Nonlinear beam clean-up using resonantly enhanced sum-frequency mixing
DEFF Research Database (Denmark)
Karamehmedovic, Emir; Pedersen, Christian; Jensen, Ole Bjarlin
2009-01-01
We investigate the possibility of improving the beam quality and obtaining high conversion efficiency in nonlinear sum-frequency generation. A 765 nm beam from an external cavity tapered diode laser is single-passed through a nonlinear crystal situated in the high intracavity field of a 1342 nm N......:YVO4 laser, generating a SFG beam at 488 nm. The ECDL have MH^2=1.9 and MV^2=2.4 and the solid-state laser has M^2...
E-beam radiolysis for oil spill clean up
International Nuclear Information System (INIS)
Patterson, E.L.; Jackson, N.B.; Thornberg, S.M.; Samlin, G.E.
1992-12-01
This paper describes preliminary experiments to investigate electron-beam radiolysis of model compounds appropriate for crude oil spills on water or soil. Since no previous work in this area is known to exist, the rate of destruction of such concentrated organic materials in aqueous media is not known. The experiments conducted here were designed to provide preliminary estimates of the destruction rate and the estimated costs. Samples of model compounds were irradiated to dose levels up to 700 Mrad (H 2 0) and the change in chemical composition was determined by mass spectrometry/gas chromatography and Fourier transform infrared spectroscopy. It was found that a dose of 700 Mrads reduced the liquid volume of the model compound by 60% and that the major effect of irradiation was the formation of long chain alkanes and dimethyl and ethyl benzenes. Under certain conditions a solid polymer was found to form. When alcohol was present in the model compound, additional products included small quantities of ethane diodic acid, butanol, butanediol, and various other alcohols. Further research is recommended to obtain a better analysis of the products, better values for the destruction rates, and better understanding of dose rate effects
Westra, H.J.R.
2012-01-01
In this Thesis, nonlinear dynamics and nonlinear interactions are studied from a micromechanical point of view. Single and doubly clamped beams are used as model systems where nonlinearity plays an important role. The nonlinearity also gives rise to rich dynamic behavior with phenomena like
Stationary nonlinear Airy beams
International Nuclear Information System (INIS)
Lotti, A.; Faccio, D.; Couairon, A.; Papazoglou, D. G.; Panagiotopoulos, P.; Tzortzakis, S.; Abdollahpour, D.
2011-01-01
We demonstrate the existence of an additional class of stationary accelerating Airy wave forms that exist in the presence of third-order (Kerr) nonlinearity and nonlinear losses. Numerical simulations and experiments, in agreement with the analytical model, highlight how these stationary solutions sustain the nonlinear evolution of Airy beams. The generic nature of the Airy solution allows extension of these results to other settings, and a variety of applications are suggested.
Nonlinear beam expander for ESNIT
International Nuclear Information System (INIS)
Rusthoi, D.P.; Blind, B.; Garnett, R.W.; Hanna, D.S.; Jason, A.J.; Kraus, R.H. Jr.; Neri, F.
1994-01-01
We describe the design of a beam-redistribution and expansion system for the Japanese Atomic Energy Research Institute (JAERI) Energy Selective Neutron Irradiation Test Facility (ESNIT). The system tailors the beam exiting a deuteron accelerator at energies from 20 to 35 MeV for deposition on a lithium neutron-production target. A uniform beam-intensity distribution in a well-defined irradiation area is inquired at the target and is achieved by the use of nonlinear elements. The design of the high-energy beam transport (HEBT) for ESNIT includes a 90 degree achromatic bend, a matching section with an energy-compacting cavity, a nonlinear beam expander, a target imager, a shielding dipole, and an rf-cavity system to add energy spread to the beam before it impinges on the target. The system meets performance requirements at multiple energies and currents, and for different spot sizes on target
Cleaning Up Our Drinking Water
International Nuclear Information System (INIS)
Manke, Kristin L.
2007-01-01
Imagine drinking water that you wring out of the sponge you've just used to wash your car. This is what is happening around the world. Rain and snow pass through soil polluted with pesticides, poisonous metals and radionuclides into the underground lakes and streams that supply our drinking water. 'We need to understand this natural system better to protect our groundwater and, by extension, our drinking water,' said Pacific Northwest National Laboratory's Applied Geology and Geochemistry Group Manager, Wayne Martin. Biologists, statisticians, hydrologists, geochemists, geologists and computer scientists at PNNL work together to clean up contaminated soils and groundwater. The teams begin by looking at the complexities of the whole environment, not just the soil or just the groundwater. PNNL researchers also perform work for private industries under a unique use agreement between the Department of Energy and Battelle, which operates the laboratory for DOE. This research leads to new remediation methods and technologies to tackle problems ranging from arsenic at old fertilizer plants to uranium at former nuclear sites. Our results help regulators, policy makers and the public make critical decisions on complex environmental issues
Stochastic nonlinear beam equations
Czech Academy of Sciences Publication Activity Database
Brzezniak, Z.; Maslowski, Bohdan; Seidler, Jan
2005-01-01
Roč. 132, č. 1 (2005), s. 119-149 ISSN 0178-8051 R&D Projects: GA ČR(CZ) GA201/01/1197 Institutional research plan: CEZ:AV0Z10190503 Keywords : stochastic beam equation * stability Subject RIV: BA - General Mathematics Impact factor: 0.896, year: 2005
International Nuclear Information System (INIS)
CONNELL, C.W.
2005-01-01
The Hanford Federal Facility Agreement and Consent Order, known as the ''Tri-Party Agreement'' (TPA), is a legally binding agreement among the US Department of Energy (DOE), The Washington State Department of Ecology, and the US Environmental Protection Agency (EPA) for cleaning up the Hanford Site. Established in the 1940s to produce material for nuclear weapons as part of the Manhattan Project, Hanford is often referred to as the world's large environmental cleanup project. The Site covers more than 580 square miles in a relatively remote region of southeastern Washington state in the US. The production of nuclear materials at Hanford has left a legacy of tremendous proportions in terms of hazardous and radioactive waste. From a waste-management point of view, the task is enormous: 1700 waste sites; 450 billion gallons of liquid waste; 70 billion gallons of contaminated groundwater; 53 million gallons of tank waste; 9 reactors; 5 million cubic yards of contaminated soil; 22 thousand drums of mixed waste; 2.3 tons of spent nuclear fuel; and 17.8 metric tons of plutonium-bearing material and this is just a partial listing. The agreement requires that DOE provide the results of analytical laboratory and non-laboratory tests/readings to the lead regulatory agency to help guide then in making decisions. The agreement also calls for each signatory to preserve--for at least ten years after the Agreement has ended--all of the records in it, or its contractors, possession related to sampling, analysis, investigations, and monitoring conducted. The Action Plan that supports the TPA requires that Ecology and EPA have access to all data that is relevant to work performed, or to be performed, under the Agreement. Further, the Action Plan specifies two additional requirements: (1) that EPA, Ecology and their respective contractor staffs have access to all the information electronically, and (2) that the databases are accessible to, and used by, all personnel doing TPA
International Nuclear Information System (INIS)
Tanaka, Koji; Egashira, Yasuo; Shimada, Fumie; Igarashi, Noboru.
1983-01-01
Purpose: To save a low temperature reactor water clean-up system indispensable so far and significantly simplify the system by carrying out the reactor water clean-up solely in a high temperature reactor water clean-up system. Constitution: The reactor water clean-up device comprises a high temperature clean-up pump and a high temperature adsorption device for inorganic adsorbents. The high temperature adsorption device is filled with amphoteric ion adsorbing inorganic adsorbents, or amphoteric ion adsorbing inorganic adsorbents and anionic adsorbing inorganic adsorbents. The reactor water clean-up device introduces reactor water by the high temperature clean-up pump through a recycling system to the high temperature adsorption device for inorganic adsorbents. Since cations such as cobalt ions and anions such as chlorine ions in the reactor water are simultaneously removed in the device, a low temperature reactor water clean-up system which has been indispensable so far can be saved to realize the significant simplification for the entire system. (Seki, T.)
International Nuclear Information System (INIS)
Wallace, Paula
2012-01-01
Full text: The project at Biodiesel Producers Limited in Victoria involved remediation of a wastewater treatment process containing a large covered anaerobic lagoon, an aerobic sequencing batch reactor (SBR) and a series of downstream open ponds. The pond downstream of the SBR was heavily loaded with a thick hard grease cap. The CAL was believed to have a metre-plus grease cap and the SBR had developed a thick foam cap that prevented aeration and mixing. Environmental Biotech was called in to assist with bioremediation using its Grease Eradication System bacteria cultures, with the aim of reducing the fats, oil and grease in the CAL discharge to less than 150 milligrams per litre, eliminating the stable fat foam in the SBR to allow the denitrification sequencing program to be reinstated and to clean up the hard fat layer from the surfaces of the comany's open ponds. The inflow to the CAL was designed for a flow of 210kL per day with a loading of 6900mg/L biochemical oxygen demand and FOG of 425mg/L. The actual load, as measured by Environmental Biotech, was 100kL with 20,000mg/L BOD and 1800mg/L (180kg) FOG. The CAL had been in use for more than two years, generating methane but assumed to be working well in the breakdown of chemical oxygen demand and FOG. In December 2009 the quality of the effluent began to decrease, overloading the SBR with FOG. It caused the formation of dense foam on aeration and mixing. The foam would not break down despite a variety of methods being employed and would overflow from the walls of the SBR. “Due to the foaming issue the SBR became a large holding tank for the fat and because of the reduced mixing, the solids were settling on the bottom of the tank,” Environmental Biotech project manager and franshisee Craig Barr said. “We were brought in to start work inApril 2010 and initially we slug dosed the CAL with 400 litres of GES bacteria in addition to a constant metered dosing rate of 400 litres per fortnight with the
Nonlinear diffraction from a virtual beam
DEFF Research Database (Denmark)
Saltiel, Solomon M.; Neshev, Dragomir N.; Krolikowski, Wieslaw
2010-01-01
We observe experimentally a novel type of nonlinear diffraction in the process of two-wave mixing on a nonlinear quadratic grating.We demonstrate that when the nonlinear grating is illuminated simultaneously by two noncollinear beams, a second-harmonic diffraction pattern is generated by a virtual...... beam propagating along the bisector of the two pump beams. The observed iffraction phenomena is a purely nonlinear effect that has no analogue in linear diffraction...
Nonlinear optical beam manipulation, beam combining, and atmospheric propagation
International Nuclear Information System (INIS)
Fischer, R.A.
1988-01-01
These proceedings collect papers on optics: Topics include: diffraction properties of laser speckle, coherent beam combination by plasma modes, nonlinear responses, deformable mirrors, imaging radiometers, electron beam propagation in inhomogeneous media, and stability of laser beams in a structured environment
Coolant clean-up and recycle systems
International Nuclear Information System (INIS)
Ito, Takao.
1979-01-01
Purpose: To increase the service life of mechanical seals in a shaft sealing device, eliminate leakages and improve the safety by providing a recycle pump for feeding coolants to a coolant clean-up device upon reactor shut-down and adapting the pump treat only low temperature and low pressure coolants. Constitution: The system is adapted to partially take out coolants from the pipeways of a recycling pump upon normal operation and feed them to a clean-up device. Upon reactor shut-down, the recycle pump is stopped and coolants are extracted by the recycle pump for shut-down into the clean-up device. Since the coolants are not fed to the clean-up device by the recycle pump during normal operation as conducted so far, high temperature and high pressure coolants are not directly fed to the recycle pump, thereby enabling to avoid mechanical problems in the pump. (Kamimura, M.)
Nonlinear transport of accelerator beam phase space
International Nuclear Information System (INIS)
Xie Xi; Xia Jiawen
1995-01-01
Based on the any order analytical solution of accelerator beam dynamics, the general theory for nonlinear transport of accelerator beam phase space is developed by inverse transformation method. The method is general by itself, and hence can also be applied to the nonlinear transport of various dynamic systems in physics, chemistry and biology
Nonlinear beam dynamics experimental program at SPEAR
International Nuclear Information System (INIS)
Tran, P.; Pellegrini, C.; Cornacchia, M.; Lee, M.; Corbett, W.
1995-01-01
Since nonlinear effects can impose strict performance limitations on modern colliders and storage rings, future performance improvements depend on further understanding of nonlinear beam dynamics. Experimental studies of nonlinear beam motion in three-dimensional space have begun in SPEAR using turn-by-turn transverse and longitudinal phase-space monitors. This paper presents preliminary results from an on-going experiment in SPEAR
Boundary controllability for a nonlinear beam equation
Directory of Open Access Journals (Sweden)
Xiao-Min Cao
2015-09-01
Full Text Available This article concerns a nonlinear system modeling the bending vibrations of a nonlinear beam of length $L>0$. First, we derive the existence of long time solutions near an equilibrium. Then we prove that the nonlinear beam is locally exact controllable around the equilibrium in $H^4(0,L$ and with control functions in $H^2(0,T$. The approach we used are open mapping theorem, local controllability established by linearization, and the induction.
Radioactive Waste and Clean-up Division
International Nuclear Information System (INIS)
Collard, G.
2001-01-01
The main objectives of the Radioactive Waste and Clean-up division of SCK-CEN are outlined. The division's programme consists of research, development and demonstration projects and aims to contribute to the objectives of Agenda 21 on sustainable development in the field of radioactive waste and rehabilitation of radioactively contaminated sites
Dynamic beam cleaning by a nonlinear resonance
Energy Technology Data Exchange (ETDEWEB)
Chao, A W; Month, M [Brookhaven National Lab., Upton, N.Y. (USA)
1976-03-15
The general framework for the dynamic cleaning of a stored proton beam by passing the beam through a nonlinear resonance is developed. The limitations and advantages of this technique are discussed. The method is contrasted with physical beam scraping, which is currently in use at the CERN ISR.
Clean-up of a radioactive spill
International Nuclear Information System (INIS)
Fish, W.
1987-01-01
Bikini Atoll in the Marshall Islands of the South Pacific was extensively contaminated with radionuclides deposited by thermonuclear weapons testing in the 1940s and 1950s. In recent years, the U.S. government has attempted to restore the habitability of the islands by cleaning up the remaining radioactive material. Although the island no longer presents an acute radiation risk to inhabitants, plants growing on the island concentrate cesium-137 from the soil, presenting an unacceptable risk to the future population. The behavior of Cs-137 has proved to be an intractable problem that has major implications for the risks associated with transporting and processing high-level nuclear wastes in the U.S. Various proposed soil treatment strategies for Bikini are discussed, including ion-exchange treatments and competing-ion strategies. No fully satisfactory treatment currently exists and the problems and prospects of cleaning up after a major nuclear waste spill are presented
Alternative Fuels Data Center: Phoenix Cleans Up with Natural Gas
Phoenix Cleans Up with Natural Gas to someone by E-mail Share Alternative Fuels Data Center : Phoenix Cleans Up with Natural Gas on Facebook Tweet about Alternative Fuels Data Center: Phoenix Cleans Up with Natural Gas on Twitter Bookmark Alternative Fuels Data Center: Phoenix Cleans Up with Natural
Experimental studies of nonlinear beam dynamics
International Nuclear Information System (INIS)
Caussyn, D.D.; Ball, M.; Brabson, B.; Collins, J.; Curtis, S.A.; Derenchuck, V.; DuPlantis, D.; East, G.; Ellison, M.; Ellison, T.; Friesel, D.; Hamilton, B.; Jones, W.P.; Lamble, W.; Lee, S.Y.; Li, D.; Minty, M.G.; Sloan, T.; Xu, G.; Chao, A.W.; Ng, K.Y.; Tepikian, S.
1992-01-01
The nonlinear beam dynamics of transverse betatron oscillations were studied experimentally at the Indiana University Cyclotron Facility cooler ring. Motion in one dimension was measured for betatron tunes near the third, fourth, fifth, and seventh integer resonances. This motion is described by coupling between the transverse modes of motion and nonlinear field errors. The Hamiltonian for nonlinear particle motion near the third- and fourth-integer-resonance conditions has been deduced
Beam Stability and Nonlinear Dynamics. Proceedings
International Nuclear Information System (INIS)
Parsa, Z.
1997-01-01
These proceedings represent papers presented at the Beam Stability and Nonlinear Dynamics symposium held in Santa Barbara in December 1996. The symposium was sponsored by the National Science Foundation as part of the United States long term accelerator research. The focus of this symposium was on nonlinear dynamics and beam stability. The topics included single-particle and many-particle dynamics, and stability in large circular accelerators such as the Large Hadron Collider(LHC). Other subjects covered were spin dynamics, nonlinear aberration correction, collective effects in the LHC, sawtooth instability and Landau damping in the presence of strong nonlinearity. There were presentations concerning plasma physics including the effect of beam echo. There are 17 papers altogether in these proceedings and 8 of them have been abstracted for the Energy Science and Technology database
Coolant clean up system in nuclear reactor
International Nuclear Information System (INIS)
Tajima, Fumio; Iwami, Hiroshi.
1981-01-01
Purpose: To decrease the amount of main steams and improve the plant heat efficiency by the use of condensated water as coolants for not-regenerative heat exchangers in a coolant clean up system of a nuclear reactor. Constitution: In a coolant clean up system of a nuclear reactor, a portion of condensates is transferred to the shell of a non-regenerative heat exchanger by way of a condensate pump for non-regenerative heat exchanger through a branched pipeway provided to the outlet of a condensate desalter for using the condensates as the coolants for the shell of the heat exchanger and the condensates are then returned to the inlet of a feedwater heater after the heat exchange. The branched flow rate of the condensates is controlled by the flow rate control valve mounted in the pipeway. Condensates passed through the heat exchanger and the condensates not passed through the heat exchanger are mixed and heated in a heater and then fed to the nuclear reactor. In a case where no feedwater is necessary to the nuclear reactor such as upon shutdown of the reactor, the condensates are returned by way of feedwater bypass pipeway to the condensator. By the use of the condensates as the coolants for the heat exchanger, the main steam loss can be decreased and the thermal load for the auxiliary coolant facility can be reduced. (Kawakami, Y.)
Radioactive Waste and Clean-up: Introduction
International Nuclear Information System (INIS)
Collard, G.
2007-01-01
The primary mission of the Radioactive Waste and Clean-up division is to propose, to develop and to evaluate solutions for a safe, acceptable and sustainable management of radioactive waste. The Radioactive Waste and Clean-up division programme consists in research, studies, development and demonstration aiming to realise the objective of Agenda 21 on sustainable development in the field of radioactive waste and rehabilitation on radioactively contaminated sites. Indeed, it participates in the realisation of an objective which is to ensure that radioactive wastes are safely managed, transported, stored and disposed of, with a view to protecting human health and the environment, within a wider framework of an interactive and integrated approach to radioactive waste management and safety. We believe that nuclear energy will be necessary for the sustainable development of mankind in the 21st century, but we well understand that it would not be maintained if it is not proven that within benefits of nuclear energy a better protection of the environment is included. Although the current waste management practices are both technically and from the environmental point of view adequate, efforts in relation of future power production and waste management technologies should be put on waste minimisation. Therefore, the new and innovative reactors, fuel cycle and waste management processes and installations should be designed so that the waste generation can be kept in minimum. In addition to the design, the installations should be operated so as to create less waste; consideration should be given e.g. to keeping water chemistry clean and other quality factors. SCK-CEN in general and the Radioactive Waste and Clean-up division in particular are present in international groups preparing the development of innovative nuclear reactors, as Generation 4 and INPRO. Because performance assessments are often black boxes for the public, demonstration is needed for the acceptation of
International Nuclear Information System (INIS)
Sawa, Toshio; Takahashi, Sankichi; Takashima, Yoshie.
1983-01-01
Purpose: To efficiently eliminate radioactive materials such as iron oxide and cobalt ions with less heat loss by the use of an electrode assembly applied with a direct current. Constitution: In a reactor water clean-up device adapted to pass reactor water through an electrode assembly comprising at least a pair of anode and cathode applied with a direct current to eliminate various types of ions contained in the reactor water by way of the electrolysis or charge neutralization at the anode, the cathode is constituted with a corrosion resistant grid-like or porous metal plate and a layer to the upper portion of the metal plate filled with a plurality of metal spheres of about 1 - 5 mm diameter, and the anode is made of insoluble porous or spirally wound metal material. (Seki, T.)
Beams on nonlinear elastic foundation
International Nuclear Information System (INIS)
Lukkassen, Dag; Meidell, Annette
2014-01-01
In order to determination vertical deflections and rail bending moments the Winkler model (1867) is often used. This linear model neglects several conditions. For example, by using experimental results, it has been observed that there is a substantial increase in the maximum rail deflection and rail bending moment when considering the nonlinearity of the track support system. A deeper mathematical analysis of the models is necessary in order to obtain better methods for more accurate numerical solutions in the determination of deflections and rail bending moments. This paper is intended to be a small step in this direction
Laser acceleration and nonlinear beam dynamics
International Nuclear Information System (INIS)
Pellegrini, C.
1991-01-01
This research contract covers the period April 1990, September 1991. The work to be done under the contract was theoretical research in the areas of nonlinear beam dynamics and laser acceleration. In this final report we will discuss the motivation for this work and the results obtained
Cockroaches probably cleaned up after dinosaurs.
Directory of Open Access Journals (Sweden)
Peter Vršanský
Full Text Available Dinosaurs undoubtedly produced huge quantities of excrements. But who cleaned up after them? Dung beetles and flies with rapid development were rare during most of the Mesozoic. Candidates for these duties are extinct cockroaches (Blattulidae, whose temporal range is associated with herbivorous dinosaurs. An opportunity to test this hypothesis arises from coprolites to some extent extruded from an immature cockroach preserved in the amber of Lebanon, studied using synchrotron X-ray microtomography. 1.06% of their volume is filled by particles of wood with smooth edges, in which size distribution directly supports their external pre-digestion. Because fungal pre-processing can be excluded based on the presence of large particles (combined with small total amount of wood and absence of damages on wood, the likely source of wood are herbivore feces. Smaller particles were broken down biochemically in the cockroach hind gut, which indicates that the recent lignin-decomposing termite and cockroach endosymbionts might have been transferred to the cockroach gut upon feeding on dinosaur feces.
Cockroaches probably cleaned up after dinosaurs.
Vršanský, Peter; van de Kamp, Thomas; Azar, Dany; Prokin, Alexander; Vidlička, L'ubomír; Vagovič, Patrik
2013-01-01
Dinosaurs undoubtedly produced huge quantities of excrements. But who cleaned up after them? Dung beetles and flies with rapid development were rare during most of the Mesozoic. Candidates for these duties are extinct cockroaches (Blattulidae), whose temporal range is associated with herbivorous dinosaurs. An opportunity to test this hypothesis arises from coprolites to some extent extruded from an immature cockroach preserved in the amber of Lebanon, studied using synchrotron X-ray microtomography. 1.06% of their volume is filled by particles of wood with smooth edges, in which size distribution directly supports their external pre-digestion. Because fungal pre-processing can be excluded based on the presence of large particles (combined with small total amount of wood) and absence of damages on wood, the likely source of wood are herbivore feces. Smaller particles were broken down biochemically in the cockroach hind gut, which indicates that the recent lignin-decomposing termite and cockroach endosymbionts might have been transferred to the cockroach gut upon feeding on dinosaur feces.
ROSEE cleans up after the Cold War
International Nuclear Information System (INIS)
Valenti, M.
1994-01-01
This article describes a robot named ROSEE, designed by engineers at the DOE's Hanford site to minimize the risk of radiation exposure to workers cleaning up to residue left by America's manufacture of nuclear weapons. ROSEE is the acronym for Remotely Operated Sediment Extraction Equipment, a robot designed to vacuum sediment and debris from a nuclear fuels storage pool at the Department of Energy's Hanford nuclear waste storage site in Richland, Wash. The task facing ROSEE involves cleaning out the N basin at Hanford. Work is schedules to begin before the fall. The basin houses nuclear fuel refined during 24 years of the Cold War era. This water-filled structure is 24 feet deep, 87 feet long, and 56 feet wide, approximately three times larger than an Olympic-size swimming pool. Nuclear fuel was contained in honeycomb cells mounted 1 inch from the bottom of the pool. The cells rise 10 feet from the bottom of the basin, and each cell is 21 inches deep and 14 inches wide. The cells now hold radioactive residues that must be removed for final safe disposal
Laser beam propagation in nonlinear optical media
Guha, Shekhar
2013-01-01
""This is very unique and promises to be an extremely useful guide to a host of workers in the field. They have given a generalized presentation likely to cover most if not all situations to be encountered in the laboratory, yet also highlight several specific examples that clearly illustrate the methods. They have provided an admirable contribution to the community. If someone makes their living by designing lasers, optical parametric oscillators or other devices employing nonlinear crystals, or designing experiments incorporating laser beam propagation through linear or nonlinear media, then
Moderator clean-up system in a heavy water reactor
International Nuclear Information System (INIS)
Sasada, Yasuhiro; Hamamura, Kenji.
1983-01-01
Purpose: To decrease the fluctuation of the poison concentration in heavy water moderator due to a heavy water clean-up system. Constitution: To a calandria tank filled with heavy water as poison-containing moderators, are connected both end of a pipeway through which heavy water flows and to which a clean-up device is provided. Strongly basic resin is filled within the clean-up device and a cooler is disposed to a pipeway at the upstream of the clean-up device. In this structure, the temperature of heavy water at the inlet of the clean-up device at a constant level between the temperature at the exit of the cooler and the lowest temperature for the moderator to thereby decrease the fluctuation in the poison concentration in the heavy water moderator due to the heavy water clean-up device. (Moriyama, K.)
Periodic solutions of nonlinear vibrating beams
Directory of Open Access Journals (Sweden)
J. Berkovits
2003-01-01
Full Text Available The aim of this paper is to prove new existence and multiplicity results for periodic semilinear beam equation with a nonlinear time-independent perturbation in case the period is not prescribed. Since the spectrum of the linear part varies with the period, the solvability of the equation depends crucially on the period which can be chosen as a free parameter. Since the period of the external forcing is generally unknown a priori, we consider the following natural problem. For a given time-independent nonlinearity, find periods T for which the equation is solvable for any T-periodic forcing. We will also deal with the existence of multiple solutions when the nonlinearity interacts with the spectrum of the linear part. We show that under certain conditions multiple solutions do exist for any small forcing term with suitable period T. The results are obtained via generalized Leray-Schauder degree and reductions to invariant subspaces.
Coolant clean-up system in nuclear reactor
International Nuclear Information System (INIS)
Tsuburaya, Hirobumi; Akita, Minoru; Shiraishi, Tadashi; Kinoshita, Shoichiro; Okura, Minoru; Tsuji, Akio.
1987-01-01
Purpose: To ensure a sufficient urging pressure at the inlet of a coolant clean-up system pump in a nuclear reactor and eliminate radioactive contaminations to the pump. Constitution: Coolant clean-up system (CUW) pump in a nuclear reactor is disposed to the downstream of a filtration desalter and, for compensating the insufficiency of the urging pressure at the pump inlet, the reactor water intake port to the clean-up system is disposed to the downstream of the after-heat removing pump and the heat exchanger. By compensating the net positive suction head (NPSH) of the clean-up system from the residual heat removing system, the problems of insufficient NPSH for the CUW pump upon reactor shut-down can be dissolved and, accordingly, the reactor clean-up system can be arranged in the order of the heat exchanger, clean-up device and pump. Thus, the CUW pump acts on reactor water after cleaned-up in the clean-up device to reduce the radioactivity contamination to the pump. (Kawakami, Y.)
Diabetes mellitus morbidity in Chernobyl clean-up workers
International Nuclear Information System (INIS)
Tolstaya, E.V.; Ermakova, D.P.; Glinskaya, T.N.
2016-01-01
Acute and total diabetes mellitus morbidity in Chernobyl clean-up workers was examined during 1995-2014 period. During all the period of investigations levels of acute and total morbidity were higher in clean-up workers, than in total Belarusian population. (authors)
Nonlinear transverse vibrations of elastic beams under tension
International Nuclear Information System (INIS)
Ichikawa, Y.H.; Konno, Kimiaki; Wadati, Miki.
1980-02-01
Nonlinear transverse vibrations of elastic beams under end-thrust have been examined with full account of the rigorous nonlinear relation of curvature and deformation of elastic beams. When the beams are subject to tension, the derived equation is shown to be reduced to one of the new integrable evolution equations discovered by us. (author)
Beam stability & nonlinear dynamics. Formal report
Energy Technology Data Exchange (ETDEWEB)
Parsa, Z. [ed.
1996-12-31
his Report includes copies of transparencies and notes from the presentations made at the Symposium on Beam Stability and Nonlinear Dynamics, December 3-5, 1996 at the Institute for Theoretical Physics, University of California, Santa Barbara California, that was made available by the authors. Editing, reduction and changes to the authors contributions were made only to fulfill the printing and publication requirements. We would like to take this opportunity and thank the speakers for their informative presentations and for providing copies of their transparencies and notes for inclusion in this Report.
Beam stability ampersand nonlinear dynamics. Formal report
International Nuclear Information System (INIS)
Parsa, Z.
1996-01-01
This report includes copies of transparencies and notes from the presentations made at the Symposium on Beam Stability and Nonlinear Dynamics, December 3-5, 1996 at the Institute for Theoretical Physics, University of California, Santa Barbara California, that was made available by the authors. Editing, reduction and changes to the authors contributions were made only to fulfill the printing and publication requirements. We would like to take this opportunity and thank the speakers for their informative presentations and for providing copies of their transparencies and notes for inclusion in this Report
Eye pathologies of Chernobyl clean-up workers
International Nuclear Information System (INIS)
Eglite, A.; Ozola, G.; Curbakova, E.
1998-01-01
Diseases of the nervous system and sense organs have become the most significant pathologies of Chernobyl clean-up workers during the last four years. The aim of this work was to evaluate the incidence of eye disorders among Chernobyl clean-up workers to provide more information for health specialists. During the last 10 years, the most common eye pathology has been angiopathia retinae, followed by myopia and cataracta. Statistical analyses showed that the clean-up workers have higher risk to develop angiopathia retinae than the control group. (author)
Overview of magnetic nonlinear beam dynamics in the RHIC
International Nuclear Information System (INIS)
Luo, Y.; Bai, M.; Beebe-Wang, J.; Bengtsson, J.; Calaga, R.; Fischer, W.; Jain, A.; Pilat, F.; Ptitsyn, V.; Malitsky, N.; Robert-Demolaize, G.; Satogata, T.; Tepikian, S.; Tomas, R.; Trbojevic, D.
2009-01-01
In this article we review our studies of nonlinear beam dynamics due to the nonlinear magnetic field errors in the Relativistic Heavy Ion Collider (RHIC). Nonlinear magnetic field errors, including magnetic field errors in interaction regions (IRs), chromatic sextupoles, and sextupole components from arc main dipoles are discussed. Their effects on beam dynamics and beam dynamic aperture are evaluated. The online methods to measure and correct the IR nonlinear field errors, second order chromaticities, and horizontal third order resonance are presented. The overall strategy for nonlinear corrections in RHIC is discussed
Nonlinear space charge effect of bunched beam in linac
International Nuclear Information System (INIS)
Chen Yinbao
1992-02-01
The nonlinear space charge effect due to the nonuniform particle density distribution in bunched beam of a linac is discussed. The formulae of nonlinear space charge effect and nonlinear focusing forces were derived for the bunched beam with Kapchinskij-Vladimirskij (K-V) distribution, waterbag (WB) distribution, parabolic (PA) distribution, and Gauss (GA) distribution in both of the space charge disk model and space charge cylinder model in the waveguide of a linac
Nonlinear wave beams in a piezo semiconducting layer
International Nuclear Information System (INIS)
Bagdoev, A.G.; Shekoyan, A.V.; Danoyan, Z.N.
1997-01-01
The propagation of quasi-monochromatic nonlinear wave in a piezo semiconducting layer taking into account electron-concentration nonlinearity is considered. For such medium the evolution equations for incoming and reflected waves are derived. Nonlinear Schroedinger equations and solutions for narrow beams are obtained. It is shown that symmetry of incoming and reflected waves does not take place. The focusing of beams is investigated.18 refs
Propagation of hypergeometric Gaussian beams in strongly nonlocal nonlinear media
Tang, Bin; Bian, Lirong; Zhou, Xin; Chen, Kai
2018-01-01
Optical vortex beams have attracted lots of interest due to its potential application in image processing, optical trapping and optical communications, etc. In this work, we theoretically and numerically investigated the propagation properties of hypergeometric Gaussian (HyGG) beams in strongly nonlocal nonlinear media. Based on the Snyder-Mitchell model, analytical expressions for propagation of the HyGG beams in strongly nonlocal nonlinear media were obtained. The influence of input power and optical parameters on the evolutions of the beam width and radius of curvature is illustrated, respectively. The results show that the beam width and radius of curvature of the HyGG beams remain invariant, like a soliton when the input power is equal to the critical power. Otherwise, it varies periodically like a breather, which is the result of competition between the beam diffraction and nonlinearity of the medium.
On nonlinear development of beam instability
International Nuclear Information System (INIS)
Popel', S.I.; Tsytovich, V.N.
1990-01-01
Radiation-resonance interactions are taken into account in the problem of dynamics of an electron beam inb plasma. The beam characteristics to be taken into account are determined. Stabilization conditions for beam instability are established
On the dynamics of Airy beams in nonlinear media with nonlinear losses.
Ruiz-Jiménez, Carlos; Nóbrega, K Z; Porras, Miguel A
2015-04-06
We investigate on the nonlinear dynamics of Airy beams in a regime where nonlinear losses due to multi-photon absorption are significant. We identify the nonlinear Airy beam (NAB) that preserves the amplitude of the inward Hänkel component as an attractor of the dynamics. This attractor governs also the dynamics of finite-power (apodized) Airy beams, irrespective of the location of the entrance plane in the medium with respect to the Airy waist plane. A soft (linear) input long before the waist, however, strongly speeds up NAB formation and its persistence as a quasi-stationary beam in comparison to an abrupt input at the Airy waist plane, and promotes the formation of a new type of highly dissipative, fully nonlinear Airy beam not described so far.
Differential quadrature method of nonlinear bending of functionally graded beam
Gangnian, Xu; Liansheng, Ma; Wang, Youzhi; Quan, Yuan; Weijie, You
2018-02-01
Using the third-order shear deflection beam theory (TBT), nonlinear bending of functionally graded (FG) beams composed with various amounts of ceramic and metal is analyzed utilizing the differential quadrature method (DQM). The properties of beam material are supposed to accord with the power law index along to thickness. First, according to the principle of stationary potential energy, the partial differential control formulae of the FG beams subjected to a distributed lateral force are derived. To obtain numerical results of the nonlinear bending, non-dimensional boundary conditions and control formulae are dispersed by applying the DQM. To verify the present solution, several examples are analyzed for nonlinear bending of homogeneous beams with various edges. A minute parametric research is in progress about the effect of the law index, transverse shear deformation, distributed lateral force and boundary conditions.
International Nuclear Information System (INIS)
Gao Jie
2009-01-01
In this paper we treat first some nonlinear beam dynamics problems in storage rings, such as beam dynamic apertures due to magnetic multipoles, wiggles, beam-beam effects, nonlinear space charge effect, and then nonlinear electron cloud effect combined with beam-beam and space charge effects, analytically. This analytical treatment is applied to BEPC II. The corresponding analytical expressions developed in this paper are useful both in understanding the physics behind these problems and also in making practical quick hand estimations. (author)
Myelodysplastic syndromes in Chernobyl clean-up workers.
Gluzman, Daniil F; Sklyarenko, Lilia M; Koval, Stella V; Rodionova, Nataliia K; Zavelevich, Michael P; Ivanivskaya, Tetiana S; Poludnenko, Liudmyla Yu; Ukrainskaya, Nataliia I
2015-10-01
The studies of the recent decades posed the question of the association between radiation exposure and myelodysplastic syndromes (MDS). This association has been proved in secondary MDS originating upon exposure to chemotherapeutics and/or radiation therapy. The long-term study in Japanese atomic (A)-bomb survivors demonstrated the significant linear dose-response for MDS confirming the link between radiation exposure and this form of hematopoietic malignancies. All these findings provide the strong basis for studying MDS in the persons exposed to radiation following the Chernobyl disaster, especially those in the cohort of Chernobyl clean-up workers of 1986-1987. The data on MDS among Chernobyl clean-up workers (1986-1987) diagnosed in 1996-2012 at the reference laboratory of RE Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology are summarized. MDS cases were diagnosed in 23 persons (21 males and 2 females) having been exposed to radiation as clean-up workers of 1986-1987. Refractory anemia (RA) has been detected in 13, refractory anemia with ring sideroblasts (RARS)-in 2, and refractory anemia with excess blasts (RAEB)-in 8 patients. The median age of those MDS patients was 62.0 years. In addition, 5 cases of chronic myelomonocytic leukemia (CMML) were recorded in the group of Chernobyl clean-up workers with the median time of 14.8 years from 1986-1987 to diagnosis. The association between radiation exposure and MDS is discussed. The suggested life-long risk for myelodysplastic syndromes among A-bomb survivors in Japan highlights the importance of the continuing follow-up studies in the affected populations in the post-Chernobyl period.
Cleaning up a GNU/Linux operating system
Oblak , Denis
2018-01-01
The aim of the thesis is to develop an application for cleaning up the Linux operating system that would be able to function on most distributions. The theoretical part discusses the cleaning of the Linux operating system that frees up disk space and allows a better functioning. The cleaning techniques and the existing tools for Linux are systematically reviewed and presented. The following part examines the cleaning of the Windows and MacOS operating systems. The thesis also compares all...
Renewable Natural Gas Clean-up Challenges and Applications
2011-01-13
produced from digesters ─ Animal manure (dairy cows, swine ) ─ Waste water treatment facilities > Methane from Landfills > RNG produced from...LNG) for vehicle fuel ─Ft. Lewis — Anaerobic digestion of waste water for production of hydrogen as a fuel cell vehicle fuel ─SCRA * – Landfill gas...BE CLEANED- UP AND PLACED IN THE NATURAL GAS PIPELINE SYSTEM 6 GTI RNG Project Examples >Example GTI Projects: ─Gills Onions— Anaerobic
Solution of Contact Problems for Nonlinear Gao Beam and Obstacle
Directory of Open Access Journals (Sweden)
J. Machalová
2015-01-01
Full Text Available Contact problem for a large deformed beam with an elastic obstacle is formulated, analyzed, and numerically solved. The beam model is governed by a nonlinear fourth-order differential equation developed by Gao, while the obstacle is considered as the elastic foundation of Winkler’s type in some distance under the beam. The problem is static without a friction and modeled either using Signorini conditions or by means of normal compliance contact conditions. The problems are then reformulated as optimal control problems which is useful both for theoretical aspects and for solution methods. Discretization is based on using the mixed finite element method with independent discretization and interpolations for foundation and beam elements. Numerical examples demonstrate usefulness of the presented solution method. Results for the nonlinear Gao beam are compared with results for the classical Euler-Bernoulli beam model.
Thyroid disorders in Chernobyl clean-up workers from Latvia
International Nuclear Information System (INIS)
Kurjane, N.; Orlikovs, G.; Ritenberga, R.; Skudra, M.; Lemane, R.; Lemanis, A.; Curbakova, E.; Groma, V.; Socnevs, A.
1999-01-01
The condition of thyroid was examined in 2188 Chernobyl clean-up workers residing in Latvia and a control group consisting of 1041 employees of the Ministry of International Affairs. Thyroid examinations included palpation, ultrasonography, selective scintigraphy and detection of the level of thyroid hormones in blood serum:L STH (thyroid-stimulating hormone), total T3 (triiodothyronine), and T4 (thyroxine). Thyroid was registered in 394 Chernobyl clean-up workers. Of these cases, 28 patients with suspected thyroid cancer were operated, and morphological examinations revealed papillary adenocarcinoma (in 5 patients), follicular adenocarcinoma (2), nodular colloid goiter (16); toxic diffuse goiter (1), papillary-follicular adenoma (3), and chronic thyroiditis (1). It was determined that the thyroid pathology in the Chernobyl clean-up workers had a tendency to progress (27 cases in 1987 versus 394 cases in 1998 in total; and absence of thyroid cancer in 1987, compared with 7 cases in 1998); thyroid nodules increased twice (64 cases in 1997, compare with 126 cases in 1998). (author)
Coherent Nonlinear Longitudinal Phenomena in Unbunched Synchrotron Beams
Energy Technology Data Exchange (ETDEWEB)
Spentzouris, Linda Klamp [Northwestern U.
1996-12-01
Coherent nonlinear longitudinal phenomena are studied in proton and antiproton synchrotron beams. Theoretical development done in the eld of plasma physics for resonant wave-wave coupling is applied to the case of a particle beam. Results are given from experiments done to investigate the nature of the weakly nonlinear three-wave coupling processes known as parametric coupling and echoes. Storage ring impedances are shown to amplify the parametric coupling process, underlining the possibility that machine impedances might be extracted from coupling events instigated by external excitation. Echo amplitudes are demonstrated to be sensitive to diusion processes, such as intrabeam scattering, which degrade a beam. The result of a fast diusion rate measurement using echo amplitudes is presented. In addition to the wave-wave interactions, observations of moderately nonlinear waveparticle interactions are also included. The manifestations of these interactions that are documented include nonlinear Landau damping, higher harmonic generation, and signs of the possible formation of solitons.
Some nonlinear problems in the manipulation of beams
International Nuclear Information System (INIS)
Sessler, A.M.
1990-01-01
An overview is given of nonlinear problems that arise in the manipulation of beams. Beams can be made of material particles or photons, can be intense or dilute, can be energetic or not, and they can be propagating in vacuum or in a medium. The nonlinear aspects of the motion are different in each case, and this diversity of behavior is categorized. Many examples are given, which serves to illustrate the categorization and, furthermore, display the richness of behavior encountered in the physics of beams. 25 refs., 5 figs
Nonlinear interaction of colliding beams in particle storage rings
International Nuclear Information System (INIS)
Herrera, J.C.; Month, M.
1979-01-01
When two beams of high energy particles moving in opposite directions are brought into collision, a large amount of energy is available for the production of new particles. However to obtain a sufficiently high event rate for rare processes, such as the production of the intermediate vector boson (Z 0 and W +- ), large beam currents are also required. Under this circumstance, the high charge density of one beam results in a classical electromagnetic interaction on the particles in the other beam. This very nonlinear space charge force, caled the beam-beam force, limits the total circulating charge and, thereby, the ultimate performance of the colliding ring system. The basic nature of the beam-beam force is discussed, indicating how it is quite different in the case of continuous beams, which cross each other at an angle as compared to the case of bunched beams which collide head-on. Some experimental observations on the beam-beam interaction in proton-proton and electron-positron beams are then reviewed and interpreted. An important aspect of the beam-beam problem in storage rings is to determine at what point in the analysis of the particle dynamics is it relevant to bring in the concepts of stochasticity, slow diffusion, and resonance overlap. These ideas are briefly discussed
Optical Beams in Nonlocal Nonlinear Media
DEFF Research Database (Denmark)
Królikowski, W.; Bang, Ole; Wyller, J.
2003-01-01
We discuss propagation of optical beams in nonlocal Kerr-like media with the nonlocality of general form. We study the effect of nonlocality on modulational instability of the plane wave fronts, collapse of finite beams and formation of spatial solitons....
US DoE clean-up programme: an update
International Nuclear Information System (INIS)
Whitfield, R.P.
1993-01-01
The Office of Environmental Restoration and Waste Management (EM) was established in 1989, when the US DoE's priority changed from nuclear weapons production to environmental clean-up. Both the decreased need for nuclear weapons due to global changes and decreasing threats from the Cold War, and the increased emphasis on environmental stewardship contributed to this change. The Environmental Restoration (ER) programme within EM was tasked to ensure that risks to human health and the environment posed by the DoE's past operations at its nuclear facilities and sites are eliminated or reduced to prescribed, safe levels. This article is a progress report on the programme. (author)
Implications of various dispersants on biofilm clean up processes
Energy Technology Data Exchange (ETDEWEB)
Beardwood, E.S.; Therrien, J.K.
1999-07-01
A microbiologically fouled industrial cooling water system was investigated utilizing a portable corrosion and fouling monitor according to the NACE RP0189-951 Standard. Baseline data was established and at which time the monitor was subjected to various dispersants (3) typically used for organic and microbiological deposit removal. The results of this in-field, side stream, experiment on a dynamic system will be presented. A number of key points and factors influencing the performance of the foulant clean up will also be discussed.
The TMI-2 clean-up project collection and databases
International Nuclear Information System (INIS)
Osif, B.A.; Conkling, T.W.
1996-01-01
A publicly accessible collection containing several thousand of the videotapes, photographs, slides and technical reports generated during the clean-up of the TMI-2 reactor has been established by the Pennsylvania State University Libraries. The collection is intended to serve as a technical resource for the nuclear industry as well as the interested public. Two Internet-searchable databases describing the videotapes and technical reports have been created. The development and use of these materials and databases are described in this paper. (orig.)
Temporal nonlinear beam dynamics in infiltrated photonic crystal fibers
DEFF Research Database (Denmark)
Bennet, Francis; Rosberg, Christian Romer; Neshev, Dragomir N.
Liquid-infiltrated photonic crystal fibers (PCFs) offer a new way of studying light propagation in periodic and discrete systems. A wide range of available fiber structures combined with the ease of infiltration opens up a range of novel experimental opportunities for optical detection and bio...... the evolution of the fiber output beam in the few micro or milliseconds after the beam is turned on. The characterization of the temporal behavior of the thermal nonlinear response provides important information about the nonlocality associated with heat diffusion inside the fiber, thus enabling studies of long...... and technological potential of liquid-infiltrated PCFs it is important to understand the temporal dynamics of nonlinear beam propagation in such structures. In this work we consider thermally induced spatial nonlinear effects in infiltrated photonic crystal fibers. We experimentally study the temporal dynamics...
Laboratory beam-plasma interactions: linear and nonlinear
International Nuclear Information System (INIS)
Christiansen, P.J.; Jain, V.K.; Bond, J.W.
1982-01-01
The present investigation is concerned with the configuration of a cool plasma (often magnetized axially) penetrated by an injected electron beam. The attempt is made to demonstrate that despite unavoidable scaling limitations, laboratory experiments can illuminate, in a controlled fashion, details of beam plasma interaction processes in a way which will never be possible in the space plasma physics. In view of the increasing interest in high frequency instabilities in the auroral zone, the possibilities for interesting cross fertilizations of the two fields appear to be extensive. The linear theory is considered along with low frequency couplings and indirect effects. Attention is given to the evidence for the existence of exponentially growing instabilities in beam plasma interactions. The consequences of such instabilities are also explored and some processes of nonlinear processes are discussed, taking into account quasi-linear effects, trapping effects, nonlinear effects, trapping effects, nonlinear wave-wave interactions, and self-modulation and cavitation. 80 references
Composite Beam Theory with Material Nonlinearities and Progressive Damage
Jiang, Fang
Beam has historically found its broad applications. Nowadays, many engineering constructions still rely on this type of structure which could be made of anisotropic and heterogeneous materials. These applications motivate the development of beam theory in which the impact of material nonlinearities and damage on the global constitutive behavior has been a focus in recent years. Reliable predictions of these nonlinear beam responses depend on not only the quality of the material description but also a comprehensively generalized multiscale methodology which fills the theoretical gaps between the scales in an efficient yet high-fidelity manner. The conventional beam modeling methodologies which are built upon ad hoc assumptions are in lack of such reliability in need. Therefore, the focus of this dissertation is to create a reliable yet efficient method and the corresponding tool for composite beam modeling. A nonlinear beam theory is developed based on the Mechanics of Structure Genome (MSG) using the variational asymptotic method (VAM). The three-dimensional (3D) nonlinear continuum problem is rigorously reduced to a one-dimensional (1D) beam model and a two-dimensional (2D) cross-sectional analysis featuring both geometric and material nonlinearities by exploiting the small geometric parameter which is an inherent geometric characteristic of the beam. The 2D nonlinear cross-sectional analysis utilizes the 3D material models to homogenize the beam cross-sectional constitutive responses considering the nonlinear elasticity and progressive damage. The results from such a homogenization are inputs as constitutive laws into the global nonlinear 1D beam analysis. The theoretical foundation is formulated without unnecessary kinematic assumptions. Curvilinear coordinates and vector calculus are utilized to build the 3D deformation gradient tensor, of which the components are formulated in terms of cross-sectional coordinates, generalized beam strains, unknown warping
A software tool for soil clean-up technology selection
International Nuclear Information System (INIS)
Vranes, S.; Gonzalez-Valencia, E.; Lodolo, A.; Miertus, S.
2002-01-01
Soil remediation is a difficult, time-consuming and expensive operation. A variety of mature and emerging soil remediation technologies is available and future trends in remediation will include continued competition among environmental service companies and technology developers, which will definitely result in further increase in the clean-up options. Consequently, the demand has enhanced developing decision support tools that could help the decision makers to select the most appropriate technology for the specific contaminated site, before the costly remedial actions are taken. Therefore, a software tool for soil clean-up technology selection is currently being developed with the aim of closely working with human decision makers (site owners, local community representatives, environmentalists, regulators, etc.) to assess the available technologies and preliminarily select the preferred remedial options. The analysis for the identification of the best remedial options is based on technical, financial, environmental, and social criteria. These criteria are ranked by all involved parties to determine their relative importance for a particular project. (author)
Aviation safely management, Valdez oil spill clean-up
International Nuclear Information System (INIS)
Friesenhahn, M.J.; McKeown, W.L.; Williams, R.G.
1993-01-01
The March 24, 1989 Exxon Valdez oil spill in Alaska's Prince William Sound (PWS) resulted in an unprecedented mobilization of personnel and oil spill clean-up equipment. This paper describes the comprehensive safety management system implemented for aviation operations supporting the clean-up response in PWS and the Gulf of Alaska (GOA). Aviation support operations quickly expanded to over 100 aircraft obtained from numerous sources. Beginning with early surveillance flights, aviation operations were subject to comprehensive safety management programs, including safety assessments, minimum flight weather criteria, operational standards and procedures, air carrier qualifications, equipment and procedure audits, and emergency response. Communication networks and flight following procedures were established, arctic survival training was conducted, and a full complement of survival equipment was required. These programs were largely responsible for safety performance of the spill response effort-during the 1989-92 response activities, over 56,000 flight hours, 159,000 equivalent passengers, and 20,000 tons of cargo were handled without an aviation related injury. The programs are applicable to offshore development and operational activities, particularly those located in more remote, severe environments
Cleaning up commingled uranium mill tailings: is Federal assistance necessary
International Nuclear Information System (INIS)
1979-01-01
GAO was asked to determine whether Federal assistance should be given to operating mill owners that have processed uranium for sale to both government and industry and, thus, generated residual radioactive wastes. The wastes generated for both government and commercial use are called commingled uranium mill tailings. GAO recommends that the Congress provide assistance to active mill owners to share in the cost of cleaning up that portion of the tailings which were produced under Federal contract. Further, GAO believes that the Congress should also consider having the Federal government assist those mills who acted in good faith in meeting all legal requirements pertaining to controlling the mill tailings that were generated for commercial purposes and for which the Federal government is now requiring retroactive remedial action. At the same time, the Congress should make sure that this action establishes no precedent for the Federal government assuming the financial responsibility of cleaning up other non-Federal nuclear facilities and wastes, including those mill tailings generated after the date when the Federal government notified industry that the failings should be controlled
Spatiotemporal light-beam compression from nonlinear mode coupling
Krupa, Katarzyna; Tonello, Alessandro; Couderc, Vincent; Barthélémy, Alain; Millot, Guy; Modotto, Daniele; Wabnitz, Stefan
2018-04-01
We experimentally demonstrate simultaneous spatial and temporal compression in the propagation of light pulses in multimode nonlinear optical fibers. We reveal that the spatial beam self-cleaning recently discovered in graded-index multimode fibers is accompanied by significant temporal reshaping and up to fourfold shortening of the injected subnanosecond laser pulses. Since the nonlinear coupling among the modes strongly depends on the instantaneous power, we explore the entire range of the nonlinear dynamics with a single optical pulse, where the optical power is continuously varied across the pulse profile.
Nonlinear wave-beam kinetic equilibrium in decelerating systems
International Nuclear Information System (INIS)
Grishin, V.K.; Shaposhnikova, E.N.
1981-01-01
The equilibrium state of the wave-beam system arising during the interaction of a particle beam and excited electromagnetic wave has been investigated on the basis of the analysis of the exact polution of a non-linear self-consistent linear equation using the complete system of conservation laws. A waveguide with a dielectric filler, into which a monoenergetic particle beam magnetized in a transverse plane is continuously injected, is used as a model of an decelerating system. A dispersion equation describing the system state and expression for the evaluation of efficiency of the beam energy conversion to the field energy have been obtained. It is concluded that larae fields and high efficiency of energy conversion are achieved during the marked beam reconstruction. States with different values of current and beam velocity but similar amplitudes of a longitudinal field are possible in the system considered [ru
Nonlinear analysis of shear deformable beam-columns partially ...
African Journals Online (AJOL)
In this paper, a boundary element method is developed for the nonlinear analysis of shear deformable beam-columns of arbitrary doubly symmetric simply or multiply connected constant cross section, partially supported on tensionless Winkler foundation, undergoing moderate large deflections under general boundary ...
Bending of a nonlinear beam reposing on an unilateral foundation
Directory of Open Access Journals (Sweden)
Machalová J.
2011-06-01
Full Text Available This article is going to deal with bending of a nonlinear beam whose mathematical model was proposed by D. Y. Gao in (Gao, D. Y., Nonlinear elastic beam theory with application in contact problems and variational approaches,Mech. Research Communication, 23 (1 1996. The model is based on the Euler-Bernoulli hypothesis and under assumption of nonzero lateral stress component enables moderately large deflections but with small strains. This is here extended by the unilateralWinkler foundation. The attribution unilateral means that the foundation is not connected with the beam. For this problem we demonstrate a mathematical formulation resulting from its natural decomposition which leads to a saddle-point problem with a proper Lagrangian. Next we are concerned with methods of solution for our problem by means of the finite element method as the paper (Gao, D. Y., Nonlinear elastic beam theory with application in contact problems and variational approaches, Mech. Research Communication, 23 (1 1996 has no mention of it. The main alternatives are here the solution of a system of nonlinear nondifferentiable equations or finding of a saddle point through the use of the augmented Lagrangian method. This is illustrated by an example in the final part of the article.
Laser beam propagation in non-linearly absorbing media
CSIR Research Space (South Africa)
Forbes, A
2006-08-01
Full Text Available Many analytical techniques exist to explore the propagation of certain laser beams in free space, or in a linearly absorbing medium. When the medium is nonlinearly absorbing the propagation must be described by an iterative process using the well...
Nonlinear Vibrations of Cantilever Timoshenko Beams: A Homotopy Analysis
Directory of Open Access Journals (Sweden)
Shahram Shahlaei-Far
Full Text Available Abstract This study analyzes the fourth-order nonlinear free vibration of a Timoshenko beam. We discretize the governing differential equation by Galerkin's procedure and then apply the homotopy analysis method (HAM to the obtained ordinary differential equation of the generalized coordinate. We derive novel analytical solutions for the nonlinear natural frequency and displacement to investigate the effects of rotary inertia, shear deformation, pre-tensile loads and slenderness ratios on the beam. In comparison to results achieved by perturbation techniques, this study demonstrates that a first-order approximation of HAM leads to highly accurate solutions, valid for a wide range of amplitude vibrations, of a high-order strongly nonlinear problem.
A Simple Model for Nonlinear Confocal Ultrasonic Beams
Zhang, Dong; Zhou, Lin; Si, Li-Sheng; Gong, Xiu-Fen
2007-01-01
A confocally and coaxially arranged pair of focused transmitter and receiver represents one of the best geometries for medical ultrasonic imaging and non-invasive detection. We develop a simple theoretical model for describing the nonlinear propagation of a confocal ultrasonic beam in biological tissues. On the basis of the parabolic approximation and quasi-linear approximation, the nonlinear Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation is solved by using the angular spectrum approach. Gaussian superposition technique is applied to simplify the solution, and an analytical solution for the second harmonics in the confocal ultrasonic beam is presented. Measurements are performed to examine the validity of the theoretical model. This model provides a preliminary model for acoustic nonlinear microscopy.
Cleaning-up abandoned uranium mines in Saskatchewan's North
International Nuclear Information System (INIS)
Schramm, L.L.
2012-01-01
Thirty-six now-abandoned uranium mine and mill sites were developed and operated on or near Lake Athabasca, in Northern Saskatchewan, Canada, from approximately 1957 through 1964. During their operating lifetimes these mines produced large quantities of ore and tailings. After closure in the 1960's, these mine and mill sites were abandoned with little remediation and no reclamation being done. The governments of Canada and Saskatchewan are now funding the cleanup of these abandoned northern uranium mine and mill sites and have contracted the management of the project to the Saskatchewan Research Council (SRC). The clean-up activity is underway, with work at many of the smaller sites largely completed, work at the Gunnar site well underway, and a beginning made at the Lorado site. This lecture presents an overview of these operations. (author)
Postprocessing method to clean up streaks due to noisy detectors
International Nuclear Information System (INIS)
Tuy, H.K.; Mattson, R.A.
1990-01-01
This paper reports that occasionally, one of the thousands of detectors in a CT scanner will intermittently produce erroneous data, creating streaks in the reconstructed image. The authors propose a method to identify and clean up the streaks automatically. To find the rays along which the data values are bad, a binary image registering the edges of the original image is created. Forward projection is applied to the binary image to single out edges along rays. Data along views containing the identified bad rays are estimated by means of forward projecting the original image. Back projection of the negative of the estimated convolved data along these views onto the streaky image will remove streaks from the image. Image enhancement is achieved by means of back projecting the convolved data estimated from the image after the streak removal along views of bad rays
Conceptual design of an emergency tritium clean-up system
International Nuclear Information System (INIS)
Muller, M.E.
1978-01-01
The Los Alamos Scientific Laboratory (LASL) has been selected by the Department of Energy (DOE) to design, build, and operate a facility to demonstrate the operability of the tritium-related subsystems that would be required to successfully develop fusion reactor systems. An emergency tritium clean-up subsystem (ETC) for this facility will be designed to remove tritium from the cell atmosphere if an accident causes the primary and secondary tritium containment to be breached. Conceptually, the ETC will process cell air at the rate of 0.65 actual m 3 /s and will achieve an overall decontamination factor of 10 6 per tritium oxide (T 2 O). Following the maximum credible release of 100 g of tritium, the ETC will restore the cell to opertional status within 24 h without a significant release of tritium to the environment
Cleaning up gasoline will increase refinery hydrogen demand
International Nuclear Information System (INIS)
Pretorius, E.B.; Muan, A.
1992-01-01
This paper reports that hydrogen needs will increase two to five times as the world turns its attention to cleaning up engine exhaust. The subject of fuel trends and hydrogen needs at Foster Wheeler USA Corp.'s Hydrogen Plant Conference, June 2--4, in Orlando was addressed. The conference was attended by more than 100 people from 12 different countries. Drawing on knowledge from over 1 billion scfd of total installed hydrogen plant capacity, Foster Wheeler experts presented papers in the fields of steam reforming, partial oxidation (with all feedstocks, from natural gas to resids and coal), and steam reformer design. Other industry specialists gave papers on refinery balances, markets, coal feedstocks, utility systems, and components for hydrogen plants
Clean-up criteria for remediation of contaminated soils
International Nuclear Information System (INIS)
Nguyen, H.D.; Wilson, J.R.; Sato, Chikashi
1997-01-01
'How clean is clean?' is a question commonly raised in the remediation of contaminated soils. To help with the answer, criteria are proposed to serve as guidelines for remedial actions and to define a clean-up level such that the remaining contaminant residuals in the soil will not violate the Drinking Water Standards (DWS). The equations for computing those criteria are developed from the principle of conservation of mass and are functions of the maximum concentration level in the water (MCL) and the sorption coefficient. A multiplier, ranging from 10 to 1000, is also factored into the soil standard equation to reflect the effectiveness of various remediation techniques. Maximum allowable concentration in the soil (MSCL) is presented for several contaminants which are being regulated at the present time. Future modifications are recommended for better estimates of the MSCLs as additional transport mechanisms are incorporated to account for other potentially dominant effects
Condensate clean up control system with distributed DDC
International Nuclear Information System (INIS)
Yoshioka, K.; Tazima, T.; Nakamura, O.; Kobayashi, S.
1980-01-01
In the operation of the Condensate Clean Up System in BWR plants, regeneration intervals of the demineralizer are not equal and there is no base to determine the interval, which is usually decided by operator's experience. Regeneration of resin is, therefore, sometimes performed too early, leaving much of the capacity of the resin unused. In order to improve such operations efforts were made to equalize the operating time difference of two sequential demineralizers, to control the initial flow into newly-connected demineralizers. The economic and efficient operation of this system, along with the reduction of radioactive resins and the safety supervisory function can be achieved by the distributed DDC with a microprocessor. (LL)
Plutonium contamination at Maralinga - dosimetry and clean-up criteria
International Nuclear Information System (INIS)
Cooper, M.B.; Martin, L.J.; O'Brien, R.S.; Williams, G.A.
