and outcome. During the 5-year study period, 38 470 patients meeting our criteria were treated by the ASU-PTC; 19 987 (52%) were younger than 6 years of age; 4196 (11%) were 6-12 years; and 14 287 (37%) were >12 years. Unintentional poisoning accounted for 68.5% of the ingestions, though among adolescents 84.1% of ingestions were with self-harm intent. In all age groups, the most frequent causative drugs were non-opioid analgesics, antipyretics, and antirheumatics. The most common nonpharmaceutical agents were corrosives in preschool children and pesticides in adolescents. Most patients had no/minor effects (29 174 [75.8%]); hospitalization rates were highest among adolescents. There were 119 deaths (case fatality rate of 0.3), primarily from pesticide ingestion. Poisoning in preschool children is mainly unintentional and commonly due to nonpharmaceutical agents whereas poisoning in adolescents is mainly intentional (self-harm). Pesticides, mainly organophosphorous compounds and carbamates, were the most frequent agents leading to morbidity and mortality.

Conformation and arrangement of polyelectrolytes in semi-diluted solution. A study by small angle neutrons scattering; Conformation et arrangement des polyelectrolytes en solution semi-diluee. Etude par diffusion des neutrons aux petits angles

Energy Technology Data Exchange (ETDEWEB)

Spiteri, M N

1997-03-25

Polyelectrolytes have particular physical and chemical properties and can thus be used for instance for petroleum production. Some of their microscopic properties have been studied in this work. With the particular zero average contrast technique, the small angle neutron scattering allows to directly know the form factors in semi-diluted solutions of polyelectrolytes where the chains are mixed. Another measure leads to the crystal structure. The electrostatic screen effects when salt is added in aqueous solutions of completely charged PSSNa solutions (f=1) (sodium polystyrene sulfonate) are studied. It seems that the chains take a vermiform conformation. Their persistence length varies as I{sup -1/3} (I is the ionic force). The hydrophobicity effects in partially charged PSSNa solutions (f<1) are given too. They lead to a progressive collapse of the chains when their charge rates decrease. The screen and condensation effects when the charge rate f of the PSSNa (f>f(Manning)) varies in a polar solvent (DMSO) are studied. The vermiform chains have the same persistence length (for each f) which varies as I{sup -1/4}. Lastly, the f variation effects in the case of a weakly charged hydrophilic poly-ion (f

Non-accidental dettol poisoning in a 3 day old neonate : a rare form ...

African Journals Online (AJOL)

In Nigeria, Dettol® Antiseptic Solution poisoning is an uncommon occurrence in all age groups. In a registered child specialist clinic in Kano, a three – day old neonate presented with clinical features believed initially to be due to neonatal seizures and sepsis, but which turned out to be due to non-accidental dettol® ...

Lead poisoning: The invisible disease

Science.gov (United States)

Friend, Milton

1989-01-01

Lead poisoning is an intoxication resulting from absorption of hazardous levels of lead into body tissues. Lead pellets from shot shells, when ingested, are the most common source of lead poisoning in migratory birds. Other far less common sources include lead fishing sinkers, mine wastes, paint pigments, bullets, and other lead objects that are swallowed.

webPOISONCONTROL: can poison control be automated?

Science.gov (United States)

Litovitz, Toby; Benson, Blaine E; Smolinske, Susan

2016-08-01

A free webPOISONCONTROL app allows the public to determine the appropriate triage of poison ingestions without calling poison control. If accepted and safe, this alternative expands access to reliable poison control services to those who prefer the Internet over the telephone. This study assesses feasibility, safety, and user-acceptance of automated online triage of asymptomatic, nonsuicidal poison ingestion cases. The user provides substance name, amount, age, and weight in an automated online tool or downloadable app, and is given a specific triage recommendation to stay home, go to the emergency department, or call poison control for further guidance. Safety was determined by assessing outcomes of consecutive home-triaged cases with follow-up and by confirming the correct application of algorithms. Case completion times and user perceptions of speed and ease of use were measures of user-acceptance. Of 9256 cases, 73.3% were triaged to home, 2.1% to an emergency department, and 24.5% directed to call poison control. Children younger than 6 years were involved in 75.2% of cases. Automated follow-up was done in 31.2% of home-triaged cases; 82.3% of these had no effect. No major or fatal outcomes were reported. More than 91% of survey respondents found the tool quick and easy to use. Median case completion time was 4.1 minutes. webPOISONCONTROL augments traditional poison control services by providing automated, accurate online access to case-specific triage and first aid guidance for poison ingestions. It is safe, quick, and easy to use. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Gasoline poisoning

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/002806.htm Gasoline poisoning To use the sharing features on this ... This article discusses the harmful effects from swallowing gasoline or breathing in its fumes. This article is ...

Sachet poisoning

Science.gov (United States)

... of perfumed powder or a mix of dried flowers, herbs, spices, and aromatic wood shavings (potpourri). Some ... further instructions. This is a free and confidential service. All local poison control centers in the United ...

