Low and intermediate level radioactive waste in Mexico

International Nuclear Information System (INIS)

Paredes, L.C.; Ortiz, J.R.; Sanchez, S.

2002-01-01

Currently, it is necessary to establish, in a few years, a definitive repository for low and intermediate level radioactive waste in order to satisfy the necessities of Mexico for the next 50 years. Consequently, it is required to estimate the volumes of the radioactive waste generated annually, the stored volumes to-date and their projection to medium-term. On this subject, the annual average production of low and intermediate level radioactive waste from the electricity production by means of nuclear power reactors is 250 m 3 /y which consist of humid and dry solid waste from the 2 units of the Laguna Verde Nuclear Power plant having a re-use efficiency of effluents of 95%. On the other hand, the applications in medicine, industry and research generate 20 m 3 /y of solid waste, 280 m 3 /y of liquid waste and approximately 10 m 3 /y from 300 spent sealed radioactive sources. The estimation of the total volume of these waste to the year 2035 is 17500 m 3 corresponding to the 46% of the volume generated by the operation and maintenance of the 2 units of the Laguna Verde Nuclear Power plant, 34% to the decommissioning of these 2 units at the end of their useful life and 20% to the waste generated by applications in medicine, industry and research. (author)

Treatment and immobilization of intermediate level radioactive wastes

International Nuclear Information System (INIS)

Lerch, R.E.; Greenhalgh, W.O.; Partridge, J.A.; Richardson, G.L.

1977-01-01

This paper discusses a new program underway to develop and demonstrate treatment and immobilization technologies for intermediate level wastes (ILW) generated in the nuclear fuel cycle. Initial work has defined the sources, quantities and types of wastes which comprise ILW. Laboratory studies are underway to define treatment technologies for liquid ILW which contains volatile contaminants and to define immobilization parameters for the residues resulting from treatment of ILW. Immobilization agents initially being evaluated for the various residues include cement, urea-formaldehyde, and bitumen although other immobilization agents will be studied. The program also includes development of acceptable test procedures for the final immobilized products as well as development of proposed criteria for storage, transportation, and disposal of the immobilized ILW. 20 figures, 10 tables

Treatment and immobilization of intermediate-level radioactive wastes

International Nuclear Information System (INIS)

Lerch, R.E.; Greenhalgh, W.O.; Partridge, J.A.; Richardson, G.L.

1979-01-01

A new program underway at the Hanford Engineering Development Laboratory (HEDL) to develop and demonstrate treatment and immobilization technologies for intermediate-level wastes (ILW) generated in the nuclear fuel cycle is discussed. ILW are defined as those liquid and solid radioactive wastes, other than high-level wastes and fuel cladding hulls, that in packaged form have radiation dose readings greater than 200 millirem/hr at the packaged surface and 10 millirem/hr at three feet from the surface. The IAEA value of 10 4 Ci/m 3 for ILW defines the upper limit. For comparative purposes, reference is also made to certain aspects of low-level radioactive wastes (LLW). Initial work has defined the sources, quantities and types of wastes which comprise ILW. Because of the wide differences in composition (e.g., acids, salt solutions, resins and zeolites, HEPA filters, etc.) the wastes may require different treatments, particularly those wastes containing volatile contaminants. The various types of ILW have been grouped into categories amenable to similar treatment. Laboratory studies are underway to define treatment technologies for liquid ILW which contain volatile contaminants and to define immobilization parameters for the residues resulting from treatment of ILW. Immobilization agents initially being evaluated for the various residues include cement, urea-formaldehyde, and bitumen although other immobilization agents will be studied. The program also includes development of acceptable test procedures for the final immobilized products as well as development of proposed criteria for storage, transportation, and disposal of the immobilized ILW

A Theory of Liquidity and Regulation of Financial Intermediation

OpenAIRE

Emmanuel Farhi; Mikhail Golosov; Aleh Tsyvinski

2009-01-01

This paper studies a mechanism design model of financial intermediation. There are two informational frictions: agents receive unobservable shocks and can participate in markets by engaging in trades unobservable to intermediaries. Without regulations, intermediaries provide no risk sharing because of an externality arising from arbitrage opportunities. We identify a simple regulation -- a liquidity requirement -- that corrects such an externality by affecting the interest rate on the markets...

Intermediate Levels of Visual Processing

National Research Council Canada - National Science Library

Nakayama, Ken

1998-01-01

...) surface representation, here we have shown that there is an intermediate level of visual processing, between the analysis of the image and higher order representations related to specific objects; (2...

Acceptance criteria for deposition of low-level and intermediate-level radiation levels radioactive wastes

International Nuclear Information System (INIS)

2002-09-01

This norm establishes the criteria for acceptance low and intermediate radiation level for safe deposition in repositories, for assuring the protection of workers, population and environment against the hazardous effects of the ionizing radiations. The criteria of this norm applies to the low and intermediate radiation levels

CONDITIONING OF INTERMEDIATE-LEVEL WASTE AT FORSCHUNGSZENTRUM JUELICH GMBH

International Nuclear Information System (INIS)

Krumbach, H.

2003-01-01

This contribution to the group of low-level, intermediate, mixed and hazardous waste describes the conditioning of intermediate-level mixed waste (dose rate above 10 mSv/h at the surface) from Research Centre Juelich (FZJ). Conditioning of the waste by supercompaction is performed at Research Centre Karlsruhe (FZK). The waste described is radioactive waste arising from research at Juelich. This waste includes specimens and objects from irradiation experiments in the research reactors Merlin (FRJ-1) and Dido (FRJ-2) at FZJ. In principle, radioactive waste at Forschungszentrum Juelich GmbH is differentiated by the surface dose rate at the waste package. Up to a surface dose rate of 10 mSv/h, the waste is regarded as low-level. The radioactive waste described here has a surface dose rate above 10 mSv/h. Waste up to 10 mSv/h is conditioned at the Juelich site according to different conditioning methods. The intermediate-level waste can only be conditioned by supercompaction in the processing facility for intermediate-level waste from plant operation at Research Centre Karlsruhe. Research Centre Juelich also uses this waste cell to condition its intermediate-level waste from plant operation

The management of intermediate level wastes in Sweden

International Nuclear Information System (INIS)

Hultgren, Aa.; Thegerstroem, C.

1980-01-01

A brief overview of current practices and research in Sweden on the management of intermediate level wastes is given. Intermediate level wastes include spent resins, filters and core components from the six power reactors in operation; radioactive wastes from nuclear fuel development at Studsvik and from non-nuclear applications are a minor contribution. (Auth.)

Current issues in the management of low- and intermediate-level radioactive wastes from Ontario Hydro's CANDU reactors

International Nuclear Information System (INIS)

Krasznai, J.P.; Vaughan, B.R.; Williamson, A.S.

1990-01-01

Nuclear generating stations (NGSs) in Canada are operated by utilities in Ontario, Quebec, and New Brunswick. Ontario Hydro, with a committed nuclear program of 13,600 MW(electric) is the major producer of CANDU pressurized heavy-water reactor (PHWR) low- and intermediate-level radioactive wastes. All radioactive wastes with the exception of irradiated fuel are processed and retrievably stored at a centralized facility at the Bruce Nuclear Power Development site. Solid-waste classifications and annual production levels are given. Solid-waste management practices at the site as well as the physical, chemical, and radiochemical characteristics of the wastes are well documented. The paper summarizes types, current inventory, and estimated annual production rate of liquid waste. Operation of the tritium recovery facility at Darlington NGS, which removes tritium from heavy water and produces tritium gas in the process, gives rise to secondary streams of tritiated solid and liquid wastes, which will receive special treatment and packaging. In addition to the treatment of radioactive liquid wastes, there are a number of other important issues in low- and intermediate-level radioactive waste management that Ontario Hydro will be addressing over the next few years. The most pressing of these is the reduction of radioactive wastes through in-station material control, employee awareness, and improved waste characterization and segregation programs. Since Ontario Hydro intends to store retrievable wastes for > 50 yr, it is necessary to determine the behavior of wastes under long-term storage conditions

Projection to 2035 for the radioactive wastes of low and intermediate level in Mexico

International Nuclear Information System (INIS)

Paredes G, L.C.; Sanchez U, S.

2004-01-01

It is necessary to establish in few years a definitive warehouse for the radioactive waste of low and intermediate level, generated in the country and to satisfy the necessities of their confinement in the next ones 50 to 80 years. Therefore, it is required to be considered those volumes produced annually, those stored at the present and those estimated to medium and long term. The results of the simulation of 4 cases are presented, considering the operation from the 2 nuclear power reactors to 40 and 60 years, the use of the technology of current treatment and the use of super compaction of solids, as well as the importance in the taking of decision of the methodology for the dismantlement of each reactor to the finish of their useful life. At the moment the Nuclear Power Plant of Laguna Verde, produces an average of 250 m 3 /year of radioactive waste of low and intermediate level, constituted by solid dry wastes, humid solids and liquids. In the last 3 years, the power plant has reached an effectiveness of re utilization of effluents of 95%. On the other hand, in Mexico the non energetic applications of the radioisotopes, produce annually of the order of 20 m 3 /year of solid wastes, 280 m 3 /year of liquid wastes and 300 worn out radioactive sources. (Author)

Liquid level controller

International Nuclear Information System (INIS)

Mangus, J.D.; Redding, A.H.

1975-01-01

A system for maintaining two distinct sodium levels within the shell of a heat exchanger having a plurality of J-shaped modular tube bundles each enclosed in a separate shell which extends from a common base portion. A lower liquid level is maintained in the base portion and an upper liquid level is maintained in the shell enwrapping the long stem of the J-shaped tube bundles by utilizing standpipes with a notch at the lower end which decreases in open area the distance from the end of the stand pipe increases and a supply of inert gas fed at a constant rate to produce liquid levels, which will remain generally constant as the flow of liquid through the vessel varies

Teaching New Keynesian Open Economy Macroeconomics at the Intermediate Level

Science.gov (United States)

Bofinger, Peter; Mayer, Eric; Wollmershauser, Timo

2009-01-01

For the open economy, the workhorse model in intermediate textbooks still is the Mundell-Fleming model, which basically extends the investment and savings, liquidity preference and money supply (IS-LM) model to open economy problems. The authors present a simple New Keynesian model of the open economy that introduces open economy considerations…

MNE Entrepreneurial Capabilities at Intermediate Levels

DEFF Research Database (Denmark)

Hoenen, Anne K.; Nell, Phillip Christopher; Ambos, Björn

2014-01-01

at intermediate geographical levels differ from local subsidiaries and global corporate headquarters, and why those differences are important. We illustrate our arguments using data on European regional headquarters (RHQs). We find that RHQs' entrepreneurial capabilities depend on their external embeddedness...... and on the heterogeneous information that is generated through dissimilar markets within the region. Our study opens up for an interesting discussion of the independence of these mechanisms. In sum, we contribute to the understanding of the entrepreneurial role of intermediate units in general and RHQs in particular....

Pulse radiolysis study of the intermediates formed in ionic liquids. Intermediate spectra in the p-terphenyl solution in the ionic liquid methyltributylammonium bis[(trifluoromethyl)sulfonyl]imide

International Nuclear Information System (INIS)

Grodkowski, J.; Kocia, R.; Mirkowski, J.

2006-01-01

Room temperature ionic liquids (Il) are non-volatile,and non-flammable and serve as good solvents for various reactions, mainly for g reen processing . To understand the effect of these solvents on the chemical reactions, the rate constants of several elementary reactions in ionic liquids have been studied by the pulse radiolysis technique. In this study, the formation of intermediates derived from p-terphenyl (Tp) in the ionic liquid methyl tributylammonium bis[(trifluoromethyl)sulfonyl] imide (R 4 NNTf 2 ) solutions have been studied by pulse radiolysis as a part of broader studies concerning CO 2 reduction. The registered spectra can be explained by CO 2 reaction with solvated and dry electrons thus eliminating one path of TP ·- formation. Some TP ·- are formed by reaction of excited TP *- states with Tea. Direct reactions involving Tp, TP ·- , CO 2 and CO 2 ·- are too slow to be observed in pulse radiolysis time scale

The ARES High-level Intermediate Representation

Energy Technology Data Exchange (ETDEWEB)

Moss, Nicholas David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-03-03

The LLVM intermediate representation (IR) lacks semantic constructs for depicting common high-performance operations such as parallel and concurrent execution, communication and synchronization. Currently, representing such semantics in LLVM requires either extending the intermediate form (a signi cant undertaking) or the use of ad hoc indirect means such as encoding them as intrinsics and/or the use of metadata constructs. In this paper we discuss a work in progress to explore the design and implementation of a new compilation stage and associated high-level intermediate form that is placed between the abstract syntax tree and when it is lowered to LLVM's IR. This highlevel representation is a superset of LLVM IR and supports the direct representation of these common parallel computing constructs along with the infrastructure for supporting analysis and transformation passes on this representation.

Conditioning of intermediate-level waste at Forschungszentrum Juelich GmbH

International Nuclear Information System (INIS)

Krumbach, H.

2003-01-01

This contribution to the group of low-level, intermediate, mixed and hazardous waste describes the conditioning of intermediate-level mixed waste (dose rate above 10 mSv/h at the surface) from Research Centre Juelich (FZJ). Conditioning of the waste by supercompaction is performed at Research Centre Karlsruhe (FZK). The waste described is radioactive waste arising from research at Juelich. This waste includes specimens and objects from irradiation experiments in the research reactors Merlin (FRJ-1) and Dido (FRJ-2) at FZJ. In principle, radioactive waste at Forschungszentrum Juelich GmbH is differentiated by the surface dose rate at the waste package. Up to a surface dose rate of 10 mSv/h, the waste is regarded as low-level. The radioactive waste described here has a surface dose rate above 10 mSv/h. Waste up to 10 mSv/h is conditioned at the Juelich site according to different conditioning methods. The intermediate-level waste can only be conditioned by supercompaction in the processing facility for intermediate-level waste from plant operation at Research Centre Karlsruhe. Research Centre Juelich also uses this waste cell to condition its intermediate-level waste from plant operation. (orig.)

PEP liquid level system

International Nuclear Information System (INIS)

Lauritzen, T.; Sah, R.C.

1981-03-01

A liquid level system has been installed in the accelerator housing of the PEP storage ring. This instrument spans the entire 2.2 km circumference of the PEP project, and over one hundred readouts provide reference elevations which are used for the accurate alignment of accelerator components. The liquid level has proven to be extremely precise (+-0.10 mm) and quick to use, and it has contributed to the accurate alignment of PEP before beam turn-on. Since the liquid level readouts are rigidly attached to the accelerator housing, the liquid level has been a convenient means to monitor the settling of the accelerator housing

Effect of temperature during wood torrefaction on the formation of lignin liquid intermediates

Science.gov (United States)

Manuel Raul Pelaez-Samaniego; Vikram Yadama; Manuel Garcia-Perez; Eini Lowell; Armando G. McDonald

2014-01-01

Torrefaction enhances physical properties of lignocellulosic biomass and improves its grindability. Energy densification, via fuel pellets production, is one of the most promising uses of torrefaction. Lignin contributes to self-bonding of wood particles during pelletization. In biomass thermal pretreatment, part oflignin (in the form of lignin liquid intermediates –...

Simulation methods of rocket fuel refrigerating with liquid nitrogen and intermediate heat carrier

Directory of Open Access Journals (Sweden)

O. E. Denisov

2014-01-01

Full Text Available Temperature preparation of liquid propellant components (LPC before fueling the tanks of rocket and space technology is the one of the operations performed by ground technological complexes on cosmodromes. Refrigeration of high-boiling LPC is needed to increase its density and to create cold reserve for compensation of heat flows existing during fueling and prelaunch operations of space rockets.The method and results of simulation of LPC refrigeration in the recuperative heat exchangers with heat carrier which is refrigerated by-turn with liquid nitrogen sparging. The refrigerating system consists of two tanks (for the chilled coolant and LPC, LPC and heat carrier circulation loops with heat exchanger and system of heat carrier refrigeration in its tank with bubbler. Application of intermediate heat carrier between LPC and liquid nitrogen allows to avoid LPC crystallization on cold surfaces of the heat exchanger.Simulation of such systems performance is necessary to determine its basic design and functional parameters ensuring effective refrigerating of liquid propellant components, time and the amount of liquid nitrogen spent on refrigeration operation. Creating a simulator is quite complicated because of the need to take into consideration many different heat exchange processes occurring in the system. Also, to determine the influence of various parameters on occurring processes it is necessary to take into consideration the dependence of all heat exchange parameters on each other: heat emission coefficients, heat transfer coefficients, heat flow amounts, etc.The paper offers an overview of 10 references to foreign and Russian publications on separate issues and processes occurring in liquids refrigerating, including LPC refrigeration with liquid nitrogen. Concluded the need to define the LPC refrigerating conditions to minimize cost of liquid nitrogen. The experimental data presented in these publications is conformed with the application of

Investigations on cement/polymer Waste packages containing intermediate level waste and organic exchange resins

Energy Technology Data Exchange (ETDEWEB)

ELsourougy, M R; Zaki, A A; Aly, H F [Atomic energy authority, hot laboratory center, Cairo, (Egypt); Khalil, M Y [Nuclear engineering department, Alexandria university. Alexandria, (Egypt)

1995-10-01

Polymers can be added to cements to improve its nuclear waste immobilization properties. This trend in cementation processes is attracting attention and requiring through investigations. In this work, polymers of different kinds were added to ordinary portland cement for the purpose of solidifying intermediate level liquid wastes and organic ion exchange resins. Epoxy polymer such as Kemapoxy-150 reduced the leaching rate of cesium compared to cement alone. Latex to cement ratio less than 4% caused an increase in leaching rate of cesium. When cesium was absorbed to an organic resin its leachability was improved. 5 figs., 4 tabs.

Investigations on cement/polymer Waste packages containing intermediate level waste and organic exchange resins

International Nuclear Information System (INIS)

ELsourougy, M.R.; Zaki, A.A.; Aly, H.F.; Khalil, M.Y.

1995-01-01

Polymers can be added to cements to improve its nuclear waste immobilization properties. This trend in cementation processes is attracting attention and requiring through investigations. In this work, polymers of different kinds were added to ordinary portland cement for the purpose of solidifying intermediate level liquid wastes and organic ion exchange resins. Epoxy polymer such as Kemapoxy-150 reduced the leaching rate of cesium compared to cement alone. Latex to cement ratio less than 4% caused an increase in leaching rate of cesium. When cesium was absorbed to an organic resin its leachability was improved. 5 figs., 4 tabs

Fluorescent optical liquid-level sensor

International Nuclear Information System (INIS)

Weiss, Jonathan D.

2000-01-01

An optical method of detecting a liquid level is presented that uses fluorescence radiation generated in an impurity-doped glass or plastic slab. In operation, the slab is inserted into the liquid and pump light is coupled into it so that the light is guided by the slab-air interface above the liquid and escapes into the liquid just below its surface. Since the fluorescence is generated only in that section of the slab above the liquid, the fluorescence power will monotonically decrease with increasing liquid level. Thus, a relationship can be established between any signal proportional to it and the liquid level. Because optical fibers link the pump source and the detector of fluorescence radiation to the sensor, no electrical connections are needed in or near the liquid. Their absence vastly decreases the hazard associated with placing a liquid-level sensor in a potentially explosive environment. A laboratory prototype, consisting of a methyl styrene slab doped with an organic dye, has been built and successfully tested in water. Its response to liquid level when pumped by a tunable argon-ion laser at 476, 488, and 496 nm, and by a blue LED, is presented and shown to be consistent with theory. The fluorescence spectra, optical efficiency, temperature, and other effects are also presented and discussed. (c) 2000 Society of Photo-Optical Instrumentation Engineers

Storage for low-level and intermediate-level radioactive wastes

International Nuclear Information System (INIS)

1992-11-01

The objective of this report was to assess whether three nominated sites in Norway for underground storage of low-level and intermediate-level radioactive wastes would comply with safety standards and applicable laws and regulations. The site selection criteria are described and the report evaluates the technical, environmental and socio-economic suitability of the different sites. The site selection process eliminated two of the nominated sites, whereas one site was singled out. 28 refs., 14 figs., 10 tabs

PNGMDR - Characterisation of intermediate-level long-lived wastes

International Nuclear Information System (INIS)

2014-12-01

This document presents the status of the characterization of intermediate-level long-lived wastes which are warehoused on exploited EDF sites or which will be produced during the deconstruction of first-generation reactors. It addresses aspects related to characterisation and packaging of wastes produced before 2015. More specifically, it addresses aspects related to contamination and to activation. Contamination is assessed by measurements whereas activation assessment is based on numerical simulations associated with measurements performed during parcel production. After having mentioned the concerned reactors, the document presents the methodology adopted for these assessments, and reports the progress status of the characterization process for these intermediate-level long-lived wastes

A liquid He-3 target system for use at intermediate energies

International Nuclear Information System (INIS)

Hassell, D.K.; Abegg, R.; Murdoch, B.T.; van Oers, W.J.H.; Soukup, J.

1981-04-01

A liquid 3 He target system with remote instrumentation and handling capabilities has been developed for experiments using the 180-525 MeV TRIUMF cyclotron. Helium-3 gas is liquefied by means of a 4 He cryostat into a cylindrical target cell (4.4 cm diameter, 1.6 cm thick) and maintained during operation at approximately 1.6 K. This provides an areal target density of approximately 2.7 x 10 22 He-3 nuclei/cm 2 (128 mg/cm 2 ), suitable for intermediate energy proton scattering. (author)

Progress on the national low level radioactive waste repository and national intermediate level waste store

International Nuclear Information System (INIS)

Perkins, C.

2003-01-01

The Australian Government is committed to establishing two purpose-built facilities for the management of Australia's radioactive waste; the national repository for disposal of low level and short-lived intermediate level ('low level') waste, and the national store for storage of long-lived intermediate level ('intermediate level') waste. It is strongly in the interests of public security and safety to secure radioactive waste by disposal or storage in facilities specially designed for this purpose. The current arrangements where waste is stored under ad hoc arrangements at hundreds of sites around Australia does not represent international best practice in radioactive waste management. Environmental approval has been obtained for the national repository to be located at Site 40a, 20 km east of Woomera in South Australia, and licences are currently being sought from the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) to site, construct and operate the facility. The national repository may be operating in 2004 subject to obtaining the required licences. The national store will be located on Australian Government land and house intermediate level waste produced by Australian Government departments and agencies. The national store will not be located in South Australia. Short-listing of potentially suitable sites is expected to be completed soon

Deep geologic repository for low and intermediate radioactive level waste in Canada

International Nuclear Information System (INIS)

Liu Jianqin; Li Honghui; Sun Qinghong; Yang Zhongtian

2012-01-01

Ontario Power Generation (OPG) is undergoing a project for the long-term management of low and intermediate level waste (LILW)-a deep geologic repository (DGR) project for low and intermediate level waste. The waste source term disposed, geologic setting, repository layout and operation, and safety assessment are discussed. It is expected to provide reference for disposal of low and intermediate level waste that contain the higher concentration of long-lived radionuclides in China. (authors)

The management of intermediate-level radioactive wastes arising from reprocessing operations

International Nuclear Information System (INIS)

Elsden, A.D.

1984-01-01

The reprocessing of spent nuclear fuel results in the generation of radioactive wastes in the form of liquids, gases and solids. This paper outlines the principles and major elements of the waste management systems currently in use or under development for the category of waste known as intermediate-level wastes. To enable implementation of an optimized waste management system, engineering process evaluations, development and design in the following areas are required: The definition of cost effective options taking account of constraints which may arise from other operations in the overall system, e.g. from transport requirements or from criteria derived from environmental impact assessments of alternative disposal routes; Plant and equipment development to enable acceptable system and active plant operations on an industrial scale; Safety and reliability studies to ensure adequate protection of both the general public and plant operators during all stages of the waste management system including disposal

Liquid level measurement in high level nuclear waste slurries

International Nuclear Information System (INIS)

Weeks, G.E.; Heckendorn, F.M.; Postles, R.L.

1990-01-01

Accurate liquid level measurement has been a difficult problem to solve for the Defense Waste Processing Facility (DWPF). The nuclear waste sludge tends to plug or degrade most commercially available liquid-level measurement sensors. A liquid-level measurement system that meets demanding accuracy requirements for the DWPF has been developed. The system uses a pneumatic 1:1 pressure repeater as a sensor and a computerized error correction system. 2 figs

Intermediate-Level Knowledge in Child-Computer Interaction

DEFF Research Database (Denmark)

Barendregt, Wolmet; Torgersson, Olof; Eriksson, Eva

2017-01-01

Based on an analysis of all papers at IDC from 2003 to 2016 this paper urges the Child-Computer Interaction (CCI) field to start formulating intermediate-level knowledge, in the form of e.g. strong concepts. Our analysis showed that 40% of all papers at the Interaction Design and Children...... conference presents the design of an artefact accompanied by an evaluation (to which we will refer as 'artefact-centered' papers). While exploring the design space in the form of artefacts is important and valuable, it can be argued that those artefact-centered papers generally make a smaller contribution...... to the field as a whole, which is also visible in the number of citations to such papers in comparison to the number of citations to other kinds of papers. As a first step towards more intermediate-level knowledge, we have thus attempted to formulate and ground three suggestions for strong concepts in CCI...

Communication: Anomalous temperature dependence of the intermediate range order in phosphonium ionic liquids

International Nuclear Information System (INIS)

Hettige, Jeevapani J.; Kashyap, Hemant K.; Margulis, Claudio J.

2014-01-01

In a recent article by the Castner and Margulis groups [Faraday Discuss. 154, 133 (2012)], we described in detail the structure of the tetradecyltrihexylphosphonium bis(trifluoromethylsulfonyl)-amide ionic liquid as a function of temperature using X-ray scattering, and theoretical partitions of the computationally derived structure function. Interestingly, and as opposed to the case in most other ionic-liquids, the first sharp diffraction peak or prepeak appears to increase in intensity as temperature is increased. This phenomenon is counter intuitive as one would expect that intermediate range order fades as temperature increases. This Communication shows that a loss of hydrophobic tail organization at higher temperatures is counterbalanced by better organization of polar components giving rise to the increase in intensity of the prepeak

Policy and technical considerations for intermediate-level and low-level radioactive waste

International Nuclear Information System (INIS)

Anon.

1977-01-01

This section has addressed issues, topics, and considerations related to low-level and intermediate-level wastes that are basic to developing and establishing environmental radiation protection criteria for radioactive wastes. Applicability of criteria, criteria considerations for sites, control of radiological impact to the population, and long-term considerations are discussed

Progress on the national low level radioactive waste repository and national intermediate level waste store

International Nuclear Information System (INIS)

Perkins, C.

2001-01-01

Over the last few years, significant progress has been made towards siting national, purpose-built facilities for Australian radioactive waste. In 2001, after an eight year search, a preferred site and two alternatives were identified in central-north South Australia for a near-surface repository for Australian low level (low level and short-lived intermediate level) radioactive waste. Site 52a at Everts Field West on the Woomera Prohibited Area was selected as the preferred site as it performs best against the selection criteria, particularly with respect to geology, ground water, transport and security. Two alternative sites, Site 45a and Site 40a, east of the Woomera-Roxby Downs Road, were also found to be highly suitable for the siting of the national repository. A project has commenced to site a national store for intermediate (long-lived intermediate level) radioactive waste on Commonwealth land for waste produced by Commonwealth agencies. Public input has been sought on relevant selection criteria

Liquid level control system for vapour generator

International Nuclear Information System (INIS)

Singh, G.

1984-01-01

A system for regulating the liquid level in a vapor generator, in which the incoming flow of feed liquid is regulated in response to the difference between the measured liquid level and a reference level, the difference between the exiting vapor mass flow rate and the incoming liquid mass flow rate, and a function of the measured incoming liquid temperature. The temperature function produces a gain value, which increases in response to decreasing incoming liquid temperature. The purpose of the temperature function is to stabilize the level control under transient conditions (e.g. sudden lose of load). (author)

PIC-container for containment and disposal of low and intermediate level radioactive wastes

International Nuclear Information System (INIS)

Araki, Kunio; Shinji, Yoshimasa; Maki, Yasuro; Ishizaki, Kanjiro; Minegishi, Keiichi; Sudoh, Giichi.

1981-03-01

Steel fiber reinforced polymer-impregnated concrete (SFPIC) has been investigated for low and intermediate level radioactive waste containers. The present study has been carried out by the following stages. A) Preliminary evaluation: 60 L size container for cold and hot tests. B) Evaluation of size effect: 200 L size container for cold tests. The 60 L and 200 L containers were designed as pressure-container (without equalizer) for 500 kg/cm 2 and 700 kg/cm 2 . Polymerization of impregnated methylmethacrylate monomer for stage-A and B were performed by 60 Co-γ ray radiation and thermal catalytic polymerization, respectively. Under the loading of 500 kg/cm 2 and 700 kg/cm 2 -outside hydraulic pressure, these containers were kept in their good condition. The observed maximum strains were about 1380 x 10 -6 and 3950 x 10 -6 at the outside central position of container body for circumferential direction of the 60 L and 200 L container, respectively. An accelerated leaching test was performed by charging the concentrate of the liquid radioactive waste from JMTR in JAERI into the container. Although they were immersed in deionized water for 400 days, nuclides were not leached from the container. From results of various tests, it was evaluated that the SFPIC-container was suitable for containment and disposal of low and intermediate level radioactive wastes. There was not any great difference between the two size containers for the physical and chemical properties except in their preparation process. (author)

Two-dimensional simulation of intermediate-sized bubbles in low viscous liquids using counter diffusion lattice Boltzmann method

Energy Technology Data Exchange (ETDEWEB)

Ryu, Seungyeob, E-mail: syryu@kaeri.re.kr [Korea Atomic Energy Research Institute (KAERI), 1045 Daeduk-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Kim, Youngin; Kang, Hanok; Kim, Keung Koo [Korea Atomic Energy Research Institute (KAERI), 1045 Daeduk-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Ko, Sungho, E-mail: sunghoko@cnu.ac.kr [Department of Mechanical Design Engineering, Chungnam National University, 220 Gung-dong, Yuseong-gu, Daejeon 305-764 (Korea, Republic of)

2016-08-15

Highlights: • We directly simulate intermediate-sized bubbles in low viscous liquids. • The path instability and shape oscillation can be successfully simulated. • The motion of a pair bubble and bubble swarm is presented. • Bubbles with high-Reynolds-number can be simulated with under-resolved grids. • The counter diffusion multiphase method is feasible for the direct simulation of bubbly flows. - Abstract: The counter diffusion lattice Boltzmann method (LBM) is used to simulate intermediate-sized bubbles in low viscous liquids. Bubbles at high Reynolds numbers ranging from hundreds to thousands are simulated successfully, which cannot be done for the existing LBM versions. The characteristics of the path instability of two rising bubbles are studied for a wide range of Eotvos and Morton numbers. Finally, the study presented how bubble swarms move within the flow and how the flow surrounding the bubbles is affected by the bubble motions.

Radiological protection and the selection of management strategies for intermediate level wastes

International Nuclear Information System (INIS)

Hill, M.D.; Webb, G.A.M.

1982-01-01

This paper describes the steps involved in selecting management systems and an overall management strategy for intermediate level solid radioactive wastes. The radiological protection inputs to intermediate level waste management decisions are discussed, together with the results of preliminary radiological assessments of disposal options. Areas where further work is required are identified. (author)

Liquid waste handling facilities for a conceptual LWR spent fuel reprocessing complex

International Nuclear Information System (INIS)

Witt, D.C.; Bradley, R.F.

1978-01-01

The waste evaporator systems and the methods for evaporating the liquid wastes of various radioactivity levels are discussed. After the liquid wastes are evaporated and nitric acid is recovered the high-level liquid waste is incorporated into borosilicate glass and the intermediate-level liquid waste into concrete for final disposal

Liquidity policies and systemic risk

OpenAIRE

Adrian, Tobias; Boyarchenko, Nina

2013-01-01

The growth of wholesale-funded credit intermediation has motivated liquidity regulations. We analyze a dynamic stochastic general equilibrium model in which liquidity and capital regulations interact with the supply of risk-free assets. In the model, the endogenously time-varying tightness of liquidity and capital constraints generates intermediaries’ leverage cycle, influencing the pricing of risk and the level of risk in the economy. Our analysis focuses on liquidity policies’ implications ...

Rollover risk, liquidity and macroprudential regulation

OpenAIRE

Ahnert, Toni

2014-01-01

I study rollover risk in the wholesale funding market when intermediaries can hold liquidity ex ante and are subject to fire sales ex post. Precautionary liquidity restores multiple equilibria in a global rollover game. An intermediate liquidity level supports both the usual run equilibrium and an efficient equilibrium. I provide a uniqueness refinement to characterize the privately optimal liquidity choice. Because of fire sales, liquidity holdings are strategic substitutes. Intermediaries f...

Characterization of decontamination factors for evaporators used in the treatment of low and intermediate level liquid radioactive wastes

International Nuclear Information System (INIS)

Rood, L.B.; Law, C.G. Jr.

1972-01-01

Evaporator decontamination factors were studied as functions of boiloff rate, volume reduction, and feed pH. A bench-scale vertical tube evaporator operating on simulated intermediate level nuclear wastes was used. Decontamination factors were not found to be strong functions of volume reduction or boiloff below vapor velocities of 25 lb/ft 2 -hr. At higher vapor fluxes, splashing was encountered. Foaming occurred at a feed pH of 6 but not at higher values. The presence of radioisotopes in the feed had no effect on evaporator performance

The European Communities' research programme on management of low and intermediate level wastes

International Nuclear Information System (INIS)

Simon, R.; Cecille, L.

1989-01-01

In the European Communities' third R and D programme on Management and Disposal of Radioactive Wastes a large number of projects have been commissioned to develop treatment and conditioning processes for low and intermediate level wastes and to qualify the conditioned waste forms. The paper presents the main objectives of this research and summarizes some of the more important studies. In liquid waste treatment, the research includes processes to separate actinides by new extractive methods and application of selective inorganic ion exchangers as well as electrochemically controlled ion exchange processes and a series of purification methods involving membrane techniques. The most important issue of solid waste management in the programme is the treatment and conditioning of plutonium containing wastes, for which a strategic study had been commissioned to optimize the choice between different treatment and conditioning options. Processes being studied include two advanced decontamination techniques and a variety of conditioning methods for incinerator ash and fuel element hulls. Another task of the programme is devoted to the qualification of waste forms. This comprises the characterization of the most common low and intermediate level waste products with respect to leaching, waste form stability, radiation resistance and compatibility with the respective disposal environments. In the course of the programme, the development of methods for quality assurance and in particular quality control has become an important issue: the control of the nuclide inventory, of the chemical composition of the wastes and of the correct operation of treatment and conditioning processes is being investigated in special laboratories. (author). 21 refs, 4 tabs

Low and intermediate level disposal in Spain (El Cabril Facility)

International Nuclear Information System (INIS)

Zuloaga, P.

1997-01-01

El Cabril disposal facility is located in Southern Spain and was commissioned in October 1992. The main objective of this facility is the disposal of all low- and intermediate-level waste produced in Spain in a disposal system (Figure 1) consisting of concrete overpacks placed in concrete vaults. A drain control system exists in inspection galleries constructed beneath the disposal vaults. The facility also includes : 1) A treatment and conditioning shop (with incineration, non-NPP wastes segregation and conditioning, drum transfer into overpacks, supercompaction, liquid waste collection, and grout preparation and injection) 2) A waste form characterisation laboratory with means for non-destructive radiological characterisation and for destructive tests on the waste forms (specimens extractions, unskinning of drums, mechanical strength, leaching tests on specimens and full size packages) 3) A fabrication shop for overpacks construction 4) Auxiliary systems and buildings in support of operation, maintenance and surveillance of the facility. The paper deals with the design, the operating experience of the facility, the waste packages characterisation and acceptance practice and the reception and transport of the wastes from the producers to facilities. (author). 11 figs

Slow and fast pyrolysis of Douglas-fir lignin: Importance of liquid-intermediate formation on the distribution of products

NARCIS (Netherlands)

Zhou, Shuai; Pecha, Brennan; van Kuppevelt, Michiel; McDonald, Armando G.; Garcia-Perez, Manuel

2014-01-01

The formation of liquid intermediates and the distribution of products were studied under slow and fast pyrolysis conditions. Results indicate that monomers are formed from lignin oligomeric products during secondary reactions, rather than directly from the native lignin. Lignin from Douglas-fir

Melting of metallic intermediate level waste

Energy Technology Data Exchange (ETDEWEB)

Huutoniemi, Tommi; Larsson, Arne; Blank, Eva [Studsvik Nuclear AB, Nykoeping (Sweden)

2013-08-15

This report presents a feasibility study of a melting facility for core components and reactor internals. An overview is given of how such a facility for treatment of intermediate level waste might be designed, constructed and operated and highlights both the possibilities and challenges. A cost estimate and a risk analysis are presented in order to make a conclusion of the technical feasibility of such a facility. Based on the authors' experience in operating a low level waste melting facility, their conclusion is that without technical improvements such a facility is not feasible today. This is based on the cost of constructing and operating such a facility, in conjunction with the radiological risks associated with operation and the uncertain benefits to disposal and long term safety.

Melting of metallic intermediate level waste

International Nuclear Information System (INIS)

Huutoniemi, Tommi; Larsson, Arne; Blank, Eva

2013-08-01

This report presents a feasibility study of a melting facility for core components and reactor internals. An overview is given of how such a facility for treatment of intermediate level waste might be designed, constructed and operated and highlights both the possibilities and challenges. A cost estimate and a risk analysis are presented in order to make a conclusion of the technical feasibility of such a facility. Based on the authors' experience in operating a low level waste melting facility, their conclusion is that without technical improvements such a facility is not feasible today. This is based on the cost of constructing and operating such a facility, in conjunction with the radiological risks associated with operation and the uncertain benefits to disposal and long term safety

Liquid level detector

International Nuclear Information System (INIS)

Dean, A.P.; Pendleton, J.R.

1982-01-01

A device is described for locating the level of the liquid metal in a sodium cooled nuclear reactor by using a movable probe equipped to signal a phase change with null on arrival at the interface between two conductively differing media. (U.K.)

Liquid Level Sensing System

Science.gov (United States)

Korman, Valentin (Inventor); Wiley, John T. (Inventor); Duffell, Amanda G. (Inventor)

2014-01-01

A liquid level sensing system includes waveguides disposed in a liquid and distributed along a path with a gap between adjacent waveguides. A source introduces electromagnetic energy into the waveguides at a first end of the path. A portion of the electromagnetic energy exits the waveguides at a second end of the path. A detector measures the portion of the electromagnetic energy exiting the second end of the path.

Project Guarantee 1985. Final repository for low- and intermediate-level radioactive wastes: The system of safety barriers

International Nuclear Information System (INIS)

Anon.

1985-01-01

The safety barrier system for the type B repository for low- and intermediate-level waste is described. The barrier parameters which are relevant for safety analysis are quantified and associated error limits and data scatter are given. The aim of the report is to give a summary documentation of the safety analysis input data and their scientific background. For secure containment of radioactive waste safety barriers are used which effectively limit the release of radioactive material from the repository (release barriers) and effectively retard the entry of the original radioactive material into the biosphere (time barriers). In the case of low- and intermediate-level waste the technical safety barrier system comprises: waste solidification matrix (cement, bitumen and resin), immobilisation of the waste packages in containers using liquid cement, concrete repository containers, backfilling of remaining vacant storage space with special concrete, concrete lining of the repository caverns, sealing of access tunnels on final closure of the repository. Natural geological safety barriers - host rock and overlying formations - have the following important functions. Because of its stability, the host rock in the repository zone protects the technical safety barrier system from destruction caused by climatic effects and erosion for a sufficient length of time. It also provides for low water flow and favourable chemistry (reducing conditions)

Liquid metal level measurement

International Nuclear Information System (INIS)

Hale, J.C.; Leyland, K.S.

1982-01-01

A liquid metal level indicator is described which can be used to measure, in a stainless steel tank, the level of a nuclear reactor coolant such as sodium. The instrument, which is based on the eddy current induction effect, gives readings over substantially the full depth of the tank and indicates the sense of change of level. (U.K.)

Rollover risk, liquidity, and macro-prudential regulation

OpenAIRE

Ahnert, Toni

2014-01-01

I study rollover risk in the wholesale funding market when intermediaries can hold liquidity ex-ante and are subject to fire sales ex-post. I demonstrate that precautionary liquidity restores multiple equilibria in a global rollover game. An intermediate liquidity level supports both the usual run equilibrium and an efficient equilibrium. I provide a uniqueness refinement to characterize the privately optimal liquidity choice. Because of fire sales, liquidity holdings are strategic substitute...

Treatment of low level radioactive liquid waste containing appreciable concentration of TBP degraded products.

Science.gov (United States)

Valsala, T P; Sonavane, M S; Kore, S G; Sonar, N L; De, Vaishali; Raghavendra, Y; Chattopadyaya, S; Dani, U; Kulkarni, Y; Changrani, R D

2011-11-30

The acidic and alkaline low level radioactive liquid waste (LLW) generated during the concentration of high level radioactive liquid waste (HLW) prior to vitrification and ion exchange treatment of intermediate level radioactive liquid waste (ILW), respectively are decontaminated by chemical co-precipitation before discharge to the environment. LLW stream generated from the ion exchange treatment of ILW contained high concentrations of carbonates, tributyl phosphate (TBP) degraded products and problematic radio nuclides like (106)Ru and (99)Tc. Presence of TBP degraded products was interfering with the co-precipitation process. In view of this a modified chemical treatment scheme was formulated for the treatment of this waste stream. By mixing the acidic LLW and alkaline LLW, the carbonates in the alkaline LLW were destroyed and the TBP degraded products got separated as a layer at the top of the vessel. By making use of the modified co-precipitation process the effluent stream (1-2 μCi/L) became dischargeable to the environment after appropriate dilution. Based on the lab scale studies about 250 m(3) of LLW was treated in the plant. The higher activity of the TBP degraded products separated was due to short lived (90)Y isotope. The cement waste product prepared using the TBP degraded product was having good chemical durability and compressive strength. Copyright © 2011 Elsevier B.V. All rights reserved.

Aube's storage centre for low and intermediate level wastes: Annual report 2008

International Nuclear Information System (INIS)

2008-01-01

After a presentation of the ANDRA (the French national Agency for radioactive waste management), its missions, its facilities, and its financing, this report reviews the activity of its storage centre for low and intermediate level wastes located on the territory of three towns in the Aube district. It briefly describes the facilities, the different categories of liquid effluents and their associated networks. It indicates some important figures characterizing the centre's operation. It describes the main safety objectives, technical measures and results in terms of radioprotection. It reports the main events in the relationship with the safety authority. It also briefly describes the incidents and accidents which occurred in 2008. It presents and specifies some results of the numerous environmental analyses performed around the centre (radioactivity measurements in air, water, milk, mushrooms, fishes, and so on), comments the radiologic impact of releases, and actions to improve these results. It gives assessments of the amount of produced wastes and describes their processing and management. Information actions are presented and the CHSCT (Committee of hygiene, safety, and working conditions) are reported

Corrosion susceptibility of steel drums containing cemented intermediate level nuclear wastes

Science.gov (United States)

Duffó, Gustavo S.; Farina, Silvia B.; Schulz, Fátima M.; Marotta, Francesca

2010-10-01

Cementation processes are used as immobilization techniques for low or intermediate level radioactive waste for economical and safety reasons and for being a simple operation. In particular, ion-exchange resins commonly used for purification of radioactive liquid waste from nuclear reactors are immobilized before being stored to improve the leach resistance of the waste matrix and to maintain mechanical stability. Combustible solid radioactive waste can be incinerated and the resulting ashes can also be immobilized before storage. The immobilized resins and ashes are then contained in steel drums that may undergo corrosion depending on the presence of certain contaminants. The work described in this paper was aimed at evaluating the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins and incineration ashes containing different concentrations of aggressive species (mostly chloride and sulphate ions). A special type of specimen was designed to simulate the cemented waste in the drum. The evolution of the corrosion potential and the corrosion current density of the steel, as well as the electrical resistivity of the matrix were monitored over a time period of 1 year. The results show the deleterious effect of chloride on the expected lifespan of the waste containers.

Corrosion susceptibility of steel drums containing cemented intermediate level nuclear wastes

International Nuclear Information System (INIS)

Duffo, Gustavo S.; Farina, Silvia B.; Schulz, Fatima M.; Marotta, Francesca

2010-01-01

Cementation processes are used as immobilization techniques for low or intermediate level radioactive waste for economical and safety reasons and for being a simple operation. In particular, ion-exchange resins commonly used for purification of radioactive liquid waste from nuclear reactors are immobilized before being stored to improve the leach resistance of the waste matrix and to maintain mechanical stability. Combustible solid radioactive waste can be incinerated and the resulting ashes can also be immobilized before storage. The immobilized resins and ashes are then contained in steel drums that may undergo corrosion depending on the presence of certain contaminants. The work described in this paper was aimed at evaluating the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins and incineration ashes containing different concentrations of aggressive species (mostly chloride and sulphate ions). A special type of specimen was designed to simulate the cemented waste in the drum. The evolution of the corrosion potential and the corrosion current density of the steel, as well as the electrical resistivity of the matrix were monitored over a time period of 1 year. The results show the deleterious effect of chloride on the expected lifespan of the waste containers.

Colloids related to low level and intermediate level waste

International Nuclear Information System (INIS)

Ramsay, J.D.F.; Russell, P.J.; Avery, R.G.

1991-01-01

A comprehensive research investigation has been undertaken to improve the understanding of the potential role of colloids in the context of disposal and storage of low level and intermediate level waste immobilized in cement. Several topics have been investigated which include: (a) the study of the formation and characteristics of colloids in cement leachates; (b) the effects of the near-field aqueous chemistry on the characteristics of colloids in repository environments; (c) colloid sorption behaviour; (d) interactions of near-field materials with leachates; (e) characteristics of near-field materials in EC repository simulation tests; and (f) colloid migration behaviour. These experimental investigations should provide data and a basis for the development of transport models and leaching mechanisms, and thus relate directly to the part of the Task 3 programme concerned with migration and retention of radionuclides in the near field. 114 Figs.; 39 Tabs.; 12 Refs

Packaging and transport of low and intermediate level radioactive waste

International Nuclear Information System (INIS)

Smith, M.J.S.; Streatfield, R.E.

1987-02-01

The paper presents an overview of Nirex proposals for the packaging and transport of low and intermediate-level radioactive waste, as well as the regulatory requirements which must be met in such operations. (author)

ESL for Hotel/Hospitality Industry. Level: Advanced Beginner/Intermediate.

Science.gov (United States)

Western Suffolk County Board of Cooperative Educational Services, Northport, NY.

This document contains 16 lesson plans for an advanced beginning and intermediate course in work-related English for non-English- or limited-English-speaking entry-level employees in the hotel and hospitality industry. Course objectives are as follows: helping participants understand and use job-specific vocabulary; receive and understand…

Assessment of studies and researches on warehousing - High-level and intermediate-level-long-lived radioactive wastes - December 2012

International Nuclear Information System (INIS)

2013-01-01

This large report first presents the approach adopted for the study and research on the warehousing of high-level and intermediate-level-long-lived radioactive wastes. It outlines how reversible storage and warehousing are complementary, discusses the lessons learned from researches performed by the CEA on long duration warehousing, presents the framework of studies and researches performed since 2006, and presents the scientific and technical content of studies and researches (warehousing need analysis, search for technical options providing complementarity with storage, extension or creation of warehousing installations). The second part addresses high-level and intermediate-level-long-lived radioactive waste parcels, indicates their origins and quantities. The third part proposes an analysis of warehousing capacities: existing capacities, French industrial experience in waste parcel warehousing, foreign experience in waste warehousing. The fourth part addresses reversible storage in deep geological formation: storage safety functions, storage reversibility, storage parcels, storage architecture, chronicle draft. The fifth part proposes an inventory of warehousing needs in terms of additional capacities for the both types of wastes (high-level, and intermediate-level-long-lived), and discusses warehousing functionalities and safety objectives. The sixth and seventh parts propose a detailed overview of design options for warehousing installations, respectively for high-level and for intermediate-level-long-lived waste parcels: main technical issues, feasibility studies of different concepts or architecture shapes, results of previous studies and introduction to studies performed since 2011, possible evolutions of the HA1, HA2 and MAVL concepts. The eighth chapter reports a phenomenological analysis of warehousing and the optimisation of material selection and construction arrangements. The last part discusses the application of researches to the extension of the

Natural analogue study for low-and-intermediate level radioactive waste shallow burial disposal

International Nuclear Information System (INIS)

Gu Cunli; Fan Zhiwen; Huang Yawen; Cui Anxi; Liu Xiuzheng; Zhang Jinshen

1995-01-01

The paper makes a comparison of low-and-intermediate level radioactive waste shallow burial disposal with Chinese ancient tombs in respects of siting, engineering structures, design principle and construction procedures. Results showed that Chinese ancient tombs are very good analogue for low-and-intermediate level radioactive waste shallow burial disposal. Long-term preservation of ancient tombs and buried objects demonstrated that low-and-intermediate level radioactive waste shallow burial disposal would be safe if suitable sites were selected, reasonable engineering structures and good backfill materials were adopted, and scientific construction procedures were followed. The paper reports for the first time the testing results of certain ancient tomb backfill materials. The results indicated that the materials have so low a permeability as 1.5 x 10 -8 cm/s , and strong adsorption to radionuclides Co and Cs with the distribution coefficients of 1.4 x 10 4 mL/g and 2.1 x 10 4 mL/g, and the retardation factors of 4.4 x 10 4 and 7.7 x 10 4 respectively. Good performance of these materials is important assurance of long-term preservation of the ancient tombs. These materials may be considered to be used as backfill materials in low-and-intermediate level radioactive shallow burial disposal. (4 figs., 10 tabs.)

Status and advice of the low and intermediate level radioactive waste disposal sites in China

International Nuclear Information System (INIS)

Teng Keyan; Lu Caixia

2012-01-01

With the rapid development of nuclear power industry in China, as well as the decommissioning of the nuclear facilities, and the process of radioactive waste management, a mount of the low and intermediate level radioactive solid wastes will increase rapidly. How to dispose the low and intermediate level radioactive solid wastes, that not only related to Chinese nuclear energy and nuclear technology with sustainable development, but also related to the public health, environment safety. According to Chinese « long-term development plan of nuclear power (2005- 2020) », when construct the nuclear power, should simultaneous consider the sites that dispose the low and intermediate level radioactive waste, In order to adapt to the needs that dispose the increasing low and intermediate level radioactive waste with development of nuclear power. In the future, all countries are facing the enormous challenge of nuclear waste disposal. (authors)

Efficient Lewis Acid Ionic Liquid-Catalyzed Synthesis of the Key Intermediate of Coenzyme Q10 under Microwave Irradiation

Directory of Open Access Journals (Sweden)

Thomas Efferth

2010-12-01

Full Text Available An efficient synthesis of a valuable intermediate of coenzyme Q10 by microwave-assisted Lewis acidic ionic liquid (IL-catalyzed Friedel-Crafts alkylation is reported. The acidity of six [Etpy]BF4-based ionic liquids was characterized by means of the FT-IR technique using acetonitrile as a molecular probe. The catalytic activities of these ionic liquids were correlated with their Lewis acidity. With increasing Lewis acid strength of the ionic liquids, their catalytic activity in the Friedel-Crafts reaction increased, except for [Etpy]BF4-AlCl3. The effects of the reaction system, the molar fraction of Lewis acid in the Lewis acid ILs and heating techniques were also investigated. Among the six Lewis acid ionic liquids tested [Etpy]BF4-ZnCl2 showed the best catalytic activity, with a yield of 89% after a very short reaction time (150 seconds. This procedure has the advantages of higher efficiency, better reusability of ILs, energy conservation and eco-friendliness. The method has practical value for preparation of CoQ10 on an industrial scale.