1998-01-01
An area of South Australia remained contaminated following British nuclear weapons tests at Maralinga during 1955 - 1963. Of importance is the long-lived 239-Pu of which some 24 kg was explosively dispersed in several 'minor trials'. The extent, quantities and physical characteristics of the plutonium have been assessed and estimates of dose, dominated by the inhalation pathway in the critical group of Aborigines living a semi-traditional lifestyle, have been made for potential occupants. Rehabilitation of the most contaminated areas is underway, involving scraping of surface soil and burial at depth on site. Dosimetry, together with social and economic factors, underpins the setting of clean-up criteria in terms of activity concentrations averaged over large areas and permissible concentrations of contaminated particles. The possibility of intentional behaviour such as fragment scavenging has also influenced limits on particulate contamination.The standard for this intervention is that the annual committed dose, for any scenario involving permanent occupancy by semi-traditional Aborigines, will be less than 5 mSv. In fact, following the clean-up, annual doses are not expected to exceed 1 mSv for all realistic scenarios. The possibility of intentional behaviour, such as fragment scavenging, has led to limits on particulate contamination. Three plutonium-contaminated sites have been treated by soil-removal. At Taranaki, the most contaminated site, by limiting the activity of the remaining soil to below about 400 kBq/m2 of 239Pu, and by limiting occupancy factors to those typical of hunting activities in a particular location (0.8%), the dose criteria will be met. An area of about 1.5 km 2 has been treated by removal of surface soil at Taranaki. At the other two sites, with no occupancy constraints, more stringent soil-removal criteria have been applied
Laboratory beam-plasma interactions linear and nonlinear
International Nuclear Information System (INIS)
Christiansen, P.J.; Bond, J.W.; Jain, V.K.
1982-01-01
This chapter attempts to demonstrate that despite unavoidable scaling limitations, laboratory experiments can uncover details of beam plasma interaction processes which could never be revealed through space plasma physics. Topics covered include linear theory, low frequency couplings, indirect effects, nonlinear effects, quasi-linear effects, trapping effects, nonlinear wave-wave interactions, and self modulation and cavitation. Unstable electrostatic waves arising from an exchange of energy with the ''free energy'' beam features are considered as kinetic and as hydrodynamic, or fluid, instabilities. The consequences of such instabilities (e.g. when the waves have grown to a finite level) are examined and some studies are reviewed which have attempted to understand how the free energy originally available in the beam is redistributed to produce a final state of equilibrium turbulence
Alternative Fuels Data Center: Virginia Cleans up With Natural Gas Refuse
Trucks Virginia Cleans up With Natural Gas Refuse Trucks to someone by E-mail Share Alternative Fuels Data Center: Virginia Cleans up With Natural Gas Refuse Trucks on Facebook Tweet about Alternative Fuels Data Center: Virginia Cleans up With Natural Gas Refuse Trucks on Twitter Bookmark Alternative
Nonlinear Response of Cantilever Beams to Combination and Subcombination Resonances
Directory of Open Access Journals (Sweden)
Ali H. Nayfeh
1998-01-01
Full Text Available The nonlinear planar response of cantilever metallic beams to combination parametric and external subcombination resonances is investigated, taking into account the effects of cubic geometric and inertia nonlinearities. The beams considered here are assumed to have large length-to-width aspect ratios and thin rectangular cross sections. Hence, the effects of shear deformations and rotatory inertia are neglected. For the case of combination parametric resonance, a two-mode Galerkin discretization along with Hamilton’s extended principle is used to obtain two second-order nonlinear ordinary-differential equations of motion and associated boundary conditions. Then, the method of multiple scales is applied to obtain a set of four first-order nonlinear ordinary-differential equations governing the modulation of the amplitudes and phases of the two excited modes. For the case of subcombination resonance, the method of multiple scales is applied directly to the Lagrangian and virtual-work term. Then using Hamilton’s extended principle, we obtain a set of four first-order nonlinear ordinary-differential equations governing the amplitudes and phases of the two excited modes. In both cases, the modulation equations are used to generate frequency- and force-response curves. We found that the trivial solution exhibits a jump as it undergoes a subcritical pitchfork bifurcation. Similarly, the nontrivial solutions also exhibit jumps as they undergo saddle-node bifurcations.
Nonlinear analysis of a relativistic beam-plasma cyclotron instability
Sprangle, P.; Vlahos, L.
1986-01-01
A self-consistent set of nonlinear and relativistic wave-particle equations are derived for a magnetized beam-plasma system interacting with electromagnetic cyclotron waves. In particular, the high-frequency cyclotron mode interacting with a streaming and gyrating electron beam within a background plasma is considered in some detail. This interaction mode may possibly find application as a high-power source of coherent short-wavelength radiation for laboratory devices. The background plasma, although passive, plays a central role in this mechanism by modifying the dielectric properties in which the magnetized electron beam propagates. For a particular choice of the transverse beam velocity (i.e., the speed of light divided by the relativistic mass factor), the interaction frequency equals the nonrelativistic electron cyclotron frequency times the relativistic mass factor. For this choice of transverse beam velocity the detrimental effects of a longitudinal beam velocity spread is virtually removed. Power conversion efficiencies in excess of 18 percent are both analytically calculated and obtained through numerical simulations of the wave-particle equations. The quality of the electron beam, degree of energy and pitch angle spread, and its effect on the beam-plasma cyclotron instability is studied.
Geometrical theory of nonlinear phase distortion of intense laser beams
International Nuclear Information System (INIS)
Glaze, J.A.; Hunt, J.T.; Speck, D.R.
1975-01-01
Phase distortion arising from whole beam self-focusing of intense laser pulses with arbitrary spatial profiles is treated in the limit of geometrical optics. The constant shape approximation is used to obtain the phase and angular distribution of the geometrical rays in the near field. Conditions for the validity of this approximation are discussed. Geometrical focusing of the aberrated beam is treated for the special case of a beam with axial symmetry. Equations are derived that show both the shift of the focus and the distortion of the intensity distribution that are caused by the nonlinear index of refraction of the optical medium. An illustrative example treats the case of beam distortion in a Nd:Glass amplifier
PRP: The Proven Solution for Cleaning Up Oil Spills
2006-01-01
The basic technology behind PRP is thousands of microcapsules, tiny balls of beeswax with hollow centers. Water cannot penetrate the microcapsule s cell, but oil is absorbed right into the beeswax spheres as they float on the water s surface. This way, the contaminants, chemical compounds that originally come from crude oil such as fuels, motor oils, or petroleum hydrocarbons, are caught before they settle. PRP works well as a loose powder for cleaning up contaminants in lakes and other ecologically fragile areas. The powder can be spread over a contaminated body of water or soil, and it will absorb contaminants, contain them in isolation, and dispose of them safely. In water, it is important that PRP floats and keeps the oil on the surface, because, even if oil exposure is not immediately lethal, it can cause long-term harm if allowed to settle. Bottom-dwelling fish exposed to compounds released after oil spills may develop liver disease, in addition to reproductive and growth problems. This use of PRP is especially effective for environmental cleanup in sensitive areas like coral reefs and mangroves.
Major clean-up effort in the ATLAS cavern
Marzio Nessi
On Tuesday 10 October, 58 ATLAS collaborators volunteered to give a hand for a major clean-up of the ATLAS detector prior to the toroid magnet ramp-up. This special task monopolised all of the technical coordination team and eight supervisors to oversee the volunteers who were assigned to two separate five-hour shifts. The volunteers removed all sorts of loose material inside and outside the detector, focusing mainly on potentially magnetic material lost inside the detector and dirt accumulated over several months, not to mention zillions of clipped cable ties! The technical crew provided 120 garbage bags and all were used. All sorts of material that had been lost inside the detector by various people was retrieved, in particular small tools which could potentially damage the detector, as well as metallic fillings hazardous for the electronics once the magnet will be ramped up. A more detailed inspection followed for all the inside of the detector, making sure the current on the magnet could be raised to 5KA ...
Energy Technology Data Exchange (ETDEWEB)
Stancari, Giulio
2014-09-11
Electron lenses are pulsed, magnetically confined electron beams whose current-density profile is shaped to obtain the desired effect on the circulating beam. Electron lenses were used in the Fermilab Tevatron collider for bunch-by-bunch compensation of long-range beam-beam tune shifts, for removal of uncaptured particles in the abort gap, for preliminary experiments on head-on beam-beam compensation, and for the demonstration of halo scraping with hollow electron beams. Electron lenses for beam-beam compensation are being commissioned in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). Hollow electron beam collimation and halo control were studied as an option to complement the collimation system for the upgrades of the Large Hadron Collider (LHC) at CERN; a conceptual design was recently completed. Because of their electric charge and the absence of materials close to the proton beam, electron lenses may also provide an alternative to wires for long-range beam-beam compensation in LHC luminosity upgrade scenarios with small crossing angles. At Fermilab, we are planning to install an electron lens in the Integrable Optics Test Accelerator (IOTA, a 40-m ring for 150-MeV electrons) as one of the proof-of-principle implementations of nonlinear integrable optics to achieve large tune spreads and more stable beams without loss of dynamic aperture.
Loss of Energy Concentration in Nonlinear Evolution Beam Equations
Garrione, Maurizio; Gazzola, Filippo
2017-12-01
Motivated by the oscillations that were seen at the Tacoma Narrows Bridge, we introduce the notion of solutions with a prevailing mode for the nonlinear evolution beam equation u_{tt} + u_{xxxx} + f(u)= g(x, t) in bounded space-time intervals. We give a new definition of instability for these particular solutions, based on the loss of energy concentration on their prevailing mode. We distinguish between two different forms of energy transfer, one physiological (unavoidable and depending on the nonlinearity) and one due to the insurgence of instability. We then prove a theoretical result allowing to reduce the study of this kind of infinite-dimensional stability to that of a finite-dimensional approximation. With this background, we study the occurrence of instability for three different kinds of nonlinearities f and for some forcing terms g, highlighting some of their structural properties and performing some numerical simulations.
Simple computer model for the nonlinear beam--beam interaction in ISABELLE
International Nuclear Information System (INIS)
Herrera, J.C.; Month, M.; Peierls, R.F.
1979-03-01
The beam--beam interaction for two counter-rotating continuous proton beams crossing at an angle can be simulated by a 1-dimensional nonlinear force. The model is applicable to ISABELLE as well as to the ISR. Since the interaction length is short compared with the length of the beam orbit, the interaction region is taken to be a point. The problem is then treated as a mapping with the remainder of the system taken to be a rotation of phase given by the betatron tune of the storage ring. The evolution of the mean square amplitude of a given distribution of particles is shown for different beam--beam strengths. The effect of round-off error with resulting loss of accuracy for particle trajectories is discussed. 3 figures
A nonlinear beam model to describe the postbuckling of wide neo-Hookean beams
Lubbers, Luuk A.; van Hecke, Martin; Coulais, Corentin
2017-09-01
Wide beams can exhibit subcritical buckling, i.e. the slope of the force-displacement curve can become negative in the postbuckling regime. In this paper, we capture this intriguing behaviour by constructing a 1D nonlinear beam model, where the central ingredient is the nonlinearity in the stress-strain relation of the beams constitutive material. First, we present experimental and numerical evidence of a transition to subcritical buckling for wide neo-Hookean hyperelastic beams, when their width-to-length ratio exceeds a critical value of 12%. Second, we construct an effective 1D energy density by combining the Mindlin-Reissner kinematics with a nonlinearity in the stress-strain relation. Finally, we establish and solve the governing beam equations to analytically determine the slope of the force-displacement curve in the postbuckling regime. We find, without any adjustable parameters, excellent agreement between the 1D theory, experiments and simulations. Our work extends the understanding of the postbuckling of structures made of wide elastic beams and opens up avenues for the reverse-engineering of instabilities in soft and metamaterials.
Using Phytoremediation to Clean Up Contamination at Military Installations
International Nuclear Information System (INIS)
Zellmer, S.D.; Hinchman, R.R.; Negri, M.C.; Schneider, J.F.; Gatliff, E.G.
1997-07-01
During and following World War II, wastes from the production of munitions and other military materials were disposed of using the best available practices acceptable at that time. However, these disposal methods often contaminated soil and groundwater with organic compounds and metals that require cleanup under current regulations. An emerging technology for cleaning contaminated soils and shallow groundwater is phytoremediation, an environmentally friendly, low- cost, and low-tech process. Phytoremediation encompasses all plant- influenced biological, chemical, and physical processes that aid in the uptake, degradation, and metabolism of contaminants by either plants or free-living organisms in the plant's rhizosphere. A phytoremediation system can be viewed as a biological, solar-driven, pump-and-treat system with an extensive, self-extending uptake network (the root system) that enhances the soil and below-ground ecosystem for subsequent productive use. Argonne National Laboratory (ANL) has been conducting basic and applied research in phytoremediation since 1990. Initial greenhouse studies evaluated salt-tolerant wetland plants to clean UP and reduce the volume of salty 'produced water' from petroleum wells. Results of these studies were used to design a bioreactor for processing produced water that is being demonstrated at a natural gas well in Oklahoma; this system can reduce produced water volume by about 75% in less than eight days, representing substantial savings in waste disposal cost. During 1994, ANL conducted a TNT plant uptake and in situ remediation study in a ridge-and-furrow area used for the disposal of pink water at the Joliet Army Ammunition Plant
Conceptual design of an emergency tritium clean-up system
International Nuclear Information System (INIS)
Muller, M.E.
1978-01-01
The Los Alamos Scientific Laboratory (LASL) has been selected to design, build, and operate a facility to demonstrate the operability of the tritium-related subsystems that would be required to successfully develop fusion reactor systems. Basically, these subsystems would consist of the deuterium-tritium fuel cycle and associated environmental control systems. An emergency tritium clean-up subsystem (ETC) for this facility will be designed to remove tritium from the cell atmosphere if an accident causes the primary and secondary tritium containment to be breached. Conceptually, the ETC will process cell air at the rate of 0.65 actual m 3 /s (1385 ACFM) and will achieve an overall decontamination factor of 10 6 for tritium oxide (T 2 O). Following the maximum credible release of 100 g of tritium, the ETC will restore the cell to operational status within 24 h without a significant release of tritium to the environment. The basic process will include compression of the air to 0.35 MPa (3.5 atm) in a reciprocating compressor followed by oxidation of the tritium to T 2 O in a catalytic reactor. The air will be cooled to 275 K (350 0 F) to remove most of the moisture, including T 2 O, as a condensate. The remaining moisture will be removed by molecular sieve dryer beds that incorporate a water-swamping step between beds, allowing greater T 2 O removal. A portion of the detritiated air will be recirculated to the cell; the remainder will be exhausted to the building ventilation stack to maintain a slight negative pressure in the cell. The ETC will be designed for maximum flexibility so that studies can be performed that involve various aspects of room air detritiation
Cleaning up the sea bed in the North Sea. 1994
International Nuclear Information System (INIS)
1995-01-01
The yearly raid was executed in an efficient way and without excess technical equipment interruptions. The vessel ''Lance'' owned by the Norwegian Sea Mapping Authorities which was used for the sonar mapping of the sea bed, was equipped with a Klein 531T side seeking sonar, a Simrad echo sounder of the type EM100 (multiray) and differential GPS navigation system. The executive committee has earlier expressed desire for a strengthening of the co-operation with the Norwegian Sea Mapping Authorities. The use of the vessel was in accordance with this wish. Stolt Comex Seaway A/S used the vessel M/S ''Seaway Commander'' and the underwater vessel ''Solo'' for the cleaning up project. The systems worked satisfactory during the entire operation. The cleaning operation was in 1994 carried out in 2 sections. The Petroleum Directorate agreed to letting the M/S ''Seaway Commander'' complete the project for Norsk Hydro at the Troll field in order to avoid delays in the Troll Oil project. In both periods there were good weather conditions. There was no extensive discontinuations due to the weather. During the two periods of 13,5 days 259 out of 370 positions were investigated visually through the systems. This is in average about 20 inspected positions a day. The reason for the high average is that the sailing distances are short between the positions and the findings corresponded to stated positions and sonar interpretations. Also this year there was installed a side seeking sonar in the underwater vessel which resulted in reduced investigation time at each aim. It was possible with this type of sonar to identify the goal quicker and to seek during transit between goals at moderate distances. Few articles with certainty contributed by the petroleum activities were retrieved
Using Phytoremediation to Clean Up Contamination at Military Installations
Energy Technology Data Exchange (ETDEWEB)
Zellmer, S.D.; Hinchman, R.R.; Negri, M.C.; Schneider, J.F. [Argonne National Lab., IL (United States); Gatliff, E.G. [Applied Natural Sciences, Inc., Fairfield, OH (United States)
1997-07-01
During and following World War II, wastes from the production of munitions and other military materials were disposed of using the best available practices acceptable at that time. However, these disposal methods often contaminated soil and groundwater with organic compounds and metals that require cleanup under current regulations. An emerging technology for cleaning contaminated soils and shallow groundwater is phytoremediation, an environmentally friendly, low- cost, and low-tech process. Phytoremediation encompasses all plant- influenced biological, chemical, and physical processes that aid in the uptake, degradation, and metabolism of contaminants by either plants or free-living organisms in the plant`s rhizosphere. A phytoremediation system can be viewed as a biological, solar-driven, pump-and-treat system with an extensive, self-extending uptake network (the root system) that enhances the soil and below-ground ecosystem for subsequent productive use. Argonne National Laboratory (ANL) has been conducting basic and applied research in phytoremediation since 1990. Initial greenhouse studies evaluated salt-tolerant wetland plants to clean UP and reduce the volume of salty `produced water` from petroleum wells. Results of these studies were used to design a bioreactor for processing produced water that is being demonstrated at a natural gas well in Oklahoma; this system can reduce produced water volume by about 75% in less than eight days, representing substantial savings in waste disposal cost. During 1994, ANL conducted a TNT plant uptake and in situ remediation study in a ridge-and-furrow area used for the disposal of pink water at the Joliet Army Ammunition Plant.
Quasi-periodic solutions of nonlinear beam equations with quintic quasi-periodic nonlinearities
Directory of Open Access Journals (Sweden)
Qiuju Tuo
2015-01-01
Full Text Available In this article, we consider the one-dimensional nonlinear beam equations with quasi-periodic quintic nonlinearities $$ u_{tt}+u_{xxxx}+(B+ \\varepsilon\\phi(tu^5=0 $$ under periodic boundary conditions, where B is a positive constant, $\\varepsilon$ is a small positive parameter, $\\phi(t$ is a real analytic quasi-periodic function in t with frequency vector $\\omega=(\\omega_1,\\omega_2,\\dots,\\omega_m$. It is proved that the above equation admits many quasi-periodic solutions by KAM theory and partial Birkhoff normal form.
Nonlinear coherent beam-beam oscillations in the rigid bunch model
International Nuclear Information System (INIS)
Dikansky, N.; Pestrikov, D.
1990-01-01
Within the framework of the rigid bunch model coherent oscillations of strong-strong colliding bunches are described by equations which are specific for the weak-strong beam case. In this paper some predictions of the model for properties of nonlinear coherent oscillations as well as for associated limitations of the luminosity are discussed. 14 refs.; 6 figs
NONLINEAR EVOLUTION OF BEAM-PLASMA INSTABILITY IN INHOMOGENEOUS MEDIUM
International Nuclear Information System (INIS)
Ziebell, L. F.; Pavan, J.; Yoon, P. H.; Gaelzer, R.
2011-01-01
The problem of electron-beam propagation in inhomogeneous solar wind is intimately related to the solar type II and/or type III radio bursts. Many scientists have addressed this issue in the past by means of quasi-linear theory, but in order to fully characterize the nonlinear dynamics, one must employ weak-turbulence theory. Available numerical solutions of the weak-turbulence theory either rely on only one nonlinear process (either decay or scattering), or when both nonlinear terms are included, the inhomogeneity effect is generally ignored. The present paper reports the full solution of weak-turbulence theory that includes both decay and scattering processes, and also incorporating the effects of density gradient. It is found that the quasi-linear effect sufficiently accounts for the primary Langmuir waves, but to properly characterize the back-scattered Langmuir wave, which is important for eventual radiation generation, it is found that both nonlinear decay and scattering processes make comparable contributions. Such a finding may be important in the quantitative analysis of the plasma emission process with application to solar type II and/or type III radio bursts.
Global dynamics and control of a comprehensive nonlinear beam equation
International Nuclear Information System (INIS)
You Yuncheng; Taboada, M.
1994-01-01
A nonlinear hinged extensible elastic beam equation with the structural damping and Balakrishnan-Taylor damping of full exponent is studied as a general model for large space structures. It is proved that there exists an absorbing set in the energy space and that there exist inertial manifolds whose exponential attracting rates however are nonuniform. The control spillover problem associated with the stabilization of this equation is resolved by constructing a linear finite-dimensional feedback control based on the existence of inertial manifolds of the uncontrolled equation. Moreover, the results obtained are robust with respect to uncertainty in the structural parameters. (author). 5 refs
Nonlinear behaviors of a bounded electron beam-plasma system
International Nuclear Information System (INIS)
Iizuka, Satoru; Saeki, Koichi; Sato, Noriyoshi; Hatta, Yoshisuke
1985-01-01
Nonlinear developments of a bounded electron beam-plasma system including stationary electrons are investigated experimentally. A stable double layer is formed as a result of ion trapping in a growing negative potential dip induced by the Pierce instability above the current regime of the Buneman instability. In the in-between regime of the Buneman and Pierce instabilities, energetic ions are observed. This effective ion heating is caused by ion detrapping due to double-layer disruption, being consistent with computer simulation. (author)
Lie Algebraic Treatment of Linear and Nonlinear Beam Dynamics
Energy Technology Data Exchange (ETDEWEB)
Alex J. Dragt; Filippo Neri; Govindan Rangarajan; David Douglas; Liam M. Healy; Robert D. Ryne
1988-12-01
The purpose of this paper is to present a summary of new methods, employing Lie algebraic tools, for characterizing beam dynamics in charged-particle optical systems. These methods are applicable to accelerator design, charged-particle beam transport, electron microscopes, and also light optics. The new methods represent the action of each separate element of a compound optical system, including all departures from paraxial optics, by a certain operator. The operators for the various elements can then be concatenated, following well-defined rules, to obtain a resultant operator that characterizes the entire system. This paper deals mostly with accelerator design and charged-particle beam transport. The application of Lie algebraic methods to light optics and electron microscopes is described elsewhere (1, see also 44). To keep its scope within reasonable bounds, they restrict their treatment of accelerator design and charged-particle beam transport primarily to the use of Lie algebraic methods for the description of particle orbits in terms of transfer maps. There are other Lie algebraic or related approaches to accelerator problems that the reader may find of interest (2). For a general discussion of linear and nonlinear problems in accelerator physics see (3).
Advances in nonlinear vibration analysis of structures. Part-I. Beams
Indian Academy of Sciences (India)
Unknown
element analysis of nonlinear beams under static and dynamic loads. ... linearization, substitution of inplane boundary conditions at element level rather .... Modelling the nonlinear vibration problems using finite elements, albeit with a couple.
Status of Pesticides and Degradation Products in Soil After Clean-up ...
African Journals Online (AJOL)
The status of pesticide residues in soil samples collected from a former storage site one year after clean-up of stockpiles and treatment with NaOH was investigated. The analytes were extracted from samples by pressurized fluid extraction using n-hexane:acetone (75:25) mixture. Clean-up of extracts was conducted by ...
Beam-beam interaction and Pacman effects in the SSC with random nonlinear multipoles
International Nuclear Information System (INIS)
Goderre, G.P.; Ohnuma, S.
1988-01-01
In order to find the combined effects of beam-beam interaction (head-on and long-range) and random nonlinear multipoles in dipole magnets, transverse tunes and smears have been calculated as a function of oscillation amplitudes. Two types of particles, ''regular'' and ''Pacman,'' have been investigated using a modified version of tracking code TEAPOT. Regular particles experience beam-beam interactions in all four interaction regions (IR's), both head-on and long range, while pacman particles interact with bunches of the other beam in one medium-beta and one low-beta IR's only. The model for the beam-beam interaction is of weak-strong type and the strong beam is assumed to have a round Gaussian charge distribution. Furthermore, it is assumed that the vertical closed orbit deviation arising from the finite crossing angle of 70 μrad is perfectly compensated for regular particles. The same compensation applied to pacman particles creates a closed orbit distortion. Linear tunes are adjusted for regular particles to the design values but there are no nonlinear corrections except for chromaticity correcting sextupoles in two families. Results obtained in this study do not show any reduction of dynamic or linear aperture for pacman particles but some doubts exist regarding the validity of defining the linear aperture from the smear alone. Preliminary results are given for regular particles when (Δp/p) is modulated by the synchrotron oscillation. For these, fifty oscillations corresponding to 26,350 revolutions have been tracked. A very slow increase in the horizontal amplitude, /approximately/4 /times/ 10/sup /minus/4//oscillation (relative), is a possibility but this should be confirmed by trackings of larger number of revolutions. 11 refs., 18 figs., 2 tabs
Natural Frequencies and Mode Shapes of a Nonlinear, Uniform Cantilevered Beam
National Research Council Canada - National Science Library
Marquez-Chisolm, Daniel J
2006-01-01
A series of experiments in 1975, referred to as the Princeton Beam Experiments, were performed to measure natural frequencies and create a nonlinear elastic deformation model to improve helicopter main beam designs...
Theoretical and experimental nonlinear dynamics of a clamped-clamped beam MEMS resonator
Mestrom, R.M.C.; Fey, R.H.B.; Nijmeijer, H.
2008-01-01
Microelectromechanical resonators feature nonlineardynamic responses. A first-principles based modeling approach is proposed for a clamped-clamped beam resonator. Starting from the partial differential equation for the beam including geometric and electrostatic nonlinear effects, a reduced-order
Nonlinear dynamics for charges particle beams with a curved axis in the matrix - recursive model
Energy Technology Data Exchange (ETDEWEB)
Dymnikov, A D [University of St Petersburg, (Russian Federation). Institute of Computational Mathematics and Control Process
1994-12-31
In this paper a new matrix and recursive approach has been outlined for treating nonlinear optics of charged particle beams. This approach is a new analytical and computational tool for designers of optimal beam control systems. 9 refs.
Nonlinear dynamics for charges particle beams with a curved axis in the matrix - recursive model
Energy Technology Data Exchange (ETDEWEB)
Dymnikov, A.D. [University of St Petersburg, (Russian Federation). Institute of Computational Mathematics and Control Process
1993-12-31
In this paper a new matrix and recursive approach has been outlined for treating nonlinear optics of charged particle beams. This approach is a new analytical and computational tool for designers of optimal beam control systems. 9 refs.
Nonlinear dynamics for charges particle beams with a curved axis in the matrix - recursive model
International Nuclear Information System (INIS)
Dymnikov, A.D.
1993-01-01
In this paper a new matrix and recursive approach has been outlined for treating nonlinear optics of charged particle beams. This approach is a new analytical and computational tool for designers of optimal beam control systems. 9 refs
Nonlinear saturation controller for vibration supersession of a nonlinear composite beam
Energy Technology Data Exchange (ETDEWEB)
Hamed, Y. S. [Menofia University, Menouf (Egypt); Amer, Y. A. [Zagazig University, Zagazig (Egypt)
2014-08-15
In this paper, a study for nonlinear saturation controller (NSC) is presented that used to suppress the vibration amplitude of a structural dynamic model simulating nonlinear composite beam at simultaneous sub-harmonic and internal resonance excitation. The absorber exploits the saturation phenomenon that is known to occur in dynamical systems with quadratic non-linearities of the feedback gain and a two-to-one internal resonance. The analytical solution for the system and the nonlinear saturation controller are obtained using method of multiple time scales perturbation up to the second order approximation. All possible resonance cases were extracted at this approximation order and studied numerically. The stability of the system at the worst resonance case (Ω = 2ω{sub s} and ω{sub s} =2ω{sub C}) is investigated using both frequency response equations and phase-plane trajectories. The effects of different parameters on the system and the controller are studied numerically. The effect of some types of controller on the system is investigated numerically. The simulation results are achieved using Matlab and Maple programs.
Nonlinear discrete-time multirate adaptive control of non-linear vibrations of smart beams
Georgiou, Georgios; Foutsitzi, Georgia A.; Stavroulakis, Georgios E.
2018-06-01
The nonlinear adaptive digital control of a smart piezoelectric beam is considered. It is shown that in the case of a sampled-data context, a multirate control strategy provides an appropriate framework in order to achieve vibration regulation, ensuring the stability of the whole control system. Under parametric uncertainties in the model parameters (damping ratios, frequencies, levels of non linearities and cross coupling, control input parameters), the scheme is completed with an adaptation law deduced from hyperstability concepts. This results in the asymptotic satisfaction of the control objectives at the sampling instants. Simulation results are presented.
Hamilton, Mark F.
1990-12-01
This report discusses five projects all of which involve basic theoretical research in nonlinear acoustics: (1) pulsed finite amplitude sound beams are studied with a recently developed time domain computer algorithm that solves the KZK nonlinear parabolic wave equation; (2) nonlinear acoustic wave propagation in a liquid layer is a study of harmonic generation and acoustic soliton information in a liquid between a rigid and a free surface; (3) nonlinear effects in asymmetric cylindrical sound beams is a study of source asymmetries and scattering of sound by sound at high intensity; (4) effects of absorption on the interaction of sound beams is a completed study of the role of absorption in second harmonic generation and scattering of sound by sound; and (5) parametric receiving arrays is a completed study of parametric reception in a reverberant environment.
Nonlinear features of the energy beam-driven instability
International Nuclear Information System (INIS)
Lesur, M.; Idomura, Y.; Garbet, X.
2009-01-01
Full text: A concern with ignited fusion plasmas is that, as a result of the instabilities they trigger, the high-energy particles eject themselves before they could give their energy to the core to sustain the reaction. Similarities between this class of instabilities and the so-called Berk-Breizman problem motivate us to study a single-mode instability driven by an energetic particle beam. For this purpose, a one dimensional Vlasov simulation is extended to include a Krook collision operator and external damping processes. The code is benchmarked with previous work. The fully nonlinear behavior is recovered in the whole parameter space characterized by an effective relaxation rate ν a and an external damping rate γ d . Steady state, periodic and chaotic behaviors are observed in nonlinear solutions. In the regime above marginal stability where both ν a and γ d are smaller than the linear drive γ L , we observe a good agreement of steady saturation levels between the simulation and theory. Near marginal stability, the role of the normalized relaxation rate ν a /(γ L -γ d ), which is a key parameter to predict the behavior of the solution, is investigated for an initial distribution with relatively small γ L , which correspond to the situation considered in the theory. In the low relaxation rate regime, frequency sweeping events are observed, and the time-evolution of such event is investigated. (author)
Effectiveness of clean-up procedures on stain susceptibility of different orthodontic adhesives
Directory of Open Access Journals (Sweden)
Swati Pundlik Mane
2014-01-01
Conclusion: Chemical-cure adhesive showed higher stain susceptibility than light-cure adhesive in all clean-up procedures. Both adhesives would show less stain susceptibility with polishing step with rubber cup and pumice.
Cheong, Hae-Kwan; Ha, Mina; Lee, Jong Seong; Kwon, Hojang; Ha, Eun-Hee; Hong, Yun-Chul; Choi, Yeyong; Jeong, Woo-Chul; Hur, Jongil; Lee, Seung-Min; Kim, Eun-Jung; Im, Hosub
2011-01-01
Objectives This study was conducted to examine the relationship between crude oil exposure and physical symptoms among residents participating in clean-up work associated with the Hebei Spirit oil spill, 2007 in Korea. Methods A total of 288 residents responded to a questionnaire regarding subjective physical symptoms, sociodemographic characteristics and clean-up activities that occurred between two and eight weeks after the accident. Additionally, the urine of 154 of the respondents was ana...
Attitudes toward managing hazardous waste: What should be cleaned up and who should pay for it?
International Nuclear Information System (INIS)
Baron, J.; Kunreuther, H.; Gowda, R.
1993-01-01
Hazardous waste policy in the United States uses a liability-based approach, including strict, retroactive, and joint and several liability. To assess attitudes toward these basic principles of liability, and toward priorities for clean-up of wastes, a questionnaire was mailed to legislators, judges, executives of oil and chemical companies, environmentalists, and economists. The questionnaire consisted of abstract, simplified cases, which contrasted basic principles rather than dealing with real-world scenarios. Subjects were asked how they would allocate clean-up costs between companies and government as a function of such factors as adherence to standards, adoption of best available technology (BAT), and influence of penalties on future behavior. Most subjects felt that, if the company followed government standards or used the best available technology (BAT), it should pay for only a portion of the clean-up cost, with the government paying the rest. In general, responses did not support the principles underlying current law - strict, retroactive, and joint-and-several liability. Most subjects were more interested in polluters paying for damages than in deterrence or future benefit - even to the extent that they would have 'harmless' waste sites cleaned up. A bias was found toward complete clean-up of some sites, or 'zero risk.' Different groups of subjects gave similar answers, although more committed environmentalists were more willing to make companies pay and to clean up waste regardless of the cost. 21 refs., 3 tabs
Hamilton, Mark F.
1989-08-01
Four projects are discussed in this annual summary report, all of which involve basic research in nonlinear acoustics: Scattering of Sound by Sound, a theoretical study of two nonconlinear Gaussian beams which interact to produce sum and difference frequency sound; Parametric Receiving Arrays, a theoretical study of parametric reception in a reverberant environment; Nonlinear Effects in Asymmetric Sound Beams, a numerical study of two dimensional finite amplitude sound fields; and Pulsed Finite Amplitude Sound Beams, a numerical time domain solution of the KZK equation.
International Nuclear Information System (INIS)
Davidson, Ronald C.; Lee, W. Wei-li; Hong Qin; Startsev, Edward
2001-01-01
This paper develops a clear procedure for solving the nonlinear Vlasov-Maxwell equations for a one-component intense charged particle beam or finite-length charge bunch propagating through a cylindrical conducting pipe (radius r = r(subscript)w = const.), and confined by an applied focusing force. In particular, the nonlinear Vlasov-Maxwell equations are Lorentz-transformed to the beam frame ('primed' variables) moving with axial velocity relative to the laboratory. In the beam frame, the particle motions are nonrelativistic for the applications of practical interest, already a major simplification. Then, in the beam frame, we make the electrostatic approximation which fully incorporates beam space-charge effects, but neglects any fast electromagnetic processes with transverse polarization (e.g., light waves). The resulting Vlasov-Maxwell equations are then Lorentz-transformed back to the laboratory frame, and properties of the self-generated fields and resulting nonlinear Vlasov-Maxwell equations in the laboratory frame are discussed
AUTHOR|(CDS)2160109; Støvneng, Jon Andreas
2017-08-15
The performance of high-energy circular hadron colliders, as the Large Hadron Collider, is limited by beam-beam interactions. The strength of the beam-beam interactions will be higher after the upgrade to the High-Luminosity Large Hadron Collider, and also in the next generation of machines, as the Future Circular Hadron Collider. The strongly nonlinear force between the two opposing beams causes diverging Hamiltonians and drives resonances, which can lead to a reduction of the lifetime of the beams. The nonlinearity makes the effect of the force difficult to study analytically, even at first order. Numerical models are therefore needed to evaluate the overall effect of different configurations of the machines. For this thesis, a new code named CABIN (Cuda-Accelerated Beam-beam Interaction) has been developed to study the limitations caused by the impact of strong beam-beam interactions. In particular, the evolution of the beam emittance and beam intensity has been monitored to study the impact quantitatively...
Nonlinear beam dynamics of accelerators and storage rings. Progress report, June 1985-April 1986
International Nuclear Information System (INIS)
Helleman, R.H.G.
1986-01-01
Research has concentrated on the stability problems and resonances involved in the two-dimensional beam-beam effect. Of course, the results are applicable also to coupled nonlinear two-dimensional (x,y) accelerator lattices. From a nonlinear dynamics point of view this means that we investigated how to extend existing methods that worked satisfactorily for the one-dimensional beam-beam effect to the higher dimensional world of two-dimensional nonlinear lattices. This requires study of four coupled nonlinear lattice equations (for x, y, p/sub x/,p/sub y/), i.e., study of four-dimensional conservative nonlinear maps. Until our investigation this year, such maps had not yet been studied in nonlinear dynamics. One of the main results is the conclusion that the very successful ''residue'' method to determine stability (of whole regions of orbits) for the one-dimensional beam-beam effect cannot, in its present form, be used for the two- or three-dimensional case. The second main result is that we have been successful in demonstrating and unraveling the complete Period Doubling structure of the resonances in these four-dimensional maps (two-dimensional beam-beam effect), including the most minute resonances. This is essential for an understanding of such maps. In addition, it is the ''self-similarity'' of these resonances which inspires, and guides, most of our efforts in redesigning the residue criterion mentioned above
Mathematical and Numerical Methods for Non-linear Beam Dynamics
International Nuclear Information System (INIS)
Herr, W
2014-01-01
Non-linear effects in accelerator physics are important for both successful operation of accelerators and during the design stage. Since both of these aspects are closely related, they will be treated together in this overview. Some of the most important aspects are well described by methods established in other areas of physics and mathematics. The treatment will be focused on the problems in accelerators used for particle physics experiments. Although the main emphasis will be on accelerator physics issues, some of the aspects of more general interest will be discussed. In particular, we demonstrate that in recent years a framework has been built to handle the complex problems in a consistent form, technically superior and conceptually simpler than the traditional techniques. The need to understand the stability of particle beams has substantially contributed to the development of new techniques and is an important source of examples which can be verified experimentally. Unfortunately, the documentation of these developments is often poor or even unpublished, in many cases only available as lectures or conference proceedings
Observation of Nonlinear Self-Trapping of Broad Beams in Defocusing Waveguide Arrays
International Nuclear Information System (INIS)
Bennet, Francis H.; Haslinger, Franz; Neshev, Dragomir N.; Kivshar, Yuri S.; Alexander, Tristram J.; Mitchell, Arnan
2011-01-01
We demonstrate experimentally the localization of broad optical beams in periodic arrays of optical waveguides with defocusing nonlinearity. This observation in optics is linked to nonlinear self-trapping of Bose-Einstein-condensed atoms in stationary periodic potentials being associated with the generation of truncated nonlinear Bloch states, existing in the gaps of the linear transmission spectrum. We reveal that unlike gap solitons, these novel localized states can have an arbitrary width defined solely by the size of the input beam while independent of nonlinearity.
Development of a matrix approach to estimate soil clean-up levels for BTEX compounds
International Nuclear Information System (INIS)
Erbas-White, I.; San Juan, C.
1993-01-01
A draft state-of-the-art matrix approach has been developed for the State of Washington to estimate clean-up levels for benzene, toluene, ethylbenzene and xylene (BTEX) in deep soils based on an endangerment approach to groundwater. Derived soil clean-up levels are estimated using a combination of two computer models, MULTIMED and VLEACH. The matrix uses a simple scoring system that is used to assign a score at a given site based on the parameters such as depth to groundwater, mean annual precipitation, type of soil, distance to potential groundwater receptor and the volume of contaminated soil. The total score is then used to obtain a soil clean-up level from a table. The general approach used involves the utilization of computer models to back-calculate soil contaminant levels in the vadose zone that would create that particular contaminant concentration in groundwater at a given receptor. This usually takes a few iterations of trial runs to estimate the clean-up levels since the models use the soil clean-up levels as ''input'' and the groundwater levels as ''output.'' The selected contaminant levels in groundwater are Model Toxic control Act (MTCA) values used in the State of Washington
Nonlinear Phenomena in the Single-Mode Dynamics in an AFM Cantilever Beam
Ruzziconi, Laura; Lenci, Stefano; Younis, Mohammad I.
2016-01-01
This study deals with the nonlinear dynamics arising in an atomic force microscope cantilever beam. After analyzing the static behavior, a single degree of freedom Galerkin reduced order model is introduced, which describes the overall scenario
Nonlinear δf Simulation Studies of Intense Charged Particle Beams with Large Temperature Anisotropy
International Nuclear Information System (INIS)
Startsev, Edward A.; Davidson, Ronald C.; Qin, Hong
2002-01-01
In this paper, a 3-D nonlinear perturbative particle simulation code (BEST) [H. Qin, R.C. Davidson and W.W. Lee, Physical Review Special Topics on Accelerators and Beams 3 (2000) 084401] is used to systematically study the stability properties of intense nonneutral charged particle beams with large temperature anisotropy (T perpendicularb >> T parallelb ). The most unstable modes are identified, and their eigenfrequencies, radial mode structure, and nonlinear dynamics are determined for axisymmetric perturbations with ∂/∂θ = 0
Glufosinate ammonium clean-up procedure from water samples using SPE
Tayeb M., A.; Ismail B., S.; Mardiana-Jansar, K.; Ta, Goh Choo; Agustar, Hani Kartini
2015-09-01
For the determination of glufosinate ammonium residue in soil and water samples, different solid phase extraction (SPE) sorbent efficiency was studied. Four different SPE sorbents i.e.: CROMABOND PS-H+, CROMABOND PS-OH-, ISOLUTE ENV+, Water Sep-Pak and OASIS HLB were used. Sample clean-up performance was evaluated using high performance liquid chromatography (Agilent 1220 infinity LC) with fluorescence detector. Detection of FMO-derivatives was done at λ ex = 260 nm and λ em= 310 nm. OASIS HLB column was the most suitable for the clean-up in view of the overall feasibility of the analysis.
Basis of the detection, assessment and cleaning up of sites contaminated with heavy metals
International Nuclear Information System (INIS)
Calmano, W.; Foerstner, U.
1993-01-01
The cleaning up of sites contaminated with heavy metals is still in its infancy. Depending on the type and extent of the contamination, new methods of treatment must be developed and matched to each situation. A survey is given of the groundwater contamination of soil heavy metals; the binding, availability and mobilisation of heavy metals; geo-chemical concepts for sites contaminated by heavy metals; judging the potential danger; safety measures; cleaning up processes and the reinstatement and renaturing of the soil. (orig.) [de
Data clean-up and management a practical guide for librarians
Hogarth, Margaret
2012-01-01
Data use in the library has specific characteristics and common problems. Data Clean-up and Management addresses these, and provides methods to clean up frequently-occurring data problems using readily-available applications. The authors highlight the importance and methods of data analysis and presentation, and offer guidelines and recommendations for a data quality policy. The book gives step-by-step how-to directions for common dirty data issues.focused towards libraries and practicing librariansdeals with practical, real-life issues and addresses common problems that all libraries faceoffe
Dyscirculatory encephalopathy in Chernobyl disaster clean-up workers (a 20-year study).
Podsonnaya, I V; Shumakher, G I; Golovin, V A
2010-05-01
Results obtained over 20-years of following 536 Chernobyl clean-up workers and 436 control subjects are presented. Dyscirculatory encephalopathy developed more frequently in persons exposed to radiation at age 30 years. As compared with the control group, workers were characterized by early onset of disease, faster progression, stable symptomatology for 5-6 years, and further progression of disease in the form of autonomic dysfunction, psycho-organic syndrome, and epilepsy. Major strokes were also more common in clean-up workers.
Directory of Open Access Journals (Sweden)
Şeref Doğuşcan Akbaş
2013-01-01
Full Text Available Geometrically nonlinear static analysis of edge cracked cantilever Timoshenko beams composed of functionally graded material (FGM subjected to a nonfollower transversal point load at the free end of the beam is studied with large displacements and large rotations. Material properties of the beam change in the height direction according to exponential distributions. The cracked beam is modeled as an assembly of two subbeams connected through a massless elastic rotational spring. In the study, the finite element of the beam is constructed by using the total Lagrangian Timoshenko beam element approximation. The nonlinear problem is solved by using incremental displacement-based finite element method in conjunction with Newton-Raphson iteration method. The convergence study is performed for various numbers of finite elements. In the study, the effects of the location of crack, the depth of the crack, and various material distributions on the nonlinear static response of the FGM beam are investigated in detail. Also, the difference between the geometrically linear and nonlinear analysis of edge cracked FGM beam is investigated in detail.
Nonlinear interaction of strong microwave beam with the ionosphere MINIX rocket experiment
Energy Technology Data Exchange (ETDEWEB)
Kaya, N.; Matsumoto, H.; Miyatake, S.; Kimura, I.; Nagatomo, M.; Obayashi, T.
1986-01-01
A rocket-borne experiment called MINIX was carried out to investigate the nonlinear interaction of a strong microwave energy beam with the ionosphere. The MINIX stands for Microwave-Ionosphere Nonlinear Interaction Experiment and was carried out on August 29, 1983. The objectives of the MINIX is to study possible impacts of the SPS microwave energy beam on the ionosphere such as the Ohmic heating and plasma wave excitation. The experiment showed that the microwave with f = 2.45 GHz nonlinearly excites various electrostatic plasma waves, though no Ohmic heating effects were detected. 4 figures.
Nonlinear interaction of strong microwave beam with the ionosphere MINIX rocket experiment
Kaya, N.; Matsumoto, H.; Miyatake, S.; Kimura, I.; Nagatomo, M.
A rocket-borne experiment called 'MINIX' was carried out to investigate the nonlinear interaction of a strong microwave energy beam with the ionosphere. The MINIX stands for Microwave-Ionosphere Nonlinear Interaction eXperiment and was carried out on August 29, 1983. The objective of the MINIX is to study possible impacts of the SPS microwave energy beam on the ionosphere, such as the ohmic heating and plasma wave excitation. The experiment showed that the microwave with f = 2.45 GHz nonlinearly excites various electrostatic plasma waves, though no ohmic heating effects were detected.
Nonlinear interaction of strong microwave beam with the ionosphere MINIX rocket experiment
International Nuclear Information System (INIS)
Kaya, N.; Matsumoto, H.; Miyatake, S.; Kimura, I.; Nagatomo, M.; Obayashi, T.
1986-01-01
A rocket-borne experiment called MINIX was carried out to investigate the nonlinear interaction of a strong microwave energy beam with the ionosphere. The MINIX stands for Microwave-Ionosphere Nonlinear Interaction Experiment and was carried out on August 29, 1983. The objectives of the MINIX is to study possible impacts of the SPS microwave energy beam on the ionosphere such as the Ohmic heating and plasma wave excitation. The experiment showed that the microwave with f = 2.45 GHz nonlinearly excites various electrostatic plasma waves, though no Ohmic heating effects were detected. 4 figures
Determination of the viability of chicken feather as oil spill clean-up ...
African Journals Online (AJOL)
In this study a comparative assessment was conducted between chicken feather and a conventional synthetic sorbent mat used in the oil industry to clean-up oil spill. The result of the study shows that chicken feather has higher oil sorption capacity and sorbed oil recoverability than the standard (synthetic sorbent mat), and ...
Determination of fusaric acid in maize using molecularly imprinted SPE clean-up
A new liquid chromatography method to detect fusaric acid in maize is reported based on molecularly imprinted polymer solid phase extraction clean-up (MISPE) using mimic-templated molecularly-imprinted polymers. Picolinic acid was used as a toxin analog for imprinting polymers during a thermolytic s...
Status of Pesticides and Degradation Products in Soil After Clean up
African Journals Online (AJOL)
dell
The status of pesticide residues in soil samples collected from a former storage site one year after clean-up ... risk to the underground water (Felsot et al. ... the properties of the contaminants, soil .... and isotope ratios for the labelled standards.
Latvian Chernobyl clean-up workers dynamics of morbidity 15 years of the post radiation period
International Nuclear Information System (INIS)
Zvagule, T.; Eglite, M.; Bruvere, R.; Gabruseva, N.; Feldmane, G.
2003-01-01
Nearly 1.0% of the male population of Latvia were sent (1986-1991) to Chernobyl to assist in the clean-up activities after the nuclear power plant accident (1986). The prevalence of all types of diseases, dynamic of breaking out of the key symptoms and interferon status were evaluated in respect to date of work, duration of work and kind of work in the whole clean-up workers group and in the particular group with seizures of unconsciousness. The disease incidence in clean-up workers from Latvia exceeds that observed in age and sex matched male population. Most had several diseases each and their poly-symptomatic sicknesses exhibited tendency to progress even 10-14 years after the exposure (during 1996-2000). Diseases of nervous, digestive and circulatory system, mental disorders and diseases of muscles and connective tissue were the most frequent. The primary outset of symptoms being low in the first 2-3 years after the work gradually increased during the following 10 years. Leukopenia was predominant in 1990-1993 and leucocytosis in 1997-2000. Ability of leukocytes to produce interferons was significantly decreased. Since the external radiation doses did not exceed 50 centyGy (cGy) there is sufficient reasons to believe that the principal cause of the gradually increased frequency of health problems is the long-life radioisotopes incorporated in the clean-up workers bodies as permanent radiation and toxic compounds source. (authors)
Case Study: Using Microbe Molecular Biology for Gulf Oil Spill Clean Up
Jones, Daniel R.
2011-01-01
This case has the student actively investigate the regulation of expression of a novel bacterial gene in the context of attempts to solve a real world problem, clean up of the April 2010 Deep Water Horizon oil spill in the Gulf of Mexico. Although the case is fictitious, it is based on factual gene regulatory characteristics of oil-degrading…
Chromosome aberrations and rogue cells in lymphocytes of Chernobyl clean-up workers
International Nuclear Information System (INIS)
Lazutka, J.R.
1996-01-01
A cytogenetic analysis was performed on peripheral blood lymphocytes from 183 Chernobyl clean-up workers and 27 control individuals. Increased frequencies of chromosome aberrations were associated with exposure to radiation at Chernobyl, alcohol abuse and a history of recent influenza infection. However, only approximately 20% of Chernobyl clean-up workers had an increased frequency of dicentric and ring chromosomes. At the same time, an increased frequency of acentric fragments in lymphocytes of clean-up workers was characteristic. The use of multivitamins as dietary supplement significantly decreased the frequency of chromosome aberrations, especially of chromatid breaks. Rogue cells were found in lymphocytes of 28 clean-up workers and 3 control individuals. The appearance of rogue cells was associated with a recent history of acute respiratory disease (presumably caused by adenoviral infection) and, probably, alcohol abuse. Dicentric chromosomes in rogue cells were distributed according to a negative binomial distribution. Occurrence of rogue cells due to a perturbation of cell cycle control and abnormal apoptosis is suggested
Cheong, Hae-Kwan; Lee, Jong Seong; Kwon, Hojang; Ha, Eun-Hee; Hong, Yun-Chul; Choi, Yeyong; Jeong, Woo-Chul; Hur, Jongil; Lee, Seung-Min; Kim, Eun-Jung; Im, Hosub
2011-01-01
Objectives This study was conducted to examine the relationship between crude oil exposure and physical symptoms among residents participating in clean-up work associated with the Hebei Spirit oil spill, 2007 in Korea. Methods A total of 288 residents responded to a questionnaire regarding subjective physical symptoms, sociodemographic characteristics and clean-up activities that occurred between two and eight weeks after the accident. Additionally, the urine of 154 of the respondents was analyzed for metabolites of volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) and heavy metals. To compare the urinary levels of exposure biomarkers, the urine of 39 inland residents who were not directly exposed to the oil spill were analyzed. Results Residents exposed to oil remnants through clean-up work showed associations between physical symptoms and the exposure levels defined in various ways, including days of work, degree of skin contamination, and levels of some urinary exposure biomarkers of VOCs, metabolites and metals, although no major abnormalities in urinary exposure biomarkers were observed. Conclusions This study provides evidence of a relationship between crude oil exposure and acute human health effects and suggests the need for follow-up to evaluate the exposure status and long-term health effects of clean-up participants. PMID:22125768
A simple numerical model of a geometrically nonlinear Timoshenko beam
Keijdener, C.; Metrikine, A.
2015-01-01
In the original problem for which this model was developed, onedimensional flexible objects interact through a non-linear contact model. Due to the non-linear nature of the contact model, a numerical time-domain approach was adopted. One of the goals was to see if the coupling between axial and
Thyroid Nodularity and cancer in Chernobyl clean-up workers from Latvia
International Nuclear Information System (INIS)
Kurjane, N.; Farbtuha, T.; Matisane, L.
2004-01-01
The Chernobyl nuclear reactor accident on April 26, 1986, resulted in massive radioactive contamination of the surrounding area. Radiation exposure was from rapidly decaying radioactive iodines, as well as from 137 CS and other long-lived radioisotopes. About 6000 clean-up workers of the Chernobyl Power Plant accident were from Latvia. External radiation exposure was defined for 40% of them and the doses were 0.01-0.5 Grey (Gy). Although according to conclusions of authoritative experts of different countries, the actual doses of radiation might be at least 3-4 times higher. Because the thyroid is highly susceptible to cancer induction by ionizing radiation, our examination was conducted in 2001 to determine the prevalence of thyroid tumors in 1990-2000 and other nodular thyroid disease 14 years after the accident in Latvia's Chernobyl clean-up workers. The Latvian State Register for persons who have received ionising radiation in Chernobyl and Latvia's Cancer Register were used in this work as well as 1000 Chernobyl accident clean-up workers medical ambulatory cards were analysed. We have received that occurrence of thyroid cancer in Chernobyl clean-up workers was 10,6 times higher than in Latvia's population (men) in 1990-2000 and also it occurs at earlier age in comparison with population data (40-50 and 55-65 accordingly). This can be explained in two ways: either due to effect of the short-term or long-term external and internal radiation exposure (including, from the incorporated 131 I) on the thyroid tissue, or due to a better dispensarisation (obligatory thyroid ultrasound examination once per year) of the examined group. The first thyroid cancer was discovered in 1996 -after ten years of latent period. The relative risk of thyroid cancer in Chernobyl clean-up workers in 1996 was 33.27, and in 1997 -42.64. Then, the morbidity of the thyroid cancer exhibits tendency to decrease (RR 18.27 in 1998, and 9.42 in 1999). The presence of thyroid benign nodules was
Efficiency of different protocols for enamel clean-up after bracket debonding: an in vitro study
Directory of Open Access Journals (Sweden)
Lara Carvalho Freitas Sigilião
2015-10-01
Full Text Available Objective: This study aimed to assess the efficiency of six protocols for cleaning-up tooth enamel after bracket debonding.Methods:A total of 60 premolars were divided into six groups, according to the tools used for clean-up: 12-blade bur at low speed (G12L, 12-blade bur at high speed (G12H, 30-blade bur at low speed (G30L, DU10CO ORTHO polisher (GDU, Renew System (GR and Diagloss polisher (GD. Mean roughness (Ra and mean roughness depth (Rz of enamel surface were analyzed with a profilometer. Paired t-test was used to assess Ra and Rz before and after enamel clean-up. ANOVA/Tukey tests were used for intergroup comparison. The duration of removal procedures was recorded. The association between time and variation in enamel roughness (∆Ra, ∆Rz were evaluated by Pearson's correlation test. Enamel topography was assessed by scanning electron microscopy (SEM.Results:In Groups G12L and G12H, original enamel roughness did not change significantly. In Groups G30L, GDU, GR and GD, a smoother surface (p < 0.05 was found after clean-up. In Groups G30L and GD, the protocols used were more time-consuming than those used in the other groups. Negative and moderate correlation was observed between time and (∆Ra, ∆Rz; Ra and (∆Ra, ∆Rz; Rz (r = - 0.445, r = - 0.475, p < 0.01.Conclusion:All enamel clean-up protocols were efficient because they did not result in increased surface roughness. The longer the time spent performing the protocol, the lower the surface roughness.
Nonlinear propagation of phase-conjugate focused sound beams in water
Brysev, A. P.; Krutyansky, L. M.; Preobrazhensky, V. L.; Pyl'nov, Yu. V.; Cunningham, K. B.; Hamilton, M. F.
2000-07-01
Nonlinear propagation of phase-conjugate, focused, ultrasound beams is studied. Measurements are presented of harmonic amplitudes along the axis and in the focal plane of the conjugate beam, and of the waveform and spectrum at the focus. A maximum peak pressure of 3.9 MPa was recorded in the conjugate beam. The measurements are compared with simulations based on the KZK equation, and satisfactory agreement is obtained.
Lesina, Antonino Cala'; Berini, Pierre; Ramunno, Lora
2017-02-06
We report on a chiral gap-nanostructure, which we term a "butterfly nanoantenna," that offers full vectorial control over nonlinear emission. The field enhancement in its gap occurs for only one circular polarization but for every incident linear polarization. As the polarization, phase and amplitude of the linear field in the gap are highly controlled, the linear field can drive nonlinear emitters within the gap, which behave as an idealized Huygens source. A general framework is thereby proposed wherein the butterfly nanoantennas can be arranged in a metasurface, and the nonlinear Huygens sources exploited to produce a highly structured far-field optical beam. Nonlinearity allows us to shape the light at shorter wavelengths, not accessible by linear plasmonics, and resulting in high purity beams. The chirality of the butterfly allows us to create orbital angular momentum states using a linearly polarized excitation. A third harmonic Laguerre-Gauss beam carrying an optical orbital angular momentum of 41 is demonstrated as an example, through large-scale simulations on a high-performance computing platform of the full plasmonic metasurface with an area large enough to contain up to 3600 nanoantennas.
International Nuclear Information System (INIS)
Emans, Joseph; Wiercigroch, Marian; Krivtsov, Anton M.
2005-01-01
The nonlinear analysis of a common beam system was performed, and the method for such, outlined and presented. Nonlinear terms for the governing dynamic equations were extracted and the behaviour of the system was investigated. The analysis was carried out with and without physically realistic parameters, to show the characteristics of the system, and the physically realistic responses. Also, the response as part of a more complex system was considered, in order to investigate the cumulative effects of nonlinearities. Chaos, as well as periodic motion was found readily for the physically unrealistic parameters. In addition, nonlinear behaviour such as co-existence of attractors was found even at modest oscillation levels during investigations with realistic parameters. When considered as part of a more complex system with further nonlinearities, comparisons with linear beam theory show the classical approach to be lacking in accuracy of qualitative predictions, even at weak oscillations
Nonlinear dynamic of interaction of the relativistic electron beam with plasma
International Nuclear Information System (INIS)
Dorofeenko, V.G.; Krasovitskii, V.B.; Osmolovsky, S.I.
1994-01-01
Quasi-transverse instability of thin relativistic electron beam in a dense plasma is studied numerically and analytically in a broad range of the frequency of the beam modulation and external longitudinal magnetic field. It is shown that the nonlinear stage of solution depends on the increment of the instability. It is permitted to classify possible nonlinear solutions and also to determine optimal regimes of the modulation for transport of beam along magnetic field in a plasma without substantial radial divergence. Numerical calculations show, that injection of the bunches with parameters, corresponding nonlinear regime of the beam's instability, in neutrally-charged plasma permits to output on the stationary regime without loss of particles
Beam density equalization in a channel with nonlinear optics
International Nuclear Information System (INIS)
Batygin, Yu.K.; Kushin, V.V.; Nesterov, N.A.; Plotnikov, S.V.
1993-01-01
Simulation of beam density equalization in 2.85 m length transport channel covering two quadrupole lenses and two octupole lenses was carried out to obtain irradiation homogeneous field of track membrane materials. 0.3 MeV/nucleon energy and 1/8 electron-charge-mass ratio ion beam was supplied to the system inlet. Equalization of beam density function equal to about 80% was obtained. 4 refs., 1 fig
Hosseini, Seyed Farhad; Hashemian, Ali; Moetakef-Imani, Behnam; Hadidimoud, Saied
2018-03-01
In the present paper, the isogeometric analysis (IGA) of free-form planar curved beams is formulated based on the nonlinear Timoshenko beam theory to investigate the large deformation of beams with variable curvature. Based on the isoparametric concept, the shape functions of the field variables (displacement and rotation) in a finite element analysis are considered to be the same as the non-uniform rational basis spline (NURBS) basis functions defining the geometry. The validity of the presented formulation is tested in five case studies covering a wide range of engineering curved structures including from straight and constant curvature to variable curvature beams. The nonlinear deformation results obtained by the presented method are compared to well-established benchmark examples and also compared to the results of linear and nonlinear finite element analyses. As the nonlinear load-deflection behavior of Timoshenko beams is the main topic of this article, the results strongly show the applicability of the IGA method to the large deformation analysis of free-form curved beams. Finally, it is interesting to notice that, until very recently, the large deformations analysis of free-form Timoshenko curved beams has not been considered in IGA by researchers.
Immune state of patients of vegeto-vascular dystonia, clean-up workers of the Chernobyl accident
International Nuclear Information System (INIS)
Sakhno, T.A.; Davydova, T.I.; Bazika, D.A.; Chumak, A.A.
1995-01-01
Immune state of 272 clean-up workers, participants of the Chernobyl Power Plant accident, suffering from vegeto-vascular dystonia is studied. Comparison groups were formed by 20 healthy clean-up workers, 25 vegeto-vascular dystonia patients non-participating in the clean-up works, and 60 healthy donors. Immune state disturbances in the vegeto-vascular dystonia patients have unidirectional changing but among the clear-up workers their expression was much significant coinciding with the more severe clinical courses of disease comparing to the patients non-participating in the clean-up works
Directory of Open Access Journals (Sweden)
F. Sheykhe
Full Text Available The present paper, compares the effect of the annular and solid electron beam on the efficiency of linear and nonlinear TWTs. To do this, first we introduce four different geometric structure of the beam-helix. Then, we calculate the output power of each structure, in linear and nonlinear modes, at different frequencies using the numerical solution of the mathematical equations of the multi-frequency Eulerian model. Now, plot the output power in terms of distance for each structure at different frequencies and compare them. In a linear tube, the effect of annular beams on the output power is better than the solid beam, while this affects the frequency in nonlinear tubes. It is shown that in linear regime the power increase linearly with frequency but for nonlinear regimes is nonlinear. Keywords: Annular beam, Solid beam, Circuit power, Nonlinear, Traveling wave tube, Helix
Nonlinearities in the response of beam position monitors
International Nuclear Information System (INIS)
Assmann, R.; Dehning, B.; Matheson, J.; Prochnow, J.