Oxidative Metabolites of Curcumin Poison Human Type II Topoisomerases†

Science.gov (United States)

Ketron, Adam C.; Gordon, Odaine N.; Schneider, Claus; Osheroff, Neil

2013-01-01

The polyphenol curcumin is the principal flavor and color component of the spice turmeric. Beyond its culinary uses, curcumin is believed to positively impact human health and displays antioxidant, anti-inflammatory, antibacterial, and chemopreventive properties. It also is in clinical trials as an anticancer agent. In aqueous solution at physiological pH, curcumin undergoes spontaneous autoxidation that is enhanced by oxidizing agents. The reaction proceeds through a series of quinone methide and other reactive intermediates to form a final dioxygenated bicyclopentadione product. Several naturally occurring polyphenols that can form quinones have been shown to act as topoisomerase II poisons (i.e., increase levels of topoisomerase II-mediated DNA cleavage). Because several of these compounds have chemopreventive properties, we determined the effects of curcumin, its oxidative metabolites, and structurally related degradation products (vanillin, ferulic acid, and feruloylmethane), on the DNA cleavage activities of human topoisomerase IIα and IIβ. Intermediates in the curcumin oxidation pathway increased DNA scission mediated by both enzymes ~4-5–fold. In contrast, curcumin and the bicyclopentadione, as well as vanillin, ferulic acid, and feruloylmethane, had no effect on DNA cleavage. As found for other quinone-based compounds, curcumin oxidation intermediates acted as redox-dependent (as opposed to interfacial) topoisomerase II poisons. Finally, under conditions that promote oxidation, the dietary spice turmeric enhanced topoisomerase II-mediated DNA cleavage. Thus, even within the more complex spice formulation, oxidized curcumin intermediates appear to function as topoisomerase II poisons. PMID:23253398

Organophosphorus pesticide poisoning : cases and developments

NARCIS (Netherlands)

Aardema, H.; Ligtenberg, J. J. M.; Peters-Polman, O. M.; Tulleken, J. E.; Zijlstra, J. G.; Meertens, John H. J. M.

Self-poisoning with organophosphate pesticides is a major health problem world-wide. Through the inhibition of acetylcholinesterase, organophosphorus poisoning is characterised by the clinical picture of acute cholinergic crisis. Other manifestations are the intermediate neurotoxic syndrome and

Nitric Acid Poisoning: Case Report

International Nuclear Information System (INIS)

Quintero Giraldo, Maria Paulina; Quiceno Calderon, William de Jesus; Melo Arango Catalina

2011-01-01

Nitric acid (HNO 3 ) is a corrosive fluid that, when in contact with reducing agents, generates nitrogen oxides that are responsible for inhalation poisoning. We present two cases of poisoning from nitric acid gas inhalation resulting from occupational exposure. Imaging findings were similar in both cases, consistent with adult respiratory distress syndrome (ARDS): bilaterally diffuse alveolar opacities on the chest X-ray and a cobblestone pattern on computed tomography (CT).one of the patients died while the other evolved satisfactorily after treatment with n-acetyl cysteine and mechanical ventilation. The diagnosis of nitric acid poisoning was made on the basis of the history of exposure and the way in which the radiological findings evolved.

Burnable poison management in light water reactor lattices

Energy Technology Data Exchange (ETDEWEB)

Buenemann, D; Mueller, A

1970-07-01

For a better reactivity control and power flattening as well as for an increase in dynamic stability the use of burnable poisons in light water reactors has been considered. The main goals for a burnable poison management and its technological realisation are discussed. The poison is assumed to be in the form of separate poison rods or homogeneous or inhomogeneous poisoning in the fuel rods. A new concept with a central poison rod within the fuel rod is discussed. The balance-equation for the needed concentration of burnable poisons for reactivity central as well as the problems of optimization of lumped poisons are treated in connection with the fuel lattice burnup. A first approximation for the design is found. For the calculation of the microburnup of lumped poison and fuel the special code NEUTRA has been developed. The burnup-equation can be chosen either in a simplified burnup-version with 2 pseudo fission products for each fissionable isotope or with an extended system of burnup equations to be used at sophisticated calculations. These burnup equations are coupled to S{sub N}-routines optionally for cylindrical or x-y-geometry for the proper calculation of the microscopic isotope density-, flux-, and power distributions. The theoretical predictions have been checked by means of special experiments so as to determine the accuracy of the computations. Even for a relatively long burnup of the fuel the predicted values are found to be within the experimental error in the case of lumped rods containing a cadmium-alloy or boron carbide. (auth)

Comparison of poison exposure data: NHIS and TESS data.

Science.gov (United States)

Polivka, Barbara J; Elliott, Michael B; Wolowich, William R

2002-01-01

To identify age-adjusted poisoning episode rates, and poison control center contacts due to poisonings in children under 6 years old based on 1997-1999 National Health Interview Survey data; and compare findings with 1997-1999 Toxic Exposure Surveillance System data. Secondary analysis of National Health Interview Survey poisoning episode data for children 5 years and younger. Respondents were asked about poison exposures during the previous 3 months. Based on National Health Interview Survey population weighted data there were 196/10,000 poisonings to young children < 6 years. These exposures resulted primarily from harmful solid or liquid substances. A poison control center was called in 86% of exposures to children < 4 years, but only in 70% of the 4-5 year old exposures. The odds of a poison control center not being called were 3.2 times greater for 4-5 year olds (compared to < or = 3 years) and 4.5 times greater for African-American (compared with White-Americans). Comparison of National Health Interview Survey data with data in the 1997-1999 Annual Reports of the Toxic Exposure Surveillance System revealed the number of estimated exposures in the National Health Interview Survey data were approximately half those reported in the Toxic Exposure Surveillance System data. In both datasets, children 1-2 years of age had the highest percent of poisoning exposures. Using multiple datasets to explore poisoning rates in young children provides a broader perspective. Differences in findings reflect divergent data collection methods and biases inherent in each database. Although the majority of National Health Interview Survey respondents reporting contacting a poison control center for a poisoning exposure, rates are lower in specific subgroups indicating a need for targeted educational efforts.