Method of processing low-level radioactive liquid wastes

International Nuclear Information System (INIS)

Matsunaga, Ichiro; Sugai, Hiroshi.

1984-01-01

Purpose: To effectively reduce the radioactivity density of low-level radioactive liquid wastes discharged from enriched uranium conversion processing steps or the likes. Method: Hydrazin is added to low-level radioactive liquid wastes, which are in contact with iron hydroxide-cation exchange resins prepared by processing strongly acidic-cation exchange resins with ferric chloride and aqueous ammonia to form hydrorizates of ferric ions in the resin. Hydrazine added herein may be any of hydrazine hydrate, hydrazine hydrochloride and hydranine sulfate. The preferred addition amount is more than 100 mg per one liter of the liquid wastes. If it is less than 100 mg, the reduction rate for the radioactivety density (procession liquid density/original liquid density) is decreased. This method enables to effectively reduce the radioactivity density of the low-level radioactive liquid wastes containing a trace amount of radioactive nucleides. (Yoshihara, H.)

Development of an efficient and economical small scale management scheme for low and intermediate-Level radioactive waste and its impact on the environment

International Nuclear Information System (INIS)

Salomon, A.Ph.; Panem, J.A.; Manalastas, H.C.; Cortez, S. L.; Paredes, C.H.; Bartolome, Z.M.

1976-05-01

This paper describes the efforts made towards the establishment of a pilot-scale management system for the low and intermediate-level radioactive wastes of the Atomic Research Center. The past and current practices in handling radioactive wastes are discussed and the assessment of their capabilities to meet the projections on the waste production is presented. The future waste management requirements of the Center was evaluated and comparative studies on the Lime-Soda and Phosphate Processes were conducted on simulated and raw liquid wastes with initial activity ranging from 10 -4 uCi/ml to 10 -2 uCi/ml, to establish the ideal parameters for best attaining maximum removal of radioactivity in liquids. The effectiveness of treatment was evaluated in terms of the decontamination factor, DF, obtained

High fidelity simulation and analysis of liquid jet atomization in a gaseous crossflow at intermediate Weber numbers

Energy Technology Data Exchange (ETDEWEB)

Li, Xiaoyi, E-mail: lixy2@utrc.utc.com; Soteriou, Marios C. [United Technologies Research Center, East Hartford, Connecticut 06108 (United States)

2016-08-15

Recent advances in numerical methods coupled with the substantial enhancements in computing power and the advent of high performance computing have presented first principle, high fidelity simulation as a viable tool in the prediction and analysis of spray atomization processes. The credibility and potential impact of such simulations, however, has been hampered by the relative absence of detailed validation against experimental evidence. The numerical stability and accuracy challenges arising from the need to simulate the high liquid-gas density ratio across the sharp interfaces encountered in these flows are key reasons for this. In this work we challenge this status quo by presenting a numerical model able to deal with these challenges, employing it in simulations of liquid jet in crossflow atomization and performing extensive validation of its results against a carefully executed experiment with detailed measurements in the atomization region. We then proceed to the detailed analysis of the flow physics. The computational model employs the coupled level set and volume of fluid approach to directly capture the spatiotemporal evolution of the liquid-gas interface and the sharp-interface ghost fluid method to stably handle high liquid-air density ratio. Adaptive mesh refinement and Lagrangian droplet models are shown to be viable options for computational cost reduction. Moreover, high performance computing is leveraged to manage the computational cost. The experiment selected for validation eliminates the impact of inlet liquid and gas turbulence and focuses on the impact of the crossflow aerodynamic forces on the atomization physics. Validation is demonstrated by comparing column surface wavelengths, deformation, breakup locations, column trajectories and droplet sizes, velocities, and mass rates for a range of intermediate Weber numbers. Analysis of the physics is performed in terms of the instability and breakup characteristics and the features of downstream

Containers for packaging of solid and intermediate level radioactive wastes

International Nuclear Information System (INIS)

1993-01-01

Low and intermediate level radioactive wastes are generated at all stages in the nuclear fuel cycle and also from the medical, industrial and research applications of radiation. These wastes can potentially present risks to health and the environment if they are not managed adequately. Their effective management will require the wastes to be safely stored, transported and ultimately disposed of. The waste container, which may be defined as any vessel, drum or box, made from metals, concrete, polymers or composite materials, in which the waste form is placed for interim storage, for transport and/or for final disposal, is an integral part of the whole package for the management of low and intermediate level wastes. It has key roles to play in several stages of the waste management process, starting from the storage of raw wastes and ending with the disposal of conditioned wastes. This report provides an overview of the various roles that a container may play and the factors that are important in each of these roles. This report has two main objectives. The first is to review the main requirements for the design of waste containers. The second is to provide advice on the design, fabrication and handling of different types of containers used in the management of low and intermediate level radioactive solid wastes. Recommendations for design and testing are given, based on the extensive experience available worldwide in waste management. This report is not intended to have any regulatory status or objectives. 56 refs, 16 figs, 10 tabs

Selection of liquid-level monitoring method for the Oak Ridge National Laboratory inactive liquid low-level waste tanks, remedial investigation/feasibility study

International Nuclear Information System (INIS)

1994-11-01

Several of the inactive liquid low-level waste (LLLW) tanks at Oak Ridge National Laboratory contain residual wastes in liquid or solid (sludge) form or both. A plan of action has been developed to ensure that potential environmental impacts from the waste remaining in the inactive LLLW tank systems are minimized. This document describes the evaluation and selection of a methodology for monitoring the level of the liquid in inactive LLLW tanks. Criteria are established for comparison of existing level monitoring and leak testing methods; a preferred method is selected and a decision methodology for monitoring the level of the liquid in the tanks is presented for implementation. The methodology selected can be used to continuously monitor the tanks pending disposition of the wastes for treatment and disposal. Tanks that are empty, are scheduled to be emptied in the near future, or have liquid contents that are very low risk to the environment were not considered to be candidates for installing level monitoring. Tanks requiring new monitoring equipment were provided with conductivity probes; tanks with existing level monitoring instrumentation were not modified. The resulting data will be analyzed to determine inactive LLLW tank liquid level trends as a function of time

Brazilian low and intermediate level radioactive waste disposal and environmental conservation areas

International Nuclear Information System (INIS)

Uemura, George; Cuccia, Valeria

2013-01-01

Low and intermediate level radioactive waste should be disposed off in proper disposal facilities. These facilities must include unoccupied areas as protection barriers, also called buffer zone. Besides that, Brazilian environmental laws require that certain enterprises must preserve part of their area for environmental conservation. The future Brazilian low and intermediate level waste repository (RBMN) might be classified as such enterprise. This paper presents and discusses the main Brazilian legal framework concerning different types of conservation areas that are allowed and which of them could be applied to the buffer zones of RBMN. The possibility of creating a plant repository in the buffer zone is also discussed. (author)

Experimental study on intermediate level radioactive waste processing

International Nuclear Information System (INIS)

Nagakura, Tadashi; Abe, Hirotoshi; Okazawa, Takao; Hattori, Seiichi; Maki, Yasuro

1977-01-01

In the disposal of intermediate level radioactive wastes, multilayer package will be adopted. The multilayer package consists of cement-solidified waste and a container such as a drum - can with concrete liner or a concrete container. So, on the waste to be cement-solidified in such container, experimental study was carried out as follows. (1) Cement-solidification method. (2) Mechanical behaviour of cement-solidified waste. The mechanical behaviour of the containers was studied by the finite element method and experiment, and the function of pressure-balancing valves was also studied. The following data on processing intermediate level radioactive wastes were obtained. (1) In the case of cement-solidified waste, the data to select the suitable solidifying material and the standard mixing proportion were determined. (2) The basic data concerning the uniaxial compressive strength of cement-solidified waste, the mechanical behaviour of cement-solidified waste packed in a drum under high hydrostatic pressure, the shock response of cement-solidified waste at the time of falling and so on were obtained. (3) The pressure-balancing valves worked at about 0.5 Kg/cm 2 pressure difference inside and outside a container, and the deformation of a drum cover was 10 to 13 mm. In case of the pressure difference less than 0,5 Kg/cm 2 , the valves shut, and water flow did occur. (auth.)

Solid and liquid radioactive waste treatment

International Nuclear Information System (INIS)

Rzyski, B.M.

1989-01-01

The technology for the treatment of low - and intermediate-level radioactive solid and liquid wastes is somewhat extensive. Some main guidance on the treatment methods are shown, based on informations contained in technical reports and complementary documents. (author) [pt

Steam generation device with heat exchange between a liquid metal coolant and the feedwater

International Nuclear Information System (INIS)

Malaval, C.

1983-01-01

The invention is particularly applicable to a liquid metal fast breeder reactor plant, the liquid metal being sodium. The steam generation device is described in detail, it allows to get an upper liquid metal level without turbulence and an easier passage for the shock wave towards the steam generator up to the liquid metal level without being laterally reflected back to the intermediate heat exchangers [fr

Feasibility of large volume casting cementation process for intermediate level radioactive waste

International Nuclear Information System (INIS)

Chen Zhuying; Chen Baisong; Zeng Jishu; Yu Chengze

1988-01-01

The recent tendency of radioactive waste treatment and disposal both in China and abroad is reviewed. The feasibility of the large volume casting cementation process for treating and disposing the intermediate level radioactive waste from spent fuel reprocessing plant in shallow land is assessed on the basis of the analyses of the experimental results (such as formulation study, solidified radioactive waste properties measurement ect.). It can be concluded large volume casting cementation process is a promising, safe and economic process. It is feasible to dispose the intermediate level radioactive waste from reprocessing plant it the disposal site chosen has resonable geological and geographical conditions and some additional effective protection means are taken

Development of the remediation strategy for the Dounreay intermediate level waste shaft

International Nuclear Information System (INIS)

McWhirter, A.F.

1998-01-01

The development of Fast Reactor Technology within the United Kingdom began in the mid 1950's and continued until 1994. It was concentrated at the United Kingdom Atomic Energy Authority site at Dounreay on the north coast of Scotland. During the construction of the site's low level liquid effluent discharge facility, a vertical access shaft was constructed which, when the discharge facility was completed, was sealed at the seaward end and allowed to fill naturally with water. It was then licensed by the Scottish Office Environmental Department as a disposal facility for what is now categorized as Intermediate Level Waste (ILW). Waste was disposed of to this facility from 1959 until 1977 when a hydrogen explosion in the air space above the shaft took place causing damage to the head works. Since that time UKAEA has maintained the shaft in a state of care and maintenance pending a decision on its long term future. During 1996 and 1997 detailed option studies were carried out which demonstrated that retrieval of the waste from the shaft and its subsequent above ground repackaging, conditioning and storage, represented the Best Practicable Environmental Option and UKAEA made this recommendation to the UK Government in November 1997. This recommendation was accepted by Government and, as a result, the present project to retrieve material has now begun. This paper describes the history of the facility, the options explored and the decision process by which the final strategy was determined. (author)

Vertical Integration at Junior and Intermediate Levels. School Research Newsletter.

Science.gov (United States)

Marklund, Inger, Ed.; Hanse, Mona-Britt, Ed.

1984-01-01

In recent years, there has been a rapid growth of interest in Sweden in vertically integrated classes in compulsory schools, especially at junior high school and intermediate grade levels. This development is supported in various ways by the curriculum, partly because it puts more emphasis than previous curricula on the occurrence of teaching…

Treatment of low- and intermediate-level solid radioactive wastes

International Nuclear Information System (INIS)

1983-01-01

One of the essential aims in the waste management is to reduce as much as possible the waste volumes to be stored or disposed of, and to concentrate and immobilize as much as possible the radioactivity contained in the waste. This document describes the treatment of low- and intermediate-level solid waste prior to its conditioning for storage and disposal. This report aims primarily at compiling the experience gained in treating low- and intermediate-active solid wastes, one of the major waste sources in nuclear technology. Apart from the description of existing facilities and demonstrated handling schemes, this report provides the reader with the basis for a judgement that facilitates the selection of appropriate solutions for a given solid-waste management problem. It thus aims at providing guidelines in the particular field and indicates new promising approaches that are actually under investigation and development

Low- and intermediate-level waste management practices in Canada

International Nuclear Information System (INIS)

Charlesworth, D.H.

1982-05-01

Low- and intermediate-level wastes arise in Canada from the operation of nuclear power stations, nuclear research establishments, nuclear fuel and radioisotope production facilities, as well as from many medical, research and industrial organizations. Essentially all of the solid radioactive wastas are stored in a retrievable fashion at five waste management areas from which a portion is expected to be transferred to future disposal facilities. Waste processing for volume reduction and stabilization is becoming an increasingly important part of low-level waste management because of the advantages it provides for both interim storage currently, and permanent disposal in the future

Comprehensive determination of macrolide antibiotics, their synthesis intermediates and transformation products in wastewater effluents and ambient waters by liquid chromatography-tandem mass spectrometry.

Science.gov (United States)

Senta, Ivan; Krizman-Matasic, Ivona; Terzic, Senka; Ahel, Marijan

2017-08-04

Macrolide antibiotics are a prominent group of emerging contaminants frequently found in wastewater effluents and wastewater-impacted aquatic environments. In this work, a novel analytical method for simultaneous determination of parent macrolide antibiotics (azithromycin, erythromycin, clarithromycin and roxithromycin), along with their synthesis intermediates, byproducts, metabolites and transformation products in wastewater and surface water was developed and validated. Samples were enriched using solid-phase extraction on Oasis HLB cartridges and analyzed by reversed-phase liquid chromatography coupled to electrospray ionization tandem mass spectrometry. The target macrolide compounds were separated on an ACE C18 PFP column and detected using multiple reaction monitoring in positive ionization polarity. The optimized method, which included an additional extract clean-up on strong anion-exchange cartridges (SAX), resulted in high recoveries and accuracies, low matrix effects and improved chromatographic separation of the target compounds, even in highly complex matrices, such as raw wastewater. The developed method was applied to the analysis of macrolide compounds in wastewater and river water samples from Croatia. In addition to parent antibiotics, several previously unreported macrolide transformation products and/or synthesis intermediates were detected in municipal wastewater, some of them reaching μg/L levels. Moreover, extremely high concentrations of macrolides up to mg/L level were found in pharmaceutical industry effluents, indicating possible importance of this source to the total loads into ambient waters. The results revealed a significant contribution of synthesis intermediates and transformation products to the overall mass balance of macrolides in the aquatic environment. Copyright © 2017. Published by Elsevier B.V.

Non-contact optical Liquid Level Sensors

Science.gov (United States)

Kiseleva, L. L.; Tevelev, L. V.; Shaimukhametov, R. R.

2016-06-01

Information about characteristics of the optical liquid level sensor are present. Sensors are used to control of the light level limit fluid - water, kerosene, alcohol, solutions, etc. Intrinsically safe, reliable and easy to use. The operating principle of the level sensor is an optoelectronic infrared device.

The packaging and transport of low and intermediate level radioactive wastes

International Nuclear Information System (INIS)

Grover, J.R.; Price, M.S.T.

1985-01-01

Up to the present time, the majority of the radioactive waste which has been transported in the United Kingdom has been low level waste for disposal in the trenches of the shallow burial site operated by British Nuclear Fuels plc at Drigg and also the packaged waste destined for sea disposal in the annual operation. However, the main bulk of the low and intermediate level wastes which have been generated over the last quarter century remain in store at the various nuclear sites where it originated. Before significant packaging and transport of intermediate level wastes takes place it is desirable to examine the sources and types of wastes, the immobilisation and packaging processes and plants, the transport, and the problems of handling of packages at future land repositories. Optimisation of the packaging and transport must take account of both the upstream and downstream con=straints as well as the implications of complying with both the IAEA Transport Regulations and radiological protection guidelines. Packages for sea disposal must in addition comply with the requirements of the London Dumping Convention and the NEA guidelines. (author)

Disposal Options for Low and Intermediate-Level Radioactive Waste: Comparative Study

International Nuclear Information System (INIS)

Abdellatif, M.M.

2013-01-01

This study presents the status of current disposal options for Low and Intermediate- Level Radioactive Waste (LILRW) generated in different countries and outlines the potential for future disposal option/s of these wastes in Egypt. Since approaches used in other countries may provide useful lessons for managing Egyptian radioactive wastes. This study was based on data for19 countries repositories and we focused on 6 countries, which considered as leaders in the field of disposal of rad waste. Several countries have plans for repositories which are sufficiently advanced that it was based on their own of their extensive experience with nuclear power generation and with constructing and operating LLRW disposal facilities. On the other hand, our programme for site selection and host rock characterization for low and intermediate level radioactive waste disposal is under study. We are preparing our criteria for selecting a national repository for LIL rad waste.

Ultrasonic level sensors for liquids under high pressure

Science.gov (United States)

Zuckerwar, A. J.; Mazel, D. S.; Hodges, D. Y.

1986-01-01

An ultrasonic level sensor of novel design continuously measures the level of a liquid subjected to a high pressure (up to about 40 MPa), as is sometimes required for the effective transfer of the liquid. The sensor operates as a composite resonator fabricated from a standard high-pressure plug. A flat-bottom hole is machined into the plug along its center line. An ultrasonic transducer is bonded rigidly to the interior surface of the bottom wall, while the exterior surface is in contact with the liquid. Although the bottom wall is designed to satisfy the pressure code, it is still sufficiently thin to permit ready excitation of the axisymmetric plate modes of vibration. The liquid level is measured by a conventional pulse-echo technique. A prototype sensor was tested successfully in a 2300-l water vessel at pressures up to about 37 MPa. A spectral analysis of the transmitted pulse reveals that the flexural, extensional, thickness-shear, and radial plate modes are excited into vibration, but none of these appears to be significantly affected by the pressurization of the liquid.

Leaf Potential Productivity at Different Canopy Levels in Densely-planted and Intermediately-thinned Apple Orchards

Directory of Open Access Journals (Sweden)

Ying SUN

2016-07-01

Full Text Available Most apple orchards in the apple production districts in China were densely planted with vigorous rootstocks during the 1980s. These orchards have suffered micro-environmental deterioration and loss of fruit quality because of the closed canopy. Modification of the densely-planted orchards is a priority in current apple production. Intermediate thinning is a basic technique used to transform densely-planted apple orchards in China. Our goal was to provide theoretical basis for studying the effect of thinning on the efficiency of photosynthetically active radiation (PAR, fruit quality, and yield. We measured leaf area, solar radiation, and leaf air exchange at different tree canopy levels and by fitting relevant photosynthetic models, vertical distribution characteristics of leaf photosynthetic potentials and PAR were analyzed in various levels within canopies in densely-planted and intermediately-thinned orchards. Intermediate thinning significantly improved the radiant environment inside the canopies. PAR distribution within the canopies in the intermediately-thinned orchard was better distributed than in the densely-planted orchards. The invalid space under 30.0% of relative photosynthetically active radiation (PARr was nearly zero in the intermediately-thinned orchard; but minimum PARr was 17.0% and the space under 0.30 of the relative height of the canopy was invalid for photosynthesis in the densely-planted orchard. The leaf photosynthetic efficiency in the intermediately-thinned orchard was improved. Photosynthetic rates (Pn at the middle and bottom levels of the canopy, respectively, were increased by 7.80% and 10.20% in the intermediately-thinned orchard. Leaf development, which influences photosynthetic potential, was closely related to the surrounding micro-environment, especially light. Leaf photosynthetic potentials were correlated with leaf nitrogen content (Nl and specific leaf weight (Ml at various levels of canopies. Compared

Transport, handling, and interim storage of intermediate-level transuranic waste at the INEL

International Nuclear Information System (INIS)

Metzger, J.C.; Snyder, A.M.

1977-09-01

The Idaho National Engineering Laboratory stores transuranic (TRU)-contaminated waste emitting significant amounts of beta-gamma radiation. This material is referred to as intermediate-level TRU waste. The Energy Research and Development Administration requires that this waste be stored retrievably during the interim before a Federal repository becomes operational. Waste form and packaging criteria for the eventual storage of this waste at a Federal repository, i.e., the Waste Isolation Pilot Plant (WIPP), have been tentatively established. The packaging and storage techniques now in use at the Idaho National Engineering Laboratory are compatible with these criteria and also meet the requirement that the waste containers remain in a readily-retrievable, contamination-free condition during the interim storage period. The Intermediate Level Transuranic Storage Facility (ILTSF) provides below-grade storage in steel pipe vaults for intermediate-level TRU waste prior to shipment to the WIPP. Designated waste generating facilities, operated for the Energy Research and Development Administration, use a variety of packaging and transportation methods to deliver this waste to the ILTSF. Transfer of the waste containers to the ILTSF storage vaults is accomplished using handling methods compatible with these waste packaging and transport methods

LOFT liquid level transducer application techniques and measurement uncertainty

International Nuclear Information System (INIS)

Batt, D.L.; Biladeau, G.L.; Goodrich, L.D.; Nightingale, C.M.

1979-01-01

A conductivity sensitive liquid level transducer (LLT) has been designed and used successfully for determining whether steam or water is present in the Loss-of-Fluid Tests (LOFT) performed by EG and G Idaho, Inc., at the Idaho National Engineering Laboratory. The presence of steam or water is determined by establishing a discriminator level which is set manually. A computer program establishes the presence or absence of water for each data point taken. In addition to liquid level, the LLT is used for reactor vessel mass and volume calculations. The uncertainty in the liquid level is essentially the spacing of the LLT electrodes

DISPOSAL OF LOW AND INTERMEDIATE LEVEL WASTE IN HUNGARY

Directory of Open Access Journals (Sweden)

Bálint Nős

2012-07-01

Full Text Available There are two operating facilities for management of low and intermediate level radioactive waste in Hungary. Experience with radioactive waste has a relatively long history and from its legacy some problems are to be solved, like the question of the historical waste in the Radioactive Waste Treatment and Disposal Facility (RWTDF. Beside the legacy problems the current waste arising from the Nuclear Power Plant (NPP has to be dealt with a safe and economically optimized way.

Liquidity, Financial Intermediation, and Monetary Policy in a New Monetarist Model

OpenAIRE

Williamson, Stephen

2009-01-01

A model of monetary exchange with private financial intermediation is constructed. Claims on financial intermedaries of two types are traded in transactions: circulating notes and deposits. There can be a role for the government in supplying liqudity, and level changes in the money supply accomplished through open market operations can be nonneutral. A Friedman rule is suboptimal, due to costs of maintaining the stock of currency. The model is used to address some issues related to current mo...

Establishing managerial requirements for low-and intermediate-level waste repository

International Nuclear Information System (INIS)

Chung, C. W.; Lee, Y. K.; Kim, H. T.; Park, W. J.; Suk, T. W.; Park, S. H.

2004-01-01

This paper reviews basic considerations for establishing managerial requirements on the domestic low-and intermediate-level radioactive waste repository and presents the corresponding draft requirements. The draft emphasizes their close linking with the related regulations, standards and safety assessment for the repository. It also proposes a desirable direction towards harmonizing together with the existing waste acceptance requirements for the repository

Generation, transport and conduct of radioactive wastes of low and intermediate level

International Nuclear Information System (INIS)

Lizcano, D.; Jimenez, J.

2005-01-01

The technological development of the last decades produced an increment in the application of the radiations in different human activities. The effect of it has been it the production of radioactive wastes of all the levels. In Mexico, some of the stages of the administration of the waste of low and intermediate level have not been completely resolved, as the case of the treatment and the final storage. In this work aspects of the generation, the transport and the administration of radioactive waste of low and intermediate level produced in the non energy applications from the radioactive materials to national level, indicating the generated average quantities, transported and tried annually by the National Institute of Nuclear Research (ININ). The main generators of wastes in Mexico, classified according to the activity in which the radioactive materials are used its are listed. Some of the main processes of treatment of radioactive wastes broadly applied in the world and those that are used at the moment in our country are also presented. (Author)

49 CFR Figure 2b to Subpart B of... - Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location...

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements-§§ 238.113 and 238.114 2B Figure 2B to... Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements—§§ 238.113 and...

49 CFR Figure 2a to Subpart B of... - Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location...

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements-§§ 238.113 and 238.114 2A Figure 2A to... Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements—§§ 238.113 and...

Low and intermediate level radioactive waste processing in plasma reactor

International Nuclear Information System (INIS)

Sauchyn, V.; Khvedchyn, I.; Van Oost, G.

2013-01-01

Methods of low and intermediate level radioactive waste processing comprise: cementation, bituminization, curing in polymer matrices, combustion and pyrolysis. All these methods are limited in their application in the field of chemical, morphological, and aggregate composition of material to be processed. The thermal plasma method is one of the universal methods of RAW processing. The use of electric-arc plasma with mean temperatures 2000 - 8000 K can effectively carry out the destruction of organic compounds into atoms and ions with very high speeds and high degree of conversion. Destruction of complex substances without oxygen leads to a decrease of the volume of exhaust gases and dimension of gas cleaning system. This paper presents the plasma reactor for thermal processing of low and intermediate level radioactive waste of mixed morphology. The equipment realizes plasma-pyrolytic conversion of wastes and results in a conditioned product in a single stage. As a result, the volume of conditioned waste is significantly reduced (more than 10 times). Waste is converted into an environmentally friendly form that suits long-term storage. The leaching rate of macro-components from the vitrified compound is less than 1.10 -7 g/(cm 2 .day). (authors)

Project study for the final disposal of intermediate toxicity radioactive wastes (low- and intermediate-level radioactive wastes) in geological formations

International Nuclear Information System (INIS)

1980-08-01

The present report aimed to show variations in the construction- and operation-technical feasibility of a final repository for low- and intermediate-level radioactive wastes. This report represents the summary of a project study given under contract by Nagra with a view to informing a broader public of the technical conception of a final repository. Particular stress was laid on the treatment of the individual system elements of a repository concept during the construction, operation and sealing phases. The essential basis for the project study is the origin, composition and quantity of the wastes to be disposed. The final repository described in this report is foreseen for the reception of the following low- and intermediate-level solid radioactive wastes: wastes from the nuclear power plant operation; secondary wastes from the reprocessing of nuclear fuels; wastes from the decommissioning of nuclear power plants; wastes from research, medicine and industry

Liquid hydrogen transfer pipes and level regulation systems

International Nuclear Information System (INIS)

Marquet, M.; Prugne, P.; Roubeau, P.

1961-01-01

Describes: 1) Transfer pipes - Plunging rods in liquid hydrogen Dewars; transfer pipes: knee-joint system for quick and accurate positioning of plunging Dewar rods; system's rods: combined valve and rod; valves are activated either by a bulb pressure or by a solenoid automatically or hand controlled. The latter allows intermittent filling. 2) Level regulating systems: Level bulbs: accurate to 1 or 4 m; maximum and minimum level bulbs: automatic control of the liquid hydrogen valve. (author) [fr

Survey of stores for conditioned intermediate and low level wastes in Europe

International Nuclear Information System (INIS)

1985-10-01

A survey has been conducted of eleven waste storage facilities in six countries. Wastes considered are intermediate and low level, conditioned for disposal. Civil engineering, handling facilities, container type, waste activities, doses to the public and to operators are considered. (author)

Measurement methodology for fulfilling of waste acceptance criteria for low and intermediate level radioactive waste in storages - 59016

International Nuclear Information System (INIS)

Sokcic-Kostic, M.; Langer, F.; Schultheis, R.

2012-01-01

Low and intermediate level radioactive waste must be sorted and treated before it can be sent to radioactive waste storage. The waste must fulfil an extensive amount of acceptance criteria (WAC) to guarantee a safe storage period. NUKEM Technologies has a broad experience with the building and management of radioactive waste treatment facilities and has developed methods and equipment to produce the waste packages and to gather all the required information. In this article we consider low and intermediate level radioactive waste excluding nuclear fuel material, even fresh fuel with low radiation. Only solid radioactive waste (RAW) will be considered. (Liquid RAW is usually processed and solidified before storage. Exception is the reprocessing of nuclear fuel.) Low and intermediate level radioactive waste has to be kept in storage facilities until isotopes are decayed sufficiently and the waste can be released. The storage has to fulfil certain conditions regarding the possible radiological impact and the possible chemical impact on the environment. With the inventory of nuclear waste characterised, the radiological impact can be estimated. RAW mainly originates from the operation of nuclear power plants. A small amount comes from reprocessing installations or from research entities. Chemical safety aspects are of qualitative nature, excluding substances in whole but not compared to limit values. Therefore they have minor influence on the storage conditions. Hereby corrosion and immobilisation of the waste play important roles. The storage concept assumes that the waste will be released if the radioactivity has decreased to an acceptable level. NUKEM Technologies has been specialised on collecting all data needed for the fulfilling of waste acceptance criteria (WAC). The classification as low or intermediate level waste is made on base of surface dose rate of the waste package as well as on the mass specific beta activity. Low level waste must not include isotopes

Projection to 2035 for the radioactive wastes of low and intermediate level in Mexico; Proyeccion al 2035 de los desechos radiactivos de nivel bajo e intermedio en Mexico

Energy Technology Data Exchange (ETDEWEB)

Paredes G, L.C. [ININ, Km. 36.5 Carr. Mexico-Toluca, 52045 Salazar, Estado de Mexico (Mexico); Sanchez U, S. [Comision Federal de Electricidad, Central Nucleoelectrica de Laguna Verde, Veracruz (Mexico)]. e-mail: lpg@nuclear.inin.mx

2004-07-01

It is necessary to establish in few years a definitive warehouse for the radioactive waste of low and intermediate level, generated in the country and to satisfy the necessities of their confinement in the next ones 50 to 80 years. Therefore, it is required to be considered those volumes produced annually, those stored at the present and those estimated to medium and long term. The results of the simulation of 4 cases are presented, considering the operation from the 2 nuclear power reactors to 40 and 60 years, the use of the technology of current treatment and the use of super compaction of solids, as well as the importance in the taking of decision of the methodology for the dismantlement of each reactor to the finish of their useful life. At the moment the Nuclear Power Plant of Laguna Verde, produces an average of 250 m{sup 3}/year of radioactive waste of low and intermediate level, constituted by solid dry wastes, humid solids and liquids. In the last 3 years, the power plant has reached an effectiveness of re utilization of effluents of 95%. On the other hand, in Mexico the non energetic applications of the radioisotopes, produce annually of the order of 20 m{sup 3}/year of solid wastes, 280 m{sup 3}/year of liquid wastes and 300 worn out radioactive sources. (Author)

Low and intermediate level waste repositories: public involvement aspects

International Nuclear Information System (INIS)

Ferreira, Vinicius V.M.; Mourao, Rogerio P.; Fleming, Peter M.; Soares, Wellington A.; Braga, Leticia T.P.; Santos, Rosana A.M.

2009-01-01

The nuclear energy acceptance creates several problems, and one of the most important is the disposal of the radioactive waste. International experiences show that not only environmental, radiological and technical questions have to be analyzed, but the public opinion about the project must be considered. The objective of this article is to summarize some public involvement aspects associated with low and intermediate level waste repositories. Experiences from USA, Canada, South Africa, Ukraine and other countries are studied and show the importance of the population in the site selection process for a repository. (author)

Separation of cesium from intermediate level liquid radioactive waste by solvent extraction with antioxidants

International Nuclear Information System (INIS)

Gulis, G.

1989-01-01

Antioxidants AO 2246, AO 4, AO 4K, AO 301 (Czechoslovakia) and NOCRAC 2246 (Japan) were tested as extracting agents for the separation of cesiium by solvent extraction with substituted phenols. The following effects on extraction were studied: pH of water phase, influence of diluent and of antioxidant concentration, extraction time, influence of salt content. The extraction of cesium from liquid radioactive waste was tested. The best results were obtained by NOCRAC 2246 in nitrobenzene, the extraction efficiency was 92.3% with pH 13.23. (author) 7 refs.; 5 figs.; 4 tabs

Impact of low-level BK polyomavirus viremia on intermediate-term renal allograft function.

Science.gov (United States)

Korth, Johannes; Widera, Marek; Dolff, Sebastian; Guberina, Hana; Bienholz, Anja; Brinkhoff, Alexandra; Anastasiou, Olympia Evdoxia; Kribben, Andreas; Dittmer, Ulf; Verheyen, Jens; Wilde, Benjamin; Witzke, Oliver

2018-02-01

BK polyomavirus (BKPyV)-associated nephropathy (PyVAN) is a significant cause of premature renal transplant failure. High-level BKPyV viremia is predictive for PyVAN; however, low-level BKPyV viremia does not necessarily exclude the presence of PyVAN. As data are limited regarding whether or not low-level BKPyV viremia has an effect on intermediate-term graft outcome, this study analyzes the impact of low-level BKPyV viremia on intermediate-term graft function and outcome compared with high-level viremia and non-viremic patients. All renal transplant patients received follow-up examinations at the Department of Nephrology, University Hospital Essen. Patients were screened for BKPyV viremia and stratified into three groups according to their maximum BKPyV load in serum (low-level viremia, high-level viremia, and no viremia). In 142 of 213 (67%) patients, BKPyV was never detected in serum; 42 of 213 (20%) patients were found positive for low-level viremia (≤10 4 copies/mL); and 29 of 213 (13%) patients showed high-level viremia (>10 4 copies/mL). No significant differences regarding transplant function and graft failure were observed between patients without BKPyV viremia (delta estimated glomerular filtration rate [eGFR] +0.1 mL/min [month 1 vs last visit at month 44]) and patients with low-level BKPyV viremia (delta eGFR -1.7 mL/min). In patients with high-level viremia, transplant function was significantly restricted (delta eGFR -6.5 mL/min) compared with low-level viremia until the last visit at 44 ± 9.7 months after transplantation. Although the graft function and graft loss were worse in the high-level viremia group compared with no viremia (eGFR 37 vs 45 mL/min), the difference was not significant. High-level viremia was associated with impaired graft function. In contrast, low-level BKPyV viremia had no significant impact on intermediate-term graft function. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Treatment of ORNL liquid low-level waste

International Nuclear Information System (INIS)

Berry, J.B.; Brown, C.H. Jr.; Fowler, V.L.; Robinson, S.M.

1988-01-01

Discontinuation of the hydrofracture disposal method at Oak Ridge National Laboratory (ORNL) has caused intensive efforts to reduce liquid waste generation. Improving the treatment of slightly radioactive liquid waste, called process waste, has reduced the volume of the resulting contaminated liquid radioactive waste effluent by 66%. Proposed processing improvements could eliminate the contaminated liquid effluent and reduce solid low-level waste by an additional one-third. The improved process meets stringent discharge limits for radionuclides. Discharge limits for radionuclides are expected to be enforced at the outfall of the treatment plant to a creek; currently, limits are enforced at the reservation boundary. Plant discharge is monitored according to the National Pollutant Discharge Elimination System (NPDES) permit for ORNL. 1 ref., 4 figs., 2 tabs

Frequency and Wavevector Dependence of the Atomic Level Stress-Stress Correlation Function in a Model Supercooled Liquid

Science.gov (United States)

Levashov, Valentin A.; Morris, James R.; Egami, Takeshi

2012-02-01

Temporal and spatial correlations among the local atomic level shear stresses were studied for a model liquid iron by molecular dynamics simulation [PRL 106,115703]. Integration over time and space of the shear stress correlation function F(r,t) yields viscosity via Green-Kubo relation. The stress correlation function in time and space F(r,t) was Fourier transformed to study the dependence on frequency, E, and wave vector, Q. The results, F(Q,E), showed damped shear stress waves propagating in the liquid for small Q at high and low temperatures. We also observed additional diffuse feature that appears as temperature is reduced below crossover temperature of potential energy landscape at relatively low frequencies at small Q. We suggest that this additional feature might be related to dynamic heterogeneity and boson peaks. We also discuss a relation between the time-scale of the stress-stress correlation function and the alpha-relaxation time of the intermediate self-scattering function S(Q,E).

Aube storage center for short-lived low- and intermediate-level wastes. Annual report 2008

International Nuclear Information System (INIS)

2009-06-01

The National Radioactive Waste Management Agency (Andra), was established by the December 1991 Waste Act as a public body in charge of the long-term management of all radioactive waste, under the supervision of the Ministry of Ecology, Energy, Sustainable Development and the Sea (formerly the Ministry of Industry and the Ministry of Environment), and the Ministry of Research. The Andra operates two storage centers in the Aube region (France): the center for short-lived low- and intermediate-level wastes, and the center for very-low-level radioactive wastes. This document is the 2008 activity report of the center for short-lived low- and intermediate-level wastes. It presents a review of the activities of the center: presentation of the installations, safety and radiation protection, events or incidents, environmental monitoring, wastes management, public information

New Type Multielectrode Capacitance Sensor for Liquid Level

Energy Technology Data Exchange (ETDEWEB)

Zhao, Y R [China University of Petroleum (Huadong), Qingdao (China); Shi, A P [Shandong University of Science and Technology, Qingdao (China); Chen, G Q [Shandong University of Science and Technology, Qingdao (China); Chang, Y Y [Shandong University of Science and Technology, Qingdao (China); Hang, Z [Shandong University of Science and Technology, Qingdao (China); Liu, B M [Binzhou University, Binzhou (China)

2006-10-15

This paper introduces the design of a new type multielectrode capacitance sensor for liquid level. The system regards electric field sensor MC33794 as the core and applies microcontroller MC9S12DJ128 to realize intelligent liquid level monitoring system, which overcomes the disadvantages of the traditional capacitance sensor, improves on the anti-jamming ability and the measurement precision and simplifies the system structure. Finally, the paper sums up the design of the system.

An Applied Study of the Storage for Old Intermediate Level Waste at the Studsvik Site

International Nuclear Information System (INIS)

Sjoeblom, Rolf; Lindskog, Staffan

2004-02-01

The Storage for Old Intermediate Level Waste (SOILW) at Studsvik has been used for interim storage of intermediate and high level radioactive waste from various activities at the Studsvik site including post irradiation investigations. The SOILW facility was in operation during the years 1961 - 1984. The waste was stored in tube positions in concrete blocks and in concrete vaults. In some instances, radioactive debris and liquid has contaminated the storage positions as well as the underlying ventilation space. The primary purpose of the present work is to improve and extend the present knowledge basis for cost estimates for decommissioning, with the ACSF facility as an example. The main objective has been to explore the possibilities to improve the reliability and accuracy of capital budgeting for decommissioning costs at SOILW. In this study, the present international status of decommissioning, planning and cost estimation has been compiled. The various relevant guidance documents of the IAEA are also compiled, and their emphasis on the necessity of radiological and other surveying as well as technical planning and method selection is reiterated. Cost calculation schemes for new plants and for decommissioning are compiled. It is emphasized that the calculations should be carried out differently at different stages. At the early stages of decommissioning, there should be more emphasis on comparison, and at later stages the emphasis should be more oriented towards summation. The error/uncertainty in a cost calculation is strongly dependent on the selection of methodology, which, in turn, is strongly dependent on the radiological condition. The magnitude of the level of uncertainty has been illustrated by the example of concrete surface removal, and advice is provided on how to identify alternative measures that will enable more sure decisions. An example is also given on a rather similar decontamination and dismantling involving highly contaminated tubes in a

UKAEA contract no. 3: miscellaneous solid, liquid and gaseous wastes

International Nuclear Information System (INIS)

Partridge, B.A.

1984-12-01

This document reports work carried out in 1982/83 on the following topics concerned with the treatment and disposal of intermediate level wastes: flowsheeting; dewatering low and medium level radioactive wastes; applications of ultrafiltration in the treatment of radioactive liquid wastes; ion exchange processes; electrical processes for the treatment of medium active liquid wastes; chemical conversion of Zircaloy cladding to oxide; fast reactor fuel element cladding; dissolver residues; fuel cladding and ion exchanger immobilisation - radioactive trials; thermal techniques; development and assessment of medium level waste forms. (U.K.)

Practices and developments in the management of low and intermediate level radioactive waste in Sweden

International Nuclear Information System (INIS)

Hultgren, Aa.

1983-06-01

In the Swedish nuclear power program ten reactors are in operation and two more under construction. About 100000 m 3 of low and intermediate level radioactive waste will be produced from the operation of these reactors until the year 2010 and about 150000 m 3 from their decommissioning. All burnable radioactive wastes are sent to the Studsvik incineration plant for incineration. Spent resins are incorporated into cement or bitumen. The volume of non-combustible solid waste is reduced by compaction where possible. At the Studsvik research centre a substantial program for improved management of accumulated and future radioactive waste is at the beginning of its implementation. This includes advanced treatment and intermediate storage in a rock cavity. An R and D program on volume reduction of spent resins has reached the point of process verification and equipment design. All low and intermediate radioactive waste will be disposed in a rock cavity planned for commissioning by 1988. The paper reviews actual management experience and development efforts for low and intermediate level radioactive waste in Sweden. Contribution to the Seminar on the Management of Radioactive Waste, Taipei, Taiwan, 25-26 June, 1983. (Author)

A high Tc superconducting liquid nitrogen level sensor

International Nuclear Information System (INIS)

Jin, J. X.; Liu, H. K.; Dou, S. X.; Grantham, C.; Beer, J.

1996-01-01

Full text: The dramatic resistance change in the superconducting-normal transition temperature range enables a high T c superconductor to be considered for designing a liquid nitrogen level sensor. A (Bi,Pb) 2 Sr 2 Ca 2 Cu 3 O 10+x Ag clad superconducting wire is selected and tested as a continuous liquid nitrogen level sensor to investigate the possibility for this application. The (Bi,Pb) 2 Sr 2 Ca 2 Cu 3 O 10+x Ag clad superconducting wire has approximately 110 K critical temperature, with more flexible and stable properties compared with bulk shape ceramic high T c superconductors. The voltage drops across the sensor are tested with different immersion lengths in liquid nitrogen. The accuracy of the HTS sensor is analysed with its dR/dT in the superconducting-normal transition range. The voltage signal is sensitive to liquid nitrogen level change, and this signal can be optimized by controlling the transport current. The problems of the Ag clad superconductor are that the Ag sheath thermal conductivity is very high, and the sensor normal resistance is low. These are the main disadvantages for using such a wire as a continuous level sensor. However, a satisfactory accuracy can be achieved by control of the transport current. A different configuration of the wire sensor is also designed to avoid this thermal influence

Light Path Model of Fiber Optic Liquid Level Sensor Considering Residual Liquid Film on the Wall

Directory of Open Access Journals (Sweden)

Zhijun Zhang

2015-01-01

Full Text Available The working principle of the refractive-type fiber optic liquid level sensor is analyzed in detail based on the light refraction principle. The optic path models are developed in consideration of common simplification and the residual liquid film on the glass tube wall. The calculating formulae for the model are derived, constraint conditions are obtained, influencing factors are discussed, and the scopes and skills of application are analyzed through instance simulations. The research results are useful in directing the correct usage of the fiber optic liquid level sensor, especially in special cases, such as those involving viscous liquid in the glass tube monitoring.

Application of remote sensing technique to site selection for low and intermediate level radioactive waste

International Nuclear Information System (INIS)

Chen Zhangru; Jin Yuanxin; Liu Yuemiao; Hou Dewen

2001-01-01

Based on the relative criteria of selection of disposal site for low and intermediate level radioactive waste, the social-economic conditions, landform, morphologic properties, regional geological stability, hydrogeological and engineering geological characters of adjacent area of Anhui, Zhejiang and Jiangsu provinces were investigated. The geological interpretation of thematic mapper images, field reconnaissance and data analysis were conducted during the research work. The results show that three areas in the west part of Zhejiang Province were recommended as potential site for disposal of low and intermediate level radioactive waste. They are Bajiaotang area, Tiebanchong area and Changxing-Guangde-Anji nabes

Ultrasonic level indicator for liquids and its application

International Nuclear Information System (INIS)

Kanngiesser, P.

1976-01-01

Ultrasonic level indicator for liquids where a piezo-element is used to reverse the piezoelectric effect may be applied in a more versatile way if the indicator is provided with a reflector. It becomes less susceptible to faults and may be used for all liquids, including liquid metals. The piezo-element may then be used at the same time as receiver for ultrasonic waves emitted previously and, in that case, echoed back by the refelctor. (UWI) [de

Aube storage centre for short-lived low- and intermediate-level wastes. Annual report 2009

International Nuclear Information System (INIS)

2010-06-01

The National Radioactive Waste Management Agency (Andra), was established by the December 1991 Waste Act as a public body in charge of the long-term management of all radioactive waste, under the supervision of the Ministry of Ecology, Energy, Sustainable Development and the Sea (formerly the Ministry of Industry and the Ministry of Environment), and the Ministry of Research. The Andra operates two storage centers in the Aube region (France): the center for short-lived low- and intermediate-level wastes, and the center for very-low-level radioactive wastes. This document is the 2009 activity report of the center for short-lived low- and intermediate-level wastes. It presents a review of the activities of the center: presentation of the installations, safety and radiation protection, events or incidents, environmental monitoring, wastes management, public information, opinion of the Health and safety Committee (CHSCT)

Aube storage center for short-lived low- and intermediate-level wastes. Annual report 2010

International Nuclear Information System (INIS)

2011-06-01

The National Radioactive Waste Management Agency (Andra), was established by the December 1991 Waste Act as a public body in charge of the long-term management of all radioactive waste, under the supervision of the Ministry of Ecology, Energy, Sustainable Development and the Sea (formerly the Ministry of Industry and the Ministry of Environment), and the Ministry of Research. The Andra operates two storage centers in the Aube region (France): the center for short-lived low- and intermediate-level wastes, and the center for very-low-level radioactive wastes. This document is the 2010 activity report of the center for short-lived low- and intermediate-level wastes. It presents a review of the activities of the center: presentation of the installations, safety and radiation protection, events or incidents, environmental monitoring, wastes management, public information, recommendations of the Health and safety Committee (CHSCT)

Commissioning of the XENON1T liquid level measurement system

Energy Technology Data Exchange (ETDEWEB)

Geis, Christopher [Institut fuer Physik, Johannes Gutenberg-Universitaet, Mainz (Germany)

2016-07-01

Two-phase xenon time projection chambers (TPCs) have been operated very successfully in direct detection experiments for dark matter. This kind of detector uses liquid xenon as the sensitive target and is operated in two-phase (liquid/gas) mode, where the liquid level needs to be monitored and controlled with sub-millimeter precision. We present the installation, commissioning and first measurement data of two kinds of level meters operated in the XENON1T TPC: short level meters are three-plated capacitors measuring the level of the liquid-gas interface with a measurement range h∼5 mm and a resolution of ΔC/h∼1 pF/mm. The long level meters are cylindrical double-walled capacitors, measuring the overall filling level of the XENON1T TPC at a measurement range of h=1.4 m and a resolution of ΔC/h∼0.1 pF/mm. Further, we present the design and programming of the readout electronic based on the UTI chip by Smartec, which allows to read all six levelmeters simultaneously.

Oxidative demethylation of lanosterol in cholesterol biosynthesis: accumulation of sterol intermediates

International Nuclear Information System (INIS)

Shafiee, A.; Trzaskos, J.M.; Paik, Y.K.; Gaylor, J.L.

1986-01-01

With [ 3 H-24,25]-dihydrolanosterol as substrate, large-scale metabolic formation of intermediates of lanosterol demethylation was carried out to identify all compounds in the metabolic process. Utilizing knowledge of electron transport of lanosterol demethylation, we interrupted the demethylation reaction allowing accumulation and confirmation of the structure of the oxygenated intermediates lanost-8-en-3 beta,32-diol and 3 beta-hydroxylanost-8-en-32-al, as well as the demethylation product 4,4-dimethyl-cholesta-8,14-dien-3 beta-ol. Further metabolism of the delta 8.14-diene intermediate to a single product 4,4-dimethyl-cholest-8-en-3 beta-ol occurs under interruption conditions in the presence of 0.5 mM CN-1. With authentic compounds, each intermediate has been rigorously characterized by high performance liquid chromatography and gas-liquid chromatography plus mass spectral analysis of isolated and derivatized sterols. Intermediates that accumulated in greater abundance were further characterized by ultraviolet, 1 H-NMR, and infrared spectroscopy of the isolated sterols

Engineering design study for storage and disposal of intermediate level waste

Energy Technology Data Exchange (ETDEWEB)

Griffin, J R; Hackney, S; Richardson, J A; Heafield, W

1982-11-01

A conceptual design study is presented which covers both the storage and disposal of intermediate level waste; repositories in several rock formations are considered at a 300m depth. A total system is proposed including an engineered trench for ..beta gamma.. waste, emplacement systems and off site transportation. Safety during the emplacement phase and the radiological effects of human intrusion and geological catastrophies are considered.

Electrical processes for liquid waste treatment

International Nuclear Information System (INIS)

Turner, A.D.; Bridger, N.J.; Junkison, A.R.; Pottinger, J.S.

1987-08-01

This report describes the development of electrical techniques for the treatment of liquid waste streams. Part I is concerned with solid/liquid separation and the demonstration of the electrokinetic thickening of flocs at inorganic membranes suitable for intermediate-level wastes and electrochemical cleaning of stainless steel microfilters and graphite ultrafilters. Part II describes work on the development of electrochemical ion exchange, particularly the use of inorganic absorption media and polarity reversal to enhance system selectivity. Work on the adsorption and desorption of plutonium in acid nitrate solution at various electrode materials is also included. (author)

Concrete conditioners for low-intermediate level nuclear wastes

International Nuclear Information System (INIS)

Roehl, J.L.; Lorentz, R.G.; Franzen, H.R.

1986-01-01

The conditioning of low-intermediate level radioactive waste disposal, in Brazil, with concrete packages designed in such way that, in spite of being destined to receive compacted materials in long term sub-surface disposal, they may also be able to attend other storage or disposal necessities, is analysed. A design of a reinforced concrete package with a net volume of 360 l and, with compatible diameter to contain compacted 200 l drums, was developed. A study on compactation of 200 l steel packages is done. A pressure of 30.000 KN for compacting these 200 l drums was adapted, and two series of tests to verify the pressure volume reduction ratio and, the final dimensions and density of the compacted elements, was executed. (Author) [pt

Nirex plans for low and intermediate level waste

International Nuclear Information System (INIS)

Mathieson, J.

1995-01-01

Two main events have dominated Nirex's recent history: the Radioactive Waste Review and the Company's plans to build a Rock Characterisation facility at its investigation site near Sellafield in Cumbria. The outcome of the former was announced in a White Paper in July 1995. Decisions on the RCF are subject to a public inquiry starting in September 1995. Given a successful result and confirmation that the site could meet the safety target, a deep repository for intermediate and some low level waste could be available by 2011 or thereabouts. As financing of Nirex's activities is in line with the ''polluter pays'' principle, the Company is aiming to deliver a cost-effective disposal system which complies fully with the stringent safety requirements placed on it. (author)

Tobacco-Specific Nitrosamines in Electronic Cigarettes: Comparison between Liquid and Aerosol Levels

Directory of Open Access Journals (Sweden)

Konstantinos E. Farsalinos

2015-07-01

Full Text Available Introduction: Although electronic cigarette (EC liquids contain low levels of tobacco-specific nitrosamines (TSNAs, studies evaluating the levels emitted to the aerosol are scarce. The purpose of this study was to compare the levels of TSNAs between liquids and generated aerosol. Methods: Three EC liquids were obtained from the market. An additional (spiked sample was prepared by adding known amounts of standard TSNAs solutions to one of the obtained liquids. N-nitrosonornicotine (NNN, N-nitrosoanatabine (NAT, N-nitrosoanabasine (NAB and 4-(methylnitrosamino1-(3-pyridyl-1-butanone (NNK were measured. Three 100-puff sets from each liquid were trapped in filter pads and were subsequently analyzed for the presence of TSNAs. The expected levels of TSNAs (calculated based on the liquid consumption were compared with the measured levels in the aerosol. Results: Only NAB was found at trace levels in two commercial liquids (1.2 and 2.3 ng/g, while the third contained 1.5 ng/g NAB and 7.7 ng/g NNN. The 100-puff sets resulted in 336–515 mg liquid consumption, with no TSNAs being detected in the aerosol. The spiked sample contained 42.0–53.9 ng/g of each of the TSNAs. All TSNAs were detected in the aerosol with the measured levels being statistically similar to the expected amounts. A significant correlation between expected and measured levels of TSNAs in the aerosol was found (r = 0.83, p < 0.001. Conclusion: The findings of this study show that exposure of EC users to TSNAs can be accurately assessed based on the levels present in the liquid, without the need to analyze the aerosol.