2000-01-01
At the LEP e + /e - collider at CERN, Geneva, a Spectrometer is used to determine the beam energy with a relative accuracy of 10 -4 .The Spectrometer measures the change in bending angle in a dipole magnet, the beam trajectory being obtained using beam position monitors (BPMs), which must have an accuracy close to 1 μm in order to achieve the desired precision. The BPMs used feature an aluminum block with an elliptical aperture and capacitive pickup electrodes. The response depends on the electrode geometry and also on the shape of the monitor aperture. In addition, the size of the beam itself contributes if the beam is off-center. The beam size varies according to the beta and dispersion functions at the Spectrometer, so that each BPM may exhibit a systematic shift of the measured beam position. We have investigated the implications of such shifts on the performance of the Spectrometer. We present analytical results, a computer model of the BPM response, and comparison with measurements. The model suggests strategies such as beam-based alignment to minimize the systematic effects arising from the BPMs
International Nuclear Information System (INIS)
Yeh, Y-L; Jang, M-J; Wang, C-C; Lin, Y-P; Chen, K-S
2008-01-01
This paper investigates the nonlinear dynamic response of an atomic force microscope (AFM) cantilever beam tip during the nanolithography of a copper (Cu) surface using a high-depth feed. The dynamic motion of the tip is modeled using a combined approach based on Newton's law and empirical observations. The cutting force is determined from experimental observations of the piling height on the Cu surface and the rotation angle of the cantilever beam tip. It is found that the piling height increases linearly with the cantilever beam carrier velocity. Furthermore, the cantilever beam tip is found to execute a saw tooth motion. Both this motion and the shear cutting force are nonlinear. The elastic modulus in the y direction is variable. Finally, the velocity of the cantilever beam tip as it traverses the specimen surface has a discrete characteristic rather than a smooth, continuous profile
Nonlinear vibrations of an inclined beam subjected to a moving load
International Nuclear Information System (INIS)
Mamandi, A; Kargarnovin, M H; Younesian, D
2009-01-01
In this paper, the nonlinear dynamic responses of an inclined pinned-pinned Euler-Bernoulli beam with a constant cross section and finite length subjected to a concentrated vertical force traveling with constant velocity is investigated by using the mode summation method. Frequency analysis of the PDE's governing equations of motion for steady-state response is studied by applying multiple scales method. The nonlinear dynamic deflections of the beam are obtained by solving two coupled nonlinear PDE's governing equations of planar motion for both longitudinal and transverse oscillations of the beam. The dynamic magnification factor and normalized time histories of mid-point of the beam are obtained for various load velocity ratios and the numerical results are compared with those obtained from traditional linear solution. It is found that quadratic nonlinearity renders the softening effect on the dynamic response of the beam under the act of traveling load. Also stability analysis of the steady-state response for the modes equations having quadratic nonlinearity is carried out and it is observed from the amplitude response curves that for the case of internal-external primary resonance, both saturation phenomenon and jump phenomenon are predicted for the longitudinal excitation.
Nonlinear delta f Simulations of Collective Effects in Intense Charged Particle Beams
Hong Qi
2003-01-01
A nonlinear delta(f) particle simulation method based on the Vlasov-Maxwell equations has been recently developed to study collective processes in high-intensity beams, where space-charge and magnetic self-field effects play a critical role in determining the nonlinear beam dynamics. Implemented in the Beam Equilibrium, Stability and Transport (BEST) code [H. Qin, R.C. Davidson, and W.W. Lee, Physical Review -- Special Topics on Accelerator and Beams 3 (2000) 084401; 3 (2000) 109901.], the nonlinear delta(f) method provides a low-noise and self-consistent tool for simulating collective interactions and nonlinear dynamics of high-intensity beams in modern and next-generation accelerators and storage rings, such as the Spallation Neutron Source and heavy ion fusion drivers. A wide range of linear eigenmodes of high-intensity charged-particle beams can be systematically studied using the BEST code. Simulation results for the electron-proton two-stream instability in the Proton Storage Ring experiment [R. Macek, ...
Directory of Open Access Journals (Sweden)
Huiqing Fang
2016-01-01
Full Text Available Based on geometrically exact beam theory, a hybrid interpolation is proposed for geometric nonlinear spatial Euler-Bernoulli beam elements. First, the Hermitian interpolation of the beam centerline was used for calculating nodal curvatures for two ends. Then, internal curvatures of the beam were interpolated with a second interpolation. At this point, C1 continuity was satisfied and nodal strain measures could be consistently derived from nodal displacement and rotation parameters. The explicit expression of nodal force without integration, as a function of global parameters, was founded by using the hybrid interpolation. Furthermore, the proposed beam element can be degenerated into linear beam element under the condition of small deformation. Objectivity of strain measures and patch tests are also discussed. Finally, four numerical examples are discussed to prove the validity and effectivity of the proposed beam element.
Quasi-ideal dynamics of vortex solitons embedded in flattop nonlinear Bessel beams.
Porras, Miguel A; Ramos, Francisco
2017-09-01
The applications of vortex solitons are severely limited by the diffraction and self-defocusing spreading of the background beam where they are nested. Nonlinear Bessel beams in self-defocusing media are nondiffracting, flattop beams where the nested vortex solitons can survive for propagation distances that are one order of magnitude larger than in the Gaussian or super-Gaussian beams. The dynamics of the vortex solitons is studied numerically and found to approach that in the ideal, uniform background, preventing vortex spiraling and decay, which eases vortex steering for applications.
Directory of Open Access Journals (Sweden)
Shaoheng Wang
2008-05-01
Full Text Available Derbenev proposed producing a high quality flat beam of high-transverse-emittance ratio (HTER with a linear accelerator. Kim also discussed the round-to-flat transformation of angular-momentum-dominated beam. Fermilab/NICADD Photoinjector Laboratory has performed many experiments on HTER beam production. Experiments and simulations, collectively, showed an S-shaped transverse distribution in the flat beam. In this paper, the source of this emittance deterioration in the transformation is identified as the nonlinear rf cavity focusing force; and a solution is proposed.
Epidemiology of non-tumor diseases in Chernobyl clean-up workers
International Nuclear Information System (INIS)
Buzunov, V.A.; Pirogova, E.A.; Tereshchenko, V.M.; Krasnikova, L.I.; Vojchulene, Yu.S.
2004-01-01
Epidemiological study of non-tumor diseases in Chernobyl clean-up workers was effectuated on the materials of State Registry of Ukraine for Victims of Chernobyl NPP Accident. Percent of healthy people among the clean-up workers of 1986 - 1987 decreased from 67.6% in 1988 to 9.6% in 1998, patients with chronic diseases increased from 12,8% in 1988 to 79,1% in 1998. Quantitative risk-analysis proves to possible relationship with absorbed doses prevalences of diseases of blood and hemopoietic organs, coronary hearth disease, cerebrovascular diseases, thyroid pathology. The age at the time of investigation, tobacco smoking and stress were statistically significant non-radiation factors of relative risk
Fuel cycles and fission products clean up for the MOSART concept
Energy Technology Data Exchange (ETDEWEB)
Ignatiev, V. V.; Feynberg, O. S.; Zakirov, R. Y. [Russian Research Center, Kurchatov Institute, Moscow (Russian Federation)
2008-08-15
Analysis of different methods for MOSART fuel salt clean up and experimental results produced within ISTC 1606 permits to make the following conclusions: {center_dot} Fuel salt clean up steps of Li,Be/F MOSART system could be based on the method of reductive extraction in liquid bismuth. {center_dot} Electrodeposition on solid indifferent electrodes (Mo, W) is not effective for separation of actinides and lanthanides in Li,Na,Be/F melt. However, preliminary experiments on electrodeposition on solid non indifferent electrodes (nickel) give foundation to suppose that An/Ln separation on these electrodes could be more effective. In order to determine characteristics of An/Ln electrochemical separation, it is necessary to conduct additional studies in Li,Na,Be/F melt on solid non indifferent electrodes.
Clean-up of the sea bed in the North Sea 1996
International Nuclear Information System (INIS)
1997-01-01
The petroleum activities in the North Sea have inadvertently caused some conflict with fishermen getting their trawls etc. into trash from littering of the sea bed. In the present report, the Norwegian Petroleum Directorate describes a clean-up operation undertaken in 1996 and paid by the State. A clean-up area of 1000 km 2 off Karmoey was selected. This area was mapped by side scan sonar along survey lines 300 m equidistant and a sonar range of 200 m. The sonar data were continuously interpreted by a geophysicist. Selected targets were then identified by ROV and eventually removed. Of the 59 targets examined, 11 were removed and dumped onshore. The largest part elevated was a chain cable of 9 tons. There is also a brief discussion of the compensation agreement with Norwegian fishermen. 4 figs
The use of ultrafiltration for the clean-up of alkaline Pu containing effluents
International Nuclear Information System (INIS)
Biddle, P.; Gutman, R.G.
1983-07-01
Ultrafiltration has been used to clean up low level Pu solutions at high pH. The decontamination factors achieved were greater than 1000 and were significantly higher than those attained by sedimentation or centrifugation. The results confirmed the findings of earlier work based on the use of Th as a simulant for Pu. A preliminary flowsheet for the decontamination of Pu oxalate liquors is proposed. (author)
International Nuclear Information System (INIS)
Sugaya, R.; Ue, A.; Maehara, T.; Sugawa, M.
1996-01-01
Acceleration and heating of a relativistic electron beam by cascading nonlinear Landau damping involving three or four intense electromagnetic waves in a plasma are studied theoretically based on kinetic wave equations and transport equations derived from relativistic Vlasov endash Maxwell equations. Three or four electromagnetic waves excite successively two or three nonresonant beat-wave-driven relativistic electron plasma waves with a phase velocity near the speed of light [v p =c(1-γ -2 p ) 1/2 , γ p =ω/ω pe ]. Three beat waves interact nonlinearly with the electron beam and accelerate it to a highly relativistic energy γ p m e c 2 more effectively than by the usual nonlinear Landau damping of two electromagnetic waves. It is proved that the electron beam can be accelerated to more highly relativistic energy in the plasma whose electron density decreases temporally with an appropriate rate because of the temporal increase of γ p . copyright 1996 American Institute of Physics
An efficient and accurate method for calculating nonlinear diffraction beam fields
Energy Technology Data Exchange (ETDEWEB)
Jeong, Hyun Jo; Cho, Sung Jong; Nam, Ki Woong; Lee, Jang Hyun [Division of Mechanical and Automotive Engineering, Wonkwang University, Iksan (Korea, Republic of)
2016-04-15
This study develops an efficient and accurate method for calculating nonlinear diffraction beam fields propagating in fluids or solids. The Westervelt equation and quasilinear theory, from which the integral solutions for the fundamental and second harmonics can be obtained, are first considered. A computationally efficient method is then developed using a multi-Gaussian beam (MGB) model that easily separates the diffraction effects from the plane wave solution. The MGB models provide accurate beam fields when compared with the integral solutions for a number of transmitter-receiver geometries. These models can also serve as fast, powerful modeling tools for many nonlinear acoustics applications, especially in making diffraction corrections for the nonlinearity parameter determination, because of their computational efficiency and accuracy.
Nonlinear model of a rotating hub-beams structure: Equations of motion
Warminski, Jerzy
2018-01-01
Dynamics of a rotating structure composed of a rigid hub and flexible beams is presented in the paper. A nonlinear model of a beam takes into account bending, extension and nonlinear curvature. The influence of geometric nonlinearity and nonconstant angular velocity on dynamics of the rotating structure is presented. The exact equations of motion and associated boundary conditions are derived on the basis of the Hamilton's principle. The simplification of the exact nonlinear mathematical model is proposed taking into account the second order approximation. The reduced partial differential equations of motion together with associated boundary conditions can be used to study natural or forced vibrations of a rotating structure considering constant or nonconstant angular speed of a rigid hub and an arbitrary number of flexible blades.
Nonlinear features identified by Volterra series for damage detection in a buckled beam
Directory of Open Access Journals (Sweden)
Shiki S. B.
2014-01-01
Full Text Available The present paper proposes a new index for damage detection based on nonlinear features extracted from prediction errors computed by multiple convolutions using the discrete-time Volterra series. A reference Volterra model is identified with data in the healthy condition and used for monitoring the system operating with linear or nonlinear behavior. When the system has some structural change, possibly associated with damage, the index metrics computed could give an alert to separate the linear and nonlinear contributions, besides provide a diagnostic about the structural state. To show the applicability of the method, an experimental test is performed using nonlinear vibration signals measured in a clamped buckled beam subject to different levels of force applied and with simulated damages through discontinuities inserted in the beam surface.
Energy Technology Data Exchange (ETDEWEB)
Jeong, Hyun Jo; Cho, Sung Jong; Nam, Ki Woong; Lee, Jang Hyun [Division of Mechanical and Automotive Engineering, Wonkwang University, Iksan (Korea, Republic of)
2016-04-15
The nonlinearity parameter is frequently measured as a sensitive indicator in damaged material characterization or tissue harmonic imaging. Several previous studies have employed the plane wave solution, and ignored the effects of beam diffraction when measuring the non-linearity parameter β. This paper presents a multi-Gaussian beam approach to explicitly derive diffraction corrections for fundamental and second harmonics under quasilinear and paraxial approximation. Their effects on the nonlinearity parameter estimation demonstrate complicated dependence of β on the transmitter-receiver geometries, frequency, and propagation distance. The diffraction effects on the non-linearity parameter estimation are important even in the nearfield region. Experiments are performed to show that improved β values can be obtained by considering the diffraction effects.
Accelerated solvent extraction method with one-step clean-up for hydrocarbons in soil
International Nuclear Information System (INIS)
Nurul Huda Mamat Ghani; Norashikin Sain; Rozita Osman; Zuraidah Abdullah Munir
2007-01-01
The application of accelerated solvent extraction (ASE) using hexane combined with neutral silica gel and sulfuric acid/ silica gel (SA/ SG) to remove impurities prior to analysis by gas chromatograph with flame ionization detector (GC-FID) was studied. The efficiency of extraction was evaluated based on the three hydrocarbons; dodecane, tetradecane and pentadecane spiked to soil sample. The effect of ASE operating conditions (extraction temperature, extraction pressure, static time) was evaluated and the optimized condition obtained from the study was extraction temperature of 160 degree Celsius, extraction pressure of 2000 psi with 5 minutes static extraction time. The developed ASE with one-step clean-up method was applied in the extraction of hydrocarbons from spiked soil and the amount extracted was comparable to ASE extraction without clean-up step with the advantage of obtaining cleaner extract with reduced interferences. Therefore in the developed method, extraction and clean-up for hydrocarbons in soil can be achieved rapidly and efficiently with reduced solvent usage. (author)
Energy Technology Data Exchange (ETDEWEB)
Sharma, Ritin [ORNL; Dill, Brian [ORNL; Chourey, Karuna [ORNL; Shah, Manesh B [ORNL; Verberkmoes, Nathan C [ORNL; Hettich, Robert {Bob} L [ORNL
2012-01-01
The expanding use of surfactants for proteome sample preparations has prompted the need to systematically optimize the application and removal of these MS-deleterious agents prior to proteome measurements. Here we compare four different detergent clean-up methods (Trichloroacetic acid (TCA) precipitation, Chloroform/Methanol/Water (CMW) extraction, commercial detergent removal spin column method (DRS) and filter-aided sample preparation(FASP)) with respect to varying amounts of protein biomass in the samples, and provide efficiency benchmarks with respect to protein, peptide, and spectral identifications for each method. Our results show that for protein limited samples, FASP outperforms the other three clean-up methods, while at high protein amount all the methods are comparable. This information was used in a dual strategy of comparing molecular weight based fractionated and unfractionated lysates from three increasingly complex samples (Escherichia coli, a five microbial isolate mixture, and a natural microbial community groundwater sample), which were all lysed with SDS and cleaned up using FASP. The two approaches complemented each other by enhancing the number of protein identifications by 8%-25% across the three samples and provided broad pathway coverage.
Biocomplementation of SVE to achieve clean-up goals in soils contaminated with toluene and xylene.
Soares, António Alves; Pinho, Maria Teresa; Albergaria, José Tomás; Domingues, Valentina; da Conceição Alvim-Ferraz, Maria; Delerue-Matos, Cristina
2013-10-01
Soil vapor extraction (SVE) and bioremediation (BR) are two of the most common soil remediation technologies. Their application is widespread; however, both present limitations, namely related to the efficiencies of SVE on organic soils and to the remediation times of some BR processes. This work aimed to study the combination of these two technologies in order to verify the achievement of the legal clean-up goals in soil remediation projects involving seven different simulated soils separately contaminated with toluene and xylene. The remediations consisted of the application of SVE followed by biostimulation. The results show that the combination of these two technologies is effective and manages to achieve the clean-up goals imposed by the Spanish Legislation. Under the experimental conditions used in this work, SVE is sufficient for the remediation of soils, contaminated separately with toluene and xylene, with organic matter contents (OMC) below 4 %. In soils with higher OMC, the use of BR, as a complementary technology, and when the concentration of contaminant in the gas phase of the soil reaches values near 1 mg/L, allows the achievement of the clean-up goals. The OMC was a key parameter because it hindered SVE due to adsorption phenomena but enhanced the BR process because it acted as a microorganism and nutrient source.
Sectored Clean-up Work Plan for Housekeeping Category Waste Sites
International Nuclear Information System (INIS)
Nacht, S. J.
2000-01-01
The Sectored Clean-up Work Plan (SCWP) replaces the Housekeeping Category Corrective Action Unit Work Plan and provides a strategy to be used for conducting housekeeping activities using a sectored clean-up approach. This work plan provides a process by which one or more existing housekeeping category Corrective Action Sites (CASS) from the Federal Facility Agreement and Consent Order and/or non-FFACO designated waste site(s) are grouped into a sector for simultaneous remediation and cleanup. This increases effectiveness and efficiencies in labor, materials, equipment, cost, and time. This plan is an effort by the U.S. Department of Energy to expedite work in a more organized and efficient approach. The objectives of this plan are to: Group housekeeping FFACO CASS and non-FFACO housekeeping sites into sectors and remediate during the same field visit; Provide consistent documentation on FFACO CAS and non-FFACO clean-up activities; Perform similar activities under one approved document; Remediate areas inside the Deactivation and Decommissioning facilities and compounds in a campaign-style remediation; and Increase efficiencies and cost-effectiveness, accelerate cleanups, reduce mobilization, demobilization, and remediation costs
The effect of nonlinear forces on coherently oscillating space-charge-dominated beams
International Nuclear Information System (INIS)
Celata, C.M.
1987-03-01
A particle-in-cell computer simulation code has been used to study the transverse dynamics of nonrelativistic misaligned space-charge-dominated coasting beams in an alternating gradient focusing channel. In the presence of nonlinear forces due to dodecapole or octupole imperfections of the focusing fields or to image forces, the transverse rms emittance grows in a beat pattern. Analysis indicates that this emittance dilution is due to the driving of coherent modes of the beam near their resonant frequencies by the nonlinear force. The effects of the dodecapole and images forces can be made to effectively cancel for some boundary conditions, but the mechanism is not understood at this time
Nonlinear effects in the radiation force generated by amplitude-modulated focused beams
González, Nuria; Jiménez, Noé; Redondo, Javier; Roig, Bernardino; Picó, Rubén; Sánchez-Morcillo, Víctor; Konofagou, Elisa E.; Camarena, Francisco
2012-10-01
Harmonic Motion Imaging (HMI) uses an amplitude-modulated (AM) beam to induce an oscillatory radiation force before, during and after ablation. In this paper, the findings from a numerical analysis of the effects related with the nonlinear propagation of AM focused ultrasonic beams in water on the radiation force and the location of its maxima will be presented. The numerical modeling is performed using the KZK nonlinear parabolic equation. The radiation force is generated by a focused transducer with a gain of 18, a carrier frequency of 1 MHz and a modulation frequency of 25 kHz. The modulated excitation generates a spatially-invariant force proportional to the intensity. Regarding the nonlinear wave propagation, the force is no longer proportional to the intensity, reaching a factor of eight between the nonlinear and linear estimations. Also, a 9 mm shift in the on-axis force peak occurs when the initial pressure increased from 1 to 300 kPa. This spatial shift, due to the nonlinear effects, becomes dynamic in AM focused beams, as the different signal periods have different amplitudes. This study shows that both the value and the spatial position of the force peak are affected by the nonlinear propagation of the ultrasonic waves.
International Nuclear Information System (INIS)
Cho, Yeong-Kwon; Kim, Ki-Hong
2014-01-01
The propagation of optical vortex beams through disordered nonlinear photonic lattices is numerically studied. The vortex beams are generated by using a superposition of several Gaussian laser beams arranged in a radially-symmetric manner. The paraxial nonlinear Schroedinger equation describing the longitudinal propagation of the beam array through nonlinear triangular photonic lattices with two-dimensional disorder is solved numerically by using the split-step Fourier method. We find that due to the spatial disorder, the vortex beam is destabilized after propagating a finite distance and new vortex-antivortex pairs are nucleated at the positions of perfect destructive interference. We also find that in the presence of a self-focusing nonlinearity, the vortex-antivortex pair nucleation is suppressed and the vortex beam becomes more stable, while a self-defocusing nonlinearity enhances the vortex-antivortex pair nucleation.
Directory of Open Access Journals (Sweden)
Husain M. Husain
2013-05-01
Full Text Available In this work a program is developed to carry out the nonlinear analysis (material nonlinearity of prestressed concrete beams using tendons of carbon fiber reinforced polymer (CFRP instead of steel. The properties of this material include high strength, light weight, and insusceptibility to corrosion and magnetism. This material is still under investigation, therefore it needs continuous work to make it beneficial in concrete design. Four beams which are tested experimentally by Yan et al. are examined by the developed computer program to reach a certain analytical approach of the design and analysis of such beams because there is no available restrictions or recommendations covering this material in the codes. The program uses the finite element analysis by dividing the beams into isoparametric 20-noded brick elements. The results obtained are good in comparison with experimental results.
Relativistic and nonlinear radiation interaction between laser beams and plasmas
International Nuclear Information System (INIS)
Kane, E.L.; Hora, H.
1981-01-01
Starting from a combination of Maxwell's laws for the electromagnetic field and the conservation equations for a fully ionized plasma, the appropriate equations describing electrodynamic laser propagation and plasma dynamic particle motion are developed and solved. Calculations for multiply ionized transient conditions are carried out to yield electric field amplitudes, radial electron number density distributions and the progress of formation of a self-focused beam filament as a function of the target plasma density distribution and the laser pulse power-time history, among other parameters. Separate solutions emphasizing field-induced plasma motion on the one hand and significant beam contraction on the other are illustrated
Energy Technology Data Exchange (ETDEWEB)
Zou, Li [Dalian Univ. of Technology, Dalian City (China). State Key Lab. of Structural Analysis for Industrial Equipment; Liang, Songxin; Li, Yawei [Dalian Univ. of Technology, Dalian City (China). School of Mathematical Sciences; Jeffrey, David J. [Univ. of Western Ontario, London (Canada). Dept. of Applied Mathematics
2017-06-01
Nonlinear boundary value problems arise frequently in physical and mechanical sciences. An effective analytic approach with two parameters is first proposed for solving nonlinear boundary value problems. It is demonstrated that solutions given by the two-parameter method are more accurate than solutions given by the Adomian decomposition method (ADM). It is further demonstrated that solutions given by the ADM can also be recovered from the solutions given by the two-parameter method. The effectiveness of this method is demonstrated by solving some nonlinear boundary value problems modeling beam-type nano-electromechanical systems.
On the Possibility of Using Nonlinear Elements for Landau Damping in High-Intensity Beams
Energy Technology Data Exchange (ETDEWEB)
Alexahin, Y. [Fermilab; Gianfelice-Wendt, E. [Fermilab; Lebedev, V. [Fermilab; Valishev, A. [Fermilab
2016-09-30
Direct space-charge force shifts incoherent tunes downwards from the coherent ones breaking the Landau mechanism of coherent oscillations damping at high beam intensity. To restore it nonlinear elements can be employed which move back tunes of large amplitude particles. In the present report we consider the possibility of creating a “nonlinear integrable optics” insertion in the Fermilab Recycler to host either octupoles or hollow electron lens for this purpose. For comparison we also consider the classic scheme with distributed octupole families. It is shown that for the Proton Improvement Plan II (PIP II) parameters the required nonlinear tune shift can be created without destroying the dynamic aperture.
Cahill, Mark D.; Humphrey, Victor F.; Doody, Claire
2000-07-01
Thermal safety indices for diagnostic ultrasound beams are calculated under the assumption that the sound propagates under linear conditions. A non-axisymmetric finite difference model is used to solve the KZK equation, and so to model the beam of a diagnostic scanner in pulsed Doppler mode. Beams from both a uniform focused rectangular source and a linear array are considered. Calculations are performed in water, and in attenuating media with tissue-like characteristics. Attenuating media are found to exhibit significant nonlinear effects for finite-amplitude beams. The resulting loss of intensity by the beam is then used as the source term in a model of tissue heating to estimate the maximum temperature rises. These are compared with the thermal indices, derived from the properties of the water-propagated beams.
DEFF Research Database (Denmark)
Mamaev, A.V.; Saffman, M.; Zozulya, A.A.
1996-01-01
We analyze the evolution of (1+1) dimensional dark stripe beams in bulk media with a photorefractive nonlinear response. These beams, including solitary wave solutions, are shown to be unstable with respect to symmetry breaking and formation of structure along the initially homogeneous coordinate....... Experimental results show the complete sequence of events starting from self-focusing of the stripe, its bending due to the snake instability, and subsequent decay into a set of optical vortices....
Energy Technology Data Exchange (ETDEWEB)
Wu, Y. [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900 (China); Science and Technology on High Power Microwave Laboratory, Mianyang 621900 (China); Xu, Z.; Li, Z. H. [Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900 (China); Tang, C. X. [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)
2012-07-15
In intermediate cavities of a relativistic klystron amplifier (RKA) driven by intense relativistic electron beam, the equivalent circuit model, which is widely adopted to investigate the interaction between bunched beam and the intermediate cavity in a conventional klystron design, is invalid due to the high gap voltage and the nonlinear beam loading in a RKA. According to Maxwell equations and Lorentz equation, the self-consistent equations for beam-wave interaction in the intermediate cavity are introduced to study the nonlinear interaction between bunched beam and the intermediate cavity in a RKA. Based on the equations, the effects of modulation depth and modulation frequency of the beam on the gap voltage amplitude and its phase are obtained. It is shown that the gap voltage is significantly lower than that estimated by the equivalent circuit model when the beam modulation is high. And the bandwidth becomes wider as the beam modulation depth increases. An S-band high gain relativistic klystron amplifier is designed based on the result. And the corresponding experiment is carried out on the linear transformer driver accelerator. The peak output power has achieved 1.2 GW with an efficiency of 28.6% and a gain of 46 dB in the corresponding experiment.
Wu, Y.; Xu, Z.; Li, Z. H.; Tang, C. X.
2012-07-01
In intermediate cavities of a relativistic klystron amplifier (RKA) driven by intense relativistic electron beam, the equivalent circuit model, which is widely adopted to investigate the interaction between bunched beam and the intermediate cavity in a conventional klystron design, is invalid due to the high gap voltage and the nonlinear beam loading in a RKA. According to Maxwell equations and Lorentz equation, the self-consistent equations for beam-wave interaction in the intermediate cavity are introduced to study the nonlinear interaction between bunched beam and the intermediate cavity in a RKA. Based on the equations, the effects of modulation depth and modulation frequency of the beam on the gap voltage amplitude and its phase are obtained. It is shown that the gap voltage is significantly lower than that estimated by the equivalent circuit model when the beam modulation is high. And the bandwidth becomes wider as the beam modulation depth increases. An S-band high gain relativistic klystron amplifier is designed based on the result. And the corresponding experiment is carried out on the linear transformer driver accelerator. The peak output power has achieved 1.2 GW with an efficiency of 28.6% and a gain of 46 dB in the corresponding experiment.
Nonlinear hybrid simulation of internal kink with beam ion effects in DIII-D
Energy Technology Data Exchange (ETDEWEB)
Shen, Wei; Sheng, Zheng-Mao [Department of Physics, Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China); Fu, G. Y.; Tobias, Benjamin [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Zeeland, Michael Van [General Atomics, San Diego, California 92186-5608 (United States); Wang, Feng [School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China)
2015-04-15
In DIII-D sawteething plasmas, long-lived (1,1) kink modes are often observed between sawtooth crashes. The saturated kink modes have two distinct frequencies. The mode with higher frequency transits to a fishbone-like mode with sufficient on-axis neutral beam power. In this work, hybrid simulations with the global kinetic-magnetohydrodynamic (MHD) hybrid code M3D-K have been carried out to investigate the linear stability and nonlinear dynamics of the n = 1 mode with effects of energetic beam ions for a typical DIII-D discharge where both saturated kink mode and fishbone were observed. Linear simulation results show that the n = 1 internal kink mode is unstable in MHD limit. However, with kinetic effects of beam ions, a fishbone-like mode is excited with mode frequency about a few kHz depending on beam pressure profile. The mode frequency is higher at higher beam power and/or narrower radial profile consistent with the experimental observation. Nonlinear simulations have been performed to investigate mode saturation as well as energetic particle transport. The nonlinear MHD simulations show that the unstable kink mode becomes a saturated kink mode after a sawtooth crash. With beam ion effects, the fishbone-like mode can also transit to a saturated kink mode with a small but finite mode frequency. These results are consistent with the experimental observation of saturated kink mode between sawtooth crashes.
International Nuclear Information System (INIS)
Yildirim, Tanju; Ghayesh, Mergen H; Li, Weihua; Alici, Gursel
2016-01-01
An experimental investigation has been carried out on the nonlinear dynamics of a clamped–clamped Magneto-Rheological Elastomer (MRE) sandwich beam with a point mass when subjected to a point excitation. Three sets of experiments have been conducted namely for (i) an aluminium beam, (ii) a MRE sandwich beam in the absence of a magnetic field and (iii) a MRE sandwich beam in the presence of a magnetic field. An electrodynamic shaker was used to excite each system and the corresponding displacement of the point mass was measured: for the third experiment (iii), an array of magnets has been placed at various distances away from the centre of the point mass to investigate the effect of changing stiffness and damping properties on the nonlinear dynamical behaviour. An interesting feature for the third group is the beam point mass displacement was no longer symmetric as the stiffness and damping of the system are increased when moving towards the magnets. Both the first and second groups exhibited distinct nonlinear behaviour; however, for the third group this work shows that for a low magnetic field the sandwich beam exhibits two distinct resonance peaks, one occurring above and the other below the fundamental natural frequency of the transverse motion, with the right one larger. For a larger magnetic field, these peaks even out until the magnetic force was large enough that the hardening-type nonlinear behaviour changes to a softening-type; a significant qualitative change in the nonlinear dynamical behaviour of the system, due to the presence of the magnetic field, was observed. (paper)
Beam-Based Nonlinear Optics Corrections in Colliders
Pilat, Fulvia Caterina; Malitsky, Nikolay; Ptitsyn, Vadim
2005-01-01
A method has been developed to measure and correct operationally the non-linear effects of the final focusing magnets in colliders, which gives access to the effects of multi-pole errors by applying closed orbit bumps, and analyzing the resulting tune and orbit shifts. This technique has been tested and used during 3 years of RHIC (the Relativistic Heavy Ion Collider at BNL) operations. I will discuss here the theoretical basis of the method, the experimental set-up, the correction results, the present understanding of the machine model, the potential and limitations of the method itself as compared with other non linear correction techniques.
Invariant measures for stochastic nonlinear beam and wave equations
Czech Academy of Sciences Publication Activity Database
Brzezniak, Z.; Ondreját, Martin; Seidler, Jan
2016-01-01
Roč. 260, č. 5 (2016), s. 4157-4179 ISSN 0022-0396 R&D Projects: GA ČR GAP201/10/0752 Institutional support: RVO:67985556 Keywords : stochastic partial differential equation * stochastic beam equation * stochastic wave equation * invariant measure Subject RIV: BA - General Mathematics Impact factor: 1.988, year: 2016 http://library.utia.cas.cz/separaty/2016/SI/ondrejat-0453412.pdf
Numerical methods for axisymmetric and 3D nonlinear beams
Pinton, Gianmarco F.; Trahey, Gregg E.
2005-04-01
Time domain algorithms that solve the Khokhlov--Zabolotzskaya--Kuznetsov (KZK) equation are described and implemented. This equation represents the propagation of finite amplitude sound beams in a homogenous thermoviscous fluid for axisymmetric and fully three dimensional geometries. In the numerical solution each of the terms is considered separately and the numerical methods are compared with known solutions. First and second order operator splitting are used to combine the separate terms in the KZK equation and their convergence is examined.
Nonlinear Delta-f Particle Simulations of Collective Effects in High-Intensity Bunched Beams
Qin, Hong; Hudson, Stuart R; Startsev, Edward
2005-01-01
The collective effects in high-intensity 3D bunched beams are described self-consistently by the nonlinear Vlasov-Maxwell equations.* The nonlinear delta-f method,** a particle simulation method for solving the nonlinear Vlasov-Maxwell equations, is being used to study the collective effects in high-intensity 3D bunched beams. The delta-f method, as a nonlinear perturbative scheme, splits the distribution function into equilibrium and perturbed parts. The perturbed distribution function is represented as a weighted summation over discrete particles, where the particle orbits are advanced by equations of motion in the focusing field and self-consistent fields, and the particle weights are advanced by the coupling between the perturbed fields and the zero-order distribution function. The nonlinear delta-f method exhibits minimal noise and accuracy problems in comparison with standard particle-in-cell simulations. A self-consistent 3D kinetic equilibrium is first established for high intensity bunched beams. The...
Energy Technology Data Exchange (ETDEWEB)
Spata, Michael [Old Dominion Univ., Norfolk, VA (United States)
2012-08-01
An experiment was conducted at Jefferson Lab's Continuous Electron Beam Accelerator Facility to develop a beam-based technique for characterizing the extent of the nonlinearity of the magnetic fields of a beam transport system. Horizontally and vertically oriented pairs of air-core kicker magnets were simultaneously driven at two different frequencies to provide a time-dependent transverse modulation of the beam orbit relative to the unperturbed reference orbit. Fourier decomposition of the position data at eight different points along the beamline was then used to measure the amplitude of these frequencies. For a purely linear transport system one expects to find solely the frequencies that were applied to the kickers with amplitudes that depend on the phase advance of the lattice. In the presence of nonlinear fields one expects to also find harmonics of the driving frequencies that depend on the order of the nonlinearity. Chebyshev polynomials and their unique properties allow one to directly quantify the magnitude of the nonlinearity with the minimum error. A calibration standard was developed using one of the sextupole magnets in a CEBAF beamline. The technique was then applied to a pair of Arc 1 dipoles and then to the magnets in the Transport Recombiner beamline to measure their multipole content as a function of transverse position within the magnets.
Oscillations of a Beam on a Non-Linear Elastic Foundation under Periodic Loads
Directory of Open Access Journals (Sweden)
Donald Mark Santee
2006-01-01
Full Text Available The complexity of the response of a beam resting on a nonlinear elastic foundation makes the design of this structural element rather challenging. Particularly because, apparently, there is no algebraic relation for its load bearing capacity as a function of the problem parameters. Such an algebraic relation would be desirable for design purposes. Our aim is to obtain this relation explicitly. Initially, a mathematical model of a flexible beam resting on a non-linear elastic foundation is presented, and its non-linear vibrations and instabilities are investigated using several numerical methods. At a second stage, a parametric study is carried out, using analytical and semi-analytical perturbation methods. So, the influence of the various physical and geometrical parameters of the mathematical model on the non-linear response of the beam is evaluated, in particular, the relation between the natural frequency and the vibration amplitude and the first period doubling and saddle-node bifurcations. These two instability phenomena are the two basic mechanisms associated with the loss of stability of the beam. Finally Melnikov's method is used to determine an algebraic expression for the boundary that separates a safe from an unsafe region in the force parameters space. It is shown that this can be used as a basis for a reliable engineering design criterion.
Nonlinear Charge and Current Neutralization of an Ion Beam Pulse in a Pre-formed Plasma
International Nuclear Information System (INIS)
Kaganovich, Igor D.; Shvets, Gennady; Startsev, Edward; Davidson, Ronald C.
2001-01-01
The propagation of a high-current finite-length ion beam in a cold pre-formed plasma is investigated. The outcome of the calculation is the quantitative prediction of the degree of charge and current neutralization of the ion beam pulse by the background plasma. The electric magnetic fields generated by the ion beam are studied analytically for the nonlinear case where the plasma density is comparable in size with the beam density. Particle-in-cell simulations and fluid calculations of current and charge neutralization have been performed for parameters relevant to heavy ion fusion assuming long, dense beams with el >> V(subscript b)/omega(subscript b), where V(subscript b) is the beam velocity and omega subscript b is the electron plasma frequency evaluated with the ion beam density. An important conclusion is that for long, nonrelativistic ion beams, charge neutralization is, for all practical purposes, complete even for very tenuous background plasmas. As a result, the self-magnetic force dominates the electric force and the beam ions are always pinched during beam propagation in a background plasma
Nonlinear Charge and Current Neutralization of an Ion Beam Pulse in a Pre-formed Plasma
Energy Technology Data Exchange (ETDEWEB)
Igor D. Kaganovich; Gennady Shvets; Edward Startsev; Ronald C. Davidson
2001-01-30
The propagation of a high-current finite-length ion beam in a cold pre-formed plasma is investigated. The outcome of the calculation is the quantitative prediction of the degree of charge and current neutralization of the ion beam pulse by the background plasma. The electric magnetic fields generated by the ion beam are studied analytically for the nonlinear case where the plasma density is comparable in size with the beam density. Particle-in-cell simulations and fluid calculations of current and charge neutralization have been performed for parameters relevant to heavy ion fusion assuming long, dense beams with el >> V(subscript b)/omega(subscript b), where V(subscript b) is the beam velocity and omega subscript b is the electron plasma frequency evaluated with the ion beam density. An important conclusion is that for long, nonrelativistic ion beams, charge neutralization is, for all practical purposes, complete even for very tenuous background plasmas. As a result, the self-magnetic force dominates the electric force and the beam ions are always pinched during beam propagation in a background plasma.
Non-Linear Beam Transport System for the LENS 7 MeV Proton Beam
Jones, William P; Derenchuk, Vladimir Peter; Rinckel, Thomas; Solberg, Keith
2005-01-01
A beam transport system has been designed to carry a high-intensity low-emittance proton beam from the exit of the RFQ-DTL acceleration system of the Indiana University Low Energy Neutron System (LENS)* to the neutron production target. The goal of the design was to provide a beam of uniform density over a 3cm by 3cm area at the target. Two octupole magnets** are employed in the beam line to provide the necessary beam phase space manipulations to achieve this goal. First order calculations were done using TRANSPORT and second order calculations have been performed using TURTLE. Second order simulations have been done using both a Gaussian beam distribution and a particle set generated by calculations of beam transport through the RFQ-DTL using PARMILA. Comparison of the design characteristics with initial measurements from the LENS commissioning process will be made.
Next steps in the development of ecological soil clean-up values for metals.
Wentsel, Randall; Fairbrother, Anne
2014-07-01
This special series in Integrated Environmental Assessment Management presents the results from 6 workgroups that were formed at the workshop on Ecological Soil Levels-Next Steps in the Development of Metal Clean-Up Values (17-21 September 2012, Sundance, Utah). This introductory article presents an overview of the issues assessors face when conducting risk assessments for metals in soils, key US Environmental Protection Agency (USEPA) documents on metals risk assessment, and discusses the importance of leveraging from recent major terrestrial research projects, primarily to address Registration, Evaluation, Authorization and Restriction of Chemical Substances (REACH) requirements in Europe, that have significantly advanced our understanding of the behavior and toxicity of metals in soils. These projects developed large data sets that are useful for the risk assessment of metals in soil environments. The workshop attendees met to work toward developing a process for establishing ecological soil clean-up values (Eco-SCVs). The goal of the workshop was to progress from ecological soil screening values (Eco-SSLs) to final clean-up values by providing regulators with the methods and processes to incorporate bioavailability, normalize toxicity thresholds, address food-web issues, and incorporate background concentrations. The REACH data sets were used by workshop participants as case studies in the development of the ecological standards for soils. The workshop attendees discussed scientific advancements in bioavailability, soil biota and wildlife case studies, soil processes, and food-chain modeling. In addition, one of the workgroups discussed the processes needed to frame the topics to gain regulatory acceptance as a directive or guidance by Canada, the USEPA, or the United States. © 2013 SETAC.
Demand driven salt clean-up in a molten salt fast reactor - Defining a priority list.
Merk, B; Litskevich, D; Gregg, R; Mount, A R
2018-01-01
The PUREX technology based on aqueous processes is currently the leading reprocessing technology in nuclear energy systems. It seems to be the most developed and established process for light water reactor fuel and the use of solid fuel. However, demand driven development of the nuclear system opens the way to liquid fuelled reactors, and disruptive technology development through the application of an integrated fuel cycle with a direct link to reactor operation. The possibilities of this new concept for innovative reprocessing technology development are analysed, the boundary conditions are discussed, and the economic as well as the neutron physical optimization parameters of the process are elucidated. Reactor physical knowledge of the influence of different elements on the neutron economy of the reactor is required. Using an innovative study approach, an element priority list for the salt clean-up is developed, which indicates that separation of Neodymium and Caesium is desirable, as they contribute almost 50% to the loss of criticality. Separating Zirconium and Samarium in addition from the fuel salt would remove nearly 80% of the loss of criticality due to fission products. The theoretical study is followed by a qualitative discussion of the different, demand driven optimization strategies which could satisfy the conflicting interests of sustainable reactor operation, efficient chemical processing for the salt clean-up, and the related economic as well as chemical engineering consequences. A new, innovative approach of balancing the throughput through salt processing based on a low number of separation process steps is developed. Next steps for the development of an economically viable salt clean-up process are identified.
Attractor of Beam Equation with Structural Damping under Nonlinear Boundary Conditions
Directory of Open Access Journals (Sweden)
Danxia Wang
2015-01-01
Full Text Available Simultaneously, considering the viscous effect of material, damping of medium, and rotational inertia, we study a kind of more general Kirchhoff-type extensible beam equation utt-uxxtt+uxxxx-σ(∫0l(ux2dxuxx-ϕ(∫0l(ux2dxuxxt=q(x, in [0,L]×R+ with the structural damping and the rotational inertia term. Little attention is paid to the longtime behavior of the beam equation under nonlinear boundary conditions. In this paper, under nonlinear boundary conditions, we prove not only the existence and uniqueness of global solutions by prior estimates combined with some inequality skills, but also the existence of a global attractor by the existence of an absorbing set and asymptotic compactness of corresponding solution semigroup. In addition, the same results also can be proved under the other nonlinear boundary conditions.
Directory of Open Access Journals (Sweden)
C. E. M. Oliveira
Full Text Available This work investigates the response of two reinforced concrete (RC plane frames after the loss of a column and their potential resistance for progressive collapse. Nonlinear dynamic analysis is performed using a multilayered Euler/Bernoulli beam element, including elasto-viscoplastic effects. The material nonlinearity is represented using one-dimensional constitutive laws in the material layers, while geometrical nonlinearities are incorporated within a corotational beam formulation. The frames were designed in accordance with the minimum requirements proposed by the reinforced concrete design/building codes of Europe (fib [1-2], Eurocode 2 [3] and Brazil (NBR 6118 [4]. The load combinations considered for PC analysis follow the prescriptions of DoD [5]. The work verifies if the minimum requirements of the considered codes are sufficient for enforcing structural safety and robustness, and also points out the major differences in terms of progressive collapse potential of the corresponding designed structures.
Mimicking the cochlear amplifier in a cantilever beam using nonlinear velocity feedback control
International Nuclear Information System (INIS)
Joyce, Bryan S; Tarazaga, Pablo A
2014-01-01
The mammalian cochlea exhibits a nonlinear amplification which allows mammals to detect a large range of sound pressure levels while maintaining high frequency sensitivity. This work seeks to mimic the cochlea’s nonlinear amplification in a mechanical system. A nonlinear, velocity-based feedback control law is applied to a cantilever beam with piezoelectric actuators. The control law reduces the linear viscous damping of the system while introducing a cubic damping term. The result is a system which is positioned close to a Hopf bifurcation. Modelling and experimental results show that the beam with this control law undergoes a one-third amplitude scaling near the resonance frequency and an amplitude-dependent bandwidth. Both behaviors are characteristic of data obtained from the mammalian cochlea. This work could provide insight on the biological cochlea while producing bio-inspired sensors with a large dynamic range and sharp frequency sensitivity. (papers)
Mimicking the cochlear amplifier in a cantilever beam using nonlinear velocity feedback control
Joyce, Bryan S.; Tarazaga, Pablo A.
2014-07-01
The mammalian cochlea exhibits a nonlinear amplification which allows mammals to detect a large range of sound pressure levels while maintaining high frequency sensitivity. This work seeks to mimic the cochlea’s nonlinear amplification in a mechanical system. A nonlinear, velocity-based feedback control law is applied to a cantilever beam with piezoelectric actuators. The control law reduces the linear viscous damping of the system while introducing a cubic damping term. The result is a system which is positioned close to a Hopf bifurcation. Modelling and experimental results show that the beam with this control law undergoes a one-third amplitude scaling near the resonance frequency and an amplitude-dependent bandwidth. Both behaviors are characteristic of data obtained from the mammalian cochlea. This work could provide insight on the biological cochlea while producing bio-inspired sensors with a large dynamic range and sharp frequency sensitivity.
Husakou, A; Herrmann, J
2006-11-13
We evaluate the possibility to focus scanning light beams below the diffraction limit by using the combination of a nonlinear material with a Kerr-type nonlinearity or two-photon absorption to create seed evanescent components of the beam and a negative-refraction material to enhance them. Superfocusing to spots with a FWHM in the range of 0.2 lambda is theoretically predicted both in the context of the effective-medium theory and by the direct numerical solution of Maxwell equations for an inhomogeneous pho-tonic crystal. The evolution of the transverse spectrum and the dependence of superfocusing on the parameters of the negative-refraction material are also studied. We show that the use of a Kerr-type nonlinear layer for the creation of seed evanescent components yields focused spots with a higher intensity compared with those obtained by the application of a saturable absorber.
LC clean-up and GC/MS analysis of polycyclic aromatic hydrocarbons in river sediment
International Nuclear Information System (INIS)
Nondek, L.; Kuzilek, M.; Krupicka, S.
1993-01-01
An LC clean-up procedure based upon a complexation between polycyclic aromatic hydrocarbons (PAHs) and silica with chemically bonded 2,4-dinitroaniline has been combined with GC/MS. The LC pre-separation makes it possible to obtain a relatively clean fraction of PAHs free from alkanes, alkylbenzenes and naphthalenes, PCBs, chlorinated pesticides and many other interfering compounds. This fraction has been analyzed using capillary GC and mass selective detector (MSD). Substantial improvement of the MS spectra of PAHs with three or more fused benzene rings is achieved. (orig.)
Key Lake mine water spill: further clean-up not required
International Nuclear Information System (INIS)
Potvin, R.
1984-02-01
The Atomic Energy Control Board (AECB) has concluded that no additional remedial measures are warranted with regard to the mine water spill which occurred in early January at the Key Lake Mining Corporation facility in northern Saskatchewan, and has advised the company to reconsider its proposal for clean-up of the adjoining Gerald Lake basin. On January 5, an estimated 87 million litres of mine water was accidentally released to the environment when a water storage reservoir at the mine site overflowed. The spilled water flowed into the adjoining Gerald Lake catchment area where it has remained adequately contained
Early phase clean-up actions after nuclear accidents. Guidelines for the planner. Final report
International Nuclear Information System (INIS)
Ulvsand, T.
1997-06-01
The work reported has been performed with the purpose of working out a guide for planners of early clean-up actions in nuclear fallout situations and for decision makers in the Nordic countries. The actions considered are hosing of roofs, walls and paved areas, lawn mowing, removal of snow, pruning of trees and bushes and vacuum cleaning of streets. The expected effects, mainly as life time dose reduction, and consequences regarding practicability, waste produced, staffing and protection are presented for urban, suburban and rural living environments. The work has been performed within the fram work of the Nordic Nuclear Safety Research Program 1994-97 (Statens Raeddningsverk). (au)
Mechanical nonlinearity elimination with a micromechanical clamped-free semicircular beams resonator
Chen, Dongyang; Chen, Xuying; Wang, Yong; Liu, Xinxin; Guan, Yangyang; Xie, Jin
2018-04-01
This paper reports a micro-machined clamped-free semicircular beam resonator aiming to eliminate the nonlinearity that widely exists in traditional mechanical resonators. Cubic coefficients over vibration displacement due to axial extension of the beams are analyzed through theoretical modelling, and the corresponding frequency effect is demonstrated. With the device working in the elastic vibration mode, the cubic coefficients are eliminated by using a free end to release the nonlinear extension of beams and thus the inside axial stress. The amplitude-frequency (A-f) effect is overcome in a large region of source power, and the coefficient of frequency softening is linearized in a large region of polarization voltage. As a result, the resonator can be driven at larger vibration amplitude to achieve a high signal to noise ratio and power handling performance.
Directory of Open Access Journals (Sweden)
H. Vázquez-Leal
2013-01-01
Full Text Available In theoretical mechanics field, solution methods for nonlinear differential equations are very important because many problems are modelled using such equations. In particular, large deflection of a cantilever beam under a terminal follower force and nonlinear pendulum problem can be described by the same nonlinear differential equation. Therefore, in this work, we propose some approximate solutions for both problems using nonlinearities distribution homotopy perturbation method, homotopy perturbation method, and combinations with Laplace-Padé posttreatment. We will show the high accuracy of the proposed cantilever solutions, which are in good agreement with other reported solutions. Finally, for the pendulum case, the proposed approximation was useful to predict, accurately, the period for an angle up to 179.99999999∘ yielding a relative error of 0.01222747.
In-plane and out-of-plane nonlinear dynamics of an axially moving beam
International Nuclear Information System (INIS)
Farokhi, Hamed; Ghayesh, Mergen H.; Amabili, Marco
2013-01-01
In the present study, the nonlinear forced dynamics of an axially moving beam is investigated numerically taking into account the in-plane and out-of-plane motions. The nonlinear partial differential equations governing the motion of the system are derived via Hamilton’s principle. The Galerkin scheme is then introduced to these partial differential equations yielding a set of second-order nonlinear ordinary differential equations with coupled terms. This set is transformed into a new set of first-order nonlinear ordinary differential equations by means of a change of variables. A direct time integration technique is conducted upon the new set of equations resulting in the bifurcation diagrams of Poincaré maps of the system. The dynamical characteristics of the system are investigated for different system parameters and presented through use of time histories, phase-plane portraits, Poincaré sections, and fast Fourier transforms
Nonlinear Analysis of External Prestressed Reinforced Concrete Beams with BFRP and CFRP
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Haleem K. Hussain
2017-05-01
Full Text Available The traditional strengthening methods for concrete structure (girders, beams, columns…. consuming time and could be an economical, a new modern repair methods using the Carbon Fiber Reinforced Polymers (CFRP and Basalt Fiber Reinforced Polymer (BFRP as a laminate strips or bars,and considered a competitive solution that will increase the life-cycle of repaired structures. This study investigated the strengthen reinforced concrete girder. Nonlinear analysis have been adopted to the models using FEM analysis (ANSYS to simulate the theoretical results compared with experimental results.Using finite element packages, more efficient and better analyses can be made to fully understand the response of individual structural components and their contribution to a structure as a whole.Three type of material are used in this study as an external prestressed wire (steel, CFRP and BFRP. The prestressed beam is modeled as simply supported beam with two concentrated point load. The results showed that all tested strengthening beam increased the load carryingcapacity of the beams depend on prestressing force. Obtained Result was compared for different type of beam.This study also was enlarged to include using CFRP and BFRPbarwhich are light weight and moredurable, lead to ease of handling and maintenance. The research conducted analytical work to evaluate the effectiveness of concrete beams reinforced normally by the use of CFRP and BFRP bars. The results showed a significant gain in the beam’s ultimate capacities using CFRP bars comparing with beam reinforced with BFRP bar and reference beam
Site-specific sediment clean-up objectives developed by the sediment quality triad
International Nuclear Information System (INIS)
Redman, S.; Janisch, T.
1995-01-01
Sediment chemistry, sediment toxicity, and benthic macroinvertebrate community data were collected and evaluated in concert (1) to characterize adverse effects of hydrocarbon and metal contaminants in the sediments of a small inlet of Superior Bay, Lake Superior and a tributary creek and (2) to derive numeric objectives for the clean up of this system. Sediments from reference locations and eight study sites were analyzed for a range of contaminants, including hydrocarbons (measured both as diesel range organics (DRO) and oil and grease), lead, chromium, and ammonia. A range of sediment toxicity was observed across the eight study sites using a variety of tests and endpoints: Hyalella azteca (10 day survival and growth), Chironomus tentans (10 day survival and growth), Ceriodaphnia dubia (48 hour survival), and Daphnia magna (48 hour survival and 10 day survival and reproduction). A range of alterations of the benthic macroinvertebrate community compared with communities from reference locations were observed. Benthic community alterations were summarized quantitatively by taxa richness and Shannon-Weiner mean diversity. Lowest effect levels determined through this study included 150 microg/g dry sediment for DRO (as measured in this study) and 40 microg/g dry sediment for lead. Effects thresholds determined through this study included 1,500 microg/g dry sediment for DRO and 90 microg/g dry sediment for lead. These levels and concentrations measured in relevant reference locations are being used to define objectives for sediment clean up in the inlet and creek
Opukushi horizontal well campaign: completion design and wellbore clean-up
Energy Technology Data Exchange (ETDEWEB)
Osode, P. I.; Dijkema, R. W. [Shell Petroleum Development Company of Nigeria (Nigeria)
1998-12-31
A three-well completion design and installation technique, and a horizontal well clean-up procedure employed as part of the on-going initiative to improve the Opukushi Oilfield in Nigeria was described. In an effort to improve the Field`s ultimate recovery and production potential, horizontal well technology was introduced during the second phase of field development which started in 1995. Openhole liner completion was the design of choice, dictated by the unconsolidated sandstone formation which characterizes the shallow horizons of the field. All three wells were completed in thin oil rim sands of about 70 ft, with 5-1/2 inch by 4-1/2 inch tapered slotted liner assemblies installed across 2300 to 3300 ft of 8-1/2 inch drainhole sections. Drilling was completed with low-solids drilling fluid; well clean-up was done with a coil-tubing unit using nitrified acid at underbalance condition. In addition to a description of the design and liner completion considerations, the paper also includes a comparison of performance data from the three wells with performance of conventional wells. A productivity improvement factor of 10 or better was reported for each of the wells. 6 refs., 2 tabs., 14 figs.
International Nuclear Information System (INIS)
Jung, Sung Hee; Kim Jong Bum; Choi, Byung Jong
2004-03-01
Radiotracer experiments were carried out on a cylindrical 2-stage anaerobic sludge digester in order to investigate the improvement of its efficiency by means of RTD (Residence Time Distribution) measurements before and after cleaning up the inside of the digester. The tracer was Sc-46 in an EDTA solution which forms such a stable complex compound to keep the isotope from being absorbed onto the surface of the pipelines or the wall. It was injected into the digester by pressurized nitrogen gas and its movement was monitored by NaI(Tl) scintillation detectors installed around the digester and recorded for a month by a 24-channel data acquisition system specially developed for radiotracer experiments by the Korea Tracer Group of KAERI. The experimental data was analyzed for the MRT (Mean Residence Time) and other parameters characterizing the flow behavior. After the cleaning of the digesters the variance has been decreased and the sludge dynamics was activated as a result of the increase of the effective volume from 20% to 80% after cleaning up in the secondary digester. Particularly the MRT of the secondary digester which has no mixing mechanism has been increased by 3 times
Evaluation of concepts for a NET plasma exhaust clean-up system
International Nuclear Information System (INIS)
Glugla, M.; Penzhorn, R.D.; Rodriguez, R.; Herbrechter, D.; Dinner, P.; Murdoch, D.
1990-07-01
The process steps for the off-gas clean-up and direct recovery of the unburned fuel gases deuterium and tritium are, together with the isotope separation and the fuel preparation, the major subsystems within the fuel cycle of a fusion reactor. A comparison between process concepts largely based on experimental work at KfK and other process alternatives discussed in the literature is carried out and the various options are evaluated on the basis of the process requirements for NET I. The recovery of most of the unburned hydrogen with a palladium/silver permeator is selected as a first step, common to all seven concepts. The remaining impurity stream is processed either catalytically, with the help of getters, or by oxidation followed by reduction of the produced water. The physicochemical basis of each process alternative is discussed and the corresponding chemical flow sheets (flow diagrams and material flow tables) are presented. Concepts employing getters are unattractive because the produce untolerably high amounts of solid waste. Main drawbacks of process options involving an oxidation step are the non-discriminative oxidation of hydrogen and impurities as well as the non-trivial reduction of the produced highly tritiated water at the required elevated throughput. Advantages of the catalytic process are the production of little solid waste, the low steady state inventory and the comparatively easy scale-up. The catalytic process is therefore considered the most promising option for the development of a fuel clean-up process. (orig./HK) [de
Early aging in Chernobyl clean-up workers: long-term study.
Krasnov, V; Kryukov, V; Samedova, E; Emelianova, I; Ryzhova, I
2015-01-01
This paper represents data of long-term open prospective study. 312 male clean-up workers, who participated in elimination of the Chernobyl disaster consequences in 1986-87, were observed and examined in Moscow Research Institute of Psychiatry. The average age of patients was 57,0 ± 6,8 years. All patients were diagnosed with psychoorganic syndrome, caused by combination of different factors, which led to early cerebrovascular pathology, which was confirmed by clinical, neuropsychological, and instrumental examination. Anamnesis and the level of social adaptation were also assayed. Clinical estimation was done with the use of specially developed Clinical Psychopathological Chart. All the symptoms were divided into 4 groups (asthenic, psychovegetative, dysthymic, and cognitive symptom-complexes). No pronounced signs of dementia were observed. The control group included 44 clean-up workers without mental disorders. Predomination of various exogenous factors before and after accident was noted. Therapy included different vasotropic remedies, as well as family therapy, art therapy, and cognitive training. The possibilities of the reverse development of symptoms were statistically proved. The results allow making a conclusion that these disorders could not be explained either by radiation effects or by PTSD but connected with cerebrovascular pathology.
Early Aging in Chernobyl Clean-Up Workers: Long-Term Study
Directory of Open Access Journals (Sweden)
V. Krasnov
2015-01-01
Full Text Available This paper represents data of long-term open prospective study. 312 male clean-up workers, who participated in elimination of the Chernobyl disaster consequences in 1986-87, were observed and examined in Moscow Research Institute of Psychiatry. The average age of patients was 57,0 ± 6,8 years. All patients were diagnosed with psychoorganic syndrome, caused by combination of different factors, which led to early cerebrovascular pathology, which was confirmed by clinical, neuropsychological, and instrumental examination. Anamnesis and the level of social adaptation were also assayed. Clinical estimation was done with the use of specially developed Clinical Psychopathological Chart. All the symptoms were divided into 4 groups (asthenic, psychovegetative, dysthymic, and cognitive symptom-complexes. No pronounced signs of dementia were observed. The control group included 44 clean-up workers without mental disorders. Predomination of various exogenous factors before and after accident was noted. Therapy included different vasotropic remedies, as well as family therapy, art therapy, and cognitive training. The possibilities of the reverse development of symptoms were statistically proved. The results allow making a conclusion that these disorders could not be explained either by radiation effects or by PTSD but connected with cerebrovascular pathology.
Khomaziuk, I M; Habulavichene, Zh M; Khomaziuk, V A
2011-01-01
Particularities and clinical importance of the structural and functional changes of myocardium were estimated in Chernobyl disaster clean-up workers with atrial fibrillation (AF). We examined 122 men with AF, which was associated with ischemic heart disease and arterial hypertension. Paroxysmal AF was diagnosed in 42 patients, 80 patients had permanent AE Control group comprised 80 men without AF. Echocardiography and Doppler studies were performed using ultrasound scanner Aloka SSD-630 (Japan). Significant structural and functional changes of the heart were revealed already in paroxysmal AF and became more pronounced in permanent AF. Increased left atrial size, its ratio to left ventricular end diastolic diameter, diastolic dysfunction were important echocardiographic predictors of AF. Heart walls thickening was accompanied by disorders of myocardial relaxation, increase in myocardial mass led to ischemia, and together they promoted overload, dysfunction of atrium and development of AF. Obligatory echocardiographic examination of the Chernobyl disaster clean-up workers with ischemic heart disease and arterial hypertension is necessary for predicting AF early, ordering adequate therapy in proper time and improving prognosis.
Dosimetric monitoring at time of Chernobyl clean-up. A retrospective view
International Nuclear Information System (INIS)
Chumak, V.V.; Bakhanova, E.V.; Musijachenko, N.V.; Krjuchkov, V.P.
2000-01-01
Although at time of the accident many thousands of individuals were subjected to personal dosimetric monitoring, a status of dosimetric support of clean-up activities performed in 1986-1987 remains one of the most uncertain radiological issues related to Chernobyl accident. It is known that the scope, practical coverage and methodologies of dosimetry at time of the accident significantly varied. Unfortunately, the dose records available now in a number registries and databases are lacking direct indications of the methods of dosimetry, locations of work and tasks performed by liquidators. Moreover, data record linkage in many cases is problematic due to lack of unique identifiers in the databases of concern. However, this information, collected in course of dosimetric monitoring is extremely valuable for epidemiological consideration of this cohort and, therefore, cannot be neglected because of problems with strait forward application of this data. Retrospective consideration of dosimetric monitoring data was conducted along several lines. First, data sets (in some cases impersonal), related to the known dosimetric practices were studied in order to determine regularities in their dose distributions, evaluate possible distortions caused by extraneous admixtures to dose arrays and evaluate possible contribution of falsified dose records. Another effort was directed towards individualization of information regarding affiliation and tasks of the liquidators included into the State Chernobyl Registry (SCR), which is, essentially, the main pool of subjects for observation in the framework of post Chernobyl epidemiological studies. The SCR in its original shape was missing this crucial information. In order to recover this information gap, a wide scale postal survey of liquidators was undertaken. Those persons who are included into the State Chernobyl Registry and have official dose records were asked to respond to a simple five-entry questionnaire, dealing with their
A self-consistent nonlinear theory of resistive-wall instability in a relativistic electron beam
International Nuclear Information System (INIS)
Uhm, H.S.