Differences in Poisoning Mortality in the United States, 2003–2007: Epidemiology of Poisoning Deaths Classified as Unintentional, Suicide or Homicide

Science.gov (United States)

Muazzam, Sana; Swahn, Monica H.; Alamgir, Hasanat; Nasrullah, Muazzam

2012-01-01

Introduction Poisoning, specifically unintentional poisoning, is a major public health problem in the United States (U.S.). Published literature that presents epidemiology of all forms of poisoning mortalities (i.e., unintentional, suicide, homicide) together is limited. This report presents data and summarizes the evidence on poisoning mortality by demographic and geographic characteristics to describe the burden of poisoning mortality and the differences among sub-populations in the U.S. for a 5-year period. Methods Using mortality data from the Center for Disease Control and Prevention's Web-based Injury Statistics Query and Reporting System, we presented the age-specific and age-adjusted unintentional and intentional (suicide, homicide) poisoning mortality rates by sex, age, race, and state of residence for the most recent years (2003–2007) of available data. Annual percentage changes in deaths and rates were calculated, and linear regression using natural log were used for time-trend analysis. Results There were 121,367 (rate=8.18 per 100,000) unintentional poisoning deaths. Overall, the unintentional poisoning mortality rate increased by 46.9%, from 6.7 per 100,000 in 2003 to 9.8 per100.000 in 2007, with the highest mortality rate among those aged 40–59 (rate=15.36), males (rate=11.02) and whites (rate=8.68). New Mexico (rate=18.2) had the highest rate. Unintentional poisoning mortality rate increased significantly among both sexes, and all racial groups except blacks (p<0.05 time-related trend for rate). Among a total of 29,469 (rate=1.97) suicidal poisoning deaths, the rate increased by 9.9%, from 1.9 per 100,000 in 2003 to 2.1 per 100,000 in 2007, with the highest rate among those aged 40–59 (rate=3.92), males (rate=2.20) and whites (rate=2.24). Nevada (rate=3.9) had the highest rate. Mortality rate increased significantly among females and whites only (p<0.05 time-related trend for rate). There were 463 (rate=0.03) homicidal poisoning deaths and the

Experimental study of sucralfate intervention for paraquat poisoning in rats.

Science.gov (United States)

Junbo, Zhu; Yongtao, Yu; Hongbo, Li; Fenshuang, Zheng; Ruyun, Lin; Chun'ai, Yang

2017-07-01

This study explored the effects of sucralfate intervention as a novel treatment for paraquat (PQ) poisoning in Sprague-Dawley (SD) rats. After PQ poisoning, the SD rats were randomly divided into the PQ control group (treated with normal saline), the sodium bicarbonate (SB) treatment group, and the sucralfate (LTL) treatment group. Then, the rats were administered normal saline, sodium bicarbonate solution, or sucralfate suspension as an intervention by gastric lavage. At 1, 3, 6, and 10days after poisoning, the left lungs of some rats were removed to determine the lung wet/dry (W/D) weight ratio. Additionally, the serum cytokine levels were measured, and the lung and kidney tissues were pathologically examined. After treatment, the signs and symptoms of the rats were improved, the mortality rate was reduced, the W/D weight ratio of the lung was lower, the cytokine levels [transforming growth factor (TGF)-β1, interleukin (IL)-10, and tumor necrosis factor (TNF)-α] were decreased, and the pathological injuries of the lungs and kidneys were improved. Moreover, sucralfate was significantly more effective than the control (normal saline) group and the SB treatment group. The results showed that early gastrointestinal lavage with sucralfate effectively reduced the inflammatory response and lung and kidney injuries and improved the survival of the SD rats. Copyright © 2017 Elsevier B.V. All rights reserved.

Nuclear fusion and neutron processes

International Nuclear Information System (INIS)

Orlov, V.V.; Shatalov, G.E.; Sherstnev, K.E.

1984-01-01

Problems of providing development of the design of an experimental fusion reactor with necessary neutron-physical data are discussed. Isotope composition of spent fuel in the blanket of a hybride fusion reactor (HFR) is given. Neutron balance of the reactor with Li-blanket and neutron balance of the reactor with Pb-multiplier are disclosed. A simplified scheme of neutron and energy balance in the HFR blanket is given. Development and construction of the experimental power reactor is shown to become the nearest problem of the UTS program. Alongside with other complex physical and technical problems solution of this problem requires realization of a wide program of neutron-physical investigations including measurements with required accuracy of neutron cross sections, development of methodical, program and constant basis of neutron calculations and macroscopic experiments on neutron sources

An outbreak of foxglove leaf poisoning.