Colloidal gas-liquid condensation of polystyrene latex particles with intermediate kappa a values (5 to 160, a > kappa(-1)).

Science.gov (United States)

Ishikawa, Masamichi; Kitano, Ryota

2010-02-16

Polystyrene latex particles showed gas-liquid condensation under the conditions of large particle radius (a > kappa(-1)) and intermediate kappa a, where kappa is the Debye-Hückel parameter and a is the particle radius. The particles were dissolved in deionized water containing ethanol from 0 to 77 vol %, settled to the bottom of the glass plate within 1 h, and then laterally moved toward the center of a cell over a 20 h period in reaching a state of equilibrium condensation. All of the suspensions that were 1 and 3 microm in diameter and 0.01-0.20 vol % in concentration realized similar gas-liquid condensation with clear gas-liquid boundaries. In 50 vol % ethanol solvent, additional ethanol was added to enhance the sedimentation force so as to restrict the particles in a monoparticle layer thickness. The coexistence of gas-liquid-solid (crystalline solid) was microscopically recognized from the periphery to the center of the condensates. A phase diagram of the gas-liquid condensation was created as a function of KCl concentration at a particle diameter of 3 microm, 0.10 vol % concentration, and 50:50 water/ethanol solvent at room temperature. The miscibility gap was observed in the concentration range from 1 to 250 microM. There was an upper limit of salt concentration where the phase separation disappeared, showing nearly critical behavior of macroscopic density fluctuation from 250 microM to 1 mM. These results add new experimental evidence to the existence of colloidal gas-liquid condensation and specify conditions of like-charge attraction between particles.

Return and Liquidity Relationships on Market and Accounting Levels in Brazil

Directory of Open Access Journals (Sweden)

Fernanda Finotti Cordeiro Perobelli

2016-08-01

Full Text Available ABSTRACT This article discusses profitability-liquidity relationships on accounting and market levels for 872 shares of publicly-traded Brazilian companies, observed between 1994 and 2013. On the market level, the assumption is that share liquidity is able to reduce some of the risks incurred by investors, making them more willing to pay a higher price for liquid shares, which would lower expected market returns. On the accounting level, the basic hypothesis argues that a firm's holding more liquid assets is related to a conservative investment policy, possibly reducing accounting returns for shareholders. Under the assumption of financial constraint, however, more accounting liquidity would allow positive net present value investments to be carried out, increasing future accounting returns, which would positively affect market liquidity and share prices in an efficient market, resulting in a lower market risk/expected return premium. Under the assumption of no financial constraint, however, more accounting liquidity would only represent a carry cost, compromising future accounting returns, which would adversely affect market liquidity and share prices and result in a higher market risk/expected return premium. Among the hypotheses, the presence of a negative market liquidity premium was verified in Brazil, with shares that traded more exhibiting a higher expected market return. On the margins of the major theories on the subject, only two negative relationships between excess accounting liquidity and market liquidity and accounting return, supporting the carry cost assumption for financially unconstrained firms, were verified. In terms of this paper's contributions, there is the analysis, unprecedented in Brazil as far as is known, of the relationship between liquidity and return on market and accounting levels, considering the financial constraint hypothesis to which the firms are subject.

Continuous Hydrolysis and Liquid–Liquid Phase Separation of an Active Pharmaceutical Ingredient Intermediate Using a Miniscale Hydrophobic Membrane Separator

DEFF Research Database (Denmark)

Cervera Padrell, Albert Emili; Morthensen, Sofie Thage; Lewandowski, Daniel Jacob

2012-01-01

Continuous hydrolysis of an active pharmaceutical ingredient intermediate, and subsequent liquid–liquid (L-L) separation of the resulting organic and aqueous phases, have been achieved using a simple PTFE tube reactor connected to a miniscale hydrophobic membrane separator. An alkoxide product......, obtained in continuous mode by a Grignard reaction in THF, reacted with acidic water to produce partially miscible organic and aqueous phases containing Mg salts. Despite the partial THF–water miscibility, the two phases could be separated at total flow rates up to 40 mL/min at different flow ratios, using...

Return and Liquidity Relationships on Market and Accounting Levels in Brazil

OpenAIRE

Perobelli,Fernanda Finotti Cordeiro; Famá,Rubens; Sacramento,Luiz Claudio

2016-01-01

ABSTRACT This article discusses profitability-liquidity relationships on accounting and market levels for 872 shares of publicly-traded Brazilian companies, observed between 1994 and 2013. On the market level, the assumption is that share liquidity is able to reduce some of the risks incurred by investors, making them more willing to pay a higher price for liquid shares, which would lower expected market returns. On the accounting level, the basic hypothesis argues that a firm's holding more ...

Cement-based processes for the immobilization of intermediate level radioactive waste

International Nuclear Information System (INIS)

Brown, D.J.; Lee, D.J.; Price, M.S.T.; Smith, D.L.G.

1985-01-01

Increasing attention is being paid to the use of cement-based materials for the immobilisation of intermediate level wastes. Various cementitious materials are surveyed and the use of blast furnace slag is shown to be advantageous. The properties of cemented wastes are surveyed both during processing and as solid products. The application of Winfrith Cementation Laboratory technology to plant and flowsheet development for Winfrith Reactor sludge immobilisation is described. (author)

Development of a test system for high level liquid waste partitioning

Directory of Open Access Journals (Sweden)

Duan Wu H.

2015-01-01

Full Text Available The partitioning and transmutation strategy has increasingly attracted interest for the safe treatment and disposal of high level liquid waste, in which the partitioning of high level liquid waste is one of the critical technical issues. An improved total partitioning process, including a tri-alkylphosphine oxide process for the removal of actinides, a crown ether strontium extraction process for the removal of strontium, and a calixcrown ether cesium extraction process for the removal of cesium, has been developed to treat Chinese high level liquid waste. A test system containing 72-stage 10-mm-diam annular centrifugal contactors, a remote sampling system, a rotor speed acquisition-monitoring system, a feeding system, and a video camera-surveillance system was successfully developed to carry out the hot test for verifying the improved total partitioning process. The test system has been successfully used in a 160 hour hot test using genuine high level liquid waste. During the hot test, the test system was stable, which demonstrated it was reliable for the hot test of the high level liquid waste partitioning.

Cement encapsulation of low-level waste liquids. Final report

International Nuclear Information System (INIS)

Baker, M.N.; Houston, H.M.

1999-01-01

Pretreatment of liquid high-level radioactive waste at the West Valley Demonstration Project (WVDP) was essential to ensuring the success of high-level waste (HLW) vitrification. By chemically separating the HLW from liquid waste, it was possible to achieve a significant reduction in the volume of HLW to be vitrified. In addition, pretreatment made it possible to remove sulfates, which posed several processing problems, from the HLW before vitrification took place

Instructions for 104-SX liquid level measurement field tests

International Nuclear Information System (INIS)

Webb, R.H.

1994-01-01

This document provides detailed instructions for field testing a suggested solution of inserting a liner inside the 104-SX failed Liquid Observation Well to gain access for making temporary Liquid Level Measurement until a permanent solution has been provided

Process design of a new injection method of liquid CO2 at the intermediate depths in the ocean using a static mixer

International Nuclear Information System (INIS)

Tajima, Hideo; Yamasaki, Akihiro; Kiyono, Fumio

2005-01-01

Process design for a new injection method of liquid CO 2 using a static mixer was conducted based on laboratory experimental results on the formation process of liquid CO 2 drops covered with hydrate film by a Kenics-type static mixer, and numerical simulation of the liquid CO 2 drops at 500 and 1500 m. The Sauter Mean Diameter (SMD) of the liquid CO 2 drops covered with hydrate film was dramatically decreased with the use of the static mixer; empirical equations were obtained for the SMD, and also the maximum and minimum diameters of the liquid CO 2 drops for a given flow velocity (Weber number, We). The ascending and dissolving behavior of a liquid CO 2 drop with hydrate released in the ocean at an intermediate depth was numerically simulated, and the maximum drop diameter to avoid evaporation of the drop before complete dissolution was estimated. Based on these results, scaling up of the static mixer was conducted by assuming a disposal process of CO 2 emitted from a 100-MW thermal power plant, and the mixer diameter was determined as a function of the given SMD. Moreover, the power consumption of the static mixer was evaluated and found to be almost negligible. (author)

Geological factors of disposal site selection for low-and intermediate-level solid radwastes in China

International Nuclear Information System (INIS)

Chen Zhangru

1993-01-01

For disposal of low- and intermediate-level solid radioactive wastes, shallow-ground disposal can provide adequate isolation of waste from human for a fairly long period of time. The objective of disposal site selection is to ensure that the natural properties of the site together with the engineered barrier site shall provide adequate isolation of radionuclides from the human beings and environment, so the whole disposal system can keep the radiological impact within an acceptable level. Since the early 1980's, complying with the national standards and the expert's conception as well as the related IAEA Criteria, geological selection of disposal sites for low-and intermediate-level solid radwastes has been carried out in East China, South China, Northwest China and Southwest China separately. Finally, 5 candidate sites were recommended to the CNNC

Structural, dynamic, electronic, and vibrational properties of flexible, intermediate, and stressed rigid As-Se glasses and liquids from first principles molecular dynamics

International Nuclear Information System (INIS)

Bauchy, M.; Kachmar, A.; Micoulaut, M.

2014-01-01

The structural, vibrational, electronic, and dynamic properties of amorphous and liquid As x Se 1-x (0.10 intermediate phase in these glassy networks, observed at 0.27 liquid phase, thereby linking structural and dynamical atomic-scale fingerprints for the onset of rigidity within the network, while also providing a much more complex picture than the one derived from mean-field approaches of stiffness transitions

Ferrofluids in liquid crystalline systems

International Nuclear Information System (INIS)

Figueiredo Neto, A.M.; Liebert, L.

1989-08-01

It is a well-known fact that intermediate or mesomorphic phase may exist between the crystalline and the isotropic liquid phases. The symmetry properties of these mesophases are intermediate between those of a crystal and a liquid. In this paper, some aspects of the use of ferrofluids in thermotropic and lyotropic systems are studied both the experimental difficulties as well as the fundamental phypical phenomena involved. (A.C.A.S.) [pt

Liquid metal cooled fast breeder nuclear reactors

International Nuclear Information System (INIS)

Durston, J.G.

1976-01-01

It is stated that in a liquid metal cooled fast breeder reactor wherein the core, intermediate heat exchangers and liquid metal pumps are immersed in a pool of coolant such as Na, the intermediate heat exchangers are suspended from the roof, and ducting is provided in the form of a core tank or shroud interconnected with 'pods' housing the intermediate exchangers for directing coolant from the core over the heat exchanger tubes and thence back to the main pool of liquid metal. Seals are provided between the intermediate heat exchanger shells and the walls of their 'pods' to prevent liquid metal flow by-passing the heat exchanger tube bundles. As the heat exchangers must be withdrawable for servicing, and because linear differential thermal expansion of the heat exchanger and its 'pod' must be accommodated the seals hitherto have been of the sliding kind, generally known as 'piston ring type seals'. These present several disadvantages; for example sealing is not absolute, and the metal to metal seal gives rise to wear and fretting by rubbing and vibration. This could lead to seizure or jamming by the deposition of impurities in the coolant. Another difficulty arises in the need to accommodate lateral thermal expansion of the ducting, including the core tank and 'pods'. Hitherto some expansion has been allowed for by the use of expansible bellow pairs in the interconnections, or alternatively by allowing local deformations of the core tank 'pods'. Such bellows must be very flexible and hence constitute a weak section of the ducting, and local deformations give rise to high stress levels that could lead to premature failure. The arrangement described seeks to overcome these difficulties by use of a gas pocket trapping means to effect a seal against vertical liquid flow between the heat exchanger shell and the wall of the heat exchanger housing. Full details of the arrangement are described. (U.K.)

Colloids related to low level and intermediate level waste

International Nuclear Information System (INIS)

Ramsay, J.D.F.; Russell, P.J.; Avery, R.G.

1991-03-01

A comprehensive investigation has been undertaken to improve the understanding of the potential role of colloids in the context of disposal and storage of low and intermediate level waste immobilised in cement. Several topics have been investigated using a wide range of advanced physico-chemical and analytical techniques. These include: (a) the study of formation and characteristics of colloids in cement leachates, (b) the effects of the near-field aqueous chemistry on the characteristics of colloids in repository environments, (c) colloid sorption behaviour, (d) interactions of near-field materials with leachates, and (e) preliminary assessment of colloid migration behaviour. It has been shown that the generation of colloids in cement leachates can arise from a process of nucleation and growth leading to an amorphous phase which is predominantly calcium silicate hydrate. Such colloidal material has a capacity for association with polyvalent rare earths and actinides and these may be significant in the source term and processes involving radionuclide retention in the near field. It has also been shown that the near-field aqueous chemistry (pH, Ca 2+ concentration) has a marked effect on colloid behaviour (deposition and stability). A mechanistic approach to predict colloid sorption affinity has been developed which highlights the importance of colloid characteristics and the nature of the ionic species. (author)

Disposal approach for long-lived low and intermediate-level radioactive waste

International Nuclear Information System (INIS)

Park, Jin Beak; Park, Joo Wan; Kim, Chang Lak

2005-01-01

There certainly exists the radioactive inventory that exceeds the waste acceptance criteria for final disposal of the low and intermediate-level radioactive waste. In this paper, current disposal status of the long-lived radioactive waste in several nations are summarized and the basic procedures for disposal approach are suggested. With this suggestion, intensive discussion and research activities can hopefully be launched to set down the possible resolutions to dispose of the long-lived radioactive waste

Types of organic materials present in BNFL intermediate level waste streams

International Nuclear Information System (INIS)

Barlow, P.

1988-01-01

This presentation lists the constituents present in BNFL intermediate-level radioactive wastes. The inorganic and organic components are listed and there is a detailed analysis of the plutonium contaminated materials in terms of proportion of combustible and non-combustible content, up to the year 2000. A description of the Waste Treatment Complex at Sellafield is presented. The research programme for leach testing, sorption and solubility testing and decomposition of organic matter was outlined. (U.K.)

Questionnaire established for the Brazilian inventory of low and intermediate level radioactive waste

Energy Technology Data Exchange (ETDEWEB)

Marumo, Julio T., E-mail: jtmarumo@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Silva, Fabio; Pinto, Antonio Juscelino, E-mail: silvaf@cdtn.br, E-mail: ajp@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Taveira, Gerson L.S., E-mail: gersonluizst@gmail.com [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil). Engenharia de Producao Civil

2015-07-01

The Nuclear Technology Development Center (CDTN), an institute of Brazilian National Commission of Nuclear Energy (CNEN), is responsible for the technical coordination of the Brazilian Repository Project (RBMN), for Low and Intermediate Level Radioactive Wastes. To establish the inventory of the low and intermediate radioactive level waste to be disposed in the national Repository, a questionnaire was elaborated to be filled on line, via WEB, exclusively to registered users, which involved CNEN's institutes, ELETRONUCLEAR, INB and CTMSP. Based on all standardized information received from questionnaires, an easy use database to inventory the radioactive waste was created in Microsoft Access® that supported the calculation of the volume of radioactive waste treated and non-treated, stored and generated presently in Brazil. In addition, from this database it will be possible to establish some disposal procedures and the necessary area of construction. The objective of this work is to present this database and some general information about the radwastes in Brazil. (author)

Questionnaire established for the Brazilian inventory of low and intermediate level radioactive waste

International Nuclear Information System (INIS)

Marumo, Julio T.; Silva, Fabio; Pinto, Antonio Juscelino; Taveira, Gerson L.S.

2015-01-01

The Nuclear Technology Development Center (CDTN), an institute of Brazilian National Commission of Nuclear Energy (CNEN), is responsible for the technical coordination of the Brazilian Repository Project (RBMN), for Low and Intermediate Level Radioactive Wastes. To establish the inventory of the low and intermediate radioactive level waste to be disposed in the national Repository, a questionnaire was elaborated to be filled on line, via WEB, exclusively to registered users, which involved CNEN's institutes, ELETRONUCLEAR, INB and CTMSP. Based on all standardized information received from questionnaires, an easy use database to inventory the radioactive waste was created in Microsoft Access® that supported the calculation of the volume of radioactive waste treated and non-treated, stored and generated presently in Brazil. In addition, from this database it will be possible to establish some disposal procedures and the necessary area of construction. The objective of this work is to present this database and some general information about the radwastes in Brazil. (author)

Radiation exposure rate and liquid level measurement inside a high level liquid waste (HLLW) storage tank

International Nuclear Information System (INIS)

Sur, B.; Yue, S.; Thekkevarriam, A.

2007-01-01

An instrument based on an inexpensive, small silicon diode has been developed and used to measure, for the first time, the gamma radiation exposure rate profile inside a 6.4 mm diameter reentrant thermo-well tube, immersed in the highly radioactive liquid solution in an HLLW storage tank. The measurement agrees with previous calculations of exposure rate, and provides confirmation for safe and effective radiation work plans and material selection for investigations and remediation of the storage tank facility. The measured radiation exposure rate profile is also used to confirm that the position of tank internal structures have not changed because of aging and corrosion, and to obtain, within a few mm, the level of liquid inside the tank. (author)

Automatic cryogenic liquid level controller is safe for use near combustible substances

Science.gov (United States)

Krejsa, M.

1966-01-01

Automatic mechanical liquid level controller that is independent of any external power sources is used with safety in the presence of combustibles. A gas filled capillary tube which leads from a pressurized chamber, is inserted into the cryogenic liquid reservoir and becomes a liquid level sensing element or probe.

Comparative estimates of risks arising from storage of intermediate level radioactive wastes

International Nuclear Information System (INIS)

Moore, D.

1986-04-01

Estimates are presented of risks arising from accidents occuring during storage of nine types of conditioned intermediate level waste. Additional data are introduced relating to the risks from accidents affecting raw waste, and to risks associated with the occupational doses received during normal operation of a waste store. Risks in all three categories are shown to be extremely small. (author)

Reinforced concrete in the intermediable-level nuclear waste repository

International Nuclear Information System (INIS)

Duffo, Gustavo

2009-01-01

The National Atomic Energy Commission (CNEA) is responsible for developing the nuclear waste disposal management programme. This programme contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive wastes. The proposed model is a near-surface monolithic repository similar to those in operation in El Cabril, Spain. The design of this type of repository is based on the use of multiple, independent and redundant barriers and the model foresees a period of 300 years of institutional post-closure control. Since the vault and cover are major components of the engineered barriers, the durability of these concrete structures is an important aspect for the facility integrity. This work presents laboratory investigations performed on the corrosion susceptibility of steel rebars embedded in two different types of high performance reinforced concretes, recently developed by the National Institute of Industrial Technology (Argentine). Concretes were made with cement with Blast Furnace Slag (CAH) and Silica Fume cement (CAH + SF). The aim of this work is to predict the service life of the intermediate level radioactive waste disposal vaults from data obtained from electrochemical techniques. Besides, the diffusion coefficients of aggressive species, such as chloride and carbon dioxide, were also determined. On the other hand, data obtained with corrosion sensors embedded in a vault prototype is also included. These sensors allow on-line measurements of several parameters related to the corrosion process such as rebar corrosion potential and corrosion current density; incoming oxygen flow that reaches the metal surface; concrete electrical resistivity; chloride concentration and internal concrete temperature. All the information obtained from both, laboratory tests and sensors will be used for the final design of the container in order to achieve a service life more or equal than the foreseen durability for this type of

The separation of solid and liquid components of mixtures

International Nuclear Information System (INIS)

Hunter, W.M.

1980-01-01

An improved method of separating solid and liquid components of mixtures is described which is particularly suited for use in automated radioimmunoassay systems in the analysis of bound and free fractions. A second liquid, having a density intermediate between those of the solid and liquid components, is delivered to the solid/ liquid mixture to form a discrete layer below the mixture and the solid separates into this lower liquid layer assisted by centrifugal force. The second liquid of intermediate density is an aqueous solution of a highly hydrophilic and electrically non-polar solute, such as an aqueous sucrose solution. Further liquids of intermediate density and progressively higher density may be delivered to form further discrete layers below the initial layer of the second dense liquid. After separation of the solid and liquid components of the mixture, the supernatant liquid component of the original mixture is removed in a controlled and non-turbulent manner. The method is illustrated in radioimmunoassays for platelet β-thromboglobulin and human follicle stimulating hormone. (U.K.)

Study on the development of an efficient and economical small scale management scheme for low and intermediate level radioactive wastes and its impact on the environment. Part of a coordinated programme

International Nuclear Information System (INIS)

Bartolome, Z.

1976-05-01

Efforts were made towards the establishment of a pilot-scale management system for the low and intermediate-level radioactive wastes of the Atomic Research Center. Practices in handling radioactive wastes are discussed and the assessment of their capabilities to meet the projections on the waste production is presented. The future waste management requirements of the Center was evaluated and comparative studies on the Lime-Soda and Phosphate Processes were conducted on simulated and raw liquid wastes with initial activity ranging from 10 -4 uCi/ml to 10 -2 uCi/ml, to establish the ideal parameters for best attaining maximum removal of radioactivity in liquids. The effectiveness of treatment was evaluated in terms of the decontamination factor, DF, obtained

Strategy for the disposal of low- and intermediate-level radwastes in Canada

International Nuclear Information System (INIS)

Dixon, D.F.

The intent of the strategy described is to optimize both safety and cost of disposal by classifying waste segments according to hazardous lifetime and to match these to two or more selected disposl concepts graded according to containment and isolation capabilities. The bulk of low- and intermediate-level radwastes arising in Canada are a relatively short-lived hazard requiring isolation for no more than a few hundred years. Burial of this segment at tens-of-metres in quatenary deposits has been proposed as a concept worth evaluating. It is expected that part of the low- and intermediate-level radwastes will be potentially hazardous for geological time periods. Once methods of isolation for long-lived fuel wastes have been identified, these could be utilized for wastes requiring isolation for longer than a few hundred years. Disposal of a hard-rock vault is being evaluated as a reference concept and costs are presented. It is proposed that waste classification may consider more than two categories to further reduce costs and to better accommodate the radiological character of wastes. The overall disposal strategy should be flexible enough to account for present waste management practices and anticipated future needs

Structural, dynamic, electronic, and vibrational properties of flexible, intermediate, and stressed rigid As-Se glasses and liquids from first principles molecular dynamics

Energy Technology Data Exchange (ETDEWEB)

Bauchy, M. [Department of Civil and Environmental Engineering, University of California, Los Angeles, California 90095-1593 (United States); Kachmar, A. [Laboratoire de Physique Théorique de la Matière Condensée, Université Pierre et Marie Curie, 4 Place Jussieu, F-75252 Paris Cedex 05 (France); Qatar Environment and Energy Research Institute, Qatar Foundation, P.O. Box 5825, Doha (Qatar); Micoulaut, M., E-mail: mmi@lptl.jussieu.fr [Laboratoire de Physique Théorique de la Matière Condensée, Université Pierre et Marie Curie, 4 Place Jussieu, F-75252 Paris Cedex 05 (France)

2014-11-21

The structural, vibrational, electronic, and dynamic properties of amorphous and liquid As{sub x}Se{sub 1-x} (0.10 intermediate phase in these glassy networks, observed at 0.27 liquid phase, thereby linking structural and dynamical atomic-scale fingerprints for the onset of rigidity within the network, while also providing a much more complex picture than the one derived from mean-field approaches of stiffness transitions.

Isoporphyrin Intermediate in Heme Oxygenase Catalysis

Science.gov (United States)

Evans, John P.; Niemevz, Fernando; Buldain, Graciela; de Montellano, Paul Ortiz

2008-01-01

Human heme oxygenase-1 (hHO-1) catalyzes the O2- and NADPH-dependent oxidation of heme to biliverdin, CO, and free iron. The first step involves regiospecific insertion of an oxygen atom at the α-meso carbon by a ferric hydroperoxide and is predicted to proceed via an isoporphyrin π-cation intermediate. Here we report spectroscopic detection of a transient intermediate during oxidation by hHO-1 of α-meso-phenylheme-IX, α-meso-(p-methylphenyl)-mesoheme-III, and α-meso-(p-trifluoromethylphenyl)-mesoheme-III. In agreement with previous experiments (Wang, J., Niemevz, F., Lad, L., Huang, L., Alvarez, D. E., Buldain, G., Poulos, T. L., and Ortiz de Montellano, P. R. (2004) J. Biol. Chem. 279, 42593–42604), only the α-biliverdin isomer is produced with concomitant formation of the corresponding benzoic acid. The transient intermediate observed in the NADPH-P450 reductase-catalyzed reaction accumulated when the reaction was supported by H2O2 and exhibited the absorption maxima at 435 and 930 nm characteristic of an isoporphyrin. Product analysis by reversed phase high performance liquid chromatography and liquid chromatography electrospray ionization mass spectrometry of the product generated with H2O2 identified it as an isoporphyrin that, on quenching, decayed to benzoylbiliverdin. In the presence of H218O2, one labeled oxygen atom was incorporated into these products. The hHO-1-isoporphyrin complexes were found to have half-lives of 1.7 and 2.4 h for the p-trifluoromethyl- and p-methyl-substituted phenylhemes, respectively. The addition of NADPH-P450 reductase to the H2O2-generated hHO-1-isoporphyrin complex produced α-biliverdin, confirming its role as a reaction intermediate. Identification of an isoporphyrin intermediate in the catalytic sequence of hHO-1, the first such intermediate observed in hemoprotein catalysis, completes our understanding of the critical first step of heme oxidation. PMID:18487208

Cryogenic Liquid Level-Sensing using Fiber-Optic Strain Sensor (FOSS) Technology Project

Data.gov (United States)

National Aeronautics and Space Administration — Armstrong innovators have developed a highly accurate method for measuring liquid levels using optical fibers. Unlike liquid level gauges that rely on discrete...

Good Old-Fashioned Artificial Consciousness and the Intermediate Level Fallacy

Directory of Open Access Journals (Sweden)

Riccardo Manzotti

2018-04-01

Full Text Available Recently, there has been considerable interest and effort to the possibility to design and implement conscious robots, i.e., the chance that robots may have subjective experiences. Typical approaches as the global workspace, information integration, enaction, cognitive mechanisms, embodiment, i.e., the Good Old-Fashioned Artificial Consciousness, henceforth, GOFAC, share the same conceptual framework. In this paper, we discuss GOFAC's basic tenets and their implication for AI and Robotics. In particular, we point out the intermediate level fallacy as the central issue affecting GOFAC. Finally, we outline a possible alternative conceptual framework toward robot consciousness.

Design of a store for encapsulated intermediate level radioactive waste

International Nuclear Information System (INIS)

Lloyd, A.I.; Robinson, G.; Price, M.S.T.

1989-01-01

The design of a new store for cemented intermediate level radioactive waste produced in unshielded 500 litre drums from the Winfrith Radwaste Treatment Plant is described. The store design has had to take account of local site constraints and disposal uncertainties. As a result, an innovative above ground storage tube design using interlocking, commercially available, concrete pipe rings has been selected. Other special features are that the store is easily capable of being extended whilst in service and is simple and cheap to decommission. A quality assessment facility for the drummed waste is an integral part of the store complex. (author)

Conditions for the test emplacement of intermediate-level radioactive wastes in chamber 8a of the 511 m level of the Asse Salt Mine

International Nuclear Information System (INIS)

1984-01-01

The Gesellschaft fuer Strahlen- und Umweltforschung mbH (GSF) emplaces intermediate-level radioactive wastes which accumulate in an activity involving the use of radioactive materials that is licensed or reported in the Federal Republic of Germany or which are stored on an interim basis by the appropriate licensing or inspection agencies in chamber 8a of the 511 m level of the Asse Salt Mine in Remlingen near Wolfenbuettel in conjunction with an engineering test program. The type and form of the intermediate-level wastes must conform to certain conditions so that there are no hazards to personnel and the repository during transfer and subsequent storage. It is therefore necessary for the radioactive wastes to be treated and packaged before delivery in such a way that they satisfy the conditions presented in this document. The GSF shall inform the companies and organizations delivering wastes about its experiences with emplacement operations. The Conditions for the Test Emplacement of Intermediate-Level Radioactive Wastes in Chamber 8a of the 511 m Level of the Asse Salt Mine must be adapted to conform to the latest state of science and the art. The GSF must therefore reserve the right to modify the conditions, allowing for an appropriate transition period

Neuroscience Intermediate-Level Care Units Staffed by Intensivists: Clinical Outcomes and Cost Analysis.

Science.gov (United States)

Kyeremanteng, Kwadwo; Hendin, Ariel; Bhardwaj, Kalpana; Thavorn, Kednapa; Neilipovitz, Dave; Kubelik, Dalibour; D'Egidio, Gianni; Stotts, Grant; Rosenberg, Erin

2017-01-01

With an aging population and increasing numbers of intensive care unit admissions, novel ways of providing quality care at reduced cost are required. Closed neurointensive care units improve outcomes for patients with critical neurological conditions, including decreased mortality and length of stay (LOS). Small studies have demonstrated the safety of intermediate-level units for selected patient populations. However, few studies analyze both cost and safety outcomes of these units. This retrospective study assessed clinical and cost-related outcomes in an intermediate-level neurosciences acute care unit (NACU) before and after the addition of an intensivist to the unit's care team. Starting in October 2011, an intensivist-led model was adopted in a 16-bed NACU unit, including daytime coverage by a dedicated intensivist. Data were obtained from all patients admitted 1 year prior to and 2 years after this intervention. Primary outcomes were LOS and hospital costs. Safety outcomes included mortality and readmissions. Descriptive and analytic statistics were calculated. Individual and total patient costs were calculated based on per-day NACU and ward cost estimates and significance measured using bootstrapping. A total of 2931 patients were included over the study period. Patients were on average 59.5 years and 53% male. The most common reasons for admission were central nervous system (CNS) tumor (27.6%), ischemic stroke (27%), and subarachnoid hemorrhage (11%). Following the introduction of an intensivist, there was a significant reduction in NACU and hospital LOS, by 1 day and 3 days, respectively. There were no differences in readmissions or mortality. Adding an intensivist produced an individual cost savings of US$963 in NACU and US$2687 per patient total hospital stay. An intensivist-led model of intermediate-level neurointensive care staffed by intensivists is safe, decreases LOS, and produces cost savings in a system increasingly strained to provide quality

Management for low and intermediate level wastes in Brazil

International Nuclear Information System (INIS)

Franzen, H.R.

1986-01-01

A research and demonstration project was developed, to offer management options for low and intermediate level radioactive wastes. The project considered: the experience of other countries; the laws and regulations according to internationally accepted standards; criteria and recommendations; the technical, socio-political realities, and the expectation of our countrie related to the nuclear power plants. Preliminary guidelines for waste acceptance critetia were established. The solution for shallow land burial was a multibarrier system. Since, there is no final decision about the repository localization it was decided that the waste produced by nuclear power plants will be kept on-site and those from medicine, agriculture, industry and research are sent to the IPEN/CNEN-SP for treatment and temporary storage. (Author/M.C.K.) [pt

Applications of low level liquid scintillation counting

International Nuclear Information System (INIS)

Noakes, J.E.

1983-01-01

Low level liquid scintillation counting is reviewed in terms of its present use and capabilities for measuring low activity samples. New areas of application of the method are discussed with special interest directed to the food industry and environmental monitoring. Advantages offered in the use of a low background liquid scintillation counter for the nuclear power industry and nuclear navy are discussed. Attention is drawn to the need for commercial development of such instrumentation to enable wider use of the method. A user clientele is suggested as is the required technology to create such a counter

Low- and intermediate-level waste management practices in Japan

International Nuclear Information System (INIS)

Tsuchiya, M.

1982-01-01

At present, disposal of low-level radioactive wastes is yet to be carried out in Japan. Liquid wastes, except for the diluted discharge of very low-level waste into the environment, are mostly solidified with cement or bitumen to be packed in 200 litre drums and put in storage. Solid wastes, on the other hand, are mostly put into in 200 litre drums, some of them being incinerated beforehand. Efforts are being made to develop technology for reducing the production of wastes. Regarding sea disposal, a test dumping program has been forestalled by the opposition of South Pacific islanders, but we are endeavoring to promote their understandings on this matter. Regarding land disposal, first we are going to start centralized storage, then shift to underground disposal

Glass-solidification method for high level radioactive liquid waste

International Nuclear Information System (INIS)

Kawamura, Kazuhiro; Kometani, Masayuki; Sasage, Ken-ichi.

1996-01-01

High level liquid wastes are removed with precipitates mainly comprising Mo and Zr, thereafter, the high level liquid wastes are mixed with a glass raw material comprising a composition having a B 2 O 3 /SiO 2 ratio of not less than 0.41, a ZnO/Li 2 O ratio of not less than 1.00, and an Al 2 O 3 /Li 2 O ratio of not less than 2.58, and they are melted and solidified into glass-solidification products. The liquid waste content in the glass-solidification products can be increased up to about 45% by using the glass raw material having such a predetermined composition. In addition, deposition of a yellow phase does not occur, and a leaching rate identical with that in a conventional case can be maintained. (T.M.)

A strategy for the improvement of the intermediate and low level radioactive waste management

International Nuclear Information System (INIS)

Benitez, J.C.; Salgado, M.; Jova, L.

1996-01-01

The work describes the surrent situation with regard to the management of intermediate and low level radioactive wastes that are generated in the country. Updated information is reffered on the quantities of stored wastes that are to be treated and conditioned at the facilities of the CPHR

An updated overview of low and intermediate level waste disposal facilities around the world

International Nuclear Information System (INIS)

Cuccia, Valeria; Uemura, George; Ferreira, Vinicius Verna M.; Tello, Cledola Cassia O. de; Malta, Ricardo Scott V.

2011-01-01

Low and intermediate level radioactive waste should be disposed off in proper disposal facilities. Some countries already have these facilities and others are planning theirs. Information about disposal facilities around the world is useful and necessary; however, data on this matter are usually scattered in official reports per country. In order to allow an easier access to this information, this paper aims to provide an overview of disposal facilities for low and intermediate level radioactive waste around the world, as updated as possible. Also, characteristics of the facilities are provided, when possible. Considering that the main source of radioactive waste are the activities of nuclear reactors in research or power generation, the paper will also provide a summarized overview of these reactors around the world, updated until April, 2011. This data collection may be an important tool for researchers, and other professionals in this field. Also, it might provide an overview about the final disposal of radioactive waste. (author)

Bituminization of low- and intermediate-level radioactive concentrates

International Nuclear Information System (INIS)

Breza, M.; Krejci, F.; Timulak, J.; Tibensky, L.

1985-01-01

The results and experiences are summed up from the research and development of the technology of bituminization of low- and intermediate-level radioactive concentrates generated in the operation of nuclear power plants with WWER-440 reactors. The experiments took place on a pilot plant bituminization line with various model solutions at an evaporator capacity of 70, 100 and 140 litres per hour. The composition of the solutions changed in dependence on the knowledge of the composition of actual concentrates in the V-1 nuclear power plant at Jaslovske Bohunice. The following factors were studied in the concentrate: the effect of its pH, its borate content and content of metal carbonates, the content of organic acid salts, the content of detergents, etc., on the process of bituminization. Physico-chemical conditions are described under which the operation of the evaporator was fail-safe and filling of the bituminization product with salts homogeneous. A low water content of up to 1% was achieved. The properties of the bituminization product were negatively affected by a high level of heavy metal oxides, surfactants, oxalates and citrates. In order to improve the properties of the product it will be necessary to replace bitumen emulsion Silembit-60 used as reinforcement matrix, by a different type of bitumen. (Z.M.)

Governance-Default Risk Relationship and the Demand for Intermediated and Non-Intermediated Debt

Directory of Open Access Journals (Sweden)

Husam Aldamen

2012-09-01

Full Text Available This paper explores the impact of corporate governance on the demand for intermediated debt (asset finance, bank debt, non-bank private debt and non-intermediated debt (public debt in the Australian debt market. Relative to other countries the Australian debt market is characterised by higher proportions of intermediated or private debt with a lower inherent level of information asymmetry in that private lenders have greater access to financial information (Gray, Koh & Tong 2009. Our firm level, cross-sectional evidence suggests that higher corporate governance impacts demand for debt via the mitigation of default risk. However, this relationship is not uniform across all debt types. Intermediated debt such as bank and asset finance debt are more responsive to changes in governance-default risk relationship than non-bank and non-intermediated debt. The implication is that a firm’s demand for different debt types will reflect its governance-default risk profile.

Conditioning of low- and intermediate-level radioactive wastes

International Nuclear Information System (INIS)

1983-01-01

The nuclear fuel cycle, together with the use of separated radioisotopes, in many endeavours generates a variety of low- and intermediate-level radioactive wastes. These waste materials contain quantities of radionuclides sufficient to present potential health risks to people if the wastes are not adequately managed, but usually insufficient quantities to require heat removal. Adequate management involves a series of steps which lead from the arising of the wastes to their safe disposal, steps which may include collection, segregation, treatment, volume reduction, conditioning, transport, interim storage and disposal. Each step is defined by the need to accommodate to the preceding one and to facilitate the ones that follow. This technical report describes primarily the technologies available for the conditioning steps (i.e., immobilization and packaging) and relates them to the other steps. In broad terms, the purpose of conditioning is to convert the wastes into packages that are suitable for transport, storage and disposal

Environmental effects of disposal of intermediate-level wastes by shale fracturing

International Nuclear Information System (INIS)

Weeren, H.O.

1978-01-01

Shale fracturing is a process currently being used at the Oak Ridge National Laboratory for the permanent disposal of locally generated, intermediate-level waste solutions. In this process, the waste is mixed with a solids blend of cement and other additives; the resulting grout is then injected into an impermeable shale formation at a depth of 700 to 1000 ft. A few hours after completion of the injection, the grout sets and the radioactive waste are fixed in the shale formation. An analysis of environmental effects of normal operation and possible accident situations is discussed

Assessment of Student Achievement: Evaluation of Student Achievement at the Intermediate Level. Final Report.

Science.gov (United States)

Wahlstrom, M.; And Others

Evaluation and assessment procedures of Ontario, Canada principals and teachers at the Intermediate level (grades 7 and 8) were examined. Extensive questionnaires were returned by 134 principals and 225 teachers divided across the subject areas of English, Mathematics, Science, Languages, History, Home Economics or Shop, Arts, and Physical…

Development of agency guidance for nuclear industry submissions for conditioning intermediate level waste

International Nuclear Information System (INIS)

2001-01-01

The project was carried out by RM Consultants with the overall intention of providing the Environment Agency with a sound basis on which to develop guidance on the conditioning of intermediate level waste (ILW). Waste producers are currently in the process of retrieving and conditioning many of its ILW waste streams. This is at a time where the nature and timing of any future disposal route for these wastes is uncertain. The Agency is concerned that decisions taken on how ILW should be conditioned take into account matters of interest to the Agency, such as the future disposability of wastes, the production of secondary wastes and releases to the environment. This study provides information on the arrangements by which waste producers' proposals for the conditioning of intermediate level waste are assessed, and on the Agency's role in liaising with the Nuclear Installations Inspectorate, waste producers and Nirex. The report makes recommendations on the content and handling of waste producers' proposals in order that the Agency can satisfy itself that the environmental impact of waste conditioning and the disposability of the resultant waste packages is addressed in a timely and consistent manner

Level crossing analysis of chemically induced dynamic nuclear polarization: Towards a common description of liquid-state and solid-state cases

Energy Technology Data Exchange (ETDEWEB)

Sosnovsky, Denis V.; Ivanov, Konstantin L., E-mail: ivanov@tomo.nsc.ru [International Tomography Centre of SB RAS, Institutskaya 3a, 630090, Novosibirsk (Russian Federation); Novosibirsk State University, Pirogova 2, 630090, Novosibirsk (Russian Federation); Jeschke, Gunnar [Institut für Physikalische Chemie, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich (Switzerland); Matysik, Jörg [Institut für Analytische Chemie, Universität Leipzig, Linnéstr. 3, D-04103 Leipzig (Germany); Vieth, Hans-Martin [International Tomography Centre of SB RAS, Institutskaya 3a, 630090, Novosibirsk (Russian Federation); Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin (Germany)

2016-04-14

Chemically Induced Dynamic Nuclear Polarization (CIDNP) is an efficient method of creating non-equilibrium polarization of nuclear spins by using chemical reactions, which have radical pairs as intermediates. The CIDNP effect originates from (i) electron spin-selective recombination of radical pairs and (ii) the dependence of the inter-system crossing rate in radical pairs on the state of magnetic nuclei. The CIDNP effect can be investigated by using Nuclear Magnetic Resonance (NMR) methods. The gain from CIDNP is then two-fold: it allows one to obtain considerable amplification of NMR signals; in addition, it provides a very useful tool for investigating elusive radicals and radical pairs. While the mechanisms of the CIDNP effect in liquids are well established and understood, detailed analysis of solid-state CIDNP mechanisms still remains challenging; likewise a common theoretical frame for the description of CIDNP in both solids and liquids is missing. Difficulties in understanding the spin dynamics that lead to the CIDNP effect in the solid-state case are caused by the anisotropy of spin interactions, which increase the complexity of spin evolution. In this work, we propose to analyze CIDNP in terms of level crossing phenomena, namely, to attribute features in the CIDNP magnetic field dependence to Level Crossings (LCs) and Level Anti-Crossings (LACs) in a radical pair. This approach allows one to describe liquid-state CIDNP; the same holds for the solid-state case where anisotropic interactions play a significant role in CIDNP formation. In solids, features arise predominantly from LACs, since in most cases anisotropic couplings result in perturbations, which turn LCs into LACs. We have interpreted the CIDNP mechanisms in terms of the LC/LAC concept. This consideration allows one to find analytical expressions for a wide magnetic field range, where several different mechanisms are operative; furthermore, the LAC description gives a way to determine CIDNP sign

Probing the Natural World, Level III, Student Guide: Investigating Variation. Intermediate Science Curriculum Study.

Science.gov (United States)

Bonar, John R., Ed.; Hathway, James A., Ed.

This is the student's text of one unit of the Intermediate Science Curriculum Study (ISCS) for level III students (grade 9). This unit focuses on diversity in human populations, measurement, and data collection. Numerous activities are given and optional excursions encourage students to pursue a topic in greater depth. Data tables within the…

Problems related to final disposal of high-level radioactive waste in Russia

International Nuclear Information System (INIS)

Velichkin, Vasily I.

1999-01-01

According to this presentation, the radioactivity of the total amount of radioactive waste accumulated in Russia to date is 1.5*10 9 Ci and of spent fuel 4.5*10 9 Ci. A table is given that shows the source, type, volume activity and storage type under the responsibility of the different departments and enterprises. 99.9% of the wastes are accumulated at the enterprises of Minatom of the Russian Federation. Some companies inject their liquid wastes from ionisation sources and intermediate liquid waste from the nuclear power industry into deep-seated reliably isolated aquifers. The Mayak plant has released liquid low-level and intermediate wastes into artificial reservoirs and Lake Karachay. Liquid high-level wastes are always stored in special tanks at interim storage facilities. A large number of nuclear submarines are laid up in North-Western Russia and East Russia, with spent fuel still in place as the interim storages in these regions are filled up and there are no conditioning plants. Underground disposal is considered the best way of isolating radioactive waste for as long as it is hazardous to the environment. Two new technologies are discussed. One involves including long-lived isotopes in high-stable mineral matrices, the other uses selective separation from the bulk of wastes. The matrices should be disposed of deep in the Earth's crust, at least 2-3 km down. Liquid waste of caesium-strontium fraction must be transformed into glass-like form and stored underground at a depth of a few hundred metres. Short-lived low level and intermediate level wastes should be conditioned and then deposited in subsurface ferroconcrete repositories constructed in clays. Finally, the presentation discusses the selection of sites and conditions for radioactive waste disposal. Two sites are discussed, the Mayak plant and a possible site at Mining Chemical Combine in Krasnoyarsk-26

Divide and conquer: intermediate levels of population fragmentation maximize cultural accumulation.

Science.gov (United States)

Derex, Maxime; Perreault, Charles; Boyd, Robert

2018-04-05

Identifying the determinants of cumulative cultural evolution is a key issue in the interdisciplinary field of cultural evolution. A widely held view is that large and well-connected social networks facilitate cumulative cultural evolution because they promote the spread of useful cultural traits and prevent the loss of cultural knowledge through factors such as drift. This view stems from models that focus on the transmission of cultural information, without considering how new cultural traits actually arise. In this paper, we review the literature from various fields that suggest that, under some circumstances, increased connectedness can decrease cultural diversity and reduce innovation rates. Incorporating this idea into an agent-based model, we explore the effect of population fragmentation on cumulative culture and show that, for a given population size, there exists an intermediate level of population fragmentation that maximizes the rate of cumulative cultural evolution. This result is explained by the fact that fully connected, non-fragmented populations are able to maintain complex cultural traits but produce insufficient variation and so lack the cultural diversity required to produce highly complex cultural traits. Conversely, highly fragmented populations produce a variety of cultural traits but cannot maintain complex ones. In populations with intermediate levels of fragmentation, cultural loss and cultural diversity are balanced in a way that maximizes cultural complexity. Our results suggest that population structure needs to be taken into account when investigating the relationship between demography and cumulative culture.This article is part of the theme issue 'Bridging cultural gaps: interdisciplinary studies in human cultural evolution'. © 2018 The Author(s).

Study on Calculation of Liquid Level And Storage of Tanks for LNG-fueled Vessels

Science.gov (United States)

Li, Kun; Wang, Guoqing; Liu, Chang

2018-01-01

As the ongoing development of the application of LNG as a clean energy in waterborne transport industry, the fleet scale of LNG-fueled vessels enlarged and the safety operation has attracted more attention in the industry. Especially the accurate detection of liquid level of LNG tanks is regarded as an important issue to ensure a safe and stable operation of LNG-fueled ships and a key parameter to keep the proper functioning of marine fuel storage system, supply system and safety control system. At present, detection of LNG tank liquid level mainly adopts differential pressure detection method. Liquid level condition could be found from the liquid level reference tables. However in practice, since LNG-fueled vessels are generally not in a stationary state, liquid state within the LNG tanks will constantly change, the detection of storage of tanks only by reference to the tables will cause deviation to some extent. By analyzing the temperature under different pressure, the effects of temperature change on density and volume integration calculation, a method of calculating the liquid level and storage of LNG tanks is put forward making the calculation of liquid level and actual storage of LNG tanks more accurately and providing a more reliable basis for the calculation of energy consumption level and operation economy for LNG-fueled vessels.

Comprehensive development plans for the low- and intermediate-level radioactive waste disposal facility in Korea and preliminary safety assessment

Energy Technology Data Exchange (ETDEWEB)

Jung, Kang Il; Kim, Jin Hyeong; Kwon, Mi Jin; Jeong, Mi Seon; Hong, Sung Wook; Park, Jin Beak [Korea Radioactive Waste Agency, Daejeon (Korea, Republic of)

2016-12-15

The disposal facility in Gyeongju is planning to dispose of 800,000 packages of low- and intermediate- level radioactive waste. This facility will be developed as a complex disposal facility that has various types of disposal facilities and accompanying management. In this study, based on the comprehensive development plan of the disposal facility, a preliminary post-closure safety assessment is performed to predict the phase development of the total capacity for the 800,000 packages to be disposed of at the site. The results for each scenario meet the performance target of the disposal facility. The assessment revealed that there is a significant impact of the inventory of intermediate-level radionuclide waste on the safety evaluation. Due to this finding, we introduce a disposal limit value for intermediate-level radioactive waste. With stepwise development of safety case, this development plan will increase the safety of disposal facilities by reducing uncertainties within the future development of the underground silo disposal facilities.

Project Guarantee 1985. Repository for low- and intermediate-level radioactive waste: construction and operation

International Nuclear Information System (INIS)

Anon.

1985-01-01

A constructional engineering project study aimed at clarification of the feasibility of a repository for low- and intermediate-level radioactive waste (type B repository) has been carried out; the study is based on a model data-set derived from the geological, rock mechanical and topographical characterictics of one of Nagra's planned exploration areas. Final storage is effected in subterranean rock caverns accessed by horizontal tunnel. The reception area also is sited below the surface. Storage is conceived in such a way that, after closure of the repository, maintenance and supervision can be dispensed with and a guarantee of high long-term safety can nevertheless be provided. The envisaged repository consists of an entry tunnel for road vehicles and a reception area with a series of caverns for receiving waste, for additional technical facilities and for the production of the concrete back-fill material. The connecting tunnel is serviced by a tunnel railway and the actual repository area consists of several storage caverns. The repository is intended to accomodate a total of 200'000 m3 of solidified low- and intermediate-level waste. Valanginian marl is assumed as the host rock, although it would also be basically possible to house the proposed installations in other host rocks. The excavated material will total around 1'000'000 m3. The construction time for the whole installation is estimated as about 7 years and a working team of around 30 people will be required for the estimated 60-year operational duration. The project described in the present report justifies the conclusion that construction of a repository for low-and intermediate-level radioactive waste is feasible with present-day technology. This conclusion takes into consideration quantitative and operational constraints as well as geological and hydrogeological data relevant to constructional engineering. The latter are derived from a model data-set based on a specific locality

V-T theory for the self-intermediate scattering function in a monatomic liquid.

Science.gov (United States)

Wallace, Duane C; Chisolm, Eric D; De Lorenzi-Venneri, Giulia

2017-02-08

In V-T theory the atomic motion is harmonic vibrations in a liquid-specific potential energy valley, plus transits, which move the system rapidly among the multitude of such valleys. In its first application to the self intermediate scattering function (SISF), V-T theory produced an accurate account of molecular dynamics (MD) data at all wave numbers q and time t. Recently, analysis of the mean square displacement (MSD) resolved a crossover behavior that was not observed in the SISF study. Our purpose here is to apply the more accurate MSD calibration to the SISF, and assess the results. We derive and discuss the theoretical equations for vibrational and transit contributions to the SISF. The time evolution is divided into three successive intervals: the vibrational interval when the vibrational contribution alone accurately accounts for the MD data; the crossover when the vibrational contribution saturates and the transit contribution becomes resolved; and the diffusive interval when the transit contribution alone accurately accounts for the MD data. The resulting theoretical error is extremely small at all q and t. V-T theory is compared to mode-coupling theories for the MSD and SISF, and to recent developments in Brownian motion experiments and theory.

V-T theory for the self-intermediate scattering function in a monatomic liquid

International Nuclear Information System (INIS)

Wallace, Duane C; Chisolm, Eric D; De Lorenzi-Venneri, Giulia

2017-01-01

In V-T theory the atomic motion is harmonic vibrations in a liquid-specific potential energy valley, plus transits, which move the system rapidly among the multitude of such valleys. In its first application to the self intermediate scattering function (SISF), V-T theory produced an accurate account of molecular dynamics (MD) data at all wave numbers q and time t . Recently, analysis of the mean square displacement (MSD) resolved a crossover behavior that was not observed in the SISF study. Our purpose here is to apply the more accurate MSD calibration to the SISF, and assess the results. We derive and discuss the theoretical equations for vibrational and transit contributions to the SISF. The time evolution is divided into three successive intervals: the vibrational interval when the vibrational contribution alone accurately accounts for the MD data; the crossover when the vibrational contribution saturates and the transit contribution becomes resolved; and the diffusive interval when the transit contribution alone accurately accounts for the MD data. The resulting theoretical error is extremely small at all q and t . V-T theory is compared to mode-coupling theories for the MSD and SISF, and to recent developments in Brownian motion experiments and theory. (paper)

Probing the Natural World, Level III, Teacher's Edition: Investigating Variation. Intermediate Science Curriculum Study.