1994-01-01
A self-consistent nonlinear theory of resistive-wall instability is developed for a relativistic electron beam propagating through a grounded cylindrical resistive tube. The theory is based on the assumption that the frequency of the resistive-wall instability is lower than the cutoff frequency of the waveguide. The theory is concentrated on study of the beam current modulation directly related to the resistive-wall klystron, in which a relativistic electron beam is modulated at the first cavity and propagates downstream through the resistive wall. Because of the self-excitation of the space charge waves by the resistive-wall instability, a highly nonlinear current modulation of the electron beam is accomplished as the beam propagates downstream. A partial integrodifferential equation is obtained in terms of the initial energy modulation (ε), the self-field effects (h), and the resistive-wall effects (κ). Analytically investigating the partial integrodifferential equation, a scaling law of the propagation distance z m at which the maximum current modulation occurs is obtained. It is found in general that the self-field effects dominate over the resistive-wall effects at the beginning of the propagation. As the beam propagates farther downstream, the resistive-wall effects dominate. Because of a relatively large growth rate of the instability, the required tube length of the klystron is short for most applications
Giant nonlinear interaction between two optical beams via a quantum dot embedded in a photonic wire
Nguyen, H. A.; Grange, T.; Reznychenko, B.; Yeo, I.; de Assis, P.-L.; Tumanov, D.; Fratini, F.; Malik, N. S.; Dupuy, E.; Gregersen, N.; Auffèves, A.; Gérard, J.-M.; Claudon, J.; Poizat, J.-Ph.
2018-05-01
Optical nonlinearities usually appear for large intensities, but discrete transitions allow for giant nonlinearities operating at the single-photon level. This has been demonstrated in the last decade for a single optical mode with cold atomic gases, or single two-level systems coupled to light via a tailored photonic environment. Here, we demonstrate a two-mode giant nonlinearity with a single semiconductor quantum dot (QD) embedded in a photonic wire antenna. We exploit two detuned optical transitions associated with the exciton-biexciton QD level scheme. Owing to the broadband waveguide antenna, the two transitions are efficiently interfaced with two free-space laser beams. The reflection of one laser beam is then controlled by the other beam, with a threshold power as low as 10 photons per exciton lifetime (1.6 nW ). Such a two-color nonlinearity opens appealing perspectives for the realization of ultralow-power logical gates and optical quantum gates, and could also be implemented in an integrated photonic circuit based on planar waveguides.
Directory of Open Access Journals (Sweden)
Virginijus Barzda
2013-09-01
Full Text Available Differential polarization nonlinear optical microscopy has the potential to become an indispensable tool for structural investigations of ordered biological assemblies and microcrystalline aggregates. Their microscopic organization can be probed through fast and sensitive measurements of nonlinear optical signal anisotropy, which can be achieved with microscopic spatial resolution by using time-multiplexed pulsed laser beams with perpendicular polarization orientations and photon-counting detection electronics for signal demultiplexing. In addition, deformable membrane mirrors can be used to correct for optical aberrations in the microscope and simultaneously optimize beam overlap using a genetic algorithm. The beam overlap can be achieved with better accuracy than diffraction limited point-spread function, which allows to perform polarization-resolved measurements on the pixel-by-pixel basis. We describe a newly developed differential polarization microscope and present applications of the differential microscopy technique for structural studies of collagen and cellulose. Both, second harmonic generation, and fluorescence-detected nonlinear absorption anisotropy are used in these investigations. It is shown that the orientation and structural properties of the fibers in biological tissue can be deduced and that the orientation of fluorescent molecules (Congo Red, which label the fibers, can be determined. Differential polarization microscopy sidesteps common issues such as photobleaching and sample movement. Due to tens of megahertz alternating polarization of excitation pulses fast data acquisition can be conveniently applied to measure changes in the nonlinear signal anisotropy in dynamically changing in vivo structures.
Finite Element Model for Nonlinear Analysis of Reinforced Concrete Beams and Plane Frames
Directory of Open Access Journals (Sweden)
R.S.B. STRAMANDINOLI
Full Text Available Abstract In this work, a two-dimensional finite element (FE model for physical and geometric nonlinear analysis of reinforced concrete beams and plane frames, developed by the authors, is presented. The FE model is based on the Euler-Bernoulli Beam Theory, in which shear deformations are neglected. The bar elements have three nodes with a total of seven degrees of freedom. Three Gauss-points are utilized for the element integration, with the element section discretized into layers at each Gauss point (Fiber Model. It is assumed that concrete and reinforcing bars are perfectly bonded, and each section layer is assumed to be under a uniaxial stress-state. Nonlinear constitutive laws are utilized for both concrete and reinforcing steel layers, and a refined tension-stiffening model, developed by the authors, is included. The Total Lagrangean Formulation is adopted for geometric nonlinear consideration and several methods can be utilized to achieve equilibrium convergence of the nonlinear equations. The developed model is implemented into a computer program named ANEST/CA, which is validated by comparison with some tests on RC beams and plane frames, showing an excellent correlation between numerical and experimental results.
Zhang, Lifu; Li, Chuxin; Zhong, Haizhe; Xu, Changwen; Lei, Dajun; Li, Ying; Fan, Dianyuan
2016-06-27
We have investigated the propagation dynamics of super-Gaussian optical beams in fractional Schrödinger equation. We have identified the difference between the propagation dynamics of super-Gaussian beams and that of Gaussian beams. We show that, the linear propagation dynamics of the super-Gaussian beams with order m > 1 undergo an initial compression phase before they split into two sub-beams. The sub-beams with saddle shape separate each other and their interval increases linearly with propagation distance. In the nonlinear regime, the super-Gaussian beams evolve to become a single soliton, breathing soliton or soliton pair depending on the order of super-Gaussian beams, nonlinearity, as well as the Lévy index. In two dimensions, the linear evolution of super-Gaussian beams is similar to that for one dimension case, but the initial compression of the input super-Gaussian beams and the diffraction of the splitting beams are much stronger than that for one dimension case. While the nonlinear propagation of the super-Gaussian beams becomes much more unstable compared with that for the case of one dimension. Our results show the nonlinear effects can be tuned by varying the Lévy index in the fractional Schrödinger equation for a fixed input power.
Nonlinear free vibration control of beams using acceleration delayed-feedback control
International Nuclear Information System (INIS)
Alhazza, Khaled A; Alajmi, Mohammed; Masoud, Ziyad N
2008-01-01
A single-mode delayed-feedback control strategy is developed to reduce the free vibrations of a flexible beam using a piezoelectric actuator. A nonlinear variational model of the beam based on the von Kàrmàn nonlinear type deformations is considered. Using Galerkin's method, the resulting governing partial differential equations of motion are reduced to a system of nonlinear ordinary differential equations. A linear model using the first mode is derived and is used to characterize the damping produced by the controller as a function of the controller's gain and delay. Three-dimensional figures showing the damping magnitude as a function of the controller gain and delay are presented. The characteristic damping of the controller as predicted by the linear model is compared to that calculated using direct long-time integration of a three-mode nonlinear model. Optimal values of the controller gain and delay using both methods are obtained, simulated and compared. To validate the single-mode approximation, numerical simulations are performed using a three-mode full nonlinear model. Results of the simulations demonstrate an excellent controller performance in mitigating the first-mode vibration
International Nuclear Information System (INIS)
Hawileh, Rami A.; El-Maaddawy, Tamer A.; Naser, Mohannad Z.
2012-01-01
Highlights: ► A 3D nonlinear FE model is developed of RC deep beams with web openings. ► We used cohesion elements to simulate bond. ► The developed FE model is suitable for analysis of such complex structures. -- Abstract: This paper aims to develop 3D nonlinear finite element (FE) models for reinforced concrete (RC) deep beams containing web openings and strengthened in shear with carbon fiber reinforced polymer (CFRP) composite sheets. The web openings interrupted the natural load path either fully or partially. The FE models adopted realistic materials constitutive laws that account for the nonlinear behavior of materials. In the FE models, solid elements for concrete, multi-layer shell elements for CFRP and link elements for steel reinforcement were used to simulate the physical models. Special interface elements were implemented in the FE models to simulate the interfacial bond behavior between the concrete and CFRP composites. A comparison between the FE results and experimental data published in the literature demonstrated the validity of the computational models in capturing the structural response for both unstrengthened and CFRP-strengthened deep beams with openings. The developed FE models can serve as a numerical platform for performance prediction of RC deep beams with openings strengthened in shear with CFRP composites.
International Nuclear Information System (INIS)
Mironova-Ulmane, N.; Pavlenko, A.; Zvagule, T.; Karner, T.; Bruvere, R.; Volrate, A.
2001-01-01
Full text: About 6500 Latvian inhabitants were recruited for clean-up works at Chernobyl Nuclear Power Plant during 1986-1991. Absorbed doses for them are usually unknown, because only less then half of the clean-up workers cohort had officially documented external exposure. Clinical investigations show high morbidity rate of clean-up workers compared with general population. The results of Electronic Spin Resonance (ESR) dose reconstruction (doses absorbed in the tooth enamel) for the clean-up workers were always higher as documented of exposure doses of physical measurements. In many cases more than half of total absorbed dose is due to 90 Sr accumulated in teeth. Most of the clean-up workers have poli-symptomatic sicknesses that exhibit tendency to progress, and their morbidity exceeds that observed in general population. ESR dosimetry programs and clinical follow-up improved existing knowledge in the field of radiation medicine. These data will help to develop and apply the proper treatment and rehabilitation procedures for clean-up workers. (author)
International Nuclear Information System (INIS)
Lazutka, R. J.; Ridmeika, G. J.
2006-01-01
Chromosomal damage and health status were analyzed in Chernobyl clean-up workers currently residing in Lithuania. Statistically significantly (P < 0.05) increased frequencies of chromosome-type aberrations (chromosome breaks, dicentric and ring chromosomes) as well as aberrant cells were found in the peripheral blood lymphocytes of clean-up workers when measured 6-8 years after the exposure. Significant health impairment was characteristic of these persons as well. On average, 5.6 diseases per patient were diagnosed in clean-up workers suffering from cardiovascular diseases. This high co-morbidity resulted in quite high rates of metabolic syndrome (16.7%). Among Chernobyl clean-up workers that had experienced post-traumatic stress disorder, 76% suffered from highly expressed sleep disturbances. Analysis of thyroid diseases among 500 clean-up workers has revealed that 27.6% individuals have different pathology of thyroid gland. Thus, even 20 years after the Chernobyl disaster, clean-up workers must be considered as a group of primary interest both for researchers and physicians. (author)
Numerical investigation of beam-driven PWFA in quasi-nonlinear regime
International Nuclear Information System (INIS)
Londrillo, P.; Gatti, C.; Ferrario, M.
2014-01-01
In beam-driven Plasma Based Wakefield Acceleration (PWFA), the quasi-nonlinear model has been designed to combine high efficient ‘blowout’ regimes, where cold and overdense driving electron beams form a totally rarefied plasma channel, with low charge beam distribution assuring the excited wakefield preserves relevant linear properties. This scheme can have applications in experimental facilities, like SPARC 150 MeV linac at LNF-INFN laboratories, where low-emittance, low-charge narrow electron beams can be produced to be injected on a preformed plasma channel. Here we present a preliminary numerical investigation of this configuration, using the fully 3D ALaDyn PIC code, as a preparatory work to design optimal conditions for the COMB experimental set-up. Specific numerical tools, having computational and diagnostic advantages in PWFA conditions and checks of the numerical outcomes with analytical results, are also presented and discussed
Instability and dynamics of two nonlinearly coupled intense laser beams in a quantum plasma
International Nuclear Information System (INIS)
Wang Yunliang; Shukla, P. K.; Eliasson, B.
2013-01-01
We consider nonlinear interactions between two relativistically strong laser beams and a quantum plasma composed of degenerate electron fluids and immobile ions. The collective behavior of degenerate electrons is modeled by quantum hydrodynamic equations composed of the electron continuity, quantum electron momentum (QEM) equation, as well as the Poisson and Maxwell equations. The QEM equation accounts the quantum statistical electron pressure, the quantum electron recoil due to electron tunneling through the quantum Bohm potential, electron-exchange, and electron-correlation effects caused by electron spin, and relativistic ponderomotive forces (RPFs) of two circularly polarized electromagnetic (CPEM) beams. The dynamics of the latter are governed by nonlinear wave equations that include nonlinear currents arising from the relativistic electron mass increase in the CPEM wave fields, as well as from the beating of the electron quiver velocity and electron density variations reinforced by the RPFs of the two CPEM waves. Furthermore, nonlinear electron density variations associated with the driven (by the RPFs) quantum electron plasma oscillations obey a coupled nonlinear Schrödinger and Poisson equations. The nonlinearly coupled equations for our purposes are then used to obtain a general dispersion relation (GDR) for studying the parametric instabilities and the localization of CPEM wave packets in a quantum plasma. Numerical analyses of the GDR reveal that the growth rate of a fastest growing parametrically unstable mode is in agreement with the result that has been deduced from numerical simulations of the governing nonlinear equations. Explicit numerical results for two-dimensional (2D) localized CPEM wave packets at nanoscales are also presented. Possible applications of our investigation to intense laser-solid density compressed plasma experiments are highlighted.
Energy Technology Data Exchange (ETDEWEB)
Lee, S. Y. [Indiana Univ., Bloomington, IN (United States)
2014-04-07
We had carried out a design of an ultimate storage ring with beam emittance less than 10 picometer for the feasibility of coherent light source at X-ray wavelength. The accelerator has an inherent small dynamic aperture. We study method to improve the dynamic aperture and collective instability for an ultimate storage ring. Beam measurement and accelerator modeling are an integral part of accelerator physics. We develop the independent component analysis (ICA) and the orbit response matrix method for improving accelerator reliability and performance. In collaboration with scientists in National Laboratories, we also carry out experimental and theoretical studies on beam dynamics. Our proposed research topics are relevant to nuclear and particle physics using high brightness particle and photon beams.
Remediation of uranium contaminated sites: clean-up activities in Serbia
International Nuclear Information System (INIS)
Raicevic, S.; Raicevic, J. . E-mail address of corresponding author: raich@beotel.yu; Raicevic, S.)
2005-01-01
One of the serious environmental problems in Serbia represent sites contaminated with depleted uranium (DU) during past war activities. According to UNEP reports and our findings there are two types of contamination: (i) localized points of high, concentrated contamination where DU penetrators enter the soil, and (ii) low level of widespread DU contamination, which indicates that during the conflict DU dust was dispersed into the environment. Remediation of these sites is an urgent need because they represent a permanent threat to the population living in this area. Here we give a brief description of approaches commonly used in remediation of DU contaminated sites, and an overview of current clean-up activities performed in Serbia. (author)
Coolant clean-up system in the primary coolant circuit for nuclear reactor
International Nuclear Information System (INIS)
Saito, Michio.
1981-01-01
Purpose: To maintain the quality of coolants at a prescribed level by distillating coolants in the primary coolant circuit for a BWR type reactor to remove impurities therefrom, taking out the condensates from the top of the distillation column and extracting impurities in a concentrated state from the bottom. Constitution: Coolant water for cooling the core is recycled by a recycling pump by way of a recycling pipeway in a reactor. The coolants extracted from an extraction pipeway connected to the recycling pipeway are fed into a distillation column, where distillation is taken place. Impurities in the coolants, that is, in-core corrosion products, fission products generated in the reactor core, etc. are separated by the distillation, concentrated and solidified in the bottom of the distillation column. While on the other hand, condensates removed with the impurities, that is, coolants cleaned-up are recycled to the coolant water for cooling the reactor core. (Moriyama, K.)
Energy Technology Data Exchange (ETDEWEB)
Tsang, B.; Shaikh, A.A. [EBA Engineering Consultants Ltd., Calgary, AB (Canada)
2006-07-01
Predictive modelling and monitoring natural attenuation to save remedial costs in cleaning up a salt spill were discussed with reference to a site located in central Alberta, as well as a pipeline break in 2002 from a corroded pipe which resulted in a large spill of produced water and oil. Remedial alternatives and an assessment of the site were presented. This included an electromagnetic survey in 2004, groundwater flow regime, soil and groundwater quality data, vegetation survey, and predictive modelling versus observed water quality. Photos and illustrations of the site from the air were provided. A conceptual salt leaching and transport model was proposed as a solution. Model calculation results were also presented. Last, the presentation discussed some important considerations for predictive modeling and next steps for the site. These included continued monitoring, implementation of a restoration plan and engagement of stakeholders such as Alberta Environment and the site landowner. tabs., figs.
Follow-up of CRNL employees involved in the NRX reactor clean-up
International Nuclear Information System (INIS)
Werner, M.M.; Myers, D.K.; Morrison, D.P.
1982-07-01
Data available to date on the mortality of continuing and retired employees of the Chalk River Nuclear Laboratories are consistent with the Σhealthy workerΣ effect that has been observed in similar studies at other nuclear facilities. Because of an accident at the NRX research reactor in December 1952, the reactor was largely dismantled and rebuilt in 1953-54. These operations involved appreciable radiation exposures to a number of employees. The follow-up of the 850 on-site AECL staff involved in the clean-up has indicated that there were no unusual patterns in the mortality of this group when compared with those of the general population of Ontario
Social and psychological state of the Chornobyl clean up workers. Risk factors for negative changes.
Buzunov, V O; Loganovsky, K N; Krasnikova, L I; Bomko, M O; Belyaev, Yu M; Yaroshenko, Zh S; Domashevska, T Ye
2016-12-01
It is generally recognized that the Chornobyl nuclear accident caused strong psychosocial stress affecting the entire population of Ukraine, primarily people involved in recovery operations. But what are the reasons? What is the struc ture of stressors? What are their social, medical and biological consequences, what are strategy and preventive meas ures? Issues that require special research and development. To study social and psychological state of the Chornobyl cleanup workers 1986-1987, and to determine regularities of changes and dangerous risk factors. On the basis of Polyclinic of Radiation Registry, NRCRM, we conducted sample epidemiolog ical study of social and psychological state of the Chornobyl clean up workers 1986-1987. We used method of inter viewing based on «questionnaire», specially developed for this purpose. The study was conducted in October 2013 - May 2015. The sample numbered 235 males aged 18-50 at the time of the accident. Their average age was (31.3 ± 5.3) years at the time of the accident and (58.9 ± 5.3) at the time of survey. The results revealed that the Chornobyl nuclear accident and its consequences caused strong social and psychological stress among clean up workers 1986-1987. We have identified a set of factors closely related to the Chornobyl accident, they have caused a sustainable development of mental syndrome - «Anxiety about their own health and the health of family members, especially children». The other set of stressors which are not closely relat ed to the Chornobyl accident but are the result of the social and economic, social and political situation in the coun try. However the former was found to be the cause of such a psychological state as «dissatisfaction with the com pleteness and quality of life». Social and psychological state of the Chornobyl clean up workers 1986-1987 is estimated as «poor» and it integrally can be characterized as a state of chronic psychosocial stress. Mental syndrome
Studies of leukemia and thyroid disease among Chernobyl clean-up workers from the Baltics
International Nuclear Information System (INIS)
Inskip, P.D.; Tekkel, M.; Rahu, M.
1997-01-01
Following the reactor accident at Chernobyl in late April of 1986, hundreds of thousands of men from throughout the former Soviet Union were sent to Chernobyl to entomb the damaged reactor, remove radioactive debris, and help decontaminate the local environment. They remained for an average of three months and were allowed to accumulate up to 25 cGy of radiation before being sent home. Doses for some workers may have exceeded the allowable limit. The experience of Chernobyl clean-up workers is potentially informative about cancer risk associated with protracted exposure to low levels of radiation. Cohorts of clean-up workers from the Baltic Republics were assembled for study, based on military records and other lists. The study population includes 4,833 men from Estonia 5,709 from Latvia and at least 5,446 from Lithuania, where a pilot study is underway. They are being monitored for cancer incidence through linkages with the corresponding national cancer registries. Biodosimetric assays, including fluorescent in situ hybridization (FISH) for chromosome translocation analysis and the glycophorin A (GPA) somatic cell mutation assay, are being used to supplement information about radiation doses from worker records and questionnaires. Thyroid screening examinations, including palpation, ultrasound and, selectively, fine-needle aspiration biopsies were performed on nearly 2,000 workers in the Estonian cohort (mean age, 40 y) during the spring of 1995, nine years after the reactor accident. The study is still in progress. Work began first in Estonia, and results presented here pertain to this subgroup except as otherwise noted. The average age at the time of arrival at Chernobyl was 31 years. 62% were sent in 1986. Possible reasons for the apparent absence or rarity of radiation-induced thyroid nodules include low and protracted doses, low susceptibility among men exposed as adults, and insufficient passage of time since the accident
Management and disposal of radioactive waste from clean-up operations
International Nuclear Information System (INIS)
Lehto, J.
1997-01-01
Clean-up of large contaminated areas may create enormous amounts of radioactive waste which need to be safely disposed of. Disposal of the waste may include pre-treatment and transportation to a final repository. There is much experience of the removal and disposal of large amounts of radioactive contaminated material from uranium mill tailings sites. For example, in Salt Lake City, USA, two million tons of radium-containing waste was transported 140 km by rail to a disposal site. In Port Hope, Canada, 70,000 cubic meters of similar waste were moved by road to a disposal site 350 km away. The disposal of the uranium mill tailings can be pre-planned, but an accident situation is quite different. In an emergency, decisions on how to deal with the waste from the clean-up may have to be made rapidly and disposal options may be limited. After the Chernobyl accident, large amounts of contaminated material (mainly soil and trees) were disposed of in shallow pits and surface mounds. Overall, approximately 4x10 6 m 3 of waste were distributed between about 800 disposal sites. Because the amounts of waste after a major nuclear accident could be large, their final disposal may require large human and capital resources. Depending on the scale it is possible that the wastes will have to be placed in several final disposal sites. These are likely to be pits or surface mounds. Such repositories may need clay or concrete liners to prevent migration of the radionuclides from the disposal sites. (EG)
Enamel Surface Roughness after Debonding of Orthodontic Brackets and Various Clean-Up Techniques
Directory of Open Access Journals (Sweden)
Farzaneh Ahrari
2013-01-01
Full Text Available Objective: This study aimed to evaluate enamel roughness after adhesive removal using different burs and an Er:YAG laser.Materials and Methods: The buccal surfaces of forty human premolars were sealed by two layers of nail varnish, except for a circular area of 3 mm in diameter on the middle third. The enamel surfaces were initially subjected to profilometry analysis and four parameters of surface irregularity (Ra, Rq, Rt and Rz were recorded. Following bracket bonding and debonding, adhesive remnants were removed by tungsten carbide burs in low- or high- speed handpieces (group 1 and 2, respectively, an ultrafine diamond bur (group 3 or an Er:YAG laser (250 mJ, long pulse, 4 Hz (group 4, and surface roughness parameters were measured again. Then, the buccal surfaces were polished and the third profilometry measurements were performed.Results: The specimens that were cleaned with a low speed tungsten carbide bur showed no significant difference in surface irregularity between the different treatment stages (p>0.05. Surface roughness increased significantly after clean-up with the diamond bur and the Er:YAG laser (p<0.01. In comparison between groups, adhesive removal with tungsten carbide burs at slow- or high-speed handpieces produced the lowest, while enamel clean-up with the Er:YAG laser caused the highest values of roughness measurements (P<0.05.Conclusion: Under the study conditions, application of the ultrafine diamond bur or the Er:YAG laser caused irreversible enamel damage on tooth surface, and thus these methods could not be recommended for removing adhesive remnants after debonding of orthodontic brackets.
Nonlinear focal shift beyond the geometrical focus in moderately focused acoustic beams.
Camarena, Francisco; Adrián-Martínez, Silvia; Jiménez, Noé; Sánchez-Morcillo, Víctor
2013-08-01
The phenomenon of the displacement of the position along the axis of the pressure, intensity, and radiation force maxima of focused acoustic beams under increasing driving voltages (nonlinear focal shift) is studied for the case of a moderately focused beam. The theoretical and experimental results show the existence of this shift along the axis when the initial pressure in the transducer increases until the acoustic field reaches the fully developed nonlinear regime of propagation. Experimental data show that at high amplitudes and for moderate focusing, the position of the on-axis pressure maximum and radiation force maximum can surpass the geometrical focal length. On the contrary, the on-axis pressure minimum approaches the transducer under increasing driving voltages, increasing the distance between the positive and negative peak pressure in the beam. These results are in agreement with numerical KZK model predictions and the existed data of other authors and can be explained according to the effect of self-refraction characteristic of the nonlinear regime of propagation.
Directory of Open Access Journals (Sweden)
Vahid Reza Afkhami
2017-12-01
Full Text Available In the steel frames, beam-column connections are traditionally assumed to be rigid or pinned, but in the steel frames, most types of beam-column connections are semi-rigid. Recent studies and some new codes, especially EC3 and EC4, include methods and formulas to estimate the resistance and stiffness of the panel zone. Because of weaknesses of EC3 and EC4 in some cases, Bayo et al. proposed a new component-based method (cruciform element method to model internal and external semi-rigid connections that revived and modified EC methods. The nonlinear modelling of structures plays an important role in the analysis and design of structures and nonlinear static analysis is a rather simple and efficient technique for analysis of structures. This paper presents nonlinear static (pushover analysis technique by new nonlinearity factor and Bayo et al. model of two types of semi-rigid connections, end plate connection and top and seat angles connection. Two types of lateral loading, uniform and triangular distributions are considered. Results show that the frames with top and seat angles connection have fewer initial stiffness than frames with semi-rigid connection and P-Δ effect more decreases base shear capacity in the case of top and seat angles connection. P-Δ effect in decrease of base shear capacity increases with the increase of number of stories.
Efficiency enhancement in IGCC power plants with air-blown gasification and hot gas clean-up
International Nuclear Information System (INIS)
Giuffrida, Antonio; Romano, Matteo C.; Lozza, Giovanni
2013-01-01
Air-blown IGCC systems with hot fuel gas clean-up are investigated. In detail, the gas clean-up station consists of two reactors: in the first, the raw syngas exiting the gasifier and passed through high-temperature syngas coolers is desulfurized by means of a zinc oxide-based sorbent, whereas in the second the sulfided sorbent is duly regenerated. The hot fuel gas clean-up station releases H 2 S-free syngas, which is ready to fuel the combustion turbine after hot gas filtration, and a SO 2 -laden stream, which is successively treated in a wet scrubber. A thermodynamic analysis of two air-blown IGCC systems, the first with cold fuel gas clean-up and the second with hot fuel gas clean-up, both with a state-of-the-art combustion turbine as topping cycle, shows that it is possible to obtain a really attractive net efficiency (more than 51%) for the second system, with significant improvements in comparison with the first system. Nevertheless, higher efficiency is accomplished with a small reduction in the power output and no sensible efficiency improvements seem to be appreciated when the desulfurization temperature increases. Other IGCC systems, with an advanced 1500 °C-class combustion turbine as the result of technology improvements, are investigated as well, with efficiency as high as 53%. - Highlights: ► Hot fuel gas clean-up is a highly favorable technology for IGCC concepts. ► Significant IGCC efficiency improvements are possible with hot fuel gas clean-up. ► Size reductions of several IGCC components are possible. ► Higher desulfurization temperatures do not sensibly affect IGCC efficiency. ► IGCC efficiency as high as 53% is possible with a 1500°C-class combustion turbine
Nonlinear analysis of reinforced concrete beam with/without tension stiffening effect
International Nuclear Information System (INIS)
Dede, T.; Ayvaz, Y.
2009-01-01
The aim of this paper is to do materially nonlinear failure analysis of RC beam by using finite element method. In the finite element modeling, two different approaches and different tension stress-strain models with/without tension stiffening effect are used by considering two different mesh sizes. In the first approach, the material matrices of concrete and reinforcement are constructed separately, and then superimposed to obtain the element stiffness matrix. In the second approach, the reinforcement is assumed to be uniformly distributed throughout the beam. So, the beam is modeled as a single composite element with increasing the modulus of elasticity of concrete by considering the reinforcement ratio. For these two approaches, elastic-perfectly plastic stress-strain relationship is used for concrete in compression. For the concrete in tension, a stress-strain relationship with/without tension stiffening is used. It is concluded that the approaches and the models considered in this study can be effectively used in the materially nonlinear analysis of RC beams.
International Nuclear Information System (INIS)
Newberger, B.S.; Thode, L.E.
1979-05-01
Experiments on the two-stream instability of a relativistic electron beam propagating through a neutral gas, carried out with the Lawrence Livermore Laboratory Astron beam, have been analyzed using a nonlinear saturation model for a cold beam. The behavior of the observed microwave emission due to the instability is in good agreement with that of the beam energy loss. Collisions on the plasma electrons weaken the nonlinear state of the instability but do not stabilize the mode. The beam essentially acts as if it were cold, a result substantiated by linear theory for waves propagating along the beam. In order to predict the effect of both beam momentum scatter and plasma electron collisions on the stability of the mode in future experiments a full two-dimensional linear theory must be developed
Stabilization of exact nonlinear Timoshenko beams in space by boundary feedback
Do, K. D.
2018-05-01
Boundary feedback controllers are designed to stabilize Timoshenko beams with large translational and rotational motions in space under external disturbances. The exact nonlinear partial differential equations governing motion of the beams are derived and used in the control design. The designed controllers guarantee globally practically asymptotically (and locally practically exponentially) stability of the beam motions at the reference state. The control design, well-posedness and stability analysis are based on various relationships between the earth-fixed and body-fixed coordinates, Sobolev embeddings, and a Lyapunov-type theorem developed to study well-posedness and stability for a class of evolution systems in Hilbert space. Simulation results are included to illustrate the effectiveness of the proposed control design.
International Nuclear Information System (INIS)
Kurjane, N.; Zvagule, T.; Curbakova, E.; Bruvere, R.; Romanova, T.; Sitova, O; Hagina, E.; Socnevs, A.
2001-01-01
No differences in the number of immunologically competent cells and other immunological variables were found among the clean-up workers, depending on the time they were in Chernobyl. However, a statistically significant reduction in the number of CD3+, CD4+, CD16+ and CD19+, decrease in the levels of IgG and suppression of APH and the phagocytic activity of neutrophils with a simultaneous increase in the levels of IgA and C3d was found in all clean-up workers when compared to controls. In a small group of clean-up workers, the levels of some plasma cytokines were detected. A statistically significant increase in IL-6 levels was found in the clean-up workers when compared to controls. The irradiation received by the Chernobyl accident clean-up workers was large enough to cause disturbances in the function of cells and organ systems through immune system disorders with a resultant weakening of the body response and adaptation mechanisms. (authors)
Energy Technology Data Exchange (ETDEWEB)
Hayes, Timothy [Los Alamos National Laboratory, Carlsbad Operations Group (United States); Nelson, Roger [Department Of Energy, Carlsbad Operations Office (United States)
2012-07-01
The Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) manages defense nuclear material that has been determined to be excess to programmatic needs and declared waste. When these wastes contain plutonium, they almost always meet the definition of defense transuranic (TRU) waste and are thus eligible for disposal at the Waste Isolation Pilot Plant (WIPP). The DOE operates the WIPP in a manner that physical protections for attractiveness level D or higher special nuclear material (SNM) are not the normal operating condition. Therefore, there is currently a requirement to terminate safeguards before disposal of these wastes at the WIPP. Presented are the processes used to terminate safeguards, lessons learned during the termination process, and how these approaches might be useful for future defense TRU waste needing safeguards termination prior to shipment and disposal at the WIPP. Also described is a new criticality control container, which will increase the amount of fissile material that can be loaded per container, and how it will save significant taxpayer dollars. Retrieval, compliant packaging and shipment of retrievably stored legacy TRU waste has dominated disposal operations at WIPP since it began operations 12 years ago. But because most of this legacy waste has successfully been emplaced in WIPP, the TRU waste clean-up focus is turning to newly-generated TRU materials. A major component will be transuranic SNM, currently managed in safeguards-protected vaults around the weapons complex. As DOE and NNSA continue to consolidate and shrink the weapons complex footprint, it is expected that significant quantities of transuranic SNM will be declared surplus to the nation's needs. Safeguards termination of SNM varies due to the wide range of attractiveness level of the potential material that may be directly discarded as waste. To enhance the efficiency of shipping waste with high TRU fissile content to WIPP, DOE designed an
Laser damage metrology in biaxial nonlinear crystals using different test beams
Hildenbrand, Anne; Wagner, Frank R.; Akhouayri, Hassan; Natoli, Jean-Yves; Commandre, Mireille
2008-01-01
Laser damage measurements in nonlinear optical crystals, in particular in biaxial crystals, may be influenced by several effects proper to these materials or greatly enhanced in these materials. Before discussion of these effects, we address the topic of error bar determination for probability measurements. Error bars for the damage probabilities are important because nonlinear crystals are often small and expensive, thus only few sites are used for a single damage probability measurement. We present the mathematical basics and a flow diagram for the numerical calculation of error bars for probability measurements that correspond to a chosen confidence level. Effects that possibly modify the maximum intensity in a biaxial nonlinear crystal are: focusing aberration, walk-off and self-focusing. Depending on focusing conditions, propagation direction, polarization of the light and the position of the focus point in the crystal, strong aberrations may change the beam profile and drastically decrease the maximum intensity in the crystal. A correction factor for this effect is proposed, but quantitative corrections are not possible without taking into account the experimental beam profile after the focusing lens. The characteristics of walk-off and self-focusing have quickly been reviewed for the sake of completeness of this article. Finally, parasitic second harmonic generation may influence the laser damage behavior of crystals. The important point for laser damage measurements is that the amount of externally observed SHG after the crystal does not correspond to the maximum amount of second harmonic light inside the crystal.
Zhang, Jinggui
2018-06-01
In this paper, we investigate the dynamical behaviors of the modulation instability (MI) of copropagating optical beams in fractional coupled nonlinear Schrödinger equations (NLSE) with the aim of revealing some novel properties different from those in the conventional coupled NLSE. By applying the standard linear stability method, we first derive an expression for the gain resulting from the instability induced by cross-phase modulation (CPM) in the presence of the Lévy indexes related to fractional effects. It is found that the modulation instability of copropagating optical beams still occurs even in the fractional NLSE with self-defocusing nonlinearity. Then, the analysis of our results further reveals that such Lévy indexes increase the fastest growth frequency and the bandwidth of conventional instability not only for the self-focusing case but also for the self-defocusing case, but do not influence the corresponding maximum gain. Numerical simulations are performed to confirm theoretical predictions. These findings suggest that the novel fractional physical settings may open up new possibilities for the manipulation of MI and nonlinear waves.
Hanford tank clean up: A guide to understanding the technical issues
International Nuclear Information System (INIS)
Gephart, R.E.; Lundgren, R.E.
1995-01-01
One of the most difficult technical challenges in cleaning up the US Department of Energy's (DOE) Hanford Site in southeast Washington State will be to process the radioactive and chemically complex waste found in the Site's 177 underground storage tanks. Solid, liquid, and sludge-like wastes are contained in 149 single- and 28 double-shelled steel tanks. These wastes contain about one half of the curies of radioactivity and mass of hazardous chemicals found on the Hanford Site. Therefore, Hanford cleanup means tank cleanup. Safely removing the waste from the tanks, separating radioactive elements from inert chemicals, and creating a final waste form for disposal will require the use of our nation's best available technology coupled with scientific advances, and an extraordinary commitment by all involved. The purpose of this guide is to inform the reader about critical issues facing tank cleanup. It is written as an information resource for the general reader as well as the technically trained person wanting to gain a basic understanding about the waste in Hanford's tanks -- how the waste was created, what is in the waste, how it is stored, and what are the key technical issues facing tank cleanup. Access to information is key to better understanding the issues and more knowledgeably participating in cleanup decisions. This guide provides such information without promoting a given cleanup approach or technology use
Dynamic analysis of the CRBRP clean-up system (three stage aqueous scrubber)
International Nuclear Information System (INIS)
Kyi, R.; Bijlani, C.; Fazekas, P.; Dajani, A.
1981-01-01
The CRBRP containment clean-up system design required the determination of the thermal-hydraulic performance of the system during its projected operating cycle. The reduced scale component tests at HEDL provided valuable information about the generic performance of the components; however, due to the limitations of the test facility the exact simulation of the actual CRBRP conditions was not feasible. A computer program was developed to permit dynamic system analysis of the full size air cleaning system. The dynamic system analysis considered the mass and energy balances across each component. In addition to the major filtration system components, the system modeling included the supporting fluid system components such as pumps, tanks and heat exchangers. Variable gas flow, temperature, chemical concentrations, and other system parameters were also modeled. Fission product heat, chemical reaction heat and heat of solution were considered. The analysis results provided sodium hydroxide solution concentrations and temperatures, gas temperatures and other variables at the various components within the air cleaning system for each calculated time interval. The accuracy of the computer modeling was verified by comparing the calculated results with HEDL test data. The comparison indicated a better than +-10% agreement with the test data. The analysis results provided the basis for the selection of the system components
Estimation of health in Chernobyl NPP accident consequences cleaning-up participants
International Nuclear Information System (INIS)
Bebeshko, V.G.; Kovalenko, A.N.; Chomazjuk, I.N.
1997-01-01
Over 11 years period of health observation of Chernobyl Accident's victims permits to make some conclusions. Quantitative changes of peripheral blood and bone marrow cells, changes in ultrastructural organization of hemopoietic cells, disturbance of proliferative activity of hemopoietic and stromal progenitor cells in clean-up workers testify to alterations of functional properties of hemopoiesis. There are high level of T- helpers, early appearance regenerated T-cells, which simultaneously express surface antigens of helpers and supressors, synchronization of proliferative cycle of immunocompetentive cells in these patients. Oppressing of antioxidant protection, stable changes of hormonal maintenance of adaptation and reproduction processes, disturbance of feedback mechanism between effector glands and hypophysis, significant rise of polyamines were determined. Cardiovascular diseases are the principal cause of health disruptions at victims. Neural and psychological diseases, suicidal cases, trauma, death in automobile accidents are rank second and third in structure of morbidity. In structure of chronic nonspecific pulmonary diseases dominated chronic obstructive bronchitis. The adrenergic tonus of vegetative nervous system was seen. The peculiarity of rehabilitation measures is complexness and continuity in-patients, out-patients service and providing facilities in health resorts. (author)
Mississippi mud pie: cleaning up a large land-based oil spill
International Nuclear Information System (INIS)
Vitello, C.
2001-01-01
Clean-up of one of the largest land-based oil spills in the history of the United States near Collins, Mississippi, which occurred in December 1999, is described. The oil spill resulted from a corroded pipeline and had been leaking for several days before it was noticed. By the time the first responders arrived the oil had travelled more than five kilometres to the Leaf River, and 24 kilometers downstream. Oil Gator, a patented material that accelerates the biodegradation of hydrocarbons, was used to remediate most of the soil onsite. The product is of low toxicity; it is not harmful to humans, animals or plant life, nor is it WHMIS or OSHA regulated. It was applied with a Samsung Track hoe with a Rhom rake attachment, a mini bobcat hoe and rototillers. The absorbent was effective and very little vegetation had to be removed except for certain trees that were soaked to the root. The cleanup effort cost about $17 million, used 30 truckloads of sorbent product, ten truckloads less than was initially estimated. After some 18 months the Collins site is now covered by two-foot tall grass. Regular third party monitoring is continuing. photos
Mississippi mud pie: cleaning up a large land-based oil spill
Energy Technology Data Exchange (ETDEWEB)
Vitello, C.
2001-07-01
Clean-up of one of the largest land-based oil spills in the history of the United States near Collins, Mississippi, which occurred in December 1999, is described. The oil spill resulted from a corroded pipeline and had been leaking for several days before it was noticed. By the time the first responders arrived the oil had travelled more than five kilometres to the Leaf River, and 24 kilometers downstream. Oil Gator, a patented material that accelerates the biodegradation of hydrocarbons, was used to remediate most of the soil onsite. The product is of low toxicity; it is not harmful to humans, animals or plant life, nor is it WHMIS or OSHA regulated. It was applied with a Samsung Track hoe with a Rhom rake attachment, a mini bobcat hoe and rototillers. The absorbent was effective and very little vegetation had to be removed except for certain trees that were soaked to the root. The cleanup effort cost about $17 million, used 30 truckloads of sorbent product, ten truckloads less than was initially estimated. After some 18 months the Collins site is now covered by two-foot tall grass. Regular third party monitoring is continuing. photos.
LC-MS/MS determination of tranexamic acid in human plasma after phospholipid clean-up.
Fabresse, Nicolas; Fall, Fanta; Etting, Isabelle; Devillier, Philippe; Alvarez, Jean-Claude; Grassin-Delyle, Stanislas
2017-07-15
Tranexamic acid is a widely used antifibrinolytic drug but its pharmacology and pharmacokinetics remains poorly understood. Owing to the recent knowledge on phospholipid-induced matrix effects during human plasma analysis, our aim was to develop a liquid chromatography-mass spectrometry method for the quantitation of tranexamic acid after efficient sample clean-up. Sample preparation consisted in phospholipid removal and protein precipitation. Hydrophilic interaction liquid chromatography was used and the detection was achieved with multiple reaction monitoring. The method was validated according to the European Medicine Agency guideline in the range 1.0-1000.0μg/mL. The performance of the method was excellent with a precision in the range 1.2-3.0%, an accuracy between 88.4 and 96.6% and a coefficient of variation of the internal standard-normalized matrix factor below 6.7%. This method is suitable for the quantification of tranexamic acid in the wide range of concentrations observed during clinical studies, with all the advantages related to phospholipid removal. Copyright © 2017 Elsevier B.V. All rights reserved.
Cancer incidence and thyroid disease among Estonian Chernobyl clean-up workers
Energy Technology Data Exchange (ETDEWEB)
Auvinen, A; Salomaa, S [eds.; Radiation and Nuclear Safety Authority, Helsinki (Finland); Rahu, M; Veidebaum, T; Tekkel, M [eds.; Inst. of Experimental and Clinical Medicine, Tallinn (Estonia); Hakulinen, T [ed.; Finnish Cancer Registry, Helsinki (Finland); Boice, Jr, J D [ed.; Int. Epidemiology Inst., MD (United States)
1998-09-01
The report describes the development and summarizes the results of the project Cancer incidence and thyroid disease among Estonian Chernobyl clean-up workers. One of the goals of the report is to give research protocols and questionnaires for researchers involved in other studies. Eight previously published articles are also included summarizing the results. The development of the collaboration work of the project is described in the introduction of the report. Epidemiological methods are described in an article complemented by the protocol and English version of the questionnaire administered to all cleanup workers, as well as the data collection form of the thyroid study. The results from biological biodosimetry using both glycophorin A and FISH methods have shown that the radiation doses received by the Chernobyl cleanup workers were relatively low. Thyroid nodularity was not associated with any radiation exposure characteristic in the thyroid screening study. Estonian Chernobyl cleanup workers were followed up for cancer incidence through the Estonian Cancer Registry. No cases of leukemia or thyroid cancer were observed by the end of 1993. It is too early to observe possible effect on other types of cancer. However, mortality from suicides was increased compared with general population. Further follow-up and the extension to other Baltic countries in the future will undoubtedly strengthen the study. There are also plans for future projects covering areas from psychosocial factors to radiation biology
International Nuclear Information System (INIS)
Buzunov, V.; Omelyanetz, N.; Strapko, N.; Ledoschuck, B.; Krasnikova, L.; Kartushin, G.
1996-01-01
The Epidemiologic Studies System for Chernobyl NPP Accident consequences cleaning up participants (CNPP ACCP) health status was worked out and than improving in Ukraine after the CNPP Accident. The State Register of Ukraine both with several other Registers are the organizational, methodological and informational basis here. The ACCP health status worsening ,-was registered in dynamics through the post-accidental period i.e. the nervous system, digestive system, blood circulation system, respiratory system, bone-muscular system, endocrine and genitourinary systems chronic non-tumoral pathology both with mental disorders amount increase. In cohort study the differences of morbidity formation were fixed among emergency workers with different radiation exposure doses. The dependence of leukemia morbidity on presence in 30-km zone duration was noticed, it's access manifested 5 years after the participance in ACC. The ACCP disablement increase with main reason of general somatic diseases, and annual mortality growth are registered. But that doesn't exceed the mortality rate among population of working age in Ukraine
A systematic assessment of the state of hazardous waste clean-up technologies
International Nuclear Information System (INIS)
Berg, M.T.; Reed, B.E.; Gabr, M.
1993-07-01
West Virginia University (WVU) and the US DOE Morgantown Energy Technology Center (METC) entered into a Cooperative Agreement on August 29, 1992 entitled ''Decontamination Systems Information and Research Programs.'' Stipulated within the Agreement is the requirement that WVU submit to METC a series of Technical Progress Report for Year 1 of the Agreement. This report reflects the progress and/or efforts performed on the following nine technical projects encompassed by the Year 1 Agreement for the period of April 1 through June 30, 1993: Systematic assessment of the state of hazardous waste clean-up technologies; site remediation technologies -- drain-enhanced soil flushing (DESF) for organic contaminants removal; site remediation technologies -- in situ bioremediation of organic contaminants; excavation systems for hazardous waste sites; chemical destruction of polychlorinated biphenyls; development of organic sensors -- monolayer and multilayer self-assembled films for chemical sensors; Winfield lock and dam remediation; Assessments of Technologies for hazardous waste site remediation -- non-treatment technologies and pilot scale test facility implementation; and remediation of hazardous sites with stream reforming
Hanford tank clean up: A guide to understanding the technical issues
Energy Technology Data Exchange (ETDEWEB)
Gephart, R.E.; Lundgren, R.E.
1995-12-31
One of the most difficult technical challenges in cleaning up the US Department of Energy`s (DOE) Hanford Site in southeast Washington State will be to process the radioactive and chemically complex waste found in the Site`s 177 underground storage tanks. Solid, liquid, and sludge-like wastes are contained in 149 single- and 28 double-shelled steel tanks. These wastes contain about one half of the curies of radioactivity and mass of hazardous chemicals found on the Hanford Site. Therefore, Hanford cleanup means tank cleanup. Safely removing the waste from the tanks, separating radioactive elements from inert chemicals, and creating a final waste form for disposal will require the use of our nation`s best available technology coupled with scientific advances, and an extraordinary commitment by all involved. The purpose of this guide is to inform the reader about critical issues facing tank cleanup. It is written as an information resource for the general reader as well as the technically trained person wanting to gain a basic understanding about the waste in Hanford`s tanks -- how the waste was created, what is in the waste, how it is stored, and what are the key technical issues facing tank cleanup. Access to information is key to better understanding the issues and more knowledgeably participating in cleanup decisions. This guide provides such information without promoting a given cleanup approach or technology use.
California Conservation Corps trains youth to safely clean up oil spills
International Nuclear Information System (INIS)
Penn, P.
1993-01-01
Initiated in response to environmentally destructive crude oil spills, the California Conservation Corps (CCC) is trained to respond anywhere in California, and beyond. Corpsmembers are provided 32 hours of training to exceed both State and Federal Occupational Health and Safety Administration (OSHA) requirements for worker safety. The CCC responded to the Huntington Beach spill in 1990 and impressed both the private sector and government agencies with the high quality of work performed, the organization and discipline of the responders and the safe manner in which they approached the sensitive environmental cleanup. The program was begun with a $75,000 grant from BP America (British Petroleum), the owner of the oil in the American Trader incident. Following the passage of comprehensive oil spill legislation in California, the California Department of Fish and Game Office of Oil Spill Prevention and Response (OSPR) contracted with the CCC to provide 200 trained oil spill workers for beach cleanup. Subsequently, the Corps has responded along the California coast to a pipeline break at Avila Beach in San Luis Obispo County and cleaned up tar balls in the Monterey area
Nonlinear interaction of a parallel-flow relativistic electron beam with a plasma
International Nuclear Information System (INIS)
Jungwirth, K.; Koerbel, S.; Simon, P.; Vrba, P.
1975-01-01
Nonlinear evolution of single-mode high-frequency instabilities (ω approximately ksub(parallel)vsub(b)) excited by a parallel-flow high-current relativistic electron beam in a magnetized plasma is investigated. Fairly general dimensionless equations are derived. They describe both the temporal and the spatial evolution of amplitude and phase of the fundamental wave. Numerically, the special case of excitation of the linearly most unstable mode is solved in detail assuming that the wave energy dissipation is negligible. Then the strength of interaction and the relativistic properties of the beam are fully respected by a single parameter lambda. The value of lambda ensuring the optimum efficiency of the wave excitation as well as the efficiency of the self-acceleration of some beam electrons at higher values of lambda>1 are determined in the case of a fully compensated relativistic beam. Finally, the effect of the return current dissipation is also included (phenomenologically) into the theoretical model, its role for the beam-plasma interaction being checked numerically. (J.U.)
International Nuclear Information System (INIS)
Kong, Ling-Bao; Wang, Hong-Yu; Hou, Zhi-Ling; Jin, Hai-Bo; Du, Chao-Hai
2013-01-01
The nonlinear theory of slow-wave electron cyclotron masers (ECM) with an initially straight electron beam is developed. The evolution equation of the nonlinear beam electron energy is derived. The numerical studies of the slow-wave ECM efficiency with inclusion of Gaussian beam velocity spread are presented. It is shown that the velocity spread reduces the interaction efficiency. -- Highlights: •The theory of slow-wave electron cyclotron masers is considered. •The calculation of efficiency under the resonance condition is presented. •The efficiency under Gaussian velocity spreads has been obtained
Energy Technology Data Exchange (ETDEWEB)
Kong, Ling-Bao, E-mail: konglingbao@gmail.com [School of Science, Beijing University of Chemical Technology, Beijing 100029 (China); Beijing Key Laboratory of Environmentally Harmful Chemicals Assessment, Beijing University of Chemical Technology, Beijing 100029 (China); Wang, Hong-Yu [School of Physics, Anshan Normal University, Anshan 114005 (China); Hou, Zhi-Ling, E-mail: houzl@mail.buct.edu.cn [School of Science, Beijing University of Chemical Technology, Beijing 100029 (China); Beijing Key Laboratory of Environmentally Harmful Chemicals Assessment, Beijing University of Chemical Technology, Beijing 100029 (China); Jin, Hai-Bo [School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Du, Chao-Hai [Institute of Electronics, Chinese Academy of Sciences, Beijing 100190 (China)
2013-12-15
The nonlinear theory of slow-wave electron cyclotron masers (ECM) with an initially straight electron beam is developed. The evolution equation of the nonlinear beam electron energy is derived. The numerical studies of the slow-wave ECM efficiency with inclusion of Gaussian beam velocity spread are presented. It is shown that the velocity spread reduces the interaction efficiency. -- Highlights: •The theory of slow-wave electron cyclotron masers is considered. •The calculation of efficiency under the resonance condition is presented. •The efficiency under Gaussian velocity spreads has been obtained.
Derivation of nonlinear wave equations for ultrasound beam in nonuniform bubbly liquids
Kanagawa, Tetsuya; Yano, Takeru; Kawahara, Junya; Kobayashi, Kazumichi; Watanabe, Masao; Fujikawa, Shigeo
2012-09-01
Weakly nonlinear propagation of diffracted ultrasound beams in a nonuniform bubbly liquid is theoretically studied based on the method of multiple scales with the set of scaling relations of some physical parameters. It is assumed that the spatial distribution of the number density of bubbles in an initial state at rest is a slowly varying function of space coordinates and the amplitude of its variation is small compared with a mean number density. As a result, a Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation with dispersion and nonuniform effects for a low frequency case and a nonlinear Schrödinger (NLS) equation with dissipation, diffraction, and nonuniform effects for a high frequency case, are derived from the basic equations of bubbly flows.
International Nuclear Information System (INIS)
Larciprete, M.C.; Passeri, D.; Michelotti, F.; Paoloni, S.; Sibilia, C.; Bertolotti, M.; Belardini, A.; Sarto, F.; Somma, F.; Lo Mastro, S.
2005-01-01
We investigated second order optical nonlinearity of zinc oxide thin films, grown on glass substrates by the dual ion beam sputtering technique under different deposition conditions. Linear optical characterization of the films was carried out by spectrophotometric optical transmittance and reflectance measurements, giving the complex refractive index dispersion. Resistivity of the films was determined using the four-point probe sheet resistance method. Second harmonic generation measurements were performed by means of the Maker fringes technique where the fundamental beam was originated by nanosecond laser at λ=1064 nm. We found a relatively high nonlinear optical response, and evidence of a dependence of the nonlinear coefficient on the deposition parameters for each sample. Moreover, the crystalline properties of the films were investigated by x-ray diffraction measurements and correlation with second order nonlinearity were analyzed. Finally, we investigated the influence of the oxygen flow rate during the deposition process on both the second order nonlinearity and the structural properties of the samples
Quasi-periodic solutions of nonlinear beam equation with prescribed frequencies
Energy Technology Data Exchange (ETDEWEB)
Chang, Jing [College of Information Technology, Jilin Agricultural University, Changchun 130118 (China); Gao, Yixian, E-mail: gaoyx643@nenu.edu.cn; Li, Yong [School of Mathematics and Statistics, and Center for Mathematics and Interdisciplinary Sciences, Northeast Normal University, Changchun 130024 (China)
2015-05-15
Consider the one dimensional nonlinear beam equation u{sub tt} + u{sub xxxx} + mu + u{sup 3} = 0 under Dirichlet boundary conditions. We show that for any m > 0 but a set of small Lebesgue measure, the above equation admits a family of small-amplitude quasi-periodic solutions with n-dimensional Diophantine frequencies. These Diophantine frequencies are the small dilation of a prescribed Diophantine vector. The proofs are based on an infinite dimensional Kolmogorov-Arnold-Moser iteration procedure and a partial Birkhoff normal form. .
Quasi-periodic solutions of nonlinear beam equation with prescribed frequencies
International Nuclear Information System (INIS)
Chang, Jing; Gao, Yixian; Li, Yong
2015-01-01
Consider the one dimensional nonlinear beam equation u tt + u xxxx + mu + u 3 = 0 under Dirichlet boundary conditions. We show that for any m > 0 but a set of small Lebesgue measure, the above equation admits a family of small-amplitude quasi-periodic solutions with n-dimensional Diophantine frequencies. These Diophantine frequencies are the small dilation of a prescribed Diophantine vector. The proofs are based on an infinite dimensional Kolmogorov-Arnold-Moser iteration procedure and a partial Birkhoff normal form.
Directory of Open Access Journals (Sweden)
A. Franchi
2009-01-01
Full Text Available The multiturn extraction from a circular particle accelerator is performed by trapping the beam inside stable islands of the horizontal phase space. In general, by crossing a resonance of order n, n+1 beamlets are created whenever the resonance is stable, whereas if the resonance is unstable the beam is split in n parts. Islands are generated by nonlinear magnetic fields, whereas the trapping is realized by means of a given tune variation so to cross adiabatically a resonance. Experiments at the CERN Proton Synchrotron carried out in 2007 gave the evidence of protons trapped in stable islands while crossing the one-third and one-fifth resonances. Dedicated experiments were also carried out to study the trapping process and its reversibility properties. The results of these measurement campaigns are presented and discussed in this paper.
Franchi, A; Giovannozzi, M; CERN. Geneva. BE Department
2009-01-01
The multi-turn extraction from a circular particle accelerator is performed by trapping the beam inside stable islands of the horizontal phase space. In general, by crossing a resonance of order n, n+1 beamlets are created whenever the resonance is stable, whereas if the resonance is unstable the beam is split in n parts. Islands are generated by non-linear magnetic fields, whereas the trapping is realized by means of a given tune variation so to cross adiabatically a resonance. Experiments at the CERN Proton Synchrotron carried out in 2007 gave the evidence of protons trapped in stable islands while crossing the one-third and one-fifth resonances. Dedicated experiments were also carried out to study the trapping process and its reversibility properties. The results of these measurement campaigns are presented and discussed in this paper.
Nonlinear effects in optical pumping of a cold and slow atomic beam
Porfido, N.
2015-10-12
By photoionizing hyperfine (HF) levels of the Cs state 62P3/2 in a slow and cold atom beam, we find how their population depends on the excitation laser power. The long time (around 180μs) spent by the slow atoms inside the resonant laser beam is large enough to enable exploration of a unique atom-light interaction regime heavily affected by time-dependent optical pumping. We demonstrate that, under such conditions, the onset of nonlinear effects in the population dynamics and optical pumping occurs at excitation laser intensities much smaller than the conventional respective saturation values. The evolution of population within the HF structure is calculated by numerical integration of the multilevel optical Bloch equations. The agreement between numerical results and experiment outcomes is excellent. All main features in the experimental findings are explained by the occurrence of “dark” and “bright” resonances leading to power-dependent branching coefficients.
Cleaning up: environmental services are bound to stay a growth industry
International Nuclear Information System (INIS)
Stonehouse, D.
2000-01-01
Environmental protection regulations with particular regard for the oil and natural gas industry are reviewed. New flaring regulations will be reduced by 70 per cent within the next seven years and remaining flares will operate at nearly 100 per cent efficiency in burning harmful substances. The Canadian Council of Ministers of the Environment (CCME) is currently targeting other emission sources from oilfield equipment. Benzene emissions from glycol dehydrators will be reduced by 90 per cent by 2007. Soil remediation targets are also very ambitious. The standard is 1,000 parts per million of hydrocarbons. As an indication of the difficulties experienced by oil companies in land reclamation, one out of five topsoil replacement and revegetation applications have failed. As a result of these stringent regulations, a multi-billion dollar environmental industry has emerged, constantly searching for better and more cost effective ways to comply with rising standards. The most immediate challenge is to snuff out some 5,300 flare stacks. The science behind environmental protection is still weak and controversial, and satisfactory answers are still some years away; in the meantime oil companies must meet existing requirements, inventing new equipment and approaches in the process. Incineration may be one answer, but alternative approaches are also being investigated. Wellsite reclamation, cleaning up of exhausted fields, identifying and preserving wild animal habitats, protecting endangered species, accounting for human populations and their effects, greenhouse gas emissions and the complex issues of emissions trading and credits are just some of the issues that will ensure that environmental services will continue to be a growth industry
For successfully completed clean-ups treating different kinds of contaminants
Energy Technology Data Exchange (ETDEWEB)
Bachmann, A.; Bentz, R.; Huerzeler, R.A.; Matter, B. [Ciba Specialty Chemicals Inc., Basel (Switzerland)
2003-07-01
In this Special Session 4 remediation projects are presented, that were run in different environments and under different constraints. The projects / sites showed the following characteristics: Amponville (F) This project represents a successful clean up of an uncontrolled dump by drums containing Chlorophenol-wastes from an old agrochemical production site. Contaminated sandy soil had to be excavated and treated in a Thermal Desorption unit on site. An interactive CD-ROM data medium was created for documentation. Niederglatt (CH) A old industrial area contaminated by organics (hydrocarbons, polyaromatics) as well as by chromium Cr(VI) was remediated by soil-excavation. The soil had to be analysed, separated and treated accordingly. Chromium-contaminated material had to be treated physically and chemically. The soil affected by organic pollutants had to be washed off-site. Special attention was given to the water flowing off the site, groundwater control and to dust deposit measures in the near environment. Dielsdorf (CH) This site contained wastes from former Lindane-production, containing HCH, Dinitro-o-Cresol and metals like As, Cu and Pb. The contaminated soil and the wastes had to be excavated, analysed, partly backfilled and the rest treated in different ways. Residual pollutants concentration was calculated following a risk-analysis/mobility-calculation and agreed upon with the authorities before starting the remediation work. Schweizerhalle (CH) A huge fire left an area of contaminated soil that was affected by argo-chemicals and their incineration-products. The most harmful pollutants were mercury and phosphoric esters. After coverage by a tent and lowering of the groundwater level the gravel and the sandy soil was excavated and treated in an on-site large-scale Soil Washing and Treating installation by using surfactants and other reagents to separate the pollutants. Most of the soil could be backfilled on-site. Less than 5% of the soil volume containing
International Nuclear Information System (INIS)
Khomazyuk, Yi.M.; Sidorenko, G.V.
2004-01-01
Correlation of heart rate variability (HRV) and hear left ventricle hypertrophy (LVH) in clean-up workers of Chernobyl accident with essential hypertension was estimated. Lowering of total HRV, parasympathetic and sympathetic activity associated with increased range of LVH was discovered
Roseboom, H.; Hulshoff, A.
1979-01-01
A rapid and simple clean-up and derivatization procedure that can be generally applied to the gas chromatographie (GC) determination of acidic drugs of various chemical and therapeutic classes is described. The drugs are extracted from acidified plasma with chloroform containing 5% of isopropanol,
International Nuclear Information System (INIS)
Simonova, L.Yi.; Rozdyil's'kij, S.Yi.; Kulyinyich, G.V.; Fertman, V.Z.; Krapivnij, O.O.; Abramova, L.P.; Byilogurova, L.V.; Levchenko, A.P.
2001-01-01
The study involved 59 male patients with relapsing duodenal ulcer who had participated in Chernobyl accident clean-up. Laser therapy was administrated daily on the projection of the zone of the ulcer and acupuncture zones. The obtained results allow to conclude that transcutaneous laser therapy is an effective method of treatment of ulcer disease
International Nuclear Information System (INIS)
Zujeva, N.O.; Kovalenko, O.M.; Jefyimov, A.S.