Science.gov (United States)

Lin, Chun-Chi; Yang, Chen-Chang; Phua, Dong-Haur; Deng, Jou-Fang; Lu, Li-Hua

2010-02-01

Comfrey (Symphytum officinale) leaves resemble those of foxglove (Digitalis purpurea) when the plant is not in bloom and, therefore, cardiac glycoside poisoning may occur when people confuse foxglove with comfrey. We report an outbreak of foxglove leaf poisoning following the use of alleged "comfrey" herbal tea. Nine patients were involved and initially presented with nausea, vomiting, diarrhea and dizziness. Significant cardiotoxicity developed later among the 3 patients who also had mild hyperkalemia. Peak serum digoxin concentration measured by immunoassay was elevated in all patients and ranged from 4.4 ng/mL to 139.5 ng/mL. Patients with severe cardiotoxicity were treated with temporary cardiac pacing. Moreover, 40-80 mg of digoxin-specific antibody therapy was given without any effect. All patients recovered uneventfully. Our report highlights the potential risk of misidentification of herbs; in this case, D. purpurea was mistaken for S. officinale. Physicians should be aware that cardiac glycoside poisoning could arise from such misidentification. Public education about the toxicity of D. purpurea poisoning may reduce the risk of misidentification and subsequent poisoning. Copyright 2010 Elsevier. Published by Elsevier B.V. All rights reserved.

Gastrolobium spp. poisoning in sheep: A case report

Science.gov (United States)

This report describes the history and investigation of a suspected plant poisoning event in Western Australia where fifteen sheep died. One of the poisoned sheep was necropsied and gross and microscopic pathology of the poisoned sheep is described. Monofluoroacetate was detected in rumen contents ...

Iodine-adsorbent poisoning: FY-82 summary report

International Nuclear Information System (INIS)

Jolley, J.G.; Casper, L.A.

1982-10-01

Along with its positive attributes as an adsorbent of radioiodine in nuclear plant air cleaning systems, silver zeolite has the disadvantage of being susceptible to poisoning. (Poisoning is defined as the reduction of efficiency in radioiodine removal.) In view of the gravimetric and infrared spectroscopy data presented, π-bonded hydrocarbons, oxygenated organics, and halocarbons appear to be probable poisons of a silver zeolite filtration system

A Narrative Review of Acute Adult Poisoning in Iran

Directory of Open Access Journals (Sweden)

Samira Alinejad

2017-07-01

Full Text Available Poisoning is a frequent cause of referral to medical emergencies and a major health problem around the world, especially in developing countries. We aimed to review the epidemiology and pattern of adult poisoning in Iran in order to facilitate the early diagnosis and management of poisoning. The pattern of poisoning is different in various parts of Iran. Pharmaceutical compounds were the most common cause of poisoning in most parts of Iran. Pesticide-related toxicities were more common in northern agricultural regions, whereas bites and stings were seen more commonly in southern Iran. Carbon monoxide poisoning was common in cities with many motor vehicles such as Tehran and in colder climates such as in northern and western regions due to inadequately vented gas appliances such as stoves and heaters. Majoon Birjandi (containing cannabis is a unique substance used in eastern Iran. Poisoning by opioids, tramadol, and pesticides (organophosphate and aluminum phosphide has remained a common hazard in Iran. Poisoning-associated morbidity and mortality rates vary by region and have changed over time due to the introduction of new drugs and chemicals. Early diagnosis and proper treatment may be lifesaving; thus, understanding the general pattern of poisoning in different regions is important.

Poison control center - Emergency number (image)

Science.gov (United States)

For a poison emergency call 1-800-222-1222 anywhere in the United States. This national hotline number will let you ... is a free and confidential service. All local poison control centers in the U.S. use this national ...

Poison Prevention

Science.gov (United States)

... Safely , for more information . If you use an e-cigarette, keep the liquid nicotine refills locked up out ... to a child. See Liquid Nicotine Used in E-Cigarettes Can Kill Children . Never place poisonous products in ...

Deodorant poisoning

Science.gov (United States)

... Poisoning and Drug Overdose . 4th ed. Philadelphia, PA: Elsevier Saunders; 2007:chap 100. Farmer B, Seger DL. ... Textbook of Critical Care . 7th ed. Philadelphia, PA: Elsevier; 2017:chap 153. Meehan TJ. Approach to the ...

[Acute lithium poisoning: epidemiology, clinical characteristics, and treatment].

Science.gov (United States)

Burguera Vion, Víctor; Montes, José Manuel; Del Rey, José Manuel; Rivera-Gorrín, Maite; Rodao, José María; Tenorio, Maite; Saiz-Ruiz, Jerónimo; Liaño, Fernando

2017-02-01

Lithium continues to be the treatment of choice for bipolar disorder. Acute lithium poisoning is a potentially serious event. We present a retrospective observational significative study of episodes of acute lithium poisoning during a 52- month period. Poisoning was defined by a blood lithium concentration of 1.5 mEq/L or higher. We analyzed treatment and epidemiologic and clinical characteristics of 70 episodes were identified (incidence density among treated patients, 1.76 per 100 patient-years). The most frequent cause of lithium poisoning was a concurrent medical condition (46%). Most poisonings were mild (74.2%), but neurologic involvement was identified in 40.3%. Electrocardiographic abnormalities were found in 8 cases. Acute renal failure, found in 23 patients (37.1%), was mild in most cases, although 11 patients required hemodialysis. We concluded that acute lithium poisoning is an uncommon complication, but risk needs to be lowered. Patients should be warned to avoid dosage errors and to take special care during concurrent illnesses and while taking other medications.