Science.gov (United States)

Bonar, John R., Ed.; Hathway, James A., Ed.

This is the teacher's edition of one of the eight units of the Intermediate Science Curriculum Study (ISCS) for level III students (grade 9). This unit focuses on diversity in human populations, measurement, and data collection. Optional excursions are described for students who wish to study a topic in greater depth. An introduction describes…

Probing the Natural World, Level III, Student Guide: What's Up? Intermediate Science Curriculum Study.

Science.gov (United States)

Bonar, John R., Ed.; Hathway, James A., Ed.

This is the student's text of one unit of the Intermediate Science Curriculum Study (ISCS) for level III students (grade 9). The chapters contain basic information about rockets, space, and principles of physics, as well as activities related to the subject and optional excursions. A section of introductory notes to the student discusses how the…

Automated Liquid-Level Control of a Nutrient Reservoir for a Hydroponic System

Science.gov (United States)

Smith, Boris; Asumadu, Johnson A.; Dogan, Numan S.

1997-01-01

A microprocessor-based system for control of the liquid level of a nutrient reservoir for a plant hydroponic growing system has been developed. The system uses an ultrasonic transducer to sense the liquid level or height. A National Instruments' Multifunction Analog and Digital Input/Output PC Kit includes NI-DAQ DOS/Windows driver software for an IBM 486 personal computer. A Labview Full Development system for Windows is the graphical programming system being used. The system allows liquid level control to within 0.1 cm for all levels tried between 8 and 36 cm in the hydroponic system application. The detailed algorithms have been developed and a fully automated microprocessor based nutrient replenishment system has been described for this hydroponic system.

High-resolution two-dimensional liquid chromatography analysis of key linker drug intermediate used in antibody drug conjugates.

Science.gov (United States)

Venkatramani, C J; Huang, Shu Rong; Al-Sayah, Mohammad; Patel, Ila; Wigman, Larry

2017-10-27

In this manuscript, the application of high-resolution sampling (HRS) two-dimensional liquid chromatography (2D-LC) in the detailed analysis of key linker drug intermediate is presented. Using HRS, selected regions of the primary column eluent were transferred to a secondary column with fidelity enabling qualitative and quantitative analysis of linker drugs. The primary column purity of linker drug intermediate ranged from 88.9% to 94.5% and the secondary column purity ranged from 99.6% to 99.9%, showing lot-to-lot variability, significant differences between the three lots, and substantiating the synthetic and analytical challenges of ADCs. Over 15 impurities co-eluting with the linker drug intermediate in the primary dimension were resolved in the secondary dimension. The concentrations of most of these impurities were over three orders of magnitude lower than the linker drug. Effective peak focusing and high-speed secondary column analysis resulted in sharp peaks in the secondary dimension, improving the signal-to-noise ratios. The sensitivity of 2D-LC separation was over five fold better than conventional HPLC separation. The limit of quantitation (LOQ) was less than 0.01%. Many peaks originating from primary dimension were resolved into multiple components in the complementary secondary dimension, demonstrating the complexity of these samples. The 2D-LC was highly reproducible, showing good precision between runs with%RSD of peak areas less than 0.1 for the main component. The absolute difference in the peak areas of impurities less than 0.1% were within ±0.01% and for impurities in the range of 0.1%-0.3%, the absolute difference were ±0.02%, which are comparable to 1D-LC. The overall purity of the linker drug intermediate was determined from the product of primary and secondary column purity (HPLC Purity=%peak area of main component in the primary dimension×%peak area of main component in the secondary dimension). Additionally, the 2D-LC separation enables

Development of a test system for high level liquid waste partitioning

OpenAIRE

Duan Wu H.; Chen Jing; Wang Jian C.; Wang Shu W.; Wang Xing H.

2015-01-01

The partitioning and transmutation strategy has increasingly attracted interest for the safe treatment and disposal of high level liquid waste, in which the partitioning of high level liquid waste is one of the critical technical issues. An improved total partitioning process, including a tri-alkylphosphine oxide process for the removal of actinides, a crown ether strontium extraction process for the removal of strontium, and a calixcrown ether cesium extra...

Development of the liquid level meters for the PandaX dark matter detector

International Nuclear Information System (INIS)

Hu Jie; Gong Haowei; Lin Qing; Ni Kaixuan; Wei Yuehuan; Xiao Mengjiao; Xiao Xiang; Zhao Li; Tan Andi

2014-01-01

The two-phase xenon detector is at the frontier of dark matter direct search. This kind of detector uses liquid xenon as the sensitive target and is operated in two-phase (liquid/gas) mode, where the liquid level needs to be monitored and controlled in sub-millimeter precision. In this paper, we present a detailed design and study of two kinds of level meters for the PandaX dark matter detector. The long level meter is used to monitor the overall liquid level while short level meters are used to monitor the inclination of the detector. These level meters are cylindrical capacitors that are custom-made from two concentric metal tubes. Their capacitance values are read out by a universal transducer interface chip and are recorded by the PandaX slow control system. We present the developments that lead to level meters with long-term stability and sub-millimeter precision. Fluctuations (standard deviations) of less than 0.02 mm for the short level meters and less than 0.2 mm for the long level meter were achieved during a few days of test operation. (authors)

Long-Period Fiber Grating Sensors for the Measurement of Liquid Level and Fluid-Flow Velocity

Directory of Open Access Journals (Sweden)

Jian-Neng Wang

2012-04-01

Full Text Available This paper presents the development and assessment of two types of Long Period Fiber Grating (LPFG-based sensors including a mobile liquid level sensor and a reflective sensor for the measurement of liquid level and fluid-flow velocity. Shewhart control charts were used to assess the liquid level sensing capacity and reliability of the mobile CO2-laser engraved LPFG sensor. There were ten groups of different liquid level experiment and each group underwent ten repeated wavelength shift measurements. The results showed that all measurands were within the control limits; thus, this mobile sensor was reliable and exhibited at least 100-cm liquid level measurement capacity. In addition, a reflective sensor consisting of five LPFGs in series with a reflective end has been developed to evaluate the liquid level and fluid-flow velocity. These five LPFGs were fabricated by the electrical arc discharge method and the reflective end was coated with silver by Tollen’s test. After each liquid level experiment was performed five times, the average values of the resonance wavelength shifts for LPFG Nos. 1–5 were in the range of 1.35–9.14 nm. The experimental findings showed that the reflective sensor could be used to automatically monitor five fixed liquid levels. This reflective sensor also exhibited at least 100-cm liquid level measurement capacity. The mechanism of the fluid-flow velocity sensor was based on analyzing the relationship among the optical power, time, and the LPFG’s length. There were two types of fluid-flow velocity measurements: inflow and drainage processes. The differences between the LPFG-based fluid-flow velocities and the measured average fluid-flow velocities were found in the range of 8.7–12.6%. For the first time to our knowledge, we have demonstrated the feasibility of liquid level and fluid-flow velocity sensing with a reflective LPFG-based sensor without modifying LPFGs or coating chemical compounds.

Long-Period Fiber Grating Sensors for the Measurement of Liquid Level and Fluid-Flow Velocity

Science.gov (United States)

Wang, Jian-Neng; Luo, Ching-Ying

2012-01-01

This paper presents the development and assessment of two types of Long Period Fiber Grating (LPFG)-based sensors including a mobile liquid level sensor and a reflective sensor for the measurement of liquid level and fluid-flow velocity. Shewhart control charts were used to assess the liquid level sensing capacity and reliability of the mobile CO2-laser engraved LPFG sensor. There were ten groups of different liquid level experiment and each group underwent ten repeated wavelength shift measurements. The results showed that all measurands were within the control limits; thus, this mobile sensor was reliable and exhibited at least 100-cm liquid level measurement capacity. In addition, a reflective sensor consisting of five LPFGs in series with a reflective end has been developed to evaluate the liquid level and fluid-flow velocity. These five LPFGs were fabricated by the electrical arc discharge method and the reflective end was coated with silver by Tollen's test. After each liquid level experiment was performed five times, the average values of the resonance wavelength shifts for LPFG Nos. 1–5 were in the range of 1.35–9.14 nm. The experimental findings showed that the reflective sensor could be used to automatically monitor five fixed liquid levels. This reflective sensor also exhibited at least 100-cm liquid level measurement capacity. The mechanism of the fluid-flow velocity sensor was based on analyzing the relationship among the optical power, time, and the LPFG's length. There were two types of fluid-flow velocity measurements: inflow and drainage processes. The differences between the LPFG-based fluid-flow velocities and the measured average fluid-flow velocities were found in the range of 8.7–12.6%. For the first time to our knowledge, we have demonstrated the feasibility of liquid level and fluid-flow velocity sensing with a reflective LPFG-based sensor without modifying LPFGs or coating chemical compounds. PMID:22666046

Long-period fiber grating sensors for the measurement of liquid level and fluid-flow velocity.

Science.gov (United States)

Wang, Jian-Neng; Luo, Ching-Ying

2012-01-01

This paper presents the development and assessment of two types of Long Period Fiber Grating (LPFG)-based sensors including a mobile liquid level sensor and a reflective sensor for the measurement of liquid level and fluid-flow velocity. Shewhart control charts were used to assess the liquid level sensing capacity and reliability of the mobile CO(2)-laser engraved LPFG sensor. There were ten groups of different liquid level experiment and each group underwent ten repeated wavelength shift measurements. The results showed that all measurands were within the control limits; thus, this mobile sensor was reliable and exhibited at least 100-cm liquid level measurement capacity. In addition, a reflective sensor consisting of five LPFGs in series with a reflective end has been developed to evaluate the liquid level and fluid-flow velocity. These five LPFGs were fabricated by the electrical arc discharge method and the reflective end was coated with silver by Tollen's test. After each liquid level experiment was performed five times, the average values of the resonance wavelength shifts for LPFG Nos. 1-5 were in the range of 1.35-9.14 nm. The experimental findings showed that the reflective sensor could be used to automatically monitor five fixed liquid levels. This reflective sensor also exhibited at least 100-cm liquid level measurement capacity. The mechanism of the fluid-flow velocity sensor was based on analyzing the relationship among the optical power, time, and the LPFG's length. There were two types of fluid-flow velocity measurements: inflow and drainage processes. The differences between the LPFG-based fluid-flow velocities and the measured average fluid-flow velocities were found in the range of 8.7-12.6%. For the first time to our knowledge, we have demonstrated the feasibility of liquid level and fluid-flow velocity sensing with a reflective LPFG-based sensor without modifying LPFGs or coating chemical compounds.

Removal of radioruthenium from alkaline intermediate level radioactive waste solution : a laboratory investigation

International Nuclear Information System (INIS)

Samanta, S.K.; Theyyunni, T.K.

1994-01-01

Various methods were investigated in the laboratory for the removal of radioruthenium from alkaline intermediate level radioactive waste solutions of reprocessing plant origin. The methods included batch equilibration with different ion exchangers and sorbents, column testing and chemical precipitation. A column method using zinc-activated carbon mixture and a chemical precipitation method using ferrous salt along with sodium sulphite were found to be promising for plant scale application. (author). 10 refs., 3 figs., 7 tabs

Language in use intermediate : classroom book

CERN Document Server

Doff, Adrian

1995-01-01

ach of the four levels comprises about 80 hours of class work, with additional time for the self-study work. The Teacher's Book contains all the pages from the Classroom Book, with interleaved teaching notes including optional activities to cater for different abilities. There is a video to accompany the Beginner, Pre-intermediate and Intermediate levels. Each video contains eight stimulating and entertaining short programmes, as well as a booklet of photocopiable activities. Free test material is available in booklet and web format for Beginner and Pre-intermediate levels. Visit www.cambridge.org/elt/liu or contact your local Cambridge University Press representative.

Language in use intermediate : teacher's book

CERN Document Server

Doff, Adrian

1998-01-01

Each of the four levels comprises about 80 hours of class work, with additional time for the self-study work. The Teacher's Book contains all the pages from the Classroom Book, with interleaved teaching notes including optional activities to cater for different abilities. There is a video to accompany the Beginner, Pre-intermediate and Intermediate levels. Each video contains eight stimulating and entertaining short programmes, as well as a booklet of photocopiable activities. Free test material is available in booklet and web format for Beginner and Pre-intermediate levels. Visit www.cambridge.org/elt/liu or contact your local Cambridge University Press representative.

Low level radioactive liquid waste decontamination by electrochemical way

International Nuclear Information System (INIS)

Tronche, E.

1994-10-01

As part of the work on decontamination treatments for low level radioactive aqueous liquid wastes, the study of an electro-chemical process has been chosen by the C.E.A. at the Cadarache research centre. The first part of this report describes the main methods used for the decontamination of aqueous solutions. Then an electro-deposition process and an electro-dissolution process are compared on the basis of the decontamination results using genuine radioactive aqueous liquid waste. For ruthenium decontamination, the former process led to very high yields (99.9 percent eliminated). But the elimination of all the other radionuclides (antimony, strontium, cesium, alpha emitters) was only favoured by the latter process (90 percent eliminated). In order to decrease the total radioactivity level of the waste to be treated, we have optimized the electro-dissolution process. That is why the chemical composition of the dissolved anode has been investigated by a mixture experimental design. The radionuclides have been adsorbed on the precipitating products. The separation of the precipitates from the aqueous liquid enabled us to remove the major part of the initial activity. On the overall process some operations have been investigated to minimize waste embedding. Finally, a pilot device (laboratory scale) has been built and tested with genuine radioactive liquid waste. (author). 77 refs., 41 tabs., 55 figs., 4 appendixes

Conceptual designs for waste quality checking facilities for low level and intermediate level radioactive wastes and hazardous waste

International Nuclear Information System (INIS)

Driver, S.; Griffiths, M.; Leonard, C.D.; Smith, D.L.G.

1992-01-01

This report summarises work carried out on the design of facilities for the quality checking of Intermediate and Low Level Radioactive Waste and Hazardous Waste. The procedures used for the quality checking of these categories of waste are summarised. Three building options are considered: a separate LLW facility, a combined facility for LLW and HW and a Waste Quality Checking Facility for the three categories of waste. Budget Cost Estimates for the three facilities are given based on 1991 prices. (author)

Optical Mass Gauging System for Measuring Liquid Levels in a Reduced Gravity Environment

Science.gov (United States)

Sullenberger, Ryan M.; Munoz, Wesley M.; Lyon, Matt P.; Vogel, Kenny; Yalin, Azer P.; Korman, Valentin; Polzin, Kurt A.

2010-01-01

A compact and rugged fiber-coupled liquid volume sensor designed for flight on a sounding rocket platform is presented. The sensor consists of a Mach-Zehnder interferometer capable of measuring the amount of liquid contained in a tank under any gravitational conditions, including a microgravity environment, by detecting small changes in the index of refraction of the gas contained within a sensing region. By monitoring changes in the interference fringe pattern as the system undergoes a small compression provided by a piston, the ullage volume of a tank can be directly measured allowing for a determination of the liquid volume. To demonstrate the technique, data are acquired using two tanks containing different volumes of liquid, which are representative of the levels of liquid in a tank at different time periods during a mission. The two tanks are independently exposed to the measurement apparatus, allowing for a determination of the liquid level in each. In a controlled, laboratory test of the unit, the system demonstrated a capability of measuring a liquid level in an individual tank of 10.53 mL with a 2% error. The overall random uncertainty for the flight system is higher than that one test, at +/- 1.5 mL.

Region based route planning - Multi-abstraction route planning based on intermediate level vision processing

Science.gov (United States)

Doshi, Rajkumar S.; Lam, Raymond; White, James E.

1989-01-01

Intermediate and high level processing operations are performed on vision data for the organization of images into more meaningful, higher-level topological representations by means of a region-based route planner (RBRP). The RBRP operates in terrain scenarios where some or most of the terrain is occluded, proceeding without a priori maps on the basis of two-dimensional representations and gradient-and-roughness information. Route planning is accomplished by three successive abstractions and yields a detailed point-by-point path by searching only within the boundaries of relatively small regions.

STUTTERING THERAPY FOR A CHILD AT INTERMEDIATE STUTTERING LEVEL

Directory of Open Access Journals (Sweden)

Nevzeta SALIHOVIKJ

2009-11-01

Full Text Available Stuttering therapy very often demands combination of various approaches or its modification. The main purpose of this study was to present an integrated approach to stuttering modification therapy and fluency shaping therapy for an intermediate school-age male stutterer (11 years old.The therapy for the child lasted for 12 months, sessions have been carried out twice a week, each session lasted for 45 minutes. The child still attends the therapy. The therapy uses integration of stuttering modification therapy and fluency shaping therapy. For the purpose of the fluency shaping therapy, delayed auditory feedback program is applied. During the stuttering modification therapy the child has been taught how to stutter more easily which implies prolongation of all sounds in words on which child stutters, with easy and soft transition from one sound to another. It is continuously being worked with the child on reducing negative feelings and attitudes as well as elimination of avoidance of words and speaking situations. We explained to the parents the treatment program and their role in the program realization. We also explained the possible causes of stuttering, and tried to identify and reduce fluency distractors, and engage the child in as many situations as possible which improved speech fluency.After the application of this program the child has improved fluency during the conversation in clinical and nonclinical conditions (environment. This fluency consists of spontaneous and controlled fluency. Furthermore, fear of speaking and avoidance of speech situations are significantly reduced. On the basis of the applied therapy on the child at intermediate stuttering level it can be concluded that it is possible to integrate successfully both approaches: stuttering modification therapy and fluency shaping therapy.

Intermediate-level crossings of a first-passage path

International Nuclear Information System (INIS)

Bhat, Uttam; Redner, S

2015-01-01

We investigate some simple and surprising properties of a one-dimensional Brownian trajectory with diffusion coefficient D that starts at the origin and: (i) is at X at time T, or (ii) first reaches X at time T. We determine the most likely location of the first-passage trajectory from (0, 0) to (X, T) and its distribution at any intermediate time t < T. A first-passage path typically starts out by being repelled from its final location when X 2 /DT ≪ 1. We also determine the distribution of times when the trajectory first crosses and last crosses an arbitrary intermediate position x < X. The distribution of first-crossing times may be unimodal or bimodal, depending on whether X 2 /DT ≪ 1 or X 2 /DT ≫ 1. The form of the first-crossing probability in the bimodal regime is qualitatively similar to, but more singular than, the well-known arcsine law. (paper)

Licence applications for low and intermediate level waste predisposal facilities: A manual for operators

International Nuclear Information System (INIS)

2009-07-01

This publication covers all predisposal waste management facilities and practices for receipt, pretreatment (sorting, segregation, characterization), treatment, conditioning, internal relocation and storage of low and intermediate level radioactive waste, including disused sealed radioactive sources. The publication contains an Annex presenting the example of a safety assessment for a small radioactive waste storage facility. Facilities dealing with both short lived and long lived low and intermediate level waste generated from nuclear applications and from operation of small nuclear research reactors are included in the scope. Processing and storage facilities for high activity disused sealed sources and sealed sources containing long lived radionuclides are also covered. The publication does not cover facilities processing or storing radioactive waste from nuclear power plants or any other industrial scale nuclear fuel cycle facilities. Disposal facilities are excluded from the scope of this publication. Authorization process can be implemented in several stages, which may start at the site planning and the feasibility study stage and will continue through preliminary design, final design, commissioning, operation and decommissioning stages. This publication covers primarily the authorization needed to take the facility into operation

Design, Development and Testing of a Semi Cylindrical Capacitive Sensor for Liquid Level Measurement

Directory of Open Access Journals (Sweden)

Sagarika PAL

2010-05-01

Full Text Available In the present paper a low cost noncontact semi cylindrical capacitive type liquid level sensor has been designed, developed and tested. The semi cylindrical capacitive sensor consisting of two thin semi cylindrical metal plates separated by a gap distance and mounted around a non conducting storage tank, has been used to measure the liquid level in the tank. The measured capacitance variation with variation of liquid level is linear and obtained in the nano farad range which again has been converted into voltage variation by using proper signal conditioning circuit. Since the sensor is noncontact type it can be used for both conducting and non conducting type of liquid contained within a non conducting tank. For converting the capacitance variation in to voltage variation a series R-L-C resonating circuit has been used instead of conventional bridge circuit. Experimental results confirm the satisfactory performance of the sensor for liquid level measurement.

Liquid-state physical chemistry fundamentals, modeling, and applications

CERN Document Server

de With, Gijsbertus

2013-01-01

For many processes and applications in science and technology a basic knowledge of liquids and solutions is a must. Gaining a better understanding of the behavior and properties of pure liquids and solutions will help to improve many processes and to advance research in many different areas. This book provides a comprehensive, self-contained and integrated survey of this topic and is a must-have for many chemists, chemical engineers and material scientists, ranging from newcomers in the field to more experienced researchers. The author offers a clear, well-structured didactic approach and provides an overview of the most important types of liquids and solutions. Special topics include chemical reactions, surfaces and phase transitions. Suitable both for introductory as well as intermediate level as more advanced parts are clearly marked. Includes also problems and solutions.

Characterisation of long-lived low and intermediate-level radioactive wastes in the Nordic Countries

International Nuclear Information System (INIS)

Broden, K.; Carugati, S.; Brodersen, K.; Carlsson, T.; Viitanen, P.; Walderhaug, T.; Sneve, M.; Hornkjoel, S.; Backe, S.

1997-11-01

The present report is final report from a study on characterisation of radioactive waters in the Nordic countries. The study has mainly been focused on long-lived low and intermediate level radioactive waste. Methods to measure or estimate the activity content and the general composition are discussed. Recommendations are given regarding characterisation of waste under treatment and characterisation of already produced waste packages. (au)

Characterisation of long-lived low and intermediate-level radioactive wastes in the Nordic Countries

Energy Technology Data Exchange (ETDEWEB)

Broden, K. [Studsvik RadWaste AB, (El Salvador); Carugati, S.; Brodersen, K. [Forskningscenter Risoe, (Denmark); Carlsson, T.; Viitanen, P. [VVT, (Finland); Walderhaug, T. [Icelandic Radiation Protection Institute (Iceland); Sneve, M.; Hornkjoel, S. [Norwegian Radiation Protection Authority (Norway); Backe, S. [Institute for Energy Technology (Norway)

1997-11-01

The present report is final report from a study on characterisation of radioactive waters in the Nordic countries. The study has mainly been focused on long-lived low and intermediate level radioactive waste. Methods to measure or estimate the activity content and the general composition are discussed. Recommendations are given regarding characterisation of waste under treatment and characterisation of already produced waste packages. (au).

Six-year experiences in the operation of a low level liquid waste treatment plant

International Nuclear Information System (INIS)

Wen, S.-J.; Hwang, S.-L.; Tsai, C.-M.

1980-01-01

The operation of a low level liquid waste treatment plant is described. The plant is designed for the disposal of liquid waste produced primarily by a 40 MW Taiwan Research Reactor as well as a fuel fabrication plant for the CANDU type reactor and a radioisotopes production laboratory. The monthly volume treated is about 600-2500 ton of low level liquid waste. The activity levels are in the range of 10 -5 -10 -3 μCi/cm 3 . The continuous treatment system of the low level liquid waste treatment plant and the treatment data collected since 1973 are discussed. The advantages and disadvantages of continuous and batch processes are compared. In the continuous process, the efficiency of sludge treatment, vermiculite ion exchange and the adsorption of peat are investigated for further improvement. (H.K.)

Continuous liquid level monitoring sensor system using fiber Bragg grating

Science.gov (United States)

Sengupta, Dipankar; Kishore, Putha

2014-01-01

The design and packaging of simple, small, and low cost sensor heads, used for continuous liquid level measurement using uniformly thinned (etched) optical fiber Bragg grating (FBG) are proposed. The sensor system consists of only an FBG and a simple detection system. The sensitivity of sensor is found to be 23 pm/cm of water column pressure. A linear optical fiber edge filter is designed and developed for the conversion of Bragg wavelength shift to its equivalent intensity. The result shows that relative power measured by a photo detector is linearly proportional to the liquid level. The obtained sensitivity of the sensor is nearly -15 mV/cm.

Corrosion of steel drums containing simulated radioactive waste of low and intermediate level

International Nuclear Information System (INIS)

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

2013-01-01

Ion-exchange resins are frequently used during the operation of nuclear power plants and constitute radioactive waste of low and intermediate level. For the final disposal inside the repository the resins are immobilized by cementation and placed inside steel drums. The eventful contamination of the resins with aggressive species may cause corrosion problems to the drums. In order to assess the incidence of this phenomenon and to estimate the lifespan of the steel drums, in the present work, the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins contaminated with different aggressive species was studied. The aggressive species studied were chloride ions (main ionic species of concern) and sulphate ions (produced during radiolysis of the cationic exchange-resins after cementation). The corrosion rate of the steel was monitored over a time period of 900 days and a chemical and morphological analysis of the corrosion products formed on the steel in each condition was performed. When applying the results obtained in the present work to estimate the corrosion depth of the drums containing the cemented radioactive waste after a period of 300 years (foreseen durability of the Low and Intermediate Level Radioactive Waste facility in Argentina), it was found that in the most unfavourable case (high chloride contamination), the corrosion penetration will be considerably lower than the thickness of the wall of the steel drums. (author)

A Float Type Liquid Level Measuring System Using a Modified Inductive Transducer

Directory of Open Access Journals (Sweden)

Samik MARICK

2014-11-01

Full Text Available Float type liquid level sensor is generally used as a very simple technique for local level indication and level switching. In the present paper a technique has been proposed to transmit the measured liquid level signal of a float type sensor at remote terminal using a modified differential inductance type electromechanical transducer. The theoretical characteristic equation of this transducer has been derived. A prototype unit of the transducer has been developed and fabricated and its performance characteristic has been experimentally determined. The experimental results are reported in the paper. From experimental data, a very good linear characteristic of the proposed level transducer has been observed.

International co-ordinated research project on low and intermediate level waste package performance

Energy Technology Data Exchange (ETDEWEB)

Dayal, R. [International Atomic Energy Agency IAEA, Vienna (Austria)

2001-07-01

As part of IAEA's mandate to facilitate the transfer and exchange of information amongst Member States, the Agency is currently coordinating an international R and D project, involving 12 developed and developing countries, on Performance of Low and Intermediate Level Waste Packages under Disposal Conditions. This paper will review the current status of the Coordinated Research Project (CRP) and summarize the key findings of the work completed to date within the context of the CRP in the participating Member States. (author)

International co-ordinated research project on low and intermediate level waste package performance

International Nuclear Information System (INIS)

Dayal, R.

2001-01-01

As part of IAEA's mandate to facilitate the transfer and exchange of information amongst Member States, the Agency is currently coordinating an international R and D project, involving 12 developed and developing countries, on Performance of Low and Intermediate Level Waste Packages under Disposal Conditions. This paper will review the current status of the Coordinated Research Project (CRP) and summarize the key findings of the work completed to date within the context of the CRP in the participating Member States. (author)

Central repository for low- and intermediate-level waste (ALMA) conceptual design, siting and safety study

International Nuclear Information System (INIS)

Kjellbert, N.; Haeggblom, H.; Cederstroem, M.; Lundgren, T.

1980-07-01

A generic design, siting and safety study of a proposed repository for low- and intermediate-level waste has been made. Special emphasis has been placed on safety characterostics. The conceptual design and the generic site, on which the study is based, are realistically chosen in accordance with present construction techniques and the existing geohydrological conditions in Sweden. (Auth.)

Study of Radiation Shielding Analysis for Low-Intermediate Level Waste Transport Ship

Energy Technology Data Exchange (ETDEWEB)

Kim, Dohyung; Lee, Unjang; Song, Yangsoo; Kim, Sukhoon; Ko, Jaehoon [Korea Nuclear Engineering and Service Corporation, Seoul (Korea, Republic of)

2007-07-01

In Korea, it is planed to transport Low-Intermediate Level Radioactive Waste (LILW) from each nuclear power plant site to Kyongju LILW repository after 2009. Transport through the sea using ship is one of the most prospective ways of LILW transport for current situation in Korea. There are domestic and international regulations for radiation dose limit for radioactive material transport. In this article, radiation shielding analysis for LILW transport ship is performed using 3-D computer simulation code, MCNP. As a result, the thickness and materials for radiation shielding walls next to cargo in the LILW transport ship are determined.

The duration of the institutional controls on the low and intermediate level waste repositories

International Nuclear Information System (INIS)

Yang Jie; Li Yang; Liu Yafang; Lian Bing; Zhao Yangjun; Chen Hailong; Gu Zhijie

2014-01-01

Appropriate institutional controls are put in place prior to repository closure. Such controls can guarantee the long term safety of the repository. Today there is no clear standard on how to determine the institutional control period. This paper tries to give possible factors and activities of the institutional controls on the low and intermediate level waste repositories, and makes some suggestions on the institutional controls in our country. (authors)

Single uniform FBG for simultaneous measurement of liquid level and temperature

International Nuclear Information System (INIS)

Shu, Xuewen; Sugden, Kate; Bennion, Ian

2010-01-01

In this paper, we propose and demonstrate a novel scheme for simultaneous measurement of liquid level and temperature based on a simple uniform fiber Bragg grating (FBG) by monitoring both the short-wavelength-loss peaks and its Bragg resonance. The liquid level can be measured from the amplitude changes of the short-wavelength-loss peaks, while temperature can be measured from the wavelength shift of the Bragg resonance. Both theoretical simulation results and experimental results are presented. Such a scheme has some advantages including robustness, simplicity, flexibility in choosing sensitivity and simultaneous temperature measurement capability

[Blood levels of homocysteine by high pressure liquid chromatography and comparison with two other techniques].

Science.gov (United States)

Ceppa, F; Drouillard, I; Chianea, D; Burnat, P; Perrier, F; Vaillant, C; El Jahiri, Y

1999-01-01

Cardio-vascular diseases are the most common cause of death in industrialized countries. A new marker has emerged among offending risk factors in the past few years: homocysteine. This sulphured amino-acid is an important intermediate in transsulphuration and remethylation reactions of methionine's metabolism. We proposed to evaluate a home made method of determination for this parameter by high performance liquid chromatography (HPLC) and to compare it to fluorescence polarization immunoassay technique (FPIA) and to gaz phase chromatography (CG-SM). This method associated with good sensibility and precision remain much less expensive than FPIA technique.

Management of low- and intermediate level waste in Sweden

International Nuclear Information System (INIS)

Carlsson, Jan

1999-01-01

This presentation describes how the management of radioactive waste is organised in Sweden, where Swedish law places the responsibility for such management with the waste generators. The four nuclear utilities have formed a joint company, the Swedish Nuclear Fuel and Waste Management Co., SKB, to handle the nuclear waste. The Swedish waste management system includes a final repository for short-lived low level waste (LLW) and intermediate level waste (ILW) and an interim storage facility for spent nuclear fuel and long-lived waste. Some very low-level, short-lived waste is disposed of in shallow-land repositories at the nuclear power stations. The final repository is situated in underground rock caverns close to the Forsmark nuclear power plant. The rock caverns have been excavated to a depth of more than 50 m beneath the Baltic Sea floor. LLW is compacted into bales or packaged in metal drums or cases that can be transported in standard freight containers. Radioactive materials used in other sectors such as hospitals are collected and packaged at Studsvik and later deposited in the deep repository. ILW is mixed with cement or bitumen and cast in cement or steel boxes or metal drums. The final repository has different chambers for different kinds of waste. The environmental impact of the repository is negligible. Because Sweden's nuclear power plants and the SKB facilities all are located on the coast, all the waste transport can be conducted by sea. The costs of managing and disposing of Sweden's nuclear waste are small compared to the price of electricity

[Supporting the intermediate level of health care in urban health areas in Kinshasa (1995-2005), DR Congo].

Science.gov (United States)

Mbeva, Jean-Bosco Kahindo; Schirvel, Carole; Karemere, Hermès; Porignon, Denis

2012-06-08

As a result of the decentralization of health systems, some countries have introduced intermediate (provincial) levels in their public health system. This paper presents the results of a case study conducted in Kinshasa on health system decentralization. The study identified a shift from a focus on regulation compliance assessment to an emphasis on health system coordination and health district support. It also highlighted the emergence of a?managerial (as opposed to a bureaucratic) approach to health district support. The performance of health districts in terms of health care coverage and health service use were also found to have improved. The results highlight the importance of intermediate levels in?the health care system and the value of a more organic and managerial rationality in supporting health districts faced with the complexity of urban environments and the integration of specialized multi-partner programs and interventions.

ESP AS A CHALLENGE TO CONFRONT – A CASE STUDY OF TECHNICAL ENGLISH IN A PRE-INTERMEDIATE LEVEL UNIVERSITY CLASSROOM

Directory of Open Access Journals (Sweden)

LUSTIGOVÁ, Lenka

2013-12-01

Full Text Available Drowned in explosive amounts of information, new technology developments, globalisation, international job opportunities and large-scale job migration, ESP courses are faced with the increasing requirement of tailoring language-learning to accommodate employer/employee specialisations. This dynamism is currently being transmitted to courses at the university level, along with the accompanying challenges for all involved. This paper reviews these potential barriers to implementation of ESP courses for students with low proficiency of English, taking a pre-intermediate-level Technical English course at the Czech University of Life Sciences Prague as a case study. After analysing various scholarly references aimed at ESP, the classroom-based research for this paper confirms the feasibility and efficacy of implementing ESP and TE, in particular, even into pre-intermediate classrooms. The self-motivating design of 6 TASKS, as well as authentic video sessions, combined with a student survey and teacher observations, all serve to point to ESP introduction on the pre-intermediate level as achievable in terms of application and resourceful regarding future life-career situations in which students will eventually find themselves.

Programmable System-on-Chip (PSoC) Embedded Readout Designs for Liquid Helium Level Sensors.

Science.gov (United States)

Parasakthi, C; Gireesan, K; Usha Rani, R; Sheela, O K; Janawadkar, M P

2014-08-01

This article reports the development of programmable system-on-chip (PSoC)-based embedded readout designs for liquid helium level sensors using resistive liquid vapor discriminators. The system has been built for the measurement of liquid helium level in a concave-bottomed, helmet-shaped, fiber-reinforced plastic cryostat for magnetoencephalography. This design incorporates three carbon resistors as cost-effective sensors, which are mounted at desired heights inside the cryostat and were used to infer the liquid helium level by measuring their temperature-dependent resistance. Localized electrical heating of the carbon resistors was used to discriminate whether the resistor is immersed in liquid helium or its vapor by exploiting the difference in the heat transfer rates in the two environments. This report describes a single PSoC chip for the design and development of a constant current source to drive the three carbon resistors, a multiplexer to route the sensor outputs to the analog-to-digital converter (ADC), a buffer to avoid loading of the sensors, an ADC for digitizing the data, and a display using liquid crystal display cum light-emitting diode modules. The level sensor readout designed with a single PSoC chip enables cost-effective and reliable measurement system design. © 2014 Society for Laboratory Automation and Screening.

Comparison of bitumen and cement immobilization of intermediate- and low-level radioactive waste

International Nuclear Information System (INIS)

Voss, J.W.

1979-01-01

This paper discusses a systems comparison of two available immobilization processes for intermediate- and low-level radioactive wastes -- bitumen and cement. This study examines a conceptual coprocessed UO 2 - PuO 2 fuel cycle. Radioactive wastes are generated at each stage of this fuel cycle. This study focuses on these transuranic (TRU) wastes generated at a conceptual Fuel Coprocessing Facility. In this report, these wastes are quantified, the immobilization systems conceptualized to process these wastes are presented, and a comparison of the systems is made

Technical factors in the site selection for a radioactive wastes storage of low and intermediate level

International Nuclear Information System (INIS)

Badillo A, V. E.; Ramirez S, J. R.; Palacios H, J. C.

2009-10-01

The storage on surface or near surface it is viable for wastes of low and intermediate level which contain radio nuclides of short half life that would decay at insignificant levels of radioactivity in some decades and also radio nuclides of long half life but in very low concentrations. The sites selection, for the construction of radioactive waste storages, that present an appropriate stability at long term, a foreseeable behavior to future and a capacity to fulfill other operational requirements, is one of the great tasks that confront the waste disposal agencies. In the selection of potential sites for the construction of a radioactive wastes storage of low and intermediate level, several basic judgments should be satisfied that concern to physiography, climatology, geologic, geo-hydrology, tectonic and seismic aspects; as well as factors like the population density, socioeconomic develops and existent infrastructure. the necessary technician-scientific investigations for the selection of a site for the construction of radioactive waste storages are presented in this work and they are compared with the pre-selection factors realized in specify areas in previous studies in different regions of the Mexican Republic. (Author)

Holistic oil field value management: using system dynamics for 'intermediate level' and 'value-based' modelling in the oil industry

International Nuclear Information System (INIS)

Corben, D.; Stevenson, R.; Wolstenholme, E.F.

1999-01-01

System dynamics has been seen primarily as a strategic tool, most effectively used at the highest level of strategy to identify robust policy interventions under a wide range of scenarios. However, an alternative, complementary and powerful role is emerging. This is at an 'intermediate level' in organisations to coordinate and integrate policies across the value chain. It is at this level where business value, as defined by the discounted value of future free cash flow, is both created and destroyed. This paper introduces the need for 'intermediate-level' and 'value-based' modelling and emphasises the natural role of system dynamics in supporting a methodology to fulfil the need. It describes the development of an approach and its application in the oil industry to coordinate the response of people and tools within operational, financial and commercial functions across the value chain to address a variety of problems and issues. (author)

Language in use intermediate : self-study workbook

CERN Document Server

Doff, Adrian

1994-01-01

Each of the four levels comprises about 80 hours of class work, with additional time for the self-study work. The Teacher's Book contains all the pages from the Classroom Book, with interleaved teaching notes including optional activities to cater for different abilities. There is a video to accompany the Beginner, Pre-intermediate and Intermediate levels. Each video contains eight stimulating and entertaining short programmes, as well as a booklet of photocopiable activities. Free test material is available in booklet and web format for Beginner and Pre-intermediate levels. Visit www.cambridge.org/elt/liu or contact your local Cambridge University Press representative.

Transport of Spent Nuclear Fuels, High and Intermediate Level Wastes: A Continuous Challenge

International Nuclear Information System (INIS)

Otton, C.; Blachet, L.

2009-01-01

For more than 45 years TN International has been involved in the radioactive materials transportation field. Since the beginning the used nuclear fuel transportation has been its core business. During all these years TN International, now part of AREVA, has been able to anticipate and fulfil the needs for new transport or storage casks design to fit the nuclear industry evolutions. A whole fleet of casks able to transport all the materials of the nuclear fuel cycle has been developed. In this presentation we will focus on the casks for the spent fuel, high level waste and intermediate level waste transportation. Answering to the constant evolution of the nuclear industry transport needs is a challenge that TN International faces routinely. Concerning the spent nuclear fuel transportation, TN International has developed in the early 80's a fleet of TN12 type casks fitted with several types of baskets able to safely transport all the spent fuel from the nuclear power plant or the research laboratories to AREVA La Hague plant. The current challenge is the design of a new transport cask generation taking into account the needs of the industry for the next 30 years. The replacement of the TN12 cask generation is to be scheduled as the regulations have changed and the fuel characteristics have evolved. The new generation of casks will take into account all the technical evolutions made during the TN12 thirty years of use. MOX spent fuel has now its dedicated cask: the TN112 which certificate of approval has been obtained in July 2008. This cask is able to transport 12 MOX spent fuel elements with a short cooling time. The first loading of the cask has been performed in 2008 in the EDF nuclear power plant of Saint-Laurent-des-Eaux. Concerning the high level waste such as the La Hague vitrified residues a whole fleet of casks has been developed such as the TN 28 VT dedicated to transport, the TN81 and TN85 dedicated to transport and storage. These casks have permitted the

Atomic and electronic structures of an extremely fragile liquid.

Science.gov (United States)

Kohara, Shinji; Akola, Jaakko; Patrikeev, Leonid; Ropo, Matti; Ohara, Koji; Itou, Masayoshi; Fujiwara, Akihiko; Yahiro, Jumpei; Okada, Junpei T; Ishikawa, Takehiko; Mizuno, Akitoshi; Masuno, Atsunobu; Watanabe, Yasuhiro; Usuki, Takeshi

2014-12-18

The structure of high-temperature liquids is an important topic for understanding the fragility of liquids. Here we report the structure of a high-temperature non-glass-forming oxide liquid, ZrO2, at an atomistic and electronic level. The Bhatia-Thornton number-number structure factor of ZrO2 does not show a first sharp diffraction peak. The atomic structure comprises ZrO5, ZrO6 and ZrO7 polyhedra with a significant contribution of edge sharing of oxygen in addition to corner sharing. The variety of large oxygen coordination and polyhedral connections with short Zr-O bond lifetimes, induced by the relatively large ionic radius of zirconium, disturbs the evolution of intermediate-range ordering, which leads to a reduced electronic band gap and increased delocalization in the ionic Zr-O bonding. The details of the chemical bonding explain the extremely low viscosity of the liquid and the absence of a first sharp diffraction peak, and indicate that liquid ZrO2 is an extremely fragile liquid.

Structural analysis of zwitterionic liquids vs. homologous ionic liquids

Science.gov (United States)

Wu, Boning; Kuroda, Kosuke; Takahashi, Kenji; Castner, Edward W.

2018-05-01

Zwitterionic liquids (Zw-ILs) have been developed that are homologous to monovalent ionic liquids (ILs) and show great promise for controlled dissolution of cellulosic biomass. Using both high energy X-ray scattering and atomistic molecular simulations, this article compares the bulk liquid structural properties for novel Zw-ILs with their homologous ILs. It is shown that the significant localization of the charges on Zw-ILs leads to charge ordering similar to that observed for conventional ionic liquids with monovalent anions and cations. A low-intensity first sharp diffraction peak in the liquid structure factor S(q) is observed for both the Zw-IL and the IL. This is unexpected since both the Zw-IL and IL have a 2-(2-methoxyethoxy)ethyl (diether) functional group on the cationic imidazolium ring and ether functional groups are known to suppress this peak. Detailed analyses show that this intermediate range order in the liquid structure arises for slightly different reasons in the Zw-IL vs. the IL. For the Zw-IL, the ether tails in the liquid are shown to aggregate into nanoscale domains.

Studies concerning the degradation of concrete vaults for intermediate-level radioactive waste disposal

International Nuclear Information System (INIS)

Duffo, Gustavo S.; Arva, Esteban A; Giordano, Celia M.; Lafont, Claudio J.

2007-01-01

The National Atomic Energy Commission (CNEA) is the responsible for developing a management nuclear waste disposal programme. This programme contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive wastes. The proposed model is the near-surface monolithic repository similar to those in operation in El Cabril, Spain. The design of this type of repository is based on the use of multiple, independent and redundant barriers. Since the vault and cover are major components of the engineered barriers, the durability of this concrete structures is an important aspect for the facilities integrity. This work presents a laboratory and field investigation performed for the last 6 years on reinforced concrete specimens, in order to predict the service life of the intermediate level radioactive waste disposal vaults from data obtained from electrochemical techniques. On the other hand, the development of sensors that allow on-line measurements of rebar corrosion potential and corrosion current density; incoming oxygen flow that reaches the metal surface; concrete electrical resistivity and chloride concentration is shown. Those sensors, properly embedded in a new full scale vault (nowadays in construction), will allow the monitoring of the corrosion process of the steel rebars embedded in the structure. All the information obtained from the sensors will be used for the final design of the container in order to achieve a service life more or equal than the foreseen durability for this type of facilities. (author) [es

Development of Concentration and Calcination Technology For High Level Liquid Waste

International Nuclear Information System (INIS)

Pande, D.P.

2006-01-01

The concentrated medium and high-level liquid radio chemicals effluents contain nitric acid, water along with the dissolved chemicals including the nitrates of the radio nuclides. High level liquid waste contain mainly nitrates of cesium, strontium, cerium, zirconium, chromium, barium, calcium, cobalt, copper, pickle, iron etc. and other fission products. This concentrated solution requires further evaporation, dehydration, drying and decomposition in temperature range of 150 to 700 deg. C. The addition of the calcined solids in vitrification pot, instead of liquid feed, helps to avoid low temperature zone because the vaporization of the liquid and decomposition of nitrates do not take place inside the melter. In our work Differential and thermo gravimetric studies has been carried out in the various stages of thermal treatment including drying, dehydration and conversion to oxide forms. Experimental studies were done to characterize the chemicals present in high-level radioactive waste. A Rotary Ball Kiln Calciner was used for development of the process because this is amenable for continuous operation and moderately good heat transfer can be achieved inside the kiln. This also has minimum secondary waste and off gases generation. The Rotary Ball Kiln Calciner Demonstration facility system was designed and installed for the demonstration of calcination process. The Rotary Ball Kiln Calciner is a slowly rotating slightly inclined horizontal tube that is externally heated by means of electric resistance heating. The liquid feed is sprayed onto the moving bed of metal balls in a slowly rotating calciner by a peristaltic type-metering pump. The vaporization of the liquid occurs in the pre-calcination zone due to counter current flow of hot gases. The dehydration and denitration of the solids occurs in the calcination zone, which is externally heated by electrical furnace. The calcined powder is cooled in the post calcination portion. It has been demonstrated that the

Design and operation of off-gas cleaning systems at high level liquid waste conditioning facilities

International Nuclear Information System (INIS)

1988-01-01

The immobilization of high level liquid wastes from the reprocessing of irradiated nuclear fuels is of great interest and serious efforts are being undertaken to find a satisfactory technical solution. Volatilization of fission product elements during immobilization poses the potential for the release of radioactive substances to the environment and necessitates effective off-gas cleaning systems. This report describes typical off-gas cleaning systems used in the most advanced high level liquid waste immobilization plants and considers most of the equipment and components which can be used for the efficient retention of the aerosols and volatile contaminants. In the case of a nuclear facility consisting of several different facilities, release limits are generally prescribed for the nuclear facility as a whole. Since high level liquid waste conditioning (calcination, vitrification, etc.) facilities are usually located at fuel reprocessing sites (where the majority of the high level liquid wastes originates), the off-gas cleaning system should be designed so that the airborne radioactivity discharge of the whole site, including the emission of the waste conditioning facility, can be kept below the permitted limits. This report deals with the sources and composition of different kinds of high level liquid wastes and describes briefly the main high level liquid waste solidification processes examining the sources and characteristics of the off-gas contaminants to be retained by the off-gas cleaning system. The equipment and components of typical off-gas systems used in the most advanced (large pilot or industrial scale) high level liquid waste solidification plants are described. Safety considerations for the design and safe operation of the off-gas systems are discussed. 60 refs, 31 figs, 17 tabs

Management of low and intermediate level radioactive wastes with regard to their chemical toxicity

International Nuclear Information System (INIS)

2002-12-01

A preliminary overview is provided of management options for low and intermediate level radioactive waste (LILW) with regard to its chemical toxicity. In particular, the following issues are identified and described associated with the management and safe disposal of chemically toxic materials in LILW: the origin and characteristics; the regulatory approaches; the pre-disposal management; the disposal; the safety assessment. Also included are: regulatory framework for chemically toxic low level wastes in the USA; pre-disposal processing options for LILW containing chemically toxic components; example treatment technologies for LILW containing chemically toxic components and safety assessment case studies for Germany, Belgium, France and Sweden

Implications of long-term surface or near-surface storage of intermediate and low-level wastes in the UK

International Nuclear Information System (INIS)

Murray, N.; Vande Putte, D.; Ware, R.J.

1986-02-01

Various options for 200 year-long storage of all Low- and Intermediate-Level wastes generated to the year 2030 are considered. On-site storage and centralised storage have been examined and compared. The feasibility of storing some of the wastes in underground facilities that are convertible to repositories has been demonstrated, but it is shown that centralised, surface storage of wastes would be more economical. There appears to be little merit in storing Intermediate Level wastes in separate facilities that could be converted to repositories. Storage is shown to be more expensive than direct disposal, except if future costs are discounted by more than about 10%. With carefully designed stores and remote handling, the collective dose to operators could be limited to about 20-40 man Sv over the whole period of storage. (author)

Acid fractionation for low level liquid waste cleanup and recycle

International Nuclear Information System (INIS)

Gombert, D. II; McIntyre, C.V.; Mizia, R.E.; Schindler, R.E.

1990-01-01

At the Idaho Chemical Processing Plant, low level liquid wastes containing small amounts of radionuclides are concentrated via a thermosyphon evaporator for calcination with high level waste, and the evaporator condensates are discharged with other plant wastewater to a percolation pond. Although all existing discharge guidelines are currently met, work has been done to reduce all waste water discharges to an absolute minimum. In this regard, a 15-tray acid fractionation column will be used to distill the mildly acidic evaporator condensates into concentrated nitric acid for recycle in the plant. The innocuous overheads from the fractionator having a pH greater than 2, are superheated and HEPA filtered for atmospheric discharge. Nonvolatile radionuclides are below detection limits. Recycle of the acid not only displaces fresh reagent, but reduces nitrate burden to the environment, and completely eliminates routine discharge of low level liquid wastes to the environment

Elements of banking intermediation in the Algerian Banking system and the means to activate it

Directory of Open Access Journals (Sweden)

Habbar Abderezak, Dr.

2014-06-01

Banking intermediation raises several interrelated issues for banks, the central bank and the Treasury. It is linked to the gross domestic product, money supply and bank liquidity, etc. These elements will be examined in this article to learn the elements of bank intermediation in the Algerian banking system and ways of strengthening it.

Liquid level measurement on coolant pipeline using Raman distributed temperature sensor

International Nuclear Information System (INIS)

Kasinathan, M.; Sosamma, S.; Babu Rao, C.; Murali, N.; Jayakumar, T.

2011-01-01

Optical fibre based Raman Distributed Temperature Sensor (RDTS) has been widely used for temperature monitoring in oil pipe line, power cable and environmental monitoring. Recently it has gained importance in nuclear reactor owing to its advantages like continuous, distributed temperature monitoring and immunity from electromagnetic interference. It is important to monitor temperature based level measurement in sodium capacities and in coolant pipelines for Fast Breeder Reactor (FBR). This particular application is used for filling and draining sodium in storage tank of sodium circuits of Fast breeder reactor. There are different conventional methods to find out the sodium level in the storage tank of sodium cooled reactors. They are continuous level measurement and discontinuous level measurement. For continuous level measurement, mutual inductance type level probes are used. The disadvantage of using this method is it needs a temperature compensation circuit. For discontinuous level measurement, resistance type discontinuous level probe and mutual inductance type discontinuous level probe are used. In resistance type discontinuous level probe, each level needs a separate probe. To overcome these disadvantages, RDTS is used for level measurement based distributed temperature from optical fibre as sensor. The feasibility of using RDTS for measurement of temperature based level measurement sensor is studied using a specially designed test set-up and using hot water, instead of sodium. The test set-up consist of vertically erected Stainless Steel (SS) pipe of length 2m and diameter 10cm, with provision for filling and draining out the liquid. Bare graded index multimode fibre is laid straight along the length of the of the SS pipe. The SS pipe is filled with hot water at various levels. The hot water in the SS pipe is maintained at constant temperature by insulating the SS pipe. The temperature profile of the hot water at various levels is measured using RDTS. The

Special Analysis for Disposal of High-Concentration I-129 Waste in the Intermediate-Level Vaults at the E-Area Low-Level Waste Facility

Energy Technology Data Exchange (ETDEWEB)

Collard, L.B.

2000-09-26

This revision was prepared to address comments from DOE-SR that arose following publication of revision 0. This Special Analysis (SA) addresses disposal of wastes with high concentrations of I-129 in the Intermediate-Level (IL) Vaults at the operating, low-level radioactive waste disposal facility (the E-Area Low-Level Waste Facility or LLWF) on the Savannah River Site (SRS). This SA provides limits for disposal in the IL Vaults of high-concentration I-129 wastes, including activated carbon beds from the Effluent Treatment Facility (ETF), based on their measured, waste-specific Kds.