2000-01-01
The clinical and metabolic features of type 2 diabetes mellitus (DM) in the participants of Chernobyl accident clean-up (PCAC) was studied. It was found out that DM in PCAC was first diagnosed against a background of formed cardiovascular pathology and hyper coagulation
International Nuclear Information System (INIS)
Krishan, S.
2007-01-01
The Stieltjes transform has been used in place of a more common Laplace transform to determine the time evolution of the self-consistent field (SCF) of an unmagnetized semi-infinite plasma, where the plasma electrons together with a primary and a low-density secondary electron beam move perpendicular to the boundary surface. The secondary beam is produced when the primary beam strikes the grid. Such a plasma system has been investigated by Griskey and Stanzel [M. C. Grisky and R. L. Stenzel, Phys. Rev. Lett. 82, 556 (1999)]. The physical phenomenon, observed in their experiment, has been named by them as ''secondary beam instability.'' The character of the instability observed in the experiment is not the same as predicted by the conventional treatments--the field amplitude does not grow with time. In the frequency spectrum, the theory predicts peak values in the amplitude of SCF at the plasma frequency of plasma and secondary beam electrons, decreasing above and below it. The Stieltjes transform for functions, growing exponentially in the long time limit, does not exist, while the Laplace transform technique gives only exponentially growing solutions. Therefore, it should be interesting to know the kind of solutions that an otherwise physically unstable plasma will yield. In the high-frequency limit, the plasma has been found to respond to any arbitrary frequency of the initial field differentiated only by the strength of the resulting SCF. The condition required for exponential growth in the conventional treatments, and the condition for maximum amplitude (with respect to frequency) in the present treatment, have been found to be the same. Nonlinear mode coupling between the modes excited by the plasma electrons and the low-density secondary beam gives rise to two frequency-dependent peaks in the field amplitude, symmetrically located about the much stronger peak due to the plasma electrons, as predicted by the experiment
Eglite, M E; Zvagule, T J; Rainsford, K D; Reste, J D; Curbakova, E V; Kurjane, N N
2009-06-01
The health status of some 6,000 workers from Latvia who went to clean-up the Chernobyl Nuclear Power Plant (CNPP) site following the explosion on 26 April 1986 has been analyzed. The data on these workers have been recorded in the Latvian State Register of Occupational disease patients and people exposed to ionizing radiation due to Chernobyl NPP accident (Latvian State Register) that was established in 1994. From these data, estimates have been made of external ionizing radiation to which these workers were exposed together with observations on the impact of exposure to heavy metals (especially lead and zinc) and radioactive isotopes released during the reactor 'meltdown'. These factors along with psycho-emotional and social-economic stresses account for a marked excess of mortality and morbidity in the group of CNPP accident clean-up workers compared with that of the non-exposed normal Latvian population adjusted for age and sex. The number of diseases or conditions in the CNPP accident clean-up workers has progressively risen from an average of 1.3 in 1986 to 10.9 in 2007. This exceeds for the Latvian population when adjusted for age and sex. The most serious conditions affect the nervous, digestive, respiratory, cardiovascular, endocrine (especially thyroid) and immunological systems. While the morbidity associated with diseases of the respiratory and digestive systems has decreased in recent years that in the other systems is increasing. In recent years, there has been an increased occurrence of cancers affecting the thyroid, prostate and stomach. Clinical and laboratory investigations suggest that surviving CNPP accident clean-up workers exhibit signs of immuno-inflammatory reactions causing premature aging with evidence of autoimmune diseases and immunological deficiencies or abnormalities. It is suggested that the CNPP accident clean-up workers may have a specific syndrome, the 'Chernobyl post-radiation neurosomatic polypathy', due to sustained oxidant
Hydrophone area-averaging correction factors in nonlinearly generated ultrasonic beams
International Nuclear Information System (INIS)
Cooling, M P; Humphrey, V F; Wilkens, V
2011-01-01
The nonlinear propagation of an ultrasonic wave can be used to produce a wavefield rich in higher frequency components that is ideally suited to the calibration, or inter-calibration, of hydrophones. These techniques usually use a tone-burst signal, limiting the measurements to harmonics of the fundamental calibration frequency. Alternatively, using a short pulse enables calibration at a continuous spectrum of frequencies. Such a technique is used at PTB in conjunction with an optical measurement technique to calibrate devices. Experimental findings indicate that the area-averaging correction factor for a hydrophone in such a field demonstrates a complex behaviour, most notably varying periodically between frequencies that are harmonics of the centre frequency of the original pulse and frequencies that lie midway between these harmonics. The beam characteristics of such nonlinearly generated fields have been investigated using a finite difference solution to the nonlinear Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation for a focused field. The simulation results are used to calculate the hydrophone area-averaging correction factors for 0.2 mm and 0.5 mm devices. The results clearly demonstrate a number of significant features observed in the experimental investigations, including the variation with frequency, drive level and hydrophone element size. An explanation for these effects is also proposed.
Hydrophone area-averaging correction factors in nonlinearly generated ultrasonic beams
Cooling, M. P.; Humphrey, V. F.; Wilkens, V.
2011-02-01
The nonlinear propagation of an ultrasonic wave can be used to produce a wavefield rich in higher frequency components that is ideally suited to the calibration, or inter-calibration, of hydrophones. These techniques usually use a tone-burst signal, limiting the measurements to harmonics of the fundamental calibration frequency. Alternatively, using a short pulse enables calibration at a continuous spectrum of frequencies. Such a technique is used at PTB in conjunction with an optical measurement technique to calibrate devices. Experimental findings indicate that the area-averaging correction factor for a hydrophone in such a field demonstrates a complex behaviour, most notably varying periodically between frequencies that are harmonics of the centre frequency of the original pulse and frequencies that lie midway between these harmonics. The beam characteristics of such nonlinearly generated fields have been investigated using a finite difference solution to the nonlinear Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation for a focused field. The simulation results are used to calculate the hydrophone area-averaging correction factors for 0.2 mm and 0.5 mm devices. The results clearly demonstrate a number of significant features observed in the experimental investigations, including the variation with frequency, drive level and hydrophone element size. An explanation for these effects is also proposed.
Kharin, Nikolay A.
2001-05-01
The novel solution of the KZK equation for acoustic pressure of the second harmonic in slightly focused beam of a circular transducer was obtained in a closed form for moderately nonlinear absorbing media (Gol'dberg numbers ~ 1). The solution is based on the method of slowly changing wave profile in combination with the method of successive approximations. Two pairs of transducers (Valpey-Fisher Corp.) Were compared to investigate the influence of focusing on the applicability of the moderate nonlinearity approach. The first pair was of 0.25' diameter and the second was of 0.5' diameter. Both pairs has one transducer with flat surface and the other geometrically focused at 4'. The central frequency for all transducers was 5 MHz. Measurements were undertaken in the blood-mimicking solution of water and glycerine. The results demonstrated that for slightly focused transducers with circular apertures, the moderate nonlinearity approach is still valid, as it was proved for flat sources with the same source level, despite the higher pressures in the focal region. The peak pressure for the weakly focused system occurs at a shorter range than focal length.
Furuseth, Sondre
2017-01-01
The performance of high-energy circular hadron colliders, as the Large Hadron Collider, is limited by beam-beam interactions. The strongly nonlinear force between the two opposing beams causes diverging Hamiltonians and resonances, which can lead to a reduction of the lifetime of the beams. The nonlinearity makes the effect of the force difficult to study analytically, even at first order. Numerical models are therefore needed to evaluate the overall effect of different configurations of the machines. This report discusses results from an implementation of the weak-strong model, studying the effects of head-on beam-beam interactions. The assumptions has been shown to be valid for configurations where the growth and losses of the beam are small. The tracking has been done using an original code which applies graphic cards to reduce the computation time. The bunches in the beams have been modelled cylindrically symmetrical, based on a Gaussian distribution in three dimensions. This choice fits well with bunches...
Oak Ridge Cleanup Vision: Moving to the Future by Cleaning Up the Past - 13291
International Nuclear Information System (INIS)
Cange, Susan M.; Wieland, Christopher C.; DePaoli, Susan M.
2013-01-01
received buy-in from the leadership in Headquarters, the regulators, and the community. Issues EM was facing in 2009 are presented. Resulting lessons learned and subsequent changes that the Office has gone through in the past several years in order to improve performance in the safe execution of work, relationships with external stakeholders, and communications both internally and externally are discussed. Results of these efforts are provided as a summary of Program accomplishments, including a strong focus on the future. EM's motto, Moving to the Future by Cleaning up the Past, will be demonstrated through the Program's mission, which includes protecting the region's health and environment; ensuring the continuation of ongoing vital missions being conducted by DOE on the Oak Ridge Reservation; and making clean land available for future use at all three sites, with a near-term focus on Re-industrialization of ETTP. (authors)
UTILIZING INNOVATIVE TECHNOLOGIES FOR ENVIRONMENTAL CLEAN-UP AT SAVANNAH RIVER SITE
International Nuclear Information System (INIS)
Bergren, C.
2009-01-01
The Savannah River Site (SRS) is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River near Aiken, South Carolina. During operations, which started in 1951, hazardous substances (chemicals and radionuclides) were released to the environment. The releases occurred as a result of inadvertent spills and waste disposal in unlined pits and basins which was common practice before environmental regulations existed. The hazardous substances have migrated to the vadose zone and groundwater in many areas of the SRS, resulting in 515 waste units and facilities that are required by environmental regulations, to undergo characterization and, if needed, remediation. In the initial years of the SRS environmental cleanup program (early 1990s), the focus was to use common technologies (such as pump and treat, air stripping, excavation and removal) that actively and tangibly removed contamination. Exclusive use of these technologies required continued and significant funding while often failing to meet acceptable clean-up goals and objectives. Recognizing that a more cost-effective approach was needed, SRS implemented new and complementary remediation methods focused on active and passive technologies targeted to solve specific remediation problems. Today, SRS uses technologies such as chemical/pH-adjusting injection, phytoremediation, underground cutoff walls, dynamic underground stripping, soil fracturing, microbial degradation, baroballs, electrical resistance heating, soil vapor extraction, and microblowers to more effectively treat contamination at lower costs. Additionally, SRS's remediation approach cost effectively maximizes cleanup as SRS works proactively with multiple regulatory agencies. Using GIS, video, animation, and graphics, SRS is able to provide an accurate depiction of the evolution of SRS groundwater and vadose zone cleanup activities to convince stakeholders and regulators of the effectiveness of various cleanup
HYDRAULIC ELEVATOR INSTALLATION ESTIMATION FOR THE WATER SOURCE WELL SAND-PACK CLEANING UP
Directory of Open Access Journals (Sweden)
V. V. Ivashechkin
2016-01-01
Full Text Available The article offers design of a hydraulic elevator installation for cleaning up water-source wells of sand packs. It considerers the installation hydraulic circuit according to which the normal pump feeds the high-level tank water into the borehole through two parallel water lines. The water-jet line with washing nozzle for destroying the sand-pack and the supply pipe-line coupled with the operational nozzle of the hydraulic elevator containing the inlet and the supply pipelines for respectively intaking the hydromixture and removing it from the well. The paper adduces equations for fluid motion in the supply and the water-jet pipelines and offers expressions for evaluating the required heads in them. For determining water flow in the supply and the water-jet pipe lines the author proposes to employ graphical approach allowing finding the regime point in Q–H chart by means of building characteristics of the pump and the pipe-lines. For calculating the useful vertical head, supply and dimensions of the hydraulic elevator the article employs the equation of motion quantity with consistency admission of the motion quantity before and after mixing the flows in the hydraulic elevator. The suggested correlations for evaluating the hydraulic elevator efficiency determine the sand pack removal duration as function of its sizes and the ejected fluid flow rate. A hydraulic-elevator installation parameters estimation example illustrates removing a sand pack from a water-source borehole of 41 m deep and 150 mm diameter bored in the village of Uzla of Myadelsk region, of Minsk oblast. The working efficiency of a manufactured and laboratory tested engineering prototype of the hydraulic elevator installation was acknowledged in actual tests at the indicated borehole site. With application of graphical approach, the suggested for the hydraulic elevator installation parameters calculation procedure allows selecting, with given depth and the borehole diameter
Petruzzelli, Gianniantonio; Pedron, Francesca; Pezzarossa, Beatrice
2013-04-01
Processes of metal bioavailability in the soil To know the bioavailability processes at site specific levels is essential to understand in detail the risks associated with pollution, and to support the decision-making process, i.e. description of the conceptual model and choice of clean up technologies. It is particularly important to assess how chemical, physical and biological processes in the soil affect the reactions leading to adsorption, precipitation or release of contaminants. The measurement of bioavailability One of the main difficulties in the practical application of the bioavailability concept in soil remediation is the lack of consensus on the method to be used to measure bioavailability. The best strategy is to apply a series of tests to assess bioavailability, since no applicable method is universally valid under all conditions. As an example, bioavailability tests for phytotechnology application should consider two distinct aspects: a physico-chemical driven solubilization process and a physiologically driven uptake process. Soil and plant characteristics strongly influence bioavailability. Bioavailability as a tool in remediation strategies Bioavailability can be used at all stages in remediation strategies: development of the conceptual model, evaluation of risk assessment, and selection of the best technology, considering different scenarios and including different environmental objectives. Two different strategies can be followed: the reduction and the increase of bioavailability. Procedures that reduce bioavailability aim to prevent the movement of pollutants from the soil to the living organisms, essentially by: i) removal of the labile phase of the contaminant, i.e. the fraction which is intrinsic to the processes of bioavailability (phytostabilization); ii) conversion of the labile fraction into a stable fraction (precipitation or adsorption); iii) increase of the resistance to mass transfer of the contaminants (inertization). Procedures
Directory of Open Access Journals (Sweden)
Vladimir P. Agapov
2017-01-01
Full Text Available Abstract. Objectives Modern building codes prescribe the calculation of building structures taking into account the nonlinearity of deformation. To achieve this goal, the task is to develop a methodology for calculating prestressed reinforced concrete beams, taking into account physical and geometric nonlinearity. Methods The methodology is based on nonlinear calculation algorithms implemented and tested in the computation complex PRINS (a program for calculating engineering constructions for other types of construction. As a tool for solving this problem, the finite element method is used. Non-linear calculation of constructions is carried out by the PRINS computational complex using the stepwise iterative method. In this case, an equation is constructed and solved at the loading step, using modified Lagrangian coordinates. Results The basic formulas necessary for both the formation and the solution of a system of nonlinear algebraic equations by the stepwise iteration method are given, taking into account the loading, unloading and possible additional loading. A method for simulating prestressing is described by setting the temperature action on the reinforcement and stressing steel rod. Different approaches to accounting for physical and geometric nonlinearity of reinforced concrete beam rods are considered. A calculation example of a flat beam is given, in which the behaviour of the beam is analysed at various stages of its loading up to destruction. Conclusion A program is developed for the calculation of flat and spatially reinforced concrete beams taking into account the nonlinearity of deformation. The program is adapted to the computational complex PRINS and as part of this complex is available to a wide range of engineering, scientific and technical specialists.
The existence of periodic solutions for nonlinear beam equations on Td by a para-differential method
Chen, Bochao; Li, Yong; Gao, Yixian
2018-05-01
This paper focuses on the construction of periodic solutions of nonlinear beam equations on the $d$-dimensional tori. For a large set of frequencies, we demonstrate that an equivalent form of the nonlinear equations can be obtained by a para-differential conjugation. Given the non-resonant conditions on each finite dimensional subspaces, it is shown that the periodic solutions can be constructed for the block diagonal equation by a classical iteration scheme.
Abdi, Mohamad; Hajihasani, Mojtaba; Gharibzadeh, Shahriar; Tavakkoli, Jahan
2012-12-01
Ultrasound waves have been widely used in diagnostic and therapeutic medical applications. Accurate and effective simulation of ultrasound beam propagation and its interaction with tissue has been proved to be important. The nonlinear nature of the ultrasound beam propagation, especially in the therapeutic regime, plays an important role in the mechanisms of interaction with tissue. There are three main approaches in current computational fluid dynamics (CFD) methods to model and simulate nonlinear ultrasound beams: macroscopic, mesoscopic and microscopic approaches. In this work, a mesoscopic CFD method based on the Lattice-Boltzmann model (LBM) was investigated. In the developed method, the Boltzmann equation is evolved to simulate the flow of a Newtonian fluid with the collision model instead of solving the Navier-Stokes, continuity and state equations which are used in conventional CFD methods. The LBM has some prominent advantages over conventional CFD methods, including: (1) its parallel computational nature; (2) taking microscopic boundaries into account; and (3) capability of simulating in porous and inhomogeneous media. In our proposed method, the propagating medium is discretized with a square grid in 2 dimensions with 9 velocity vectors for each node. Using the developed model, the nonlinear distortion and shock front development of a finiteamplitude diffractive ultrasonic beam in a dissipative fluid medium was computed and validated against the published data. The results confirm that the LBM is an accurate and effective approach to model and simulate nonlinearity in finite-amplitude ultrasound beams with Mach numbers of up to 0.01 which, among others, falls within the range of therapeutic ultrasound regime such as high intensity focused ultrasound (HIFU) beams. A comparison between the HIFU nonlinear beam simulations using the proposed model and pseudospectral methods in a 2D geometry is presented.
Directory of Open Access Journals (Sweden)
Chouiyakh H.
2016-01-01
Full Text Available The aim of this work is to investigate the nonlinear forced vibration of beams containing an arbitrary number of cracks and to perform a multi-crack identification procedure based on the obtained signals. Cracks are assumed to be open and modelled trough rotational springs linking two adjacent sub-beams. Forced vibration analysis is performed by a developed time differential quadrature method. The obtained nonlinear vibration responses are analyzed by Huang Hilbert Transform. The instantaneous frequency is used as damage index tool for cracks detection.
Elwakil, S. A.; El-hanbaly, A. M.; Elgarayh, A.; El-Shewy, E. K.; Kassem, A. I.
2014-11-01
The properties of nonlinear electron-acoustic rogue waves have been investigated in an unmagnetized collisionless four-component plasma system consisting of a cold electron fluid, non-thermal hot electrons obeying a non-thermal distribution, an electron beam and stationary ions. It is found that the basic set of fluid equations is reduced to a nonlinear Schrodinger equation. The dependence of rogue wave profiles on the electron beam and energetic population parameter are discussed. The results of the present investigation may be applicable in auroral zone plasma.
DEFF Research Database (Denmark)
Fromberg, Arvid; Højgård, A.; Duedahl-Olesen, Lene
2007-01-01
system equipped with a GPC column (S-X3) and pre-packed silica SPE columns for the subsequent clean-up and finally gas chromatography-mass spectrometry (GC-MS) determination. The method was validated for the determination of PAHs in vegetable oils and it can meet the criteria for the official control...... of benzo[a]pyrene levels in foods laid down by the Commission of the European Communities. A survey of 69 vegetable oils sampled from the Danish market included olive oil as well as other vegetable oils such as rapeseed oil, sunflower oil, grape seed oil and sesame oil. Levels of benzo[a]pyrene in all......A semi-automatic method for the determination of polycyclic aromatic hydrocarbons (PAHs) in edible oils using a combined gel permeation chromatography/solid-phase extraction (GPC/SPE) clean-up is presented. The method takes advantage of automatic injections using a Gilson ASPEC XL sample handling...
International Nuclear Information System (INIS)
Shay, M.R.; Short, S.M.; Stiles, D.L.
1994-03-01
This paper describes the methodologies and data used for estimating the complex-wide impacts of alternative strategies for conducting remediation of all DOE sites and facilities, but does not address issues relating to Waste Management capabilities. Clean-up strategies and their corresponding goals for contaminated media may be driven by concentration-based regulatory standards, land-use standards (e.g., residential, industrial, wild life reserve, or totally restricted), risk-based standards, or other standards determined through stakeholder input. Strategies implemented to achieve these goals usually require the deployment of (a) clean-up technologies to destroy, remove, or contain the contaminants of concern; (b) institutional controls to prevent potential receptors from coming into contact with the contaminants; or (c) a combination of the above
International Nuclear Information System (INIS)
Papon, G.; Marquestaut, N.; Royon, A.; Canioni, L.; Petit, Y.; Dussauze, M.; Rodriguez, V.; Cardinal, T.
2014-01-01
We depict a new approach for the localized creation in three dimensions (3D) of a highly demanded nonlinear optical function for integrated optics, namely second harmonic generation. We report on the nonlinear optical characteristics induced by single-beam femtosecond direct laser writing in a tailored silver-containing phosphate glass. The original spatial distribution of the nonlinear pattern, composed of four lines after one single laser writing translation, is observed and modeled with success, demonstrating the electric field induced origin of the second harmonic generation. These efficient second-order nonlinear structures (with χ eff (2) ∼ 0.6 pm V −1 ) with sub-micron scale are impressively stable under thermal constraint up to glass transition temperature, which makes them very promising for new photonic applications, especially when 3D nonlinear architectures are desired
Oak Ridge Cleanup Vision: Moving to the Future by Cleaning Up the Past - 13291
Energy Technology Data Exchange (ETDEWEB)
Cange, Susan M. [DOE Oak Ridge, P.O. Box 2001, Oak Ridge, TN 37831 (United States); Wieland, Christopher C.; DePaoli, Susan M. [Pro2Serve, 1100 Bethel Valley Rd., Oak Ridge, TN 37830 (United States)
2013-07-01
successfully revised Program priorities and has received buy-in from the leadership in Headquarters, the regulators, and the community. Issues EM was facing in 2009 are presented. Resulting lessons learned and subsequent changes that the Office has gone through in the past several years in order to improve performance in the safe execution of work, relationships with external stakeholders, and communications both internally and externally are discussed. Results of these efforts are provided as a summary of Program accomplishments, including a strong focus on the future. EM's motto, Moving to the Future by Cleaning up the Past, will be demonstrated through the Program's mission, which includes protecting the region's health and environment; ensuring the continuation of ongoing vital missions being conducted by DOE on the Oak Ridge Reservation; and making clean land available for future use at all three sites, with a near-term focus on Re-industrialization of ETTP. (authors)
International Nuclear Information System (INIS)
Longworth, J.P.
1979-11-01
Consideration is given to the processes by which particles are removed from fluid systems. In particular, it is noted that in tank, as opposed to loop, systems the natural process of gravitational settling competes with engineered removal systems. Calculational methods are given for estimating the relative amounts of settling and removal to clean-up plant for well-mixed fluids, unmixed fluids with horizontal or vertical flow, and turbulent diffusion with incomplete mixing. The criteria for complete mixing are discussed. (author)
Di Egidio, Angelo; Contento, Alessandro; Vestroni, Fabrizio
2015-12-01
An open-cross section thin-walled beam model, already developed by the authors, has been conveniently simplified while maintaining the capacity of accounting for the significant nonlinear warping effects. For a technical range of geometrical and mechanical characteristics of the beam, the response is characterized by the torsional curvature prevailing over the flexural ones. A Galerkin discretization is performed by using a suitable expansion of displacements based on shape functions. The attention is focused on the dynamic response of the beam to a harmonic force, applied at the free end of the cantilever beam. The excitation is directed along the symmetry axis of the beam section. The stability of the one-component oscillations has been investigated using the analytical model, showing the importance of the internal resonances due to the nonlinear warping coupling terms. Comparison with the results provided by a computational finite element model has been performed. The good agreement among the results of the analytical and the computational models confirms the effectiveness of the simplified model of a nonlinear open-cross section thin-walled beam and overall the important role of the warping and of the torsional elongation in the study of the one-component dynamic oscillations and their stability.
Beam interaction of a pulsed, nonlinear in-vacuum injection magnet
International Nuclear Information System (INIS)
Rast, Helge
2013-01-01
Theme of this thesis is the study of the interaction of the injection magnet designed for BESSY II with the electron beam. The main topic of this thesis lies in the numerical and measurement-technical study of the loss factor, the wake potential, and the wake impedance of the nonlinear kicker magnet with the aim of an optimization of the magnet design, so that a stable operation of the kicker in the BESSY II storage ring is made possible. A further main topic of this thesis is a study on the matching of the injection scheme with a single kicker to the conditions of the DELTA storage ring, which is operated by the TU Dortmund.
Cichalewski, w
2010-01-01
The high power amplifiers transfer characteristics nonlinearities can have a negative influence on the overall system performance. This is also true for the TESLA superconducting cavities accelerating field parameters control systems. This Low Level Radio Frequency control systems uses microwave high power amplifiers (like 10 MW klystrons) as actuators in the mentioned feedback loops. The amplitude compression and phase deviations phenomena introduced to the control signals can reduce the feedback performance and cause electron beam energy instabilities. The transfer characteristics deviations in the Free Electron Laser in Hamburg experiment have been investigated. The outcome of this study together with the description of the developed linearization method based on the digital predistortion approach have been described in this paper. Additionally, the results from the linearization tool performance tests in the FLASH's RF systems have been placed.
Tran Hy, J
1998-01-01
This thesis describes some new studies of the effects of cubic nonlinearities arising from image-charge forces and octupole magnets on the transverse beam dynamics of proton synchrotrons and storage rings, and also a study of the damping of coherent oscillations using a feed-back damper. In the latter case, various corrective algorithms were modeled using linear one-turn maps. Kicks of fixed amplitude but appropriate sign were shown to provide linear damping and no coherent tune shift, though the rate predicted analytically was somewhat higher than that observed in simulations. This algorithm gave much faster damping (for equal power) than conventional proportional kicks, which damp exponentially. Two single-particle effects of the image-change force were investigated: distortion of the momentum dispersion function and amplitude dependence of the betatron tunes (resulting in tune spread). The former is calculated using transfer maps and the method of undetermined coefficients, the latter by solving the cubic ...
Fast spatial beam shaping by acousto-optic diffraction for 3D non-linear microscopy.
Akemann, Walther; Léger, Jean-François; Ventalon, Cathie; Mathieu, Benjamin; Dieudonné, Stéphane; Bourdieu, Laurent
2015-11-02
Acousto-optic deflection (AOD) devices offer unprecedented fast control of the entire spatial structure of light beams, most notably their phase. AOD light modulation of ultra-short laser pulses, however, is not straightforward to implement because of intrinsic chromatic dispersion and non-stationarity of acousto-optic diffraction. While schemes exist to compensate chromatic dispersion, non-stationarity remains an obstacle. In this work we demonstrate an efficient AOD light modulator for stable phase modulation using time-locked generation of frequency-modulated acoustic waves at the full repetition rate of a high power laser pulse amplifier of 80 kHz. We establish the non-local relationship between the optical phase and the generating acoustic frequency function and verify the system for temporal stability, phase accuracy and generation of non-linear two-dimensional phase functions.
Zock, J.P.; Rodríguez-Trigo, G.; Rodríguez-Rodríguez, E.; Souto-Alonso, A.; Espinosa, A.; Pozo-Rodríguez, F.; Gómez, F.P.; Fuster, C.; Castaño-Vinyals, G.; Antó, J.M.; Barberà, J.A.
2014-01-01
Fishermen who had participated in clean-up activities of the Prestige oil spill showed increased bronchial responsiveness and higher levels of respiratory biomarkers 2years later. We aimed to evaluate the persistence of these functional and biological respiratory health effects 6years after clean-up
Nonlinear Forced Vibration of a Viscoelastic Buckled Beam with 2 : 1 Internal Resonance
Directory of Open Access Journals (Sweden)
Liu-Yang Xiong
2014-01-01
Full Text Available Nonlinear dynamics of a viscoelastic buckled beam subjected to primary resonance in the presence of internal resonance is investigated for the first time. For appropriate choice of system parameters, the natural frequency of the second mode is approximately twice that of the first providing the condition for 2 : 1 internal resonance. The ordinary differential equations of the two mode shapes are established using the Galerkin method. The problem is replaced by two coupled second-order differential equations with quadratic and cubic nonlinearities. The multiple scales method is applied to derive the modulation-phase equations. Steady-state solutions of the system as well as their stability are examined. The frequency-amplitude curves exhibit the steady-state response in the directly excited and indirectly excited modes due to modal interaction. The double-jump, the saturation phenomenon, and the nonperiodic region phenomena are observed illustrating the influence of internal resonance. The validity range of the analytical approximations is assessed by comparing the analytical approximate results with a numerical solution by the Runge-Kutta method. The unstable regions in the internal resonance are explored via numerical simulations.
Nonlinear bound on unstable field energy in relativistic electron beams and plasmas
International Nuclear Information System (INIS)
Davidson, R.C.; Yoon, P.H.
1989-01-01
This paper makes use of Fowler's method [J. Math Phys. 4, 559 (1963)] to determine the nonlinear thermodynamic bound on field energy in unstable plasmas or electron beams in which the electrons are relativistic. Treating the electrons as the only active plasma component, the nonlinear Vlasov--Maxwell equations and the associated global conservation constraints are used to calculate the lowest upper bound on the field energy [ΔE-script/sub F/]/sub max/ that can evolve for the general initial electron distribution function f/sub b//sub / 0 equivalentf/sub b/(x,p,0). The results are applied to three choices of the initial distribution function f/sub b//sub / 0 . Two of the distribution functions have an inverted population in momentum p/sub perpendicular/ perpendicular to the magnetic field B 0 e/sub z/, and the third distribution function reduces to a bi-Maxwellian in the nonrelativistic limit. The lowest upper bound on the efficiency of radiation generation, eta/sub max/ = [ΔE-script/sub F/]/sub max//[V -1 ∫ d 3 x∫ d 3 p(γ-1)mc 2 f/sub b//sub / 0 ], is calculated numerically over a wide range of system parameters for varying degrees of initial anisotropy
Cappi, R; Martini, M; Métral, Elias; Métral, G; Steerenberg, R; Müller, A S
2003-01-01
The CERN Proton Synchrotron machine is built using combined function magnets. The control of the linear tune as well as the chromaticity in both planes is achieved by means of special coils added to the main magnets, namely two pole-face-windings and one figure-of-eight loop. As a result, the overall magnetic field configuration is rather complex not to mention the saturation effects induced at top-energy. For these reasons a linear model of the PS main magnet does not provide sufficient precision to model particle dynamics. On the other hand, a sophisticated optical model is the key element for the foreseen intensity upgrade and, in particular, for the novel extraction mode based on adiabatic capture of beam particles inside stable islands in transverse phase space. A solution was found by performing accurate measurement of the nonlinear tune as a function of both amplitude and momentum offset so to extract both linear and nonlinear properties of the lattice. In this paper the measurement results are present...
Zhang, Yan; Li, YuanYuan; Zhang, YunZhe
2018-03-01
We propose and experimentally demonstrate a controlled-not gate with light beams carrying orbital angular momentum (OAM) through a degenerate four-wave mixing process via a photonic band gap structure satisfying the phase-matching condition. By employing the different topological charges of a Laguerre-Gaussian beam as a qubit in this nonlinear process, the controlled-not gate with OAM can be realized. Moreover, we investigate the evolution of the controlled-not gate, which can be modulated by the frequency and the power of the incident beam, i.e., under electromagnetically induced transparency conditions. The study results are useful for applications in quantum communication and information storage.
Numerical simulation of nonlinear beam-plasma interaction for the application to solar radio burst
International Nuclear Information System (INIS)
Takakura, T.
1981-01-01
By the use of semi-analytical method the numerical simulations for the nonlinear scattering of axially symmetric plasma waves into plasma waves and radio waves have been made. The initial electron beam has a finite length and one-dimensional velocity distribution of power law. Induced back-scattering of plasma waves by thermal ions is strong even for a solar electron stream of rather low flux, say 2x10 11 cm -2 above 5 keV at fsub(p) of 40 MHz, which is enough to emit the observed type III bursts as the second harmonic. The ratio between the energy densities of plasma waves and thermal electrons (nkT) is of the order of 10 -6 , which may be a few orders lower than the threshold value for a caviton collapse of the plasma waves to occur. The second harmonic radio emission as attributed to the coalescence of two plasma waves, i.e. one excited by electron beam and one back-scattered by ions, is several orders higher than the fundamental radio emission caused by the scattering of plasma waves by thermal ions. (Auth.)
International Nuclear Information System (INIS)
Cornacchia, M.; Evans, L.
1985-06-01
A nonlinear lens may be used to study the effect of high-order multipolar field imperfections on a stored proton beam. Such a nonlinear lens is particulary suitable to simulate field imperfections of the types encountered in coil dominated superconducting magnets. We have studied experimentally at the SPS the effect of high order (5th and 8th) single isolated resonances driven by the nonlinear lens. The width of these resonances is of the order one expects to be caused by field errors in superconducting magnets of the SSC type. The experiment shows that, in absence of tune modulation, these resonances are harmless. Slow crossings of the resonance, on the other hand, have destructive effects on the beam, much more so than fast crossings caused by synchrotron oscillations. In the design of future storage rings, sources of low-frequency tune modulation should be avoided as a way to reduce the harmful effects of high order multipolar field imperfection
Karaton, Muhammet
2014-01-01
A beam-column element based on the Euler-Bernoulli beam theory is researched for nonlinear dynamic analysis of reinforced concrete (RC) structural element. Stiffness matrix of this element is obtained by using rigidity method. A solution technique that included nonlinear dynamic substructure procedure is developed for dynamic analyses of RC frames. A predicted-corrected form of the Bossak-α method is applied for dynamic integration scheme. A comparison of experimental data of a RC column element with numerical results, obtained from proposed solution technique, is studied for verification the numerical solutions. Furthermore, nonlinear cyclic analysis results of a portal reinforced concrete frame are achieved for comparing the proposed solution technique with Fibre element, based on flexibility method. However, seismic damage analyses of an 8-story RC frame structure with soft-story are investigated for cases of lumped/distributed mass and load. Damage region, propagation, and intensities according to both approaches are researched.
International Nuclear Information System (INIS)
Li Qing; Wang Tianshu; Ma Xingrui
2009-01-01
Flexible-body modeling with geometric nonlinearities remains a hot topic of research by applications in multibody system dynamics undergoing large overall motions. However, the geometric nonlinear effects on the impact dynamics of flexible multibody systems have attracted significantly less attention. In this paper, a point-surface impact problem between a rigid ball and a pivoted flexible beam is investigated. The Hertzian contact law is used to describe the impact process, and the dynamic equations are formulated in the floating frame of reference using the assumed mode method. The two important geometric nonlinear effects of the flexible beam are taken into account, i.e., the longitudinal foreshortening effect due to the transverse deformation, and the stress stiffness effect due to the axial force. The simulation results show that good consistency can be obtained with the nonlinear finite element program ABAQUS/Explicit if proper geometric nonlinearities are included in the floating frame formulation. Specifically, only the foreshortening effect should be considered in a pure transverse impact for efficiency, while the stress stiffness effect should be further considered in an oblique case with much more computational effort. It also implies that the geometric nonlinear effects should be considered properly in the impact dynamic analysis of more general flexible multibody systems
International Nuclear Information System (INIS)
Shokair, I.R.
1991-01-01
Phase mixing of transverse oscillations changes the nature of the ion hose instability from an absolute to a convective instability. The stronger the phase mixing, the faster an electron beam reaches equilibrium with the guiding ion channel. This is important for long distance propagation of relativistic electron beams where it is desired that transverse oscillations phase mix within a few betatron wavelengths of injection and subsequently an equilibrium is reached with no further beam emittance growth. In the linear regime phase mixing is well understood and results in asymptotic decay of transverse oscillations as 1/Z 2 for a Gaussian beam and channel system, Z being the axial distance measured in betatron wavelengths. In the nonlinear regime (which is likely mode of propagation for long pulse beams) results of the spread mass model indicate that phase mixing is considerably weaker than in the regime. In this paper we consider this problem of phase mixing in the nonlinear regime. Results of the spread mass model will be shown along with a simple analysis of phase mixing for multiple oscillator models. Particle simulations also indicate that phase mixing is weaker in nonlinear regime than in the linear regime. These results will also be shown. 3 refs., 4 figs
Directory of Open Access Journals (Sweden)
Iman Eshraghi
2016-09-01
Full Text Available Imperfection sensitivity of large amplitude vibration of curved single-walled carbon nanotubes (SWCNTs is considered in this study. The SWCNT is modeled as a Timoshenko nano-beam and its curved shape is included as an initial geometric imperfection term in the displacement field. Geometric nonlinearities of von Kármán type and nonlocal elasticity theory of Eringen are employed to derive governing equations of motion. Spatial discretization of governing equations and associated boundary conditions is performed using differential quadrature (DQ method and the corresponding nonlinear eigenvalue problem is iteratively solved. Effects of amplitude and location of the geometric imperfection, and the nonlocal small-scale parameter on the nonlinear frequency for various boundary conditions are investigated. The results show that the geometric imperfection and non-locality play a significant role in the nonlinear vibration characteristics of curved SWCNTs.
International Nuclear Information System (INIS)
Santucci, C.
2008-01-01
Among the different activities of the CEA research centre in Cadarache, located in the south of France, one of the most important involves cleaning, cleansing dismantling, decommissioning, and recovery of legacy wastes. This presentation will give an overview of the waste retrieval project from the historical interim storage facility called INB 56. The project is divided into three different sub-projects: the historical unpacked waste retrieval, the historical canister retrieval and the draining and clean-up of the spent fuel pools. All the described operations are conducted in accordance with the ALARA principle and the optimization of the waste categorization. The overall project, including the complete clean-up of the facility and its de-licensing, is due to end by 2020. The aim of this document is to outline the general ongoing historical waste retrieval operations and future projects on the INB 56 at the Cadarache research centre. In the final analysis, it can be seen that most of the waste is to be sent to the new CEDRA facility. Nevertheless one major goal of this project is to optimize the waste categorization and therefore to send the canisters to the ANDRA LLW site whenever possible. Two means will allow us to reach this goal: - The sorting out of un-packed waste in order to constitute a LLW canister - A wide range of measurements (gamma spectrometry, neutron measurement, tomography) in order to assess the exact nature of the contents in the historical canisters. Taking waste treatment and conditioning into account well in advance is a factor of prime importance that must be managed early in the elaboration of the decommissioning scenario. Precise knowledge of the physical and radiological inventories is of the utmost importance in defining the best waste pathway. Overall operations on the facility are due to end by 2020 including complete clean-up of the facility and its de-licensing
Non-linear beam dynamics tests in the LHC: LHC dynamic aperture MD on Beam 2 (24th of June 2012)
Maclean, E H; Persson, T H B; Redaelli, S; Schmidt, F; Tomas, R; Uythoven, J
2013-01-01
This MD note summarizes measurements performed on LHC Beam 2 during the non-linear machine development (MD) of 24 June 2012. The aim of the measurement was to observe the dynamic aperture of LHC Beam 2, and obtain turn-by-turn (TbT) betatron oscillation data, enabling the study of amplitude detuning and resonance driving terms (RDTs). The regular injections required by the MD also represented an opportunity to test a new coupling feedback routine based on the analysis of injection oscillation data. Initial measurements were performed on the nominal state of the LHC at injection. On completion of this study the Landau octupoles were turned off and corrections for higher-order chromaticities were implemented to reduce the non-linearity of the machine as far as possible. A second set of measurements were then performed. All studies were performed using the LHC aperture kicker (MKA).
Yankovskii, A. P.
2017-09-01
The creep of homogenous and hybrid composite beams of an irregular laminar fibrous structure is investigated. The beams consist of thin walls and flanges (load-carrying layers). The walls may be reinforced longitudinally or crosswise in the plane, and the load-carrying layers are reinforced in the longitudinal direction. The mechanical behavior of phase materials is described by the Rabotnov nonlinear hereditary theory of creep taking into account their possible different resistance to tension and compression. On the basis of hypotheses of the Timoshenko theory, with using the method of time steps, a problem is formulated for the inelastic bending deformation of such beams with account of the weakened resistance of their walls to the transverse shear. It is shown that, at discrete instants of time, the mechanical behavior of such structures can formally be described by the governing relations for composite beams made of nonlinear elastic anisotropic materials with a known initial stress state. The method of successive iterations, similar to the method of variable parameters of elasticity, is used to linearize the boundary-value problem at each instant of time. The bending deformation is investigated for homogeneous and reinforced cantilever and simply supported beams in creep under the action of a uniformly distributed transverse load. The cross sections of the beams considered are I-shaped. It is found that the use of the classical theory for such beams leads to the prediction of indefensibly underestimated flexibility, especially in long-term loading. It is shown that, in beams with reinforced load-carrying layers, the creep mainly develops due to the shear strains of walls. It is found that, in short- and long-term loadings of composite beams, the reinforcement structures rational by the criterion of minimum flexibility are different.
Sahmani, S.; Aghdam, M. M.
2018-03-01
A wide range of biological applications such as drug delivery, biosensors and hemodialysis can be provided by nanoporous biomaterials due to their uniform pore size as well as considerable pore density. In the current study, the size dependency in the nonlinear primary resonance of micro/nano-beams made of nanoporous biomaterials is anticipated. To accomplish this end, a refined truncated cube is introduced to model the lattice structure of nanoporous biomaterial. Accordingly, analytical expressions for the mechanical properties of material are derived as functions of pore size. After that, based upon a nonlocal strain gradient beam model, the size-dependent nonlinear Duffing type equation of motion is constructed. The Galerkin technique together with the multiple time-scales method is employed to obtain the nonlocal strain gradient frequency-response and amplitude-response related to the nonlinear primary resonance of a micro/nano-beam made of the nanoporous biomaterial with different pore sizes. It is indicated that the nonlocality causes to decrease the response amplitudes associated with the both bifurcation points of the jump phenomenon, while the strain gradient size dependency causes to increase them. Also, it is found that increasing the pore size leads to enhance the nonlinearity, so the maximum deflection of response occurs at higher excitation frequency.
Directory of Open Access Journals (Sweden)
Adailton S. Borges
Full Text Available Abstract A broad class of engineering systems can be satisfactory modeled under the assumptions of small deformations and linear material properties. However, many mechanical systems used in modern applications, like structural elements typical of aerospace and petroleum industries, have been characterized by increased slenderness and high static and dynamic loads. In such situations, it becomes indispensable to consider the nonlinear geometric effects and/or material nonlinear behavior. At the same time, in many cases involving dynamic loads, there comes the need for attenuation of vibration levels. In this context, this paper describes the development and validation of numerical models of viscoelastic slender beam-like structures undergoing large displacements. The numerical approach is based on the combination of the nonlinear Cosserat beam theory and a viscoelastic model based on Fractional Derivatives. Such combination enables to derive nonlinear equations of motion that, upon finite element discretization, can be used for predicting the dynamic behavior of the structure in the time domain, accounting for geometric nonlinearity and viscoelastic damping. The modeling methodology is illustrated and validated by numerical simulations, the results of which are compared to others available in the literature.
Directory of Open Access Journals (Sweden)
Teeraphot Supaviriyakit
2017-11-01
Full Text Available This paper presents a nonlinear finite element analysis of non-seismically detailed RC beam column connections under reversed cyclic load. The test of half-scale nonductile reinforced concrete beam-column joints was conducted. The tested specimens represented those of the actual mid-rise reinforced concrete frame buildings designed according to the non-seismic provisions of the ACI building code. The test results show that specimens representing small and medium column tributary area failed in brittle joint shear while specimen representing large column tributary area failed by ductile flexure though no ductile reinforcement details were provided. The nonlinear finite element analysis was applied to simulate the behavior of the specimens. The finite element analysis employs the smeared crack approach for modeling beam, column and joint, and employs the discrete crack approach for modeling the interface between beam and joint face. The nonlinear constitutive models of reinforced concrete elements consist of coupled tension-compression model to model normal force orthogonal and parallel to the crack and shear transfer model to capture the shear sliding mechanism. The FEM shows good comparison with test results in terms of load-displacement relations, hysteretic loops, cracking process and the failure mode of the tested specimens. The finite element analysis clarifies that the joint shear failure was caused by the collapse of principal diagonal concrete strut.
Cho, Youngsoo; Cattrall, Robert W; Kolev, Spas D
2018-01-05
Thiocyanate is present in gold mine tailings waters in concentrations up to 1000mgL -1 and this has a serious environmental impact by not allowing water reuse in the flotation of gold ore. This significantly increases the consumption of fresh water and the amount of wastewater discharged in tailings dams. At the same time thiocyanate in tailings waters often leads to groundwater contamination. A novel continuous membrane-based method for the complete clean-up of thiocyanate in concentrations as high as 1000mgL -1 from its aqueous solutions has been developed. It employs a flat sheet polymer inclusion membrane (PIM) of composition 70wt% PVC, 20wt% Aliquat 336 and 10wt% 1-tetradecanol which separates counter-current streams of a feed thiocyanate solution and a 1M NaNO 3 receiving solution. The PIM-based system has been operated continuously for 45days with 99% separation efficiency. The volume of the receiving solution has been drastically reduced by recirculating it and continuously removing thiocyanate by precipitating it with in-situ generated Cu(I). The newly developed PIM-based thiocyanate clean-up method is environmentally friendly in terms of reagent use and inexpensive with respect to both equipment and running costs. Copyright © 2017 Elsevier B.V. All rights reserved.
International Nuclear Information System (INIS)
Kalnina, I.; Meirovics, I.; Garbuseva, N.; Bruvere, R.; Heisele, O.; Zvagule, T.; Volrate, A.; Feldmane, G.
2001-01-01
A fluorescent probe - aminoderivative of benzanthrone, AMB (developed at the Riga Technical University, Riga, Latvia) - has been previously shown to localise within the phospholipid bilayer of the cell membrane, and shown to affect the structural and functional properties of peripheral blood mononuclear cells (PBMC). The probe ABM was used to characterise the PBMC membranes of 97 Chernobyl clean-up workers from Latvia. The study was conducted in the years 1997-1998. After addition of the probe to PBMC, fluorescence intensity of ABM (F) was measured, the depolarisation value P was calculated, and emission spectra were recorded. Screening of all individuals showed 5 different patterns of fluorescence spectra. Four of the patterns had never been previously observed in healthy individuals or patients with tuberculosis, multiple sclerosis, oncologic patients, etc., examined by us. The spectral patterns of ABM suspensions were associated with ability of leukocytes to produce interferons, with the levels of immunoglobulins A, G, and M, the concentration of lead in peripheral blood, and with several neurologic diseases. The use of ABM allowed to show phenotypic differences in PBMC between Chernobyl clean-up workers and individuals who had never had professional contact with radioactivity. (author)
Ye, Cui; Zhao, Zhihe; Zhao, Qing; Du, Xi; Ye, Jun; Wei, Xing
2013-11-01
The aim of this study was to compare whether there was any difference in the enamel discoloration after staining when three orthodontic adhesives and four enamel clean-up methods were tested. Three types of orthodontic adhesives were used: chemically cured resin, light-cured resin and resin-modified glass-ionomer cement. A total of 120 human extracted premolars were included. 10 teeth of each orthodontic adhesive were randomly cleaned-up with one of four different procedures and stained in coffee for seven days: (1) carbide bur (TC); (2) carbide bur; Sof-Lex polishers (TC+SL); (3) carbide bur and one gloss polishers (TC+OG); and (4) carbide bur and PoGo polishers (TC+PG). Color measurements were made with Crystaleye dental spectrophotometer at baseline and after storage in a coffee solution one week. Two-way ANOVA and Bonferroni tests were used for statistical analyses (P0.05). The resin-modified glass-ionomer cement groups showed the lowest color differences and chemically cured resin groups showed the highest ΔE* values among all the orthodontic adhesives (P<0.05). The color change of enamel surface was affected by the type of adhesive materials and cleanup procedures. Copyright © 2013 Elsevier Ltd. All rights reserved.
Nonlinear fracture mechanics investigation on the ductility of reinforced concrete beams
Directory of Open Access Journals (Sweden)
A. Carpinteri
Full Text Available In the present paper, a numerical algorithm based on the finite element method is proposed for the prediction of the mechanical response of reinforced concrete (RC beams under bending loading. The main novelty of such an approach is the introduction of the Overlapping Crack Model, based on nonlinear fracture mechanics concepts, to describe concrete crushing. According to this model, the concrete dam- age in compression is represented by means of a fictitious interpenetration. The larger is the interpenetration, the lower are the transferred forces across the damaged zone. The well-known Cohesive Crack Model in tension and an elastic-perfectly plastic stress versus crack opening displacement relationship describing the steel reinforcement behavior are also integrated into the numerical algorithm. The application of the proposed Cohesive-Overlapping Crack Model to the assessment of the minimum reinforcement amount neces- sary to prevent unstable tensile crack propagation and to the evaluation of the rotational capacity of plastic hinges, permits to predict the size-scale effects evidenced by several experimental programs available in the literature. According to the obtained numerical results, new practical design formulae and diagrams are proposed for the improvement of the current code provisions which usually disregard the size effects.
Statistical study of the non-linear propagation of a partially coherent laser beam
International Nuclear Information System (INIS)
Ayanides, J.P.
2001-01-01
This research thesis is related to the LMJ project (Laser MegaJoule) and thus to the study and development of thermonuclear fusion. It reports the study of the propagation of a partially-coherent laser beam by using a statistical modelling in order to obtain mean values for the field, and thus bypassing a complex and costly calculation of deterministic quantities. Random fluctuations of the propagated field are supposed to comply with a Gaussian statistics; the laser central wavelength is supposed to be small with respect with fluctuation magnitude; a scale factor is introduced to clearly distinguish the scale of the random and fast variations of the field fluctuations, and the scale of the slow deterministic variations of the field envelopes. The author reports the study of propagation through a purely linear media and through a non-dispersive media, and then through slow non-dispersive and non-linear media (in which the reaction time is large with respect to grain correlation duration, but small with respect to the variation scale of the field macroscopic envelope), and thirdly through an instantaneous dispersive and non linear media (which instantaneously reacts to the field) [fr
International Nuclear Information System (INIS)
2010-01-01
As any nuclear base installation evolves during its exploitation, some premises or buildings may change of use or be destroyed. In the first case, a complete cleaning up might be necessary to get rid of radioactive products. In order to deal with this issue, after a brief recall of the regulatory context and references, and a recall of the general doctrine of waste management in nuclear base installations in France, this guide project presents the principles for a complete cleaning up of structures belonging to an area containing nuclear wastes. It describes the modalities of definition of three different and successive defence lines. It defines the requirements in performing cleaning-up operations, the requirements in terms of quality insurance, and the different administrative procedures (before, during and after cleaning-up works). Some particular cases are addressed
Directory of Open Access Journals (Sweden)
Hamid M. Sedighi
Full Text Available This paper investigates the dynamic pull-in instability of vibrating micro-beams undergoing large deflection under electrosatically actuation. The governing equation of motion is derived based on the modified couple stress theory. Homotopy Perturbation Method is employed to produce the high accuracy approximate solution as well as the second-order frequency- amplitude relationship. The nonlinear governing equation of micro beam vibrations predeformed by an electric field includes both even and odd nonlinearities. The influences of basic non-dimensional parameters on the pull-in instability as well as the natural frequency are studied. It is demonstrated that two terms in series expansions are sufficient to produce high accuracy solution of the micro-structure. The accuracy of proposed asymptotic approach is validated via numerical results. The phase portrait of the system exhibits periodic and homoclinic orbits.
Directory of Open Access Journals (Sweden)
Piotr Koziol
2012-01-01
Full Text Available This paper presents a new semi-analytical solution for the Timoshenko beam subjected to a moving load in case of a nonlinear medium underneath. The finite series of distributed moving loads harmonically varying in time is considered as a representation of a moving train. The solution for vibrations is obtained by using the Adomian's decomposition combined with the Fourier transform and a wavelet-based procedure for its computation. The adapted approximating method uses wavelet filters of Coiflet type that appeared a very effective tool for vibration analysis in a few earlier papers. The developed approach provides solutions for both transverse displacement and angular rotation of the beam, which allows parametric analysis of the investigated dynamic system to be conducted in an efficient manner. The aim of this article is to present an effective method of approximation for the analysis of complex dynamic nonlinear models related to the moving load problems.
Energy Technology Data Exchange (ETDEWEB)
Heinecker, C.; Pickel, H.-J.; Duffek, J. [HPC Harress Pickel Consult GmbH, Fuldatal (Germany)
1995-12-31
At the request of the former plant operator, a manufactured gas plant site in Tuttlingen, Germany, was investigated from 1988 through 1992 for subsurface soil contamination resulting from former activities. In 1991, the contents of the former tar pits and parts of the adjacent soil contaminations were removed in the course of clean-up activities by means of excavation and disposed at a special waste site. Following an initial risk assessment, a remedial investigation was carried out in order to further delineate the contaminated areas as well as to create a reliable database for a feasibility study of remedial alternatives. The feasibility study followed applicable Baden-Wurttemberg state guidelines, including the following elements: Determination of the clean-up goals for soils; pre-selection of the clean-up procedure; cost estimate; cost-effectiveness study; Non-monetary evaluation; and total evaluation/clean-up proposal. The following general alternatives were available for the definition of clean-up goals: background values (`H-values`); general guidelines values (`SZ-values`); and clean-up goals based on contaminant fate and transport as well as site use (`SZA-values`).
International Nuclear Information System (INIS)
Ghayesh, Mergen H.; Amabili, Marco; Farokhi, Hamed
2013-01-01
In the present study, the coupled nonlinear dynamics of an axially moving viscoelastic beam with time-dependent axial speed is investigated employing a numerical technique. The equations of motion for both the transverse and longitudinal motions are obtained using Newton’s second law of motion and the constitutive relations. A two-parameter rheological model of the Kelvin–Voigt energy dissipation mechanism is employed in the modelling of the viscoelastic beam material, in which the material time derivative is used in the viscoelastic constitutive relation. The Galerkin method is then applied to the coupled nonlinear equations, which are in the form of partial differential equations, resulting in a set of nonlinear ordinary differential equations (ODEs) with time-dependent coefficients due to the axial acceleration. A change of variables is then introduced to this set of ODEs to transform them into a set of first-order ordinary differential equations. A variable step-size modified Rosenbrock method is used to conduct direct time integration upon this new set of first-order nonlinear ODEs. The mean axial speed and the amplitude of the speed variations, which are taken as bifurcation parameters, are varied, resulting in the bifurcation diagrams of Poincaré maps of the system. The dynamical characteristics of the system are examined more precisely via plotting time histories, phase-plane portraits, Poincaré sections, and fast Fourier transforms (FFTs)
Nonlinear Phenomena in the Single-Mode Dynamics in an AFM Cantilever Beam
Ruzziconi, Laura
2016-12-05
This study deals with the nonlinear dynamics arising in an atomic force microscope cantilever beam. After analyzing the static behavior, a single degree of freedom Galerkin reduced order model is introduced, which describes the overall scenario of the structure response in a neighborhood of the primary resonance. Extensive numerical simulations are performed when both the forcing amplitude and frequency are varied, ranging from low up to elevated excitations. The coexistence of competing attractors with different characteristics is analyzed. Both the non-resonant and the resonant behavior are observed, as well as ranges of inevitable escape. Versatility of behavior is highlighted, which may be attractive in applications. Special attention is devoted to the effects of the tip-sample separation distance, since this aspect is of fundamental importance to understand the operation of an AFM. We explore the metamorphoses of the multistability region when the tip-sample separation distance is varied. To have a complete description of the AFM response, comprehensive behavior charts are introduced to detect the theoretical boundaries of appearance and disappearance of the main attractors. Also, extensive numerical simulations investigate the AFM response when both the forcing amplitude and the tip-sample separation distance are considered as control parameters. The main features are analyzed in detail and the obtained results are interpreted in terms of oscillations of the cantilever-tip ensemble. However, we note that all the aforementioned results represent the limit when disturbances are absent, which never occurs in practice. Here comes the importance of overcoming local investigations and exploring dynamics from a global perspective, by introducing dynamical integrity concepts. To extend the AFM results to the practical case where disturbances exist, we develop a dynamical integrity analysis. After performing a systematic basin of attraction analysis, integrity
Directory of Open Access Journals (Sweden)
Carlos A. Borzone
2009-12-01
Full Text Available A geomorphological and faunistic seasonal study of six estuarine beaches on Paranaguá Bay, Brazil, was abruptly interrupted when the Chilean ship "Vicuña" exploded and sank, spilling 291 tons of bunker fuel oil. The beaches sampled twice before the accident were affected by the oil spill deposition and the posterior clean-up activities. Neither drastic reduction in abundances nor occurrences of oil-covered individuals were registered. Significant variation in both amount of debris and talitrid amphipod densities was directly related to beach clean-up activities. A short (1-3 month manual clean-up of polluted wrack resulted in an increase in talitrid abundances, with the local distribution expansion of one species, Platorchestia monodi, from three to six of the beaches sampled. The active migration and concentration of organisms at sites without wrack during cleaning activities and a massive and continuous recovery of new debris, characteristic of estuarine beaches, may contribute to the findings.Um estudo sazonal da geomorfologia e fauna de seis praias estuarinas na baia de Paranaguá, Brasil, foi interrompido bruscamente pela explosão e posterior afundamento do navio chileno Vicuña, que derramou 291 toneladas de óleo bunker. As praias que foram afetadas pela deposição de óleo e pelas posteriores atividades de limpeza, tinham sido amostradas duas vezes antes do acidente. Nas coletas posteriores ao acidente não foram registradas nem reduções drásticas das abundâncias nem indivíduos impregnados por óleo. As significativas variações tanto da quantidade de detrito quanto nas densidades de anfipodes talitrídeos foram relacionadas às atividades de limpeza. Uma limpeza manual e de curta duração (1 a 3 meses resultou num aumento das abundâncias dos talitrídeos, juntamente com o aumento da distribuição de uma das espécies, Platorchestia monodi, que de três passou a ser encontrada em seis praias amostradas.Os fatores que
Energy Technology Data Exchange (ETDEWEB)
Fenili, André; Lopes Rebello da Fonseca Brasil, Reyolando Manoel [Universidade Federal do ABC (UFABC), Centro de Engenharia, Modelagem e Ciências Sociais Aplicadas (CECS) / Aerospace Engineering Santo André, São Paulo (Brazil); Balthazar, José M., E-mail: jmbaltha@gmail.com [Universidade Federal do ABC (UFABC), Centro de Engenharia, Modelagem e Ciências Sociais Aplicadas (CECS) / Aerospace Engineering Santo André, São Paulo, Brazil and Universidade Estadual Paulista, Faculdade de Engenharia Mec and #x00E (Brazil); Francisco, Cayo Prado Fernandes [Universidade Federal do ABC (UFABC), Centro de Engenharia, Modelagem e Ciências Sociais Aplicadas (CECS) / Aerospace Engineering Santo André, São Paulo, Brazil and Instituto de Aeronáutica e Espaço, Departamento de (Brazil)
2014-12-10
We derive nonlinear governing equations without assuming that the beam is inextensible. The derivation couples the equations that govern a weak electric motor, which is used to rotate the base of the beam, to those that govern the motion of the beam. The system is considered non-ideal in the sense that the response of the motor to an applied voltage and the motion of the beam must be obtained interactively. The moment that the motor exerts on the base of the beam cannot be determined without solving for the motion of the beam.
International Nuclear Information System (INIS)
Fenili, André; Lopes Rebello da Fonseca Brasil, Reyolando Manoel; Balthazar, José M.; Francisco, Cayo Prado Fernandes
2014-01-01
We derive nonlinear governing equations without assuming that the beam is inextensible. The derivation couples the equations that govern a weak electric motor, which is used to rotate the base of the beam, to those that govern the motion of the beam. The system is considered non-ideal in the sense that the response of the motor to an applied voltage and the motion of the beam must be obtained interactively. The moment that the motor exerts on the base of the beam cannot be determined without solving for the motion of the beam
International Nuclear Information System (INIS)
Plaisier, L.
1990-01-01
The necessity to optimize condensate clean-up by means of powder resin precoat filtration has gained more and more importance. Not only the cost of powder resins themselves is important in this regard, but even more so the disposal of used resins and replaced filter elements. The factors influencing direct filtration efficiency, resin consumption, and service life of filter elements (powder resin quality; way of preparing the water - resin mixture; precoating method; filter design and piping; type and quality of filter elements, and filtration speed) are outlined. A method designed to reduce filtration speed as much as possible, i.e. to enlarge the filter surface while maintaining its volume and avoiding adverse effects, is described in detail and substantiated by data obtained from pilot tests. (orig./BBR) [de
Kania-Korwel, Izabela; Zhao, Hongxia; Norstrom, Karin; Li, Xueshu; Hornbuckle, Keri C.; Lehmler, Hans-Joachim
2008-01-01
A pressurized liquid extraction-based method for the simultaneous extraction and in situ clean-up of polychlorinated biphenyls (PCBs), hydroxylated (OH)-PCBs and methylsulfonyl (MeSO2)-PCBs from small (< 0.5 gram) tissue samples was developed and validated. Extraction of a laboratory reference material with hexane:dichloromethane:methanol (48:43:9, v/v) and Florisil as fat retainer allowed an efficient recovery of PCBs (78–112%; RSD: 13–37%), OH-PCBs (46±2%; RSD: 4%) and MeSO2-PCBs (89±21%; RSD: 24%). Comparable results were obtained with an established analysis method for PCBs, OH-PCBs and MeSO2-PCBs. PMID:19019378
BOERTJENS, G. J.; VAN HORSSEN, W. T.
2000-08-01
In this paper an initial-boundary value problem for the vertical displacement of a weakly non-linear elastic beam with an harmonic excitation in the horizontal direction at the ends of the beam is studied. The initial-boundary value problem can be regarded as a simple model describing oscillations of flexible structures like suspension bridges or iced overhead transmission lines. Using a two-time-scales perturbation method an approximation of the solution of the initial-boundary value problem is constructed. Interactions between different oscillation modes of the beam are studied. It is shown that for certain external excitations, depending on the phase of an oscillation mode, the amplitude of specific oscillation modes changes.