Prospects of poisoning – a multi facet study

Directory of Open Access Journals (Sweden)

Pradeep K. Mishra

2017-06-01

Full Text Available Aim of the study is to find out demographic profile, clinical characteristics and analysis of poison in clinical set up. The study carried out in Sri Aurobindo Medical College and PG Institute Indore, Madhya Pradesh. Total 75 cases of poisoning were studied for demographic profile, vitals (BP, pulse, heart rate, pupils, etc., clinical features (such as vomiting, salivation, consciousness, etc., type of poison and its analysis. Results : Poisoning was more common in cases between 15 and 25 years of age, in males than in females and in Hindu religion. Poisoning cases were predominantly from rural areas and in married people. Majority of cases were discharged after proper treatment and counseling. Altered vitals and clinical features were found in most of the cases. Organophosphate and aluminum phosphide compound were evaluated in most of the cases. Conclusions : Preventive measures should be applied through educating people, proper counseling, promoting poison information centers, and introducing separate toxicological units in hospitals.

Residence time distribution measurements in a pilot-scale poison tank using radiotracer technique.

Science.gov (United States)

Pant, H J; Goswami, Sunil; Samantray, J S; Sharma, V K; Maheshwari, N K

2015-09-01

Various types of systems are used to control the reactivity and shutting down of a nuclear reactor during emergency and routine shutdown operations. Injection of boron solution (borated water) into the core of a reactor is one of the commonly used methods during emergency operation. A pilot-scale poison tank was designed and fabricated to simulate injection of boron poison into the core of a reactor along with coolant water. In order to design a full-scale poison tank, it was desired to characterize flow of liquid from the tank. Residence time distribution (RTD) measurement and analysis was adopted to characterize the flow dynamics. Radiotracer technique was applied to measure RTD of aqueous phase in the tank using Bromine-82 as a radiotracer. RTD measurements were carried out with two different modes of operation of the tank and at different flow rates. In Mode-1, the radiotracer was instantaneously injected at the inlet and monitored at the outlet, whereas in Mode-2, the tank was filled with radiotracer and its concentration was measured at the outlet. From the measured RTD curves, mean residence times (MRTs), dead volume and fraction of liquid pumped in with time were determined. The treated RTD curves were modeled using suitable mathematical models. An axial dispersion model with high degree of backmixing was found suitable to describe flow when operated in Mode-1, whereas a tanks-in-series model with backmixing was found suitable to describe flow of the poison in the tank when operated in Mode-2. The results were utilized to scale-up and design a full-scale poison tank for a nuclear reactor. Copyright © 2015 Elsevier Ltd. All rights reserved.

Review of international solutions to NEACRP benchmark BWR lattice cell problems

International Nuclear Information System (INIS)

Halsall, M.J.

1977-12-01

This paper summarises international solutions to a set of BWR benchmark problems. The problems, posed as an activity sponsored by the Nuclear Energy Agency Committee on Reactor Physics, were as follows: 9-pin supercell with central burnable poison pin, mini-BWR with 4 pin-cells and water gaps and control rod cruciform, full 7 x 7 pin BWR lattice cell with differential U 235 enrichment, and full 8 x 8 pin BWR lattice cell with water-hole, Pu-loading, burnable poison, and homogenised cruciform control rod. Solutions have been contributed by Denmark, Japan, Sweden, Switzerland and the UK. (author)

Personality traits in persons with manganese poisoning

Energy Technology Data Exchange (ETDEWEB)

Platonov, A A

1976-10-01

Results of studies with the Minnesota Multiphasic Personality Inventory (MMPI) in 3 groups of arc welders with various degrees of manganese poisoning (22 symptom-free, 23 with functional disturbances, 55 with organic symptoms) and 50 controls were discussed. There was a close relation between the severity of the poisoning and quantitative and qualitative personality changes. Personality tests are considered a useful addition to the clinical diagnosis of chronic manganese poisoning.

Characterization of swollen structure of high-density polyelectrolyte brushes in salt solution by neutron reflectivity

Energy Technology Data Exchange (ETDEWEB)

Kobayashi, Motoyasu; Takahara, Atsushi [Institute for Materials Chemistry and Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan); Terayama, Yuki [Graduate School of Engineering, Kyushu University (Japan); Hino, Masahiro [Reactor Research Institute, Kyoto University (Japan); Ishihara, Kazuhiko, E-mail: takahara@cstf.kyushu-u.ac.j [Graduate School of Engineering, University of Tokyo (Japan)

2009-08-01

Zwitterionic and cationic polyelectrolyte brushes on quartz substrate were prepared by surface-initiated atom transfer radical polymerization of 2-(methacryloyloxy)ethyl phosphorylcholine (MPC) and 2-(methacryloyloxy)ethyltrimethylammonium chloride (METAC), respectively. The effects of ionic strength on brush structure and surface properties of densely grafted polyelectrolyte brushes were analysed by neutron reflectivity (NR) measurements. NR at poly(METAC)/D{sub 2}O and poly(MPC)/D{sub 2}O interface revealed that the grafted polymer chains were fairly extended from the substrate surface, while the thickness reduction of poly(METAC) brush was observed in 5.6 M NaCl/D{sub 2}O solution due to the screening of the repulsive interaction between polycations by hydrated salt ions. Interestingly, no structural change was observed in poly(MPC) brush even in a salt solution probably due to the unique interaction properties of phosphorylcholine units.