Special Analysis for Disposal of High-Concentration I-129 Waste in the Intermediate-Level Vaults at the E-Area Low-Level Waste Facility

International Nuclear Information System (INIS)

Collard, L.B.

2000-01-01

This revision was prepared to address comments from DOE-SR that arose following publication of revision 0. This Special Analysis (SA) addresses disposal of wastes with high concentrations of I-129 in the Intermediate-Level (IL) Vaults at the operating, low-level radioactive waste disposal facility (the E-Area Low-Level Waste Facility or LLWF) on the Savannah River Site (SRS). This SA provides limits for disposal in the IL Vaults of high-concentration I-129 wastes, including activated carbon beds from the Effluent Treatment Facility (ETF), based on their measured, waste-specific Kds

Partitioning of high level liquid waste: experiences in plant level adoption

International Nuclear Information System (INIS)

Manohar, Smitha; Kaushik, C.P.

2016-01-01

High Level Radioactive Wastes are presently vitrified in borosilicate matrices in all our back end facilities in our country. This is in accordance with internationally endorsed methodology for the safe management of high level radioactive wastes. Recent advancements in the field of partitioning technology in our group, has presented us with an opportunity to have a fresh perspective on management of high level liquid radioactive wastes streams, that emanate from reprocessing operations. This paper will highlight our experiences with respect to both partitioning studies and vitrification practices, with a focus on waste volume reduction for final disposal. Incorporation of this technique has led to the implementation of the concept of recovering wealth from waste, a marked decrease on the load of disposal in deep geological repositories and serve as a step towards the vision of transmutation of long lived radionuclides

Competition, liquidity and stability: international evidence at the bank and systemic levels

OpenAIRE

Nguyen, Thi Ngoc My

2017-01-01

This thesis investigates the impact of market power on bank liquidity; the association between competition and systemic liquidity; and whether the associations between liquidity and stability at both bank- and systemic- levels are affected by competition. The first research question is explored in the context of 101 countries over 1996-2013 while the second and the third, which require listed banks, use a smaller sample of 32 nations during 2001-2013. The Panel Least Squares and the system Ge...

Review of the microbiological, chemical and radiolytic degradation of organic material likely to be present in intermediate level and low level radioactive wastes

International Nuclear Information System (INIS)

Greenfield, B.F.; Rosevear, A.; Williams, S.J.

1990-11-01

A review has been made of the microbiological, chemical and radiolytic degradation of the solid organic materials likely to be present in intermediate-level and low-level radioactive wastes. Possible interactions between the three routes for degradation are also discussed. Attention is focussed on the generation of water-soluble degradation products which may form complexes with radioelements. The effects of complexation on radioelement solubility and sorption are considered. Recommendations are made for areas of further research. (author)

Intermediate levels of hippocampal activity appear optimal for associative memory formation.

Directory of Open Access Journals (Sweden)

Xiao Liu

Full Text Available BACKGROUND: It is well established that hippocampal activity is positively related to effective associative memory formation. However, in biological systems often optimal levels of activity are contrasted by both sub- and supra-optimal levels. Sub-optimal levels of hippocampal activity are commonly attributed to unsuccessful memory formation, whereas the supra-optimal levels of hippocampal activity related to unsuccessful memory formation have been rarely studied. It is still unclear under what circumstances such supra-optimal levels of hippocampal activity occur. To clarify this issue, we aimed at creating a condition, in which supra-optimal hippocampal activity is associated with encoding failure. We assumed that such supra-optimal activity occurs when task-relevant information is embedded in task-irrelevant, distracting information, which can be considered as noise. METHODOLOGY/PRINCIPAL FINDINGS: In the present fMRI study, we probed neural correlates of associative memory formation in a full-factorial design with associative memory (subsequently remembered versus forgotten and noise (induced by high versus low distraction as factors. Results showed that encoding failure was associated with supra-optimal activity in the high-distraction condition and with sub-optimal activity in the low distraction condition. Thus, we revealed evidence for a bell-shape function relating hippocampal activity with associative encoding success. CONCLUSIONS/SIGNIFICANCE: Our findings indicate that intermediate levels of hippocampal activity are optimal while both too low and too high levels appear detrimental for associative memory formation. Supra-optimal levels of hippocampal activity seem to occur when task-irrelevant information is added to task-relevant signal. If such task-irrelevant noise is reduced adequately, hippocampal activity is lower and thus optimal for associative memory formation.

High performance liquid-level sensor based on mPOFBG for aircraft applications

DEFF Research Database (Denmark)

Marques, C. A. F.; Pospori, A.; Saez-Rodriguez, D.

2015-01-01

A high performance liquid-level sensor based on microstructured polymer optical fiber Bragg grating (mPOFBG) array sensors is reported in detail. The sensor sensitivity is found to be 98pm/cm of liquid, enhanced by more than a factor of 9 compared to a reported silica fiber-based sensor....

Heat exchanger with intermediate evaporating and condensing fluid

International Nuclear Information System (INIS)

Fraas, A.P.

1978-01-01

A shell and tube-type heat exchanger, such as a liquid sodium-operated steam generator for use in nuclear reactors, comprises a shell containing a primary fluid tube bundle, a secondary fluid tube bundle at higher elevation, and an intermediate fluid vaporizing at the surface of the primary fluid tubes and condensing at the surface of the secondary fluid tubes

Modified dispersive liquid-liquid microextraction for pre-concentration of benzene, toluene, ethylbenzene and xylenes prior to their determination by GC

International Nuclear Information System (INIS)

Faraji, Hakim; Feizbakhsh, Alireza; Helalizadeh, Masoumeh

2013-01-01

We have developed a modified method for the extraction and preconcentration of benzene, toluene, ethylbenzene and xylenes (BTEX) in aqueous samples. It based on dispersive liquid-liquid microextraction along with solidification of floating organic microdrops. The dispersion of microvolumes of an extracting solvent into the aqueous occurs without dispersive solvent. Various parameters have been optimized. BTEX were quantified via GC with FID detection. Under optimized conditions, the preconcentration factors range from 301 to 514, extraction efficiencies from 60 to 103 %, repeatabilities from 2.2 to 4.1 %, and intermediate precisions from 3.5 to 7.0 %. The relative recovery for each analyte in water samples at three spiking levels is >85.6 %, with a relative standard deviation of <7.4 %. (author)

Aspects of chemistry in management of radioactive liquid wastes from nuclear installations

International Nuclear Information System (INIS)

Yeotikar, R.G.

2007-01-01

Nuclear energy is the only source available to the mankind to fulfill the continuous and ever increasing demand of energy. The public acceptance and popularity of nuclear energy depends to a large extent on management of radioactive waste. The nuclear waste management demands eco-friendly process/systems. This article highlights the sources of different types of radioactive liquid wastes generated in the nuclear installation and their treatment process. The radioactive liquid waste is classified mainly into three categories based on activity levels e.g. low, intermediate and high level. The management of radioactive liquid waste is very critical because of its 'mobility and liquid' nature. Secondly the liquid wastes have wide range of activity and chemistry spectrum and their volumes are also different. Hence the methods for management of different types of liquid wastes are also different. Mostly the treatment and conditioning processes are chemical processes. The chemistry involved in the treatment and conditioning of these wastes, problems related with chemistry for each processes and efforts to solve these problems, aspects of adoption on plant scale, etc., have been discussed in this article. (author)

Bireactor Electronuclear Systems with Liquid Cadmium Valve

CERN Document Server

Bznuni, S A; Zhamkochyan, V M; ASosnin, A N; Polanski, A; Khudaverdyan, A H

2002-01-01

Three main types of bireactor electronuclear systems are discussed. From the point of view of assuring high level of functional characteristics and safety bireactor electronuclear systems with booster using enriched uranium (20 %) and with a liquid cadmium valve appears to be the most effective. It is shown by means of Monte-Carlo modeling that such operation conditions can be achieved which lead to the destruction of the intermediate cadmium layer making the systems supercritical (k_{eff}>1). One can avoid the problem by using a special design of the liquid cadmium valve. In comparison with other nuclear systems (critical reactors, one-reactor electronuclear systems) cascade electronuclear systems have essential advantages allowing the decrease of the proton beam current by one order of magnitude and providing at same time the necessary level of power generation and neutron flux. Availability of both the thermal and fast cones allows one to transmute not only transuranics but also the fission products - cesi...

Filtration of Oak Ridge National Laboratory simulated liquid low-level waste

International Nuclear Information System (INIS)

Fowler, V.L.; Hewitt, J.D.

1989-08-01

A method for disposal of Oak Ridge National Laboratory's (ORNL's) liquid low-level radioactive waste (LLLW) is being developed in which the material will be solidified in cement and stored in an aboveground engineered storage facility. The acceptability of the final waste form rests in part on the presence or absence of transuranic isotopes. Filtration methods to remove transuranic isotopes from the bulk liquid stored in the Melton Valley Storage Tanks (MVST) were investigated in this study. Initial batch studies using waste from MVST indicate that >99.9% of the transuranic isotopes can be removed from the bulk liquid by simple filtration. Bench-scale studies with a nonradioactive surrogate waste indicate that >99.5% of the suspended solids can be removed from the bulk liquid via inertial crossflow filtration. 4 refs., 3 figs., 11 tabs

Norwegian work on establishing a combined storage and disposal facility for low and intermediate level waste

International Nuclear Information System (INIS)

International Atomic Energy Agency WATRP Review Team.

1995-12-01

The IAEA has, through its Waste Management Assessment and Technical Review Programme (WATRP), evaluated policies and facilities related to management of radioactive waste in Norway. It is concluded that the Himdalen site, in combination with the chosen engineering concept, can be suitable for the storage and disposal of the relatively small amounts of Norwegian low and intermediate level waste

The influence of organic materials on the near field of an intermediate level radioactive waste repository

International Nuclear Information System (INIS)

Wilkins, J.D.

1988-01-01

The influence of organic materials which are present in some intermediate level wastes on the chemistry of the near field of a radioactive waste repository is discussed. Particular attention is given to the possible formation of water soluble complexing agents as a result of the radiation field and chemical conditions. The present state of the research is reviewed. (author)

Use of the mixture of clay and crushed rock as a backfill material for low and intermediate level radioactive waste repository. Appendix 10: Republic of Korea

International Nuclear Information System (INIS)

Cho, W.J.; Lee, J.O.; Hahn, P.S.; Chun, K.S.

2001-01-01

At the time of the CRP, a repository for low and intermediate level radioactive wastes arising from nuclear power plant operation and radioisotope application in the Republic of Korea was to be constructed in the bedrock below ground surface. As the intermediate level waste cavern would contain the major part of radionuclide inventory in the cavern, the radionuclide release from the intermediate level waste cavern was therefore important from the viewpoint of disposal facility performance. The then current design concept suggested that the intermediate level waste would be emplaced into the compartment made of reinforced concrete, and the space between the concrete wall and cavern surface would be backfilled with a clay-based material. As compacted clay-based materials have a low hydraulic conductivity and the hydraulic gradient in a disposal cavern was expected to be relatively low, molecular diffusion was considered to be the principal mechanism by which radionuclides would migrate through the backfill. The mixture of calcium bentonite and crushed rock was being suggested as a candidate backfill material. This appendix summarises the KAERI research activities on the evaluation of hydraulic conductivity, radionuclide diffusion coefficient, and mechanical properties of the candidate clay-based backfill material for the intermediate level waste cavern

Geological evaluation of spent fuel storage and low-intermediate level radwaste disposal in the site of NPP candidate

International Nuclear Information System (INIS)

Sucipta; Yatim, S.; Martono, H.; Pudyo, A.

1997-01-01

Based on the consideration of techno-economy and environmental safety, the radioactive waste treatment installation (RWI), interim storage of spen fuel (ISSF) and low-intermediate level disposal shall be sited in the surrounding of NPP area. The land suitability of NPP's site candidate at Muria Peninsula as spent fuel storage and low-intermediate level radwaste disposal need to be studied. Site selection was conducted by overlay method and scoring method, and based on safety criteria which include geological and environmental aspects. Land evaluation by overlay method has given result a potential site which have highest suitable land at surrounding of borehole L-15 about 17.5 hectares. Land evaluation by scoring method has given result two land suitability classes, i.e. moderate suitability class (includes 14 borehole) and high suitability class, include borehole L-2, L-14 and L-15 (author)

Multifragmentation in intermediate energy heavy ion collisions

International Nuclear Information System (INIS)

Jacak, B.V.; Britt, H.C.; Claesson, G.

1986-01-01

There has been considerable recent interest in the production of intermediate mass fragments (A > 4) in intermediate and high energy nucleus-nucleus collisions. The mechanism for production of these fragments is not well understood and has been described by models employing a variety of assumptions. Some examples are: disassembly of a system in thermal equilibrium into nucleons and nuclear fragments, liquid-vapor phase transitions in nuclear matter, final state coalescence of nucleons and dynamical correlations between nucleons at breakup. Previous studies of fragment production, with one exception, have been single particle inclusive measurements; the observed fragment mass (or charge) distributions can be described by all of the models above. To gain insight into the fragment production mechanism, the authors used the GSI/LBL Plastic Ball detector system to get full azimuthal coverage for intermediate mass fragments in the forward hemisphere in the center of mass system while measuring all the light particles in each event. The authors studied the systems 200 MeV/nucleon Au + Au and Au + Fe

An investigation of core liquid level depression in small break loss-of-coolant accidents

International Nuclear Information System (INIS)

Schultz, R.R.; Watkins, J.C.; Motley, F.E.; Stumpf, H.; Chen, Y.S.

1991-08-01

Core liquid level depression can result in partial core dryout and heatup early in a small break loss-of-coolant accident (SBLOCA) transient. Such behavior occurs when steam, trapped in the upper regions of the reactor primary system (between the loop seal and the core inventory), moves coolant out of the core region and uncovers the rod upper elevations. The net result is core liquid level depression. Core liquid level depression and subsequent core heatups are investigated using subscale data from the ROSA-IV Program's 1/48-scale Large Scale Test Facility (LSTF) and the 1/1705-scale Semiscale facility. Both facilities are Westinghouse-type, four-loop, pressurized water reactor simulators. The depression phenomena and factors which influence the minimum core level are described and illustrated using examples from the data. Analyses of the subject experiments, conducted using the TRAC-PF1/MOD1 (Version 12.7) thermal-hydraulic code, are also described and summarized. Finally, the response of a typical Westinghouse four-loop plant (RESAR-3S) was calculated to qualitatively study coal liquid level depression in a full-scale system. 31 refs., 37 figs., 6 tabs

Results of intermediate-scale hot isostatic press can experiments

International Nuclear Information System (INIS)

Nelson, L.O.; Vinjamuri, K.

1995-05-01

Radioactive high-level waste (HLW) has been managed at the Idaho Chemical Processing Plant (ICPP) for a number of years. Since 1963, liquid HLW has been solidified into a granular solid (calcine). Presently, over 3,800 m 3 of calcine is stored in partially-underground stainless steel bins. Four intermediate- scale HLW can tests (two 6-in OD x 12-in tall and two 4-in OD x 7-in tall) are described and compared to small-scale HIP can tests (1- to 3-in OD x 1- to 4.5-in tall). The intermediate-scale HIP cans were loaded with a 70/30 calcine/frit blend and HIPped at an off-site facility at 1050 degrees C; and 20 ksi. The dimensions of two cans (4-in OD x 7-in tall) were monitored during the HIP cycle with eddy-current sensors. The sensor measurements indicated that can deformation occurs rapidly at 700 degrees C; after which, there is little additional can shrinkage. HIP cans were subjected to a number of analyses including calculation of the overall packing efficiency (56 to 59%), measurement of glass-ceramic (3.0 to 3.2 g/cc), 14-day MCC-1 leach testing (total mass loss rates 2 day), and scanning electron microscopy (SEM). Based on these analyses, the glass-ceramic material produced in intermediate-scale cans is similar to material produced in small-scale cans. No major scale-up problems were indicated. Based on the packing efficiency observed in intermediate- and small-scale tests, the overall packing efficiency of production-scale (24-in OD x 36- to 190-in tall) cans would be approximately 64% for a pre-HIP right-circular cylinder geometry. An efficiency of 64% would represent a volume reduction factor of 2.5 over a candidate glass waste prepared at 33 wt% waste loading

Stabilization and isolation of low-level liquid waste disposal sites

International Nuclear Information System (INIS)

Phillips, S.J.; Gilbert, T.W.

1987-01-01

Rockwell Hanford Operations is developing and testing equipment for stabilization and isolation of low-level radioactive liquid waste disposal sites. Stabilization and isolation are accomplished by a dynamic consolidation and particulate grout injection system. System equipment components include: a mobile grout plant for transport, mixing, and pumping of particulate grout; a vibratory hammer/extractor for consolidation of waste, backfill, and for emplacement of the injector; dynamic consolidation/injector probe for introducing grout into fill material; and an open-void surface injector that uses surface or subsurface mechanical or pneumatic packers and displacement gas filtration for introducing grout into disposal structure access piping. Treatment of a liquid-waste disposal site yields a physically stable, cementitious monolith. Additional testing and modification of this equipment for other applications to liquid waste disposal sites is in progress

Research and Development of Solar Evaporation on Low Level Radioactive Liquid Waste

Directory of Open Access Journals (Sweden)

ZHANG Hua

2016-02-01

Full Text Available Solar evaporation, which can save energy and obtain the higher decontamination factor, the larger treatment capability with the simpler designed and easy operation, was one of the general methods to treat low level radioactive liquid waste. However, the use of solar evaporation was limited because the facilities had to occupy the larger area and require sunshine for the longer duration, etc. Several cases form USA, Australian, India and South Korea were presented on R&D of solar evaporation to treat low level radioactive liquid waste.

Interpretation and code generation based on intermediate languages

DEFF Research Database (Denmark)

Kornerup, Peter; Kristensen, Bent Bruun; Madsen, Ole Lehrmann

1980-01-01

The possibility of supporting high level languages through intermediate languages to be used for direct interpretation and as intermediate forms in compilers is investigated. An accomplished project in the construction of an interpreter and a code generator using one common intermediate form...

An optical liquid level sensor based on core-offset fusion splicing method using polarization-maintaining fiber

Science.gov (United States)

Lou, Weimin; Chen, Debao; Shen, Changyu; Lu, Yanfang; Liu, Huanan; Wei, Jian

2016-01-01

A simple liquid level sensor using a small piece of hydrofluoric acid (HF) etched polarization maintaining fiber (PMF), with SMF-PMF-SMF fiber structure based on Mach- Zehnder interference (MZI) mechanism is proposed. The core-offset fusion splicing method induced cladding modes interfere with the core mode. Moreover, the changing liquid level would influence the optical path difference of the MZI since the effective refractive indices of the air and the liquid is different. Both the variations of the wavelength shifts and power intensity attenuation corresponding to the liquid level can be obtained with a sensitivity of 0.4956nm/mm and 0.2204dB/mm, respectively.

Melton Valley liquid low-level radioactive waste storage tanks evaluation

International Nuclear Information System (INIS)

1995-06-01

The Melton Valley Liquid Low-Level Radioactive Waste Storage Tanks (MVSTs) store the evaporator concentrates from the Liquid Low-Level Radioactive Waste (LLLW) System at the Oak Ridge National Laboratory (ORNL). The eight stainless steel tanks contain approximately 375,000 gallons of liquid and sludge waste. These are some of the newer, better-designed tanks in the LLLW System. They have been evaluated and found by the US Environmental Protection Agency (EPA) and the Tennessee Department of Environment and Conservation to comply with all Federal Facility Agreement requirements for double containment. The operations and maintenance aspects of the tanks were also reviewed by the Defense Nuclear Facilities Safety Board (DNFSB) in September 1994. This document also contains an assessment of the risk to the public and ORNL workers from a leak in one of the MVSTs. Two primary scenarios were investigated: (1) exposure of the public to radiation from drinking Clinch River water contaminated by leaked LLLW, and (2) exposure of on-site workers to radiation by inhaling air contaminated by leaked LLLW. The estimated frequency of a leak from one of the MVSTs is about 8 x 10 -4 events per year, or about once in 1200 years (with a 95% confidence level). If a leak were to occur, the dose to a worker from inhalation would be about 2.3 x 10 -1 mrem (with a 95% confidence level). The dose to a member of the public through the drinking water pathway is estimated to be about 7 x 10 -1 mrem (with a 95% confidence level). By comparison with EPA Safe Drinking Water regulations, the allowable lifetime radiation dose is about 300 mrem. Thus, a postulated LLLW leak from the MVSTs would not add appreciably to an individual's lifetime radiation dose

A Simple Treatment of the Liquidity Trap for Intermediate Macroeconomics Courses

Science.gov (United States)

Buttet, Sebastien; Roy, Udayan

2014-01-01

Several leading undergraduate intermediate macroeconomics textbooks now include a simple reduced-form New Keynesian model of short-run dynamics (alongside the IS-LM model). Unfortunately, there is no accompanying description of how the zero lower bound on nominal interest rates affects the model. In this article, the authors show how the…

Numerical simulation on stir system of jet ballast in high level liquid waste storage tank

International Nuclear Information System (INIS)

Lu Yingchun

2012-01-01

The stir system of jet ballast in high level liquid waste storage tank was simulation object. Gas, liquid and solid were air, sodium nitrate liquor and titanium whitening, respectively. The mathematic model based on three-fluid model and the kinetic theory of particles was established for the stir system of jet ballast in high level liquid waste storage tank. The CFD commercial software was used for solving this model. The detail flow parameters as three phase velocity, pressure and phase loadings were gained. The calculated results agree with the experimental results, so they can well define the flow behavior in the tank. And this offers a basic method for the scale-up and optimization design of the stir system of jet ballast in high level liquid waste storage tank. (author)

Electronic circuit provides automatic level control for liquid nitrogen traps

Science.gov (United States)

Turvy, R. R.

1968-01-01

Electronic circuit, based on the principle of increased thermistor resistance corresponding to decreases in temperature provides an automatic level control for liquid nitrogen cold traps. The electronically controlled apparatus is practically service-free, requiring only occasional reliability checks.

Trauma surgeon becomes consultant: evaluation of a protocol for management of intermediate-level trauma patients.

Science.gov (United States)

Fallon, Sara C; Delemos, David; Christopher, Daniel; Frost, Mary; Wesson, David E; Naik-Mathuria, Bindi

2014-01-01

At our level 1 pediatric trauma center, 9-54 intermediate-level ("level 2") trauma activations are received per month. Previously, the surgery team was required to respond to and assume responsibility for all patients who had "level 2" trauma activations. In 8/2011, we implemented a protocol where the emergency room (ER) physician primarily manages these patients with trauma consultation for surgical evaluation or admission. The purpose of this study was to prospectively evaluate the effects of the new protocol to ensure that patient safety and quality of care were maintained. We compared outcomes of patients treated PRE-implementation (10/2010-7/2011) and POST-implementation (9/2011-5/2012), including surgeon consultation rate, utilization of imaging and laboratory testing, ER length of stay, admission rate, and missed injuries or readmissions. Statistical analysis included chi-square and Student's t-test. We identified 472 patients: 179 in the PRE and 293 in the POST period. The populations had similar baseline clinical characteristics. The surgical consultation rate in the POST period was only 42%, with no missed injuries or readmissions. The ER length of stay did not change. However, in the POST period there were significant decreases in the admission rate (73% to 44%) and the mean number of CT scans (1.4 to 1), radiographs (2.4 to 1.7), and laboratory tests (5.1 to 3.3) ordered in the emergency room (all p<0.001). Intermediate-level pediatric trauma patients can be efficiently and safely managed by pediatric emergency room physicians, with surgical consultation only as needed. The protocol change improved resource utilization by decreasing testing and admissions and streamlining resident utilization in an era of reduced duty hours. © 2014.

Estimation of the conditioning and storage costs of low- and intermediate-level solid radioactive wastes

International Nuclear Information System (INIS)

Lo Moro, A.; Panciatici, G.

1977-01-01

The conditioning and storage costs of low- and intermediate-level solid radioactive wastes are analyzed. The cost of direct labour is assumed as the reference cost for their computation and the storage cost is considered as resulting from the contract cost ''una tantum'' and from the leasing cost. As an example, the cost trends are reported, relevant to the solution adopted at CAMEN (conditioning in concrete containers and storage on concrete open-air bed)

Liquid-gas phase transition and isospin fractionation in intermediate energy heavy ion collisions

International Nuclear Information System (INIS)

Xing Yongzhong; Liu Jianye; Guo Wenjun

2004-01-01

The liquid-gas phase transition in the heavy ion collisions and nuclear matter has been an important topic and got achievements, such as, based on the studies by H.Q. Song et al the critical temperature of liquid-gas phase transition enhances with increasing the mass of system and reduces as the increase of the neutron proton ratio of system. As authors know that both the liquid-gas phase transition and the isospin fractionation occur in the spinodal instability region at the nuclear density below the normal nuclear density. In particular, these two dynamical processes lead to the separation of nuclear matter into the liquid phase and gas phase. In this case to compare their dynamical behaviors is interested. The authors investigate the dependence of isospin fractionation degree on the mass and neutron proton ratio of system by using the isospin dependent quantum molecular dynamics model. The authors found that the degree of isospin fractionation (N/Z) n /(N/Z) imf decreases with increasing the mass of the system. This is just similar to the enhance of the critical temperature of liquid-gas phase transition T c as the increase of system mass. Because the enhance of T c is not favorable for the liquid-gas transition taking place, which reduces the isospin fractionation process and leads to decrease of (N/Z) n /(N/Z) imf . However the degree of isospin fractionation enhances with increasing the neutron proton ratio of the system. It is just corresponding to the reduce of T c of the liquid-gas phase transition as the increase of the isospin fractionation of the system. Because the reduce of T c enhances the liquid-gas phase transition process and also prompts the isospin fractionation process leading the increase of the isospin fractionation degree. To sum up, there are very similar dynamical behaviors for the degree of isospin fractionation and the critical temperature of the liquid-gas phase transition. So dynamical properties of the liquid-gas phase transition can

A new interface weak-capacitance detection ASIC of capacitive liquid level sensor in the rocket

Science.gov (United States)

Yin, Liang; Qin, Yao; Liu, Xiao-Wei

2017-11-01

A new capacitive liquid level sensing interface weak-capacitance detection ASIC has been designed. This ASIC realized the detection of the output capacitance of the capacitive liquid level sensor, which converts the output capacitance of the capacitive liquid level sensor to voltage. The chip is fabricated in a standard 0.5μm CMOS process. The test results show that the linearity of capacitance detection of the ASIC is 0.05%, output noise is 3.7aF/Hz (when the capacitance which will be detected is 40 pF), the stability of capacitance detection is 7.4 × 10-5pF (1σ, 1h), the output zero position temperature coefficient is 4.5 uV/∘C. The test results prove that this interface ASIC can meet the requirement of high accuracy capacitance detection. Therefore, this interface ASIC can be applied in capacitive liquid level sensing and capacitive humidity sensing field.

Risk comparison of different treatment and disposal strategies of high level liquid radioactive waste

International Nuclear Information System (INIS)

Fang Dong

1997-01-01

The risk of different treatment and disposal strategies of high level liquid radioactive waste from spent fuel reprocessing is estimated and compared. The conclusions obtained are that risk difference from these strategies is very small and high level liquid waste can be reduced to middle and low level waste, if the decontamination factor for 99 Tc is large enough, which is the largest risk contributor in the high level radioactive waste from spent fuel reprocessing. It is also shown that the risk of high level radioactive waste could be reduced by the technical strategy of combining partitioning and transmutation

Bicontinuous liquid crystals

CERN Document Server

Lynch, Mathew L

2005-01-01

PrefaceIntroduction AcknowledgmentsBicontinuous Cubic Liquid Crystalline Materials: A Historical Perspective and Modern Assessment; Kr̄e LarssonIntermediate Phases; Michael C. Holmes and Marc S. LeaverCubic Phases and Human Skin: Theory and Practice; Steven Hoath and Lars NorlňThe Relationship between Bicontinuous Inverted Cubic Phases and Membrane Fusion; D.P. SiegelAspects of the Differential Geometry and Topology of Bicontinuous Liquid-Crystalline Phases; Robert W. CorkeryNovel L3 Phases and Their Macroscopic Properties; R. Beck and H. HoffmannBicontinuous Cubic Phases of Lipids with Entra

Measurements of 222Rn and 226Ra Levels in environmental samples by using liquid scintillation counter

International Nuclear Information System (INIS)

Moustafa, A.S.

2004-01-01

The advantageous of liquid scintillation counting technique for 6 Ra determination compared with other methods are the high counting efficiency and the easier sample preparation, with no need for sample pre-concentration. In this work, liquid scintillation counting system was used to measure 222 Rn and 226 Ra levels in environmental samples. The liquid scintillation cocktail was prepared in the laboratory and was found efficient for measuring 222 Rn. Soil, sediment and TENORM samples were dried, grind, sieved and added to hydrochloric acid, in a standard scintillation vial, preloaded with the liquid scintillation cocktail. By measuring 222 Rn levels in the prepared vials, at different intervals of time after preparation, 222 Rn and 226 Ra levels were determined

A mass conserving level set method for detailed numerical simulation of liquid atomization

Energy Technology Data Exchange (ETDEWEB)

Luo, Kun; Shao, Changxiao [State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027 (China); Yang, Yue [State Key Laboratory of Turbulence and Complex Systems, Peking University, Beijing 100871 (China); Fan, Jianren, E-mail: fanjr@zju.edu.cn [State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027 (China)

2015-10-01

An improved mass conserving level set method for detailed numerical simulations of liquid atomization is developed to address the issue of mass loss in the existing level set method. This method introduces a mass remedy procedure based on the local curvature at the interface, and in principle, can ensure the absolute mass conservation of the liquid phase in the computational domain. Three benchmark cases, including Zalesak's disk, a drop deforming in a vortex field, and the binary drop head-on collision, are simulated to validate the present method, and the excellent agreement with exact solutions or experimental results is achieved. It is shown that the present method is able to capture the complex interface with second-order accuracy and negligible additional computational cost. The present method is then applied to study more complex flows, such as a drop impacting on a liquid film and the swirling liquid sheet atomization, which again, demonstrates the advantages of mass conservation and the capability to represent the interface accurately.

Actinide partitioning from high level liquid waste using the Diamex process

International Nuclear Information System (INIS)

Madic, C.; Blanc, P.; Condamines, N.; Baron, P.; Berthon, L.; Nicol, C.; Pozo, C.; Lecomte, M.; Philippe, M.; Masson, M.; Hequet, C.

1994-01-01

The removal of long-lived radionuclides, which belong to the so-called minor actinides elements, neptunium, americium and curium, from the high level nuclear wastes separated during the reprocessing of the irradiated nuclear fuels in order to transmute them into short-lived nuclides, can substantially decrease the potential hazards associated with the management of these nuclear wastes. In order to separate minor actinides from high-level liquid wastes (HLLW), a liquid-liquid extraction process was considered, based on the use of diamide molecules, which display the property of being totally burnable, thus they do not generate secondary solid wastes. The main extracting properties of dimethyldibutyltetradecylmalonamide (DMDBTDMA), the diamide selected for the development of the DIAMEX process, are briefly described in this paper. Hot tests of the DIAMEX process (using DMDBTDMA) related to the treatment of an mixed oxide fuels (MOX) type HLLW, were successfully performed. The minor actinide decontamination factors of the HLLW obtained were encouraging. The main results of these tests are presented and discussed in this paper. (authors). 9 refs., 2 figs., 7 tabs

The transport implications of regional policies for the disposal of intermediate level radioactive wastes

International Nuclear Information System (INIS)

James, I.A.

1985-09-01

This report aims to evaluate transport parameters and logistics associated with the disposal of intermediate-level radioactive wastes, as generated by CEGB, SSEB, UKAEA and BNFL. The assumed power scenario is DoE Scheme 3, which approximates to a moderate power generation scenario, with a 15 GWe PWR programme commissioned between 1991 and 2010, existing Magnox and AGR stations are assumed to have a 30 year lifespan. Three transport options are again assumed, namely; road, rail and a hybrid system, as is consistent with previous studies. These three options will be used in investigating regional policies of disposal, initially at the national level and then progressively disaggregating to a system of three regional depositories serving their respective catchment areas. (author)

Time depending assessment of low and intermediate radioactive waste characteristics from Cernavoda NPP

International Nuclear Information System (INIS)

Mateescu, S.; Pantazi, D.; Stanciu, M.

2002-01-01

Low and intermediate radioactive gaseous, liquid and solid waste produced at Cernavoda Nuclear Power Plant must be well known from the point of view of contained radionuclide activity, during all steps of their processing, storage and transport, to ensure the nuclear safety of radioactive waste management. As in intermediate storage stage, the waste activity changes by radioactive decay and nuclear transmutation, the evolution in time of these sources is necessary to be assessed, for the purpose of biological shielding determination at any time. On the other hand, during the transport of waste package at the repository, the external dose rates must meet the national and international requirements concerning radioactive materials transportation on public roads. In this paper, a calculation methodology for waste characterization based on external exposure rate measurement and on sample analysis results is presented. The time evolution of waste activity, as well as the corresponding shielding at different moments of management process, have been performed using MICROSHIELD-5 code. The spent resins proceeded from clean-up and purification systems and solutions from decontamination have been analyzed. The proposed methodology helps us to assess radiation protection during the handling of low and intermediate - level radioactive waste drums, ensuring safety conditions for the public and environment.(author)

Canadian experiences in characterizing two low-level and intermediate-level radioactive waste management sites

International Nuclear Information System (INIS)

Heystee, R.J.; Rao, P.K.M.

1984-02-01

Low-level waste (LLW) and intermediate-level reactor waste (ILW) arise in Canada from the operation of nuclear power reactors for the generation of electricity and from the operation of reactors for nuclear research and development as well as for the production of separated radioisotopes. The majority of this waste is currently being safely managed at two sites in the Province of Ontario: (1) Chalk River Nuclear Laboratories, and (2) Ontario Hydro's Bruce Nuclear Power Development Radioactive Waste Operations Site 2. Although these storage facilities can safely manage the waste for a long period of time, there are advantages in disposal of the LLW and ILW. The design of the disposal facilities and the assessment of long-term performance will require that the hydrologic and geologic data be gathered for a potential disposal site. Past site characterization programs at the two aforementioned waste storage sites have produced information which will be useful to future disposal studies in similar geologic materials. The assessment of long-term performance will require that predictions be made regarding the potential subsurface migration of radionuclides. However there still remain many uncertainties regarding the chemical and physical processes which affect radionuclide mobility and concentrations, in particular hydrodynamic dispersion, geochemical reactions, and transport through fractured media. These uncertainties have to be borne in mind when conducting the performance assessments and adequate conservatism must be included to account for the uncertainties. (author)

Separation of aromatic precipitates from simulated high level radioactive waste by hydrolysis, evaporation and liquid-liquid extraction

International Nuclear Information System (INIS)

Young, S.R.; Shah, H.B.; Carter, J.T.

1991-01-01

The Defense Waste Processing Facility (DWPF) at the SRS will be the United States' first facility to process High Level radioactive Waste (HLW) into a borosilicate glass matrix. The removal of aromatic precipitates by hydrolysis, evaporation and liquid-liquid extraction will be a key step in the processing of the HLW. This step, titled the Precipitate Hydrolysis Process, has been demonstrated by the Savannah River Laboratory with the Precipitate Hydrolysis Experimental Facility (PHEF). The mission of the PHEF is to demonstrate processing of simulated high level radioactive waste which contains tetraphenylborate precipitates and nitrite. Reduction of nitrite by hydroxylamine nitrate and hydrolysis of the tetraphenylborate by formic acid is discussed. Gaseous production, which is primarily benzene, nitrous oxide and carbon dioxide, has been quantified. Production of high-boiling organic compounds and the accumulation of these organic compounds within the process are addressed

Use of low density lipoprotein particle number levels as an aid in statin treatment decisions for intermediate risk patients: a cost-effectiveness analysis.

Science.gov (United States)

Shiffman, Dov; Arellano, Andre R; Caulfield, Michael P; Louie, Judy Z; Bare, Lance A; Devlin, James J; Melander, Olle

2016-12-07

The 2013 ACC/AHA guideline recommended either no statin therapy or moderate-intensity statin therapy (MST) for intermediate risk patients-those with 5-7.5% 10-year risk and without cardiovascular disease (CVD), hypercholesterolemia or diabetes. The guideline further suggested that the therapy choice be based on patient-clinician discussions of risks and benefits. Since low-density lipoprotein particle (LDL-P) levels were reported to be associated with CVD independently of traditional risk factors in intermediate and low risk patients, we investigated the cost-effectiveness of using LDL-P levels to identify intermediate risk patients likely to benefit from initiating or intensifying statin therapy. We evaluated 5 care strategies for intermediate risk patients. These included the strategies suggested by the guideline: no-statin therapy and MST. We compared each of these strategies to a related strategy that incorporated LDL-P testing. No-statin therapy was compared with the strategy of MST for those with high LDL-P levels and no statin therapy for all other patients (test-and-MST). MST was compared with the strategy of high-intensity statin therapy (HST) for those with high LDL-P levels and MST for all other patients (test-and-HST). We also evaluated the strategy of HST for all. Costs (payer perspective) and utilities were assessed over a 5-year time horizon in a Markov model of 100,000 hypothetical intermediate risk patients. HST dominated all other strategies, costing less and-despite causing 739 more cases of diabetes than did MST-resulting in more quality adjusted life-years (QALYs). For patient-clinician discussions that would otherwise lead to the MST strategy, we found the test-and-HST strategy reduced costs by $4.67 MM and resulted in 134 fewer CVD events and 115 additional QALYs. For patient-clinician discussions that would otherwise lead to no statin therapy, we found that the test-and-MST strategy reduced costs by $3.25 MM, resulted in 97 fewer CVD events

Investigation of students’ intermediate conceptual understanding levels: the case of direct current electricity concepts

International Nuclear Information System (INIS)

Aktan, D Cobanoglu

2013-01-01

Conceptual understanding is one of the main topics in science and physics education research. In the majority of conceptual understanding studies, students’ understanding levels were categorized dichotomously, either as alternative or scientific understanding. Although they are invaluable in many ways, namely developing new instructional materials and assessment instruments, students’ alternative understandings alone are not sufficient to describe students’ conceptual understanding in detail. This paper introduces an example of a study in which a method was developed to assess and describe students’ conceptual understanding beyond alternative and scientific understanding levels. In this study, six undergraduate students’ conceptual understanding levels of direct current electricity concepts were assessed and described in detail by using their answers to qualitative problems. In order to do this, conceptual understanding indicators are described based on science and mathematics education literature. The students’ understanding levels were analysed by assertion analysis based on the conceptual understanding indicators. The results indicated that the participants demonstrated three intermediate understanding levels in addition to alternative and scientific understanding. This paper presents the method and its application to direct current electricity concepts. (paper)

85,000-GPM, single-stage, single-suction LMFBR intermediate centrifugal pump

International Nuclear Information System (INIS)

Fair, C.E.; Cook, M.E.; Huber, K.A.; Rohde, R.

1983-01-01

The mechanical and hydraulic design features of the 85,000-gpm, single-stage, single-suction pump test article, which is designed to circulate liquid-sodium coolant in the intermediate heat-transport system of a Large-Scale Liquid Metal Fast Breeder Reactor (LS-LMFBR), are described. The design and analytical considerations used to satisfy the pump performance and operability requirements are presented. The validation of pump hydraulic performance using a hydraulic scale-model pump is discussed, as is the featute test for the mechanical-shaft seal system

Korean working towards low and intermediate level waste volume reduction

International Nuclear Information System (INIS)

Myung-Jae Song; Jong-Kil Park

2001-01-01

The safe management of radioactive waste is a national task required for sustainable generation of nuclear power and for energy self-reliance. This paper describes the results, efforts, and prospects for the safe management of radioactive wastes having been performed by the Nuclear Environment Technology Institute (NETEC) of the Korean Electric Power Corporation (KEPCO). Firstly, KEPCO's efforts and results for waste volume reduction are summarized to show how the number of waste drums generated per reactor-year could be reduced by about 60% during the last 10 years. Secondly, a new treatment technology, a technology for low and intermediate level waste (LILW) vitrification, was introduced to prospect how the technology reduces the waste volume and increases the inherent safety for LILW disposal. It is expected that the vitrification technology will contribute not only to reduce LILW volume to around 1/14 ∼ 1/32 but also to change the 'Not In My Back Yard' (NIMBY) syndrome to the 'Please In My Front Yard' (PIMFY) attitude of local communities/residents for LILW disposal. (author)

Simulation of Water Level Fluctuations in a Hydraulic System Using a Coupled Liquid-Gas Model

Directory of Open Access Journals (Sweden)

Chao Wang

2015-08-01

Full Text Available A model for simulating vertical water level fluctuations with coupled liquid and gas phases is presented. The Preissmann implicit scheme is used to linearize the governing equations for one-dimensional transient flow for both liquid and gas phases, and the linear system is solved using the chasing method. Some classical cases for single liquid and gas phase transients in pipelines and networks are studied to verify that the proposed methods are accurate and reliable. The implicit scheme is extended using a dynamic mesh to simulate the water level fluctuations in a U-tube and an open surge tank without consideration of the gas phase. Methods of coupling liquid and gas phases are presented and used for studying the transient process and interaction between the phases, for gas phase limited in a chamber and gas phase transported in a pipeline. In particular, two other simplified models, one neglecting the effect of the gas phase on the liquid phase and the other one coupling the liquid and gas phases asynchronously, are proposed. The numerical results indicate that the asynchronous model performs better, and are finally applied to a hydropower station with surge tanks and air shafts to simulate the water level fluctuations and air speed.

Predisposal Management of Low and Intermediate Level Radioactive Waste. Safety Guide

International Nuclear Information System (INIS)

2009-01-01

The objective of this Safety Guide is to provide regulatory bodies and the operators that generate and manage radioactive waste with recommendations on how to meet the principles and requirements established for the predisposal management of low and intermediate level waste. Contents: 1. Introduction; 2. Protection of human health and the environment; 3. Roles and responsibilities; 4. General safety considerations; 5. Safety features for the predisposal management of LILW; 6. Record keeping and reporting; 7. Safety assessment; 8. Quality assurance; Annex I: Nature and sources of LILW from nuclear facilities; Annex II: Development of specifications for waste packages; Annex III: Site conditions, processes and events for consideration in a safety assessment (external natural phenomena); Annex IV: Site conditions, processes and events for consideration in a safety assessment (external human induced phenomena); Annex V: Postulated initiating events for consideration in a safety assessment (internal phenomena).

Isoporphyrin intermediate in heme oxygenase catalysis. Oxidation of alpha-meso-phenylheme.

Science.gov (United States)

Evans, John P; Niemevz, Fernando; Buldain, Graciela; de Montellano, Paul Ortiz

2008-07-11

Human heme oxygenase-1 (hHO-1) catalyzes the O2- and NADPH-dependent oxidation of heme to biliverdin, CO, and free iron. The first step involves regiospecific insertion of an oxygen atom at the alpha-meso carbon by a ferric hydroperoxide and is predicted to proceed via an isoporphyrin pi-cation intermediate. Here we report spectroscopic detection of a transient intermediate during oxidation by hHO-1 of alpha-meso-phenylheme-IX, alpha-meso-(p-methylphenyl)-mesoheme-III, and alpha-meso-(p-trifluoromethylphenyl)-mesoheme-III. In agreement with previous experiments (Wang, J., Niemevz, F., Lad, L., Huang, L., Alvarez, D. E., Buldain, G., Poulos, T. L., and Ortiz de Montellano, P. R. (2004) J. Biol. Chem. 279, 42593-42604), only the alpha-biliverdin isomer is produced with concomitant formation of the corresponding benzoic acid. The transient intermediate observed in the NADPH-P450 reductase-catalyzed reaction accumulated when the reaction was supported by H2O2 and exhibited the absorption maxima at 435 and 930 nm characteristic of an isoporphyrin. Product analysis by reversed phase high performance liquid chromatography and liquid chromatography electrospray ionization mass spectrometry of the product generated with H2O2 identified it as an isoporphyrin that, on quenching, decayed to benzoylbiliverdin. In the presence of H218O2, one labeled oxygen atom was incorporated into these products. The hHO-1-isoporphyrin complexes were found to have half-lives of 1.7 and 2.4 h for the p-trifluoromethyl- and p-methyl-substituted phenylhemes, respectively. The addition of NADPH-P450 reductase to the H2O2-generated hHO-1-isoporphyrin complex produced alpha-biliverdin, confirming its role as a reaction intermediate. Identification of an isoporphyrin intermediate in the catalytic sequence of hHO-1, the first such intermediate observed in hemoprotein catalysis, completes our understanding of the critical first step of heme oxidation.

The MHD intermediate shock interaction with an intermediate wave: Are intermediate shocks physical?

International Nuclear Information System (INIS)

Wu, C.C.

1988-01-01

Contrary to the usual belief that MHD intermediate shocks are extraneous, the authors have recently shown by numerical solutions of dissipative MHD equations that intermediate shocks are admissible and can be formed through nonlinear steepening from a continuous wave. In this paper, he clarifies the differences between the conventional view and the results by studying the interaction of an MHD intermediate shock with an intermediate wave. The study reaffirms his results. In addition, the study shows that there exists a larger class of shocklike solutions in the time-dependent dissiaptive MHD equations than are given by the MHD Rankine-Hugoniot relations. it also suggests a mechanism for forming rotational discontinuities through the interaction of an intermediate shock with an intermediate wave. The results are of importance not only to the MHD shock theory but also to studies such as magnetic field reconnection models

Intensity liquid level sensor based on multimode interference and fiber Bragg grating

International Nuclear Information System (INIS)

Oliveira, Ricardo; Aristilde, Stenio; Osório, Jonas H; Cordeiro, Cristiano M B; Franco, Marcos A R; Bilro, Lúcia; Nogueira, Rogério N

2016-01-01

In this paper an intensity liquid level sensor based on a single-mode—no-core—single-mode (SMS) fiber structure together with a Bragg grating inscribed in the later single mode fiber is proposed. As the no-core fiber is sensitive to the external refractive index, the SMS spectral response will be shifted related to the length of no-core fiber that is immersed in a liquid. By positioning the FBG central wavelength at the spectral region of the SMS edge filter, it is possible to measure the liquid level using the reflected FBG peak power through an intensity-based approach. The sensor is also self-referenced using the peak power of another FBG that is placed before and far from the sensing part. The temperature error analysis was also studied revealing that the sensor can operate in environments where the temperature changes are minimal. The possibility to use a second setup that makes the whole device temperature insensitive is also discussed. (paper)

Reflections of Turkish accounting and financial reporting standards on vocational school students: A research on comparing perceptions of intermediate and mid-level accounting professional candidates

OpenAIRE

Seldüz Hakan; Seldüz Emine

2016-01-01

This research aims to compare the perceptions of intermediate and mid-level accounting professional candidates on accounting and financial reporting standards. A significant part of accounting process is carried out by vocational school graduate intermediate and mid-level accounting professionals. However, it can be claimed that adequate education about accounting and financial reporting standards isn’t given in vocational schools although these standards structure the whole accounting proces...

Low level liquid scintillation analysis for environmental and biomedical quantitation

International Nuclear Information System (INIS)

Kessler, M.J.

1991-01-01

Over the past five years low level liquid scintillation counting has become increasing popular because of the large number of applications which can be performed using this technique. These applications include environmental monitoring ( 3 H, 90 Sr/ 90 Y, etc.), radiocarbon dating (for age determination to 50,000 years), food adulteration studies (alcohol and beverage industries), radon monitoring (air/water), nuclear power plant monitoring (low level 3 H) and metabolism studies (pharmaceutical research). These applications can be performed with either a dedicated low level LSC or using a standard liquid scintillation counter in conjunction with the new technique of time-resolved LSC (TR-LSC). This technique when used on a standard LSC reduces the instrument background without substantially effecting the background, thus increasing the performance (E 2 /B) of the LSC. Data will be presented for each of the applications mentioned above, comparing the standard LSC and the new TR-LSC techniques. The optimization of the samples for each of these applications will be explored in detail with experimental results. In conclusion, by using the TR-LSC technique in conjunction with a standard LSC the performance of the standard LSC can be increased substantially without dedicating the LSC to doing only low level samples

The NA62 Liquid Krypton Electromagnetic Calorimeter Level 0 Trigger

CERN Document Server

INSPIRE-00293812; Paoluzzi, Giovanni; Salamon, Andrea; Salina, Gaetano; Santovetti, Emanuele; Scarfi, Francesco M.; Bonaiuto, Vincenzo; Sargeni, Fausto

2012-01-01

The NA62 experiment at CERN SPS aims to measure the Branching Ratio of the very rare kaon decay K+ -> pi+ nu nubar collecting O(100) events with a 10% background to make a stringent test of the Standard Model. One of the main backgrounds to the proposed measurement is represented by the K+ -> pi+ pi0 decay. To suppress this background an efficient photo veto system is foreseen. In the 1-10 mrad angular region the NA48 high performance liquid krypton electromagnetic calorimeter is used. The design, implementation and current status of the Liquid Krypton Electromagnetic Calorimeter Level 0 Trigger are presented.

The NA62 Liquid Krypton Electromagnetic Calorimeter Level 0 Trigger

CERN Document Server

INSPIRE-00646848; Fucci, Adolfo; Paoluzzi, Giovanni; Salamon, Andrea; Salina, Gaetano; Santovetti, Emanuele; Scarfi, Francesco M.; Sargeni, Fausto

2011-01-01

The NA62 experiment at CERN SPS aims to measure the Branching Ratio of the very rare kaon decay K+ -> pi+ nu nubar collecting O(100) events with a 10% background to make a stringent test of the Standard Model. One of the main backgrounds to the proposed measurement is represented by the K+ -> pi+ pi0 decay. To suppress this background an efficient photo veto system is foreseen. In the 1-10 mrad angular region the NA48 high performance liquid krypton electromagnetic calorimeter is used. The design, implementation and current status of the Liquid Krypton Electromagnetic Calorimeter Level 0 Trigger are presented.

Prestudy of final disposal of long-lived low and intermediate level waste

International Nuclear Information System (INIS)

Wiborgh, M.