Cantú, Ricardo; Shoemaker, Jody A; Kelty, Catherine A; Wymer, Larry J; Behymer, Thomas D; Dufour, Alfred P; Magnuson, Matthew L
2017-08-22
The use of cyanuric acid as a biomarker for ingestion of swimming pool water may lead to quantitative knowledge of the volume of water ingested during swimming, contributing to a better understanding of disease resulting from ingestion of environmental contaminants. When swimming pool water containing chlorinated cyanurates is inadvertently ingested, cyanuric acid is excreted quantitatively within 24 h as a urinary biomarker of ingestion. Because the volume of water ingested can be quantitatively estimated by calculation from the concentration of cyanuric acid in 24 h urine samples, a procedure for preservation, cleanup, and analysis of cyanuric acid was developed to meet the logistical demands of large scale studies. From a practical stand point, urine collected from swimmers cannot be analyzed immediately, given requirements of sample collection, shipping, handling, etc. Thus, to maintain quality control to allow confidence in the results, it is necessary to preserve the samples in a manner that ensures as quantitative analysis as possible. The preservation and clean-up of cyanuric acid in urine is complicated because typical approaches often are incompatible with the keto-enol tautomerization of cyanuric acid, interfering with cyanuric acid sample preparation, chromatography, and detection. Therefore, this paper presents a novel integration of sample preservation, clean-up, chromatography, and detection to determine cyanuric acid in 24 h urine samples. Fortification of urine with cyanuric acid (0.3-3.0 mg/L) demonstrated accuracy (86-93% recovery) and high reproducibility (RSD urine suggested sufficient cyanuric acid stability for sample collection procedures, while longer holding times suggested instability of the unpreserved urine. Preserved urine exhibited a loss of around 0.5% after 22 days at refrigerated storage conditions of 4 °C. Published by Elsevier B.V.
Separation techniques for the clean-up of radioactive mixed waste for ICP-AES/ICP-MS analysis
International Nuclear Information System (INIS)
Swafford, A.M.; Keller, J.M.
1993-01-01
Two separation techniques were investigated for the clean-up of typical radioactive mixed waste samples requiring elemental analysis by Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) or Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). These measurements frequently involve regulatory or compliance criteria which include the determination of elements on the EPA Target Analyte List (TAL). These samples usually consist of both an aqueous phase and a solid phase which is mostly an inorganic sludge. Frequently, samples taken from the waste tanks contain high levels of uranium and thorium which can cause spectral interferences in ICP-AES or ICP-MS analysis. The removal of these interferences is necessary to determine the presence of the EPA TAL elements in the sample. Two clean-up methods were studied on simulated aqueous waste samples containing the EPA TAL elements. The first method studied was a classical procedure based upon liquid-liquid extraction using tri-n- octylphosphine oxide (TOPO) dissolved in cyclohexane. The second method investigated was based on more recently developed techniques using extraction chromatography; specifically the use of a commercially available Eichrom TRU·Spec trademark column. Literature on these two methods indicates the efficient removal of uranium and thorium from properly prepared samples and provides considerable qualitative information on the extraction behavior of many other elements. However, there is a lack of quantitative data on the extraction behavior of elements on the EPA Target Analyte List. Experimental studies on these two methods consisted of determining whether any of the analytes were extracted by these methods and the recoveries obtained. Both methods produced similar results; the EPA target analytes were only slightly or not extracted. Advantages and disadvantages of each method were evaluated and found to be comparable
Sahmani, S.; Aghdam, M. M.
2017-12-01
Morphology and pore size plays an essential role in the mechanical properties as well as the associated biological capability of a porous structure made of biomaterials. The objective of the current study is to predict the Young's modulus and Poisson's ratio of nanoporous biomaterials including refined truncated cube cells based on a hyperbolic shear deformable beam model. Analytical relationships for the mechanical properties of nanoporous biomaterials are given as a function of the refined cell's dimensions. After that, the size dependency in the nonlinear bending behavior of micro/nano-beams made of such nanoporous biomaterials is analyzed using the nonlocal strain gradient elasticity theory. It is assumed that the micro/nano-beam has one movable end under axial compression in conjunction with a uniform distributed lateral load. The Galerkin method together with an improved perturbation technique is employed to propose explicit analytical expression for nonlocal strain gradient load-deflection curves of the micro/nano-beams made of nanoporous biomaterials subjected to uniform transverse distributed load. It is found that through increment of the pore size, the micro/nano-beam will undergo much more deflection corresponding to a specific distributed load due to the reduction in the stiffness of nanoporous biomaterial. This pattern is more prominent for lower value of applied axial compressive load at the free end of micro/nano-beam.
International Nuclear Information System (INIS)
Wang, Lin; Liu, Xiongwei; Renevier, Nathalie; Stables, Matthew; Hall, George M.
2014-01-01
Due to the increasing size and flexibility of large wind turbine blades, accurate and reliable aeroelastic modelling is playing an important role for the design of large wind turbines. Most existing aeroelastic models are linear models based on assumption of small blade deflections. This assumption is not valid anymore for very flexible blade design because such blades often experience large deflections. In this paper, a novel nonlinear aeroelastic model for large wind turbine blades has been developed by combining BEM (blade element momentum) theory and mixed-form formulation of GEBT (geometrically exact beam theory). The nonlinear aeroelastic model takes account of large blade deflections and thus greatly improves the accuracy of aeroelastic analysis of wind turbine blades. The nonlinear aeroelastic model is implemented in COMSOL Multiphysics and validated with a series of benchmark calculation tests. The results show that good agreement is achieved when compared with experimental data, and its capability of handling large deflections is demonstrated. Finally the nonlinear aeroelastic model is applied to aeroelastic modelling of the parked WindPACT 1.5 MW baseline wind turbine, and reduced flapwise deflection from the nonlinear aeroelastic model is observed compared to the linear aeroelastic code FAST (Fatigue, Aerodynamics, Structures, and Turbulence). - Highlights: • A novel nonlinear aeroelastic model for wind turbine blades is developed. • The model takes account of large blade deflections and geometric nonlinearities. • The model is reliable and efficient for aeroelastic modelling of wind turbine blades. • The accuracy of the model is verified by a series of benchmark calculation tests. • The model provides more realistic aeroelastic modelling than FAST (Fatigue, Aerodynamics, Structures, and Turbulence)
Natural Frequencies and Mode Shapes of a Nonlinear, Uniform Cantilevered Beam
National Research Council Canada - National Science Library
Marquez-Chisolm, Daniel J
2006-01-01
.... These experiments used a homogeneous 7075 aluminum beam and have been referenced as a baseline for the past thirty years to validate computer models and theories in an effort to build beams capable...
DEFF Research Database (Denmark)
leMesurier, B.J.; Christiansen, Peter Leth; Gaididei, Yuri Borisovich
2004-01-01
The effect of attractive linear potentials on self-focusing in-waves modeled by a nonlinear Schrodinger equation is considered. It is shown that the attractive potential can prevent both singular collapse and dispersion that are generic in the cubic Schrodinger equation in the critical dimension 2...... losses, and known stable periodic behavior of certain solutions in the presence of attractive potentials....
Nonlinear control of turbulence and velocity space diffusion in beam plasma systems. Final report
International Nuclear Information System (INIS)
Walsh, J.E.
1975-01-01
Results of low energy electron beam-plasma heating experiments are discussed. A figure of merit which can be used to compare different beam heating experiments is presented. Some general observations about the possibility of useful beam plasma heating are mentioned. (U.S.)
Kanagawa, Tetsuya
2015-05-01
This paper theoretically treats the weakly nonlinear propagation of diffracted sound beams in nonuniform bubbly liquids. The spatial distribution of the number density of the bubbles, initially in a quiescent state, is assumed to be a slowly varying function of the spatial coordinates; the amplitude of variation is assumed to be small compared to the mean number density. A previous derivation method of nonlinear wave equations for plane progressive waves in uniform bubbly liquids [Kanagawa, Yano, Watanabe, and Fujikawa (2010). J. Fluid Sci. Technol. 5(3), 351-369] is extended to handle quasi-plane beams in weakly nonuniform bubbly liquids. The diffraction effect is incorporated by adding a relation that scales the circular sound source diameter to the wavelength into the original set of scaling relations composed of nondimensional physical parameters. A set of basic equations for bubbly flows is composed of the averaged equations of mass and momentum, the Keller equation for bubble wall, and supplementary equations. As a result, two types of evolution equations, a nonlinear Schrödinger equation including dissipation, diffraction, and nonuniform effects for high-frequency short-wavelength case, and a Khokhlov-Zabolotskaya-Kuznetsov equation including dispersion and nonuniform effects for low-frequency long-wavelength case, are derived from the basic set.
International Nuclear Information System (INIS)
Claxton, L.D.; Houk, V.S.; Williams, R.; Kremer, F.
1991-01-01
Due to the consideration of bioremediation for oil spills, it is important to understand the ecological and human health implications of bioremediation efforts. During biodegradation, the toxicity of the polluting material may actually increase upon the conversion of non-toxic constituents to toxic species. Also, toxic compounds refractory to biological degradation may compromise the effectiveness of the treatment technique. In the study, the Salmonella mutagenicity assay showed that both the Prudhoe Bay crude oil and its weathered counterpart collected from oil-impacted water were weakly mutagenic. Results also showed that the mutagenic components were depleted at a faster rate than the overall content of organic material
International Nuclear Information System (INIS)
Collitt, R.
1997-01-01
High production, transport and refining costs have long led oil companies to shun heavy crude oils. Advances in the technology of upgrading heavy oils, however, are likely to reduce transport costs and improve the refinery output. Research and development by Venezuela's state oil company, Petroleos de Venezuela (PDVSA), has resulted in a process called Aquaconversion which permits the upgrading of heavy crude oils using a catalyst and the hydrogen from steam. This may be carried out at the wellhead in small low-pressure and relatively inexpensive units. In addition, higher distillate yields of higher value could be produced by revamping the thermal cracking units of refineries to incorporate the new technology. This has generated considerable interest in Venezuela's large extra-heavy crude oil reserves and has led multinational oil companies along with PDVSA to pledge $17 billion to their development. Even at a $2 to $3 per barrel upgrading cost, Venezuela's extra heavy crudes are competitive with lighter oils from other countries. Other major markets for the new technology are likely to be China and Russia, given their own large heavy crude reserves. (UK)
Amine-based post-combustion CO2 capture in air-blown IGCC systems with cold and hot gas clean-up
International Nuclear Information System (INIS)
Giuffrida, A.; Bonalumi, D.; Lozza, G.
2013-01-01
Highlights: • Hot fuel gas clean-up is a very favorable technology for IGCC concepts. • IGCC net efficiency reduces to 41.5% when realizing post-combustion CO 2 capture. • Complex IGCC layouts are necessary if exhaust gas recirculation is realized. • IGCC performance does not significantly vary with exhaust gas recirculation. - Abstract: This paper focuses on the thermodynamic performance of air-blown IGCC systems with post-combustion CO 2 capture by chemical absorption. Two IGCC technologies are investigated in order to evaluate two different strategies of coal-derived gas clean-up. After outlining the layouts of two power plants, the first with conventional cold gas clean-up and the second with hot gas clean-up, attention is paid to the CO 2 capture station and to issues related to exhaust gas recirculation in combined cycles. The results highlight that significant improvements in IGCC performance are possible if hot coal-derived gas clean-up is realized before the syngas fuels the combustion turbine, so the energy cost of CO 2 removal in an amine-based post-combustion mode is less strong. In particular, IGCC net efficiency as high as 41.5% is calculated, showing an interesting potential if compared to the one of IGCC systems with pre-combustion CO 2 capture. Thermodynamic effects of exhaust gas recirculation are investigated as well, even though IGCC performance does not significantly vary against a more complicated plant layout
International Nuclear Information System (INIS)
Bohn, C.L.; Piot, P.; Erdelyi, B.
2008-01-01
According to its original Statement of Work (SOW), the overarching objective of this project is: 'To enhance substantially the understanding of the fundamental dynamics of nonequilibrium high-brightness beams with space charge.' Our work and results over the past three and half years have been both intense and fruitful. Inasmuch as this project is inextricably linked to a larger, growing research program - that of the Beam Physics and Astrophysics Group (BPAG) - the progress that it has made possible cannot easily be separated from the global picture. Thus, this summary report includes major sections on 'global' developments and on those that can be regarded as specific to this project.
International Nuclear Information System (INIS)
Aggarwal, Munish; Vij, Shivani; Kant, Niti
2015-01-01
The propagation of quadruple Gaussian laser beam in a plasma characterized by axial inhomogeneity and nonlinearity due to ponderomotive force in the paraxial ray approximation is investigated. An appropriate expression for the nonlinear dielectric constant has been developed in the presence of external magnetic field, with linear absorption and due to saturation effects for arbitrary large intensity. The effects of different types of plasma axial inhomogeneities on self-focusing of laser beam have been studied with the typical laser and plasma parameters. Self-focusing of quadruple Gaussian laser beam in the presence of externally applied magnetic field and saturating parameter is found significantly improved in the case of extraordinary mode. Our results reveal that initially converging beam shows oscillatory convergence whereas initially diverging beam shows oscillatory divergence. The beam is more focussed at lower intensity in both cases viz. extraordinary and ordinary mode. (paper)
Zhao, Chen-Guang; Tan, Jiu-Bin; Liu, Tao
2010-09-01
The mechanism of a non-polarizing beam splitter (NPBS) with asymmetrical transfer coefficients causing the rotation of polarization direction is explained in principle, and the measurement nonlinear error caused by NPBS is analyzed based on Jones matrix theory. Theoretical calculations show that the nonlinear error changes periodically, and the error period and peak values increase with the deviation between transmissivities of p-polarization and s-polarization states. When the transmissivity of p-polarization is 53% and that of s-polarization is 48%, the maximum error reaches 2.7 nm. The imperfection of NPBS is one of the main error sources in simultaneous phase-shifting polarization interferometer, and its influence can not be neglected in the nanoscale ultra-precision measurement.
Uclés, Ana; Herrera López, Sonia; Dolores Hernando, Maria; Rosal, Roberto; Ferrer, Carmen; Fernández-Alba, Amadeo R
2015-11-01
The use of yttria-stabilized zirconium dioxide nanoparticles as d-SPE clean-up sorbent for a rapid and sensitive liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method for the determination of post-harvest fungicides (carbaryl, carbendazim, chlorpropham, diphenylamine, ethoxyquin, flutriafol, imazalil, iprodione, methomyl, myclobutanil, pirimiphos-methyl, prochloraz, pyrimethanil, thiabendazole, thiophanate-methyl and tolclofos-methyl) in orange and pear samples has been evaluated and validated. The sample preparation was a modification of the QuEChERS extraction method using yttria-stabilized zirconium dioxide and multi-walled carbon nanotubes (MWCNTs) nanoparticles as the solid phase extraction (d-SPE) clean-up sorbents prior to injecting the ten-fold diluted extracts into the LC system. By using the yttria-stabilized zirconium dioxide extraction method, more recoveries in the 70-120% range were obtained - thus this method was used for the validation. Quantification was carried out using a matrix-matched calibration curve which was linear in the 1-500 µg kg(-1) range for almost all the pesticides studied. The validated limit of quantification was 10 µg kg(-1) for most of the studied compounds, except chlorpropham, ethoxyquin and thiophanate-methyl. Pesticide recoveries at the 10 and 100 µg kg(-1) concentration levels were satisfactory, with values between 77% and 120% and relative standard deviations (RSD) lower than 10% (n=5). The developed method was applied for the determination of selected fungicides in 20 real orange and pear samples. Four different pesticide residues were detected in 10 of these commodities; 20% of the samples contained pesticide residues at a quantifiable level (equal to or above the LOQs) for at least one pesticide residue. The most frequently-detected pesticide residues were: carbendazim, thiabendazole and imazalil-all were below the MRL. The highest concentration found was imazalil at 1175 µg kg
Extension of non-linear beam models with deformable cross sections
Sokolov, I.; Krylov, S.; Harari, I.
2015-12-01
Geometrically exact beam theory is extended to allow distortion of the cross section. We present an appropriate set of cross-section basis functions and provide physical insight to the cross-sectional distortion from linear elastostatics. The beam formulation in terms of material (back-rotated) beam internal force resultants and work-conjugate kinematic quantities emerges naturally from the material description of virtual work of constrained finite elasticity. The inclusion of cross-sectional deformation allows straightforward application of three-dimensional constitutive laws in the beam formulation. Beam counterparts of applied loads are expressed in terms of the original three-dimensional data. Special attention is paid to the treatment of the applied stress, keeping in mind applications such as hydrogel actuators under environmental stimuli or devices made of electroactive polymers. Numerical comparisons show the ability of the beam model to reproduce finite elasticity results with good efficiency.
Nonlinear propagation of an elliptically shaped Gaussian laser beam in an overdense plasma
Energy Technology Data Exchange (ETDEWEB)
Nayyar, V P; Soni, V S [Punjabi Univ., Patiala (India). Dept. of Physics
1979-04-01
The self-focusing and self defocusing of an elliptically shaped high power laser beam in an extradense plasma is discussed. On account of the ponderomotive force induced by the spatial variation of irradiance in the transverse plane, an electron density gradient is created in the overdense plasma where the beam can penetrate. Self-focusing of the beam in the x and y directions for different critical powers has been extensively studied.
International Nuclear Information System (INIS)
Singh, Kh.I.; Das, G.C.
1993-01-01
Soliton propagations are studied in a relativistic multicomponent ion-beam plasma through the derivation of Korteweg-deVries (K-dV) and modified K-dV (mK-dV) equations. A generalization of the mK-dV equation involving higher order nonlinearities gives a transitive link between the K-dV and mK-dV equations for isothermal plasma, and the validity of this generalized equation throughout the whole range of negative ion concentrations is investigated through the derivation of Sagdeev potential. Parallel discussion of various K-dV solitons enlightening the experimental implications is also made. (author). 22 refs
International Nuclear Information System (INIS)
Zahran, M.A.; El-Shewy, E.K.
2008-01-01
The nonlinear properties of solitary wave structures are reported in an unmagnetized collisionless plasma comprising of cold relativistic electron fluid, Maxwellian hot electrons, relativistic electron beam, and stationary ions. The Korteweg--de Vries (KdV) equation has been derived using a reductive perturbation theory. As the wave amplitude increases, the width and velocity of the soliton deviate from the prediction of the KdV equation i.e. the breakdown of the KdV approximation. On the other hand, to overcome this weakness we extend our analysis to obtain the KdV equation with fifth-order dispersion term. The solution of the resulting equation has been obtained
International Nuclear Information System (INIS)
Ressel, K.
1993-06-01
Halogen hydrocarbons and above all chlorinated hydrocarbons are widespread harmful substances in soils and in groundwater. When cleaning up groundwater contamination, the contaminants are brought into the gas phase by strip processes. From the gas phase, the contaminants can be adsorbed on different carrier materials, mostly active carbon. One was searching for ways to regenerate this adsorption material. The mixed culture from a sea sediment most suitable for the decomposition of chlorinated hydrocarbons was optimized regarding its decomposition performance and was later used on the technical scale. In the decomposition experiments on the large technical scale, the cultures were lodged on filling bodies which has a much higher amount of gaps. In this case, an optimum supply of the micro-organisms with oxygen and methane is guaranteed, which is used as co-substrate. No intermediate product was found in a gas chromatography examination. The biologically occupied stage is situated between a desorption column and the active carbon filters, and reduces the load of harmful substances which can no longer be brought into the gas phase by stripping out. This has the advantage that it can be integrated in existing plants and can be adapted to any case of contamination by lodging adapted micro-organisms on it. The basis for each application must be separately researched. (orig.) [de
Bijttebier, Sebastiaan; D'Hondt, Els; Noten, Bart; Hermans, Nina; Apers, Sandra; Voorspoels, Stefan
2014-11-15
Alkaline saponification is often used to remove interfering chlorophylls and lipids during carotenoids analysis. However, saponification also hydrolyses esterified carotenoids and is known to induce artifacts. To avoid carotenoid artifact formation during saponification, Larsen and Christensen (2005) developed a gentler and simpler analytical clean-up procedure involving the use of a strong basic resin (Ambersep 900 OH). They hypothesised a saponification mechanism based on their Liquid Chromatography-Photodiode Array (LC-PDA) data. In the present study, we show with LC-PDA-accurate mass-Mass Spectrometry that the main chlorophyll removal mechanism is not based on saponification, apolar adsorption or anion exchange, but most probably an adsorption mechanism caused by H-bonds and dipole-dipole interactions. We showed experimentally that esterified carotenoids and glycerolipids were not removed, indicating a much more selective mechanism than initially hypothesised. This opens new research opportunities towards a much wider scope of applications (e.g. the refinement of oils rich in phytochemical content). Copyright © 2014 Elsevier Ltd. All rights reserved.
Directory of Open Access Journals (Sweden)
NURIL HIDAYATI
2009-09-01
Full Text Available Water contamination with heavy metals, mainly mercury and cyanide (CN due to small scale of public mines and large scale of industrial mines have been in concern to residents around the area. Surveys of heavy metal contamination in aquatic environments, such as rivers and paddy fields over two gold mine areas in West Jawa were conducted and possible solution of using indigenous plants for phytoremediation was studied. The results showed that most of the rivers and other aquatic environments were affected by gold mine activities. Rivers, ponds, and paddy fields around illegal public mines were mostly contaminated by mercury in considerably high levels, such as paddy fields in two locations (Nunggul and Leuwijamang, Pongkor were contaminated up to 22.68 and 7.73 ppm of Hg, respectively. Whereas rivers located around large scale industrial mines were contaminated by CN. Possible solution of cleaning up by using green technology of phytoremediation was examined. Some plant species grew in the contaminated sites showed high tolerance and potentially effective in accumulating cyanide or mercury in their roots and above ground portions. Lindernia crustacea (L. F.M., Digitaria radicosa (Presl Miq, Paspalum conjugatum, Cyperus kyllingia accumulated 89.13, 50.93, 1.78, and 0.77 ppm of Hg, respectively. Whereas, Paspalum conjugatum, Cyperus kyllingia accumulated 16.52 and 33. 16 ppm of CN respectively.
Liu, Zhiguo; Stromberg, David; Liu, Xuming; Liao, Wei; Liu, Yan
2015-03-21
A new multiple-stage treatment process was developed via integrating electrocoagulation with biogas pumping to simultaneously reclaim anaerobic digestion effluent and clean up biogas. The 1st stage of electrocoagulation treatment under the preferred reaction condition led to removal efficiencies of 30%, 81%, 37% and >99.9% for total solids, chemical oxygen demand, total nitrogen and total phosphorus, respectively. Raw biogas was then used as a reactant and pumped into the effluent to simultaneously neutralize pH of the effluent and remove H2S in the biogas. The 2nd stage of electrocoagulation treatment on the neutralized effluent showed that under the selected reaction condition, additional 60% and 10% of turbidity and chemical oxygen demand were further removed. The study concluded a dual-purpose approach for the first time to synergistically combine biogas purification and water reclamation for anaerobic digestion system, which well addresses the downstream challenges of anaerobic digestion technology. Copyright © 2014 Elsevier B.V. All rights reserved.
A probabilistic model estimating oil spill clean-up costs – A case study for the Gulf of Finland
International Nuclear Information System (INIS)
Montewka, Jakub; Weckström, Mia; Kujala, Pentti
2013-01-01
Highlights: • A model evaluating oil spill cleanup-costs for the Gulf of Finland is presented. • Bayesian Belief Networks are used to develop the model in a probabilistic fashion. • The results are compared with existing models and good agreement is found. • The model can be applicable for cost-benefit analysis in risk framework. -- Abstract: Existing models estimating oil spill costs at sea are based on data from the past, and they usually lack a systematic approach. This make them passive, and limits their ability to forecast the effect of the changes in the oil combating fleet or location of a spill on the oil spill costs. In this paper we make an attempt towards the development of a probabilistic and systematic model estimating the costs of clean-up operations for the Gulf of Finland. For this purpose we utilize expert knowledge along with the available data and information from literature. Then, the obtained information is combined into a framework with the use of a Bayesian Belief Networks. Due to lack of data, we validate the model by comparing its results with existing models, with which we found good agreement. We anticipate that the presented model can contribute to the cost-effective oil-combating fleet optimization for the Gulf of Finland. It can also facilitate the accident consequences estimation in the framework of formal safety assessment (FSA)
DEFF Research Database (Denmark)
Barari, Amin; Ganjavi, B.; Jeloudar, M. Ghanbari
2010-01-01
and fluid mechanics. Design/methodology/approach – Two new but powerful analytical methods, namely, He's VIM and HPM, are introduced to solve some boundary value problems in structural engineering and fluid mechanics. Findings – Analytical solutions often fit under classical perturbation methods. However......, as with other analytical techniques, certain limitations restrict the wide application of perturbation methods, most important of which is the dependence of these methods on the existence of a small parameter in the equation. Disappointingly, the majority of nonlinear problems have no small parameter at all......Purpose – In the last two decades with the rapid development of nonlinear science, there has appeared ever-increasing interest of scientists and engineers in the analytical techniques for nonlinear problems. This paper considers linear and nonlinear systems that are not only regarded as general...
Robust energy harvesting from walking vibrations by means of nonlinear cantilever beams
Kluger, Jocelyn M.; Sapsis, Themistoklis P.; Slocum, Alexander H.
2015-04-01
In the present work we examine how mechanical nonlinearity can be appropriately utilized to achieve strong robustness of performance in an energy harvesting setting. More specifically, for energy harvesting applications, a great challenge is the uncertain character of the excitation. The combination of this uncertainty with the narrow range of good performance for linear oscillators creates the need for more robust designs that adapt to a wider range of excitation signals. A typical application of this kind is energy harvesting from walking vibrations. Depending on the particular characteristics of the person that walks as well as on the pace of walking, the excitation signal obtains completely different forms. In the present work we study a nonlinear spring mechanism that is composed of a cantilever wrapping around a curved surface as it deflects. While for the free cantilever, the force acting on the free tip depends linearly on the tip displacement, the utilization of a contact surface with the appropriate distribution of curvature leads to essentially nonlinear dependence between the tip displacement and the acting force. The studied nonlinear mechanism has favorable mechanical properties such as low frictional losses, minimal moving parts, and a rugged design that can withstand excessive loads. Through numerical simulations we illustrate that by utilizing this essentially nonlinear element in a 2 degrees-of-freedom (DOF) system, we obtain strongly nonlinear energy transfers between the modes of the system. We illustrate that this nonlinear behavior is associated with strong robustness over three radically different excitation signals that correspond to different walking paces. To validate the strong robustness properties of the 2DOF nonlinear system, we perform a direct parameter optimization for 1DOF and 2DOF linear systems as well as for a class of 1DOF and 2DOF systems with nonlinear springs similar to that of the cubic spring that are physically realized
Awrejcewicz, J.; Krysko, V. A.; Yakovleva, T. V.; Pavlov, S. P.; Krysko, V. A.
2018-05-01
A mathematical model of complex vibrations exhibited by contact dynamics of size-dependent beam-plate constructions was derived by taking the account of constraints between these structural members. The governing equations were yielded by variational principles based on the moment theory of elasticity. The centre of the investigated plate was supported by a beam. The plate and the beam satisfied the Kirchhoff/Euler-Bernoulli hypotheses. The derived partial differential equations (PDEs) were reduced to the Cauchy problems by the Faedo-Galerkin method in higher approximations, whereas the Cauchy problem was solved using a few Runge-Kutta methods. Reliability of results was validated by comparing the solutions obtained by qualitatively different methods. Complex vibrations were investigated with the help of methods of nonlinear dynamics such as vibration signals, phase portraits, Fourier power spectra, wavelet analysis, and estimation of the largest Lyapunov exponents based on the Rosenstein, Kantz, and Wolf methods. The effect of size-dependent parameters of the beam and plate on their contact interaction was investigated. It was detected and illustrated that the first contact between the size-dependent structural members implies chaotic vibrations. In addition, problems of chaotic synchronization between a nanoplate and a nanobeam were addressed.
International Nuclear Information System (INIS)
Claeys, M.; Sinou, J.J.; Lambelin, J.P.; Alcoverro, B.
2014-01-01
This study presents a direct comparison of measured and predicted nonlinear vibrations of a clamped-clamped steel beam. A multi-harmonic comparison of simulations with measurements is performed at the vicinity of the primary resonance. First of all, a nonlinear analytical model of the beam is developed taking into account non-ideal boundary conditions. The Harmonic Balance Method is implemented to estimate the nonlinear behavior of the clamped-clamped beam. This nonlinear method enables to simulate the vibration stationary response of a nonlinear system projected on several harmonics. This study then proposes a method to compare numerical simulations with measurements on all these harmonics. A signal analysis tool is developed to extract the system harmonics' frequency responses from a temporal signal of a swept sine experiment. An evolutionary updating algorithm (Covariance Matrix Adaptation Evolution Strategy), coupled with highly selective filters is used to identify both fundamental frequency and harmonics' amplitude in the temporal signal, at every moment. This tool enables to extract the harmonic amplitudes of the output signal as well as the input signal. The input of the Harmonic Balance Method can then be either an ideal mono-harmonic signal or a multi-harmonic experimental input signal. Finally, the present work focuses on the comparison of experimental and simulated results. From experimental output harmonics and numerical simulations, it is shown that it is possible to distinguish the nonlinearities of the clamped-clamped beam and the effect of the non-ideal input signal. (authors)
International Nuclear Information System (INIS)
Davidson, R.C.; Chen, C.
1997-08-01
A kinetic description of intense nonneutral beam propagation through a periodic solenoidal focusing field B sol (rvec x) is developed. The analysis is carried out for a thin beam with characteristic beam radius r b much-lt S, and directed axial momentum γ b mβ b c (in the z-direction) large compared with the transverse momentum and axial momentum spread of the beam particles. Making use of the nonlinear Vlasov-Maxwell equations for general distribution function f b (rvec x,rvec p,t) and self-consistent electrostatic field consistent with the thin-beam approximation, the kinetic model is used to investigate detailed beam equilibrium properties for a variety of distribution functions. Examples are presented both for the case of a uniform solenoidal focusing field B z (z) = B 0 = const. and for the case of a periodic solenoidal focusing field B z (z + S) = B z (z). The nonlinear Vlasov-Maxwell equations are simplified in the thin-beam approximation, and an alternative Hamiltonian formulation is developed that is particularly well-suited to intense beam propagation in periodic focusing systems. Based on the present analysis, the Vlasov-Maxwell description of intense nonneutral beam propagation through a periodic solenoidal focusing field rvec B sol (rvec x) is found to be remarkably tractable and rich in physics content. The Vlasov-Maxwell formalism developed here can be extended in a straightforward manner to investigate detailed stability behavior for perturbations about specific choices of beam equilibria
Nonlinear plasma waves excitation by intense ion beams in background plasma
International Nuclear Information System (INIS)
Kaganovich, Igor D.; Startsev, Edward A.; Davidson, Ronald C.
2004-01-01
Plasma neutralization of an intense ion pulse is of interest for many applications, including plasma lenses, heavy ion fusion, cosmic ray propagation, etc. An analytical electron fluid model has been developed to describe the plasma response to a propagating ion beam. The model predicts very good charge neutralization during quasi-steady-state propagation, provided the beam pulse duration τ b is much longer than the electron plasma period 2π/ω p , where ω p =(4πe 2 n p /m) 1/2 is the electron plasma frequency, and n p is the background plasma density. In the opposite limit, the beam pulse excites large-amplitude plasma waves. If the beam density is larger than the background plasma density, the plasma waves break. Theoretical predictions are compared with the results of calculations utilizing a particle-in-cell (PIC) code. The cold electron fluid results agree well with the PIC simulations for ion beam propagation through a background plasma. The reduced fluid description derived in this paper can provide an important benchmark for numerical codes and yield scaling relations for different beam and plasma parameters. The visualization of numerical simulation data shows complex collective phenomena during beam entry and exit from the plasma
Nonlinear Plasma Waves Excitation by Intense Ion Beams in Background Plasma
International Nuclear Information System (INIS)
Kaganovich, Igor D.; Startsev, Edward A.; Davidson, Ronald C.
2004-01-01
Plasma neutralization of an intense ion pulse is of interest for many applications, including plasma lenses, heavy ion fusion, cosmic ray propagation, etc. An analytical electron fluid model has been developed to describe the plasma response to a propagating ion beam. The model predicts very good charge neutralization during quasi-steady-state propagation, provided the beam pulse duration τ b is much longer than the electron plasma period 2π/ω p , where ω p = (4πe 2 n p /m) 1/2 is the electron plasma frequency and n p is the background plasma density. In the opposite limit, the beam pulse excites large-amplitude plasma waves. If the beam density is larger than the background plasma density, the plasma waves break. Theoretical predictions are compared with the results of calculations utilizing a particle-in-cell (PIC) code. The cold electron fluid results agree well with the PIC simulations for ion beam propagation through a background plasma. The reduced fluid description derived in this paper can provide an important benchmark for numerical codes and yield scaling relations for different beam and plasma parameters. The visualization of numerical simulation data shows complex collective phenomena during beam entry and exit from the plasma
Reproducing the nonlinear dynamic behavior of a structured beam with a generalized continuum model
Vila, J.; Fernández-Sáez, J.; Zaera, R.
2018-04-01
In this paper we study the coupled axial-transverse nonlinear vibrations of a kind of one dimensional structured solids by application of the so called Inertia Gradient Nonlinear continuum model. To show the accuracy of this axiomatic model, previously proposed by the authors, its predictions are compared with numeric results from a previously defined finite discrete chain of lumped masses and springs, for several number of particles. A continualization of the discrete model equations based on Taylor series allowed us to set equivalent values of the mechanical properties in both discrete and axiomatic continuum models. Contrary to the classical continuum model, the inertia gradient nonlinear continuum model used herein is able to capture scale effects, which arise for modes in which the wavelength is comparable to the characteristic distance of the structured solid. The main conclusion of the work is that the proposed generalized continuum model captures the scale effects in both linear and nonlinear regimes, reproducing the behavior of the 1D nonlinear discrete model adequately.
Santos, E A; Vargas, E A
2002-05-01
An immunoaffinity clean-up-based method for determining ochratoxin A (OTA) in green coffee aiming at one-dimensional thin layer chromatography (TLC) analysis was established. OTA was extracted with a mixture of methanol and aqueous sodium hydrogen carbonate solution, purified through an immunoaffinity column, separated on normal or reversed-phase (RP) TLC plates and detected and quantified by visual and densitometric analysis. The linear equation of the standard calibration curve by densitometric analysis gave R(2) > 0.999 (0.04-84 ng). The mean recovery (R) of OTA from spiked samples (1.8-109 microg kg(-1)) by densitometric and visual analyses were 98.4 and 103.8%, respectively. The relative standard deviations (RSD) for densitometric and visual analysis varied from 1.1 to 24.9% and from 0.0 to 18.8%, respectively. The RSD for naturally contaminated samples by densitometry (three levels of contamination, n = 3) varied from 11.1 to 18.1%. The correlation (R(2)) between high-performance liquid chromatography (HPLC) and densitometry, and between visual and densitometric analysis for spiked samples were > 0.99. The limit of detection (LOD) of the method was 0.5 microg kg(-1) for normal TLC. Toluene-ethyl acetate-88% formic acid (6:3:1 v/v/v) and acetonitrile-methanol-water-glacial acetic acid (35:35:29:10 v/v/v/v) were regarded as the suitable TLC solvents for eluting both standards and samples on normal and RP TLC plates, respectively. Toluene-acetic acid (99:1 v/v) was chosen as the spotting solvent among several others for giving the best sensitivity and resolution of OTA on TLC plates as well as the best recovery of OTA from standard and sample extract residues. Preliminary studies were carried out to investigate the reuse of the immunoaffinity column and the interference of caffeine in the OTA recovery.
DEFF Research Database (Denmark)
Sørensen, Louise Marie; Nielsen, Kristian Fog; Jacobsen, Thomas
2008-01-01
A method for determination of mycophenolic acid (MPA) in dry-cured ham, fermented sausage and liver pate is described. MPA was extracted from meat with bicarbonate-acetonitrile, further cleaned-up by mixed mode reversed phase-anion exchange and detected using a LC-MS system with electrospray...
International Nuclear Information System (INIS)
Zvagule, T.; Bruvere, R.; Gabruseva, N.; Balodis, V.; Feldmane, G.
2002-01-01
Nearly 1% of the male population of Latvia (n∼6500) was sent (1986-1991) to Chernobyl to assist in the clean-up activities after the nuclear power plant accident (1986). The disease incidence, dynamic of appearance of the key symptoms, and interferon status were evaluated in relation to time of work, duration of work, and type of work, in the whole clean-up worker group and in specific group with seizures of unconsciousness (n=321). The disease incidence in clean-up workers from Latvia exceeds that observed in an age- and sex-matched male population. Most had several diseases each and their multiple symptoms exhibited a tendency to progress even 10-14 years after the exposure (during 1996-2000). Diseases of the nervous, digestive and circulatory systems, mental disorders, and diseases of muscles and connective tissue were the most frequent. The primary outset of symptoms was low in the first 2-3 years after the work, and gradually increased during the following 10-12 years. Leucopoenia was predominant in 1990-1993 and leucocytosis in 1997-2000. The ability of leucocytes to produce interferons was significantly decreased. Since the external radiation doses did not exceed 50 centigray (cGy) there was sufficient reason to believe that the man cause of the gradually increased frequency of health problems was a permanent radiation and toxic compounds source from the long-life radioisotopes incorporated in the clean-up workers bodies. (authors)
International Nuclear Information System (INIS)
Shlyakhova, N.V.
2009-01-01
The changes in the immune system involving all links of the immunity are three times more frequent in children whose fathers participated in Chornobyl accident clean-up. Disorders of humoral and phagocyte links are gender-dependent. Significant difference in the level of immunological parameters depending on the year of the father's stay in the zone was not revealed.
A liquid chromatography based method to detect citrinin in corn was developed using molecularly imprinted solid phase extraction (MISPE) sample clean-up. Molecularly imprinted polymers were synthesized using 1,4-dihydroxy-2-naphthoic acid as the template and an amine functional monomer. Density func...
Directory of Open Access Journals (Sweden)
Ana Andreea CIOCA
2017-05-01
Full Text Available The present work describes the development of a new, automatic High Performance Liquid Chromatography (HPLC Clean-up step, in the methodology of sample preparation and multi-residue determination of organochlorine compounds (OCs in fish meat. 24 OCs were taken into study. In addition 7 Polychlorinated Biphenyls (PCBs, 7 chlorobenzene compounds and one 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD were investigated. The HPLC conditions were established in accordance with the validated traditional Clean-up step of the laboratory. The technique was applied on a dilution of analytes of interest in order to establish the period of time in which the compounds are eluted. Another set of experiments involved fish oil, in order to identify and separate the fat fraction from the analytes. To confirm the findings of the experiments mentioned above, extracts of fish samples obtained after Accelerated Solvent Extraction (ASE were examined. The samples were spiked with the analytes of interest before HPLC clean-up step and quantified through Gas Chromatography coupled with tandem Mass Spectrometry (GC-MS/MS. A HPLC clean-up technique lasting 38 minutes/sample was developed. The method is not suitable for OCs such as Endosulfansulfat and Endrine Ketone due to the very low recovery results.Â
International Nuclear Information System (INIS)
Korenjev, M.M.; Kostenko, T.O.; Borisko, G.O.; Kalmikova, N.V.; Cherevatova, S. Kh.; Bondarenko, V.L.
2010-01-01
The state of the cardiovascular system of the adolescents aged 16-18 born from the parents who participated in Chornobyl accident clean-up was characterized by a high incidence of myocardium bioelectric activity disorders, presence of congenital small heart defects, widening of the left ventricle cavity, reduction of contractile function and myocardium tolerance to physical load.
Directory of Open Access Journals (Sweden)
Ratchata Theinchai
2016-01-01
Full Text Available We investigate semianalytical solutions of Euler-Bernoulli beam equation by using Laplace transform and Adomian decomposition method (LADM. The deformation of a uniform flexible cantilever beam is formulated to initial value problems. We separate the problems into 2 cases: integer order for small deformation and fractional order for large deformation. The numerical results show the approximated solutions of deflection curve, moment diagram, and shear diagram of the presented method.
Theinchai, Ratchata; Chankan, Siriwan; Yukunthorn, Weera
2016-01-01
We investigate semianalytical solutions of Euler-Bernoulli beam equation by using Laplace transform and Adomian decomposition method (LADM). The deformation of a uniform flexible cantilever beam is formulated to initial value problems. We separate the problems into 2 cases: integer order for small deformation and fractional order for large deformation. The numerical results show the approximated solutions of deflection curve, moment diagram, and shear diagram of the presented method.
Nonlinear behavior of capacitive micro-beams based on strain gradient theory
International Nuclear Information System (INIS)
Fathalilou, Mohammad; Sadeghi, Morteza; Rezazadeh, Ghader
2014-01-01
This paper studies the size dependent behavior of materials in MEMS structures. This behavior becomes noticeable for a structure when the characteristic size such as thickness or diameter is close to its internal length-scale parameter and is insignificant for the high ratio of the characteristic size to the length-scale parameter, which is the case of the silicon base micro-beams. However, in some types of micro-beams like gold or nickel bases, the size dependent effect cannot be overlooked. In such cases, ignoring this behavior in modeling will lead to incorrect results. Some previous researchers have applied classic beam theory on their models and imposed a considerable hypothetical value of residual stress to match their theoretical results with the experimental ones. The equilibrium positions or fixed points of the gold and nickel micro-beams are obtained and shown that for a given DC voltage, there is a considerable difference between the obtained fixed points using classic beam theory, modified couple stress theory, and modified strain gradient theory. In addition, it is shown that the calculated static and dynamic pull-in voltages using higher order theories are much closer to the experimental results and are higher several times than those obtained by classic beam theory.
Directory of Open Access Journals (Sweden)
Edward A. Startsev
2003-08-01
Full Text Available In plasmas with strongly anisotropic distribution functions (T_{∥b}/T_{⊥b}≪1 a Harris-like collective instability may develop if there is sufficient coupling between the transverse and longitudinal degrees of freedom. Such anisotropies develop naturally in accelerators and may lead to a deterioration of beam quality. This paper extends previous numerical studies [E. A. Startsev, R. C. Davidson, and H. Qin, Phys. Plasmas 9, 3138 (2002] of the stability properties of intense non-neutral charged particle beams with large temperature anisotropy (T_{⊥b}≫T_{∥b} to allow for nonaxisymmetric perturbations with ∂/∂θ≠0. The most unstable modes are identified, and their eigenfrequencies, radial mode structure, and nonlinear dynamics are determined. The simulation results clearly show that moderately intense beams with s_{b}=ω[over ^]_{pb}^{2}/2γ_{b}^{2}ω_{β⊥}^{2}≳0.5 are linearly unstable to short-wavelength perturbations with k_{z}^{2}r_{b}^{2}≳1, provided the ratio of longitudinal and transverse temperatures is smaller than some threshold value. Here, ω[over ^]_{pb}^{2}=4πn[over ^]_{b}e_{b}^{2}/γ_{b}m_{b} is the relativistic plasma frequency squared, and ω_{β⊥} is the betatron frequency associated with the applied smooth-focusing field. A theoretical model is developed based on the Vlasov-Maxwell equations which describes the essential features of the linear stages of instability. Both the simulations and the analytical theory predict that the dipole mode (azimuthal mode number m=1 is the most unstable mode. In the nonlinear stage, tails develop in the longitudinal momentum distribution function, and the kinetic instability saturates due to resonant wave-particle interactions.
Nonlinear finite element analysis of reinforced and prestressed concrete shells with edge beams
International Nuclear Information System (INIS)
Srinivasa Rao, P.; Duraiswamy, S.
1994-01-01
The structural design of reinforced and prestressed concrete shells demands the application of nonlinear finite element analysis (NFEM) procedures to ensure safety and serviceability. In this paper the details of a comprehensive NFEM program developed are presented. The application of the program is highlighted by solving two numerical problems and comparing the results with experimental results. (author). 20 refs., 15 figs
Giant nonlinear interaction between two optical beams via a quantum dot embedded in a photonic wire
DEFF Research Database (Denmark)
Nguyen, H.A.; Grange, T.; Reznychenko, B.
2018-01-01
a tailored photonic environment. Here, we demonstrate a two-mode giant nonlinearity with a single semiconductor quantum dot (QD) embedded in a photonic wire antenna. We exploit two detuned optical transitions associated with the exciton-biexciton QD level scheme. Owing to the broadband waveguide antenna...
Andreaus, Ugo; Spagnuolo, Mario; Lekszycki, Tomasz; Eugster, Simon R.
2018-04-01
We present a finite element discrete model for pantographic lattices, based on a continuous Euler-Bernoulli beam for modeling the fibers composing the pantographic sheet. This model takes into account large displacements, rotations and deformations; the Euler-Bernoulli beam is described by using nonlinear interpolation functions, a Green-Lagrange strain for elongation and a curvature depending on elongation. On the basis of the introduced discrete model of a pantographic lattice, we perform some numerical simulations. We then compare the obtained results to an experimental BIAS extension test on a pantograph printed with polyamide PA2200. The pantographic structures involved in the numerical as well as in the experimental investigations are not proper fabrics: They are composed by just a few fibers for theoretically allowing the use of the Euler-Bernoulli beam theory in the description of the fibers. We compare the experiments to numerical simulations in which we allow the fibers to elastically slide one with respect to the other in correspondence of the interconnecting pivot. We present as result a very good agreement between the numerical simulation, based on the introduced model, and the experimental measures.
Linear and nonlinear ion beam instabilities in a double plasma device
International Nuclear Information System (INIS)
Lee, S.G.; Diebold, D.; Hershkowitz, N.
1994-01-01
Ion beam instabilities in the double plasma device DOLI-1 were found to be quite sensitive to the difference between the source and target chamber plasma potentials when those potentials were within an electron temperature T e /e or so of each other. When the target chamber plasma potential of DOLI-1 was ≤ T e /e more positive than the source chamber plasma potential, a global ion beam-ion beam instability was observed. On the other hand, when the maximum target potential was between approximately 0.5 T e /e and 2.0 T e /e below the source potential, an ion-ion beam instability and a soliton associated with it were observed. This soliton is unique in that it is not launched but rather is self generated by the plasma and beam. When the target potential was less than source potential by more than two or so T e /e, the plasma was quite quiescent, which allowed small amplitude wave packet launched by Langmuir probe to be detected
Abd El Baky, Hussien
This research work is devoted to theoretical and numerical studies on the flexural behaviour of FRP-strengthened concrete beams. The objectives of this research are to extend and generalize the results of simple experiments, to recommend new design guidelines based on accurate numerical tools, and to enhance our comprehension of the bond performance of such beams. These numerical tools can be exploited to bridge the existing gaps in the development of analysis and modelling approaches that can predict the behaviour of FRP-strengthened concrete beams. The research effort here begins with the formulation of a concrete model and development of FRP/concrete interface constitutive laws, followed by finite element simulations for beams strengthened in flexure. Finally, a statistical analysis is carried out taking the advantage of the aforesaid numerical tools to propose design guidelines. In this dissertation, an alternative incremental formulation of the M4 microplane model is proposed to overcome the computational complexities associated with the original formulation. Through a number of numerical applications, this incremental formulation is shown to be equivalent to the original M4 model. To assess the computational efficiency of the incremental formulation, the "arc-length" numerical technique is also considered and implemented in the original Bazant et al. [2000] M4 formulation. Finally, the M4 microplane concrete model is coded in FORTRAN and implemented as a user-defined subroutine into the commercial software package ADINA, Version 8.4. Then this subroutine is used with the finite element package to analyze various applications involving FRP strengthening. In the first application a nonlinear micromechanics-based finite element analysis is performed to investigate the interfacial behaviour of FRP/concrete joints subjected to direct shear loadings. The intention of this part is to develop a reliable bond--slip model for the FRP/concrete interface. The bond
Gap Dependent Bifurcation Behavior of a Nano-Beam Subjected to a Nonlinear Electrostatic Pressure
Directory of Open Access Journals (Sweden)
Mohammad Fathalilou
Full Text Available This paper presents a study on the gap dependent bifurcation behavior of an electro statically-actuated nano-beam. The sizedependent behavior of the beam was taken into account by applying the couple stress theory. Two small and large gap distance regimes have been considered in which the intermolecular vdW and Casimir forces are dominant, respectively. It has been shown that changing the gap size can affect the fundamental frequency of the beam. The bifurcation diagrams for small gap distance revealed that by changing the gap size, the number and type of the fixed points can change. However, for large gap regime, where the Casimir force is the dominant intermolecular force, changing the gap size does not affect the quality of the bifurcation behavior.
Nonlinear analysis of flexible beams undergoing large rotations Via symbolic computations
Directory of Open Access Journals (Sweden)
Yuan Xiaofeng
2001-01-01
Full Text Available In this paper, a two-stage approach is presented for analyzing flexible beams undergoing large rotations. In the first stage, the symbolic forms of equations of motion and the Jacobian matrix are generated by means of MATLAB and written into a MATLAB script file automatically, where the flexible beams are described by the unified formulation presented in our previous paper. In the second stage, the derived equations of motion are solved by means of implicit numerical methods. Several comparison computations are performed. The two-stage approach proves to be much more efficient than pure numerical one.
Janiszewska-Olszowska, Joanna; Tandecka, Katarzyna; Szatkiewicz, Tomasz; Stępień, Piotr; Sporniak-Tutak, Katarzyna; Grocholewicz, Katarzyna
2015-11-18
The present study aimed at 3D analysis of adhesive remnants and enamel loss following the debonding of orthodontic molar tubes and orthodontic clean-up to assess the effectiveness and safety of One-Step Finisher and Polisher and Adhesive Residue Remover in comparison to tungsten carbide bur. Thirty human molars were bonded with chemical-cure orthodontic adhesive (Unite, 3M, USA), stored 24 h in 0.9 % saline solution, debonded and cleaned using three methods (Three groups of ten): tungsten carbide bur (Dentaurum, Pforzheim, Germany), one-step finisher and polisher (One gloss, Shofu Dental, Kyoto, Japan) and Adhesive Residue Remover (Dentaurum, Pforzheim, Germany). Direct 3D scanning in blue-light technology to the nearest 2 μm was performed before etching and after adhesive removal. Adhesive remnant height and volume as well as enamel loss depth and volume were calculated. An index of effectiveness and safety was proposed and calculated for every tool; adhesive remnant volume and duplicated enamel lost volume were divided by a sum of multiplicands. Comparisons using parametric ANOVA or nonparametric ANOVA rank Kruskal-Wallis tests were used to compare between tools for adhesive remnant height and volume, enamel loss depth and volume as well as for the proposed index. No statistically significant differences in the volume (p = 0.35) or mean height (p = 0.24) of adhesive remnants were found (ANOVA rank Kruskal-Wallis test) between the groups of teeth cleaned using different tools. Mean volume of enamel loss was 2.159 mm(3) for tungsten carbide bur, 1.366 mm(3) for Shofu One Gloss and 0.659 mm(3) for Adhesive Residue Remover - (F = 2.816, p = 0.0078). A comparison of the proposed new index between tools revealed highly statistically significant differences (p = 0.0081), supporting the best value for Adhesive Residue Remover and the worst - for tungsten carbide bur. The evaluated tools were all characterized by similar effectiveness. The most
Nonlinear analysis and analog simulation of a piezoelectric buckled beam with fractional derivative
Mokem Fokou, I. S.; Buckjohn, C. Nono Dueyou; Siewe Siewe, M.; Tchawoua, C.
2017-08-01
In this article, an analog circuit for implementing fractional-order derivative and a harmonic balance method for a vibration energy harvesting system under pure sinusoidal vibration source is proposed in order to predict the system response. The objective of this paper is to discuss the performance of the system with fractional derivative and nonlinear damping (μb). Bifurcation diagram, phase portrait and power spectral density (PSD) are provided to deeply characterize the dynamics of the system. These results are corroborated by the 0-1 test. The appearance of the chaotic vibrations reduces the instantaneous voltage. The pre-experimental investigation is carried out through appropriate software electronic circuit (Multisim). The corresponding electronic circuit is designed, exhibiting periodic and chaotic behavior, in accord with numerical simulations. The impact of fractional derivative and nonlinear damping is presented with detail on the output voltage and power of the system. The agreement between numerical and analytical results justifies the efficiency of the analytical technique used. In addition, by combining the harmonic excitation with the random force, the stochastic resonance phenomenon occurs and improves the harvested energy. It emerges from these results that the order of fractional derivative μ and nonlinear damping μb play an important role in the response of the system.
ALICE EMCal Reconstructable Energy Non-Linearity From Test Beam Monte Carlo
Carter, Thomas Michael
2017-01-01
Calorimeters play many important roles in modern high energy physics detectors, such as event selection, triggering, and precision energy measurements. EMCal, in the case of the ALICE experiment provides triggering on high energy jets, improves jet quenching study measurement bias and jet energy resolution, and improves electron and photon measurements [3]. With the EMCal detector in the ALICE experiment taking on so many important roles, it is important to fully understand, characterize and model its interactions with particles. In 2010 SPS and PS electron test beam measurements were performed on an EMCal mini-module [2]. Alongside this, the test beam setup and geometry was recreated in Geant4 by Nico [1]. Figure 1 shows the reconstructable energy linearity for the SPS test beam data and that obtained from the test beam monte carlo, indicating the amount of energy deposit as hits in the EMCal module. It can be seen that for energies above ∼ 100 GeV there is a signiﬁcant drop in the reconstructableenergym...
Energy Technology Data Exchange (ETDEWEB)
Welsch, Dominic Markus
2010-03-10
The High-Energy Storage Ring (HESR) is part of the upcoming Facility for Antiproton and Ion Research (FAIR) which is planned as a major extension to the present facility of the Helmholtzzentrum fuer Schwerionenforschung (GSI) in Darmstadt. The HESR will provide antiprotons in the momentum range from 1.5 to 15 GeV/c for the internal target experiment PANDA. The demanding requirements of PANDA in terms of beam quality and luminosity together with a limited production rate of antiprotons call for a long beam life time and a minimum of beam loss. Therefore, an effective closed orbit correction and a sufficiently large dynamic aperture of the HESR are crucial. With this thesis I present my work on both of these topics. The expected misalignments of beam guiding magnets have been estimated and used to simulate the closed orbit in the HESR. A closed orbit correction scheme has been developed for different ion optical settings of the HESR and numerical simulations have been performed to validate the scheme. The proposed closed orbit correction method which uses the orbit response matrix has been benchmarked at the Cooler Synchrotron COSY of the Forschungszentrum Juelich. A chromaticity correction scheme for the HESR consisting of sextupole magnets has been developed to reduce tune spread and thus to minimize the emittance growth caused by betatron resonances. The chromaticity correction scheme has been optimized through dynamic aperture calculations. The estimated field errors of the HESR dipole and quadrupole magnets have been included in the non-linear beam dynamics studies. Investigations concerning their optimization have been carried out. The ion optical settings of the HESR have been improved using dynamic aperture calculations and the technique of frequency map analysis. The related diffusion coefficient was also used to predict long-term stability based on short-term particle tracking. With a reasonable reduction of the quadrupole magnets field errors and a
Trevisan, Maria Teresa Salles; Owen, Robert Wyn; Calatayud-Vernich, Pau; Breuer, Andrea; Picó, Yolanda
2017-08-25
An analytical method using a quick, easy, cheap, effective, rugged and safe (QuEChERS) procedure for multi-residue determination of 52 pesticides in coffee leaf extractshas been developed and validated according to SANTE/11945/2015 guidelines. Different sorbent combinations for dispersive solid phase extraction (d-SPE) clean-up as well as dispersive liquid-liquid microextraction (DLLME) were tested. The relative standard deviations (RSDs) for the recovery of 87-94% of pesticides added to coffee leaf extracts,was ≤20% for samples spiked at concentrations up to 50ng*g -1 depending on the clean-up procedures. However, samples spiked with a 100ng*g -1 pesticide mixture gave RSDs>20% for most pesticides when d-SPE was carried out adding Supelclean ENVI-Carb 120/400. To explain this fact,the secondary metabolic profile was analyzed in all the extraction and clean-up procedures. Only in the clean-up procedure with the addition of Supel QuE Z-Sep+, does caffeine show a constant adsorption between blank and spiked samples. In other clean-up procedures, the amount of caffeine was higher in those samples spiked with pesticides. This indicates competition between caffeine and pesticides for adsorption to the sorbent. Addition of Supel QuE Z-Sep+ to the procedure revealed only a 32% matrix effect, whereas using PSA+ C18 the matrix effect was close to 97%. The process efficiency is up to 54% with the addition of Supel QuE Z-Sep+ and just up to 7% for the other clean-up procedures. The method was successfully tested in coffee leaves from different types of cultivars. Pesticides were not detected in organic coffee leaf extracts, but thiametoxan was clearly detected in 50% of coffee leaf extracts harvested from coffee trees grown under traditional conditions as determined by UHPLC-TOFMSLC/QqTOF-MS/MS. Copyright © 2017 Elsevier B.V. All rights reserved.
A non-linear procedure for the numerical analysis of crack development in beams failing in shear
Directory of Open Access Journals (Sweden)
P. Bernardi
2016-01-01
Full Text Available In this work, a consistent formulation for the representation of concrete behavior before and after cracking has been implemented into a non-linear model for the analysis of reinforced concrete structures, named 2D-PARC. Several researches have indeed pointed out that the adoption of an effective modeling for concrete, combined with an accurate failure criterion, is crucial for the correct prediction of the structural behavior, not only in terms of failure load, but also with reference to a realistic representation of crack initiation and development. This last aspect is particularly relevant at serviceability conditions in order to verify the fulfillment of structural requirements provided by Design Codes, which limit the maximum crack width due to appearance and durability issues. In more details, a constitutive model originally proposed by Ottosen and based on non-linear elasticity has been here incorporated into 2D-PARC in order to improve the numerical efficiency of the adopted algorithm, providing at the same time an accurate prediction of the structural response. The effectiveness of this procedure has been verified against significant experimental results available in the technical literature and relative to reinforced concrete beams without stirrups failing in shear, which represent a problem of great theoretical and practical importance in the field of structural engineering. Numerical results have been compared to experimental evidences not only in terms of global structural response (i.e. applied load vs. midspan deflection, but also in terms of crack pattern evolution and maximum crack widths.
International Nuclear Information System (INIS)
Sharma, Akanshu; Reddy, G.R.; Vaze, K.K.; Ghosh, A.K.; Kushwaha, H.S.
2009-07-01
It is now a well-known fact that beam-column connections are one of the most vulnerable zones of a reinforced concrete framed structure subjected to seismic loads. Under dynamic reversing loading, as in case of earthquakes, the inelastic hysteretic behavior of the members joining at these joints provides major contribution towards absorbing the external energy. The energy absorption capacity of a joint mainly depends on the ductility, i.e. capacity to undergo large displacements beyond yield, without significant strength degradation, of the members and the joint itself. Even if the members possess sufficient ductile behavior, the overall ductility of the joint is not warranted, until and unless the joint core itself has capacity to withstand large joint shear forces. Else, the joint core itself fails prematurely and leads to poor performance of the sub-assemblage. Another major objective of this program was to develop a simple yet effective analysis procedure that can closely predict the load-displacement behavior of the joints. Nonlinear dynamic analysis, although effective, is highly time consuming and complex. Resorting to such complex analysis is not encouraging to the practicing civil engineers or even researchers. However, as more and more emphasis is laid on nonlinear analysis and performance based design, nonlinear static pushover analysis is one such tool that is simple and effective and many researchers and engineers are getting encouraged to follow this analytical method. This report includes complete details of all the joints tested and their analysis. It gives complete theoretical formulations and assumptions used in the analysis. In the end, all the results are summarized and observations, conclusions and recommendations are made regarding the effect of various parameters on ductility of a joint. (author)
Electromagnetic radiation and nonlinear energy flow in an electron beam-plasma system
Whelan, D. A.; Stenzel, R. L.
1985-01-01
It is shown that the unstable electron-plasma waves of a beam-plasma system can generate electromagnetic radiation in a uniform plasma. The generation mechanism is a scattering of the unstable electron plasma waves off ion-acoustic waves, producing electromagnetic waves whose frequency is near the local plasma frequency. The wave vector and frequency matching conditions of the three-wave mode coupling are experimentally verified. The electromagnetic radiation is observed to be polarized with the electric field parallel to the beam direction, and its source region is shown to be localized to the unstable plasma wave region. The frequency spectrum shows negligible intensity near the second harmonic of the plasma frequency. These results suggest that the observed electromagnetic radiation of type III solar bursts may be generated near the local plasma frequency and observed downstream where the wave frequency is near the harmonic of the plasma frequency.
Directory of Open Access Journals (Sweden)
Nelson López
2017-12-01
Full Text Available In this research, the nonlinear behavior of a real-scale experimental joint (node is studied, consisting of three reinforced concrete elements, one column and two beams joined to a structural steel column at the upper level. In the numerical analysis the model of the union was analyzed in the inelastic range, this model was elaborated with the finite element program based on fibers, SeismoStruct to analyze as a function of time, the traction and compression efforts in the confined area and not confined area of the concrete column and in the longitudinal reinforcement steel, as well as verification of the design of the base plate that joins the two columns. The results showed that tensile stresses in the unconfined zone surpassed the concrete breaking point, with cracking occurring just below the lower edge of the beams; in the confined area the traction efforts were much lower, with cracks occurring later than in the non-confined area. The concrete column-steel column joint behaved as a rigid node, so the elastic design was consistent with the calculation methodology of base plates for steel columns.