Hemlock (Conium Maculatum) Poisoning In A Child.

Science.gov (United States)

Konca, Capan; Kahramaner, Zelal; Bosnak, Mehmet; Kocamaz, Halil

2014-03-01

Poison hemlock (Conium maculatum) is a plant that is poisonous for humans and animals. Accidental ingestion of the plant may result in central nervous system depression, respiratory failure, acute rhabdomyolysis, acute renal failure and even death. The main treatment of hemlock poisoning is supportive care. The case of a 6-year-old girl who was admitted to the emergency department with complaints of burning sensation in mouth, hypersalivation, tremor in hands and ataxia after ingestion of poison hemlock is presented here with clinical and laboratory features. In this case, we aim to report that accidental ingestion of plants resembling vegetables that are consumed daily can lead to serious complications and even death.

Hemlock (Conium Maculatum Poisoning In A Child

Directory of Open Access Journals (Sweden)

Capan KONCA

2014-03-01

Full Text Available Poison hemlock (Conium maculatum is a plant that is poisonous for humans and animals. Accidental ingestion of the plant may result in central nervous system depression, respiratory failure, acute rhabdomyolysis, acute renal failure and even death. The main treatment of hemlock poisoning is supportive care. The case of a 6-year-old girl who was admitted to the emergency department with complaints of burning sensation in mouth, hypersalivation, tremor in hands and ataxia after ingestion of poison hemlock is presented here with clinical and laboratory features. In this case, we aim to report that accidental ingestion of plants resembling vegetables that are consumed daily can lead to serious complications and even death.

Diagnosis & Treatment of Poisoning by Pesticides.

Science.gov (United States)

Environmental Protection Agency, Washington, DC. Office of Pesticide Programs.

This report succinctly discusses the steps necessary to diagnose and treat poisoning from pesticides, especially organophosphates, carbamates and chlorinated hydrocarbons. Immediate and continuing steps in the care of poisoning victims are outlined with supportive information on where to locate emergency assistance. (CS)

Real time neutron flux monitoring using Rh self powered neutron detector

Energy Technology Data Exchange (ETDEWEB)

Juna, Byung Jin; Lee, Byung Chul; Park, Sang Jun; Jung, Hoan Sung [KAERI, Daejeon (Korea, Republic of)

2012-10-15

Rhodium (Rh) self powered neutron detectors (SPNDs) are widely used for on line monitoring of local neutron flux. Its signal is slower than the actual variation of neutron flux owing to a delayed {beta} decay of the Rh activation product, but real time monitoring is possible by solving equations between the neutron reaction rate in the detector and its signal. While the measuring system is highly reliable, the accuracy depends on the method solving the equations and accuracy of the parameters in the equations. The uncertain parameters are the contribution of gamma rays to the signal, and the branching ratios of Rh 104 and Rh 104m after the neutron absorption of Rh 103. Real time neutron flux monitoring using Rh SPNDs has been quite successful for neutron transmutation doping (NTD) at HANARO. We revisited the initial data used for the verification of a real time monitoring system, to refine algorithm for a better solution and to check the parameters for correctness. As a result, we suggest an effective way to determine the prompt parameter.

Real time neutron flux monitoring using Rh self powered neutron detector

International Nuclear Information System (INIS)

Juna, Byung Jin; Lee, Byung Chul; Park, Sang Jun; Jung, Hoan Sung

2012-01-01

Rhodium (Rh) self powered neutron detectors (SPNDs) are widely used for on line monitoring of local neutron flux. Its signal is slower than the actual variation of neutron flux owing to a delayed β decay of the Rh activation product, but real time monitoring is possible by solving equations between the neutron reaction rate in the detector and its signal. While the measuring system is highly reliable, the accuracy depends on the method solving the equations and accuracy of the parameters in the equations. The uncertain parameters are the contribution of gamma rays to the signal, and the branching ratios of Rh 104 and Rh 104m after the neutron absorption of Rh 103. Real time neutron flux monitoring using Rh SPNDs has been quite successful for neutron transmutation doping (NTD) at HANARO. We revisited the initial data used for the verification of a real time monitoring system, to refine algorithm for a better solution and to check the parameters for correctness. As a result, we suggest an effective way to determine the prompt parameter

Vital Signs-Alcohol Poisoning Deaths

Centers for Disease Control (CDC) Podcasts

2015-01-06

This podcast is based on the January 2015 CDC Vital Signs report. In the United States, an average of six people die every day from alcohol poisoning. Learn what you can do to prevent binge drinking and alcohol poisoning.  Created: 1/6/2015 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 1/6/2015.

Direct observation of solute segregation to voids in a fast-neutron irradiated (Mo/1.0 at. % Ti alloy

International Nuclear Information System (INIS)

Wagner, A.; Seidman, D.N.