1995-01-01

The repository for long-lived low and intermediate level waste, SFL 3-5, is foreseen to be located adjacent to the deep repository for spent encapsulated fuel, SFL 2. The SFL 3-5 repository comprises of three repository parts which will be used for the different categories of waste. In this report the work performed within a pre-study of the SFL 3-5 repository concept is summarised. The aim was to make a first preliminary and simplified assessment of the near-field as a barrier to radionuclide dispersion. A major task has been to compile information on the waste foreseen to be disposed of in SFL 3-5. The waste comprises of; low and intermediate level waste from Studsvik, operational waste from the central interim storage for spent fuel, CLAB, and the encapsulation plant, decommissioning waste from these facilities, and core components and internal parts from the reactors. The total waste volume has been estimated to about 25000 m 3 . The total activity content at repository closure is estimated to be about 1 ·10 17 Bq in SFL 3-5. At repository closure the short-lived radionuclides, for example Co-60 and Fe-55, have decayed considerably and the activity is dominated by nickel isotopes in the metallic waste from the reactors, to be disposed of in SFL 5. However, other radionuclides may be more or equally important from a safety point of view, e.g cesium-isotopes and actinides which are found in largest amounts in the SFL 3 waste. A first evaluation of the long term performance or the SFL 3-5 repository has been made. A systematic methodology for scenario formulation was tested. The near-field release of contaminants was calculated for a selected number of radionuclides and chemo-toxic elements. The radionuclide release calculations revealed that Cs-137 and Ni-63 would dominate the annual release from all repository parts during the first 1000 years after repository closure and that Ni-59 would dominate at longer times

Prestudy of final disposal of long-lived low and intermediate level waste

Energy Technology Data Exchange (ETDEWEB)

Wiborgh, M [ed.; Kemakta Konsult AB., Stockholm (Sweden)

1995-01-01

The repository for long-lived low and intermediate level waste, SFL 3-5, is foreseen to be located adjacent to the deep repository for spent encapsulated fuel, SFL 2. The SFL 3-5 repository comprises of three repository parts which will be used for the different categories of waste. In this report the work performed within a pre-study of the SFL 3-5 repository concept is summarised. The aim was to make a first preliminary and simplified assessment of the near-field as a barrier to radionuclide dispersion. A major task has been to compile information on the waste foreseen to be disposed of in SFL 3-5. The waste comprises of; low and intermediate level waste from Studsvik, operational waste from the central interim storage for spent fuel, CLAB, and the encapsulation plant, decommissioning waste from these facilities, and core components and internal parts from the reactors. The total waste volume has been estimated to about 25000 m{sup 3}. The total activity content at repository closure is estimated to be about 1 {center_dot}10{sup 17} Bq in SFL 3-5. At repository closure the short-lived radionuclides, for example Co-60 and Fe-55, have decayed considerably and the activity is dominated by nickel isotopes in the metallic waste from the reactors, to be disposed of in SFL 5. However, other radionuclides may be more or equally important from a safety point of view, e.g cesium-isotopes and actinides which are found in largest amounts in the SFL 3 waste. A first evaluation of the long term performance or the SFL 3-5 repository has been made. A systematic methodology for scenario formulation was tested. The near-field release of contaminants was calculated for a selected number of radionuclides and chemo-toxic elements. The radionuclide release calculations revealed that Cs-137 and Ni-63 would dominate the annual release from all repository parts during the first 1000 years after repository closure and that Ni-59 would dominate at longer times.

Derivation of intermediate to silicic magma from the basalt analyzed at the Vega 2 landing site, Venus.

Science.gov (United States)

Shellnutt, J Gregory

2018-01-01

Geochemical modeling using the basalt composition analyzed at the Vega 2 landing site indicates that intermediate to silicic liquids can be generated by fractional crystallization and equilibrium partial melting. Fractional crystallization modeling using variable pressures (0.01 GPa to 0.5 GPa) and relative oxidation states (FMQ 0 and FMQ -1) of either a wet (H2O = 0.5 wt%) or dry (H2O = 0 wt%) parental magma can yield silicic (SiO2 > 60 wt%) compositions that are similar to terrestrial ferroan rhyolite. Hydrous (H2O = 0.5 wt%) partial melting can yield intermediate (trachyandesite to andesite) to silicic (trachydacite) compositions at all pressures but requires relatively high temperatures (≥ 950°C) to generate the initial melt at intermediate to low pressure whereas at high pressure (0.5 GPa) the first melts will be generated at much lower temperatures (< 800°C). Anhydrous partial melt modeling yielded mafic (basaltic andesite) and alkaline compositions (trachybasalt) but the temperature required to produce the first liquid is very high (≥ 1130°C). Consequently, anhydrous partial melting is an unlikely process to generate derivative liquids. The modeling results indicate that, under certain conditions, the Vega 2 composition can generate silicic liquids that produce granitic and rhyolitic rocks. The implication is that silicic igneous rocks may form a small but important component of the northeast Aphrodite Terra.

Chemical conditions in the repository for low- and intermediate-level reactor waste

International Nuclear Information System (INIS)

Snellman, M.; Uotila, H.

1984-01-01

The chemical conditions in the proposed repositories for low- and intermediate-level reactor waste at Haestholmen (IVO) and Olkiluoto (TVO) have been discussed with respect to materials introduced into the repository, their possible long-term changes and interaction with groundwater flowing into the repository. The main possible groundwater-rock interactions have been discussed, as well as the role of micro-organisms, organic acids and colloids in the estimation of the barrier integrity. Experimental and theoretical studies have been performed on the basis of the natural groundwater compositions expected at the repository sites. Main emphasis is put on the chemical parameters which might influence the integrity of the different barriers in the repository as well as on the parameters which might effect the release and transport of radionuclides from the repository

OPG's deep geologic repository for low and intermediate level waste - recent progress

International Nuclear Information System (INIS)

King, F.K.

2006-01-01

This paper provides a status report on Canada's first project to build a permanent repository for the long-term management of radioactive waste. Ontario Power Generation has initiated a project to construct a deep geologic repository for low- and intermediate-level waste at the Bruce Nuclear Site, at a depth in the range of 600 to 800 m in an Ordovician-age argillaceous limestone formation. The project is currently undergoing an Environmental Assessment and consulting companies in the areas of environmental assessment, geoscientific site characterization, engineering and safety assessment have been hired and technical studies are underway. Seismic surveys and borehole drilling will be initiated in the fall of 2006. The next major milestone for the project is the submission of the Environmental Assessment report, currently scheduled for December 2008. (author)

The chemical, microbial, sensory and technological effects of intermediate salt levels as a sodium reduction strategy in fresh pork sausages.

Science.gov (United States)

Cluff, MacDonald; Steyn, Hannes; Charimba, George; Bothma, Carina; Hugo, Celia J; Hugo, Arno

2016-09-01

The reduction of sodium in processed meat products is synonymous with the use of salt replacers. Rarely has there been an assessment of the use of intermediate salt levels as a sodium reduction strategy in itself. In this study, 1 and 1.5% salt levels were compared with 0 and 2% controls in fresh pork sausages for effects on chemical, microbial, sensory and technological stability. Although significant (P sausages stored at 4 °C on days 6 and 9 and stored at -18 °C on days 90 and 180; taste, texture and overall liking during sensory evaluation; and % cooking loss, % total loss and % refrigeration loss. Consumers were able to differentiate between the 2 and 1% added NaCl treatments in terms of saltiness. This study indicated that salt reduction to intermediate levels can be considered a sodium reduction strategy in itself but that further research with regards to product safety is needed. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

A review of DOE chemical and geochemical research programmes (for disposal of low and intermediate level waste)

International Nuclear Information System (INIS)

May, R.

1987-01-01

A study of 26 DOE sponsored research programmes has been carried out with respect to their coverage of various chemical and geochemical issues posed by the proposed disposal of low and intermediate level wastes in a land repository. The study also took into account various experimental programmes sponsored by NIREX and abroad. The findings of the study are reported here. (author)

The influence of organic materials on the near field of an intermediate level waste radioactive waste repository

International Nuclear Information System (INIS)

Wilkins, J.D.

1988-02-01

The influence of organic materials, which are present in some intermediate level wastes, on the chemistry of the near field of a radioactive waste repository is discussed. Particular attention is given to the possible formation of water soluble complexing agents formed as a result of the radiation field and chemical conditions. The present state of the research is reviewed. (author)

Temporary core liquid level depression during cold-leg small-break LOCA effect of break size and power level

International Nuclear Information System (INIS)

Koizumi, Y.; Kumamaru, H.; Mimura, Y.; Kukita, Y.; Tasaka, K.

1989-01-01

Cold-leg small break LOCA experiments (0.5-10% break) were conducted at the large scale test facility (LSTF), a volumetrically-scaled (1/48) simulator of a PWR, of the ROSA-IV Program. When a break area was less than 2.5% of the scaled cold-leg flow area, the core liquid level was temporarily further depressed to the bottom elevation of the crossover leg during the loop seal clearing early in the transient only by the manometric pressure balance since no coolant remained in the upper portion of the primary system. When the break size was larger than 5%, the core liquid level was temporarily further depressed lower than the bottom elevation of the crossover leg during the loop seal clearing since coolant remained at the upper portion of the primary system; the steam generator (SG) U-tube upflow side and the SG inlet plenum, due to counter current flow limiting by updrafting steam while the coolant drained. The amount of coolant trapped there was dependent on the vapor velocity (core power); the larger the core power, the lower the minimum core liquid level. The RELAP5/MOD2 code reasonable predicted phenomena observed in the experiments. (orig./DG)

Management of radioactive liquid waste at the Idaho Chemical Processing Plant

International Nuclear Information System (INIS)

Bendixsen, C.L.

1992-01-01

Highly radioactive liquid wastes (HLLW) are routinely produced during spent nuclear fuel processing at the Idaho Chemical Processing Plant (ICPP), located at the Idaho National Engineering Laboratory (INEL). This paper discusses the processes and safe practices for management of the radioactive process waste streams, which processes include collection, concentration, interim storage, calcination to granular solids, and long-term intermediate storage. Over four million gallons of HLLW have been converted to a recoverable granular solid form through waste liquid injection into a high-temperature, fluidized bed wherein the wastes are converted to their respective solid oxides. The development of a glass ceramic solid for the long-term permanent disposal of the high level waste (HLW) solids is also described

High sensitivity optical fiber liquid level sensor based on a compact MMF-HCF-FBG structure

Science.gov (United States)

Zhang, Yunshan; Zhang, Weigang; Chen, Lei; Zhang, Yanxin; Wang, Song; Yan, Tieyi

2018-05-01

An ultra-high sensitivity fiber liquid level sensor based on wavelength demodulation is proposed and demonstrated. The sensor is composed of a segment of multimode fiber and a large aperture hollow-core fiber assisted by a fiber Bragg grating (FBG). Interference occurs due to core mismatching and different modes with different effective refractive indices. The experimental results show that the liquid level sensitivity of the sensor is 1.145 nm mm‑1, and the linearity is up to 0.996. The dynamic temperature compensation of the sensor can be achieved by cascading an FBG. Considering the high sensitivity and compact structure of the sensor, it can be used for real-time intelligent monitoring of tiny changes in liquid level.

Adolescents' Use of Basic, Intermediate, and Advanced Device Types for Vaping.

Science.gov (United States)

Pepper, Jessica K; MacMonegle, Anna J; Nonnemaker, James M

2017-12-23

Advanced models of electronic vaping products (EVPs) likely pose a greater risk to adolescent health than basic or intermediate models because advanced models deliver nicotine more effectively and heat e-liquid to higher temperatures, producing more harmful chemical emissions. However, little is known about adolescents' risk factors for using different device types. We used social media to recruit an online sample of 1,508 U.S. adolescents aged 15-17 who reported past 30-day use of e-cigarettes. We assessed tobacco use, beliefs and knowledge about EVPs, and EVP use behavior, including the device type participants use most frequently. We used multinomial logistic regression to examine differences between adolescents who usually use intermediate versus basic and advanced versus basic devices. Most respondents usually used modifiable advanced devices (56.8%) rather than basic "cigalike" (14.5%) or pen-style intermediate (28.7%) devices. Use of multiple device types was common, particularly among those who primarily used basic devices. Younger age and less frequent vaping were associated with mainly using basic devices. Adolescents who were older, male, personally bought their main device, and had ever mixed e-liquids were at elevated risk for usually using advanced devices. Adolescents who primarily use basic devices may be newer users who are experimenting with multiple devices. Future research should examine which adolescents are most likely to transition to advanced devices in order to develop targeted interventions. Regulators should consider strategies to reduce access to all types of EVPs, such as better enforcement of the current ban on sales to minors. This research addresses two gaps in research on adolescent electronic vaping product use: (1) characterizing use of advanced devices as distinct from intermediate devices rather than grouping them together and (2) examining factors associated with use of specific device types. This study suggests that there

Surface-type repository for low and intermediate level radioactive waste in the Republic of Croatia

International Nuclear Information System (INIS)

Kucar-Dragicevic, S.; Zarkovic, V.; Subasic, D.

1995-01-01

The low-level intermediate-level (LL/IL) radioactive waste repository siting and construction project is one of the activities related to establishing the rad waste management system in the Republic of Croatia. The repository project design is one in an array of project activities which also include the site selection procedure and public attitude issues. The prepared design documentation gives technical, safety and financial background relevant for making a final decision on the waste disposal type, and it includes the technological, mechanical, civil and financial documentation on the preliminary/basic design level. During the last few years, the preliminary design has been prepared and safety assessment conducted for the tunnel-type LL/IL rad waste repository. As the surface-type repository is one of alternatives for final disposal the design documentation for that repository type was prepared during 1994. (author)

Treatment of low-level liquid radioactive wastes by electrodialysis

International Nuclear Information System (INIS)

DelDebbio, J.A.; Donovan, R.I.

1986-01-01

This paper presents the results of pilot plant studies on the use of electrodialysis (ED) for the removal of radioactive and chemical contaminants from acidic low-level radioactive wastes resulting from nuclear fuel reprocessing operations. Decontamination efficiencies are reported for strontium-90, cesium-137, iodine-129, ruthenium-106 and mercury. Data for contaminant adsorption on ED membranes and liquid waste volumes generated are also presented

Methods for conversion of carbohydrates in ionic liquids to value-added chemicals

Science.gov (United States)

Zhao, Haibo [The Woodlands, TX; Holladay, Johnathan E [Kennewick, WA; Zhang, Zongchao C [Norwood, NJ

2011-05-10

Methods are described for converting carbohydrates including, e.g., monosaccharides, disaccharides, and polysaccharides in ionic liquids to value-added chemicals including furans, useful as chemical intermediates and/or feedstocks. Fructose is converted to 5-hydroxylmethylfurfural (HMF) in the presence of metal halide and acid catalysts. Glucose is effectively converted to HMF in the presence of chromium chloride catalysts. Yields of up to about 70% are achieved with low levels of impurities such as levulinic acid.

Radiochemical methodologies applied to analytical characterization of low and intermediate level wastes from nuclear power plants

International Nuclear Information System (INIS)

Monteiro, Roberto Pellacani G.; Júnior, Aluísio Souza R.; Kastner, Geraldo F.; Temba, Eliane S.C.; Oliveira, Thiago C. de; Amaral, Ângela M.; Franco, Milton B.

2017-01-01

The aim of this work is to present radiochemical methodologies developed at CDTN/CNEN in order to answer a program for isotopic inventory of radioactive wastes from Brazilian Nuclear Power Plants. In this program some radionuclides, 3 H, 14 C, 55 Fe, 59 Ni, 63 Ni, 90 Sr, 93 Zr, 94 Nb, 99 Tc, 129 I, 235 U, 238 U, 238 Pu, 239 + 240 Pu, 241 Pu, 242 Pu, 241 Am, 242 Cm e 243 + 244 Cm, were determined in Low Level Wastes (LLW) and Intermediate Level Wastes (ILW) and a protocol of analytical methodologies based on radiochemical separation steps and spectrometric and nuclear techniques was established. (author)

Liquid low level waste management expert system

International Nuclear Information System (INIS)

Ferrada, J.J.; Abraham, T.J.; Jackson, J.R.

1991-01-01

An expert system has been developed as part of a new initiative for the Oak Ridge National Laboratory (ORNL) systems analysis program. This expert system will aid in prioritizing radioactive waste streams for treatment and disposal by evaluating the severity and treatability of the problem, as well as the final waste form. The objectives of the expert system development included: (1) collecting information on process treatment technologies for liquid low-level waste (LLLW) that can be incorporated in the knowledge base of the expert system, and (2) producing a prototype that suggests processes and disposal technologies for the ORNL LLLW system. 4 refs., 9 figs

Expert system for liquid low-level waste management

International Nuclear Information System (INIS)

Ferrada, J.J.

1992-01-01

An expert system prototype has been developed to support system analysis activities at the Oak Ridge National Laboratory (ORNL) for waste management tasks. This expert system will aid in prioritizing radioactive waste streams for treatment and disposal by evaluating the severity and treatability of the problem as well as the final waste form. The objectives of the expert system development included: (1) collecting information on process treatment technologies for liquid low-level waste (LLLW) that can be incorporated in the knowledge base of the expert system, and (2) producing a prototype that suggests processes and disposal technologies for the ORNL LLLW system. The concept under which the expert system has been designed is integration of knowledge. There are many sources of knowledge (data bases, text files, simulation programs, etc.) that an expert would regularly consult in order to solve a problem of liquid waste management. The expert would normally know how to extract the information from these different sources of knowledge. The general scope of this project would be to include as much pertinent information as possible within the boundaries of the expert system. As a result, the user, who may not be an expert in every aspect of liquid waste management, may be able to apply the content of the information to a specific waste problem. This paper gives the methodological steps to develop the expert system under this general framework

Altered dopamine levels induced by the parasite Profilicollis antarcticus on its intermediate host, the crab Hemigrapsus crenulatus

Directory of Open Access Journals (Sweden)

JOSÉ MIGUEL ROJAS

2005-01-01

Full Text Available A serotonergic pathway is apparently involved in parasite-host interactions. Previous studies conducted in our laboratory showed increased rates in oxygen consumption and alterations in body posture in the crab Hemigrapsus crenulatus parasitized by the acanthocephalan, Profilicollis antarcticus. Such changes may be related to the functions described for biogenic amines in crustaceans. During the infective stage the acanthocephalans live freely in the hemocelomic cavity, suggesting that the possible alteration induced by biogenic amines may be related to their neurohormonal function in crustaceans. To test whether the presence of P. antarcticus produced neurohormonal changes in its intermediate host, H. crenulatus, we analyzed serotonin and dopamine levels in the host using HPLC with electrochemical detection. Two groups of 11 female crabs were studied; one group was artificially inoculated with two cystacanths while the other was used as the control. Our results show a dramatic increase in hemolymph dopamine, but not serotonin in H. crenulatus parasitized by the acanthocephalan P. antarcticus. Our results, along with those reported by Maynard (1996, suggest a parasite-specific strategy involved in the behavior alteration caused by the acanthocephalans on their intermediate host. The use of a biogenic amine as a mechanism of interaction by the parasites gives them an endless number of alternative potential actions on their intermediate hosts

Altered dopamine levels induced by the parasite Profilicollis antarcticus on its intermediate host, the crab Hemigrapsus crenulatus.

Science.gov (United States)

Rojas, José Miguel; Ojeda, F Patricio

2005-01-01

A serotonergic pathway is apparently involved in parasite-host interactions. Previous studies conducted in our laboratory showed increased rates in oxygen consumption and alterations in body posture in the crab Hemigrapsus crenulatus parasitized by the acanthocephalan, Profilicollis antarcticus. Such changes may be related to the functions described for biogenic amines in crustaceans. During the infective stage the acanthocephalans live freely in the hemocelomic cavity, suggesting that the possible alteration induced by biogenic amines may be related to their neurohormonal function in crustaceans. To test whether the presence of P. antarcticus produced neurohormonal changes in its intermediate host, H. crenulatus, we analyzed serotonin and dopamine levels in the host using HPLC with electrochemical detection. Two groups of 11 female crabs were studied; one group was artificially inoculated with two cystacanths while the other was used as the control. Our results show a dramatic increase in hemolymph dopamine, but not serotonin in H. crenulatus parasitized by the acanthocephalan P. antarcticus. Our results, along with those reported by Maynard (1996), suggest a parasite-specific strategy involved in the behavior alteration caused by the acanthocephalans on their intermediate host. The use of a biogenic amine as a mechanism of interaction by the parasites gives them an endless number of alternative potential actions on their intermediate hosts.

A methodology for assessing social considerations in transport of low and intermediate level radioactive waste

International Nuclear Information System (INIS)

Allsop, R.E.; Banister, D.J.; Holden, D.J.; Bird, J.; Downe, H.E.

1986-05-01

A methodology is proposed for taking into account non-radiological social aspects of the transport of low and intermediate level radioactive waste when considering the location of disposal facilities and the transport of waste to such facilities from the sites where it arises. As part of a data acquisition programme, an attitudinal survey of a sample of people unconnected with any suggested site or transport route is proposed in order to estimate levels of concern felt by people of different kinds about waste transport. Probabilities of accident occurrence during transport by road and rail are also discussed, and the limited extent of quantified information about consequences of accidents is reviewed. The scope for malicious interference with consignments of waste in transit is considered. (author)

Handling and storage of high-level liquid wastes from reprocessing of spent fuel

International Nuclear Information System (INIS)

Finsterwalder, L.

1982-01-01

The high level liquid wastes arise from the reprocessing of irradiated nuclear fuels, which are dissolved in aqueous acid solution, and the plutonium and unburned uranium removed in the chemical separation plant. The remaining solution, containing more than 99% of the dissolved fission products, together with impurities from cladding materials, corrosion products, traces of unseparated plutonium and uranium and most of the transuranic elements, constitutes the high-level waste. At present, these liquid wastes are usually concentrated by evaporation and stored as an aqueous nitric acid solution in high-integrity stainless-steel tanks. There is now world-wide agreement that, for the long term, these liquid wastes should be converted to solid form and much work is in progress to develop techniques for the solidification of these wastes. This paper considers the design requirements for such facilities and the experience gained during nearly 30 years of operation. (orig./RW)

Improved cement solidification of low and intermediate level radioactive wastes

International Nuclear Information System (INIS)

1993-01-01

Cementation was the first and is still the most widely applied technique for the conditioning of low and intermediate level radioactive wastes. Compared with other solidification techniques, cementation is relatively simple and inexpensive. However, the quality of the final cemented waste forms depends very much on the composition of the waste and the type of cement used. Different kinds of cement are used for different kinds of waste and the compatibility of a specific waste with a specific cement type should always be carefully evaluated. Cementation technology is continuously being developed in order to improve the characteristics of cemented waste in accordance with the increasing requirements for quality of the final solidified waste. Various kinds of additives and chemicals are used to improve the cemented waste forms in order to meet all safety requirements. This report is meant mainly for engineers and designers, to provide an explanation of the chemistry of cementation systems and to facilitate the choice of solidification agents and processing equipment. It reviews recent developments in cementation technology for improving the quality of cemented waste forms and provides a brief description of the various cement solidification processes in use. Refs, figs and tabs

Resistance of Feather-Associated Bacteria to Intermediate Levels of Ionizing Radiation near Chernobyl.

Science.gov (United States)

Ruiz-González, Mario Xavier; Czirják, Gábor Árpád; Genevaux, Pierre; Møller, Anders Pape; Mousseau, Timothy Alexander; Heeb, Philipp

2016-03-15

Ionizing radiation has been shown to produce negative effects on organisms, although little is known about its ecological and evolutionary effects. As a study model, we isolated bacteria associated with feathers from barn swallows Hirundo rustica from three study areas around Chernobyl differing in background ionizing radiation levels and one control study site in Denmark. Each bacterial community was exposed to four different γ radiation doses ranging from 0.46 to 3.96 kGy to test whether chronic exposure to radiation had selected for resistant bacterial strains. Experimental radiation duration had an increasingly overall negative effect on the survival of all bacterial communities. After exposure to γ radiation, bacteria isolated from the site with intermediate background radiation levels survived better and produced more colonies than the bacterial communities from other study sites with higher or lower background radiation levels. Long-term effects of radiation in natural populations might be an important selective pressure on traits of bacteria that facilitate survival in certain environments. Our findings indicate the importance of further studies to understand the proximate mechanisms acting to buffer the negative effects of ionizing radiation in natural populations.

Gasoline Engine Mechanics. Performance Objectives. Intermediate Course.

Science.gov (United States)

Jones, Marion

Several intermediate performance objectives and corresponding criterion measures are listed for each of six terminal objectives presented in this curriculum guide for an intermediate gasoline engine mechanics course at the secondary level. (For the beginning course guide see CE 010 947.) The materials were developed for a two-semester (2 hour…

Solvency and Liquidity Level Trade-off: Does it Exist in Croatian Banking Sector?

Directory of Open Access Journals (Sweden)

Kundid Novokmet Ana

2016-11-01

Full Text Available We focus on 32 Croatian banks in the period 2002-2010 in order to investigate the solvency-liquidity nexus. Dynamic panel data analysis is applied on two basic models in which current liquidity ratio and equity to assets ratio are set as dependent variables, interchangeably, and other explanatory variables employed to capture the effect of bank size, profitability and asset quality as well as macroeconomic environment. We found two-way positive relationship between bank solvency and liquidity. However, bank size plays an important role in the capital and liquidity management, and trade-off between the solvency and liquidity level is found for the larger banks. Therefore, policymakers should take into consideration capital and liquidity interdependence, as well as the bank size effect when designing capital and liquidity requirements in order to downsize the regulatory burden for smaller banks, and increase them for larger banks. Namely, larger banks tend to minimize regulatory costs by avoiding simultaneous increase of liquidity and solvency. Small banks do exactly the opposite and stock both, capital and liquidity, what potentially makes their funds allocation sub-optimal, from their own as well as social point of view. Altogether, the paper contributes to scarce empirical evidence regarding bank solvency and liquidity interdependence, particularly when the post-transitional banking sectors are taken into consideration. It adds to knowledge on bank financial management in praxis, and bank managers and prudential authorities might find it relevant for their policies design and implementation.

Has Banks’ Financial Intermediation Improved in Russia?

OpenAIRE

Fungachova, Z.; Solanko, L.

2010-01-01

The aim of this paper is to analyze the increasing importance of banks in the Russian economy over the period following the financial crisis of 1998. We use several measures to assess the role of banks in domestic financial intermediation in Russia. The traditional macro-level view is complemented by the analysis of sectoral financial flows as well as by insights from micro-level studies. All of these confirm that banks are becoming increasingly important in financial intermediation. We find ...

Cross flow filtration of Oak Ridge National Laboratory liquid low-level waste

International Nuclear Information System (INIS)

Fowler, V.L.; Hewitt, J.D.

1989-12-01

A new method for disposal of Oak Ridge National Laboratory liquid low-level radioactive waste is being developed as an alternative to hydrofracture. The acceptability of the final waste form rests in part on the presence or absence of transuranic (TRU) isotopes. Inertial cross flow filtration was used in this study to determine the potential of this method for separation of the TRU isotopes from the bulk liquid stored in the Melton Valley Storage Tanks. 7 refs., 11 figs., 5 tabs

A study on the establishment of the regulatory guide to the characteristics and classification criteria of low and intermediate level radioactive waste

Energy Technology Data Exchange (ETDEWEB)

Lee, Geon Jae; Paek, Min Hoon; Park, Jong Gil; Han, Byeong Seop; Cheong, Jae Hak; Lee, Hae Chan; Yang, Jin Yeong; Hong, Hei Kwan; Park, Jin Baek [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

1995-01-15

The objectives of this study are the development of regulatory guidance to the establishment of the necessary technology standard of the characteristics and classification criteria of low and intermediate level radioactive waste for the safe operation of the waste repositories. In followings, the contents of our report will be presented in two parts. Survey of the characteristics of radioactive waste : investigate and analyze the source, types and characteristics of domestic radioactive waste as a basis for this study, radiochemical analysis of radioactive waste based on foreign and domestic data base, determination of the methodology for the application of the characteristic analysis of waste classification technology. Establishment of the classification criteria of the radioactive waste : collection and analysis of foreign and domestic data base on the classification methodology and criteria, development of low and intermediate level waste classification criteria and the set up of the classification methodology through the analysis of waste data, establishment of the systematic classification methodology of the low and intermediate radioactive waste through the careful survey of the current domestic regulation.

Measurement of liquid level in a natural circulation circuit using an ultrasonic technique

International Nuclear Information System (INIS)

Barbosa, Amanda Cardozo; Su, Jian

2017-01-01

The measurement by an ultrasonic technique of the water level in the expansion tank of the Natural Circulation Circuit (NCC) of the Experimental Thermo-Hydraulic Laboratory of the Institute of Nuclear Engineering is presented. In the single-phase NCC operation the water level in the expansion tank is stable. However, during the two-phase operation, oscillations occur in the water level due to temperature and vacuum fraction variations. Thus, the development of a technique that allows the measurement of these oscillations, will allow an estimation of the variation of the vacuum fraction of the circuit over time. The experimental set - up was performed on a test bench, using an ultrasonic transducer. The ultrasonic technique used is pulse-echo, in which the same transducer is the transmitter and receiver of the signal. The transducer-shoe assembly is part of an ultrasonic system consisting of an ultrasonic signal generating plate, transducers and a computer (PC) with a program in LabView to control the system. The program is able to calculate the transit time that the ultrasonic signals take to cross the tank base wall, the layer (level) of liquid and return to the transducer. Knowing the speed of the ultrasound in the wall and in the liquid it is possible to calculate the thickness of the wall and the height of the liquid. Measurements were made by filling the tank with a known volume of water and under varying temperature conditions, from room temperature to 90 deg C. The liquid heights are determined and the volume of water calculated by measuring the temperature with a digital thermometer. The volumes measured were highly accurate when compared to the known volumes

Autothermal Processing of Renewable Liquids

Science.gov (United States)

Kruger, Jacob Scott

The vast majority of petrochemicals are synthesized from just six building block molecules, but current feedstocks are an unsustainable resource with negative externalities. Biomass represents a potentially sustainable feedstock, but needs densification, preferably to a liquid form, to be a suitable replacement. Fermentation to butanol and pyrolysis to bio-oil are two promising liquid intermediates. Catalytic partial oxidation (CPO) of the liquid intermediates over noble metal catalysts, which converts the liquids primarily into syngas and light olefins, is a promising technique for processing densified biomass. The study of liquids at high temperatures requires consideration of a range of complex phenomena, including boiling behavior on hot surfaces, reactions of the feed molecules at high temperatures and on catalyst surfaces, and interactions of impurities in the liquid with the catalyst. Chapter 2 deals with the behavior of the transient liquid that forms when cellulose, a major constituent of biomass, is pyrolized. Fast photography experiments and numerical simulations are performed to show that the aerosols formed in the boiling of this liquid are capable of transporting nonvolatile fragments of biomass intact into the gas phase. These nonvolatile fragments have significant implications in the storage and downstream processing of bio-oil. Some of the behavior of bio-oil at high temperature may also be explained by the variety of molecules in the liquid. Many different functional groups are present, each with its own set of chemical reactions in combustion, pyrolysis, and partial oxidation on a metal catalyst. Chapters 3 and 4 investigate these reactions through a survey of two-carbon surrogates of the functional group classes found in bio-oil. Chapter 3 examines reactions occuring in the complete CPO system over Pt and Rh catalysts, and in the complete system absent O 2. The selectivity data from each molecule and the surface science literature of each

Flow proportional sampling of low level liquid effluent

International Nuclear Information System (INIS)

Colley, D.; Jenkins, R.

1989-01-01

A flow proportional sampler for use on low level radioactive liquid effluent has been developed for installation on all CEGB nuclear power stations. The sampler, operates by drawing effluent continuously from the main effluent pipeline, through a sampler loop and returning it to the pipeline. The effluent in this loop is sampled by taking small, frequent aliquots using a linear acting shuttle valve. The frequency of operation of this valve is controlled by a flowmeter installed in the effluent line; sampling rate being directly proportional to effluent flowrate. (author)

Functions and requirements document, WESF decoupling project, low-level liquid waste system

Energy Technology Data Exchange (ETDEWEB)

Rasmussen, J.H., Fluor Daniel Hanford

1997-02-27

The Waste Encapsulation and Storage Facility (WESF) was constructed in 1974 to encapsulate and store cesium and strontium which were isolated at B Plant from underground storage tank waste. The WESF, Building 225-B, is attached physically to the west end of B Plant, Building 221-B, 200 East area. The WESF currently utilizes B Plant facilities for disposing liquid and solid waste streams. With the deactivation of B Plant, the WESF Decoupling Project will provide replacement systems allowing WESF to continue operations independently from B Plant. Four major systems have been identified to be replaced by the WESF Decoupling Project, including the following: Low Level Liquid Waste System, Solid Waste Handling System, Liquid Effluent Control System, and Deionized Water System.

Fiber optic liquid-level sensor using a long fiber Bragg grating

Science.gov (United States)

Ricchiuti, Amelia L.; Barrera, David; Nonaka, Koji; Sales, Salvador

2013-05-01

A technique for liquid-level sensors based on a long fiber Bragg grating (FBG) is presented and experimentally demonstrated. The measurement system is based on the measurement of the central frequency distribution of the FBG based on time-frequency domain analysis. A short optical pulse is injected into a 10-cm long FBG mounted in a container. The back-reflected pulse is scanned by means of an oscilloscope. When part of the grating is immersed in a liquid having temperature higher than the surrounding ambient, the structure of the uniform grating is distorted and its time-frequency response changes. A spatial resolution of 2 mm, given by the input pulse duration, and a 10-cm long measurement range are achieved. Liquid-temperature sensing has also been implemented by scanning the spectral response of the FBG by means of a CW laser and an OSA.

Concept development of exchange liquid regeneration

International Nuclear Information System (INIS)

Mader, D.L.

1985-08-01

Concepts are described for regeneration of the intermediate liquid used for isotope exchange in indirect laser isotope separation processes where the laser operates on a process gas distinct from the feed stream. The specific case of regeneration of an exchange liquid consisting of water, sodium hydroxide, and dimethyl sulfoxide for a process to separate deuterium from hydrogen using laser irradiation of trifluoromethane gas is developed. A water feed stream is converted to steam which rises in a chemical process column where it redeuterates a descending flow of exchange liquid without causing significant changes in its chemical composition

Intermediate, low, and very low level waste management at ANDRA (agence nationale pour la gestion des dechets radioactifs) in France

International Nuclear Information System (INIS)

Senoo, Muneaki

2005-01-01

On 28th September in 2004, RANDEC invited Mr. Jean-Louis Tison from ANDRA as a lecturer of the special session of the 16th RANDEC Annual Symposium. An ANDRA-RANDEC technical meeting was held on the next day, where Mr. Vincent Carlier invited from ANDRA, too participated. Here, present status of intermediate, low, and very low level waste management in France is reviewed based on the information which were obtained from the special session of the 16th RANDEC Annual Symposium and the ANDRA-RANDEC technical meeting. In France, ANDRA is implementing radioactive waste management under the following policy; 'Intermediate, low, and very-low-level (ILVLL) waste is managed in order to establish as soon as possible a final disposal system, the temporary or long term storage option being considered only for the high-level waste (HLW) such as the vitrified fission products or particular materials such as some sealed sources for which no final disposal solution still exists.' The Agency is financed on the basis of the 'polluter-pays' principle and contracts its services directly with waste owners. (author)

An assessment of filter aids and filter cloths in the dewatering of intermediate level wastes

International Nuclear Information System (INIS)

Knibbs, R.H.; Hudson, B.C.; Blackwell, J.C.W.

1984-12-01

This report considers a range of filter cloths and precoat materials intended for use in dewatering intermediate level radioactive wastes, and their interaction when used on a rotary drum vacuum filter. The report outlines the advantages and disadvantages of various grades and types of precoat and shows that grades with permeabilities in the intermediate range, 3 to 4 x 10 -12 m 2 , give satisfactory filtrate quality together with ease of operation. The work on filter cloths shows that: radiation damage is not a limiting factor as regards operational life for any of the cloths examined; polyester-based cloths are unsuitable due to their poor resistance to alkali attack; polyamide cloths are satisfactory; and stainless steel Dutch weave cloths are satisfactory and have the added advantage of high strength. The report also briefly considers the radiation resistance of two elastomeric membranes used on the 'epidermal' filter and shows that the natural latex rubber membrane is considerably more resistant to radiation than the silicone rubber membrane and has an estimated operational life of at least 1200 hours when dewatering Magnox silo sludge or α-contaminated alumino ferric flocs. (author)

A Western Blot-based Investigation of the Yeast Secretory Pathway Designed for an Intermediate-Level Undergraduate Cell Biology Laboratory

Science.gov (United States)

Hood-DeGrenier, Jennifer K.

2008-01-01

The movement of newly synthesized proteins through the endomembrane system of eukaryotic cells, often referred to generally as the secretory pathway, is a topic covered in most intermediate-level undergraduate cell biology courses. An article previously published in this journal described a laboratory exercise in which yeast mutants defective in…

Treatment and conditioning of metallic intermediate level waste

International Nuclear Information System (INIS)

Lidar, Per; Larsson, Arne; Huutoniemi, Tommi; Blank, Eva; Elfwing, Mattias

2014-01-01

In 2011 SKB started an R and D program for evaluating different disposal concepts for LL-LILW. The purpose was to develop alternative repository concepts and conditioning methods for LL-LILW and to evaluate and compare them from a range of parameters. The goal is to present a comparison between identified repository concepts by 2013. The material should be of such a quality that SKB can make decisions of which concepts that are to be further investigated in a safety analysis. As a part of the R and D program for the LL-LILW disposal facility, Studsvik was assigned to investigate whether melting of metallic LL-LILW is technically feasible and, if so, what the requirements are to build and operate such a facility. Specific concern was given to the following metallic components: - Core components and reactor internals from both boiling water reactors (BWRs) and pressurized water reactors (PWRs). - Reactor pressure vessels from PWRs. The paper presents a feasibility study of a melting facility for core components and reactor internals. An overview is given of how such a facility for treatment of intermediate level waste might be designed, constructed and operated and highlights both the possibilities and challenges. A cost estimate and a risk analysis are presented in order to make a conclusion of the technical feasibility of such a facility. Based on the Studsvik authors' experience in operating a low level waste melting facility, their conclusion is presented in the paper, considering cost of constructing and operating such a facility, in conjunction with the radio-logical risks associated with operation and the benefits to disposal and long term safety. Studsvik also investigated alternative techniques for embedding of metallic ILW components. Embedding of radioactive metallic ILW components protects the component from corrosion and leakage of radionuclides from repository to biosphere can thereby be both delayed and decreased. Conditioning by embedding has

Radioactive Operations Committee Review of the Intermediate-Level Waste Evaporator Facility, Building 2531 February 17, 1972

International Nuclear Information System (INIS)

Liberman, B.; Brooksbank, R.E.

1972-01-01

A subcommittee of the Radioactive Operations Committee met with the Operators of the Intermediate Level Waste Evaporator Facility on February 17, 1972, to discuss the status of the facility and its operations since the review of October 7, 1970, and reported in ORNL-CF-70-11-12. This review was made to determine the status of the ILWEF since the last review, to discuss compliance with previously recommended changes, and to review any new items of safety significance. Several recommendations were made.

Current construction status of Korea Wolsong Nuclear Environment Management Center (low and intermediate level radioactive waste disposal facility)

International Nuclear Information System (INIS)

Suzuki, Yasuo

2010-01-01

Through the RANDEC delegation tour to Korea in Nov. 2009, we have earned new information on recent development of the radioactive waste management in Korea. In this report, we will introduce such development in Korea, focusing on the current construction status of Korean LILW (low and intermediate level radioactive waste) disposal site, now called, Wolsong Nuclear Environment Management Center. (author)

Stabilization of liquid low-level and mixed wastes: a treatability study

International Nuclear Information System (INIS)

Carson, S.; Cheng, Yu-Cheng; Yellowhorse, L.; Peterson, P.

1996-01-01

A treatability study has been conducted on liquid low-level and mixed wastes using the stabilization agents Aquaset, Aquaset II, Aquaset II-H, Petroset, Petroset-H, and Petroset and Petroset II. A total of 40 different waste types with activities ranging from 10 -14 to 10 -4 curies/ml have been stabilized. Reported data for each waste include its chemical and radiological composition and the optimum composition or range of compositions (weight of agent/volume of waste) for each stabilization agent used. All wastes were successfully stabilized with one or more of the stabilization agents and all final waste forms passed the Paint Filter Liquids Test (EPA Method 9095)

Comparison of three-phase three-level voltage source inverter with intermediate dc–dc boost converter and quasi-Z-source inverter

DEFF Research Database (Denmark)

Panfilov, Dmitry; Husev, Oleksandr; Blaabjerg, Frede

2016-01-01

This study compares a three-phase three-level voltage source inverter with an intermediate dc-dc boost converter and a quasi-Z-source inverter in terms of passive elements values and dimensions, semiconductor stresses, and overall efficiency. A comparative analysis was conducted with relative...

Landau Levels of Majorana Fermions in a Spin Liquid.

Science.gov (United States)

Rachel, Stephan; Fritz, Lars; Vojta, Matthias

2016-04-22

Majorana fermions, originally proposed as elementary particles acting as their own antiparticles, can be realized in condensed-matter systems as emergent quasiparticles, a situation often accompanied by topological order. Here we propose a physical system which realizes Landau levels-highly degenerate single-particle states usually resulting from an orbital magnetic field acting on charged particles-for Majorana fermions. This is achieved in a variant of a quantum spin system due to Kitaev which is distorted by triaxial strain. This strained Kitaev model displays a spin-liquid phase with charge-neutral Majorana-fermion excitations whose spectrum corresponds to that of Landau levels, here arising from a tailored pseudomagnetic field. We show that measuring the dynamic spin susceptibility reveals the Landau-level structure by a remarkable mechanism of probe-induced bound-state formation.

Liquid identification by Hilbert spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Lyatti, M; Divin, Y; Poppe, U; Urban, K, E-mail: M.Lyatti@fz-juelich.d, E-mail: Y.Divin@fz-juelich.d [Forschungszentrum Juelich, 52425 Juelich (Germany)

2009-11-15

Fast and reliable identification of liquids is of great importance in, for example, security, biology and the beverage industry. An unambiguous identification of liquids can be made by electromagnetic measurements of their dielectric functions in the frequency range of their main dispersions, but this frequency range, from a few GHz to a few THz, is not covered by any conventional spectroscopy. We have developed a concept of liquid identification based on our new Hilbert spectroscopy and high- T{sub c} Josephson junctions, which can operate at the intermediate range from microwaves to THz frequencies. A demonstration setup has been developed consisting of a polychromatic radiation source and a compact Hilbert spectrometer integrated in a Stirling cryocooler. Reflection polychromatic spectra of various bottled liquids have been measured at the spectral range of 15-300 GHz with total scanning time down to 0.2 s and identification of liquids has been demonstrated.

Liquid identification by Hilbert spectroscopy

Science.gov (United States)

Lyatti, M.; Divin, Y.; Poppe, U.; Urban, K.

2009-11-01

Fast and reliable identification of liquids is of great importance in, for example, security, biology and the beverage industry. An unambiguous identification of liquids can be made by electromagnetic measurements of their dielectric functions in the frequency range of their main dispersions, but this frequency range, from a few GHz to a few THz, is not covered by any conventional spectroscopy. We have developed a concept of liquid identification based on our new Hilbert spectroscopy and high- Tc Josephson junctions, which can operate at the intermediate range from microwaves to THz frequencies. A demonstration setup has been developed consisting of a polychromatic radiation source and a compact Hilbert spectrometer integrated in a Stirling cryocooler. Reflection polychromatic spectra of various bottled liquids have been measured at the spectral range of 15-300 GHz with total scanning time down to 0.2 s and identification of liquids has been demonstrated.

Liquid identification by Hilbert spectroscopy

International Nuclear Information System (INIS)

Lyatti, M; Divin, Y; Poppe, U; Urban, K

2009-01-01

Fast and reliable identification of liquids is of great importance in, for example, security, biology and the beverage industry. An unambiguous identification of liquids can be made by electromagnetic measurements of their dielectric functions in the frequency range of their main dispersions, but this frequency range, from a few GHz to a few THz, is not covered by any conventional spectroscopy. We have developed a concept of liquid identification based on our new Hilbert spectroscopy and high- T c Josephson junctions, which can operate at the intermediate range from microwaves to THz frequencies. A demonstration setup has been developed consisting of a polychromatic radiation source and a compact Hilbert spectrometer integrated in a Stirling cryocooler. Reflection polychromatic spectra of various bottled liquids have been measured at the spectral range of 15-300 GHz with total scanning time down to 0.2 s and identification of liquids has been demonstrated.

Level trend analysis summary report for Oak Ridge National Laboratory inactive liquid low-level waste tanks

International Nuclear Information System (INIS)

1994-09-01

Oak Ridge National Laboratory facilities have produced liquid low-level waste (LLLW) that is radioactive and/or hazardous. Storage tanks have been used to collect and store these wastes. Most of the collection system, including the tanks, is located below the ground surface. Many of the systems have been removed from service (i.e., are not inactive) but contain residual amounts of waste liquid and sludges. A plan of action has been developed by DOE to ensure that environmental impacts from the waste remaining in the inactive tanks system are minimized. The Federal Facility Agreement (FFA) does not require any type of testing or monitoring for the inactive LLLW tanks that are removed from service but does require waste characterization of tanks contents, risk characterization of tanks removed from service, and remediation of the inactive tanks and their contents. This report is form information only and is not required by the FFA. It includes a description of the methodology and results of level trend analyses for the Category D tanks listed in the FFA that currently belong to the Environmental Restoration Program

Evaporation studies on Oak Ridge National Laboratory liquid low-level waste

Energy Technology Data Exchange (ETDEWEB)

Fowler, V.L. [PAI Corp., Oak Ridge, TN (United States); Perona, J.J. [Oak Ridge National Lab., TN (United States)

1993-03-01

Evaporation studies were performed with Melton Valley storage tank liquid low-level radioactive waste concentrate and with surrogates (nonradioactive) to determine the feasibility of a proposed out-of-tank-evaporation project. Bench-scale tests indicated that volume reductions ranging from 30 to 55% could be attained. Vendor-site tests were conducted (with surrogate waste forms) using a bench-scale single-stage, low-pressure (subatmospheric), low-temperature (120 to 173{degree}F) evaporator similar to units in operation at several nuclear facilities. Vendor tests were successful; a 30% volume reduction was attained with no crystallization of solids and no foaming, as would be expected from a high pH solution. No fouling of the heat exchanger surfaces occurred during these tests. It is projected that 52,000 to 120,000 gal of water could be evaporated from the supernate stored in the Melton and Bethel Valley liquid low-level radioactive waste (LLLW) storage tanks with this type of evaporator.

On-Site Decontamination System for Liquid Low Level Radioactive Waste - 13010

Energy Technology Data Exchange (ETDEWEB)

OSMANLIOGLU, Ahmet Erdal [Cekmece Nuclear Research and Training Center, Kucukcekmece Istanbul (Turkey)

2013-07-01

This study is based on an evaluation of purification methods for liquid low-level radioactive waste (LLLW) by using natural zeolite. Generally the volume of liquid low-level waste is relatively large and the specific activity is rather low when compared to other radioactive waste types. In this study, a pilot scale column was used with natural zeolite as an ion exchanger media. Decontamination and minimization of LLLW especially at the generation site decrease operational cost in waste management operations. Portable pilot scale column was constructed for decontamination of LLW on site. Effect of temperature on the radionuclide adsorption of the zeolite was determined to optimize the waste solution temperature for the plant scale operations. In addition, effect of pH on the radionuclide uptake of the zeolite column was determined to optimize the waste solution pH for the plant scale operations. The advantages of this method used for the processing of LLLW are discussed in this paper. (authors)

Laboratory simulation of high-level liquid waste evaporation and storage

International Nuclear Information System (INIS)

Anderson, P.A.

1978-01-01

The reprocessing of nuclear fuel generates high-level liquid wastes (HLLW) which require interim storage pending solidification. Interim storage facilities are most efficient if the HLLW is evaporated prior to or during the storage period. Laboratory evaporation and storage studies with simulated waste slurries have yielded data which are applicable to the efficient design and economical operation of actual process equipment

Future extension of the Swedish repository for low and intermediate level waste (SFR)

International Nuclear Information System (INIS)

Carlsson, Jan

2006-01-01

The existing Swedish repository for low and intermediate level waste (SFR) is licensed for disposal of short-lived waste originated from operation and maintenance of Swedish nuclear power plants. The repository is foreseen to be extended to accommodate short-lived waste from the future decommissioning of the Nuclear Power Plants. Long-lived waste from operation, maintenance and eventually decommissioning will be stored some years before disposal in a geological repository. This repository can be build either as a further extension of the SFR facility or as a separate repository. This paper discusses the strategy of a step-wise extended repository where the extensions are performed during operation of the existing parts of the repository. It describes the process for licensing new parts of the repository (and re-license of the existing parts). (author)

Strategic review on management and disposal of low- and intermediate-level solid radwastes

International Nuclear Information System (INIS)

Li Xuequn

1993-01-01

An overview on the actual status of solid low- and intermediate-level wastes (L/ILW) management in China is described. Some of the main problems at present are analysed. The strategies on management and disposal of the wastes are discussed in light of systematology. A large amount of solid L/ILW and distilled residual solution to be solidified have been accumulated during the past 30 years development of nuclear industry in China. These wastes, containing fission products, activated products, and uranium and transuranium elements respectively, mainly come from nuclear reactors, spent fuel reprocessing plants, and nuclear fuel fabrication plants. In the century, solid L/ILW and solidified wastes are produced mainly by nuclear industry; but in the next century, solid wastes will be steadily produced mainly from nuclear power plants

Influence of time dependent effects on the disposal environments of low and intermediate level radioactive wastes

International Nuclear Information System (INIS)

1984-12-01

Reviews are presented firstly of potential events and processes which may affect the evolution of the disposal environments of low and intermediate level radioactive wastes in Britain and secondly of previous studies carried out worldwide in the field of time dependent effects. From the latter review available methodologies for incorporating time dependence into radiological assessments are identified. Finally, proposals are presented for the design and development of a time dependent effects model, based on the existing far field state model (FFSM) developed for ONWI in USA. (author)

Acceptability of a low and intermediate level radioactive waste repository

International Nuclear Information System (INIS)

Zeleznik, N.; Polic, M.

2000-01-01

Siting of a radioactive waste repository, even for the waste of low and intermediate level (LILW) radioactivity, presents a great problem in almost every country that produces such waste. The main problem is not a technical one, but socio-psychological, namely the acceptability of this kind of repository. In general, people are opposed to any such kind of facility in their vicinity (NIMBY). In this study we try to establish the factors that influence people's behavior regarding the construction of a radioactive waste repository in their local community, with the use of Ajzen's model of planned behavior. Two different scenarios about the construction of a radioactive waste repository in their community, together with a set of questions were presented to participants from different schools. Data from the survey were analysed by multivariate methods, and a model of relevant behaviour was proposed. From the results it can be seen that different approaches to local community participation in site selection process slightly influence people's attitudes towards the LILW repository, while significant differences in answers were found in the responses which depend on participants' knowledge. Therefore the RAO Agency will further intensify preparation of the relevant communication plan and start with its implementation to support LILW repository site selection process, which will also include educational programme. (author)

Corrosion behaviour of steel rebars embedded in a concrete designed for the construction of an intermediate-level radioactive waste disposal facility

Directory of Open Access Journals (Sweden)

Schulz F.M.

2013-07-01

Full Text Available The National Atomic Energy Commission of the Argentine Republic is developing a nuclear waste disposal management programme that contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive wastes. The repository is based on the use of multiple, independent and redundant barriers. The major components are made in reinforced concrete so, the durability of these structures is an important aspect for the facility integrity. This work presents an investigation performed on an instrumented reinforced concrete prototype specifically designed for this purpose, to study the behaviour of an intermediate level radioactive waste disposal facility from the rebar corrosion point of view. The information obtained will be used for the final design of the facility in order to guarantee a service life more or equal than the foreseen durability for this type of facilities.

Feasibility study for the disposal of low and intermediate level radioactive waste in Cuba

International Nuclear Information System (INIS)

Chales Suarez, G.; Peralta Vital, J.L.; Gil Castillo, R.; Franklin Saburido, R.; Rodriquez Reyes, A.; Castillo Gomez, R.

1998-01-01

The perspective of completing and operating the Juragua Nuclear Power Station and the development of nuclear applications justifies the need to establish an appropriate low and intermediate level radioactive waste disposal system in Cuba. The design of one option which is consonant with the characteristics of this country is presented in the form of a feasibility study. The study discusses the characteristics of the wastes, the design of the repository, the packaging of the radioactive wastes as well as the siting, conditioning and performance assessment in a preliminary stage. International practice and experience have been considered, as well as the recommendations of the International Atomic Energy Agency [1-4] in the preparation of this study. (author)

The method for simultaneous extraction and back extraction in liquid three-phase system and equipment for simultaneous extraction and back extraction in liquid three-phase system

International Nuclear Information System (INIS)

Palyska, W.; Chmielewski, A.G.