Directory of Open Access Journals (Sweden)
M.L.Soroka
2012-12-01
Full Text Available Introduction: The implementation of measures for the prevention and spill of dangerous goods is an important aspect of sustainable development of railway transport. oil spills accident are the most dangerous. They are accompanied by significant pollution of all environmental objects. Studying and development of oil localization and clean-up technologies of such accidents is an important problem of environmental protection to modern conditions of railway transport development. The purpose: to improve the effectiveness of traditional methods of oil spill elimination and the development of new clean-up technologies adapted to the real conditions of the railway transport of Ukraine. Methods: To achieve the research purposes was used analysis of material flows, typical for places emergence and localization of the oil spill on the railways. Results: Analysis of standard technological scheme for the oil spills eliminations has shown that the most difficult task of effective clean-up surfaces is the timely delivery of oil sorbents and special equipment to the area spill containment. The general effectiveness of the elimination activities specifies the time from the beginning contact of dangerous goods with environmental objects to the absorption it into the structure of sorbent . Us was developed the technological scheme of oil spill elimination. This scheme provide a permanent and fast access to the sorbents into the oil spill localization area. It was proposed to device that allows you to transport the sorbent into sorption booms directly on the tank for transportation of petroleum products. Conclusions: Preventative accumulation of sorbents to the oil spill elimination into the localization area provides the organizational and operational simplicity of all stages of clean-up technology. Technical and economic assessment shows that the proposed technology is effective, technologically feasible and economically competitive.
Clean-up and matrix effect in LC-MS/MS analysis of food of plant origin for high polar herbicides.
Kaczyński, Piotr
2017-09-01
This study reports an innovative and sensitive procedure for analysis of difficult high polar herbicides (HPH) in diverse foods of plant origin. The QuPPe (Quick Polar Pesticides) method followed by determination by LC-MS/MS was modified. Chromatographic conditions, extraction, clean-up, and matrix effect were studied. Several liquid chromatography stationary and mobile phases were evaluated, and it was found that hydrophilic interaction chromatography (HILIC) gives good retention and sensitivity. An acidified methanol-water mixture was used as an effective extraction solvent of eleven HPH. Dispersive solid-phase clean-up sorbents (C18, GCB, Florisil, chitosan and graphene) were evaluated. The efficiency of the method was examined using data on recovery, precision and matrix effects. High extraction yields were achieved, and recoveries were within the 64-97% range with relative standard deviations <20% for all HPH in all commodities. Low matrix effects were observed when graphene was used during clean-up of onion extract and when chitosan was used for wheat, potato and pea extract. Copyright © 2017 Elsevier Ltd. All rights reserved.
International Nuclear Information System (INIS)
Brown, J.; Cooper, J.R.; Jones, J.A.; Flaws, L.; McGeary, R.; Spooner, J.
1996-10-01
This review examines decontamination and clean-up methodologies that may be applied following an accidental release of radionuclides to the atmosphere in the UK. An accidental release of radionuclides to the environment could cause contamination of land and property, and may necessitate movement of the resident population to reduce their exposure. Decontamination procedures may reduce the level of contamination and, in determining whether to implement such procedures in an affected area, it is necessary to weigh the effectiveness of the techniques against the associated economic costs and other disadvantages. The report gives a review of available methods of decontamination and clean-up in terms of the effectiveness of the various methods to remove activity from building or land surfaces and dose saved. It also considers associated disadvantages, costs, clean-up rates for land and buildings, waste disposal implications, and personnel and resource requirements. On the basis of these factors, the techniques are prioritised and overall strategies for decontamination following releases of both fission products and alpha emitters are presented. (author)
International Nuclear Information System (INIS)
Darroudi, F.; Natarajan, A.T.
1996-01-01
In order to perform retrospective estimations of radiation doses seven years after the nuclear accident in Chernobyl, the frequencies of chromosomal aberrations in the peripheral blood lymphocytes of individuals living in contaminated areas around Chernobyl and the Estonian clean-up workers were determined. The first study group composed of 45 individuals living in four areas (i.e. Rechitsa, Komsomolski, Choiniki and Zaspa) in the vicinity (80-125 km) of Chernobyl and 20 individuals living in Minsk (control group - 340 km from Chernobyl). The second study group (Estonian clean-up workers) composed of 26 individuals involved in cleaning up the Chernobyl for a different period of time (up to 7 months) and a matched control group consisting of 9 probands. Unstable aberrations (dicentrics and rings) were scored in Giemsa stained preparations and stable aberrations (translocations) were analyzed using chromosome specific DNA libraries and fluorescence in situ hybridization (FISH) technique. For both study groups the estimated average dose is between 0,1-0,4 Gy. Among the people living in the contaminated areas in the vicinity of Chernobyl, a higher frequency of numerical aberrations (i.e. trisomy, hyper diploidy) was evident
Energy Technology Data Exchange (ETDEWEB)
Tsysar, S. A., E-mail: sergey@acs366.phys.msu.ru; Nikolaeva, A. V.; Khokhlova, V. A.; Yuldashev, P. V. [Physics Faculty, Moscow State University, Leninskie Gory, Moscow 119991 (Russian Federation); Svet, V. D. [Andreyev Acoustics Institute, 4, Shvernik Street, Moscow 117036 (Russian Federation); Sapozhnikov, O. A. [Physics Faculty, Moscow State University, Leninskie Gory, Moscow 119991 (Russian Federation); Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, 1013 NE 40th Street, Seattle, WA 98105 (United States)
2015-10-28
In the paper the use of receiving and radiating system, which allows to determine the parameters of bone by nonlinear pulse-echo technique and to image of brain structures through the skull bones, was proposed. Accuracy of the skull bone characterization is due to higher measured harmonic and is significantly better than in linear case. In the experimental part focused piezoelectric transducer with diameter 100 mm, focal distance 100 mm, the frequency of 1.092 MHz was used. It was shown that skull bone profiling can be performed with the use of 3rd harmonic since 1st harmonic can be used for visualization of the underlying objects. The use of wideband systems for both skull profiling and brain visualization is restricted by skull attenuation and resulting low effective sensitivity.
International Nuclear Information System (INIS)
Tsysar, S. A.; Nikolaeva, A. V.; Khokhlova, V. A.; Yuldashev, P. V.; Svet, V. D.; Sapozhnikov, O. A.
2015-01-01
In the paper the use of receiving and radiating system, which allows to determine the parameters of bone by nonlinear pulse-echo technique and to image of brain structures through the skull bones, was proposed. Accuracy of the skull bone characterization is due to higher measured harmonic and is significantly better than in linear case. In the experimental part focused piezoelectric transducer with diameter 100 mm, focal distance 100 mm, the frequency of 1.092 MHz was used. It was shown that skull bone profiling can be performed with the use of 3rd harmonic since 1st harmonic can be used for visualization of the underlying objects. The use of wideband systems for both skull profiling and brain visualization is restricted by skull attenuation and resulting low effective sensitivity
Nonlinear thermally induced distortions of a laser beam in a cryogenic disk amplifier
International Nuclear Information System (INIS)
Vyatkin, A G; Khazanov, Efim A
2009-01-01
Taking into account the temperature dependences of the heat conductivity, the refractive index, and the thermal expansion coefficient, we calculated the temperature, elastic stresses, a thermally induced lens and depolarisation of a beam in a cryogenic disk amplifier (an Yb:YAG disk placed between a copper cylinder and a sapphire disk cooled by liquid nitrogen). When the active element (the thickness is 0.6 mm, the orientation is [001], the atomic concentration of Yb is 10%) is pumped by radiation from a diode laser (the beam diameter is 6 mm), the temperature does not exceed 140 K for the heat release power of 100 W. In this case, elastic stresses in the active element are six times lower than the maximum permissible value. The focal distance of the thermally induced lens is 5.5 m and the depolarisation rate is 0.038% per two passes through the active element. Although the heat conductivity of the active element rapidly decreases with temperature, the thermal load can be increased by 1.5-2 times when the dimensions of the active element remain constant. (active media)
Transverse beam dynamics in non-linear Fixed Field Alternating Gradient accelerators
Energy Technology Data Exchange (ETDEWEB)
Haj, Tahar M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States)
2016-03-02
In this paper, we present some aspects of the transverse beam dynamics in Fixed Field Ring Accelerators (FFRA): we start from the basic principles in order to derive the linearized transverse particle equations of motion for FFRA, essentially FFAGs and cyclotrons are considered here. This is a simple extension of a previous work valid for linear lattices that we generalized by including the bending terms to ensure its correctness for FFAG lattice. The space charge term (contribution of the internal coulombian forces of the beam) is contained as well, although it is not discussed here. The emphasis is on the scaling FFAG type: a collaboration work is undertaken in view of better understanding the properties of the 150 MeV scaling FFAG at KURRI in Japan, and progress towards high intensity operation. Some results of the benchmarking work between different codes are presented. Analysis of certain type of field imperfections revealed some interesting features about this machine that explain some of the experimental results and generalize the concept of a scaling FFAG to a non-scaling one for which the tune variations obey a well-defined law.
Kwok, Richard K; McGrath, John A; Lowe, Sarah R; Engel, Lawrence S; Jackson, W Braxton; Curry, Matthew D; Payne, Julianne; Galea, Sandro; Sandler, Dale P
2017-12-01
Adverse mental health effects have been reported following oil spills but few studies have identified specific responsible attributes of the clean-up experience. We aimed to analyse the effects of the 2010 Deepwater Horizon (Gulf of Mexico) disaster on the mental health of individuals involved in oil spill response and clean-up. We used data from the Gulf Long-term Follow-up Study, a cohort of workers and volunteers involved in oil spill clean-up after the Deepwater Horizon disaster. We included 8968 workers (hired after completing training for oil spill response and clean-up) and 2225 non-workers (completed training but were not hired) who completed a Patient Health Questionnaire-8 and four-item Primary Care PTSD Screen to assess for probable depression and post-traumatic stress disorder (PTSD) indicators. Participants were recruited between March 28, 2011, and March 29, 2013. The mental health indicators were assessed at home visits done between May 12, 2011, and May 15, 2013. We used regression models to analyse the effect of potentially stressful job experiences, job type, and total hydrocarbon exposure on mental health indicators. Oil spill response and clean-up work was associated with increased prevalence of depression (prevalence ratio [PR] 1·22, 95% CI 1·08-1·37) and PTSD (PR 1·35, 95% CI 1·07-1·71). Among workers, individuals who reported smelling oil, dispersants, or cleaning chemicals had an elevated prevalence of depression (1·56, 1·37-1·78) and PTSD (2·25, 1·71-2·96). Stopping work because of the heat was also associated with depression (1·37, 1·23-1·53) and PTSD (1·41, 1·15-1·74), as was working as a commercial fisherman before the spill (1·38, 1·21-1·57; and 2·01, 1·58-2·55, respectively). An increase in exposure to total hydrocarbons appeared to be associated with depression and PTSD, but after taking into account oil spill job experiences, only the association between the highest amount of total hydrocarbons and PTSD
Directory of Open Access Journals (Sweden)
Richard K Kwok, PhD
2017-12-01
Full Text Available Summary: Background: Adverse mental health effects have been reported following oil spills but few studies have identified specific responsible attributes of the clean-up experience. We aimed to analyse the effects of the 2010 Deepwater Horizon (Gulf of Mexico disaster on the mental health of individuals involved in oil spill response and clean-up. Methods: We used data from the Gulf Long-term Follow-up Study, a cohort of workers and volunteers involved in oil spill clean-up after the Deepwater Horizon disaster. We included 8968 workers (hired after completing training for oil spill response and clean-up and 2225 non-workers (completed training but were not hired who completed a Patient Health Questionnaire-8 and four-item Primary Care PTSD Screen to assess for probable depression and post-traumatic stress disorder (PTSD indicators. Participants were recruited between March 28, 2011, and March 29, 2013. The mental health indicators were assessed at home visits done between May 12, 2011, and May 15, 2013. We used regression models to analyse the effect of potentially stressful job experiences, job type, and total hydrocarbon exposure on mental health indicators. Findings: Oil spill response and clean-up work was associated with increased prevalence of depression (prevalence ratio [PR] 1Â·22, 95% CI 1Â·08â1Â·37 and PTSD (PR 1Â·35, 95% CI 1Â·07â1Â·71. Among workers, individuals who reported smelling oil, dispersants, or cleaning chemicals had an elevated prevalence of depression (1Â·56, 1Â·37â1Â·78 and PTSD (2Â·25, 1Â·71â2Â·96. Stopping work because of the heat was also associated with depression (1Â·37, 1Â·23â1Â·53 and PTSD (1Â·41, 1Â·15â1Â·74, as was working as a commercial fisherman before the spill (1Â·38, 1Â·21â1Â·57; and 2Â·01, 1Â·58â2Â·55, respectively. An increase in exposure to total hydrocarbons appeared to be associated with depression and PTSD, but
Manning, Robert M.
2012-01-01
The method of moments is used to define and derive expressions for laser beam deflection and beam radius broadening for high-energy propagation through the Earth s atmosphere. These expressions are augmented with the integral invariants of the corresponding nonlinear parabolic equation that describes the electric field of high-energy laser beam to propagation to yield universal equations for the aforementioned quantities; the beam deflection is a linear function of the propagation distance whereas the beam broadening is a quadratic function of distance. The coefficients of these expressions are then derived from a thin screen approximation solution of the nonlinear parabolic equation to give corresponding analytical expressions for a target located outside the Earth s atmospheric layer. These equations, which are graphically presented for a host of propagation scenarios, as well as the thin screen model, are easily amenable to the phase expansions of the wave front for the specification and design of adaptive optics algorithms to correct for the inherent phase aberrations. This work finds application in, for example, the analysis of beamed energy propulsion for space-based vehicles.
Directory of Open Access Journals (Sweden)
Z. Ahmadpoor
2016-02-01
Full Text Available Introduction: There is necessary to clean up the nitrate and phosphate from surface waters before effluence of them to environment and eutrophication formation because of water health importance and considering to nitrate and phosphate consequences. Nitrate and ammonium as the - forms of inorganic and nitrogen have been subjected to the center of issues related to environment pollutants and water resources in a long time. The nitrate is more important than other inorganic nitrogen forms such as ammonium because of various reasons such as high dynamics and causing diseases such as some of digestion system and lymph nodes cancers in adults and methemoglobinemia in infants. Therefore the maximum concentration of this ion in drinking water has been determined as 45 mg.Lit-1 by WHO. Regarding the importance of the water health and the complications due to existence of some compounds such as nitrate and phosphate, in this experiment, the possibility of elimination or decreasing excess nitrate and phosphate from water in hydroponic conditions using of two watercress and pennyroyal plants was evaluated. Watercress(Nasturtiumofficinale and pennyroyal (Menthapulegiumwere selected because of some properties such as adaptability with the most climates of Iranamd less requirements care. Materials and Methods: Two RCD factorial experiments were carried out to evaluate the ability of watercress and pennyroyal to biosorption of nitrate and phosphate from polluted water in hydroponic conditions. First factor was plant species including watercress and pennyroyal. Second factor included nitrate (50, 100, 150 Mg/L and phosphate (5, 10, 15 Mg/L in first and second experiment respectively.The final concentrations of nitrate and phosphate in water was measured using spectrophotometer in wavelength of 410 nm and 690 nm by sulphatebrucine and chloride methods , respectively, which are mentioned in Standard Methods for the Examination of Water and Wastewater. At the end
Directory of Open Access Journals (Sweden)
Chaudhari Virendra Kumar
2017-01-01
Full Text Available This paper deals with the investigation of nonlinear free vibration behavior of elastically supported carbon nanotube reinforced composite (CNTRC beam subjected to thermal loading with random system properties. Material properties of each constituent’s material, volume fraction exponent and foundation parameters are considered as uncorrelated Gaussian random input variables. The beam is supported by a Pasternak foundation with Winkler cubic nonlinearity. The higher order shear deformation theory (HSDT with von-Karman non-linearity is used to formulate the governing equation using Hamilton principle. Convergence and validation study is carried out through the comparison with the available results in the literature for authenticity and accuracy of the present approach used in the analysis. First order perturbation technique (FOPT,Second order perturbation technique (SOPT and Monte Carlo simulation (MCS methods are employed to investigate the effect of geometric configuration, volume fraction exponent, foundation parameters, distribution of reinforcement and thermal loading on nonlinear vibration characteristics CNTRC beam.The present work signifies the accurate analysis of vibrational behaviour influences by different random variables. Results are presented in terms of mean, variance (COV and probability density function (PDF for various aforementioned parameters.
Non-linear temperature-dependent curvature of a phase change composite bimorph beam
Blonder, Greg
2017-06-01
Bimorph films curl in response to temperature. The degree of curvature typically varies in proportion to the difference in thermal expansion of the individual layers, and linearly with temperature. In many applications, such as controlling a thermostat, this gentle linear behavior is acceptable. In other cases, such as opening or closing a valve or latching a deployable column into place, an abrupt motion at a fixed temperature is preferred. To achieve this non-linear motion, we describe the fabrication and performance of a new bilayer structure we call a ‘phase change composite bimorph (PCBM)’. In a PCBM, one layer in the bimorph is a composite containing small inclusions of phase change materials. When the inclusions melt, their large (generally positive and >1%) expansion coefficient induces a strong, reversible step function jump in bimorph curvature. The measured jump amplitude and thermal response is consistent with theory, and can be harnessed by a new class of actuators and sensors.
Nonlinear rolling of a biased ship in a regular beam wave under external and parametric excitations
Energy Technology Data Exchange (ETDEWEB)
El-Bassiouny, A.F. [Mathematics Dept., Benha Univ., Benha (Egypt)
2007-10-15
We consider a nonlinear oscillator simultaneously excited by external and parametric functions. The oscillator has a bias parameter that breaks the symmetry of the motion. The example that we use to illustrate the problem is the rolling oscillation of a biased ship in longitudinal waves, but many mechanical systems display similar features. The analysis took into consideration linear, quadratic, cubic, quintic, and seven terms in the polynomial expansion of the relative roll angle. The damping moment consists of the linear term associated with radiation and viscous damping and a cubic term due to frictional resistance and eddies behind bilge keels and hard bilge corners. Two methods (the averaging and the multiple time scales) are used to investigate the first-order approximate analytical solution. The modulation equations of the amplitudes and phases are obtained. These equations are used to obtain the stationary state. The stability of the proposed solution is determined applying Liapunov's first method. Effects of different parameters on the system behaviour are investigated numerically. Results are presented graphically and discussed. The results obtained by two methods are in excellent agreement. (orig.)
Nonlinear transient responses of beams and rings to impulse loading or fragment impact
International Nuclear Information System (INIS)
Witmer, E.A.; Stagliano, T.R.; Rodal, J.J.A.
1977-01-01
Nuclear power plant protective structures may be subjected to various external missiles such as aircraft and tornado-generated missiles: telephone poles, planks, pipes, rods, automobiles, and other blown vehicles. Also, 'internally-generated missiles' such as fragments from powerplant rotors and aircraft engine rotors may impact protective structures. The present paper is concerned with a very limited part of the cited fragment threat; namely, fragments from high speed rotating machinery such as (1) aircraft engine rotors and (2) stationary power plant turbine rotors. Further, it is assumed that the structures intended to contain or control these fragments consist of initially-isotopic elastic-plastic metals. Certain potential containment/control (C/C) structures behave in a planar (or two-dimensional) fashion while other fragment-attacked C/C structures will undergo general three-dimensional deformations. Predictions for only the former category of fragment-attacked structures are discussed in the present paper. Pertinent experimental data discussed on fragment-attacked structures include (a) steel-sphere impact data involving beam targets and (b) engine rotor fragment impact against a steel containment ring. In all of these cases large-deflection, elastic-plastic transient structural responses occur. (Auth.)
Nonlinear transient responses of beams and rings to impulse loading or fragment impact
International Nuclear Information System (INIS)
Witmer, E.A.; Stagliano, T.R.; Rodal, J.J.A.
1977-01-01
The present paper is concerned with a very limited part of the cited fragment threat; namely, fragments from high speed rotating machinery such as (1) aircraft engine rotors and (2) stationary power plant turbine rotors. Further, it is assumed that the structures intended to contain or control these fragments consist of initially-isotropic elastic-plastic metals. Certain potential containment/control (C/C) structures behave in a planar (or two-dimensional) fashion while other fragment-attacked C/C structures will undergo general three-dimensional deformations. Predictions for only the former category of fragment-attacked structures are discussed in the present paper. Pertinent experimental data discussed here on fragment-attacked structures include (a) steel-sphere impact data involving beam targets and (b) engine rotor fragment impact against a steel containment ring. In all of these cases large-deflection, elastic-plastic transient structural response occur. The governing equations employed are presented in the present analysis to predict the responses of protective (metal) structures to engine-rotor-fragment impact. The protective structure is intended either to contain or to deflect the attacking fragments away from important regions; large-deflection, elasic-plastic structural response is expected because these protective structures must have the least feasible weight. Concise geometric and assumed-displacement-field descriptions of the several types of finite elements to be utilized in subsequent examples are given, together with several categories of strain displacement relations. Both low- and higher-order elements are discussed
Kaminski, Adam
2017-08-22
A method and apparatus to generate harmonically related laser wavelengths includes a pair of lenses at opposing faces of a non-linear optical material. The lenses are configured to promote incoming and outgoing beams to be normal to each outer lens surface over a range of acceptance angles of the incoming laser beam. This reduces reflection loss for higher efficiency operation. Additionally, the lenses allow a wider range of wavelengths for lasers for more universal application. Examples of the lenses include plano-cylindrical and plano-spherical form factors.
International Nuclear Information System (INIS)
2003-01-01
Contaminated and hazardous waste sites, including nuclear facilities, may be subject to clean-up under the U.S. Environmental Protection Agency (EPA). The Comprehensive Environmental Response, Compensation, and Liabilities Act (CERCLA), commonly known as 'Superfund', authorises EPA to respond to releases or threatened releases of hazardous substances, pollutants, or contaminants that may endanger public health or the environment. The legislation defines hazardous substances to include radiation. Entry into Superfund: The EPA may be notified of a site potentially requiring clean up from any source. Potential sites are evaluated under a numerical hazard ranking system, and are then included on the clean-up list ('National Priorities List') if they meet an established threshold. Nuclear Facilities and Radioactively Contaminated Sites under Superfund: Any site may be subject to CERCLA action if EPA determines that it poses a hazard. There are three major types of sites that have been or are subject to action under this program: Federal nuclear facilities, Decommissioned facilities, Privately-owned, unlicensed sites Liabilities Under Superfund: The authorising legislation specifically provided for liability of persons responsible for releases of hazardous waste at uncontrolled sites. Liability under CERCLA is 'strict,' 'retroactive,' and 'joint and several'. Thus, the burden of proof for disproving liability is quite high, and that the extent of the liability is not limited to the share of the waste or hazardous substance contributed by a party. The EPA may pursue liable parties to recover past and future costs associated with clean-up, including direct costs and indirect costs incurred by both EPA and its contractors. Clean-Up Levels: Clean-up goals and technologies are established on a site-specific basis. In general, clean-up goals must meet risk requirements and be consistent with applicable standards. Other factors such as community acceptance, volume reduction
International Nuclear Information System (INIS)
Plotnikov, V.I.; Tuleushev, A.Zh.; Zhabykbaev, G.T.; Kostsov, S.V.; Medvedeva, Z.V.; Plotnikova, O.M.; Chakrova, E.T.; Idrisova, U.R.; Idrisova, D.Zh.
2003-01-01
On the base of laboratory studies and semi-industrial testing the possibility of liquid radioactive wastes clean-up from cesium and cobalt radionuclides in elevated mineralization conditions with help of modified clinoptilolite is shown. In the work the synthesized thin-layer inorganic sorbent (TIS) with conventional name MC-2 (modified clinoptilolite) was used. The Chankanaj deposit's zeolite in the crushed form was base for the TIS production. The copper ferrocyanides serves as the modifier. This sorbent is selective one in relationship to cesium and cobalt radionuclides
Ates, E; Mittendorf, K; Stroka, J; Senyuva, H
2013-01-01
An automated method involving on-line clean-up and analytical separation in a single run using TurboFlow™ reversed phase liquid chromatography coupled to a high resolution mass spectrometer has been developed for the simultaneous determination of deoxynivalenol, T2 toxin, HT2 toxin, zearalenone and fumonisins B1 and B2 in maize, wheat and animal feed. Detection was performed in full scan mode at a resolution of R = 100,000 full width at half maximum with high energy collision cell dissociation for the determination of fragment ions with a mass accuracy below 5 ppm. The extract from homogenised samples, after blending with a 0.1% aqueous mixture of 0.1% formic acid/acetonitrile (43:57) for 45 min, was injected directly onto the TurboFlow™ (TLX) column for automated on-line clean-up followed by analytical separation and accurate mass detection. The TurboFlow™ column enabled specific binding of target mycotoxins, whereas higher molecular weight compounds, like fats, proteins and other interferences with different chemical properties, were removed to waste. Single laboratory method validation was performed by spiking blank materials with mycotoxin standards. The recovery and repeatability was determined by spiking at three concentration levels (50, 100 and 200% of legislative limits) with six replicates. Average recovery, relative standard deviation and intermediate precision values were 71 to 120%, 1 to 19% and 4 to 19%, respectively. The method accuracy was confirmed with certified reference materials and participation in proficiency testing.
International Nuclear Information System (INIS)
Schappell, B; Rucker, G
2007-01-01
An innovative approach to integrate the activities of a decommissioning and deactivation program (D and D) with a soil-groundwater clean up program has had significant positive results saving both money and time at the Department of Energy's Savannah River Site. The accomplishments that have been achieved by the combining the two programs have been remarkable including significant cost savings, economies of scale for sampling and document generation, and alignment of common objectives. Because of the coordination of both activities area-wide ''end states'' can be formulated and be consistent with the customers' cleanup goals and federal regulations. This coordinates and aligns both the environmental clean up and D and D objectives because each must be addressed simultaneously and comprehensively. In this respect, resources from both organizations can be pooled to take advantage of the strengths of each. The new approach allows more efficient use of lean financial resources and optimizes workforce activities to attain the common objectives while being more cost effective, more protective of the environment, and optimizing the use existing resources
Navarro, P; Cortazar, E; Bartolomé, L; Deusto, M; Raposo, J C; Zuloaga, O; Arana, G; Etxebarria, N
2006-09-22
The feasibility of different clean-up procedures was studied for the determination of polycyclic aromatic hydrocarbons (PAHs) in biota samples such as oysters, mussels and fish liver. In this sense, once the samples were extracted--essentially with acetone and in a microwave system--and before they could be analysed by gas chromatography-mass spectrometry (GC-MS), three different approaches were studied for the clean-up step: solid phase extraction (SPE), microwave-assisted saponification (MAS) and gel permeation chromatography (GPC). The main aim of this work was to maximise the recoveries of PAHs and to minimise the presence of interfering compounds in the last extract. In the case of SPE, Florisil cartridges of 1, 2 and 5 g, and silica cartridges of 5 g were studied. In that case, and with oysters and mussels, microwave-assisted extraction and 5 g Florisil cartridges provided good results. In addition, the concentrations obtained for Standard Reference Material (SRM) NIST 2977 (mussel tissue) were in good agreement with the certified values. In the case of microwave-assisted saponification, the extracts were not as clean as those obtained with 5 g Florisil and this fact lead to overestimate the concentration of the heaviest PAHs. Finally, the cleanest extracts were obtained by GPC. The method was successfully applied to mussels, oysters and hake liver, and the results obtained for NIST 2977 (mussel tissue) were within the confidence interval of the certified reference material for most of the certified analytes.
Di Muccio, A; Barbini, D A; Generali, T; Pelosi, P; Ausili, A; Vergori, F; Camoni, I
1997-03-21
Disposable, ready-to-use cartridges filled with macroporous diatomaceous material are used to carry out a partition clean-up that, in a single step, is capable of transferring pesticide residues from aqueous acetone extracts into light petroleum-dichloromethane (75:25, v/v). This procedure takes the place of some functions (such as separatory-funnel partition, drying over anhydrous sodium sulphate and partial adsorption clean-up) usually performed by separate steps in classical schemes. Fourteen pyrethroid pesticides, including tefluthrin, tetramethrin, cyphenothrin, cyfluthrin, flucythrinate, tau-fluvalinate, deltamethrin, bioallethrin, fenpropathrin, lambda-cyhalothrin, permethrin, alpha-cypermethrin, esfenvalerate and tralomethrin were determined using the described procedure with satisfactory recoveries for most of them, at spiking levels ranging from 0.08 to 0.82 mg/kg for the different compounds. Crops subjected to the described procedure included strawberry, apple, and orange gave extracts containing a mass of co-extractives that was between 5 and 30 mg. Compared with classical schemes, the described procedure is simple, less labour intensive, allows parallel handling of several extracts and does not require the preparation and maintenance of equipment. Troublesome emulsions such as those frequently observed in separation funnel partitioning do not occur.
NSGIC Education | GIS Inventory — Oil Fields dataset current as of 1998. Oil and gas production platforms are potential source for oil spills and may interfere with mechanical means to clean up oil...
Maraghechi, Borna; Kolios, Michael C; Tavakkoli, Jahan
2015-01-01
Hyperthermia is a cancer treatment technique that could be delivered as a stand-alone modality or in conjunction with chemotherapy or radiation therapy. Noninvasive and real-time temperature monitoring of the heated tissue improves the efficacy and safety of the treatment. A temperature-sensitive acoustic parameter is required for ultrasound-based thermometry. In this paper the amplitude and the energy of the acoustic harmonics of the ultrasound backscattered signal are proposed as suitable parameters for noninvasive ultrasound thermometry. A commercial high frequency ultrasound imaging system was used to generate and detect acoustic harmonics in tissue-mimicking gel phantoms and ex vivo bovine muscle tissues. The pressure amplitude and the energy content of the backscattered fundamental frequency (p1 and E1), the second (p2 and E2) and the third (p3 and E3) harmonics were detected in pulse-echo mode. Temperature was increased from 26° to 46 °C uniformly through both samples. The amplitude and the energy content of the harmonics and their ratio were measured and analysed as a function of temperature. The average p1, p2 and p3 increased by 69%, 100% and 283%, respectively as the temperature was elevated from 26° to 46 °C in tissue samples. In the same experiment the average E1, E2 and E3 increased by 163%, 281% and 2257%, respectively. A similar trend was observed in tissue-mimicking gel phantoms. The findings suggest that the harmonics generated due to nonlinear ultrasound beam propagation are highly sensitive to temperature and could potentially be used for noninvasive ultrasound tissue thermometry.
International Nuclear Information System (INIS)
Kurkin, S. A.; Koronovski, A. A.; Hramov, A. E.
2009-01-01
Results are presented from a numerical study of the effect of an external magnetic field on the conditions and mechanisms for the formation of a virtual cathode in a relativistic electron beam. Characteristic features of the nonlinear dynamics of an electron beam with a virtual cathode are considered when the external magnetic field is varied. Various mechanisms are investigated by which the virtual cathode oscillations become chaotic and their spectrum becomes a multifrequency spectrum, thereby complicating the dynamics of the vircator system. A general mechanism for chaotization of the oscillations of a virtual cathode in a vircator system is revealed: the electron structures that form in an electron beam interact by means of a common space charge field to give rise to additional internal feedback. That the oscillations of a virtual cathode change from the chaotic to the periodic regime is due to the suppression of the mechanism for forming secondary electron structures.
International Nuclear Information System (INIS)
Teng, L.C.
1980-01-01
In colliding beam storage rings the beam collision regions are generally so short that the beam-beam interaction can be considered as a series of evenly spaced non-linear kicks superimposed on otherwise stable linear oscillations. Most of the numerical studies on computers were carried out in just this manner. But for some reason this model has not been extensively employed in analytical studies. This is perhaps because all analytical work has so far been done by mathematicians pursuing general transcendental features of non-linear mechanics for whom this specific model of the specific system of colliding beams is too parochial and too repugnantly physical. Be that as it may, this model is of direct interest to accelerator physicists and is amenable to (1) further simplification, (2) physical approximation, and (3) solution by analogy to known phenomena
International Nuclear Information System (INIS)
Raman, S.; Dulberg, C.S.; Spasoff, R.A.
1984-08-01
This report describes a historical cohort study of the group of Canadian military personnel exposed to radiation in the 1950s at atomic bomb test blasts in the U.S. and Australia, and at clean-up operations at the Chalk River Nuclear Laboratories. Overall and cause-specific mortality in the exposed group was compared to that of the control cohort of unexposed military personnel, matched on age, service, rank and trade. Analyses indicated no elevation in the exposed cohort, in overall or cause-specific mortality due to diseases associated with radiation. Since this study was restricted to an investigation of mortality, we must stress that we cannot generalize these results or conclusions to current morbidity experienced by the exposed cohort
International Nuclear Information System (INIS)
Orlikovs, G.; Seleznovs, J.; Farbtuha, T.; Straupeniece, I.; Kuzenko, A.; Pokrotnieks, J.
2002-01-01
111 peptic ulcer patients former Chernobyl accident clean-up workers were examined. The patients have been working in the damaged zone during 1986-87 years receiving small radiation dosages. Chronic peptic gastric and duodenal ulcers appeared in them later. The goal of the trial is to investigate the effectiveness of Helicobacter pylori eradication measures in triple-therapy course of medium duration (10 days) include ranitidine, amoxycillinum, and methronidazolum. Upper gastrointestinal endoscopy was accompanied by rapid urease test. The test was repeated after a 1-year period. Analysing the data results we ascertain that the prolonged success of triple-therapy is rather ineffective and have unclear correlation with endoscopic data. This is much evident in case of gastric ulcers. These results testify that clinical course of peptic ulcers in case of post-radiation syndrome differs from the same in population. (authors)
Gallo, Pasquale; Di Marco Pisciottano, Ilaria; Esposito, Francesco; Fasano, Evelina; Scognamiglio, Gelsomina; Mita, Gustavo Damiano; Cirillo, Teresa
2017-04-01
A new method for simultaneous determination of five bisphenols in canned energy drinks by UPLC with fluorescence detection, after clean up on molecularly imprinted polymers, is herein described. The method was validated at two concentration levels, calculating trueness, repeatability and within-laboratory reproducibility, specificity, linearity of detector response, the limits of quantifications and the limits of detection for each bisphenol. The method is specific, reliable and very sensitive, allowing for determination of bisphenol F diglycidyl ether (BFDGE), bisphenol A (BPA), bisphenol B (BPB), bisphenol F (BPF) and bisphenol A diglycidyl ether (BADGE) down to 0.50ng/mL; it was employed to determine contamination levels from these bisphenols in forty energy drinks of different brands, collected from the market in Naples. BPA was detected in 17 out of 40 samples (42.5%); in some energy drinks also BPF, BADGE and BFDGE were determined. Copyright © 2016 Elsevier Ltd. All rights reserved.
International Nuclear Information System (INIS)
French, S.; Haemaelaeinen, R.; Naadland, E.; Roed, J.; Salo, A.; Sinkko, K.
1996-03-01
The EKO 4/c working group of the environmental effects and emergency preparedness programme (EKO) of the Nordic Nuclear Safety Research (NKS) organised a decision conference on August 30th and 31st, 1995 in Stockholm, Sweden. The meeting was designed to be attended by those responsible for planning and deciding on protective actions in the Nordic countries after a nuclear accident. Issues concerning clean-up strategies in an urban environment after a hypothetical and very severe reactor accident were discussed at the meeting. The objectives of the meeting were to provide a shared understanding between the decision makers and the radiation protection community on concerns and issues related to decision on protective actions after a nuclear accident. (6 refs., 2 figs., 3 tabs.)
Energy Technology Data Exchange (ETDEWEB)
French, S. [ed.] [Leeds Univ. (United Kingdom). School of Computer Studies; Finck, R. [ed.] [Swedish Radiation Protection Inst., Stockholm (Sweden); Haemaelaeinen, R. [ed.] [Helsinki Univ. of Technology, Espoo (Finland); Naadland, E. [ed.] [Norwegian Radiation Protection Authority, Oesteraas (Norway); Roed, J. [ed.] [Risoe National Lab., Roskilde (Denmark); Salo, A. [ed.] [Helsinki (Finland); Sinkko, K. [ed.] [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland)
1996-03-01
The EKO 4/c working group of the environmental effects and emergency preparedness programme (EKO) of the Nordic Nuclear Safety Research (NKS) organised a decision conference on August 30th and 31st, 1995 in Stockholm, Sweden. The meeting was designed to be attended by those responsible for planning and deciding on protective actions in the Nordic countries after a nuclear accident. Issues concerning clean-up strategies in an urban environment after a hypothetical and very severe reactor accident were discussed at the meeting. The objectives of the meeting were to provide a shared understanding between the decision makers and the radiation protection community on concerns and issues related to decision on protective actions after a nuclear accident. (6 refs., 2 figs., 3 tabs.).
Helaleh, Murad I H; Al-Rashdan, Amal; Ibtisam, A
2012-05-30
An automated pressurized liquid extraction (PLE) method followed by Power Prep™ clean-up was developed for organochlorinated pesticide (OCP) and polychlorinated biphenyl (PCB) analysis in environmental marine samples of fish, squid, bivalves, shells, octopus and shrimp. OCPs and PCBs were simultaneously determined in a single chromatographic run using gas chromatography-mass spectrometry-negative chemical ionization (GC-MS-NCI). About 5 g of each biological marine sample was mixed with anhydrous sodium sulphate and placed in the extraction cell of the PLE system. PLE is controlled by means of a PC using DMS 6000 software. Purification of the extract was accomplished using automated Power Prep™ clean-up with a pre-packed disposable silica column (6 g) supplied by Fluid Management Systems (FMS). All OCPs and PCBs were eluted from the silica column using two types of solvent: 80 mL of hexane and a 50 mL mixture of hexane and dichloromethane (1:1). A wide variety of fish and shellfish were collected from the fish market and analyzed using this method. The total PCB concentrations were 2.53, 0.25, 0.24, 0.24, 0.17 and 1.38 ng g(-1) (w/w) for fish, squid, bivalves, shells, octopus and shrimp, respectively, and the corresponding total OCP concentrations were 30.47, 2.86, 0.92, 10.72, 5.13 and 18.39 ng g(-1) (w/w). Lipids were removed using an SX-3 Bio-Beads gel permeation chromatography (GPC) column. Analytical criteria such as recovery, reproducibility and repeatability were evaluated through a range of biological matrices. Copyright © 2012 Elsevier B.V. All rights reserved.
Míguez-Framil, Martha; Moreda-Piñeiro, Antonio; Bermejo-Barrera, Pilar; Alvarez-Freire, Iván; Tabernero, María Jesús; Bermejo, Ana María
2010-10-08
A simple and fast sample pre-treatment method based on matrix solid-phase dispersion (MSPD) for isolating cocaine, benzoylecgonine (BZE), codeine, morphine and 6-monoacethylmorphine (6-MAM) from human hair has been developed. The MSPD approach consisted of using alumina (1.80 g) as a dispersing agent and 0.6M hydrochloric acid (4 mL) as an extracting solvent. For a fixed hair sample mass of 0.050 g, the alumina mass to sample mass ratio obtained was 36. A previously conditioned Oasis HLB cartridge (2 mL methanol, plus 2 mL ultrapure water, plus 1 mL of 0.2M/0.2M sodium hydroxide/boric acid buffer solution at pH 9.2) was attached to the end of the MSPD syringe for on column clean-up of the hydrochloric acid extract and for transferring the target compounds to a suitable solvent for gas chromatography (GC) analysis. Therefore, the adsorbed analytes were directly eluted from the Oasis HLB cartridges with 2 mL of 2% acetic acid in methanol before concentration by N(2) stream evaporation and dry extract derivatization with N-methyl-tert-butylsilyltrifluoroacetamide (BSTFA) and chlorotrimethylsilane (TMCS). The optimization/evaluation of all the factors affecting the MSPD and on column clean-up procedures has led to a fast sample treatment, and analytes extraction and pre-concentration can be finished in approximately 30 min. The developed method has been applied to eight hair samples from poli-drug abusers and measured analyte concentrations have been found to be statistically similar (95% confidence interval) to those obtained after a conventional enzymatic hydrolysis method (Pronase E). Copyright © 2010. Published by Elsevier B.V.
International Nuclear Information System (INIS)
Sun Feng; Pan Rong
2014-01-01
According to a large-span half-steel-concrete (HSC) composited beam in the composited roof in the HTR-PM, a 1:3 scale specimen is investigated by the static load test. By analyzing the loading, deflection, strain and fracture development of the specimen in the process, studying the mechanical characteristics and failure pattern of such components. The ANSYS finite element software is utilized in this paper to analyze the nonlinearity behavior of the HSC beam specimen, and through comparing the experimental results and the numerical simulation, it can be illustrated that the finite element model can simulate the HSC beam accurately. From the test results, it can be concluded that by means of appropriate shear connection and anchorage length, steel plate and concrete can work together very well and the HSC beam has good load carrying capacity and ductility. These conclusions can serve as a preliminary design reference for the large span half-steel-concrete composite beam in NPP. (author)
International Nuclear Information System (INIS)
Gao Yitian; Tian Bo
2003-01-01
A variable-coefficient unstable nonlinear Schroedinger model is hereby investigated, which arises in such applications as the electron-beam plasma waves and Rayleigh-Taylor instability in nonuniform plasmas. With computerized symbolic computation, families of exact analytic dark- and bright-soliton-like solutions are found, of which some previously published solutions turn out to be the special cases. Similarity solutions also come out, which are expressible in terms of the elliptic functions and the second Painleve transcendent. Some observable effects caused by the variable coefficient are predicted, which may be detected in the future with the relevant space or laboratory plasma experiments with nonuniform background existing
International Nuclear Information System (INIS)
Maximov, A.V.; Ourdev, I.G.; Rozmus, W.; Capjack, C.E.; Mounaix, Ph.; Huller, S.; Pesme, D.; Tikhonchuk, V.T.; Divol, L.
2000-01-01
It is shown that plasma-induced angular spreading and spectral broadening of a spatially incoherent laser beam correspond to increased spatial and temporal incoherence of the laser light. The spatial incoherence is characterized by an effective beam f-number, decreasing in space along the direction of light propagation. Plasma-induced beam smoothing can influence laser-plasma interaction physics. In particular, decreasing the correlation time of the propagating laser light may dramatically reduce the levels of backward stimulated Brillouin and Raman scattering inside the plasma. Also, the decrease of the laser beam effective f-number reduces the reflectivity of backward stimulated Brillouin scattering. (authors)
Nonlinear dynamics aspects of particle accelerators
International Nuclear Information System (INIS)
Araki, H.; Ehlers, J.; Hepp, K.; Kippenhahn, R.; Weidenmuller, A.; Zittartz, J.
1986-01-01
This book contains 18 selections. Some of the titles are: Integrable and Nonintegrable Hamiltonian Systems; Nonlinear Dynamics Aspects of Modern Storage Rings; Nonlinear Beam-Beam Resonances; Synchro-Betatron Resonances; Review of Beam-Beam Simulations; and Perturbation Method in Nonlinear Dynamics
Walker, R.J.
1988-06-16
A method of cleaning an exhaust gas containing particulates, SO/sub 2/ and NO/sub x/ is described. The method involves prescrubbing with water to remove HCl and most of the particulates, scrubbing with an aqueous absorbent containing a metal chelate and dissolved sulfite salt to remove NO/sub x/ and SO/sub 2/, and regenerating the absorbent solution by controlled heating, electrodialysis and carbonate salt addition. The NO/sub x/ is removed as N/sub 2/ gas or nitrogen sulfonate ions and the oxides of sulfur are removed as a valuable sulfate salt. 4 figs.
Dynamical chaos and beam-beam models
International Nuclear Information System (INIS)
Izrailev, F.M.
1990-01-01
Some aspects of the nonlinear dynamics of beam-beam interaction for simple one-dimensional and two-dimensional models of round and flat beams are discussed. The main attention is paid to the stochasticity threshold due to the overlapping of nonlinear resonances. The peculiarities of a round beam are investigated in view of using the round beams in storage rings to get high luminosity. 16 refs.; 7 figs
Nonlinear dynamics in Nuclotron
International Nuclear Information System (INIS)
Dinev, D.
1997-01-01
The paper represents an extensive study of the nonlinear beam dynamics in the Nuclotron. Chromatic effects, including the dependence of the betatron tunes on the amplitude, and chromatic perturbations have been investigated taking into account the measured field imperfections. Beam distortion, smear, dynamic aperture and nonlinear acceptance have been calculated for different particle energies and betatron tunes
Mariussen, Espen; Haukås, Marianne; Arp, Hans Peter H; Goss, Kai-Uwe; Borgen, Anders; Sandanger, Torkjel M
2010-02-26
To optimize clean-up procedures for the analysis of alpha-, beta-, and gamma-hexabromocyclododecanes (HBCD) in environmental and biological extracts, their retention behavior on silica gel and florisil was investigated using diverse mobile-phase solvents and accounting for matrix effects. The beta-diastereomer, relative to the alpha- and gamma-diastereomers, is substantially retained on both florisil and silica gel regardless of the solvent used. The beta-diastereomer is therefore prone to undergo selective loss during clean-up. This sequence is counterintuitive to sequences based on reverse-phase chromatography with a C18-column, in which the alpha- (and not the beta-) isomer is eluted first when using a polar solvent. There has been some discrepancy regarding the structures of these diastereomers in the literature, with structures based on X-ray crystallography only becoming recently available. Based on these X-ray crystal structures, physical-chemical properties (the octanol-water partitioning constant, the Henry's law constant, subcooled liquid vapour pressures and subcooled liquid water solubilities) of the HBCD diastereomers were estimated using the quantum-chemistry based software COSMOtherm, and were found to differ from previously calculated values using different structures (e.g. log K(aw) for alpha-, beta-, and gamma-HBCD are here estimated to be -8.3, -9.3 and -8.2 respectively). Hypothesis relating differences in structure to physical-chemical properties and retention sequences are presented. The extra retention of the beta-diastereomer on silica gel and florisil is likely because it can form both greater specific (i.e. polar) and non-specific (i.e. non-polar) interactions with surfaces than the other diastereomers. Non-specific interactions can also account for the counter-intuitive elution orders with C(18)-reverse-phase chromatography. These results indicate that care should be taken when isolating HBCDs and other molecular diastereomers from
International Nuclear Information System (INIS)
Wu Jun; Lin Youjian; Lu Jian; Wilson, Chris
2011-01-01
A rapid ultrasonic extraction method coupled with a heated-copper clean-up procedure for removing interfering constituents was developed for analyzing pyrethroid and phenylpyrazole pesticides in sediments. Incubation of the 60 mL extract with 12 g copper granules at 60 o C for 2 h was determined to be the optimal conditions for removing the interfering constituents. Eleven pyrethroid and phenylpyrazole pesticides were spiked into sediment samples to determine the effectiveness of the ultrasonic extraction method. The average recoveries of pyrethroids and phenylpyrazoles in sediment at 4 o C storage on day 0, 1, 7, 14, and 21 ranged from 98.6 to 120.0%, 79.2 to 116.0%, 85.0 to 119.7%, 93.6 to 118.7%, and 92.1 to 118.2%, respectively, with all percent relative standard deviations less than 10% (most o C. Recoveries of the pesticides ranged from 98.6% to 120.0% for lowest fortification level (2-16 μg kg -1 ), from 97.8% to 117.9% for middle fortification level (10-80 μg kg -1 ), and from 94.3% to 118.1% for highest fortification level (20-160 μg kg -1 ). Relative standard deviations of pesticide recoveries were usually less than 7%. Method detection limits of target pesticides ranged from 0.22 μg kg -1 to 3.72 μg kg -1 . Furthermore, field sediment samples collected from four residential lakes during a three-month monitoring period were analyzed to evaluate the effectiveness of this method. Bifenthrin was detected in all of sediment samples (highest concentration 260.33 ± 41.71 μg kg -1 , lowest concentration 5.68 ± 0.38 μg kg -1 ), and fipronil sulfone was detected at least once in sediment samples collected from three sites with concentrations ranging from 1.73 ± 0.53 to 7.53 ± 0.01 μg kg -1 . - Highlights: → A rapid extraction and copper-based clean-up method was developed. → Recoveries after storage at 4 o C for 21 d ranged from 79.2 to 120.0%. → Percent relative standard deviations less than 10% (most -1 to 3.72 μg kg -1 .
Energy Technology Data Exchange (ETDEWEB)
Ha, Dang Thi; Tuan, Mai Anh; Viet, Nguyen Quoc; Sanh, Nguyen Thi [Vietnamese Academy of Science and Technology (VAST) (Viet Nam). Inst. of Biotechnology; Sau, Trinh Khac [Vietnam-Russian Tropical Center (Viet Nam); Papke, O. [ERGO Forschungsgesellschaft, Hamburg (Germany)
2004-09-15
There are many microbes that can degrade polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurants (PCDFs) and polychlorinated biphenyls (PCBs) have been isolated including purified bacteria, actinomycetes, white rods, filamentous fungi, anaerobes and also anaerobic and aerobic consortia. Bioremediation one of biological remediation has been studied as hopeful alternative to physical and chemical treatments that using for cleaning up PCDDs, PCDFs. In Vietnam for cleaning up ''hot spot'' of some former military air bases, bioremediation has been studying in different scales of Danang site. After 18 to 24 month treatments, the reduction of toxicity was significally detected. In order to study biodegradability by different groups and one of dominated strain that are existing microorganisms in our treatments, the investigation of 2,3,7,8 TCDD anaerobic and aerobic degradations was carried out in the laboratory condition. Anaerobic microbial consortium containing three different bacteria such as two Gram- negative vibrio and rod and one gram positive cocoides bacteria. This consortium could degrade 118 pg TEQ/ml 2,3,7,8 TCDD after 133 days under sulfate reduction. Concentration of 2,3,7,8 TCDD in the soil extract that adding to medium at starting point of cultivation was 144.6 pg TEQ/ml. About 81% toxicity was removed. Aerobic consortium containing all three Gram-negative bacteria and one fungal strain. After 9 day shaking at 180 rpm/min and 30 C, 85.6 % of 164.45 pg TEQ/ml 2,3,7,8 TCDD was removed. Other preliminary results of study of 2,3,7,8 TCDD biodegradation as sole carbon and energy by show that this strain FDN30 could remove 43,45 pg TEQ/ml (59%) of 73,1 pgTEQ/ml adding dioxin after two weeks. These findings explain why high concentration of contaminants in treated soil was decreased after two year treatment. Indigenous microorganisms play leading role in the detoxification of 2,3,7,8 TCDD in contaminated soils.
Salgueiro-González, N; Turnes-Carou, I; Muniategui-Lorenzo, S; López-Mahía, P; Prada-Rodríguez, D
2014-12-10
A less time-, solvent- and sorbent-consuming analytical methodology for the determination of bisphenol A and alkylphenols (4-tert-octylphenol, 4-octylphenol, 4-n-nonylphenol, nonylphenol) in marine sediment was developed and validated. The method was based on selective pressurized liquid extraction (SPLE) with a simultaneous in cell clean up combined with liquid chromatography-electrospray ionization tandem mass spectrometry in negative mode (LC-ESI-MS/MS). The SPLE extraction conditions were optimized by a Plackett-Burman design followed by a central composite design. Quantitation was performed by standard addition curves in order to correct matrix effects. The analytical features of the method were satisfactory: relative recoveries varied between 94 and 100% and repeatability and intermediate precision were <6% for all compounds. Uncertainty assessment of measurement was estimated on the basis of an in-house validation according to EURACHEM/CITAC guide. Quantitation limits of the method (MQL) ranged between 0.17 (4-n-nonylphenol) and 4.01 ng g(-1) dry weight (nonylphenol). Sensitivity, selectivity, automaticity and fastness are the main advantages of this green methodology. As an application, marine sediment samples from Galicia coast (NW of Spain) were analysed. Nonylphenol and 4-tert-octylphenol were measured in all samples at concentrations between 20.1 and 1409 ng g(-1) dry weight, respectively. Sediment toxicity was estimated and no risk to aquatic biota was found. Copyright © 2014 Elsevier B.V. All rights reserved.
Cao, Jiliang; Kong, Weijun; Zhou, Shujun; Yin, Lihui; Wan, Li; Yang, Meihua
2013-04-01
A simple, reliable, and low-cost method based on molecularly imprinted polymer as a selective sorbent of SPE was proposed for the determination of ochratoxin A (OTA) in beer, red wine, and grape juice by HPLC coupled with fluorescence detection (HPLC-FLD). Samples were diluted with water and cleaned up with an AFFINIMIP® SPE OTA column. After washing and eluting, the analyte was analyzed by HPLC-FLD. Under the optimized conditions, LOD and LOQ for OTA were 0.025 and 0.08 ng/mL, respectively. The recoveries of OTA from beer, red wine, and grape spiked at 0.1, 2, and 5 ng/mL ranged from 91.6 to 101.7%. Furthermore, after a simple regenerated procedure, the molecularly imprinted polymer based SPE column could be reused at least 14 times to achieve more than 80% recoveries of OTA in real samples. The developed method was applied to the detection of 30 beer, red wine, and grape juice samples and only four samples were contaminated by OTA with levels below the legal limits. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Zougagh, Mohammed; Ríos, Angel
2008-08-01
An automatic method for the separation and determination of riboflavin (RF) vitamins (RF, flavin mononucleotide and flavin adenine dinucleotide) in food samples (chicken liver, tablet and powder milk) is proposed. The method is based on the on-line coupling of a supercritical fluid extractor (SFE) with a continuous flow-CE system with guided optical fiber fluorimetric detection (CF-CE-FD). The whole SFE-CF-CE-FD arrangement allowed the automatic treatment of food samples (clean-up of the sample followed by the extraction of the analytes), and the direct introduction of a small volume of the extracted plug to the CE-FD system for the determination of RF vitamins. Fluorescence detection introduced an appropriated sensitivity and contributed to avoid interferences of nonfluorescent polar compounds coming from the matrix samples in the extracted plug. Electrophoretic responses were linear within the 0.05-1 microg/g range, whereas the detection limits of RF vitamins were in the 0.036-0.042 microg/g range. The proposed arrangement opens up interesting prospects for the direct determination of polar analytes in complex samples with a good throughput and high level of automation.
Lorenzo, María; Campo, Julián; Picó, Yolanda
2018-03-22
A solid-liquid extraction method in combination with high-performance liquid chromatography and tandem mass spectrometry was developed and optimized for extraction and analysis of organophosphorus flame retardants in soil and fish. Methanol was chosen as the optimum extraction solvent, not only in terms of extraction efficiency, but also for its broader analyte coverage. The subsequent clean-up by solid-phase extraction is required to eliminate matrix coextractives and reduce matrix effects. Recoveries of the optimized method were 50-121% for soil and 47-123% for biota, both with high precision (RSDs solid-phase extraction cartridge clogging that increase variability and analysis time. The method was successfully applied for the determination of organophosphorus flame retardants in soil and fish from L'Albufera Natural Park (Valencia, Spain). Target compounds were detected in all soil and fish samples with values varying from 13.8 to 89.7 ng/g dry weight and from 3.3 to 53.0 ng/g wet weight, respectively. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Oakley, Jennifer A; Shaw, Kirsty J; Docker, Peter T; Dyer, Charlotte E; Greenman, John; Greenway, Gillian M; Haswell, Stephen J
2009-06-07
A silica monolith used to support both electro-osmotic pumping (EOP) and the extraction/elution of DNA coupled with gel-supported reagents is described. The benefits of the combined EOP extraction/elution system were illustrated by combining DNA extraction and gene amplification using the polymerase chain reaction (PCR) process. All the reagents necessary for both processes were supported within pre-loaded gels that allow the reagents to be stored at 4 degrees C for up to four weeks in the microfluidic device. When carrying out an analysis the crude sample only needed to be hydrodynamically introduced into the device which was connected to an external computer controlled power supply via platinum wire electrodes. DNA was extracted with 65% efficiency after loading lysed cells onto a silica monolith. Ethanol contained within an agarose gel matrix was then used to wash unwanted debris away from the sample by EOP (100 V cm(-1) for 5 min). The retained DNA was subsequently eluted from the monolith by water contained in a second agarose gel, again by EOP using an electric field of 100 V cm(-1) for 5 min, and transferred into the PCR reagent containing gel. The eluted DNA in solution was successfully amplified by PCR, confirming that the concept of a complete self-contained microfluidic device could be realised for DNA sample clean up and amplification, using a simple pumping and on-chip reagent storage methodology.
Liu, Rentao; Jiang, Jiping; Guo, Liang; Shi, Bin; Liu, Jie; Du, Zhaolin; Wang, Peng
2016-06-01
In-depth filtering of emergency disposal technology (EDT) and materials has been required in the process of environmental pollution emergency disposal. However, an urgent problem that must be solved is how to quickly and accurately select the most appropriate materials for treating a pollution event from the existing spill control and clean-up materials (SCCM). To meet this need, the following objectives were addressed in this study. First, the material base and a case base for environment pollution emergency disposal were established to build a foundation and provide material for SCCM screening. Second, the multiple case-based reasoning model method with a difference-driven revision strategy (DDRS-MCBR) was applied to improve the original dual case-based reasoning model method system, and screening and decision-making was performed for SCCM using this model. Third, an actual environmental pollution accident from 2012 was used as a case study to verify the material base, case base, and screening model. The results demonstrated that the DDRS-MCBR method was fast, efficient, and practical. The DDRS-MCBR method changes the passive situation in which the choice of SCCM screening depends only on the subjective experience of the decision maker and offers a new approach to screening SCCM.
International Nuclear Information System (INIS)
Moore, B.
1996-01-01
This issue of the project newsletter described the nature of bioventing, air sparging and wetland remediation. It reviewed their effectiveness in remediating hydrocarbon contaminated soil above the groundwater surface. Bioventing was described as an effective, low cost treatment in which air is pumped below ground to stimulate indigenous bacteria. The bacteria then use the oxygen to consume the hydrocarbons, converting them to CO 2 and water. Air sparging involves the injection of air below the groundwater surface. As the air rises, hydrocarbons are stripped from the contaminated soil and water. The advantage of air sparging is that it cleans contaminated soil and water from below the groundwater surface. Hydrocarbon contamination of wetlands was described as fairly common. Conventional remediation methods of excavation, trenching, and bellholes to remove contamination often cause extreme harm to the ecosystem. Recent experimental evidence suggests that wetlands may be capable of attenuating contaminated water through natural processes. Four hydrocarbon contaminated wetlands in Alberta are currently under study. Results to date show that peat's high organic content promotes sorption and biodegradation and that some crude oil spills can been resolved by natural processes. It was suggested that assuming peat is present, a good clean-up approach may be to contain the contaminant source, monitor the lateral and vertical extent of contamination, and wait for natural processes to resolve the problem. 3 figs
International Nuclear Information System (INIS)
Sushko, V.O.; Shvajko, L.Yi.; Bazika, K.D.; Ryazhs'ka, A.S.
2015-01-01
Studied 60 chronic obstructive pulmonary disease (COPD) patients before treatment and 1 year after from the beginning, who were randomly assigned to two groups: the first group of patients (32 persons) additionally was appointed long reception (6 months) combination Ambroxol (30 mg x 3 times per day) and Essenciale (600 mg x 3 times per day), in the second group (28 people) patients received only basic therapy. The doses of radiation exposure were 25-500 mSv. Were studied clinical, functional characteristics, the number of exacerbations. Low response to the basic COPD therapy were shown by clean-up workers of the Chornobyl NPP accident, which is defined by the absence of significant changes in lung function tests. Additional appointments to the basic treatment of COPD combination of Ambroxol (30 mg x 3 times per day) and Essenciale (600 mg x 3 times per day) within 6 months of the liquidators of the Chernobyl made it possible to reduce the frequency of exacerbations in 46.9% patients without significant improvement in lung function tests
Energy Technology Data Exchange (ETDEWEB)
Berg, M.T.; Reed, B.E.; Gabr, M.
1993-07-01
West Virginia University (WVU) and the US DOE Morgantown Energy Technology Center (METC) entered into a Cooperative Agreement on August 29, 1992 entitled ``Decontamination Systems Information and Research Programs.`` Stipulated within the Agreement is the requirement that WVU submit to METC a series of Technical Progress Report for Year 1 of the Agreement. This report reflects the progress and/or efforts performed on the following nine technical projects encompassed by the Year 1 Agreement for the period of April 1 through June 30, 1993: Systematic assessment of the state of hazardous waste clean-up technologies; site remediation technologies -- drain-enhanced soil flushing (DESF) for organic contaminants removal; site remediation technologies -- in situ bioremediation of organic contaminants; excavation systems for hazardous waste sites; chemical destruction of polychlorinated biphenyls; development of organic sensors -- monolayer and multilayer self-assembled films for chemical sensors; Winfield lock and dam remediation; Assessments of Technologies for hazardous waste site remediation -- non-treatment technologies and pilot scale test facility implementation; and remediation of hazardous sites with stream reforming.
National Research Council Canada - National Science Library
McGraw, Robert J
2006-01-01
.... The recorded data, specifically for homogeneous beams of 7075 aluminum, have been referenced as a baseline for the past thirty years to validate numerous computer models and theories in an effort...