1978-11-01

The atom-probe field-ion microscope was used to study segregation effects to voids in a Mo--Ti alloy which had been irradiated with fast neutrons. The Ti does not segregate significantly to voids, concentration of Ti in solid solution and the spacial distribution of Ti was not affected by irradiation, carbon was not detected, resolution of TiC or MoC precipitates did not occur

The neutron's Dirac-equation: Its rigorous solution at slab-like magnetic fields, non-relativistic approximation, energy spectra and statistical characteristics

International Nuclear Information System (INIS)

Zhang Yongde.

1987-03-01

In this paper, the neutron Dirac-equation is presented. After decoupling it into two equations of the simple spinors, the rigorous solution of this equation is obtained in the case of slab-like uniform magnetic fields at perpendicular incidence. At non-relativistic approximation and first order approximation of weak field (NRWFA), our results have included all results that have been obtained in references for this case up to now. The corresponding transformations of the neutron's spin vectors are given. The single particle spectrum and its approximate expression are obtained. The characteristics of quantum statistics with the approximate expression of energy spectrum are studied. (author). 15 refs

Do poison center triage guidelines affect healthcare facility referrals?

Science.gov (United States)

Benson, B E; Smith, C A; McKinney, P E; Litovitz, T L; Tandberg, W D

2001-01-01

The purpose of this study was to determine the extent to which poison center triage guidelines influence healthcare facility referral rates for acute, unintentional acetaminophen-only poisoning and acute, unintentional adult formulation iron poisoning. Managers of US poison centers were interviewed by telephone to determine their center's triage threshold value (mg/kg) for acute iron and acute acetaminophen poisoning in 1997. Triage threshold values and healthcare facility referral rates were fit to a univariate logistic regression model for acetaminophen and iron using maximum likelihood estimation. Triage threshold values ranged from 120-201 mg/kg (acetaminophen) and 16-61 mg/kg (iron). Referral rates ranged from 3.1% to 24% (acetaminophen) and 3.7% to 46.7% (iron). There was a statistically significant inverse relationship between the triage value and the referral rate for acetaminophen (p variability in poison center triage values and referral rates for iron and acetaminophen poisoning. Guidelines can account for a meaningful proportion of referral variation. Their influence appears to be substance dependent. These data suggest that efforts to determine and utilize the highest, safe, triage threshold value could substantially decrease healthcare costs for poisonings as long as patient medical outcomes are not compromised.

Interpersonal Problem-Solving Deficits in Self-Poisoning Patients.

Science.gov (United States)

McLeavey, Breda C.; And Others

1987-01-01

Compared self-poisoning patients with psychiatric patients and nonpatient controls on problem-solving skills and locus of control. The psychiatric and self-poisoning groups showed deficits on interpersonal problem solving compared with nonpatient controls. The self-poisoning group performed below or at the level of the psychiatric group. Locus of…

Differences in Poisoning Mortality in the United States, 2003–2007: Epidemiology of Poisoning Deaths Classified as Unintentional, Suicide or Homicide

Directory of Open Access Journals (Sweden)

Sana Muazzam

2012-08-01

Full Text Available Introduction: Poisoning, specifically unintentional poisoning, is a major public health problem in the United States (U.S.. Published literature that presents epidemiology of all forms of poisoning mortalities (i.e., unintentional, suicide, homicide together is limited. This report presents data and summarizes the evidence on poisoning mortality by demographic and geographic characteristics to describe the burden of poisoning mortality and the differences among sub-populations in the U.S. for a 5-year period.Methods: Using mortality data from the Center for Disease Control and Prevention’s Web-based Injury Statistics Query and Reporting System, we presented the age-specific and age-adjusted unintentional and intentional (suicide, homicide poisoning mortality rates by sex, age, race, and state of residence for the most recent years (2003–2007 of available data. Annual percentage changes in deaths and rates were calculated, and linear regression using natural log were used for time-trend analysis.Results: There were 121,367 (rate¼8.18 per 100,000 unintentional poisoning deaths. Overall, the unintentional poisoning mortality rate increased by 46.9%, from 6.7 per 100,000 in 2003 to 9.8 per100.000 in 2007, with the highest mortality rate among those aged 40–59 (rate¼15.36, males(rate¼11.02 and whites (rate¼8.68. New Mexico (rate¼18.2 had the highest rate. Unintentional poisoning mortality rate increased significantly among both sexes, and all racial groups except blacks (p,0.05 time-related trend for rate. Among a total of 29,469 (rate¼1.97 suicidal poisoning deaths, the rate increased by 9.9%, from 1.9 per 100,000 in 2003 to 2.1 per 100,000 in 2007, with the highest rate among those aged 40–59 (rate¼3.92, males (rate¼2.20 and whites (rate¼2.24. Nevada(rate¼3.9 had the highest rate. Mortality rate increased significantly among females and whites only (p,0.05 time-related trend for rate. There were 463 (rate¼0.03 homicidal poisoning

Hospitalized poisonings after renal transplantation in the United States

Directory of Open Access Journals (Sweden)