1992-01-01

The method for simultaneous extraction and back extraction in liquid three-phase system has been worked out. The equipment designed for that process has been also subject of the patent. The interesting component is extracted first to intermediate phase consists of magnetic solvent keeping two extracting phases separately. The intermediate magnetic liquid has been kept in its position using a stable magnet maintained on the surface of the extraction vessel. Then the component pass from intermediate phase to the third phase as a result of back extraction. Mixing in the extraction and back extraction zones is organized by means of rotating shaft going along the whole apparatus. The extraction and back extraction processes occur simultaneously as a result of continuous flow of solvent in their zones. The single extraction back extraction facilities can be joined in larger batteries. 3 figs

Monitoring of low-level radioactive liquid effluent in Tokai reprocessing plant

International Nuclear Information System (INIS)

Mizutani, Tomoko; Koarashi, Jun; Takeishi, Minoru

2009-01-01

The Tokai reprocessing plant (TRP), the first reprocessing plant in Japan, has discharged low-level liquid wastes to the Pacific Ocean since the start of its operation in 1977. We have performed liquid effluent monitoring to realize an appropriate radioactive discharge control. Comparing simple and rapid analytical methods with labor-intensive radiochemical analyses demonstrated that the gross-alpha and gross-beta activities agreed well with the total activities of plutonium isotopes ( 238 Pu and 239+240 Pu) and major beta emitters (e.g., 90 Sr and 137 Cs), respectively. The records of the radioactive liquid discharge from the TRP showed that the normalized discharges of all nuclides, except for 3 H, were three or four orders of magnitude lower than those from the Sellafield and La Hague reprocessing plants. This was probably due to the installation of multistage evaporators in the liquid waste treatment process in 1980. The annual public doses for a hypothetical person were estimated to be less than 0.2 μSv y -1 from the aquatic pathway. Plutonium radioactivity ratios ( 238 Pu/ 239+240 Pu) of liquid effluents were determined to be 1.3-3.7, while those of the seabed sediment samples collected around the discharge point were 0.003-0.059, indicating no remarkable accumulation of plutonium in the regional aquatic environment. Thus, we concluded that there were no significant radiological effects on the public and the aquatic environment during the past 30-year operation of the TRP. (author)

40 Years of Experience of NIRAS / Belgoprocess on the Interim Storage of Low, Intermediate and High Level Waste

International Nuclear Information System (INIS)

Braeckeveldt, Marnix; Ghys, Bart

2016-01-01

Conclusion: • ONDRAF/NIRAS and Belgoprocess have gained over time an extended experience on the interim storage of Low-Intermediate and High level waste. • An systematic inspection strategy was developed in order the verify the conformity of the different waste-packages and corrective measures were taken to guarantee safe storage conditions. • From 2022 , ONDRAF/NIRAS will operate a surface disposal facility for LLW

Performance analysis of a repository for low and intermediate level reactor waste

International Nuclear Information System (INIS)

Vieno, T.; Nordman, H.; Vuori, S.; Peltonen, E.

1987-01-01

In Finland, utilities producing nuclear energy are responsible for the management of the radioactive waste, including final disposal. As regards low and intermediate level waste, the approach has been adopted to employ the power plant sites for locations of repositories. The repositories will be excavated at the depth of about 50 to 125 m in the bedrock of the two Finnish nuclear power plant sites, Loviisa and Olkiluoto. The performance analysis presented in this paper has been carried out for the Preliminary Safety Analysis Report (PSAR) of the Olkiluoto repository. A flexible model has been developed to estimate the release of radionuclides from waste packages and their subsequent transport through the engineered barriers in the repository. Gradual degradation of the engineered barriers is accounted for by altering parameters at fixed time points. Safety margins of the disposal concept have been evaluated by including disturbed evolution scenarios in the analysis. 13 references, 10 figures, 2 tables

Status of the NA62 liquid krypton electromagnetic calorimeter Level 0 trigger processor

CERN Document Server

Bonaiuto, V; Fucci, A; Paoluzzi, G; Salamon, A; Salina, G; Santovetti, E; Sargeni, F; Venditti, S

2013-01-01

The NA62 experiment at the CERN SPS aims to measure the Branching Ratio of the very rare kaon decay K(+)→π(+)νbar nu collecting O(100) events with a 10% background in two years of data taking. To reject the K(+)→π(+)π(0) background the NA48 liquid krypton calorimeter will be used in the 1-10 mrad angular region. The status of the Liquid Krypton Electromagnetic Calorimeter Level 0 Trigger is presented.

Continuous liquid level detection based on two parallel plastic optical fibers in a helical structure

Science.gov (United States)

Zhang, Yingzi; Hou, Yulong; Zhang, Yanjun; Hu, Yanjun; Zhang, Liang; Gao, Xiaolong; Zhang, Huixin; Liu, Wenyi

2018-02-01

A simple and low-cost continuous liquid-level sensor based on two parallel plastic optical fibers (POFs) in a helical structure is presented. The change in the liquid level is determined by measuring the side-coupling power in the passive fiber. The side-coupling ratio is increased by just filling the gap between the two POFs with ultraviolet-curable optical cement, making the proposed sensor competitive. The experimental results show that the side-coupling power declines as the liquid level rises. The sensitivity and the measurement range are flexible and affected by the geometric parameters of the helical structure. A higher sensitivity of 0.0208 μW/mm is acquired for a smaller curvature radius of 5 mm, and the measurement range can be expanded to 120 mm by enlarging the screw pitch to 40 mm. In addition, the reversibility and temperature dependence are studied. The proposed sensor is a cost-effective solution offering the advantages of a simple fabrication process, good reversibility, and compensable temperature dependence.

Digital low level rf control system with four different intermediate frequencies for the International Linear Collider

Science.gov (United States)

Wibowo, Sigit Basuki; Matsumoto, Toshihiro; Michizono, Shinichiro; Miura, Takako; Qiu, Feng; Liu, Na

2017-09-01

A field programmable gate array-based digital low level rf (LLRF) control system will be used in the International Linear Collider (ILC) in order to satisfy the rf stability requirements. The digital LLRF control system with four different intermediate frequencies has been developed to decrease the required number of analog-to-digital converters in this system. The proof of concept of this technique was demonstrated at the Superconducting RF Test Facility in the High Energy Accelerator Research Organization, Japan. The amplitude and phase stability has fulfilled the ILC requirements.

Performance of backfill materials in near surface disposal facilities for low and intermediate level radwaste. Appendix 4: China (a)

International Nuclear Information System (INIS)

Cunli, G.; Yawen, H.; Zhiwen, F.; Anxi, C.; Xiuzhen, L.; Jinsheng, Z.

2001-01-01

Full text: Backfill material is an important component of a multi-barriered disposal facility for low and intermediate level radioactive waste. This appendix describes the work concerning 'performance study on engineering materials of shallow land disposal of low and intermediate level radwaste'. At the time of the CRP, China had planned to establish five regional disposal sites for low-and-intermediate level radioactive waste. According to the potential distribution of these sites, forty-three sampling points were selected through information survey and table discussion. After field survey and screening, eight of them were selected for further studies in laboratory. Basic physical and chemical properties of each sample were measured in laboratory. The results indicate that no one of the samples can individually function as the backfill material in a multi-barriered near surface facility. Then nine additives for adsorption modification were tested using a static method. Further adsorption tests were conducted: three additives screened out in previous experiment were evaluated using the static method. Results obtained show that the Kd values of mixtures of 90% NW-3 and 10% BC for Co-60, Cs-134 and Sr-85, compared with those of 100% NW-3, are 4.8, 4.6 and 4.7 times higher, respectively. Effects of contact time, pH of tracer solutions and radionuclide concentrations of tracer solutions on Kd values of three samples, NW-3, BC and 90% NW-3 with 10% BC, were also be evaluated using the static method. Column tests were performed to evaluate migration of Co-60, Cs-134 and Sr-85 in NW-3 columns with different densities. The column tests were carried out for 210 days. However, no breakthrough was obtained. Long term performance of backfill materials was assessed through natural analogue. We compared Chinese ancient tombs with near-surface low and intermediate level radioactive waste (LILW) disposal facilities. Both were designed based upon multi-barrier principle. Then three

Passive Avoidance Training and Recall are Associated With Increased Glutamate Levels in the Intermediate Medial Hyperstriatum Ventrale of the Day-Old Chick

Directory of Open Access Journals (Sweden)

Jonathan N. Daisley

1998-01-01

glutamate levels in the intermediate medial hyperstriatum ventrale accompany pecking at either the water- or the methylanthranylate-bead. The taste of the aversant may be responsible for the greater increases found in methylanthranylate-trained birds.

Composite ion-exchangers and their possible use in treatment of low/intermediate level liquid radioactive wastes

International Nuclear Information System (INIS)

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

1993-01-01

A new method of preparation of composite inorganic-organic ion exchangers using modified polyacrylonitrile (PAN) as a binding polymer for the inorganic active component is described. This method enables incorporation of very fine to colloidal particles of active component in the binding polymer which increases the capacity and improves the kinetics of ion exchange of the resulting absorber. The proposed method can be applied on most of the inorganic ion exchangers known. Results of tests of some absorbers for treatment of radioactive wastes produced in the nuclear industry are given. For the removal of radiocesium from Long Term Fuel Storage Pond water at NPP Jaslovske Bohunice (Slovakia) NiFC-PAN composite ion exchanger has been tested. Excellent results have been achieved both at low and high (floating bed) flow rates in the course of treatment of up to 45,000 BV of pond water. The possibility of decreasing the total activity of the Biological Shield water from the same NPP below the 37 Bq/l discharge limit has been proved using NiFC-PAN and NaTiO-PAN composite ion exchangers. NiFC-PAN, NaTiO-PAN, MnO-PAN, M315-PAN and Na-Y-PAN composite ion exchangers were tested for removal of radiocesium, radiocobalt and radiomanganese from standard liquid radioactive wastes and concentrates from NPP Krsko, Croatia. Different combinations of absorbers have been tested for the treatment of Boron Recycle Hold-up, Waste Condensate and Waste Hold-up Tanks. Radium could be quantitatively removed from highly saline acid waste water from uranium underground leaching on Ba(Ca)SO 4 -PAN absorber

Determination of the plutonium contamination level in biological samples by liquid scintillation

International Nuclear Information System (INIS)

Willemot, J.M.; Verry, M.; Lataillade, G.

1989-01-01

Usual radiochemical processes are unable to carry out without delay the very large number of analyses as required in plutonium toxicology studies. Liquid scintillation is the best method to quickly determine plutonium contamination levels in most various samples (bone, organs,...) [fr

Comparison of different methods for liquid level adjustment in tank prover calibration

International Nuclear Information System (INIS)

Garcia, D A; Farias, E C; Gabriel, P C; Aquino, M H; Gomes, R S E; Aibe, V Y

2015-01-01

The adjustment of the liquid level during the calibration of tank provers with fixed volume is normally done by overfill but it can be done in different ways. In this article four level adjustment techniques are compared: plate, pipette, ruler and overfill adjustment. The adjustment methods using plate and pipette presented good agreement with the tank's nominal volume and lower uncertainty among the tested methods

US and Russian innovative technologies to process low-level liquid radioactive wastes: The Murmansk initiative

International Nuclear Information System (INIS)

Dyer, R.S.; Duffey, R.B.; Penzin, R.; Sorlie, A.

1996-01-01

This paper documents the status of the technical design for the upgrade and expansion to the existing Low-level Liquid Radioactive Waste (LLLRW) treatment facility in Murmansk, the Russian Federation. This facility, owned by the Ministry of Transportation and operated by the Russian company RTP Atomflot in Murmansk, Russia, has been used by the Murmansk Shipping Company (MSCo) to process low-level liquid radioactive waste generated by the operation of its civilian icebreaker fleet. The purpose of the new design is to enable Russia to permanently cease the disposal at sea of LLLRW in the Arctic, and to treat liquid waste and high saline solutions from both the Civil and North Navy Fleet operations and decommissioning activities. Innovative treatments are to be used in the plant which are discussed in this paper

A survey of possible microbiological effects within shallow land disposal sites designed to accept intermediate-level radioactive wastes

International Nuclear Information System (INIS)

Rushbrook, P.E.

1985-01-01

A literature survey was conducted to assess the current knowledge on microbial activity that may occur within a shallow intermediate-level waste disposal trench. Relatively little published information exists that is directly based on intermediate radioactive wasteforms, but relevant work was identified from other scientific fields. The likely environmental conditions within a disposal trench and their influence on microbial activity are considered. Also discussed are specific microbiological effects on waste packagings, backfill materials and concrete structures. Overall, it is unlikely that there will be extensive activity within the trenches and little evidence exists to suggest microbiologically-enhanced radionuclide migration,. The quantitative effect of microbial action is not possible to ascertain from the literature, but the general impression is that it will be low. Physical or chemical degradation processes are likely to predominate over those of a microbiological nature. Areas where further research would be valuable are also recommended. (author)

State-of-the-art for liquid-level measurements applied to in-vessel coolant level for nuclear reactors

International Nuclear Information System (INIS)

Anderson, R.L.

1980-01-01

The TMI-2 accident indicated that a direct indication of the liquid level in the reactor vessel would have told the operators that the core was being uncovered. This state-of-the-cost survey covered the following methods: heated thermocouple, differential pressure, ultrasonic, capacitance, microwave, time-domain reflectometry, and externally mounted radiation detectors

Modeling and Analysis on Radiological Safety Assessment of Low- and Intermediate Level Radioactive Waste Repository

Energy Technology Data Exchange (ETDEWEB)

Lee, Youn Myoung; Jung, Jong Tae; Kang, Chul Hyung (and others)

2008-04-15

Modeling study and analysis for technical support for the safety and performance assessment of the low- and intermediate level (LILW) repository partially needed for radiological environmental impact reporting which is essential for the licenses for construction and operation of LILW has been fulfilled. Throughout this study such essential area for technical support for safety and performance assessment of the LILW repository and its licensing as gas generation and migration in and around the repository, risk analysis and environmental impact during transportation of LILW, biosphere modeling and assessment for the flux-to-dose conversion factors for human exposure as well as regional and global groundwater modeling and analysis has been carried out.

Modeling and Analysis on Radiological Safety Assessment of Low- and Intermediate Level Radioactive Waste Repository

International Nuclear Information System (INIS)

Lee, Youn Myoung; Jung, Jong Tae; Kang, Chul Hyung

2008-04-01

Modeling study and analysis for technical support for the safety and performance assessment of the low- and intermediate level (LILW) repository partially needed for radiological environmental impact reporting which is essential for the licenses for construction and operation of LILW has been fulfilled. Throughout this study such essential area for technical support for safety and performance assessment of the LILW repository and its licensing as gas generation and migration in and around the repository, risk analysis and environmental impact during transportation of LILW, biosphere modeling and assessment for the flux-to-dose conversion factors for human exposure as well as regional and global groundwater modeling and analysis has been carried out

LIQUID-LIQUID EXTRACTION COLUMNS

Science.gov (United States)

Thornton, J.D.

1957-12-31

This patent relates to liquid-liquid extraction columns having a means for pulsing the liquid in the column to give it an oscillatory up and down movement, and consists of a packed column, an inlet pipe for the dispersed liquid phase and an outlet pipe for the continuous liquid phase located in the direct communication with the liquid in the lower part of said column, an inlet pipe for the continuous liquid phase and an outlet pipe for the dispersed liquid phase located in direct communication with the liquid in the upper part of said column, a tube having one end communicating with liquid in the lower part of said column and having its upper end located above the level of said outlet pipe for the dispersed phase, and a piston and cylinder connected to the upper end of said tube for applying a pulsating pneumatic pressure to the surface of the liquid in said tube so that said surface rises and falls in said tube.

LIQUIDITY MANAGING A CURRENT JOB OF BANKING MANAGEMENT

Directory of Open Access Journals (Sweden)

MEDAR LUCIAN-ION

2014-02-01

Full Text Available A credit institution liquidity managing, concerns on currency flows and operative funding needs, for customer satisfaction. Correlating bank liabilities and assets reflects the overall picture of the liquidity situation. The purpose of an efficient management of bank liquidity is to ensure the normal course of banking intermediation, to protect the interests of customers on one side and of the shareholders on the other side. Through an efficient bank liquidity management, are ensured reserve requirements and especially reasonable banking capacity of deposits reimbursement to customers, correlated with period in which they are or there are not returned to the credit institution, investments in the loans and other assets.

Functions and Requirements for Automated Liquid Level Gauge Instruments in Single-Shell and Double-Shell Tank Farms

International Nuclear Information System (INIS)

CARPENTER, K.E.

1999-01-01

This functions and requirements document defines the baseline requirements and criteria for the design, purchase, fabrication, construction, installation, and operation of automated liquid level gauge instruments in the Tank Farms. This document is intended to become the technical baseline for current and future installation, operation and maintenance of automated liquid level gauges in single-shell and double-shell tank farms

Solvent extraction in the treatment of acidic high-level liquid waste : where do we stand?

International Nuclear Information System (INIS)

Horwitz, E. P.; Schulz, W. W.

1998-01-01

During the last 15 years, a number of solvent extraction/recovery processes have been developed for the removal of the transuranic elements, 90 Sr and 137 Cs from acidic high-level liquid waste. These processes are based on the use of a variety of both acidic and neutral extractants. This chapter will present an overview and analysis of the various extractants and flowsheets developed to treat acidic high-level liquid waste streams. The advantages and disadvantages of each extractant along with comparisons of the individual systems are discussed

Monitoring PWR reactor vessel liquid level with SPNDs during LOCAs

International Nuclear Information System (INIS)

Adams, J.P.

1982-01-01

Data from in-core self-powered neutron detectors taken during two nuclear loss-of-coolant accident simulations have been correlated with core moderator density changes. The detector current attenuation has been calculated during blowdown and reflood phases of the simulation. Based on these data, it is concluded that these detectors could be used to monitor reactor vessel liquid level during loss-of-coolant accidents in pressurized water reactors

Treatment, conditioning and packaging for final disposal of low and intermediate level waste from Cernavoda: a techno-economic assessment

Energy Technology Data Exchange (ETDEWEB)

Suryanarayan, S.; Husain, A. [Kinectrics Inc., Toronto, ON (Canada); Fellingham, L.; Nesbitt, V. [Nuvia Ltd., Didcot, Oxfordshire (United Kingdom); Toro, L. [Mate-fin, Bucharest (Romania); Simionov, V.; Dumitrescu, D. [Cernavoda Nuclear Power Plant, Cernavoda (Romania)

2011-07-01

National Nuclearelectrica Society (SNN) owns and operates two CANDU-6 plants at Cernavoda in Romania. Two additional units are expected to be built on the site in the future. Low and intermediate level short-lived radioactive wastes from Cernavoda are planned to be disposed off in a near-surface repository to be built at Saligny. The principal waste streams are IX resins, filters, compactable wastes, non-compactables, organic liquids and oil-solid mixtures. Their volumetric generation rates per reactor unit are estimated to be: IX resins (6 m{sup 3}/y), filters (2 m{sup 3}/y), compactables (23 m{sup 3}/y) and non-compactables (15 m{sup 3}/y). A techno-economic assessment of the available options for a facility to treat and condition Cernavoda's wastes for disposal was carried out in 2009 based on projected waste volumes from all four units. A large number of processes were first screened to identify viable options. They were further considered to develop overall processing options for each waste stream. These were then consolidated to obtain options for the entire plant by minimizing the number of unit operations required to process the various waste streams. A total of 9 plant options were developed for which detailed costing was undertaken. Based on a techno-economic assessment, two top ranking plant options were identified. Several scenarios were considered for implementing these options. Amongst them, a contractor run operation of a facility located on the Cernavoda site was considered to be more cost effective than operating the facility using SNN personnel. (author)

Treatment of low-level radioactive waste liquid by reverse osmosis

International Nuclear Information System (INIS)

Buckley, L.P.; Sen Gupta, S.K.; Slade, J.A.

1995-01-01

The processing of low-level radioactive waste (LLRW) liquids that result from operation of nuclear power plants with reverse osmosis systems is not common practice. A demonstration facility is operating at Chalk River Laboratories (of Atomic Energy of Canada Limited), processing much of the LLRW liquids generated at the site from a multitude of radioactive facilities, ranging from isotope production through decontamination operations and including chemical laboratory drains. The reverse osmosis system comprises two treatment steps--spiral wound reverse osmosis followed by tubular reverse osmosis--to achieve an average volume reduction factor of 30:1 and a removal efficiency in excess of 99% for most radioactive and chemical species. The separation allows the clean effluent to be discharged without further treatment. The concentrated waste stream of 3 wt% total solids is further processed to generate a solid product. The typical lifetimes of the membranes have been nearly 4000 hours, and replacement was required based on increased pressure drops and irreversible loss of permeate flux. Four years of operating experience with the reverse osmosis system, to demonstrate its practicality and to observe and record its efficiency, maintenance requirements and effectiveness, have proven it to be viable for volume reduction and concentration of LLRW liquids generated from nuclear-power-plant operations

Design and construction of an optical sensor for liquid level control

International Nuclear Information System (INIS)

Razani, M.; Golnabi, H.; Dabbaghian, M. H.; Dariani, R. S.; Vaziri, N.; Hojabri, A.

2010-01-01

Design and construction of an optical sensor for liquid level control is reported here. Operation of this sensor is based on the intensity modulation. The modulated light intensity is detected by total internal reflection in a prism. The variation of output intensity is measured by an optical detector and is monitored by a digital voltmeter. This optical fiber sensor is used for water level measurement in this experiment. For a white light source, the output voltage in the case of low water level is equal to 480 mV and when the water level reaches to prism reduced to 8 mV. Height measurement accuracy in this system is about ±1mm.

Biodegradation of imidazolium ionic liquids by activated sludge microorganisms.

Science.gov (United States)

Liwarska-Bizukojc, Ewa; Maton, Cedric; Stevens, Christian V

2015-11-01

Biological properties of ionic liquids (ILs) have been usually tested with the help of standard biodegradation or ecotoxicity tests. So far, several articles on the identification of intermediate metabolites of microbiological decay of ILs have been published. Simultaneously, the number of novel ILs with unrecognized characteristics regarding biodegradability and effect on organisms and environment is still increasing. In this work, seven imidazolium ionic liquids of different chemical structure were studied. Three of them are 1-alkyl-3-methyl-imidazolium bromides, while the other four are tetra- or completely substituted imidazolium iodides. This study focused on the identification of intermediate metabolites of the aforementioned ionic liquids subjected to biodegradation in a laboratory activated sludge system. Both fully substituted ionic liquids and 1-ethyl-3-methyl-imidazolium bromide were barely biodegradable. In the case of two of them, no biotransformation products were detected. The elongation of the alkyl side chain made the IL more susceptible for microbiological decomposition. 1-Decyl-3-methyl-imidazolium bromide was biotransformed most easily. Its primary biodegradation up to 100 % could be achieved. Nevertheless, the cleavage of the imidazolium ring has not been observed.

Radiochemical methodologies applied to analytical characterization of low and intermediate level wastes from nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Monteiro, Roberto Pellacani G.; Júnior, Aluísio Souza R.; Kastner, Geraldo F.; Temba, Eliane S.C.; Oliveira, Thiago C. de; Amaral, Ângela M.; Franco, Milton B., E-mail: rpgm@cdtn.br, E-mail: reisas@cdtn.br, E-mail: gfk@cdtn.br, E-mail: esct@cdtn.br, E-mail: tco@cdtn.br, E-mail: ama@cdtn.br, E-mail: francom@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2017-07-01

The aim of this work is to present radiochemical methodologies developed at CDTN/CNEN in order to answer a program for isotopic inventory of radioactive wastes from Brazilian Nuclear Power Plants. In this program some radionuclides, {sup 3}H, {sup 14}C, {sup 55}Fe, {sup 59}Ni, {sup 63}Ni, {sup 90}Sr, {sup 93}Zr, {sup 94}Nb, {sup 99}Tc, {sup 129}I, {sup 235}U, {sup 238}U, {sup 238}Pu, {sup 239}+{sup 240}Pu, {sup 241}Pu, {sup 242}Pu, {sup 241}Am, {sup 242}Cm e {sup 243}+{sup 244}Cm, were determined in Low Level Wastes (LLW) and Intermediate Level Wastes (ILW) and a protocol of analytical methodologies based on radiochemical separation steps and spectrometric and nuclear techniques was established. (author)

Financial Intermediation and Economic Growth of Jordan 1964-1988

OpenAIRE

Magableh, Ali H.

1995-01-01

Until recently, the economics and financial literature placed little attention on the role that financial intermediation can play in accelerating the rate of economic development in less Developed Countries (LDCs). This has been changed now, however, where some instrumental role has been emphasised for financial intermediation in the process of economic development and growth. It is argued that an expansion of the financial system, size and intermediation in LDCs tends to increase the level o...

Handling and storage of high-level radioactive liquid wastes requiring cooling

International Nuclear Information System (INIS)

1979-01-01

The technology of high-level liquid wastes storage and experience in this field gained over the past 25 years are reviewed in this report. It considers the design requirements for storage facilities, describes the systems currently in use, together with essential accessories such as the transfer and off-gas cleaning systems, and examines the safety and environmental factors

Ultrasonic instrument for continuous measurement of liquid levels in sodium systems

International Nuclear Information System (INIS)

Boehmer, L.S.

1975-01-01

An ultrasonic level measurement system which provides a continuous digital readout over a range of 3-180 inches, was tested in 500 0 F liquid sodium. The system proved to be accurate and reliable, required no initial warm-up period and experienced no long term drift. Modifications can extend the present operating temperatures to greater than 1200 0 F

Progress in Low and Intermediate Level Operational Waste Characterization and Preparation for Disposal at Ignalina NPP

International Nuclear Information System (INIS)

Poskas, P.; Adomaitis, J. E.; Ragaisis, V.

2003-01-01

In Lithuania about 70-80% of all electricity is generated at a single power station, Ignalina NPP, which has two RBMK-1500 type reactors. Units 1 and 2 will be closed by 2005 and 2010, respectively, taking into account the conditions of the long-term substantial financial assistance rendered by the European Union, G-7 countries and other states as well as international institutions. The Government approved the Strategy on Radioactive Waste Management. Objectives of this strategy are to develop the radioactive waste management infrastructure based on modern technologies and provide for the set of practical actions that shall bring management of radioactive waste in Lithuania in compliance with radioactive waste management principles of IAEA and with good practices in force in European Union Member States. SKB-SWECO International-Westinghouse Atom Joint Venture with participation of Lithuanian Energy Institute has prepared a reference design of a near surface repository for short-lived low and intermediate level waste. This reference design is applicable to the needs in Lithuania, considering its hydro-geological, climatic and other environmental conditions and is able to cover the expected needs in Lithuania for at least thirty years ahead. Development of waste acceptance criteria is in practice an iterative process concerning characterization of existing waste, repository development, safety and environmental impact assessment etc. This paper describes the position in Lithuania with regard to the long-term management of low and intermediate level waste in the absence of finalized waste acceptance criteria and a near surface repository

The storage of liquid high level waste at BNFL, Sellafield. Addendum to February 2000 report

International Nuclear Information System (INIS)

2001-08-01

On 18 February 2000 the Health and Safety Executive (HSE) published a report on the work of its Nuclear Installations Inspectorate (NIl) in regulating the storage of liquid high level waste at the BNFL Sellafield site. Within the report NIl gave two undertakings. One was to publish an addendum around 1 year later covering its assessment of the new safety case for the storage plant and the second was to publish a further addendum when progress had been made with options studies for reducing the stocks of liquid high level waste (HLW), also referred to as highly active liquor (HAL), to a buffer level. A progress report was published in February 2001 which included a summary of the assessment of the new safety case and NIl's regulatory action to enforce liquid HLW stock reductions. This addendum provides a more detailed update on the position reached based on consideration of BNFL's responses to the recommendations from the February 2000 HLW report since its publication. It embodies the two addenda referred to above integrated into a single document for publication

Intermediate mass distribution of the dual resonance pomeron

International Nuclear Information System (INIS)

Chiu, C.B.; Matsuda, S.

1978-01-01

The intermediate mass distribution of the dual resonance pomeron is determined at the one-loop level and it is shown that the mass distribution obtained is remarkably similar to a suitably defined mass distribution in the dual multiperipheral model. Thus it is suggestive to identify the intermediate states of the dual resonance pomeron with multiperipheral processes. (Auth.)

Development of a partitioning method for the management of high-level liquid waste

International Nuclear Information System (INIS)

Kubota, M.; Dojiri, S.; Yamaguchi, I.; Morita, Y.; Yamagishi, I.; Kobayashi, T.; Tani, S.

1989-01-01

Fundamental studies especially focused on the separation of neptunium and technetium have been carried out to construct the advanced partitioning process of fractioning elements in a high-level liquid waste into four groups: transuranium elements, technetium-noble metals, strontium-cesium, and other elements. For the separation of neptunium by solvent extraction, DIDPA proved excellent for extracting Np(V), and its extraction rate was accelerated by hydrogen peroxide. Np(V) was found to be also separated quantitatively as precipitate with oxalic acid. For the separation of technetium, the denitration with formic acid was effective in precipitating it along with noble metals, and the adsorption with activated carbon was also effective for quantitative separation. Through these fundamental studies, the advanced partitioning process is presented as the candidate to be examined with an actual high-level liquid waste

Siting Criteria for Low and Intermediate Level Radioactive Waste Disposal in Egypt (Proposal approach)

International Nuclear Information System (INIS)

Abdellatif, M.M.

2012-01-01

The objective of radioactive waste disposal is to isolate waste from the surrounding media so that it does not result in undue radiation exposure to humans and the environment. The required degree of isolation can be obtained by implementing various disposal methods and suitable criteria. Near surface disposal method has been practiced for some decades, with a wide variation in sites, types and amounts of wastes, and facility designs employed. Experience has shown that the effective and safe isolation of waste depends on the performance of the overall disposal system, which is formed by three major components or barriers: the site, the disposal facility and the waste form. The site selection process for low-level and intermediate level radioactive waste disposal facility addressed a wide range of public health, safety, environmental, social and economic factors. Establishing site criteria is the first step in the sitting process to identify a site that is capable of protecting public health, safety and the environment. This paper is concerning a proposal approach for the primary criteria for near surface disposal facility that could be applicable in Egypt.

Numerical simulation of interface movement in gas-liquid two-phase flows with Level Set method

International Nuclear Information System (INIS)

Li Huixiong; Chinese Academy of Sciences, Beijing; Deng Sheng; Chen Tingkuan; Zhao Jianfu; Wang Fei

2005-01-01

Numerical simulation of gas-liquid two-phase flow and heat transfer has been an attractive work for a quite long time, but still remains as a knotty difficulty due to the inherent complexities of the gas-liquid two-phase flow resulted from the existence of moving interfaces with topology changes. This paper reports the effort and the latest advances that have been made by the authors, with special emphasis on the methods for computing solutions to the advection equation of the Level set function, which is utilized to capture the moving interfaces in gas-liquid two-phase flows. Three different schemes, i.e. the simple finite difference scheme, the Superbee-TVD scheme and the 5-order WENO scheme in combination with the Runge-Kutta method are respectively applied to solve the advection equation of the Level Set. A numerical procedure based on the well-verified SIMPLER method is employed to numerically calculate the momentum equations of the two-phase flow. The above-mentioned three schemes are employed to simulate the movement of four typical interfaces under 5 typical flowing conditions. Analysis of the numerical results shows that the 5-order WENO scheme and the Superbee-TVD scheme are much better than the simple finite difference scheme, and the 5-order WENO scheme is the best to compute solutions to the advection equation of the Level Set. The 5-order WENO scheme will be employed as the main scheme to get solutions to the advection equations of the Level Set when gas-liquid two-phase flows are numerically studied in the future. (authors)

Multi-shell spherical GaAs /AlxGa1-x As quantum dot shells-size distribution as a mechanism to generate intermediate band energy levels

Science.gov (United States)

Rodríguez-Magdaleno, K. A.; Pérez-Álvarez, R.; Martínez-Orozco, J. C.; Pernas-Salomón, R.

2017-04-01

In this work the generation of an intermediate band of energy levels from multi-shell spherical GaAs /AlxGa1-x As quantum dot shells-size distribution is reported. Within the effective mass approximation the electronic structure of a GaAs spherical quantum-dot surrounded by one, two and three shells is studied in detail using a numerically stable transfer matrix method. We found that a shells-size distribution characterized by continuously wider GaAs domains is a suitable mechanism to generate the intermediate band whose width is also dependent on the Aluminium concentration x. Our results suggest that this effective mechanism can be used for the design of wider intermediate band than reported in other quantum systems with possible solar cells enhanced performance.

Liquid emulsion scintillators which solidify for facile disposal

International Nuclear Information System (INIS)

O'Brien, R.E.; Krieger, J.K.

1981-01-01

A liquid organic scintillation cocktail is described which counts solutions of radiolabelled compounds containing up to ten % by volume of water with high efficiency and is readily polymerizable to a solid for easy disposal. The cocktail comprises a polymerizable organic solvent, a solubilizing agent, an intermediate solvent, and an organic scintillator. A method of disposing of liquid organic scintillation cocktail waste and a kit useful for practising the method are also described. (U.K.)

Design and construction of the low-level liquid waste treatment system

International Nuclear Information System (INIS)

Baker, M.N.; Mateer, W.E.; Metzler, G.H.; Reeves, S.R.; Rickettson, D.J.

1989-03-01

This report describes the design and construction of the Low-Level Liquid Waste Treatment System (LWTS). The LWTS is part of a system that will prepare High-Level Radioactive Waste for solidification in glass. This preparation includes removal of water and salts from the stored waste. The topics addressed are: the design objective to reuse the Process Building to contain LWTS, the special considerations that arise when building a new system inside a decontaminated facility, interface to existing plant systems, phased construction, and construction testing. 8 refs., 24 figs

Selective separation of cesium from simulated high level liquid waste solution using 1,3-dioctyloxy calix[4]arene-benzo-crown-6

International Nuclear Information System (INIS)

Vikas Kumar; Sharma, J.N.; Hubli, R.C.

2014-01-01

The 25,27-di(octyloxy)calix[4]arenebenzocrown-6 (CBC) in 1,3-alternate conformation was synthesized indigenously starting from its intermediates in good yield and purity. The extraction studies of CBC were carried out by using two different phase modifiers namely isodecyl alcohol and ortho-nitrophenyl hexyl ether. Detailed investigations on the effect of various parameters like, concentration of phase modifiers, aqueous phase acidity, ligand concentration, nitrate ion concentration and effect of temperature on extraction of cesium have been carried out. The concentration of phase modifiers was optimized to be 30 % in n-dodecane to ensure optimum extraction of cesium. Stoichiometry of the extracted complex determined by slope analysis method reveals 1:1:1 molar ratio for CsNO 3 :CBC:HNO 3 . The extraction process was found to be exothermic as determined from the plot of log K ex versus 1/T. The solvent system with a composition 0.01 M CBC/30 % phase modifier/n-dodecane was found to be effective for selective separation of cesium from simulated high level liquid waste solution. (author)

Determination of Na+ and K+ ions in the high-level liquid waste by ion chromatography (IC)

International Nuclear Information System (INIS)

Chen Lianzhong; Ma Guilan

1992-01-01

The determination of Na + and k + ions in the high-level liquid waste is investigated using ion chromatography. In order to protect the low capacity ion exchange resin in single column IC and remove the transition metal as well as other heavy metal ions that are contained in liquid waste, the pretreatment column with EDTA chelating resin is used. Those impurity metal ions are strongly absorbed by EDTA chelating resin and 100% of Na + and K + ions in the solution are eluted. The ability of the decontamination of EDTA chelating resin is satisfactory. The sample of the high-level liquid waste is diluted appropriately, then an aliquot of the sample is passed through the pretreatment column with EDTA chelating resin, the eluate is analysed by single column ion chromatography. The precision of this method is better than 5% for the determination of Na + and K + ions (at μg· ml -1 level)

Demonstration of pyropartitioning process by using genuine high-level liquid waste. Reductive-extraction of actinide elements from chlorination product

International Nuclear Information System (INIS)

Uozumi, Koichi; Iizuka, Masatoshi; Kurata, Masaki; Ougier, Michel; Malmbeck, Rikard; Winckel, Stefaan van

2009-01-01

The pyropartitioning process separates the minor actinide elements (MAs) together with uranium and plutonium from the high-level liquid waste generated at the Purex reprocessing of spent LWR fuel and introduces them to metallic fuel cycle. For the demonstration of this technology, a series experiment using 520g of genuine high-level liquid waste was started and the conversion of actinide elements to their chlorides was already demonstrated by denitration and chlorination. In the present study, a reductive extraction experiment in molten salt/liquid cadmium system to recover actinide elements from the chlorination product of the genuine high-level liquid waste was performed. The results of the experiment are as following; 1) By the addition of the cadmium-lithium alloy reductant, almost all of plutonium and MAs in the initial high-level liquid waste were recovered in the cadmium phase. It means no mass loss during denitration, chlorination, and reductive-extraction. 2) The separation factor values of plutonium, MAs, and rare-earth fission product elements versus uranium agreed with the literature values. Therefore, actinide elements will be separated from fission product elements in the actual system. Hence, the pyropartitioning process was successfully demonstrated. (author)

Experimental observations on electrorefining spent nuclear fuel in molten LiCl-KCl/liquid cadmium system

International Nuclear Information System (INIS)

Johnson, T. A.; Laug, D. V.; Li, S. X.; Sofu, T.

1999-01-01

Argonne National Laboratory (ANL) is currently performing a demonstration program for the Department of Energy (DOE) which processes spent nuclear fuel from the Experimental Breeder Reactor (EBR-II). One of the key steps in this demonstration program is electrorefining of the spent fuel in a molten LiCl-KCl/liquid cadmium system using a pilot scale electrorefiner (Mk-IV ER). This article summarizes experimental observations and engineering aspects for electrorefining spent fuel in the molten LiCl-KCl/liquid cadmium system. It was found that the liquid cadmium pool acted as an intermediate electrode during the electrorefining process in the ER. The cadmium level was gradually decreased due to its high vapor pressure and vaporization rate at the ER operational temperature. The low cadmium level caused the anode assembly momentarily to touch the ER vessel hardware, which generated a periodic current change at the salt/cathode interface and improved uranium recovery efficiency for the process. The primary current distributions calculated by numerical simulations were used in interpreting the experimental results

Levels of endogenous regulatory factors in liquidators of consequences of the Chernobyl accident

International Nuclear Information System (INIS)

Liasko, L.I.; Souchkevitch, G.N.; Tsyb, A.F.

1997-01-01

Dynamics of endogenous regulatory factor levels was studied in liquidators of consequences of the Chernobyl accident (mean age - 42 years). Irradiation dose for 90% of examined individuals was within 100 mSv range. We observed a decreased level of synthesis of intracellular processes regulators (cAMP, cGMP) and biased ratio of arachidonic acid metabolites (TxB2, 6-Keto-PGF1α) in persons worked in the zone of accident at different time during the period of 1986-1988. The parameters measured were preserved even 4 years later and the changes apparently did not depend on the individual's age and work conditions. However they were most pronounced in liquidators of 1986 and in those who stayed in the Chernobyl accident zone for a long time. There was no evident connection between the dose and extent of the parameter alterations. (author)

Stochastic and deterministic models to evaluate the critical distance of a near surface repository for the disposal of intermediate and low level radioactive wastes

Energy Technology Data Exchange (ETDEWEB)

Alves, A.S.M., E-mail: asergi@eletronuclear.gov.br [Eletrobrás Termonuclear – Eletronuclear S.A. , Rua da Candelária 65, 7° andar, GSN.T, 20091-906 Rio de Janeiro, RJ (Brazil); Melo, P.F. Frutuoso e, E-mail: frutuoso@nuclear.ufrj.br [Graduate Program of Nuclear Engineering, COPPE, Federal University of Rio de Janeiro, Av. Horácio Macedo 2030, Bloco G, sala 206, 21941-914 Rio de Janeiro, RJ (Brazil); Passos, E.M., E-mail: epassos@eletronuclear.gov.br [Eletrobrás Termonuclear – Eletronuclear S.A. , Rua da Candelária 65, 7° andar, GSN.T, 20091-906 Rio de Janeiro, RJ (Brazil); Fontes, G.S., E-mail: gsfontes@hotmail.com [Instituto Militar de Engenharia – IME, Praça General Tibúrcio 80, 22290-270 Rio de Janeiro, RJ (Brazil)

2015-06-15

Highlights: • The water infiltration scenario is evaluated for a near surface repository. • The main objective is the determination of the critical distance of the repository. • The column liquid height in the repository is governed by an Ito stochastic equation. • Practical results are obtained for the Abadia de Goiás repository in Brazil. - Abstract: The aim of this paper is to present the stochastic and deterministic models developed for the evaluation of the critical distance of a near surface repository for the disposal of intermediate (ILW) and low level (LLW) radioactive wastes. The critical distance of a repository is defined as the distance between the repository and a well in which the water activity concentration is able to cause a radiological dose to a member of the public equal to the dose limit set by the regulatory body. The mathematical models are developed based on the Richards equation for the liquid flow in the porous media and on the solute transport equation in this medium. The release of radioactive material from the repository to the environment is considered through its base and its flow is determined by Darcy's Law. The deterministic model is obtained from the stochastic approach by neglecting the influence of the Gaussian white noise on the rainfall and the equations are solved analytically with the help of conventional calculus (non-stochastic calculus). The equations of the stochastic model are solved analytically based on the Ito stochastic calculus and numerically by using the Euler–Maruyama method. The impact on the value of the critical distance of the Abadia de Goiás repository is analyzed, taken as a study case, when the deterministic methodology is replaced by the stochastic one, considered more appropriate for modeling rainfall as a stochastic process.

Summary report of a seminar on geosphere modelling requirements of deep disposal of low and intermediate level radioactive wastes

International Nuclear Information System (INIS)

Piper, D.; Paige, R.W.; Broyd, T.W.

1989-02-01

A seminar on the geosphere modelling requirements of deep disposal of low and intermediate level radioactive wastes was organised by WS Atkins Engineering Sciences as part of Her Majesty's Inspectorate of Pollution's Radioactive Waste Assessment Programme. The objectives of the seminar were to review geosphere modelling capabilities and prioritise, if possible, any requirements for model development. Summaries of the presentations and subsequent discussions are given in this report. (author)

Degradation of the drug sodium diclofenac by Trametes versicolor pellets and identification of some intermediates by NMR

Energy Technology Data Exchange (ETDEWEB)

Marco-Urrea, Ernest [Departament d' Enginyeria Quimica and Institut de Ciencia i Tecnologia Ambiental, Escola d' Enginyeria (Estonia), Universitat Autonoma de Barcelona (UAB), 08193 Bellaterra (Spain); Perez-Trujillo, Miriam [Servei de Ressonancia Magnetica Nuclear, UAB, 08193 Bellaterra (Spain); Cruz-Morato, Carles [Departament d' Enginyeria Quimica and Institut de Ciencia i Tecnologia Ambiental, Escola d' Enginyeria (Estonia), Universitat Autonoma de Barcelona (UAB), 08193 Bellaterra (Spain); Caminal, Gloria, E-mail: gloria.caminal@uab.es [Unitat de Biocatalisis Aplicada associada al IQAC (CSIC-UAB), EE, UAB, 08193 Bellaterra (Spain); Vicent, Teresa [Departament d' Enginyeria Quimica and Institut de Ciencia i Tecnologia Ambiental, Escola d' Enginyeria (Estonia), Universitat Autonoma de Barcelona (UAB), 08193 Bellaterra (Spain)

2010-04-15

Degradation of diclofenac sodium, a nonsteroidal anti-inflammatory drug widely found in the aquatic environment, was assessed using the white-rot fungus Trametes versicolor. Almost complete diclofenac removal ({>=}94%) occurred the first hour with T. versicolor pellets when the drug was added at relatively high (10 mg L{sup -1}) and environmentally relevant low (45 {mu}g L{sup -1}) concentrations in a defined liquid medium. In vivo and in vitro experiments using the cytochrome P450 inhibitor 1-aminobenzotriazole and purified laccase, respectively, suggested at least two different mechanisms employed by T. versicolor to initiate diclofenac degradation. Two hydroxylated metabolites, 4'-hydroxydiclofenac and 5-hydroxydiclofenac, were structurally elucidated by nuclear magnetic resonance as degradation intermediates in fungal cultures spiked with diclofenac. Both parent compound and intermediates disappeared after 24 h leading to a decrease in ecotoxicity calculated by the Microtox test. Laccase-catalyzed transformation of diclofenac led to the formation of 4-(2,6-dichlorophenylamino)-1,3-benzenedimethanol, which was not detected in in vivo experiments probably due to the low laccase activity levels observed through the first hours of incubation.

Degradation of the drug sodium diclofenac by Trametes versicolor pellets and identification of some intermediates by NMR

International Nuclear Information System (INIS)

Marco-Urrea, Ernest; Perez-Trujillo, Miriam; Cruz-Morato, Carles; Caminal, Gloria; Vicent, Teresa

2010-01-01

Degradation of diclofenac sodium, a nonsteroidal anti-inflammatory drug widely found in the aquatic environment, was assessed using the white-rot fungus Trametes versicolor. Almost complete diclofenac removal (≥94%) occurred the first hour with T. versicolor pellets when the drug was added at relatively high (10 mg L -1 ) and environmentally relevant low (45 μg L -1 ) concentrations in a defined liquid medium. In vivo and in vitro experiments using the cytochrome P450 inhibitor 1-aminobenzotriazole and purified laccase, respectively, suggested at least two different mechanisms employed by T. versicolor to initiate diclofenac degradation. Two hydroxylated metabolites, 4'-hydroxydiclofenac and 5-hydroxydiclofenac, were structurally elucidated by nuclear magnetic resonance as degradation intermediates in fungal cultures spiked with diclofenac. Both parent compound and intermediates disappeared after 24 h leading to a decrease in ecotoxicity calculated by the Microtox test. Laccase-catalyzed transformation of diclofenac led to the formation of 4-(2,6-dichlorophenylamino)-1,3-benzenedimethanol, which was not detected in in vivo experiments probably due to the low laccase activity levels observed through the first hours of incubation.

Intermediate- and short-range order in phosphorus-selenium glasses

International Nuclear Information System (INIS)

Bytchkov, Aleksei; Hennet, Louis; Price, David L.; Miloshova, Mariana; Bychkov, Eugene; Kohara, Shinji

2011-01-01

State-of-the-art neutron and x-ray diffraction measurements have been performed to provide a definitive picture of the intermediate- and short-range structures of P x Se 1-x glasses spanning two glass regions, x 0.025-0.54 and 0.64-0.84. Liquid P 4 Se 3 and amorphous red P and Se were also measured. Detailed information was obtained about the development with increasing phosphorous concentration of intermediate-range order on the length scale ∼6 A ring , based on the behavior of the first sharp diffraction peak. Attention is also paid to the feature in the structure factor at 7.5 A ring -1 , identified in earlier numerical simulations, provides further evidence of the existence of molecular units. The real-space transforms yield a reliable statistical picture of the changing short-range order as x increases, using the information about types and concentrations of local structural units provided by previous NMR measurements to interpret the trends observed.

An evaluation on the disposal alternatives for low- and intermediate- level radwaste (II)

International Nuclear Information System (INIS)

Park, Hun Hwee; Han, Kyung Won; Hahn, Pil Soo; Lee, Han Soo; Cho, Won Jin; Lee, Jae Dwan; Park, Chung Kyun; Lee, Myung Joo; Choi, Heui Joo; Lee, Youn Myoung

1988-02-01

An evaluation on the radioactive waste disposal alternatives for the low-and intermediate level wastes being produced from nuclear power generation and radioisotope application was carried out in view of the radiological safety, socio-political aspects and repository construction economics. Three types of possible alternatives-sample shallow land disposal method, engineered shallow land disposal method and engineered rock cavern disposal method are investigated. The safety assessment consists of radiological dose calculation and nonradiological impacts which is expressed as total number of injuries and fatalities during construction, operation and transportation. The sociopolitical assessment is done in terms of site conditions including easiness for land acquisition, technical feasibility and public acceptance. The economic assessment is performed by cost comparison regarding land acquisition, construction, operation and closure for each alternatives. The evaluation shows that engineered rock cavern disposal method has remarkable favour in safety than others. And also an integrated evaluation using AHP results the engineered rock cavern disposal method as the most favorable option

Tunable Quantum Spin Liquidity in the 1 /6 th-Filled Breathing Kagome Lattice

Science.gov (United States)

Akbari-Sharbaf, A.; Sinclair, R.; Verrier, A.; Ziat, D.; Zhou, H. D.; Sun, X. F.; Quilliam, J. A.

2018-06-01

We present measurements on a series of materials, Li2 In1 -xScx Mo3 O8 , that can be described as a 1 /6 th-filled breathing kagome lattice. Substituting Sc for In generates chemical pressure which alters the breathing parameter nonmonotonically. Muon spin rotation experiments show that this chemical pressure tunes the system from antiferromagnetic long range order to a quantum spin liquid phase. A strong correlation with the breathing parameter implies that it is the dominant parameter controlling the level of magnetic frustration, with increased kagome symmetry generating the quantum spin liquid phase. Magnetic susceptibility measurements suggest that this is related to distinct types of charge order induced by changes in lattice symmetry, in line with the theory of Chen et al. [Phys. Rev. B 93, 245134 (2016), 10.1103/PhysRevB.93.245134]. The specific heat for samples at intermediate Sc concentration, which have the minimum breathing parameter, show consistency with the predicted U (1 ) quantum spin liquid.

Action taken by ENRESA and the NPPs with a view to reducing the production of low and intermediate level wastes

International Nuclear Information System (INIS)

Morales, A.; Rojo, F.

1996-01-01

In those countries in which the responsibilities of the different organizations involved in the management of low and intermediate level radioactive wastes (Regulatory Body, Agency, Facility Operators and Producers) are perfectly defined and a definitive Waste Disposal Facility is in operation, the next phase in order of importance consists of addressing a waste volume reduction policy aimed at optimizing storage capacity

Liquid filter for liquids containing radioactive materials

International Nuclear Information System (INIS)

Rohleder, N.; Schwarz, F.

1986-01-01

A device for filtering radioactive liquids loaded with solids is described, which has a pressure-resistant housing with a lid and an incomer for the turbid liquid and a collecting space and drain for the filtrate at the bottom of the housing. A filter cartridge is present in this housing. Such a filtering device must be suitable for use in nuclear plants, must be easy to replace by remote control and must minimise the carrying over of radioactive particles. This problem should be solved by the filter cartridge consisting of a large number of horizontal filter plates stacked above one another, which carry a deep layer filter material acting in the sub-micron range. The turbid liquid runs into the centre of the stack of filter plates via a vertical central duct. The intermediate spaces between the filter places are connected to this central duct via the layer of filter material. The filter plates are sealed against one another on the outer circumference and have radial drain openings for the filtrate on the outside. The central duct is sealed at the lower end by a plate. When the filter cartridge is replaced, the radioactive waste in the filter cartridge remains safely enclosed and can be conditioned in suitable containers. (orig.) [de

Solidification of acidic liquid waste from 99Mo isotope production

International Nuclear Information System (INIS)

Parsons, G.J.