Energy Technology Data Exchange (ETDEWEB)
Wu Jun; Lin Youjian; Lu Jian; Wilson, Chris, E-mail: pcwilson@ufl.edu
2011-08-15
A rapid ultrasonic extraction method coupled with a heated-copper clean-up procedure for removing interfering constituents was developed for analyzing pyrethroid and phenylpyrazole pesticides in sediments. Incubation of the 60 mL extract with 12 g copper granules at 60 {sup o}C for 2 h was determined to be the optimal conditions for removing the interfering constituents. Eleven pyrethroid and phenylpyrazole pesticides were spiked into sediment samples to determine the effectiveness of the ultrasonic extraction method. The average recoveries of pyrethroids and phenylpyrazoles in sediment at 4 {sup o}C storage on day 0, 1, 7, 14, and 21 ranged from 98.6 to 120.0%, 79.2 to 116.0%, 85.0 to 119.7%, 93.6 to 118.7%, and 92.1 to 118.2%, respectively, with all percent relative standard deviations less than 10% (most < 6%). This illustrated the stability of pyrethroids and phenylpyrazoles in sediment during sediment aging at 4 {sup o}C. Recoveries of the pesticides ranged from 98.6% to 120.0% for lowest fortification level (2-16 {mu}g kg{sup -1}), from 97.8% to 117.9% for middle fortification level (10-80 {mu}g kg{sup -1}), and from 94.3% to 118.1% for highest fortification level (20-160 {mu}g kg{sup -1}). Relative standard deviations of pesticide recoveries were usually less than 7%. Method detection limits of target pesticides ranged from 0.22 {mu}g kg{sup -1} to 3.72 {mu}g kg{sup -1}. Furthermore, field sediment samples collected from four residential lakes during a three-month monitoring period were analyzed to evaluate the effectiveness of this method. Bifenthrin was detected in all of sediment samples (highest concentration 260.33 {+-} 41.71 {mu}g kg{sup -1}, lowest concentration 5.68 {+-} 0.38 {mu}g kg{sup -1}), and fipronil sulfone was detected at least once in sediment samples collected from three sites with concentrations ranging from 1.73 {+-} 0.53 to 7.53 {+-} 0.01 {mu}g kg{sup -1}. - Highlights: {yields} A rapid extraction and copper-based clean-up method was
International Nuclear Information System (INIS)
Agnew, K.; Purdie, P.; Agnew, K.; Cundy, A.B.; Hopkinson, L.; Croudace, I.W.; Warwick, P.E.F.
2009-01-01
This paper details the development (and implementation) of a novel, low-cost electrokinetic soil clean-up method for treatment of Pu-labelled soil wastes at the AWE Aldermaston site, Berkshire, U.K. Nuclear weapons manufacture and maintenance, and related research and development activities, have been carried out at the Aldermaston site for over 50 years, and these historical operations have generated a number of contaminated land legacy issues, including soils which contain above background (although radiologically insignificant) specific activities of Pu. Much of the Pu-labelled soil has been removed (via soil excavation), and is held in containment units on site, prior to remediation / decommissioning. Based on initial small-scale laboratory trials examining the potential for Pu removal and directed migration under a low intensity electrical field, a two year project (funded by the former UK Department of Trade and Industry and AWE PLC) has been implemented, and is reported here, involving a focussed programme of laboratory trials followed by a full-scale field trial to examine the potential of low-cost electrokinetic techniques to reduce the activity of Pu in clay-rich site soils, and reduce site waste disposal costs. Pu (and U) exhibited relatively complex behaviour in the laboratory trials, with Pu forming mobile soluble oxy-anionic species under the high pHs generated by the electrokinetic treatment technique. Clear mobilisation of Pu and U (along with a range of other elements) was however observed, in a range of soil types. The relative efficiency of remobilization was element-dependant, and, in terms of heavy metal contaminants, radionuclides, and the stable analogues of radionuclides known to be problematic at other nuclear sites, was (from most to least mobile) Cl > Zn > Sr > U > Pu > Pb. Both Pu and U showed enhanced mobility when the low-cost soil conditioning agent citric acid was added prior to electrokinetic treatment. Full-scale field trials of
International Nuclear Information System (INIS)
Scroggins, R.; Princz, J.; Moody, M.; Olsgard-Dumanski, M.; Haderlein, L.; Moore, B.
2010-01-01
This presentation reported on a multi-year research project in which a broad range of boreal forest test methods for assessing petroleum hydrocarbon (PHC) toxicity in contaminated soil were used to show that clean-up decisions can be made on a field-wide basis through focused biological testing of typical drill sump and flare pit locations within an oil and gas field. Remediation at most sites will likely be limited to the Alberta soil eco-contact guidelines for PHC F2 and F3 fractions. Since Tier 1 eco-contact guidelines are derived using toxicity data from fresh crude and using agricultural plant species, it was more logical to follow a Tier 2 eco-contact pathway approach because most contamination was related to drilling sumps and flare pits containing highly weathered PHCs and species native to the boreal eco-zone of Canada. The site-specific remedial objective (SSRO) option within the Tier 2 guideline was used because of the large number of sites requiring remediation, and the similarity of sites within pre-determined Risk Assessment Zones. For representative contaminated soils, a SSRO was derived from the twenty-fifth percentile of the estimated species sensitivity distribution of all acceptable boreal plant, earthworm, springtail and mite test endpoints. The purpose of the project was to reduce soil volumes sent to landfill during site remediation by showing that residual impacts from weathered PHC in soil do not have damaging effects on boreal forest receptors following remediation. Data was included to show the value of this approach and the variability between sites and their effect on regionalizing a Tier 2 eco-contact guideline.
Energy Technology Data Exchange (ETDEWEB)
Scroggins, R.; Princz, J. [Environment Canada, Ottawa, ON (Canada); Moody, M. [Saskatchewan Research Council, Regina, SK (Canada); Olsgard-Dumanski, M.; Haderlein, L. [WorleyParsons Canada, Calgary, AB (Canada); Moore, B. [Devon Canada Corp., Calgary, AB (Canada)
2010-07-01
This presentation reported on a multi-year research project in which a broad range of boreal forest test methods for assessing petroleum hydrocarbon (PHC) toxicity in contaminated soil were used to show that clean-up decisions can be made on a field-wide basis through focused biological testing of typical drill sump and flare pit locations within an oil and gas field. Remediation at most sites will likely be limited to the Alberta soil eco-contact guidelines for PHC F2 and F3 fractions. Since Tier 1 eco-contact guidelines are derived using toxicity data from fresh crude and using agricultural plant species, it was more logical to follow a Tier 2 eco-contact pathway approach because most contamination was related to drilling sumps and flare pits containing highly weathered PHCs and species native to the boreal eco-zone of Canada. The site-specific remedial objective (SSRO) option within the Tier 2 guideline was used because of the large number of sites requiring remediation, and the similarity of sites within pre-determined Risk Assessment Zones. For representative contaminated soils, a SSRO was derived from the twenty-fifth percentile of the estimated species sensitivity distribution of all acceptable boreal plant, earthworm, springtail and mite test endpoints. The purpose of the project was to reduce soil volumes sent to landfill during site remediation by showing that residual impacts from weathered PHC in soil do not have damaging effects on boreal forest receptors following remediation. Data was included to show the value of this approach and the variability between sites and their effect on regionalizing a Tier 2 eco-contact guideline.
Preuss, Ralf; Angerer, Jürgen
2004-03-05
We developed a new 3-D HPLC method for on-line clean-up and simultaneous quantification of two important naphthalene metabolites, 1-naphthol and 2-naphthol, in human urine. Except an enzymatic hydrolysis no further sample pre-treatment is necessary. The metabolites are stripped from urinary matrix by on-line extraction on a restricted access material pre-column (RAM RP-8), transferred in backflush mode onto a silica-based CN-(cyano)phase column for further purification from interfering substances. By another successive column switching step both analytes are transferred with a minimum of overlapping interferences onto a C12 bonded reversed phase column with trimethylsilyl endcapping where the final separation is carried out. The entire arrangement is software controlled. Eluting analytes are quantified by fluorescence detection (227/430 nm) after an external calibration. Within a total run time of 40 min we can selectively quantify both naphthols with detection limits in the lower ppb range (1.5 and 0.5 microg/l for 1- and 2-naphthol, respectively) with excellent reliability (ensured by precision, accuracy, matrix-independency and FIOH quality assurance program participation). First results on a collective of 53 occupationally non exposed subjects showed mean levels of 11.0 microg/l (1-naphthol) and 12.9 microg/l (2-naphthol). Among smokers (n=21) a significantly elevated mean level of urinary naphthols was determined (1-naphthol: 19.2 microg/l and 2-naphthol: 23.7 microg/l) in comparison to non smokers (n=32; 1-naphthol: 5.6 microg/l, 2-naphthol: 5.6 microg/l).
Wang, Yaling; Chai, Tongjie; Lu, Guozhong; Quan, Chunsan; Duan, Huiyong; Yao, Meiling; Zucker, Bert-Andree; Schlenker, Gerd
2008-06-01
An AOZ method, based on high-performance liquid chromatography (HPLC), was optimized on HPLC condition such as mobile phase and wavelength to simultaneously quantify six kinds of mycotoxins [four aflatoxins (AFs), ochratoxin A (OTA) and zearalenone (ZEA)]. Conditions for immunoaffinity clean-up, HPLC and photo-derivatization were optimized in this study and successfully applied in assessment of airborne mycotoxins from a poultry house in Dalian, China. Fifty-two air samples were collected with AGI-30 air samplers using pure water as collection media. Twenty air samples (20/52, 38.46%) were positive for four toxins. Among the positive samples, airborne mycotoxin concentrations (mean+/-S.D.) for AFG(2), AFB(1), and ZEA were 0.189+/-0.024 (n=9), 0.080+/-0.003 (n=11) and 2.363+/-0.030 (n=5)ng/m(3) air, while the concentration for OTA was 8.530 (n=1)ng/m(3). No positive sample was found for either AFG(1) or AFB(2). A chicken may inhale 0.019-0.057 ng AFG(2), 0.013-0.019 ng AFB(1), 0.436-0.513 ng ZEA, and 1.706 ng OTA, respectively, in a day. A poultry worker may inhale 0.504-1.512 ng AFB(1), 0.752-2.28 ng AFG(2), 68.240 ng OTA, and 17.432-20.512 ng ZEA in a working day. This is the first report on airborne mycotoxins in poultry house. These data may have importance in animal and public health implications.
Kuperman, Roman G; Siciliano, Steven D; Römbke, Jörg; Oorts, Koen
2014-07-01
Although it is widely recognized that microorganisms are essential for sustaining soil fertility, structure, nutrient cycling, groundwater purification, and other soil functions, soil microbial toxicity data were excluded from the derivation of Ecological Soil Screening Levels (Eco-SSL) in the United States. Among the reasons for such exclusion were claims that microbial toxicity tests were too difficult to interpret because of the high variability of microbial responses, uncertainty regarding the relevance of the various endpoints, and functional redundancy. Since the release of the first draft of the Eco-SSL Guidance document by the US Environmental Protection Agency in 2003, soil microbial toxicity testing and its use in ecological risk assessments have substantially improved. A wide range of standardized and nonstandardized methods became available for testing chemical toxicity to microbial functions in soil. Regulatory frameworks in the European Union and Australia have successfully incorporated microbial toxicity data into the derivation of soil threshold concentrations for ecological risk assessments. This article provides the 3-part rationale for including soil microbial processes in the development of soil clean-up values (SCVs): 1) presenting a brief overview of relevant test methods for assessing microbial functions in soil, 2) examining data sets for Cu, Ni, Zn, and Mo that incorporated soil microbial toxicity data into regulatory frameworks, and 3) offering recommendations on how to integrate the best available science into the method development for deriving site-specific SCVs that account for bioavailability of metals and metalloids in soil. Although the primary focus of this article is on the development of the approach for deriving SCVs for metals and metalloids in the United States, the recommendations provided in this article may also be applicable in other jurisdictions that aim at developing ecological soil threshold values for protection of
DEFF Research Database (Denmark)
Hansen, Martin; Krogh, Kristine Andersen; Halling-Sørensen, Bent
2011-01-01
... Martin Hansen , Kristine A. Krogh , Bent Halling ... in a 22 mL PLE cell : firstly by flushing the sample with heptane to remove unwanted matrix components (inverse- PLE , i- PLE ) and secondly, performing internal clean-up (ic- PLE ) and eluting the steroid hormones by attaching an ...
International Nuclear Information System (INIS)
Kurjane, N.; Kirsfinks, M.; Hagina, E.; Socnevs, A.
2001-01-01
Study was undertaken to evaluate plasma concentrations of interleukin-1beta (IL-1), interleukin-6 (IL-6), and adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) and P-selectin in persons who participated in the clean-up work of the Chernobyl NPP explosion aftereffects. 40 Chernobyl clean-up workers suffering from most common neurological diseases - polyneuropathy and encephalopathy, and 40 healthy blood donors were analyzed for plasma levels of IL-6, IL1-β, sICAM-1 and sP-selectin 13 years after the accident. The documented external radiation dosage to the investigated Chernobyl clean-up workers was exposed from 0,009 to 0,28 Gy. Significantly elevated plasma concentrations of IL-6 and P-selectin but not of IL-1β were found in Chernobyl clean-up labourers as compared to those in healthy blood donors. (p<0.01). There was no obvious association of cytokine and adhesion molecule levels with radiation doses, as individuals working in the Chernobyl area in 1986 at a time when the external radiation exposure was higher revealed similar plasma concentrations if compared to those of a later period of time (1987-1990). (authors)
Directory of Open Access Journals (Sweden)
Yan Li
2018-01-01
Full Text Available A bidirectional B-spline QR method (BB-sQRM for the study on the crack control of the reinforced concrete (RC beam embedded with shape memory alloy (SMA wires is presented. In the proposed method, the discretization is performed with a set of spline nodes in two directions of the plane model, and structural displacement fields are constructed by the linear combination of the products of cubic B-spline interpolation functions. To derive the elastoplastic stiffness equation of the RC beam, an explicit form is utilized to express the elastoplastic constitutive law of concrete materials. The proposed model is compared with the ANSYS model in several numerical examples. The results not only show that the solutions given by the BB-sQRM are very close to those given by the finite element method (FEM but also prove the high efficiency and low computational cost of the BB-sQRM. Meanwhile, the five parameters, such as depth-span ratio, thickness of concrete cover, reinforcement ratio, prestrain, and eccentricity of SMA wires, are investigated to learn their effects on the crack control. The results show that depth-span ratio of RC beams and prestrain and eccentricity of SMA wires have a significant influence on the control performance of beam cracks.
International Nuclear Information System (INIS)
Wei, Jingsong; Yan, Hui
2014-01-01
Self-focusing is a well-researched phenomenon. Nanoscale spots can be achieved through self-focusing, which is an alternative method for achieving high-density data storage, high-resolution light imaging, and maskless nanolithography. Several research groups have observed that self-focusing spots can be reduced to nanoscale levels via incident laser power manipulation. Self-focusing spots can be analyzed by solving the nonlinear Schrödinger equation and the finite difference time domain method. However, both procedures are complex and time-consuming. In the present work, a multi-layer thin-lens self-focusing model that considers diffraction effects and changes of refractive index along the radial and film thickness directions is proposed to analyze the self-focusing behavior and traveling process of light beams intuitively. The self-focusing behaviors of As 2 S 3 are simulated, and results show that a nanoscale self-focusing spot with a radius of about 0.12 μm can be formed at the bottom of nonlinear sample when the incident laser power exceeds 4.25 mW. Our findings are basically consistent with experimental reports and provide a good method for analyzing and understanding the self-focusing process. An appropriate application schematic design is also provided
International Nuclear Information System (INIS)
Decking, W.
1995-11-01
In this thesis I analyze the effects of wiggler and undulator magnetic fields on the beam dynamics of electron/positron storage rings. DORIS III, DESY's synchrotron radiation source is taken as an example. Wigglers and undulators are used for the production of synchrotron radiation or to control beam sizes in storage rings. Their introduction in the lattices of storage rings causes some problems due to the strong nonlinearities of the magnetic fields. Therefore a detailed analysis of the particle dynamics under the influence of wiggler magnetic fields and their field errors is necessary. This thesis provides such an analysis. The problem will be attacked analytically, numerically and experimentally. The analytic approach is based on the treatment of the appropriate Hamiltonian with perturbation theory. The magnetic fields are described with a Fourier series, which covers the main characteristics of wiggler and undulator fields. The main effect of wigglers and undulators is the excitation of fourth order synchro-betatron resonances. The description of field errors and other details of the magnetic fields is achieved by integrating over appropriately distributed current sheets. This allows the modeling of different parameters such as magnet pole width, periodicity errors and errors in the field gradients. (orig./WL)ons of motion in the fields calculated with this method can only be integrated numerically. This would be much too slow to be used in particle tracking codes. Therefore a transfer map b
Importance of beam-beam tune spread to collective beam-beam instability in hadron colliders
International Nuclear Information System (INIS)
Jin Lihui; Shi Jicong
2004-01-01
In hadron colliders, electron-beam compensation of beam-beam tune spread has been explored for a reduction of beam-beam effects. In this paper, effects of the tune-spread compensation on beam-beam instabilities were studied with a self-consistent beam-beam simulation in model lattices of Tevatron and Large Hodron Collider. It was found that the reduction of the tune spread with the electron-beam compensation could induce a coherent beam-beam instability. The merit of the compensation with different degrees of tune-spread reduction was evaluated based on beam-size growth. When two beams have a same betatron tune, the compensation could do more harm than good to the beams when only beam-beam effects are considered. If a tune split between two beams is large enough, the compensation with a small reduction of the tune spread could benefit beams as Landau damping suppresses the coherent beam-beam instability. The result indicates that nonlinear (nonintegrable) beam-beam effects could dominate beam dynamics and a reduction of beam-beam tune spread by introducing additional beam-beam interactions and reducing Landau damping may not improve the stability of beams
International Nuclear Information System (INIS)
Sahoo, N.K.; Thakur, S.; Senthilkumar, M.; Das, N.C.
2005-01-01
Thickness-dependent index non-linearity in thin films has been a thought provoking as well as intriguing topic in the field of optical coatings. The characterization and analysis of such inhomogeneous index profiles pose several degrees of challenges to thin-film researchers depending upon the availability of relevant experimental and process-monitoring-related information. In the present work, a variety of novel experimental non-linear index profiles have been observed in thin films of MgOAl 2 O 3 ZrO 2 ternary composites in solid solution under various electron-beam deposition parameters. Analysis and derivation of these non-linear spectral index profiles have been carried out by an inverse-synthesis approach using a real-time optical monitoring signal and post-deposition transmittance and reflection spectra. Most of the non-linear index functions are observed to fit polynomial equations of order seven or eight very well. In this paper, the application of such a non-linear index function has also been demonstrated in designing electric-field-optimized high-damage-threshold multilayer coatings such as normal- and oblique-incidence edge filters and a broadband beam splitter for p-polarized light. Such designs can also advantageously maintain the microstructural stability of the multilayer structure due to the low stress factor of the non-linear ternary composite layers. (orig.)
International Nuclear Information System (INIS)
Batra, Karuna; Mitra, Sugata; Subbarao, D.; Sharma, R.P.; Uma, R.
2005-01-01
The task for the present study is to make an investigation of self-similarity in a self-focusing laser beam both theoretically and numerically using graphical user interface based interactive computer simulation model in MATLAB (matrix laboratory) software in the presence of saturating ponderomotive force based and relativistic electron quiver based plasma nonlinearities. The corresponding eigenvalue problem is solved analytically using the standard eikonal formalism and the underlying dynamics of self-focusing is dictated by the corrected paraxial theory for slow self-focusing. The results are also compared with computer simulation of self-focusing by the direct fast Fourier transform based spectral methods. It is found that the self-similar solution obtained analytically oscillates around the true numerical solution equating it at regular intervals. The simulation results are the main ones although a feasible semianalytical theory under many assumptions is given to understand the process. The self-similar profiles are called as self-organized profiles (not in a strict sense), which are found to be close to Laguerre-Gaussian curves for all the modes, the shape being conserved. This terminology is chosen because it has already been shown from a phase space analysis that the width of an initially Gaussian beam undergoes periodic oscillations that are damped when any absorption is added in the model, i.e., the beam width converges to a constant value. The research paper also tabulates the specific values of the normalized phase shift for solutions decaying to zero at large transverse distances for first three modes which can, however, be extended to higher order modes
Nonlinear dynamics aspects of particle accelerators
International Nuclear Information System (INIS)
Jowett, J.M.; Turner, S.; Month, M.
1986-01-01
These proceedings contain the lectures presented at the named winter school. They deal with the application of dynamical systems to accelerator theory. Especially considered are the statistical description of charged-beam plasmas, integrable and nonintegrable Hamiltonian systems, single particle dynamics and nonlinear resonances in circular accelerators, nonlinear dynamics aspects of modern storage rings, nonlinear beam-beam resonances, synchro-betatron resonances, observations of the beam-beam interactions, the dynamics of the beam-beam interactions, beam-beam simulations, the perturbation method in nonlinear dynamics, theories of statistical equilibrium in electron-positron storage rings, nonlinear dissipative phenomena in electron storage rings, the dynamical aperture, the transition to chaos for area-preserving maps, special processors for particle tracking, algorithms for tracking of charged particles in circular accelerators, the breakdown of stability, and a personal perspective of nonlinear dynamics. (HSI)
Nonlinear dynamics aspects of particle accelerators. Proceedings
Energy Technology Data Exchange (ETDEWEB)
Jowett, J M; Turner, S; Month, M
1986-01-01
These proceedings contain the lectures presented at the named winter school. They deal with the application of dynamical systems to accelerator theory. Especially considered are the statistical description of charged-beam plasmas, integrable and nonintegrable Hamiltonian systems, single particle dynamics and nonlinear resonances in circular accelerators, nonlinear dynamics aspects of modern storage rings, nonlinear beam-beam resonances, synchro-betatron resonances, observations of the beam-beam interactions, the dynamics of the beam-beam interactions, beam-beam simulations, the perturbation method in nonlinear dynamics, theories of statistical equilibrium in electron-positron storage rings, nonlinear dissipative phenomena in electron storage rings, the dynamical aperture, the transition to chaos for area-preserving maps, special processors for particle tracking, algorithms for tracking of charged particles in circular accelerators, the breakdown of stability, and a personal perspective of nonlinear dynamics. (HSI).
Nonlinear Optical Terahertz Technology
National Aeronautics and Space Administration — We develop a new approach to generation of THz radiation. Our method relies on mixing two optical frequency beams in a nonlinear crystalline Whispering Gallery Mode...
Bazyka, O D; Belyi, D O
2017-12-01
To study the dynamics of circulatory system diseases during the 30 year period after irradiation, changes in the status of systolic function of heart left ventricle (LV) and the features of its remodeling in clean up workers (CW) of the accident at the Chernobyl nuclear power plant (ChNPP). It was examined 144 CW at ChNPP, including 52 patients, who survived acute radiation sick ness (ARS) grade of severity 1-3, and 105 non irradiated persons (control group - CG). CW have been divided into two subgroups: without signs of ARS (ARS0) and those who suffered from ARS. CW and CG patients were male who had no signs of cardiovascular, nervous, pulmonary or endocrine pathology prior to the Chernobyl accident. Their average age at the beginning of the accident was 33.9-37.7 years. The study program included clinical examina tion, echocardiography, retrospective and statistical analysis. Hypertensive heart disease (HHD) has developed in the CW, including the ARS convalescents, by 12 years, and ischemic heart disease (CHD) at 9-11 years is believed to be earlier than in comparable non irradiated patients. In the post accident period, there was an increased mean value of LV posterior wall (PW) thickness, interventricular septum (IVS), myocardium mass and myocardium mass normalized by body surface area. These indices grew with the increase of HHD duration. Over the 30 year follow up period, between CW and CG from 14.3 to 28.6 % of patients with LV increased volumes it was found a decreased ejection fraction (EF), what indicated the development of sys tolic LV dysfunction with the phenomena of left ventricular heart failure (HF). Reduction of EF correlated with increase of end systolic volume (ESV) having the highest statistical strength. In CW and persons of CG there was from 77.3 to 84.8 % of patients had clinical signs of HF with preserved EF. From this number, 56-63.6 % of patients had concentric and 18.8-26.7 % had eccentric LV hypertrophy (LVH), and in 6.1 to 15.6% of
International Nuclear Information System (INIS)
Aurelian, F.; Georgescu, D.; Popescu, M.
2006-01-01
closure, decommissioning and rehabilitation workings time, it is presented for the working staff the calculation of the supplementary effective doses, which it is exposed to, related to the working type, as it follows: - at the radioactive material relocation: 1.01 mSv/year; - at the stepping, leveling and encapsulation workings: 2.77 mSv/year; - at the underground equipment decommissioning: 1.12 mSv/year; - at the building demolition and underground equipment decommissioning the supplementary effective dose is: 0.5 mSv/year. After site remediation and clean-up of contaminated areas the limits stipulated by the Romanian Nuclear Authority are respected, as it follows: - the ecological restored surface areas and dumps fulfilled the conditions according to which specific activity is less or equal to 0.2 Bq/g and the gamma rate dose is less or equal to 0.3 v/h; - the hydrographic network waters conform to dose values stipulated by the Romanian Nuclear Authority. The calculated supplementary effective doses for the workers did not exceed the value of 20 mSv/year and the ones calculated for the population after the remediation are not exceeding 1 mSv/year. (authors)
International Nuclear Information System (INIS)
Lorec, Amelie
2016-01-01
France - a world leader in the whole nuclear power cycle - is also responsible for the clean-up and dismantling of its end-of-life nuclear facilities. Here, the CEA is considered to be a pioneer both in the project ownership of work sites and in the R and D for optimising the timescales, costs and safety of those work sites. Its responsibilities range from defining the most appropriate scenario, characterising the radiological state of equipment and decontaminating premises, carrying out dismantling and optimising the resulting waste. With this wide range of skills and the diversity of its facilities, the CEA Nuclear Energy Division is developing innovative solutions which are already the subject of industrial transfers. Two-thirds of France's end-of-life nuclear facilities belong to the CEA - a situation connected with its history. This implies setting up clean-up and dismantling work sites which have unprecedented scientific, human and financial challenges. Every regulated nuclear installation (INB) (nuclear reactors, laboratories, etc.) has a limited operating life. When it stops being used, it is first cleaned up (removal of radioactive substances), then dismantled (disassembly of components) in accordance with the baseline safety requirements, and finally decommissioned so that it can be used for other purposes or be demolished. Cleanup and dismantling operations concern all the facility's components, such as hot (shielded) cells which can be found in some laboratories. As the owner of its clean-up and dismantling projects, the CEA also devotes a significant amount of R and D to reducing the timescales, costs and waste from current and future programmes, while improving their safety. The resulting innovations often lead to industrial transfers. (authors)
Spatial and Time Dynamics of Non-Linear Vortices in Plasma Lens for High-Current Ion Beam Focusing
Goncharov, Alexei A.; Maslov, Vasyl I.; Onishchenko, Ivan N.; Tretyakov, Vitalij N.
2002-11-01
It is known from numerical simulation (see, for example, [1]) and from experiments (see, for example, [2]), that an electron density bunches as discrete vortices are long - living structures in vacuum. However, in laboratory experiments [2] it has been shown that the vortices are changed faster, when they are submersed in electrons, distributed around them. The charged plasma lens intended for a focussing of high-current ion beams, has the same crossed configuration of a radial electrical and longitudinal magnetic field [3], as only electron plasma. In this lens the vortical turbulence is excited [3]. The vortex - bunch and vortex - hole are rotated in the inverse directions in system of their rest. The instability development in initially homogeneous plasma causes that the vortices are excited by pairs. Namely, if the vortex - bunch of electrons is generated, near the vortex - hole of electrons is also generated. It is shown, that in nonuniform plasma the vortices behave is various in time. Namely, the vortex - bunch goes to area of larger electron density, and the vortex - hole goes to area of smaller electron density. The speed of the vortex - hole is less than speed of the vortex - bunch. It is shown, that the electron vortices, generated in the plasma lens, can result in to formation of spiral distribution of electron density. The physical mechanism of coalescence of electron vortices - bunches is proposed. 1.Driscoll C.F. et al. Plasma Phys. Contr. Fus. Res. 3 (1989) 507. 2.Kiwamoto Y. et al. Non-neutral plasma physics. Princeton. 1999. P. 99-105. 3.Goncharov A. et al. Plasma Phys. Rep. 20 (1994) 499.
Beam-beam interaction in e+-e- storage rings
International Nuclear Information System (INIS)
Le Duff, J.
1977-01-01
Colliding beams in electron-positron storage rings are discussed with particular reference to the space charge forces occuring during beam-beam interactions and their effect on beam current and consequently machine performance (maximum luminosity). The first section deals with linear beam-beam effects and discussses linear tune shift; the second section considers non-linear beam-beam effects and the creation on non-linear resonances. The last section poses questions of the possibility of extrapolating present results to future machines and discusses optimization of storage ring performance. (B.D.)
Kong, Wei-Jun; Liu, Shu-Yu; Qiu, Feng; Xiao, Xiao-He; Yang, Mei-Hua
2013-05-07
A simple and sensitive analytical method based on ultrasound-assisted solid-liquid extraction and immunoaffinity column clean-up coupled with high performance liquid chromatography and on-line post-column photochemical derivatization-fluorescence detection (USLE-IAC-HPLC-PCD-FLD) has been developed for simultaneous multi-mycotoxin determination of aflatoxins B1, B2, G1, G2 (AFB1, AFB2, AFG1, AFG2) and ochratoxin A (OTA) in 13 edible and medicinal nutmeg samples marketed in China. AFs and OTA were extracted from nutmeg samples by ultrasonication using a methanol : water (80 : 20, v/v) solution, followed by an IAC clean-up step. Different USL extraction conditions, pre-processing ways for nutmeg sample and clean-up columns for mycotoxins, as well as HPLC-PCD-FLD parameters (mobile phase, column temperature, elution procedure, excitation and emission wavelengths) were optimized. This method, which was appraised for analyzing nutmeg samples, showed satisfactory results with reference to limits of detection (LODs) (from 0.02 to 0.25 μg kg(-1)), limits of quantification (LOQs) (from 0.06 to 0.8 μg kg(-1)), linear ranges (up to 30 ng mL(-1) for AFB1, AFG1 and OTA and 9 ng mL(-1) for AFB2 and AFG2), intra- and inter-day variability (all application of developed method in nutmeg samples have elucidated that four samples were detected with contamination of AFs and one with OTA. AFB1 was the most frequently found mycotoxin in 30.8% of nutmeg samples at contamination levels of 0.73-16.31 μg kg(-1). At least two different mycotoxins were co-occurred in three samples, and three AFs were simultaneously detected in one sample.
Nonlinear transport of dynamic system phase space
International Nuclear Information System (INIS)
Xie Xi; Xia Jiawen
1993-01-01
The inverse transform of any order solution of the differential equation of general nonlinear dynamic systems is derived, realizing theoretically the nonlinear transport for the phase space of nonlinear dynamic systems. The result is applicable to general nonlinear dynamic systems, with the transport of accelerator beam phase space as a typical example
Nonlinearity in nanomechanical cantilevers
DEFF Research Database (Denmark)
Villanueva Torrijo, Luis Guillermo; Karabalin, R. B.; Matheny, M. H.
2013-01-01
Euler-Bernoulli beam theory is widely used to successfully predict the linear dynamics of micro-and nanocantilever beams. However, its capacity to characterize the nonlinear dynamics of these devices has not yet been rigorously assessed, despite its use in nanoelectromechanical systems developmen....... These findings underscore the delicate balance between inertial and geometric nonlinear effects in the fundamental mode, and strongly motivate further work to develop theories beyond the Euler-Bernoulli approximation. DOI: 10.1103/PhysRevB.87.024304...
DEFF Research Database (Denmark)
Clausen, Carl A. Balslev; Christiansen, Peter Leth; Torner, L.
1999-01-01
We show that with the quasi-phase-matching technique it is possible to fabricate stripes of nonlinearity that trap and guide light like waveguides. We investigate an array of such stripes and find that when the stripes are sufficiently narrow, the beam dynamics is governed by a quadratic nonlinear...... discrete equation. The proposed structure therefore provides an experimental setting for exploring discrete effects in a controlled manner. In particular, we show propagation of breathers that are eventually trapped by discreteness. When the stripes are wide the beams evolve in a structure we term...
Pescara benchmarks: nonlinear identification
Gandino, E.; Garibaldi, L.; Marchesiello, S.
2011-07-01
Recent nonlinear methods are suitable for identifying large systems with lumped nonlinearities, but in practice most structural nonlinearities are distributed and an ideal nonlinear identification method should cater for them as well. In order to extend the current NSI method to be applied also on realistic large engineering structures, a modal counterpart of the method is proposed in this paper. The modal NSI technique is applied on one of the reinforced concrete beams that have been tested in Pescara, under the project titled "Monitoring and diagnostics of railway bridges by means of the analysis of the dynamic response due to train crossing", financed by Italian Ministry of Research. The beam showed a softening nonlinear behaviour, so that the nonlinearity concerning the first mode is characterized and its force contribution is quantified. Moreover, estimates for the modal parameters are obtained and the model is validated by comparing the measured and the reconstructed output. The identified estimates are also used to accurately predict the behaviour of the same beam, when subject to different initial conditions.
Pescara benchmarks: nonlinear identification
International Nuclear Information System (INIS)
Gandino, E; Garibaldi, L; Marchesiello, S
2011-01-01
Recent nonlinear methods are suitable for identifying large systems with lumped nonlinearities, but in practice most structural nonlinearities are distributed and an ideal nonlinear identification method should cater for them as well. In order to extend the current NSI method to be applied also on realistic large engineering structures, a modal counterpart of the method is proposed in this paper. The modal NSI technique is applied on one of the reinforced concrete beams that have been tested in Pescara, under the project titled M onitoring and diagnostics of railway bridges by means of the analysis of the dynamic response due to train crossing , financed by Italian Ministry of Research. The beam showed a softening nonlinear behaviour, so that the nonlinearity concerning the first mode is characterized and its force contribution is quantified. Moreover, estimates for the modal parameters are obtained and the model is validated by comparing the measured and the reconstructed output. The identified estimates are also used to accurately predict the behaviour of the same beam, when subject to different initial conditions.
International Nuclear Information System (INIS)
Shibahara, Yuji; Izumi, Masanori; Nanko, Takashi; Tachibana, Mitsuo
2011-06-01
Manpower needs for the preparation and clean-up process on the dismantling of equipments in FUGEN 3rd/4th feedwater heater room conducted in 2008 were calculated with the management data evaluation system: PRODIA Code, and it was inspected whether a conventional evaluation model had applicability for large nuclear facilities such as FUGEN or not. It was confirmed that the conventional evaluation model had no applicability for FUGEN causing by the difference in the plant scale between JPDR and FUGEN bringing expansion of working area. The difference between the actual data and the calculated value was improved by reviewing of the evaluation model, and this reviewing process also brought a new evaluation model. (author)
Energy Technology Data Exchange (ETDEWEB)
NONE
2000-07-01
The aim of this study is to evaluate the sanitary risks for the populations frequenting the coast beaches affected by the fuel oils of the tanker Erika, after their cleaning up. This quantitative evaluation of sanitary risks is led according to a protocol developed jointly between the two institutes ( the national institute of industrial environment and risks, I.N.E.R.I.S., and the national institute of sanitary watch I.n.V.S.). It does not give the risks in function the residual pollution level of concerned beaches but supplies to the authorities elements of scientific information in order to allow them to choose criteria appropriate for the management of eventual residual risks. (N.C.)
International Nuclear Information System (INIS)
Hardy, D.
2006-01-01
'Full text:' The Municipalities of Port Hope and Clarington ('Municipalities') are committed to leading the clean- up and safe long-term management of historic low- level radioactive and hazardous wastes deposited in Port Granby (in the Municipality of Clarington) and several locations in the Municipality of Port Hope. They are supported by the Government of Canada through Atomic Energy of Canada Limited's (AECL) Low- Level Radioactive Waste Management Office (LLRWMO). The wastes are the result of radium and uranium processing in Port Hope by Eldorado since the 1930s. To establish the parameters of the clean- up, including the ability to veto the project, the local municipalities negotiated and signed a Legal Agreement with the Government of Canada in 2001. As a Responsible Authority, Natural Resources Canada has defined and approved the scope of the two projects. The LLRWMO is designated as the proponent. Accordingly, the LLRWMO is conducting the Environmental Assessment (EA) Studies and seeking approval of a preferred method of conducting the clean up for each municipality. The municipalities recognized that these large and complex environmental assessment studies would challenge the resources of citizens, municipal professional staff and politicians. Thus, the Legal Agreement specified that both municipalities would have funded staff to work together to coordinate and expedite the project. A Peer Review Team (PRT) would be retained by the municipalities and funded by the Government of Canada. The PRT is made up of experienced professionals led by Hardy Stevenson and Associates Limited in disciplines appropriate to the peer review tasks on hand. The PRT has brought a unique approach to the peer review. The PRT is headed by planners and social scientists trained to be sensitive to the 'people aspects' of the EA process as a major priority. They are supported by engineers and technical specialists. The team includes a physician with a family practice who is also an
Guo, Yuanming; Hu, Hongmei; Li, Tiejun; Xue, Lijian; Zhang, Xiaoning; Zhong, Zhi; Zhang, Yurong; Jin, Yanjian
2017-08-01
A simple, rapid, and novel method has been developed and validated for determination of seven indicator polychlorinated biphenyls in water samples by gas chromatography with electron capture detection. 1 L of water samples containing 30 g of anhydrous sodium sulfate was first liquid-liquid extracted with an automated Jipad-6XB vertical oscillator using n-hexane/dichloromethane (1:1, v/v). The concentrated extract was cleaned up by dispersive solid-phase extraction with 100 mg of primary secondary amine as sorbent material. The linearity of this method ranged from 1.25 to 100 μg/L, with regression coefficients ranging between 0.9994 and 0.9999. The limits of detection were in the ng/L level, ranging between 0.2 and 0.3 ng/L. The recoveries of seven spiked polychlorinated biphenyls with external calibration method at different concentration levels in tap water, lake water, and sea water were in the ranges of 85-112, 76-116, and 72-108%, respectively, and with relative standard deviations of 3.3-4.5, 3.4-5.6, and 3.1-4.8% (n = 5), respectively. The performance of the proposed method was compared with traditional liquid-liquid extraction and solid-phase extraction clean-up methods, and comparable efficiencies were obtained. It is concluded that this method can be successfully applied for the determination of polychlorinated biphenyls in different water samples. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
International Nuclear Information System (INIS)
Al-Haydari, D.
2011-01-01
This paper describes the role of the Municipal Peer Review Team (MPRT) for the Municipalities of Port Hope (Port Hope Project) and Clarington (Port Granby Project) for the clean-up of low level and historic radioactive waste. The purpose of the MPRT is to provide the municipalities with a team of experts to help assist their participation in the cleanup process. The peer review process has enabled the Municipalities of Port Hope and Clarington to participate in the decision-making processes as equal parties with the Port Hope Area Initiative Management Office and the Regulatory Authorities. Furthermore, the peer review process has stressed the need for a proactive management approach for low-level radioactive waste and marginally contaminated soil clean-ups. With the work of the MPRT, the Port Hope Project has been granted a facility licence (August, 2009). Both Projects have completed the detailed design phase, where the MPRT played a major role in the review of design documentation. The MPRT has developed an excellent working relationship with the Municipal staff and Mayors of Port Hope and Clarington. The MPRT effectively manages the 'people aspects' of the Port Hope and Port Granby Projects for the municipalities and assists in building transparency and trust in all Project activities. Collaborative, multi-disciplinary dialogue has been a key element to project success. Furthermore, the MPRT has become familiar with the local residents from attending community events and public meetings and has become a trusted source on all things Project related. (author)
Beam halo in high-intensity beams
International Nuclear Information System (INIS)
Wangler, T.P.
1993-01-01
In space-charge dominated beams the nonlinear space-charge forces produce a filamentation pattern, which in projection to the 2-D phase spaces results in a 2-component beam consisting of an inner core and a diffuse outer halo. The beam-halo is of concern for a next generation of cw, high-power proton linacs that could be applied to intense neutron generators for nuclear materials processing. The author describes what has been learned about beam halo and the evolution of space-charge dominated beams using numerical simulations of initial laminar beams in uniform linear focusing channels. Initial results are presented from a study of beam entropy for an intense space-charge dominated beam
Nonlinear Optics and Applications
Abdeldayem, Hossin A. (Editor); Frazier, Donald O. (Editor)
2007-01-01
Nonlinear optics is the result of laser beam interaction with materials and started with the advent of lasers in the early 1960s. The field is growing daily and plays a major role in emerging photonic technology. Nonlinear optics play a major role in many of the optical applications such as optical signal processing, optical computers, ultrafast switches, ultra-short pulsed lasers, sensors, laser amplifiers, and many others. This special review volume on Nonlinear Optics and Applications is intended for those who want to be aware of the most recent technology. This book presents a survey of the recent advances of nonlinear optical applications. Emphasis will be on novel devices and materials, switching technology, optical computing, and important experimental results. Recent developments in topics which are of historical interest to researchers, and in the same time of potential use in the fields of all-optical communication and computing technologies, are also included. Additionally, a few new related topics which might provoke discussion are presented. The book includes chapters on nonlinear optics and applications; the nonlinear Schrodinger and associated equations that model spatio-temporal propagation; the supercontinuum light source; wideband ultrashort pulse fiber laser sources; lattice fabrication as well as their linear and nonlinear light guiding properties; the second-order EO effect (Pockels), the third-order (Kerr) and thermo-optical effects in optical waveguides and their applications in optical communication; and, the effect of magnetic field and its role in nonlinear optics, among other chapters.
International Nuclear Information System (INIS)
Herr, W; Pieloni, T
2014-01-01
One of the most severe limitations in high-intensity particle colliders is the beam-beam interaction, i.e. the perturbation of the beams as they cross the opposing beams. This introduction to beam-beam effects concentrates on a description of the phenomena that are present in modern colliding beam facilities
The nuclear age. Cleaning up the mess
International Nuclear Information System (INIS)
Menezes, M.; Stunell, A.
2001-01-01
This paper focuses on just one essential component of a 'non nuclear' future - the management of nuclear waste. Waste produced by nuclear power is invariably contaminated by radioactivity. It is therefore a serious health and environmental hazard which requires special consideration. As residual radioactive contamination is generally very long lasting, the treatment and disposal options not only have to be robust in themselves, but also capable of retaining their integrity for hundreds, even thousands of years. Until now the debate over the issue of nuclear waste has been polarised; on the one hand there are those who see blocking a long-term solution to waste management as a powerful lever against further nuclear development. On the other, there are those who are in favour of a nuclear-powered future and who consequently have attempted to minimise the problem of dealing with nuclear waste. However, the time is now right for developing a long-term waste strategy for two reasons. Firstly we are confronted with reality, as nuclear plants coming to the end of their life are decommissioned, and secondly, the privatisation of the electricity generation market- has meant that nuclear cannot longer compete in the market with cheaper forms of energy generation and so new build is unlikely. Two options for storing waste have, in the main, been explored: surface storage and geological disposal with the option of retrieval. We believe that geological disposal is the only real option as it does not rely on future societal or climate stability to remain safe and secure. The most vital requirements for the success of finding a long-term solution are public support and legitimacy. Nirex's attempt to gain planning permission for the Rock Characterisation Facility and experience in other countries of gaining support for geological disposal bear this out
Mobile GAC system cleans up petroleum leak
International Nuclear Information System (INIS)
Smiddy, F.
1991-01-01
Industry experts have been aware of carbon technology's environmental benefits for more than a decade. These benefits derive in part from granular activated carbon's (GAC) physical properties, including attrition resistance, high surface area, adsorption rate and capacity. Most often used to remove dissolved organics, industrial solvents and other toxic chemicals from groundwater, wastewater and potable sources, GAC expedites EPA compliance and is ideal for a wide variety of remediation applications. Secondary benefits of GAC systems include decolorization, odor control and solvent recovery. Now, pressure-rated systems are available to improve remediation efficiency and speed compliance. Using high-quality GAC, these systems adsorb groundwater contaminants to less-than-detectable concentrations with minimum downtime. This paper reports on a hydrogeological study conducted to investigate the extent of contamination and make recommendations on the best technology available to begin remediating the site. Forty-five monitoring wells were installed to identify the plume's vertical and horizontal profiles, direction of flow and groundwater characteristics. Results were used to identify ideal locations for placing the purge wells necessary to begin remediation
Healthy collaboration cleans up Kathmandu | IDRC - International ...
International Development Research Centre (IDRC) Digital Library (Canada)
2011-02-04
Feb 4, 2011 ... The project's social environment. The focus for the project's work has been Kathmandu's Wards 19 and 20, two adjoining political ... Although the municipal drinking water should be boiled for safe consumption, most small ...
''Z'' Facility Dielectric Oil Clean-Up
International Nuclear Information System (INIS)
Alessandri, Daniel; Bloomquist, Doug; Donovan, Guy; Feltz, Greg; Grelle, Nibby; Guthrie, Doug; Harris, Mark; Horry, Mike; Lockas, Mike; Potter, Jimmy; Pritchard, Chuck; Steedly, Jim.
1999-01-01
In August of 1998 the Z facility leaked approximately 150 gallons of deionized water into the dielectric oil of the Energy Storage Section (ESS). After processing the oil to remove existing particulate and free water the dielectric breakdown strength increased from the mid 20kV range to values in excess of 40 kV. 40 kV is above historical operating levels of about 35 kV. This, however, was not enough to allow 90 kV charging of the Marx Generators in the ESS. Further analysis of the oil showed dissolved water at a saturated level (70 - 80 ppm) and some residual particulate contamination smaller than 3 microns. The dissolved water and particulate combination was preventing the 90 kV charging of the Marx Generators in the ESS. After consulting with the oil industry it was determined that nitrogen sparging could be used to remove the dissolved water. Further particulate filtering was also conducted. After approximately 20 hours of sparging the water content in the ESS was reduced to 42 ppm which enabled Marx charging to 90 kV
International Nuclear Information System (INIS)
Peelle, E.
1990-01-01
Successes in public involvement efforts for nuclear waste management are so few that they deserve careful documentation and analysis. This paper chronicles the goals, process, problems and outcomes of one such success, the Northwest Defense Waste Citizens Forum (CF), created by the DOE-Richland manager in 1986 to advise DOE on its plans for nuclear waste disposal and cleanup of the Hanford site n eastern Washington state. In the evolving, often-controversial, highly-visible area of agency-public interactions, citizen task forces (TFs) have been shown to be useful in developing public policy at the local level. Making them work at the state level is more problematic. This case shows that a diverse, two-state citizen group can make significant contributions to complex EIS evaluations with heavy technical components. The CFs principal contribution to public policy was communication of its findings to business and professional groups, to area political representatives and state agencies, thereby laying the ground work for refocusing the Northwest upon the need for action on DW cleanup at Hanford. In going well beyond NEPA requirements for public involvement in agency decision making, DOE-Richland demonstrated innovative ways of dealing with the difficult issues of public confidence and public trust by means of agency openness, responsiveness to citizen needs for information, and good faith two-way communication. The success of this pro-active DOE initiative was due to many factors including selecting the right issue (existing wastes), structuring the CF at a broad, regional level, and intensive implementation of trust-building strategies
Servicio de limpieza de departamentos Clean Up
Castañeda Miñan, Giulietta; Henna Takaesu, Pedro; Palma Binasco, Carlos
2016-01-01
Plantea que la tecnología pueda ser un medio de ayuda para satisfacer la necesidad de limpieza de los hogares de manera fácil y amigable para todo público, haciendo un paralelo, debe ser tan sencillo como ahora solicitamos un taxi. De igual forma vamos de la mano con el tema de Responsabilidad Social colaborando con clubes de madres y asociaciones de vasos de leche, para que las señoras asociadas sean las que provean el servicio de limpieza bajo nuestra orientación y guía. La solución l...
2001-01-01
After six months of work, the part of the ISR coming under EP Division has been emptied and refurbished. The area is now ready to start building the LHC experiments. People who know the ISR from way back are likely to be surprised when they push open the doors to the old collider. Whereas the part of the tunnel allocated to EP (Experimental Physics) Division now stands empty, a few months ago, it was piled high with odds and ends. For more than 20 years, this part of the former Intersecting Storage Rings, a full quarter of the loop, had been used as storage space. Both items of value and pure junk had been dumped there, ranging from detector prototypes and 30 years old pumps with signs saying 'not to be thrown out', down to planks, a beautiful velvet armchair, and hundreds of electricity racks. Aloïs Girardoz, lost in the huge ISR hall, which will now be used for building the muon chambers of CMS. An audit carried out in 1996 on the research sector storage areas and accelerators signalled an end t...
Slow clean-up for fast reactor
Banks, Michael
2008-05-01
The year 2300 is so distant that one may be forgiven for thinking of it only in terms of science fiction. But this is the year that workers at the Dounreay power station in Northern Scotland - the UK's only centre for research into "fast" nuclear reactors - term as the "end point" by which time the site will be completely clear of radioactive material. More than 180 facilities - including the iconic dome that housed the Dounreay Fast Reactor (DFR) - were built at at the site since it opened in 1959, with almost 50 having been used to handle radioactive material.
Shoreline clean-up methods : biological treatments
Energy Technology Data Exchange (ETDEWEB)
Massoura, S.T. [Oil Spill Response Limited, Southampton (United Kingdom)
2009-07-01
The cleanup of oil spills in shoreline environments is a challenging issue worldwide. Oil spills receive public and media attention, particularly in the event of a coastal impact. It is important to evaluate the efficiency and effectiveness of cleanup methods when defining the level of effort and consequences that are appropriate to remove or treat different types of oil on different shoreline substrates. Of the many studies that have compared different mechanical, chemical and biological treatments for their effectiveness on various types of oil, biological techniques have received the most attention. For that reason, this paper evaluated the effectiveness and effects of shoreline cleanup methods using biological techniques. It summarized data from field experiments and oil spill incidents, including the Exxon Valdez, Sea Empress, Prestige, Grand Eagle, Nakhodka, Guanabara Bay and various Gulf war oil spills. Five major shoreline types were examined, notably rocky intertidal, cobble/pebble/gravel, sand/mud, saltmarsh, and mangrove/sea-grass. The biological techniques that were addressed were nutrient enrichment, hydrocarbon-utilizing bacteria, vegetable oil biosolvents, plants, surf washing, oil-particle interactions and natural attenuation. The study considered the oil type, volume and fate of stranded oil, location of coastal materials, extent of pollution and the impact of biological techniques. The main factors that affect biodegradation of hydrocarbons are the volume, chemical composition and weathering state of the petroleum product as well as the temperature, oxygen availability of nutrients, water salinity, pH level, water content, and microorganisms in the shoreline environment. The interaction of these factors also affect the biodegradation of oil. It was concluded that understanding the fate of stranded oil can help in the development of techniques that improve the weathering and degradation of oil on complex shoreline substrates. 39 refs.
National Policies for cleaning up contaminated sites
Veenman, S.A.; Jörgens, H.; Lenschow, A.; Liefferink, D.
2014-01-01
Policies for the remediation of contaminated sites emerged relatively late as a subfield of environmental protection. The policy area is adjacent to other policies, such as waste policy, which often includes provisions on how to deal with waste dumps, as well as soil and groundwater protection
Progress and challenges in cleaning up Hanford
Energy Technology Data Exchange (ETDEWEB)
Wagoner, J.D. [Dept. of Energy, Richland, WA (United States)
1997-08-01
This paper presents captioned viewgraphs which briefly summarize cleanup efforts at the Hanford Site. Underground waste tank and spent nuclear fuel issues are described. Progress is reported for the Plutonium Finishing Plant, PUREX plant, B-Plant/Waste Encapsulation Storage Facility, and Fast Flux Test Facility. A very brief overview of costs and number of sites remediated and/or decommissioned is given.
Cleaning up the Streets of Denver
International Nuclear Information System (INIS)
Stegen, R.L.; Wood, T.R.; Hackett, J.R.; Sogue, A.
2006-01-01
Between 1913 and 1924, several Denver area facilities extracted radium from carnotite ore mined from the Paradox basin region of Colorado. Tailings or abandoned ores from these facilities were apparently incorporated into asphalt used to pave approximately 7.2 kilometers (4.5 miles) of streets in Denver. A majority of the streets are located in residential areas. The radionuclides are bound within the asphalt matrix and pose minimal risk unless they are disturbed. The City and County of Denver (CCoD) is responsible for controlling repairs and maintenance on these impacted streets. Since 2002, the CCoD has embarked on a significant capital improvement project to remove the impacted asphalt for secure disposal followed by street reconstruction. To date, Parsons has removed approximately 55 percent of the impacted asphalt. This paper discusses the history of the Denver Radium Streets and summarizes on-going project efforts. (authors)
Mijangos, L; Bizkarguenaga, E; Prieto, A; Fernández, L A; Zuloaga, O
2015-04-10
The present study is focused on the development of an analytical method based on focused ultrasonic solid-liquid extraction (FUSLE) followed by dispersive solid-phase extraction (dSPE) clean-up and liquid chromatography-triple quadrupole tandem mass spectrometry (LC-MS/MS) optimised for the simultaneous analysis of certain endocrine disrupting compounds (EDCs), including alkylphenols (APs), bisphenol A (BPA), triclosan (TCS) and several hormones and sterols in vegetables (lettuce and carrot) and amended soil samples. Different variables affecting the chromatographic separation, the electrospray ionisation and mass spectrometric detection were optimised in order to improve the sensitivity of the separation and detection steps. Under the optimised extraction conditions (sonication of 5min at 33% of power with pulse times on of 0.8s and pulse times off of 0.2s in 10mL of n-hexane:acetone (30:70, v:v) mixture using an ice bath), different dSPE clean-up sorbents, such as Florisil, Envi-Carb, primary-secondary amine bonded silica (PSA) and C18, or combinations of them were evaluated for FUSLE extracts before LC-MS/MS. Apparent recoveries and precision in terms of relative standard deviation (RSDs %) of the method were determined at two different fortification levels (according to the matrix and the analyte) and values in the 70-130% and 2-27% ranges, respectively, were obtained for most of the target analytes and matrices. Matrix-matched calibration approach and the use of labelled standards as surrogates were needed for the properly quantification of most analytes and matrices. Method detection limits (MDLs), estimated with fortified samples, in the ranges of 0.1-100ng/g for carrot, 0.2-152ng/g for lettuce and 0.9-31ng/g for amended soil were obtained. The developed methodology was applied to the analysis of 11 EDCs in both real vegetable bought in a local market and in compost (from a local wastewater treatment plant, WWTP) amended soil samples. Copyright © 2015
Ortiz Boyer, F; Fernández Romero, J M; Luque de Castro, M D; Quesada, J M
1999-03-01
A semi-automatic procedure for the continuous clean-up and concentration of several fat-soluble vitamins prior to their separation by HPLC and UV detection is reported. The procedure is based on the use of a minicolumn packed with aminopropylsilica as sorbent located prior to the chromatographic detection system. The overall process was developed and applied to the main liposoluble vitamins (A, D2, D3, E, K1, K3) and several hydroxy metabolites of vitamin D3 [25-(OH)-D3,24,25-(OH)2-D3 and 1,25-(OH)2-D3]. All the analytes were monitored at a compromise wavelength of 270 nm. Calibration graphs were constructed between 0.01 and 100 ng ml-1 for vitamin D2 and D3 and their hydroxy metabolites, between 0.1 and 100 ng ml-1 for vitamin A, K1 and K3 and between 1 and 100 ng ml-1 for vitamin E, with excellent regression coefficients (> or = 0.9901) in all cases. The precision was established at two concentration levels with acceptable RSDs in all instances (between 3.6 and 8.7%). The method was appropriate for the determination of vitamin D2, D3, K1 and K3 and the 24,25-dihydroxy and 25-hydroxy metabolites of vitamin D3 in human plasma. The method was applied to plasma samples spiked with the target analytes and the recoveries ranged between 78 and 109%.
Energy Technology Data Exchange (ETDEWEB)
Ressel, K
1993-06-01
Halogen hydrocarbons and above all chlorinated hydrocarbons are widespread harmful substances in soils and in groundwater. When cleaning up groundwater contamination, the contaminants are brought into the gas phase by strip processes. From the gas phase, the contaminants can be adsorbed on different carrier materials, mostly active carbon. One was searching for ways to regenerate this adsorption material. The mixed culture from a sea sediment most suitable for the decomposition of chlorinated hydrocarbons was optimized regarding its decomposition performance and was later used on the technical scale. In the decomposition experiments on the large technical scale, the cultures were lodged on filling bodies which has a much higher amount of gaps. In this case, an optimum supply of the micro-organisms with oxygen and methane is guaranteed, which is used as co-substrate. No intermediate product was found in a gas chromatography examination. The biologically occupied stage is situated between a desorption column and the active carbon filters, and reduces the load of harmful substances which can no longer be brought into the gas phase by stripping out. This has the advantage that it can be integrated in existing plants and can be adapted to any case of contamination by lodging adapted micro-organisms on it. The basis for each application must be separately researched. (orig.)
Ryu, Yeonsuk; Reid, Malcolm J; Thomas, Kevin V
2015-08-28
A reliable oxidative stress biomarker, 8-iso-prostaglandin F2α (8-iso-PGF2α), was for the first time quantitatively analysed in wastewater using an analytical method consisting of liquid chromatography-high resolution mass spectrometry coupled to immunoaffinity clean-up (IAC-LC-HRMS). Factors influencing the method's robustness were investigated, including analyte stability in sewage and enzymatic deconjugation with β-glucuronidase. The IAC-LC-HRMS method was linear over the range of 0.1-100ng/mL with correlation coefficient (R(2)) of 0.999. The quantification limits were sufficiently low to detect 8-iso-PGF2α in sewage (method quantification limit of 0.3ng/L) and precision, expressed as relative standard deviation was less than 7% and the accuracy expressed as relative recovery was in the 103-113% range. As a result, the application of the method to 24-h composite wastewater samples from Oslo showed 8-iso-PGF2α concentrations of 18.9-23.3ng/L for 8 days in March 2015. This study demonstrates a standard method to analyse 8-iso-PGF2α in sewage that will contribute to the further investigation of the potential use of 8-iso-PGF2α as a sewage biomarker for assessing the status of community health. Copyright © 2015 Elsevier B.V. All rights reserved.
Zhu, Minghua; Zhao, Hongxia; Xia, Deming; Du, Juan; Xie, Huaijun; Chen, Jingwen
2018-08-30
An accelerated solvent extraction (ASE) with in-cell clean-up method coupled to ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed to determine 21 antibiotics in sea cucumber. The analytes include 10 sulfonamides, 4 fluoroquinolones, 3 amphenicols, 2 beta-lactams, 1 lincosamide and trimethoprim. Optimal parameters of ASE method were obtained at 80 °C, 1 static cycle of 5 min with methanol/acetonitrile (1/1, v/v) using 2 g of C18 as adsorbent. Recoveries at 50.1-129.2% were achieved with RSD under 20%. Method detection limits ranged from 0.03 to 2.9 μg kg -1 . Compared to the reported ultrasound-assisted extraction method, the proposed method offered comparable extraction efficiency for sulfonamides from sea cucumber, but higher for other categories of antibiotics. This validated method was then successfully applied to sea cucumber samples and 9 antibiotics were detected with the highest concentration up to 57.7 μg kg -1 for norfloxacin. Copyright © 2018 Elsevier Ltd. All rights reserved.
Yang, Xihui; Hu, Yichen; Kong, Weijun; Chu, Xianfeng; Yang, Meihua; Zhao, Ming; Ouyang, Zhen
2014-11-01
A rapid, selective, and sensitive ultra-fast liquid chromatography with tandem mass spectrometry method was developed for the determination of ochratoxin A in traditional Chinese medicines based on vortex-assisted solid-liquid microextraction and aptamer-affinity column clean-up. Through optimizing the sample pretreatment procedures and chromatographic conditions, good linearity (r(2) ≥ 0.9993), low limit of detection (0.5-0.8 μg/kg), and satisfactory recovery (83.54-94.44%) expressed the good reliability and applicability of the established method in various traditional Chinese medicines. Moreover, the aptamer-affinity column, prepared in-house, showed an excellent feasibility owing to its specific identification of ochratoxin A in various kinds of selected traditional Chinese medicines. The maximum adsorption amount and applicability value were 188.96 ± 10.56 ng and 72.3%, respectively. The matrix effects were effectively eliminated, especially for m/z 404.2→358.0 of ochratoxin A. The application of the developed method for screening the natural contamination levels of ochratoxin A in 25 random traditional Chinese medicines on the market in China indicated that only eight samples were contaminated with low levels below the legal limit (5.0 μg/kg) set by the European Union. This study provided a preferred choice for the rapid and accurate monitoring of ochratoxin A in complex matrices. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Del Bubba, Massimo; Ancillotti, Claudia; Checchini, Leonardo; Fibbi, Donatella; Rossini, Daniele; Ciofi, Lorenzo; Rivoira, Luca; Profeti, Claudio; Orlandini, Serena; Furlanetto, Sandra
2018-01-30
A sensitive and reliable analytical method was developed for the simultaneous determination of five phthalate diesters and corresponding monoesters in human milk samples and infant formulas. The method involved a liquid-liquid extraction with a CH 2 Cl 2 /CH 3 OH/NaCl 30% 2/1/0.5 (v/v/v) mixture, the clean-up of the extract by size-exclusion chromatography (swelling and elution solvent: cyclohexane/ethyl acetate 9/1v/v), the derivatization of monoesters by trimethylsilyl-diazomethane and instrumental analysis by gas chromatography coupled with mass spectrometry. Recovery was in the range of 83-115% and precision was found between 9% and 21%. For phthalate diesters, method detection limits (MDLs) ranged from hundreds of ng/kg to 4.2μg/kg on a fresh weight milk (f.w.) basis, depending on blank contribution evaluated in matrix. Lower MDLs (0.03-0.8μg/kg f.w.) were achieved for corresponding monoesters. The proposed method was applied to the determination of target compounds in nine human milk samples and four infant formulas, confirming their presence in all samples. However, a generally higher contamination was assessed in artificial milk than in breast milk samples. Copyright © 2017 Elsevier B.V. All rights reserved.