Viola Rebecca A

2002-11-01

Full Text Available Abstract Background The national incidence of and risk factors for hospitalized poisonings in renal transplant recipients has not been reported. Methods Historical cohort study of 39,628 renal transplant recipients in the United States Renal Data System between 1 July 1994 and 30 June 1998. Associations with time to hospitalizations for a primary diagnosis of poisonings (ICD-9 codes 960.x-989.x within three years after renal transplant were assessed by Cox Regression. Results The incidence of hospitalized poisonings was 2.3 patients per 1000 person years. The most frequent causes of poisonings were immunosuppressive agents (25.3%, analgesics/antipyretics (14.1%, psychotropic agents (10.0%, and insulin/antidiabetic agents (7.1%. In Cox Regression analysis, low body mass index (BMI, 28.3 kg/m2, adjusted hazard ratio (AHR, 3.02, 95% CI, 1.45–6.28, and allograft rejection, AHR 1.83, 95% CI, 1.15–2.89, were the only factors independently associated with hospitalized poisonings. Hospitalized poisonings were independently associated with increased mortality (AHR, 1.54, 95% CI 1.22–1.92, p = 0.002. Conclusions Hospitalized poisonings were associated with increased mortality after renal transplantation. However, almost all reported poisonings in renal transplant recipients were due to the use of prescribed medications. Allograft rejection and low BMI were the only independent risk factors for poisonings identified in this population.

Aggressive electrolyte poisons and multifunctional fluids comprised of diols and diamines for emergency shutdown of lithium-ion batteries

Science.gov (United States)

Noelle, Daniel J.; Shi, Yang; Wang, Meng; Le, Anh V.; Qiao, Yu

2018-04-01

Electrolyte poisons comprised of diols and diamines are investigated for the intended function of exacerbating internal resistance in lithium-ion batteries upon short circuit failure, to quickly arrest uncontrolled joule heat generation in the earliest stages. The competing dynamics of powerful short circuit currents and electrolyte poisoning interactions are evaluated via simultaneous nail penetration and poison injection of LIR2450 format LiCoO2/graphite 120 mAh coin cells. To forcibly increase electrolyte impedance, diols serve to hinder charge-carrying ion mobility by raising solution viscosity, while diamines disrupt solvent permittivity by rapidly polymerizing the ethylene carbonate solvent. Diamines demonstrate great potency, and are suitable for integration into battery cells within chemically-inert, breakable containers, rigged for release upon mechanical activation. Mixtures of 1,2-ethanediol and 1,2-ethanediamine show synergistic poisoning effects, decreasing peak temperature accrued by 70% when introduced simultaneously upon nail penetration. With the innate presence and abundance of diols and diamines in electric vehicle heat exchangers, they may be employed for multifunctional applications.

Dosimetry techniques of thermal neutrons and {gamma} radiation in reactor cores; Techniques de dosimetrie des neutrons thermiques et du rayonnement {gamma} dans les piles

Energy Technology Data Exchange (ETDEWEB)

Sutton, J; Draganic, I; Hering, H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

Chemical studies under radiation done in the reactor cores require to be followed by dosimetry. When the irradiations are done in the reflector, one can limit to the measure of the {gamma} and the neutron radiation. For the dosimetry of the {gamma} radiation, a dosimeter of ferrous sulfate is convenient until doses of about 10{sup 6} rep. The use of aired oxalic acid solutions permits to reach 10{sup 7} rep. The dosimetry of thermal neutrons has been made with solutions of cobalt sulphate or paper filter impregnated with this salt. The total chemical effect of the {gamma} and of the slow neutrons radiation is obtained with solutions of ferrous sulfate added with lithium sulphate. (M.B.) [French] Les etudes de chimie sous radiation faites dans les piles exigent d'etre suivies par dosimetrie. Lorsque les irradiations sont effectues dans le reflecteur, on peut se limiter a doser le rayonnement {gamma} et les neutrons. Pour la dosimetrie du rayonnement {gamma}, un dosimetre a sulfate ferreux convient jusqu'a des doses d'environ 10{sup 6} rep. L'emploi de solutions aerees d'acide oxalique permet d'atteindre 10{sup 7} rep. La dosimetrie des neutrons thermiques a ete faite avec des solutions de sulfate de cotalt ou du papier filtre impregne de ce sel. L'effet chimique total du rayonnement {gamma} et des neutrons lents est obtenu avec des solutions de sulfate ferreux additionne de sulfate de lithium. (M.B.)

Alkaloid-Containing Plants Poisonous to Cattle and Horses in Europe.

Science.gov (United States)

Cortinovis, Cristina; Caloni, Francesca

2015-12-08

Alkaloids, nitrogen-containing secondary plant metabolites, are of major interest to veterinary toxicology because of their occurrence in plant species commonly involved in animal poisoning. Based on epidemiological data, the poisoning of cattle and horses by alkaloid-containing plants is a relatively common occurrence in Europe. Poisoning may occur when the plants contaminate hay or silage or when forage alternatives are unavailable. Cattle and horses are particularly at risk of poisoning by Colchicum autumnale (meadow saffron), Conium maculatum (poison hemlock), Datura stramonium (jimson weed), Equisetum palustre (marsh horsetail), Senecio spp. (ragwort and groundsel) and Taxus baccata (European yew). This review of poisonous alkaloid-containing plants describes the distribution of these plants, conditions under which poisoning occurs, active toxic principles involved and subsequent clinical signs observed.

Finding of CT and clinical in paraquat poisoning pulmonary injury

International Nuclear Information System (INIS)

He Zaifang; Li Hongbing; Cheng Shoulin; Li Qixiang; Huang Zhen; Zeng Jianguo

2012-01-01