2001-01-01

Full text: The production of the radioisotope molybdenum-99 by the fission process began at ANSTO in the late 1960's. Molybdenum-99, with a half life of 66 hours, decays by beta emission to produce technetium-99m, a metastable isotope. Technetium-99m is the most widely used medical radioisotope due to its near ideal properties, particularly the radioactive half life of only 6 hours. ANSTO has been producing generators for around 30 years for distribution to hospitals and nuclear medicine centres. These generators produce technetium-99m for medical use by decay of the contained molybdenum-99. To produce molybdenum-99, uranium dioxide pellets enriched to 2.2% 235 U are irradiated in ANSTO's HIFAR reactor for about one week. The irradiated pellets are subsequently dissolved in nitric acid to allow the recovery of the molybdenum. An acidic intermediate level liquid waste results from this processing. A primary waste results from the raw leach solution (after removal of the molybdenum onto a packed alumina column) and a weaker secondary waste is produced from a series of column washing steps. The waste solution contains uranium, the majority of the other fission products and low levels of ammonia in a nitric acid solution. This liquid waste had been accumulating and stored in specially designed shielded tanks in a storage facility. A process has been developed at ANSTO to convert this intermediate level liquid waste into a crystalline solid form of considerably less volume and mass, for improved storage. The operation comprises three processing steps. The lower strength secondary waste solution first requires concentration, with the removal of water and some acid into a condensate. The condensate is chemically neutralised and treated through the conventional water treatment plant. Concentrated solution is then treated in a batch chemical process to reduce the low levels of ammonia to very low levels. The final evaporation process removes further water and acid and

Sulphate in Liquid Nuclear Waste: from Production to Containment

Energy Technology Data Exchange (ETDEWEB)

Lenoir, M.; Grandjean, A.; Ledieu, A.; Dussossoy, J.L.; Cau Dit Coumes, C.; Barre, Y.; Tronche, E. [CEA Marcoule, DEN/DTCD/SECM/LDMC, Batiment 208 BP17171, Bagnols sur Ceze, 30207 (France)

2009-06-15

Nuclear industry produces a wide range of low and intermediate level liquid radioactive wastes which can include different radionuclides such as {sup 90}Sr. In La Hague reprocessing plant and in the nuclear research centers of CEA (Commissariat a l'Energie Atomique), the coprecipitation of strontium with barium sulphate is the technique used to treat selectively these contaminated streams with the best efficiency. After the decontamination process, low and intermediate level activity wastes incorporating significant quantities of sulphate are obtained. The challenge is to find a matrix easy to form and with a good chemical durability which is able to confine this kind of nuclear waste. The current process used to contain sulphate-rich nuclear wastes is bituminization. However, in order to improve properties of containment matrices and simplify the process, CEA has chosen to supervise researches on other materials such as cements or glasses. Indeed, cements are widely used for the immobilization of a variety of wastes (low and intermediate level wastes) and they may be an alternative matrix to bitumen. Even if Portland cement, which is extensively used in the nuclear industry, presents some disadvantages for the containment of sulphate-rich nuclear wastes (risk of swelling and cracking due to delayed ettringite formation), other cement systems, such as calcium sulfo-aluminate binders, may be valuable candidates. Another matrix to confine sulphate-rich waste could be the glass. One of the advantages of this material is that it could also immobilize sulphate containing high level nuclear waste which is present in some countries. This waste comes from the use of ferrous sulfamate as a reducing agent for the conversion of Pu{sup 4+} to Pu{sup 3+} in the partitioning stage of the actinides during reprocessing. Sulphate solubility in borosilicate glasses has already been studied in CEA at laboratory and pilot scales. At a pilot scale, low level liquid waste has been

The principles of design of a shallow disposal site for low and intermediate level radioactive wastes

International Nuclear Information System (INIS)

Holmes, R.E.

1985-01-01

This paper addresses the principles of design of a shallow disposal site for low and intermediate level radioactive wastes. The objective of the author is to review the need for shallow land disposal facilities in the UK and to propose design principles which will protect the public and operatives from excessive risk. It is not the intent of the author to present a detailed design of facility which will meet the design standards proposed although such a design is feasible and within the scope of currently available technology. The principles and standards proposed in this paper are not necessarily those of PPC Consultant Services Ltd. or NEI Waste Technologies Ltd. (author)

Adapting the notion of natural (geological) barrier for final disposal of low- and intermediate-level radioactive wastes in Romania

International Nuclear Information System (INIS)

Durdun, I.; Marunteanu, C.; Andrei, V.

2001-01-01

According to the Minimum Disturbances Design (MDD) notion by Carl-Olof Morfeldt of Mineconsult, Sweden, any site selection, design and construction of low- and intermediate-level radioactive waste repository should be based on a thorough knowledge of the geological environmental so that the implantation of the disposal facility induce no significant harmful consequences. This work presents the way in which the Romanian program of radioactive waste management was implemented for disposal of low- and intermediate-level radioactive wastes from Cernavoda NPP. Based on geological criteria of selection of lithologic, petrographic, tectonic, seismologic, hydrologic and geo-technic nature, 37 sites were analyzed from which 2 were retained and finally one, Saligny site, was chosen, as the most close to Cernavoda NPP. Also, public acceptance and transport connections were taken into consideration. SUTRA, SWMS-2D and CHAIN-2D codes were applied to analyze the safety and the geological barrier effects. The barrier consists in red clay, a smectitic mineralogic compound. The computation showed that in Saligny vault the maximal tritium extension is kept inside due to the red clay barrier. Geo-technical engineering works were conducted to improve the properties of the loess upper layer which resulted in lowering its sensitivity to moistening and erosion

Ageing management program for the Spanish low and intermediate level waste disposal and spent fuel and high-level waste centralised storage facilities

Science.gov (United States)

Zuloaga, P.; Ordoñez, M.; Andrade, C.; Castellote, M.

2011-04-01

The generic design of the centralised spent fuel storage facility was approved by the Spanish Safety Authority in 2006. The planned operational life is 60 years, while the design service life is 100 years. Durability studies and surveillance of the behaviour have been considered from the initial design steps, taking into account the accessibility limitations and temperatures involved. The paper presents an overview of the ageing management program set in support of the Performance Assessment and Safety Review of El Cabril low and intermediate level waste (LILW) disposal facility. Based on the experience gained for LILW, ENRESA has developed a preliminary definition of the Ageing Management Plan for the Centralised Interim Storage Facility of spent Fuel and High Level Waste (HLW), which addresses the behaviour of spent fuel, its retrievability, the confinement system and the reinforced concrete structure. It includes tests plans and surveillance design considerations, based on the El Cabril LILW disposal facility.

Ageing management program for the Spanish low and intermediate level waste disposal and spent fuel and high-level waste centralised storage facilities

Directory of Open Access Journals (Sweden)

Andrade C.

2011-04-01

Full Text Available The generic design of the centralised spent fuel storage facility was approved by the Spanish Safety Authority in 2006. The planned operational life is 60 years, while the design service life is 100 years. Durability studies and surveillance of the behaviour have been considered from the initial design steps, taking into account the accessibility limitations and temperatures involved. The paper presents an overview of the ageing management program set in support of the Performance Assessment and Safety Review of El Cabril low and intermediate level waste (LILW disposal facility. Based on the experience gained for LILW, ENRESA has developed a preliminary definition of the Ageing Management Plan for the Centralised Interim Storage Facility of spent Fuel and High Level Waste (HLW, which addresses the behaviour of spent fuel, its retrievability, the confinement system and the reinforced concrete structure. It includes tests plans and surveillance design considerations, based on the El Cabril LILW disposal facility.

Intermediate storage facility for vitrified high level waste from the reprocessing of spent nuclear fuel

International Nuclear Information System (INIS)

1978-04-01

An intermediate storage facility for vitrified high level waste is described. The design was made specifically for Swedish conditions but can due to modular design be applied also for other conditions. Most of the plant is located underground with a rock cover of about 30 m in order to provide protection against external forces such as acts of war and sabotage. The storage area consists of four caverns each with 150 pits. Each pit can take 10 waste cylinders of 0.4 m diameter and 1.5 m length containing 150 liters of glass. The capacity can be increased by adding additional caverns. Cooling is obtained by forced air convection. Reception areas, auxiliary systems and operation of the plant are also described

Safe dry storage of intermediate-level waste at CRL

International Nuclear Information System (INIS)

Chiu, A.; Sanderson, T.; Lian, J.

2011-01-01

Ongoing operations at Atomic Energy of Canada Limited's (AECL) Chalk River Laboratories (CRL) generate High-, Intermediate- and Low-Level Waste (HLW, ILW and LLW) that will require safe storage for several decades until a long-term management facility is available. This waste is stored in below grade concrete structures (i.e. tile holes or bunkers) or the above-ground Shielded Modular Above Ground Storage (SMAGS) facility depending on the thermal and shielding requirements of the particular waste package. Existing facilities are reaching their capacity and alternate storage is required for the future storage of this radioactive material. To this end, work has been undertaken at CRL to design, license, construct and commission the next generation of waste management facilities. This paper provides a brief overview of the existing radioactive-waste management facilities used at CRL and focuses on the essential requirements and issues to be considered in designing a new waste storage facility. Fundamentally, there are four general requirements for a new storage facility to dry store dry non-fissile ILW. They are the need to provide: (1) containment, (2) shielding, (3) decay heat removal, and (4) ability to retrieve the waste for eventual placement in an appropriate long-term management facility. Additionally, consideration must be given to interfacing existing waste generating facilities with the new storage facility. The new facilities will be designed to accept waste for 40 years followed by 60 years of passive storage for a facility lifespan of 100 years. The design should be modular and constructed in phases, each designed to accept ten years of waste. This strategy will allow for modifications to subsequent modules to account for changes in waste characteristics and generation rates. Two design concepts currently under consideration are discussed. (author)

Chiral analysis of bambuterol, its intermediate and active drug in human plasma by liquid chromatography-tandem mass spectrometry: Application to a pharmacokinetic study.

Science.gov (United States)

Zhou, Ting; Liu, Shan; Zhao, Ting; Zeng, Jing; He, Mingzhi; Xu, Beining; Qu, Shanshan; Xu, Ling; Tan, Wen

2015-08-01

A sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed for simultaneous chiral analysis of an antiasthma drug bambuterol, its key intermediate monocarbamate bambuterol and its active drug terbutaline in human plasma. All samples were extracted with ethyl acetate and separated on an Astec Chirobiotic T column under isocratic elution with a mobile phase consisting of methanol and water with the addition of 20mm ammonium acetate and 0.005% (v/v) formic acid at 0.6mL/min. The analytes were detected by a Xevo TQ-S tandem mass spectrometer with positive electrospray ionization in multiple reaction monitoring mode. The established method has high sensitivity with the lower limit of quantifications of 25.00pg/mL for bambuterol enantiomers, and 50.00pg/mL for monocarbamate bambuterol and terbutaline enantiomers, respectively. The calibration curves for bambuterol enantiomers were linear in the range of 25.00-2500pg/mL, and for monocarbamate bambuterol and terbutaline enantiomers were linear in the range of 50.00-5000pg/mL. The intra- and inter-day precisions were <12.4%. All the analytes were separated in 18.0min. For the first time, the validated method was successfully applied to an enantioselective pharmacokinetic study of rac-bambuterol in 8 healthy volunteers. According to the results, this chiral LC-MS/MS assay provides a suitable and robust method for the enantioselectivity and interaction study of the prodrug bambuterol, the key intermediate monocarbamate bambuterol and its active drug terbutaline in human. Copyright © 2015 Elsevier B.V. All rights reserved.

Intermediate treatments

Science.gov (United States)

John R. Jones; Wayne D. Shepperd

1985-01-01

Intermediate treatments are those applied after a new stand is successfully established and before the final harvest. These include not only intermediate cuttings - primarily thinning - but also fertilization, irrigation, and protection of the stand from damaging agents.

Generation, transport and conduct of radioactive wastes of low and intermediate level; Generacion, transporte y gestion de desechos radiactivos de nivel bajo e intermedio

Energy Technology Data Exchange (ETDEWEB)

Lizcano, D.; Jimenez, J. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: dlc@nuclear.inin.mx

2005-07-01

The technological development of the last decades produced an increment in the application of the radiations in different human activities. The effect of it has been it the production of radioactive wastes of all the levels. In Mexico, some of the stages of the administration of the waste of low and intermediate level have not been completely resolved, as the case of the treatment and the final storage. In this work aspects of the generation, the transport and the administration of radioactive waste of low and intermediate level produced in the non energy applications from the radioactive materials to national level, indicating the generated average quantities, transported and tried annually by the National Institute of Nuclear Research (ININ). The main generators of wastes in Mexico, classified according to the activity in which the radioactive materials are used its are listed. Some of the main processes of treatment of radioactive wastes broadly applied in the world and those that are used at the moment in our country are also presented. (Author)

Green and simple analytical method to determine benzimidazoles in milk samples by using salting-out assisted liquid-liquid extraction and capillary liquid chromatography.

Science.gov (United States)

Tejada-Casado, Carmen; Del Olmo-Iruela, Monsalud; García-Campaña, Ana M; Lara, Francisco J

2018-08-01

A green and simple multiresidue method using capillary liquid chromatography (CLC) with UV-diode array detection (DAD) has been developed for the determination of sixteen benzimidazoles (BZs) and its metabolites in milk samples. The separation was achieved in  0.9985 for all BZs) with limits of detection (LOD) between 1.0 and 2.8 μg kg -1 . Relative standard deviations of repeatability and intermediate precision were below 1.6 and 14.2%, respectively. Satisfactory recoveries between 79.1 and 99.6% were also obtained for three types of milk samples (cow, sheep and goat). The advantages of a miniaturized technique such as CLC in terms of better efficiencies and reduced solvent consumption, combined with the simplicity of the SALLE procedure, make this method a useful alternative for the monitoring of these residues at trace level. Copyright © 2018 Elsevier B.V. All rights reserved.

Visual dictionaries as intermediate features in the human brain

Directory of Open Access Journals (Sweden)

Kandan eRamakrishnan

2015-01-01

Full Text Available The human visual system is assumed to transform low level visual features to object and scene representations via features of intermediate complexity. How the brain computationally represents intermediate features is still unclear. To further elucidate this, we compared the biologically plausible HMAX model and Bag of Words (BoW model from computer vision. Both these computational models use visual dictionaries, candidate features of intermediate complexity, to represent visual scenes, and the models have been proven effective in automatic object and scene recognition. These models however differ in the computation of visual dictionaries and pooling techniques. We investigated where in the brain and to what extent human fMRI responses to short video can be accounted for by multiple hierarchical levels of the HMAX and BoW models. Brain activity of 20 subjects obtained while viewing a short video clip was analyzed voxel-wise using a distance-based variation partitioning method. Results revealed that both HMAX and BoW explain a significant amount of brain activity in early visual regions V1, V2 and V3. However BoW exhibits more consistency across subjects in accounting for brain activity compared to HMAX. Furthermore, visual dictionary representations by HMAX and BoW explain significantly some brain activity in higher areas which are believed to process intermediate features. Overall our results indicate that, although both HMAX and BoW account for activity in the human visual system, the BoW seems to more faithfully represent neural responses in low and intermediate level visual areas of the brain.

Asset Opacity and Liquidity

OpenAIRE

Stenzel, A.; Wagner, W.B.

2013-01-01

Abstract: We consider a model of private information acquisition in which the cost of information depends on an asset's opacity. The model generates a hump-shaped relationship between opacity and the equilibrium amount of private information. In particular, the incentives to acquire information are largest for assets of intermediate opacity; such assets hence display low liquidity in the secondary market due to adverse selection. We also show that costly information acquisition generates ince...

Phase behaviour of macromolecular liquid crystalline materials. Computational studies at the molecular level

International Nuclear Information System (INIS)

Stimson, Lorna M.

2003-01-01

Molecular simulations provide an increasingly useful insight into the static and dynamic characteristics of materials. In this thesis molecular simulations of macro-molecular liquid crystalline materials are reported. The first liquid crystalline material that has been investigated is a side chain liquid crystal polymer (SCLCP). In this study semi-atomistic molecular dynamics simulations have been conducted at a range of temperatures and an aligning potential has been applied to mimic the effect of a magnetic field. In cooling the SCLCP from an isotropic melt, microphase separation was observed yielding a domain structure. The application of a magnetic field to this structure aligns the domains producing a stable smectic mesophase. This is the first study in which mesophases have been observed using an off-lattice model of a SCLCP. The second material that has been investigated is a dendrimer with terminal mesogenic functionalization. Here, a multi-scale approach has been taken with Monte Carlo studies of a single dendrimer molecule in the gas phase at the atomistic level, semi-atomistic molecular dynamics of a single molecule in liquid crystalline solvents and a coarse-grained molecular dynamics study of the dendrimer in the bulk. The coarse-grained model has been developed and parameterized using the results of the atomistic and semi-atomistic work. The single molecule studies showed that the liquid crystalline dendrimer was able to change its structure by conformational changes in the flexible chains that link the mesogenic groups to the core. Structural change was seen under the application of a mean field ordering potential in the gas phase, and in the presence of liquid crystalline solvents. No liquid crystalline phases were observed for the bulk phase studies of the coarse-grained model. However, when the length of the mesogenic units was increased there was some evidence for microphase separation in these systems. (author)

Annual report on the effluent control of low level liquid water in Tokai Works. FY2004

International Nuclear Information System (INIS)

Takeishi, Minoru; Miyagawa, Naoto; Watanabe, Hitoshi

2005-08-01

This report was written about the effluent control of low level liquid waste in JNC Tokai Works Fiscal Year 2004, from 1st April 2004 to 31th March 2005. In this period, the quantities and concentrations of radioactivity in liquid waste from Tokai Works were under the discharge limits of 'Safety Regulations for the Tokai Reprocessing Plant' and regulations of government. (author)

Solid Catalyst with Ionic Liquid Layer (SCILL). A concept to improve the selectivity of selective hydrogenations

Energy Technology Data Exchange (ETDEWEB)

Jess, A.; Korth, W. [Bayreuth Univ. (Germany). Chair of Chemical Engineering

2011-07-01

Catalytic hydrogenations are important for refinery processes, petrochemical applications as well as for numerous processes of the fine chemicals industry. In some cases, hydrogenations consist of a sequence of consecutive reactions, and the desired product is the intermediate. An important goal is then a high yield and selectivity to the intermediate, if possible at a high conversion degree. The selectivity to an intermediate primarily depends on the chemical nature of the catalyst, but may also be influenced by diffusion processes. Ionic liquids (ILs) are low melting salts (< 100 C) and represent a promising solvent class. This paper focuses on the concept of a Solid Catalyst with Ionic Liquid Layer (SCILL), where the solid catalyst is coated with a thin IL layer to improve the selectivity. (orig.)

Mono-, bi-, and tri-metallic Ni-based catalysts for the catalytic hydrotreatment of pyrolysis liquids

NARCIS (Netherlands)

Yin, Wang; Venderbosch, Robbie H.; He, Songbo; Bykova, Maria V.; Khromova, Sofia A.; Yakovlev, Vadim A.; Heeres, Hero J.

Catalytic hydrotreatment is a promising technology to convert pyrolysis liquids into intermediates with improved properties. Here, we report a catalyst screening study on the catalytic hydrotreatment of pyrolysis liquids using bi- and tri-metallic nickel-based catalysts in a batch autoclave (initial

Water level response measurement in a steel cylindrical liquid storage tank using image filter processing under seismic excitation

Science.gov (United States)

Kim, Sung-Wan; Choi, Hyoung-Suk; Park, Dong-Uk; Baek, Eun-Rim; Kim, Jae-Min

2018-02-01

Sloshing refers to the movement of fluid that occurs when the kinetic energy of various storage tanks containing fluid (e.g., excitation and vibration) is continuously applied to the fluid inside the tanks. As the movement induced by an external force gets closer to the resonance frequency of the fluid, the effect of sloshing increases, and this can lead to a serious problem with the structural stability of the system. Thus, it is important to accurately understand the physics of sloshing, and to effectively suppress and reduce the sloshing. Also, a method for the economical measurement of the water level response of a liquid storage tank is needed for the exact analysis of sloshing. In this study, a method using images was employed among the methods for measuring the water level response of a liquid storage tank, and the water level response was measured using an image filter processing algorithm for the reduction of the noise of the fluid induced by light, and for the sharpening of the structure installed at the liquid storage tank. A shaking table test was performed to verify the validity of the method of measuring the water level response of a liquid storage tank using images, and the result was analyzed and compared with the response measured using a water level gauge.

Development of Fe-based superconducting wires for liquid-hydrogen level sensors

Science.gov (United States)

Ishida, S.; Tsuchiya, Y.; Mawatari, Y.; Eisaki, H.; Nakano, A.; Yoshida, Y.

2017-07-01

We developed liquid-hydrogen (LH2) level sensors with Ba(Fe1-x Co x )2As2 superconducting wires (Co-Ba122 wires) as their detection elements. We fabricated Co-Ba122 wires with different Co concentrations x by using the powder-in-tube method. The superconducting transition temperatures of the wires were successfully controlled in the range of 20-25 K by changing x from 0.06 to 0.10. The resistance-temperature curves of the wires exhibited sharp superconducting transitions with widths of 0.5-1.0 K. In addition, we performed an operation test of the Co-Ba122 level sensors with LH2. Close correspondence between the output resistance and the actual LH2 level was observed for a sensor equipped with x = 0.09 wire, demonstrating that this sensor can accurately measure LH2 levels.

Vitrification of high-level liquid wastes

International Nuclear Information System (INIS)

Varani, J.L.; Petraitis, E.J.; Vazquez, Antonio.

1987-01-01

High-level radioactive liquid wastes produced in the fuel elements reprocessing require, for their disposal, a preliminary treatment by which, through a series of engineering barriers, the dispersion into the biosphere is delayed by 10 000 years. Four groups of compounds are distinguished among a great variety of final products and methods of elaboration. From these, the borosilicate glasses were chosen. Vitrification experiences were made at a laboratory scale with simulated radioactive wastes, employing different compositions of borosilicate glass. The installations are described. A series of tests were carried out on four basic formulae using always the same methodology, consisting of a dry mixture of the vitreous matrix's products and a dry simulated mixture. Several quality tests of the glasses were made 1: Behaviour in leaching following the DIN 12 111 standard; 2: Mechanical resistance; parameters related with the facility of the different glasses for increasing their surface were studied; 3: Degree of devitrification: it is shown that devitrification turns the glasses containing radioactive wastes easily leachable. From all the glasses tested, the composition SiO 2 , Al 2 O 3 , B 2 O 3 , Na 2 O, CaO shows the best retention characteristics. (M.E.L.) [es

Molecular-level mechanisms of vibrational frequency shifts in a polar liquid.

Science.gov (United States)

Morales, Christine M; Thompson, Ward H

2011-06-16

A molecular-level analysis of the origins of the vibrational frequency shifts of the CN stretching mode in neat liquid acetonitrile is presented. The frequency shifts and infrared spectrum are calculated using a perturbation theory approach within a molecular dynamics simulation and are in good agreement with measured values reported in the literature. The resulting instantaneous frequency of each nitrile group is decomposed into the contributions from each molecule in the liquid and by interaction type. This provides a detailed picture of the mechanisms of frequency shifts, including the number of surrounding molecules that contribute to the shift, the relationship between their position and relative contribution, and the roles of electrostatic and van der Waals interactions. These results provide insight into what information is contained in infrared (IR) and Raman spectra about the environment of the probed vibrational mode. © 2011 American Chemical Society

Liquid chromatography tandem mass spectrometry determination of total budesonide levels in dog plasma after inhalation exposure.

Science.gov (United States)

Berg, Seija; Melamies, Marika; Rajamäki, Minna; Vainio, Outi; Peltonen, Kimmo

2012-01-01

A sensitive and selective method to quantify budesonide in dog plasma samples was developed and fully validated. Liquid-liquid extraction was followed by solid-phase extraction and liquid chromatography-tandem mass spectrometry with electrospray ionization. After reconstitution of the analytes in the mobile phase, samples were analysed by reversed-phase liquid chromatography with isocratic elution. d8-Budesonide was used as an internal standard, and characteristic transitions of d8-budesonide and budesonide were used for quantification. The method was validated with respect to selectivity, specificity, linearity, recovery, repeatability, reproducibility and limits of detection and quantification. The validated method was successfully applied to monitor the plasma levels of budesonide in dogs exposed to clinical doses of inhaled and intravenous drug.

Frequency modulation detection atomic force microscopy in the liquid environment

Science.gov (United States)

Jarvis, S. P.; Ishida, T.; Uchihashi, T.; Nakayama, Y.; Tokumoto, H.

True atomic resolution imaging using frequency modulation detection is already well established in ultra-high vacuum. In this paper we demonstrate that it also has great potential in the liquid environment. Using a combination of magnetic activation and high-aspect-ratio carbon nanotube probes, we show that imaging can be readily combined with point spectroscopy, revealing both the tip-sample interaction and the structure of the intermediate liquid.

Design perspectives for the low and intermediate level radioactive waste repository in Korea

International Nuclear Information System (INIS)

Kim, Young Ki; Koh, Kwang Hoon; Lee, Sang Sun; Lee, Byung Sik; Choi, Gi Won

2007-01-01

The underground waste repository is located at Gyeongju and is designed for the disposal of all the Low- and Intermediate Level Radioactive Waste(LILW). It is scheduled to commence operations in the beginning of 2009. The repository, with a disposal capacity of 800,000 drums, will be constructed in granite rock near the seashore at the Gyeongju site. The repository will be designed to be constructed in phases to reach its final capacity 800,000 drums. In the first phase of construction, the repository will have a capacity to store 100,000 drums. The repository will house all LILW generated in the Republic of Korea. The first phase of the repository design consists of an assess shaft, a construction tunnel, an operating tunnel, an unloading tunnel, and six(6) silos. The silos are located at 80 to 130 meters below Mean Sea level (MSL), in bedrock. Each silo is 24.8m in diameter and 52.4m in height. The silo will be reinforced with concrete lining for rock supports which will also act aas an engineered barrier in limiting radioactive nuclide release aft closure. After serving its intended function the repository will be filled and sealed. The primary objective of filling and sealing is to prevent ground water flow into the silo through the tunnel system and to prevent inadvertent intrusion into the repository after closure

A Novel Acoustic Liquid Level Determination Method for Coal Seam Gas Wells Based on Autocorrelation Analysis

Directory of Open Access Journals (Sweden)

Ximing Zhang

2017-11-01

Full Text Available In coal seam gas (CSG wells, water is periodically removed from the wellbore in order to keep the bottom-hole flowing pressure at low levels, facilitating the desorption of methane gas from the coal bed. In order to calculate gas flow rate and further optimize well performance, it is necessary to accurately monitor the liquid level in real-time. This paper presents a novel method based on autocorrelation function (ACF analysis for determining the liquid level in CSG wells under intense noise conditions. The method involves the calculation of the acoustic travel time in the annulus and processing the autocorrelation signal in order to extract the weak echo under high background noise. In contrast to previous works, the non-linear dependence of the acoustic velocity on temperature and pressure is taken into account. To locate the liquid level of a coal seam gas well the travel time is computed iteratively with the non-linear velocity model. Afterwards, the proposed method is validated using experimental laboratory investigations that have been developed for liquid level detection under two scenarios, representing the combination of low pressure, weak signal, and intense noise generated by gas flowing and leakage. By adopting an evaluation indicator called Crest Factor, the results have shown the superiority of the ACF-based method compared to Fourier filtering (FFT. In the two scenarios, the maximal measurement error from the proposed method was 0.34% and 0.50%, respectively. The latent periodic characteristic of the reflected signal can be extracted by the ACF-based method even when the noise is larger than 1.42 Pa, which is impossible for FFT-based de-noising. A case study focused on a specific CSG well is presented to illustrate the feasibility of the proposed approach, and also to demonstrate that signal processing with autocorrelation analysis can improve the sensitivity of the detection system.

Eco-friendly Energy Storage System: Seawater and Ionic Liquid Electrolyte.

Science.gov (United States)

Kim, Jae-Kwang; Mueller, Franziska; Kim, Hyojin; Jeong, Sangsik; Park, Jeong-Sun; Passerini, Stefano; Kim, Youngsik

2016-01-08

As existing battery technologies struggle to meet the requirements for widespread use in the field of large-scale energy storage, novel concepts are urgently needed concerning batteries that have high energy densities, low costs, and high levels of safety. Here, a novel eco-friendly energy storage system (ESS) using seawater and an ionic liquid is proposed for the first time; this represents an intermediate system between a battery and a fuel cell, and is accordingly referred to as a hybrid rechargeable cell. Compared to conventional organic electrolytes, the ionic liquid electrolyte significantly enhances the cycle performance of the seawater hybrid rechargeable system, acting as a very stable interface layer between the Sn-C (Na storage) anode and the NASICON (Na3 Zr2 Si2 PO12) ceramic solid electrolyte, making this system extremely promising for cost-efficient and environmentally friendly large-scale energy storage. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Low and intermediate radioactive waste management at OPG's western waste management facility

International Nuclear Information System (INIS)

Ellsworth, M.

2006-01-01

'Full text:' This paper will discuss low and intermediate level radioactive waste operations at Ontario Power Generation's Western Waste Management Facility. The facility has been in operation since 1974 and receives about 5000 - 7000 m 3 of low and intermediate level radioactive waste per year from Ontario's nuclear power plants. Low-level radioactive waste is received at the Waste Volume Reduction Building for possible volume reduction before it is placed into storage. Waste may be volume reduced by one of two methods at the WWMF, through either compaction or incineration. The Compactor is capable of reducing the volume of waste by a factor up to 5:1 for most waste. The Radioactive Incinerator is capable of volume reducing incinerable material by a factor up to 70:1. After processing, low-level waste is stored in above ground concrete warehouse-like structures called Low Level Storage Buildings. Low-level waste that cannot be volume reduced is placed into steel containers and stored in the Low Level Storage Buildings. Intermediate level waste is stored mainly in steel lined concrete storage structures. WWMF has both above ground and in-ground storage structures for intermediate level waste. Intermediate level waste consists primarily of resin and filters used to keep reactor water systems clean, and some used reactor core components. All low and intermediate level waste storage at the WWMF is considered interim storage and the material can be retrieved for future disposal or permanent storage. Current improvement initiatives include the installation of a new radioactive incinerator and a shredder/bagger. The new incinerator is a continuous feed system that is expected to achieve volume reduction rates up to 70:1, while incinerating higher volumes of waste than its predecessor. The shredder will break down large/bulky items into a form, which can be processed for further volume reduction. A Refurbishment Waste Storage Project is underway in anticipation of the

A preliminary assessment of polymer-modified cements for use in immobilisation of intermediate level radioactive waste

International Nuclear Information System (INIS)

Burnay, S.G.; Dyson, J.R.

1982-11-01

A range of polymer-modified cements has been examined as candidate materials for the immobilisation of intermediate level radioactive waste. The waste streams studied were inactive simulates of real wastes and included ion-exchange resins, Magnox debris and dilute sludges. Preliminary experiments on the compatibility of the polymer-cement-waste combinations have been carried out and measurements of flexural strength before and after #betta#-irradiation to 10 9 rad and water immersion have been made. Soxhlet leach tests have been used to compare the leach rates of the different materials. From the results of these preliminary experiments, a limited number of polymer-modified cements have been suggested as suitable for more detailed study. (author)

MODELING OF THE HEAT PUMP STATION ADJUSTABLE LOOP OF AN INTERMEDIATE HEAT-TRANSFER AGENT (Part I

Directory of Open Access Journals (Sweden)

Sit B.

2009-08-01

Full Text Available There are examined equations of dynamics and statics of an adjustable intermediate loop of heat pump carbon dioxide station in this paper. Heat pump station is a part of the combined heat supply system. Control of transferred thermal capacity from the source of low potential heat source is realized by means of changing the speed of circulation of a liquid in the loop and changing the area of a heat-transmitting surface, both in the evaporator, and in the intermediate heat exchanger depending on the operating parameter, for example, external air temperature and wind speed.

Heat transfer in intermediate heat exchanger under low flow rate conditions

International Nuclear Information System (INIS)

Mochizuki, H.

2008-01-01

The present paper describes the heat transfer in intermediate heat exchangers (IHXs) of liquid metal cooled fast reactors when flow rate is low such as a natural circulation condition. Although empirical correlations of heat transfer coefficients for IHX were derived using test data at the fast reactor 'Monju' and 'Joyo' and also at the 50 MW steam generator facility, the heat transfer coefficient was very low compared to the well known correlation for liquid metals proposed by Seban-Shimazaki. The heat conduction in IHX was discussed as a possible cause of the low Nusselt number. As a result, the heat conduction is not significant under the natural circulation condition, and the heat conduction term in the energy equation can be neglected in the one-dimensional plant dynamics calculation. (authors)

Seeing is Believing: Simulating Resource-Extraction Problems With Gams Ide and Microsoft Excel in an Intermediate-Level Natural-Resource Economics Course

OpenAIRE

Caplan, Arthur J.

2004-01-01

In this paper we provide several GAMS- and Excel-based resource-extraction models that can be used in an intermediate-level natural-resource economics course to numerically solve a host of exhaustible- and replenishable-resource problems, and thereby help verify the intuition and symbolic solutions provided in the textbook. The specific textbook from which the examples are drawn is Tietenberg (2003).

Reactivity of Criegee Intermediates toward Carbon Dioxide.

Science.gov (United States)

Lin, Yen-Hsiu; Takahashi, Kaito; Lin, Jim Jr-Min

2018-01-04

Recent theoretical work by Kumar and Francisco suggested that the high reactivity of Criegee intermediates (CIs) could be utilized for designing efficient carbon capture technologies. Because the anti-CH 3 CHOO + CO 2 reaction has the lowest barrier in their study, we chose to investigate it experimentally. We probed anti-CH 3 CHOO with its strong UV absorption at 365 nm and measured the rate coefficient to be ≤2 × 10 -17 cm 3 molecule -1 s -1 at 298 K, which is consistent with our theoretical value of 2.1 × 10 -17 cm 3  molecule -1 s -1 at the QCISD(T)/CBS//B3LYP/6-311+G(2d,2p) level but inconsistent with their results obtained at the M06-2X/aug-cc-pVTZ level, which tends to underestimate the barrier heights. The experimental result indicates that the reaction of a Criegee intermediate with atmospheric CO 2 (400 ppmv) would be inefficient (k eff < 0.2 s -1 ) and cannot compete with other decay processes of Criegee intermediates like reactions with water vapor (∼10 3 s -1 ) or thermal decomposition (∼10 2 s -1 ).

The incorporation of low and medium level radioactive wastes (solids and liquids) in cement

International Nuclear Information System (INIS)

Palmer, J.D.; Smith, D.L.G.

1986-01-01

The use of cement has been investigated for the immobilization of liquid and solid low and medium level radioactive waste. 220 litre mixing trials have demonstrated that the high temperatures generated during the setting of ordinary Portland cement/simulant waste mixes can be significantly reduced by the use of a blend of ground granulated blast furnace slag and ordinary Portland cement. Laboratory and 220 litre trials using simulant wastes showed that the blended cement gave an improvement in properties of the cemented waste product, e.g. stability and reduction in leach rates compared with ordinary Portland cement formulations. A range of 220 litre scale mixing systems for the incorporation of liquid and solid wastes in cement was investigated. The work has confirmed that cement-based processes can be used for the immobilization of most types of low and medium level waste

Experimental study on the performance of the vapor injection refrigeration system with an economizer for intermediate pressures

Science.gov (United States)

Moon, Chang-Uk; Choi, Kwang-Hwan; Yoon, Jung-In; Kim, Young-Bok; Son, Chang-Hyo; Ha, Soo-Jung; Jeon, Min-Ju; An, Sang-Young; Lee, Joon-Hyuk

2018-04-01

In this study, to investigate the performance characteristics of vapor injection refrigeration system with an economizer at an intermediate pressure, the vapor injection refrigeration system was analyzed under various experiment conditions. As a result, the optimum design data of the vapor injection refrigeration system with an economizer were obtained. The findings from this study can be summarized as follows. The mass flow rate through the compressor increases with intermediate pressure. The compression power input showed an increasing trend under all the test conditions. The evaporation capacity increased and then decreased at the intermediate pressure, and as such, it became maximum at the given intermediate pressure. The increased mass flow rate of the by-passed refrigerant enhanced the evaporation capacity at the low medium pressure range, but the increased saturation temperature limited the subcooling degree of the liquid refrigerant after the application of the economizer when the intermediate pressure kept rising, and degenerated the evaporation capacity. The coefficient of performance (COP) increased and then decreased with respect to the intermediate pressures under all the experiment conditions. Nevertheless, there was an optimum intermediate pressure for the maximum COP under each experiment condition. Therefore, the optimum intermediate pressure in this study was found at -99.08 kPa, which is the theoretical standard medium pressure under all the test conditions.

Liquid dynamics and inelastic scattering of neutrons

Energy Technology Data Exchange (ETDEWEB)

De Gennes, P. G. [Commissariat a l' energie atomique et aux energies alternatives - CEA, CEN de Saclay, Gif sur Yvette (France)

1960-07-01

The energy transfers in one collision between a neutron and a liquid are computed by a method of moments. It is shown that for large momentum transfers a perfect gas model is correct. For small momentum transfers a macroscopic description of the density fluctuations in the liquid is applicable. It is in the intermediate region (where diffraction peaks are observed) that the method of moments is most useful. These different experimental situations are discussed for liquids where recoil and quantum effects are negligible, and numerical results are given for argon. An approximation for the so called autocorrelation function, valid for both long and short time scales and all distances, is also presented. Reprint of a paper published in Physica 25, 1959, p. 825-839.

Intermediate statistics in quantum maps

Energy Technology Data Exchange (ETDEWEB)

Giraud, Olivier [H H Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Marklof, Jens [School of Mathematics, University of Bristol, University Walk, Bristol BS8 1TW (United Kingdom); O' Keefe, Stephen [School of Mathematics, University of Bristol, University Walk, Bristol BS8 1TW (United Kingdom)

2004-07-16

We present a one-parameter family of quantum maps whose spectral statistics are of the same intermediate type as observed in polygonal quantum billiards. Our central result is the evaluation of the spectral two-point correlation form factor at small argument, which in turn yields the asymptotic level compressibility for macroscopic correlation lengths. (letter to the editor)

The use of ultrasonic instrumentation in liquid/liquid extraction plant

International Nuclear Information System (INIS)

Asher, R.C.; Bradshaw, L.; Tolchard, A.C.

1984-01-01

Ultrasonic instruments can be used to determine many of the parameters of interest in a liquid/liquid extraction plant, eg liquid levels, the position of interfaces between immiscible liquids and the concentration of solutions. The determinations can often be made non-invasively. A number of instruments developed for a liquid/liquid extraction plant used for nuclear fuel reprocessing is described. These instruments have a wider application in liquid/liquid extraction plant in general. (author)

Bank regulatory Capital Buffer and Liquidity: Evidence from US and European Publicly Traded Banks

OpenAIRE

Distinguin , Isabelle; Roulet , Caroline; Tarazi , Amine

2012-01-01

The theory of financial intermediation highlights various channels through which capital and liquidity are interrelated. Using a simultaneous equations framework, we investigate the relationship between bank regulatory capital buffer and liquidity for European and U.S. publicly traded commercial banks. Previous research studying the determinants of bank capital buffer has neglected the role of liquidity. On the whole, we find that banks do not strengthen their regulatory capital buffer when t...

Review of environmental surveillance data around low-level waste disposal areas at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Oakes, T.W.; Shank, K.E.

1979-01-01

White Oak Creek and Melton Branch tributary surface streams flow through the Oak Ridge National Laboratory (ORNL) reservation and receive treated low-level radioactive liquid waste which originates from various Laboratory operations. The streams receive additional low-level liquid waste generated by seepage of radioactive materials from solid-waste burial grounds, hydrofracture sites, and intermediate-level liquid-waste sites. Over the years, various liquid-waste treatment and disposal processes have been employed at ORNL; some of these processes have included: settling basins, impoundment, storage tanks, evaporation, ground disposal in trenches and pits, and hydrofracture. Burial of solid radioactive waste was initiated in the early 1940's, and there are six burial grounds at ORNL with two currently in use. Monitoring at White Oak Dam, the last liquid control point for the Laboratory, was started in the late 1940's and is continuing. Presently, a network of five environmental monitoring stations is in operation to monitor the radionuclide content of surface waters in the White Oak watershed. In this paper, the solid waste burial grounds will be described in detail, and the environmental data tabulated over the past 29 years will be presented. The various monitoring systems used during the years will also be reviewed. The liquid effluent discharge trends at ORNL from the radioactive waste operations will be discussed

Low- and Intermediate Level Radioactive Waste Disposal Environmental and Safety Assessment Activities in Slovenia

International Nuclear Information System (INIS)

Marc, D.; Loose, A.; Urbanc, J.

1998-01-01

The protection of the environment is one of the main concerns in the management of radioactive waste, especially in repository planning. In different stages of repository lifetime the environmental assessment has different functions: it can be used as a decision making process and as a planning, communication and management tool. Safety assessment as a procedure for evaluating the performance of a disposal system, and its potential radiological impact on human health and environment, is also required. Following the international recommendations and Slovene legislation, a presentation is given of the role and importance of the environmental and safety assessment activities in the early stages following concept development and site selection for a low- and intermediate level radioactive waste (LILW) repository in Slovenia. As a case study, a short overview is also given of the preliminary safety assessment that has been carried out in the analysis of possibilities for long-lived LILW disposal in Slovenia. (author)

The Effect of Pulsed Streamer-like Discharge in Liquid on Transcriptional Activation of Retrotransposon Genes of a Red Alga, Porphyra Yezoensis

OpenAIRE

Ohno, T.; Li, Z.; Lin, X.F.; Zhang, W.B.; Takano, H.; Takio, S.; Namihira, T.; Akiyama, H.; オオノ, ツヨシ; ナミヒラ, タカオ; アキヤマ, ヒデノリ; 大野, 剛史; 浪平, 隆男; 秋山, 秀典

2007-01-01

Retrotransposons are mobile genetic elements thataccomplished transposition via an RNA intermediate.These elements can be transcriptionally activated by stressfactors, such as UV light, ozone, pathogens, woundingand drought. A red alga, porphyra yezoensis has recentlybeen recognized as a model plant for fundamental andapplied study in marine biological science. In this paper,pulsed streamer-like discharge in liquid was used as a newstress condition, and the transcription level of a copia-like...

Experimental Investigation of Liquid-Level Measuring Accuracy in a Low Pressure Environment

International Nuclear Information System (INIS)

Adamson, D.J.

1996-10-01

Dip Tubes which are used for determining liquid level in many processes at SRS will be used to measure the liquid level of the Am/Cm solution in the Feed Tank at the MPPF. The Feed Tank operates under a vacuum, therefore the Dip Tubes will operate under a vacuum. Uncertainty in how accurate the Dip Tubes would perform in a vacuum environment led to testing. The Am/Cm Melter Liquid-Feed Tank measurement test was mocked-up per Figure 1. The Feed Tank was designed to simulate actual conditions in which the Dip Tubes would measure the differential pressure. The Feed Tank was made of Stainless Steel with a Lexan window to view inside the tank during testing. The Feed Tank was built per Drawing SRT-ETF-DD-96008, Revision A. The accuracy of the Dip Tubes was checked first by filling the Feed Tank at a flow rate of 3.5 L/min and venting it to the atmosphere. Figure 2 shows that the Dip Tubes were responsive and accurate when compared to the data from the measuring scale on the view window. Then tests were conducted with 23y Hg vacuum inside the tank and water flow rates of 3.9 L/min, 1.8 L/min, and 0.7 L/min being fed to the tank. The data from each test are depicted in Figure 3, Figure 4, and Figure 5, respectively. The Dip Tubes responded accurately for the three test with a maximum error range of +0.31y to -0.19y when compared to the measuring scale located next to the view window on the Feed Tank

Evaluation of low and intermediate level radioactive solidified waste forms and packages

International Nuclear Information System (INIS)

1990-10-01

Evaluation of low and intermediate level radioactive waste forms and packages with respect to compliance with quality and safety requirements for transport, interim storage and disposal has become a very important part of the radioactive waste management strategy in many countries. The evaluation of waste forms and packages provides precise basic data for regulatory bodies to establish safety requirements, and implement quality control and quality assurance procedures for radioactive waste management programmes. The requirements depend very much upon the disposal option selected, treatment technology used, waste form characteristics, package quality and other factors. The regulatory requirements can also influence the methodology of waste form/package evaluation together with selection and analysis of data for quality control and safety assurance. A coordinated research programme started at the end of 1985 and brought together 12 participants from 11 countries. The results of the programme and each particular project were discussed at three Research Coordination Meetings held in Cairo, Egypt, in May, 1986; in Beijing, China, in April, 1998; and at Harwell Laboratory, United Kingdom, in November, 1989. This document summarises the salient features and results achieved during the four year investigation and a recommendation for future work in this area. Refs, figs and tabs

Cryogenic Liquid Sample Acquisition System for Remote Space Applications

Science.gov (United States)

Mahaffy, Paul; Trainer, Melissa; Wegel, Don; Hawk, Douglas; Melek, Tony; Johnson, Christopher; Amato, Michael; Galloway, John

2013-01-01

There is a need to acquire autonomously cryogenic hydrocarbon liquid sample from remote planetary locations such as the lakes of Titan for instruments such as mass spectrometers. There are several problems that had to be solved relative to collecting the right amount of cryogenic liquid sample into a warmer spacecraft, such as not allowing the sample to boil off or fractionate too early; controlling the intermediate and final pressures within carefully designed volumes; designing for various particulates and viscosities; designing to thermal, mass, and power-limited spacecraft interfaces; and reducing risk. Prior art inlets for similar instruments in spaceflight were designed primarily for atmospheric gas sampling and are not useful for this front-end application. These cryogenic liquid sample acquisition system designs for remote space applications allow for remote, autonomous, controlled sample collections of a range of challenging cryogenic sample types. The design can control the size of the sample, prevent fractionation, control pressures at various stages, and allow for various liquid sample levels. It is capable of collecting repeated samples autonomously in difficult lowtemperature conditions often found in planetary missions. It is capable of collecting samples for use by instruments from difficult sample types such as cryogenic hydrocarbon (methane, ethane, and propane) mixtures with solid particulates such as found on Titan. The design with a warm actuated valve is compatible with various spacecraft thermal and structural interfaces. The design uses controlled volumes, heaters, inlet and vent tubes, a cryogenic valve seat, inlet screens, temperature and cryogenic liquid sensors, seals, and vents to accomplish its task.

Experience from developed and licensing an underground repository for low and intermediate level radioactive wastes

International Nuclear Information System (INIS)

Ebel, K.; Richter, D.

1988-01-01

In the German Democratic Republic an abandoned salt mine was selected and reconstructed to serve as a central repository for low and intermediate level wastes from nuclear power plants and radioisotope production and application from all over the country. The decision to establish such a repository was based on safety and technical-economic studies performed in the 1960s. The repository is owned by the main waste producer, the nuclear plant utility. It was designed, constructed and commissioned during 1972-1978. The licensing steps included a site licence (1972), a construction licence (1974), a comissioning licence and a continuous operation licence (1979). The paper reviews the overall choice of the disposal option, the responsibilities in radioactive waste management, the licensing and surveillance activities, the methods for transport and disposal, and the waste acceptance criteria established for the repository. (author)

Scientific and technical basis for the near surface disposal of low and intermediate level waste

International Nuclear Information System (INIS)

2002-01-01

This report presents an overview of the scientific and technical basis for the disposal of low- and intermediate-level radioactive waste in near surface repositories. The focus is on basic principles, approaches, methodologies and technical criteria that can be used to develop and assess the performance of a disposal facility, and for building confidence in repository safety. This includes consideration of the multiple barrier concept, the performance of engineered barriers, the role of natural barriers and the development of a safety case. The emphasis is on defining the conditions relevant to the containment of the radionuclides in the repository and the processes that may affect the integrity of the engineered barriers. Both generic and specific data requirements for repository development and the assurance of safety are addressed. A large number of bibliographical references are given to support the information provided in this report

Cost Considerations and Financing Mechanisms for the Disposal of Low and Intermediate Level Radioactive Waste

International Nuclear Information System (INIS)

2007-06-01

The overall objective of this publication is to provide Member States who are currently planning or preparing new near surface repositories for low and intermediate level radioactive waste (LILW), guidance on cost considerations and funding mechanisms for the repositories' entire life cycle. The report focuses on both technical and non-technical factors affecting repository costs. It considers the major cost elements that comprise a cost evaluation for a disposal facility for LILW and identifies those factors which may result in major uncertainties in an overall cost estimate. In particular, the report lists the basic disposal options and summarizes the legal basis and infrastructure requirements for establishing an effective financing system. It further includes the cost estimation methodology, considers the major cost categories and discusses factors to be considered when planning the financing mechanism, and describes relevant financing schemes

Formation and filtration characteristics of solids generated in a high level liquid waste treatment process. Filtration characteristics of solids formed in simulated high level liquid waste

International Nuclear Information System (INIS)

Kondo, Y.; Kubota, M.

1997-01-01

The filtration characteristics of solids generated in a simulated high level liquid waste (HLLW) were experimentally examined, when the simulated HLLW was processed according to the ordinary way of actual HLLW treatment process. The filtration characteristics of solids depended on the particle size. The phosphomolybdic acid, which was very fine particle with about 0.1 μm diameter, made slurry a 'difficult-to-filter' slurry, if the phosphomolybdic acid content (wt%) to the whole solids in a slurry exceeded 50wt%. On the contrary, the zirconium compounds (zirconium molybdate and zirconium telluride) had positive effect on filtration characteristics because of their relatively large particle size of about 3 to 5 μm. When the zirconium compounds content was above 50 wt%, slurry became a 'easy-to-filter' slurry. A centrifugal sedimentation was discussed as a solid/liquid separation technique for very fine particles such as phosphomolybdic acid. The theoretical feed flow rate corresponded to 0.1 μm diameter particles was about 20 1/h at the centrifugal acceleration of about 8000 G. (author)

Measurement of gross beta radioactivity in high-level liquid waste

International Nuclear Information System (INIS)

Lu Feng; Lin Cansheng; Zhang Xianzi; Chen Guoan; Zhang Chonghai

1992-01-01

Using beta plastic scintillation counter of low level background, gross beta radioactivity of twelve samples for high-level liquid waste is determined directly. Beta efficiency curves of plastic scintillation counter for four mass thickness are calibrated in advance. Determining gross beta radioactivity, gross efficiency of the scintillation counter for various energy beta ray is calculated via weighted mean method with the ratio of radioactivity for each nuclide. The ratio of radioactivity for nuclides which have gamma disintegration is determined in terms of the radioactivity measured by gamma spectrometer. The ratio of the radioactivity for 90 Sr which has purity beta disintegration is calculated in terms of half life time approximation. The ratio of the radioactivity for 147 Pm which also has purity disintegration is calculated by means of apparent cooling-time approximation. The uncertainty of results for the present work is about +-15%

Analytical method used for intermediate products in continuous distillation of furfural

Energy Technology Data Exchange (ETDEWEB)

Wang, Z.L.; Jia, M.; Wang, L.J.; Deng, Y.X.

1981-01-01

During distillation of furfural, analysis of main components in the crude furfural condensate and intermediate products is very important. Since furfural and methylfurfural are homologous and both furfural and acetone contain a carbonyl group, components in the sample must be separated before analysis. An improved analytical method has been studied, the accuracy and precision of which would meet the requirement of industrial standards. The analytical procedure was provided as follows: to determine the furfural content with gravimetric method of barbituric acid; to determine the methanol content with dichromate method after precipitating furfural and acetone, and distilling the liquid for analysis; and to determine the methylfurfural content with bromide-bromate method, which can be used only in the sample containing higher content of methylfurfural. For the sample in low content, the gas-liquid chromatographic method can be used. 7 references.

Thin-film intermediate band chalcopyrite solar cells

International Nuclear Information System (INIS)

Fuertes Marron, D.; Marti, A.; Luque, A.

2009-01-01

Chalcopyrite-based solar cells currently lead the efficiency tables of thin-film photovoltaic technologies. Further improvements are foreseen upon implementation of an intermediate band in the absorber layers. We present a theoretical analysis of the efficiency limit for this type of device as a function of factors such as the gap of the host, the relative position of the intermediate band with respect to the band edge and the level of light concentration used as illumination. We have also considered the impact of non-idealities on the performance of the device, particularly the effect of electronic losses related to non-radiative recombination